Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / tty / synclinkmp.c
diff --git a/kernel/drivers/tty/synclinkmp.c b/kernel/drivers/tty/synclinkmp.c
new file mode 100644 (file)
index 0000000..c3f9091
--- /dev/null
@@ -0,0 +1,5604 @@
+/*
+ * $Id: synclinkmp.c,v 4.38 2005/07/15 13:29:44 paulkf Exp $
+ *
+ * Device driver for Microgate SyncLink Multiport
+ * high speed multiprotocol serial adapter.
+ *
+ * written by Paul Fulghum for Microgate Corporation
+ * paulkf@microgate.com
+ *
+ * Microgate and SyncLink are trademarks of Microgate Corporation
+ *
+ * Derived from serial.c written by Theodore Ts'o and Linus Torvalds
+ * This code is released under the GNU General Public License (GPL)
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#define VERSION(ver,rel,seq) (((ver)<<16) | ((rel)<<8) | (seq))
+#if defined(__i386__)
+#  define BREAKPOINT() asm("   int $3");
+#else
+#  define BREAKPOINT() { }
+#endif
+
+#define MAX_DEVICES 12
+
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/major.h>
+#include <linux/string.h>
+#include <linux/fcntl.h>
+#include <linux/ptrace.h>
+#include <linux/ioport.h>
+#include <linux/mm.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/netdevice.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/ioctl.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/dma.h>
+#include <linux/bitops.h>
+#include <asm/types.h>
+#include <linux/termios.h>
+#include <linux/workqueue.h>
+#include <linux/hdlc.h>
+#include <linux/synclink.h>
+
+#if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINKMP_MODULE))
+#define SYNCLINK_GENERIC_HDLC 1
+#else
+#define SYNCLINK_GENERIC_HDLC 0
+#endif
+
+#define GET_USER(error,value,addr) error = get_user(value,addr)
+#define COPY_FROM_USER(error,dest,src,size) error = copy_from_user(dest,src,size) ? -EFAULT : 0
+#define PUT_USER(error,value,addr) error = put_user(value,addr)
+#define COPY_TO_USER(error,dest,src,size) error = copy_to_user(dest,src,size) ? -EFAULT : 0
+
+#include <asm/uaccess.h>
+
+static MGSL_PARAMS default_params = {
+       MGSL_MODE_HDLC,                 /* unsigned long mode */
+       0,                              /* unsigned char loopback; */
+       HDLC_FLAG_UNDERRUN_ABORT15,     /* unsigned short flags; */
+       HDLC_ENCODING_NRZI_SPACE,       /* unsigned char encoding; */
+       0,                              /* unsigned long clock_speed; */
+       0xff,                           /* unsigned char addr_filter; */
+       HDLC_CRC_16_CCITT,              /* unsigned short crc_type; */
+       HDLC_PREAMBLE_LENGTH_8BITS,     /* unsigned char preamble_length; */
+       HDLC_PREAMBLE_PATTERN_NONE,     /* unsigned char preamble; */
+       9600,                           /* unsigned long data_rate; */
+       8,                              /* unsigned char data_bits; */
+       1,                              /* unsigned char stop_bits; */
+       ASYNC_PARITY_NONE               /* unsigned char parity; */
+};
+
+/* size in bytes of DMA data buffers */
+#define SCABUFSIZE     1024
+#define SCA_MEM_SIZE   0x40000
+#define SCA_BASE_SIZE   512
+#define SCA_REG_SIZE    16
+#define SCA_MAX_PORTS   4
+#define SCAMAXDESC     128
+
+#define        BUFFERLISTSIZE  4096
+
+/* SCA-I style DMA buffer descriptor */
+typedef struct _SCADESC
+{
+       u16     next;           /* lower l6 bits of next descriptor addr */
+       u16     buf_ptr;        /* lower 16 bits of buffer addr */
+       u8      buf_base;       /* upper 8 bits of buffer addr */
+       u8      pad1;
+       u16     length;         /* length of buffer */
+       u8      status;         /* status of buffer */
+       u8      pad2;
+} SCADESC, *PSCADESC;
+
+typedef struct _SCADESC_EX
+{
+       /* device driver bookkeeping section */
+       char    *virt_addr;     /* virtual address of data buffer */
+       u16     phys_entry;     /* lower 16-bits of physical address of this descriptor */
+} SCADESC_EX, *PSCADESC_EX;
+
+/* The queue of BH actions to be performed */
+
+#define BH_RECEIVE  1
+#define BH_TRANSMIT 2
+#define BH_STATUS   4
+
+#define IO_PIN_SHUTDOWN_LIMIT 100
+
+struct _input_signal_events {
+       int     ri_up;
+       int     ri_down;
+       int     dsr_up;
+       int     dsr_down;
+       int     dcd_up;
+       int     dcd_down;
+       int     cts_up;
+       int     cts_down;
+};
+
+/*
+ * Device instance data structure
+ */
+typedef struct _synclinkmp_info {
+       void *if_ptr;                           /* General purpose pointer (used by SPPP) */
+       int                     magic;
+       struct tty_port         port;
+       int                     line;
+       unsigned short          close_delay;
+       unsigned short          closing_wait;   /* time to wait before closing */
+
+       struct mgsl_icount      icount;
+
+       int                     timeout;
+       int                     x_char;         /* xon/xoff character */
+       u16                     read_status_mask1;  /* break detection (SR1 indications) */
+       u16                     read_status_mask2;  /* parity/framing/overun (SR2 indications) */
+       unsigned char           ignore_status_mask1;  /* break detection (SR1 indications) */
+       unsigned char           ignore_status_mask2;  /* parity/framing/overun (SR2 indications) */
+       unsigned char           *tx_buf;
+       int                     tx_put;
+       int                     tx_get;
+       int                     tx_count;
+
+       wait_queue_head_t       status_event_wait_q;
+       wait_queue_head_t       event_wait_q;
+       struct timer_list       tx_timer;       /* HDLC transmit timeout timer */
+       struct _synclinkmp_info *next_device;   /* device list link */
+       struct timer_list       status_timer;   /* input signal status check timer */
+
+       spinlock_t lock;                /* spinlock for synchronizing with ISR */
+       struct work_struct task;                        /* task structure for scheduling bh */
+
+       u32 max_frame_size;                     /* as set by device config */
+
+       u32 pending_bh;
+
+       bool bh_running;                                /* Protection from multiple */
+       int isr_overflow;
+       bool bh_requested;
+
+       int dcd_chkcount;                       /* check counts to prevent */
+       int cts_chkcount;                       /* too many IRQs if a signal */
+       int dsr_chkcount;                       /* is floating */
+       int ri_chkcount;
+
+       char *buffer_list;                      /* virtual address of Rx & Tx buffer lists */
+       unsigned long buffer_list_phys;
+
+       unsigned int rx_buf_count;              /* count of total allocated Rx buffers */
+       SCADESC *rx_buf_list;                   /* list of receive buffer entries */
+       SCADESC_EX rx_buf_list_ex[SCAMAXDESC]; /* list of receive buffer entries */
+       unsigned int current_rx_buf;
+
+       unsigned int tx_buf_count;              /* count of total allocated Tx buffers */
+       SCADESC *tx_buf_list;           /* list of transmit buffer entries */
+       SCADESC_EX tx_buf_list_ex[SCAMAXDESC]; /* list of transmit buffer entries */
+       unsigned int last_tx_buf;
+
+       unsigned char *tmp_rx_buf;
+       unsigned int tmp_rx_buf_count;
+
+       bool rx_enabled;
+       bool rx_overflow;
+
+       bool tx_enabled;
+       bool tx_active;
+       u32 idle_mode;
+
+       unsigned char ie0_value;
+       unsigned char ie1_value;
+       unsigned char ie2_value;
+       unsigned char ctrlreg_value;
+       unsigned char old_signals;
+
+       char device_name[25];                   /* device instance name */
+
+       int port_count;
+       int adapter_num;
+       int port_num;
+
+       struct _synclinkmp_info *port_array[SCA_MAX_PORTS];
+
+       unsigned int bus_type;                  /* expansion bus type (ISA,EISA,PCI) */
+
+       unsigned int irq_level;                 /* interrupt level */
+       unsigned long irq_flags;
+       bool irq_requested;                     /* true if IRQ requested */
+
+       MGSL_PARAMS params;                     /* communications parameters */
+
+       unsigned char serial_signals;           /* current serial signal states */
+
+       bool irq_occurred;                      /* for diagnostics use */
+       unsigned int init_error;                /* Initialization startup error */
+
+       u32 last_mem_alloc;
+       unsigned char* memory_base;             /* shared memory address (PCI only) */
+       u32 phys_memory_base;
+       int shared_mem_requested;
+
+       unsigned char* sca_base;                /* HD64570 SCA Memory address */
+       u32 phys_sca_base;
+       u32 sca_offset;
+       bool sca_base_requested;
+
+       unsigned char* lcr_base;                /* local config registers (PCI only) */
+       u32 phys_lcr_base;
+       u32 lcr_offset;
+       int lcr_mem_requested;
+
+       unsigned char* statctrl_base;           /* status/control register memory */
+       u32 phys_statctrl_base;
+       u32 statctrl_offset;
+       bool sca_statctrl_requested;
+
+       u32 misc_ctrl_value;
+       char *flag_buf;
+       bool drop_rts_on_tx_done;
+
+       struct  _input_signal_events    input_signal_events;
+
+       /* SPPP/Cisco HDLC device parts */
+       int netcount;
+       spinlock_t netlock;
+
+#if SYNCLINK_GENERIC_HDLC
+       struct net_device *netdev;
+#endif
+
+} SLMP_INFO;
+
+#define MGSL_MAGIC 0x5401
+
+/*
+ * define serial signal status change macros
+ */
+#define        MISCSTATUS_DCD_LATCHED  (SerialSignal_DCD<<8)   /* indicates change in DCD */
+#define MISCSTATUS_RI_LATCHED  (SerialSignal_RI<<8)    /* indicates change in RI */
+#define MISCSTATUS_CTS_LATCHED (SerialSignal_CTS<<8)   /* indicates change in CTS */
+#define MISCSTATUS_DSR_LATCHED (SerialSignal_DSR<<8)   /* change in DSR */
+
+/* Common Register macros */
+#define LPR    0x00
+#define PABR0  0x02
+#define PABR1  0x03
+#define WCRL   0x04
+#define WCRM   0x05
+#define WCRH   0x06
+#define DPCR   0x08
+#define DMER   0x09
+#define ISR0   0x10
+#define ISR1   0x11
+#define ISR2   0x12
+#define IER0   0x14
+#define IER1   0x15
+#define IER2   0x16
+#define ITCR   0x18
+#define INTVR  0x1a
+#define IMVR   0x1c
+
+/* MSCI Register macros */
+#define TRB    0x20
+#define TRBL   0x20
+#define TRBH   0x21
+#define SR0    0x22
+#define SR1    0x23
+#define SR2    0x24
+#define SR3    0x25
+#define FST    0x26
+#define IE0    0x28
+#define IE1    0x29
+#define IE2    0x2a
+#define FIE    0x2b
+#define CMD    0x2c
+#define MD0    0x2e
+#define MD1    0x2f
+#define MD2    0x30
+#define CTL    0x31
+#define SA0    0x32
+#define SA1    0x33
+#define IDL    0x34
+#define TMC    0x35
+#define RXS    0x36
+#define TXS    0x37
+#define TRC0   0x38
+#define TRC1   0x39
+#define RRC    0x3a
+#define CST0   0x3c
+#define CST1   0x3d
+
+/* Timer Register Macros */
+#define TCNT   0x60
+#define TCNTL  0x60
+#define TCNTH  0x61
+#define TCONR  0x62
+#define TCONRL 0x62
+#define TCONRH 0x63
+#define TMCS   0x64
+#define TEPR   0x65
+
+/* DMA Controller Register macros */
+#define DARL   0x80
+#define DARH   0x81
+#define DARB   0x82
+#define BAR    0x80
+#define BARL   0x80
+#define BARH   0x81
+#define BARB   0x82
+#define SAR    0x84
+#define SARL   0x84
+#define SARH   0x85
+#define SARB   0x86
+#define CPB    0x86
+#define CDA    0x88
+#define CDAL   0x88
+#define CDAH   0x89
+#define EDA    0x8a
+#define EDAL   0x8a
+#define EDAH   0x8b
+#define BFL    0x8c
+#define BFLL   0x8c
+#define BFLH   0x8d
+#define BCR    0x8e
+#define BCRL   0x8e
+#define BCRH   0x8f
+#define DSR    0x90
+#define DMR    0x91
+#define FCT    0x93
+#define DIR    0x94
+#define DCMD   0x95
+
+/* combine with timer or DMA register address */
+#define TIMER0 0x00
+#define TIMER1 0x08
+#define TIMER2 0x10
+#define TIMER3 0x18
+#define RXDMA  0x00
+#define TXDMA  0x20
+
+/* SCA Command Codes */
+#define NOOP           0x00
+#define TXRESET                0x01
+#define TXENABLE       0x02
+#define TXDISABLE      0x03
+#define TXCRCINIT      0x04
+#define TXCRCEXCL      0x05
+#define TXEOM          0x06
+#define TXABORT                0x07
+#define MPON           0x08
+#define TXBUFCLR       0x09
+#define RXRESET                0x11
+#define RXENABLE       0x12
+#define RXDISABLE      0x13
+#define RXCRCINIT      0x14
+#define RXREJECT       0x15
+#define SEARCHMP       0x16
+#define RXCRCEXCL      0x17
+#define RXCRCCALC      0x18
+#define CHRESET                0x21
+#define HUNT           0x31
+
+/* DMA command codes */
+#define SWABORT                0x01
+#define FEICLEAR       0x02
+
+/* IE0 */
+#define TXINTE                 BIT7
+#define RXINTE                 BIT6
+#define TXRDYE                 BIT1
+#define RXRDYE                 BIT0
+
+/* IE1 & SR1 */
+#define UDRN           BIT7
+#define IDLE           BIT6
+#define SYNCD          BIT4
+#define FLGD           BIT4
+#define CCTS           BIT3
+#define CDCD           BIT2
+#define BRKD           BIT1
+#define ABTD           BIT1
+#define GAPD           BIT1
+#define BRKE           BIT0
+#define IDLD   BIT0
+
+/* IE2 & SR2 */
+#define EOM    BIT7
+#define PMP    BIT6
+#define SHRT   BIT6
+#define PE     BIT5
+#define ABT    BIT5
+#define FRME   BIT4
+#define RBIT   BIT4
+#define OVRN   BIT3
+#define CRCE   BIT2
+
+
+/*
+ * Global linked list of SyncLink devices
+ */
+static SLMP_INFO *synclinkmp_device_list = NULL;
+static int synclinkmp_adapter_count = -1;
+static int synclinkmp_device_count = 0;
+
+/*
+ * Set this param to non-zero to load eax with the
+ * .text section address and breakpoint on module load.
+ * This is useful for use with gdb and add-symbol-file command.
+ */
+static bool break_on_load = 0;
+
+/*
+ * Driver major number, defaults to zero to get auto
+ * assigned major number. May be forced as module parameter.
+ */
+static int ttymajor = 0;
+
+/*
+ * Array of user specified options for ISA adapters.
+ */
+static int debug_level = 0;
+static int maxframe[MAX_DEVICES] = {0,};
+
+module_param(break_on_load, bool, 0);
+module_param(ttymajor, int, 0);
+module_param(debug_level, int, 0);
+module_param_array(maxframe, int, NULL, 0);
+
+static char *driver_name = "SyncLink MultiPort driver";
+static char *driver_version = "$Revision: 4.38 $";
+
+static int synclinkmp_init_one(struct pci_dev *dev,const struct pci_device_id *ent);
+static void synclinkmp_remove_one(struct pci_dev *dev);
+
+static struct pci_device_id synclinkmp_pci_tbl[] = {
+       { PCI_VENDOR_ID_MICROGATE, PCI_DEVICE_ID_MICROGATE_SCA, PCI_ANY_ID, PCI_ANY_ID, },
+       { 0, }, /* terminate list */
+};
+MODULE_DEVICE_TABLE(pci, synclinkmp_pci_tbl);
+
+MODULE_LICENSE("GPL");
+
+static struct pci_driver synclinkmp_pci_driver = {
+       .name           = "synclinkmp",
+       .id_table       = synclinkmp_pci_tbl,
+       .probe          = synclinkmp_init_one,
+       .remove         = synclinkmp_remove_one,
+};
+
+
+static struct tty_driver *serial_driver;
+
+/* number of characters left in xmit buffer before we ask for more */
+#define WAKEUP_CHARS 256
+
+
+/* tty callbacks */
+
+static int  open(struct tty_struct *tty, struct file * filp);
+static void close(struct tty_struct *tty, struct file * filp);
+static void hangup(struct tty_struct *tty);
+static void set_termios(struct tty_struct *tty, struct ktermios *old_termios);
+
+static int  write(struct tty_struct *tty, const unsigned char *buf, int count);
+static int put_char(struct tty_struct *tty, unsigned char ch);
+static void send_xchar(struct tty_struct *tty, char ch);
+static void wait_until_sent(struct tty_struct *tty, int timeout);
+static int  write_room(struct tty_struct *tty);
+static void flush_chars(struct tty_struct *tty);
+static void flush_buffer(struct tty_struct *tty);
+static void tx_hold(struct tty_struct *tty);
+static void tx_release(struct tty_struct *tty);
+
+static int  ioctl(struct tty_struct *tty, unsigned int cmd, unsigned long arg);
+static int  chars_in_buffer(struct tty_struct *tty);
+static void throttle(struct tty_struct * tty);
+static void unthrottle(struct tty_struct * tty);
+static int set_break(struct tty_struct *tty, int break_state);
+
+#if SYNCLINK_GENERIC_HDLC
+#define dev_to_port(D) (dev_to_hdlc(D)->priv)
+static void hdlcdev_tx_done(SLMP_INFO *info);
+static void hdlcdev_rx(SLMP_INFO *info, char *buf, int size);
+static int  hdlcdev_init(SLMP_INFO *info);
+static void hdlcdev_exit(SLMP_INFO *info);
+#endif
+
+/* ioctl handlers */
+
+static int  get_stats(SLMP_INFO *info, struct mgsl_icount __user *user_icount);
+static int  get_params(SLMP_INFO *info, MGSL_PARAMS __user *params);
+static int  set_params(SLMP_INFO *info, MGSL_PARAMS __user *params);
+static int  get_txidle(SLMP_INFO *info, int __user *idle_mode);
+static int  set_txidle(SLMP_INFO *info, int idle_mode);
+static int  tx_enable(SLMP_INFO *info, int enable);
+static int  tx_abort(SLMP_INFO *info);
+static int  rx_enable(SLMP_INFO *info, int enable);
+static int  modem_input_wait(SLMP_INFO *info,int arg);
+static int  wait_mgsl_event(SLMP_INFO *info, int __user *mask_ptr);
+static int  tiocmget(struct tty_struct *tty);
+static int  tiocmset(struct tty_struct *tty,
+                       unsigned int set, unsigned int clear);
+static int  set_break(struct tty_struct *tty, int break_state);
+
+static void add_device(SLMP_INFO *info);
+static void device_init(int adapter_num, struct pci_dev *pdev);
+static int  claim_resources(SLMP_INFO *info);
+static void release_resources(SLMP_INFO *info);
+
+static int  startup(SLMP_INFO *info);
+static int  block_til_ready(struct tty_struct *tty, struct file * filp,SLMP_INFO *info);
+static int carrier_raised(struct tty_port *port);
+static void shutdown(SLMP_INFO *info);
+static void program_hw(SLMP_INFO *info);
+static void change_params(SLMP_INFO *info);
+
+static bool init_adapter(SLMP_INFO *info);
+static bool register_test(SLMP_INFO *info);
+static bool irq_test(SLMP_INFO *info);
+static bool loopback_test(SLMP_INFO *info);
+static int  adapter_test(SLMP_INFO *info);
+static bool memory_test(SLMP_INFO *info);
+
+static void reset_adapter(SLMP_INFO *info);
+static void reset_port(SLMP_INFO *info);
+static void async_mode(SLMP_INFO *info);
+static void hdlc_mode(SLMP_INFO *info);
+
+static void rx_stop(SLMP_INFO *info);
+static void rx_start(SLMP_INFO *info);
+static void rx_reset_buffers(SLMP_INFO *info);
+static void rx_free_frame_buffers(SLMP_INFO *info, unsigned int first, unsigned int last);
+static bool rx_get_frame(SLMP_INFO *info);
+
+static void tx_start(SLMP_INFO *info);
+static void tx_stop(SLMP_INFO *info);
+static void tx_load_fifo(SLMP_INFO *info);
+static void tx_set_idle(SLMP_INFO *info);
+static void tx_load_dma_buffer(SLMP_INFO *info, const char *buf, unsigned int count);
+
+static void get_signals(SLMP_INFO *info);
+static void set_signals(SLMP_INFO *info);
+static void enable_loopback(SLMP_INFO *info, int enable);
+static void set_rate(SLMP_INFO *info, u32 data_rate);
+
+static int  bh_action(SLMP_INFO *info);
+static void bh_handler(struct work_struct *work);
+static void bh_receive(SLMP_INFO *info);
+static void bh_transmit(SLMP_INFO *info);
+static void bh_status(SLMP_INFO *info);
+static void isr_timer(SLMP_INFO *info);
+static void isr_rxint(SLMP_INFO *info);
+static void isr_rxrdy(SLMP_INFO *info);
+static void isr_txint(SLMP_INFO *info);
+static void isr_txrdy(SLMP_INFO *info);
+static void isr_rxdmaok(SLMP_INFO *info);
+static void isr_rxdmaerror(SLMP_INFO *info);
+static void isr_txdmaok(SLMP_INFO *info);
+static void isr_txdmaerror(SLMP_INFO *info);
+static void isr_io_pin(SLMP_INFO *info, u16 status);
+
+static int  alloc_dma_bufs(SLMP_INFO *info);
+static void free_dma_bufs(SLMP_INFO *info);
+static int  alloc_buf_list(SLMP_INFO *info);
+static int  alloc_frame_bufs(SLMP_INFO *info, SCADESC *list, SCADESC_EX *list_ex,int count);
+static int  alloc_tmp_rx_buf(SLMP_INFO *info);
+static void free_tmp_rx_buf(SLMP_INFO *info);
+
+static void load_pci_memory(SLMP_INFO *info, char* dest, const char* src, unsigned short count);
+static void trace_block(SLMP_INFO *info, const char* data, int count, int xmit);
+static void tx_timeout(unsigned long context);
+static void status_timeout(unsigned long context);
+
+static unsigned char read_reg(SLMP_INFO *info, unsigned char addr);
+static void write_reg(SLMP_INFO *info, unsigned char addr, unsigned char val);
+static u16 read_reg16(SLMP_INFO *info, unsigned char addr);
+static void write_reg16(SLMP_INFO *info, unsigned char addr, u16 val);
+static unsigned char read_status_reg(SLMP_INFO * info);
+static void write_control_reg(SLMP_INFO * info);
+
+
+static unsigned char rx_active_fifo_level = 16;        // rx request FIFO activation level in bytes
+static unsigned char tx_active_fifo_level = 16;        // tx request FIFO activation level in bytes
+static unsigned char tx_negate_fifo_level = 32;        // tx request FIFO negation level in bytes
+
+static u32 misc_ctrl_value = 0x007e4040;
+static u32 lcr1_brdr_value = 0x00800028;
+
+static u32 read_ahead_count = 8;
+
+/* DPCR, DMA Priority Control
+ *
+ * 07..05  Not used, must be 0
+ * 04      BRC, bus release condition: 0=all transfers complete
+ *              1=release after 1 xfer on all channels
+ * 03      CCC, channel change condition: 0=every cycle
+ *              1=after each channel completes all xfers
+ * 02..00  PR<2..0>, priority 100=round robin
+ *
+ * 00000100 = 0x00
+ */
+static unsigned char dma_priority = 0x04;
+
+// Number of bytes that can be written to shared RAM
+// in a single write operation
+static u32 sca_pci_load_interval = 64;
+
+/*
+ * 1st function defined in .text section. Calling this function in
+ * init_module() followed by a breakpoint allows a remote debugger
+ * (gdb) to get the .text address for the add-symbol-file command.
+ * This allows remote debugging of dynamically loadable modules.
+ */
+static void* synclinkmp_get_text_ptr(void);
+static void* synclinkmp_get_text_ptr(void) {return synclinkmp_get_text_ptr;}
+
+static inline int sanity_check(SLMP_INFO *info,
+                              char *name, const char *routine)
+{
+#ifdef SANITY_CHECK
+       static const char *badmagic =
+               "Warning: bad magic number for synclinkmp_struct (%s) in %s\n";
+       static const char *badinfo =
+               "Warning: null synclinkmp_struct for (%s) in %s\n";
+
+       if (!info) {
+               printk(badinfo, name, routine);
+               return 1;
+       }
+       if (info->magic != MGSL_MAGIC) {
+               printk(badmagic, name, routine);
+               return 1;
+       }
+#else
+       if (!info)
+               return 1;
+#endif
+       return 0;
+}
+
+/**
+ * line discipline callback wrappers
+ *
+ * The wrappers maintain line discipline references
+ * while calling into the line discipline.
+ *
+ * ldisc_receive_buf  - pass receive data to line discipline
+ */
+
+static void ldisc_receive_buf(struct tty_struct *tty,
+                             const __u8 *data, char *flags, int count)
+{
+       struct tty_ldisc *ld;
+       if (!tty)
+               return;
+       ld = tty_ldisc_ref(tty);
+       if (ld) {
+               if (ld->ops->receive_buf)
+                       ld->ops->receive_buf(tty, data, flags, count);
+               tty_ldisc_deref(ld);
+       }
+}
+
+/* tty callbacks */
+
+static int install(struct tty_driver *driver, struct tty_struct *tty)
+{
+       SLMP_INFO *info;
+       int line = tty->index;
+
+       if (line >= synclinkmp_device_count) {
+               printk("%s(%d): open with invalid line #%d.\n",
+                       __FILE__,__LINE__,line);
+               return -ENODEV;
+       }
+
+       info = synclinkmp_device_list;
+       while (info && info->line != line)
+               info = info->next_device;
+       if (sanity_check(info, tty->name, "open"))
+               return -ENODEV;
+       if (info->init_error) {
+               printk("%s(%d):%s device is not allocated, init error=%d\n",
+                       __FILE__, __LINE__, info->device_name,
+                       info->init_error);
+               return -ENODEV;
+       }
+
+       tty->driver_data = info;
+
+       return tty_port_install(&info->port, driver, tty);
+}
+
+/* Called when a port is opened.  Init and enable port.
+ */
+static int open(struct tty_struct *tty, struct file *filp)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+       int retval;
+
+       info->port.tty = tty;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s open(), old ref count = %d\n",
+                        __FILE__,__LINE__,tty->driver->name, info->port.count);
+
+       /* If port is closing, signal caller to try again */
+       if (info->port.flags & ASYNC_CLOSING){
+               wait_event_interruptible_tty(tty, info->port.close_wait,
+                                            !(info->port.flags & ASYNC_CLOSING));
+               retval = ((info->port.flags & ASYNC_HUP_NOTIFY) ?
+                       -EAGAIN : -ERESTARTSYS);
+               goto cleanup;
+       }
+
+       info->port.low_latency = (info->port.flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+
+       spin_lock_irqsave(&info->netlock, flags);
+       if (info->netcount) {
+               retval = -EBUSY;
+               spin_unlock_irqrestore(&info->netlock, flags);
+               goto cleanup;
+       }
+       info->port.count++;
+       spin_unlock_irqrestore(&info->netlock, flags);
+
+       if (info->port.count == 1) {
+               /* 1st open on this device, init hardware */
+               retval = startup(info);
+               if (retval < 0)
+                       goto cleanup;
+       }
+
+       retval = block_til_ready(tty, filp, info);
+       if (retval) {
+               if (debug_level >= DEBUG_LEVEL_INFO)
+                       printk("%s(%d):%s block_til_ready() returned %d\n",
+                                __FILE__,__LINE__, info->device_name, retval);
+               goto cleanup;
+       }
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s open() success\n",
+                        __FILE__,__LINE__, info->device_name);
+       retval = 0;
+
+cleanup:
+       if (retval) {
+               if (tty->count == 1)
+                       info->port.tty = NULL; /* tty layer will release tty struct */
+               if(info->port.count)
+                       info->port.count--;
+       }
+
+       return retval;
+}
+
+/* Called when port is closed. Wait for remaining data to be
+ * sent. Disable port and free resources.
+ */
+static void close(struct tty_struct *tty, struct file *filp)
+{
+       SLMP_INFO * info = tty->driver_data;
+
+       if (sanity_check(info, tty->name, "close"))
+               return;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s close() entry, count=%d\n",
+                        __FILE__,__LINE__, info->device_name, info->port.count);
+
+       if (tty_port_close_start(&info->port, tty, filp) == 0)
+               goto cleanup;
+
+       mutex_lock(&info->port.mutex);
+       if (info->port.flags & ASYNC_INITIALIZED)
+               wait_until_sent(tty, info->timeout);
+
+       flush_buffer(tty);
+       tty_ldisc_flush(tty);
+       shutdown(info);
+       mutex_unlock(&info->port.mutex);
+
+       tty_port_close_end(&info->port, tty);
+       info->port.tty = NULL;
+cleanup:
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s close() exit, count=%d\n", __FILE__,__LINE__,
+                       tty->driver->name, info->port.count);
+}
+
+/* Called by tty_hangup() when a hangup is signaled.
+ * This is the same as closing all open descriptors for the port.
+ */
+static void hangup(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s hangup()\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       if (sanity_check(info, tty->name, "hangup"))
+               return;
+
+       mutex_lock(&info->port.mutex);
+       flush_buffer(tty);
+       shutdown(info);
+
+       spin_lock_irqsave(&info->port.lock, flags);
+       info->port.count = 0;
+       info->port.flags &= ~ASYNC_NORMAL_ACTIVE;
+       info->port.tty = NULL;
+       spin_unlock_irqrestore(&info->port.lock, flags);
+       mutex_unlock(&info->port.mutex);
+
+       wake_up_interruptible(&info->port.open_wait);
+}
+
+/* Set new termios settings
+ */
+static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s set_termios()\n", __FILE__,__LINE__,
+                       tty->driver->name );
+
+       change_params(info);
+
+       /* Handle transition to B0 status */
+       if (old_termios->c_cflag & CBAUD &&
+           !(tty->termios.c_cflag & CBAUD)) {
+               info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+               spin_lock_irqsave(&info->lock,flags);
+               set_signals(info);
+               spin_unlock_irqrestore(&info->lock,flags);
+       }
+
+       /* Handle transition away from B0 status */
+       if (!(old_termios->c_cflag & CBAUD) &&
+           tty->termios.c_cflag & CBAUD) {
+               info->serial_signals |= SerialSignal_DTR;
+               if (!(tty->termios.c_cflag & CRTSCTS) ||
+                   !test_bit(TTY_THROTTLED, &tty->flags)) {
+                       info->serial_signals |= SerialSignal_RTS;
+               }
+               spin_lock_irqsave(&info->lock,flags);
+               set_signals(info);
+               spin_unlock_irqrestore(&info->lock,flags);
+       }
+
+       /* Handle turning off CRTSCTS */
+       if (old_termios->c_cflag & CRTSCTS &&
+           !(tty->termios.c_cflag & CRTSCTS)) {
+               tty->hw_stopped = 0;
+               tx_release(tty);
+       }
+}
+
+/* Send a block of data
+ *
+ * Arguments:
+ *
+ *     tty             pointer to tty information structure
+ *     buf             pointer to buffer containing send data
+ *     count           size of send data in bytes
+ *
+ * Return Value:       number of characters written
+ */
+static int write(struct tty_struct *tty,
+                const unsigned char *buf, int count)
+{
+       int     c, ret = 0;
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s write() count=%d\n",
+                      __FILE__,__LINE__,info->device_name,count);
+
+       if (sanity_check(info, tty->name, "write"))
+               goto cleanup;
+
+       if (!info->tx_buf)
+               goto cleanup;
+
+       if (info->params.mode == MGSL_MODE_HDLC) {
+               if (count > info->max_frame_size) {
+                       ret = -EIO;
+                       goto cleanup;
+               }
+               if (info->tx_active)
+                       goto cleanup;
+               if (info->tx_count) {
+                       /* send accumulated data from send_char() calls */
+                       /* as frame and wait before accepting more data. */
+                       tx_load_dma_buffer(info, info->tx_buf, info->tx_count);
+                       goto start;
+               }
+               ret = info->tx_count = count;
+               tx_load_dma_buffer(info, buf, count);
+               goto start;
+       }
+
+       for (;;) {
+               c = min_t(int, count,
+                       min(info->max_frame_size - info->tx_count - 1,
+                           info->max_frame_size - info->tx_put));
+               if (c <= 0)
+                       break;
+                       
+               memcpy(info->tx_buf + info->tx_put, buf, c);
+
+               spin_lock_irqsave(&info->lock,flags);
+               info->tx_put += c;
+               if (info->tx_put >= info->max_frame_size)
+                       info->tx_put -= info->max_frame_size;
+               info->tx_count += c;
+               spin_unlock_irqrestore(&info->lock,flags);
+
+               buf += c;
+               count -= c;
+               ret += c;
+       }
+
+       if (info->params.mode == MGSL_MODE_HDLC) {
+               if (count) {
+                       ret = info->tx_count = 0;
+                       goto cleanup;
+               }
+               tx_load_dma_buffer(info, info->tx_buf, info->tx_count);
+       }
+start:
+       if (info->tx_count && !tty->stopped && !tty->hw_stopped) {
+               spin_lock_irqsave(&info->lock,flags);
+               if (!info->tx_active)
+                       tx_start(info);
+               spin_unlock_irqrestore(&info->lock,flags);
+       }
+
+cleanup:
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk( "%s(%d):%s write() returning=%d\n",
+                       __FILE__,__LINE__,info->device_name,ret);
+       return ret;
+}
+
+/* Add a character to the transmit buffer.
+ */
+static int put_char(struct tty_struct *tty, unsigned char ch)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+       int ret = 0;
+
+       if ( debug_level >= DEBUG_LEVEL_INFO ) {
+               printk( "%s(%d):%s put_char(%d)\n",
+                       __FILE__,__LINE__,info->device_name,ch);
+       }
+
+       if (sanity_check(info, tty->name, "put_char"))
+               return 0;
+
+       if (!info->tx_buf)
+               return 0;
+
+       spin_lock_irqsave(&info->lock,flags);
+
+       if ( (info->params.mode != MGSL_MODE_HDLC) ||
+            !info->tx_active ) {
+
+               if (info->tx_count < info->max_frame_size - 1) {
+                       info->tx_buf[info->tx_put++] = ch;
+                       if (info->tx_put >= info->max_frame_size)
+                               info->tx_put -= info->max_frame_size;
+                       info->tx_count++;
+                       ret = 1;
+               }
+       }
+
+       spin_unlock_irqrestore(&info->lock,flags);
+       return ret;
+}
+
+/* Send a high-priority XON/XOFF character
+ */
+static void send_xchar(struct tty_struct *tty, char ch)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s send_xchar(%d)\n",
+                        __FILE__,__LINE__, info->device_name, ch );
+
+       if (sanity_check(info, tty->name, "send_xchar"))
+               return;
+
+       info->x_char = ch;
+       if (ch) {
+               /* Make sure transmit interrupts are on */
+               spin_lock_irqsave(&info->lock,flags);
+               if (!info->tx_enabled)
+                       tx_start(info);
+               spin_unlock_irqrestore(&info->lock,flags);
+       }
+}
+
+/* Wait until the transmitter is empty.
+ */
+static void wait_until_sent(struct tty_struct *tty, int timeout)
+{
+       SLMP_INFO * info = tty->driver_data;
+       unsigned long orig_jiffies, char_time;
+
+       if (!info )
+               return;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s wait_until_sent() entry\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       if (sanity_check(info, tty->name, "wait_until_sent"))
+               return;
+
+       if (!test_bit(ASYNCB_INITIALIZED, &info->port.flags))
+               goto exit;
+
+       orig_jiffies = jiffies;
+
+       /* Set check interval to 1/5 of estimated time to
+        * send a character, and make it at least 1. The check
+        * interval should also be less than the timeout.
+        * Note: use tight timings here to satisfy the NIST-PCTS.
+        */
+
+       if ( info->params.data_rate ) {
+               char_time = info->timeout/(32 * 5);
+               if (!char_time)
+                       char_time++;
+       } else
+               char_time = 1;
+
+       if (timeout)
+               char_time = min_t(unsigned long, char_time, timeout);
+
+       if ( info->params.mode == MGSL_MODE_HDLC ) {
+               while (info->tx_active) {
+                       msleep_interruptible(jiffies_to_msecs(char_time));
+                       if (signal_pending(current))
+                               break;
+                       if (timeout && time_after(jiffies, orig_jiffies + timeout))
+                               break;
+               }
+       } else {
+               /*
+                * TODO: determine if there is something similar to USC16C32
+                *       TXSTATUS_ALL_SENT status
+                */
+               while ( info->tx_active && info->tx_enabled) {
+                       msleep_interruptible(jiffies_to_msecs(char_time));
+                       if (signal_pending(current))
+                               break;
+                       if (timeout && time_after(jiffies, orig_jiffies + timeout))
+                               break;
+               }
+       }
+
+exit:
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s wait_until_sent() exit\n",
+                        __FILE__,__LINE__, info->device_name );
+}
+
+/* Return the count of free bytes in transmit buffer
+ */
+static int write_room(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       int ret;
+
+       if (sanity_check(info, tty->name, "write_room"))
+               return 0;
+
+       if (info->params.mode == MGSL_MODE_HDLC) {
+               ret = (info->tx_active) ? 0 : HDLC_MAX_FRAME_SIZE;
+       } else {
+               ret = info->max_frame_size - info->tx_count - 1;
+               if (ret < 0)
+                       ret = 0;
+       }
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s write_room()=%d\n",
+                      __FILE__, __LINE__, info->device_name, ret);
+
+       return ret;
+}
+
+/* enable transmitter and send remaining buffered characters
+ */
+static void flush_chars(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk( "%s(%d):%s flush_chars() entry tx_count=%d\n",
+                       __FILE__,__LINE__,info->device_name,info->tx_count);
+
+       if (sanity_check(info, tty->name, "flush_chars"))
+               return;
+
+       if (info->tx_count <= 0 || tty->stopped || tty->hw_stopped ||
+           !info->tx_buf)
+               return;
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk( "%s(%d):%s flush_chars() entry, starting transmitter\n",
+                       __FILE__,__LINE__,info->device_name );
+
+       spin_lock_irqsave(&info->lock,flags);
+
+       if (!info->tx_active) {
+               if ( (info->params.mode == MGSL_MODE_HDLC) &&
+                       info->tx_count ) {
+                       /* operating in synchronous (frame oriented) mode */
+                       /* copy data from circular tx_buf to */
+                       /* transmit DMA buffer. */
+                       tx_load_dma_buffer(info,
+                                info->tx_buf,info->tx_count);
+               }
+               tx_start(info);
+       }
+
+       spin_unlock_irqrestore(&info->lock,flags);
+}
+
+/* Discard all data in the send buffer
+ */
+static void flush_buffer(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s flush_buffer() entry\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       if (sanity_check(info, tty->name, "flush_buffer"))
+               return;
+
+       spin_lock_irqsave(&info->lock,flags);
+       info->tx_count = info->tx_put = info->tx_get = 0;
+       del_timer(&info->tx_timer);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       tty_wakeup(tty);
+}
+
+/* throttle (stop) transmitter
+ */
+static void tx_hold(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (sanity_check(info, tty->name, "tx_hold"))
+               return;
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk("%s(%d):%s tx_hold()\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       spin_lock_irqsave(&info->lock,flags);
+       if (info->tx_enabled)
+               tx_stop(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+}
+
+/* release (start) transmitter
+ */
+static void tx_release(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (sanity_check(info, tty->name, "tx_release"))
+               return;
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk("%s(%d):%s tx_release()\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       spin_lock_irqsave(&info->lock,flags);
+       if (!info->tx_enabled)
+               tx_start(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+}
+
+/* Service an IOCTL request
+ *
+ * Arguments:
+ *
+ *     tty     pointer to tty instance data
+ *     cmd     IOCTL command code
+ *     arg     command argument/context
+ *
+ * Return Value:       0 if success, otherwise error code
+ */
+static int ioctl(struct tty_struct *tty,
+                unsigned int cmd, unsigned long arg)
+{
+       SLMP_INFO *info = tty->driver_data;
+       void __user *argp = (void __user *)arg;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s ioctl() cmd=%08X\n", __FILE__,__LINE__,
+                       info->device_name, cmd );
+
+       if (sanity_check(info, tty->name, "ioctl"))
+               return -ENODEV;
+
+       if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
+           (cmd != TIOCMIWAIT)) {
+               if (tty->flags & (1 << TTY_IO_ERROR))
+                   return -EIO;
+       }
+
+       switch (cmd) {
+       case MGSL_IOCGPARAMS:
+               return get_params(info, argp);
+       case MGSL_IOCSPARAMS:
+               return set_params(info, argp);
+       case MGSL_IOCGTXIDLE:
+               return get_txidle(info, argp);
+       case MGSL_IOCSTXIDLE:
+               return set_txidle(info, (int)arg);
+       case MGSL_IOCTXENABLE:
+               return tx_enable(info, (int)arg);
+       case MGSL_IOCRXENABLE:
+               return rx_enable(info, (int)arg);
+       case MGSL_IOCTXABORT:
+               return tx_abort(info);
+       case MGSL_IOCGSTATS:
+               return get_stats(info, argp);
+       case MGSL_IOCWAITEVENT:
+               return wait_mgsl_event(info, argp);
+       case MGSL_IOCLOOPTXDONE:
+               return 0; // TODO: Not supported, need to document
+               /* Wait for modem input (DCD,RI,DSR,CTS) change
+                * as specified by mask in arg (TIOCM_RNG/DSR/CD/CTS)
+                */
+       case TIOCMIWAIT:
+               return modem_input_wait(info,(int)arg);
+               
+               /*
+                * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
+                * Return: write counters to the user passed counter struct
+                * NB: both 1->0 and 0->1 transitions are counted except for
+                *     RI where only 0->1 is counted.
+                */
+       default:
+               return -ENOIOCTLCMD;
+       }
+       return 0;
+}
+
+static int get_icount(struct tty_struct *tty,
+                               struct serial_icounter_struct *icount)
+{
+       SLMP_INFO *info = tty->driver_data;
+       struct mgsl_icount cnow;        /* kernel counter temps */
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->lock,flags);
+       cnow = info->icount;
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       icount->cts = cnow.cts;
+       icount->dsr = cnow.dsr;
+       icount->rng = cnow.rng;
+       icount->dcd = cnow.dcd;
+       icount->rx = cnow.rx;
+       icount->tx = cnow.tx;
+       icount->frame = cnow.frame;
+       icount->overrun = cnow.overrun;
+       icount->parity = cnow.parity;
+       icount->brk = cnow.brk;
+       icount->buf_overrun = cnow.buf_overrun;
+
+       return 0;
+}
+
+/*
+ * /proc fs routines....
+ */
+
+static inline void line_info(struct seq_file *m, SLMP_INFO *info)
+{
+       char    stat_buf[30];
+       unsigned long flags;
+
+       seq_printf(m, "%s: SCABase=%08x Mem=%08X StatusControl=%08x LCR=%08X\n"
+                      "\tIRQ=%d MaxFrameSize=%u\n",
+               info->device_name,
+               info->phys_sca_base,
+               info->phys_memory_base,
+               info->phys_statctrl_base,
+               info->phys_lcr_base,
+               info->irq_level,
+               info->max_frame_size );
+
+       /* output current serial signal states */
+       spin_lock_irqsave(&info->lock,flags);
+       get_signals(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       stat_buf[0] = 0;
+       stat_buf[1] = 0;
+       if (info->serial_signals & SerialSignal_RTS)
+               strcat(stat_buf, "|RTS");
+       if (info->serial_signals & SerialSignal_CTS)
+               strcat(stat_buf, "|CTS");
+       if (info->serial_signals & SerialSignal_DTR)
+               strcat(stat_buf, "|DTR");
+       if (info->serial_signals & SerialSignal_DSR)
+               strcat(stat_buf, "|DSR");
+       if (info->serial_signals & SerialSignal_DCD)
+               strcat(stat_buf, "|CD");
+       if (info->serial_signals & SerialSignal_RI)
+               strcat(stat_buf, "|RI");
+
+       if (info->params.mode == MGSL_MODE_HDLC) {
+               seq_printf(m, "\tHDLC txok:%d rxok:%d",
+                             info->icount.txok, info->icount.rxok);
+               if (info->icount.txunder)
+                       seq_printf(m, " txunder:%d", info->icount.txunder);
+               if (info->icount.txabort)
+                       seq_printf(m, " txabort:%d", info->icount.txabort);
+               if (info->icount.rxshort)
+                       seq_printf(m, " rxshort:%d", info->icount.rxshort);
+               if (info->icount.rxlong)
+                       seq_printf(m, " rxlong:%d", info->icount.rxlong);
+               if (info->icount.rxover)
+                       seq_printf(m, " rxover:%d", info->icount.rxover);
+               if (info->icount.rxcrc)
+                       seq_printf(m, " rxlong:%d", info->icount.rxcrc);
+       } else {
+               seq_printf(m, "\tASYNC tx:%d rx:%d",
+                             info->icount.tx, info->icount.rx);
+               if (info->icount.frame)
+                       seq_printf(m, " fe:%d", info->icount.frame);
+               if (info->icount.parity)
+                       seq_printf(m, " pe:%d", info->icount.parity);
+               if (info->icount.brk)
+                       seq_printf(m, " brk:%d", info->icount.brk);
+               if (info->icount.overrun)
+                       seq_printf(m, " oe:%d", info->icount.overrun);
+       }
+
+       /* Append serial signal status to end */
+       seq_printf(m, " %s\n", stat_buf+1);
+
+       seq_printf(m, "\ttxactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
+        info->tx_active,info->bh_requested,info->bh_running,
+        info->pending_bh);
+}
+
+/* Called to print information about devices
+ */
+static int synclinkmp_proc_show(struct seq_file *m, void *v)
+{
+       SLMP_INFO *info;
+
+       seq_printf(m, "synclinkmp driver:%s\n", driver_version);
+
+       info = synclinkmp_device_list;
+       while( info ) {
+               line_info(m, info);
+               info = info->next_device;
+       }
+       return 0;
+}
+
+static int synclinkmp_proc_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, synclinkmp_proc_show, NULL);
+}
+
+static const struct file_operations synclinkmp_proc_fops = {
+       .owner          = THIS_MODULE,
+       .open           = synclinkmp_proc_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
+/* Return the count of bytes in transmit buffer
+ */
+static int chars_in_buffer(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+
+       if (sanity_check(info, tty->name, "chars_in_buffer"))
+               return 0;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s chars_in_buffer()=%d\n",
+                      __FILE__, __LINE__, info->device_name, info->tx_count);
+
+       return info->tx_count;
+}
+
+/* Signal remote device to throttle send data (our receive data)
+ */
+static void throttle(struct tty_struct * tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s throttle() entry\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       if (sanity_check(info, tty->name, "throttle"))
+               return;
+
+       if (I_IXOFF(tty))
+               send_xchar(tty, STOP_CHAR(tty));
+
+       if (tty->termios.c_cflag & CRTSCTS) {
+               spin_lock_irqsave(&info->lock,flags);
+               info->serial_signals &= ~SerialSignal_RTS;
+               set_signals(info);
+               spin_unlock_irqrestore(&info->lock,flags);
+       }
+}
+
+/* Signal remote device to stop throttling send data (our receive data)
+ */
+static void unthrottle(struct tty_struct * tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s unthrottle() entry\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       if (sanity_check(info, tty->name, "unthrottle"))
+               return;
+
+       if (I_IXOFF(tty)) {
+               if (info->x_char)
+                       info->x_char = 0;
+               else
+                       send_xchar(tty, START_CHAR(tty));
+       }
+
+       if (tty->termios.c_cflag & CRTSCTS) {
+               spin_lock_irqsave(&info->lock,flags);
+               info->serial_signals |= SerialSignal_RTS;
+               set_signals(info);
+               spin_unlock_irqrestore(&info->lock,flags);
+       }
+}
+
+/* set or clear transmit break condition
+ * break_state -1=set break condition, 0=clear
+ */
+static int set_break(struct tty_struct *tty, int break_state)
+{
+       unsigned char RegValue;
+       SLMP_INFO * info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s set_break(%d)\n",
+                        __FILE__,__LINE__, info->device_name, break_state);
+
+       if (sanity_check(info, tty->name, "set_break"))
+               return -EINVAL;
+
+       spin_lock_irqsave(&info->lock,flags);
+       RegValue = read_reg(info, CTL);
+       if (break_state == -1)
+               RegValue |= BIT3;
+       else
+               RegValue &= ~BIT3;
+       write_reg(info, CTL, RegValue);
+       spin_unlock_irqrestore(&info->lock,flags);
+       return 0;
+}
+
+#if SYNCLINK_GENERIC_HDLC
+
+/**
+ * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
+ * set encoding and frame check sequence (FCS) options
+ *
+ * dev       pointer to network device structure
+ * encoding  serial encoding setting
+ * parity    FCS setting
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
+                         unsigned short parity)
+{
+       SLMP_INFO *info = dev_to_port(dev);
+       unsigned char  new_encoding;
+       unsigned short new_crctype;
+
+       /* return error if TTY interface open */
+       if (info->port.count)
+               return -EBUSY;
+
+       switch (encoding)
+       {
+       case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
+       case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
+       case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
+       case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
+       case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
+       default: return -EINVAL;
+       }
+
+       switch (parity)
+       {
+       case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
+       case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
+       case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
+       default: return -EINVAL;
+       }
+
+       info->params.encoding = new_encoding;
+       info->params.crc_type = new_crctype;
+
+       /* if network interface up, reprogram hardware */
+       if (info->netcount)
+               program_hw(info);
+
+       return 0;
+}
+
+/**
+ * called by generic HDLC layer to send frame
+ *
+ * skb  socket buffer containing HDLC frame
+ * dev  pointer to network device structure
+ */
+static netdev_tx_t hdlcdev_xmit(struct sk_buff *skb,
+                                     struct net_device *dev)
+{
+       SLMP_INFO *info = dev_to_port(dev);
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk(KERN_INFO "%s:hdlc_xmit(%s)\n",__FILE__,dev->name);
+
+       /* stop sending until this frame completes */
+       netif_stop_queue(dev);
+
+       /* copy data to device buffers */
+       info->tx_count = skb->len;
+       tx_load_dma_buffer(info, skb->data, skb->len);
+
+       /* update network statistics */
+       dev->stats.tx_packets++;
+       dev->stats.tx_bytes += skb->len;
+
+       /* done with socket buffer, so free it */
+       dev_kfree_skb(skb);
+
+       /* save start time for transmit timeout detection */
+       dev->trans_start = jiffies;
+
+       /* start hardware transmitter if necessary */
+       spin_lock_irqsave(&info->lock,flags);
+       if (!info->tx_active)
+               tx_start(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       return NETDEV_TX_OK;
+}
+
+/**
+ * called by network layer when interface enabled
+ * claim resources and initialize hardware
+ *
+ * dev  pointer to network device structure
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_open(struct net_device *dev)
+{
+       SLMP_INFO *info = dev_to_port(dev);
+       int rc;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s:hdlcdev_open(%s)\n",__FILE__,dev->name);
+
+       /* generic HDLC layer open processing */
+       if ((rc = hdlc_open(dev)))
+               return rc;
+
+       /* arbitrate between network and tty opens */
+       spin_lock_irqsave(&info->netlock, flags);
+       if (info->port.count != 0 || info->netcount != 0) {
+               printk(KERN_WARNING "%s: hdlc_open returning busy\n", dev->name);
+               spin_unlock_irqrestore(&info->netlock, flags);
+               return -EBUSY;
+       }
+       info->netcount=1;
+       spin_unlock_irqrestore(&info->netlock, flags);
+
+       /* claim resources and init adapter */
+       if ((rc = startup(info)) != 0) {
+               spin_lock_irqsave(&info->netlock, flags);
+               info->netcount=0;
+               spin_unlock_irqrestore(&info->netlock, flags);
+               return rc;
+       }
+
+       /* assert RTS and DTR, apply hardware settings */
+       info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
+       program_hw(info);
+
+       /* enable network layer transmit */
+       dev->trans_start = jiffies;
+       netif_start_queue(dev);
+
+       /* inform generic HDLC layer of current DCD status */
+       spin_lock_irqsave(&info->lock, flags);
+       get_signals(info);
+       spin_unlock_irqrestore(&info->lock, flags);
+       if (info->serial_signals & SerialSignal_DCD)
+               netif_carrier_on(dev);
+       else
+               netif_carrier_off(dev);
+       return 0;
+}
+
+/**
+ * called by network layer when interface is disabled
+ * shutdown hardware and release resources
+ *
+ * dev  pointer to network device structure
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_close(struct net_device *dev)
+{
+       SLMP_INFO *info = dev_to_port(dev);
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s:hdlcdev_close(%s)\n",__FILE__,dev->name);
+
+       netif_stop_queue(dev);
+
+       /* shutdown adapter and release resources */
+       shutdown(info);
+
+       hdlc_close(dev);
+
+       spin_lock_irqsave(&info->netlock, flags);
+       info->netcount=0;
+       spin_unlock_irqrestore(&info->netlock, flags);
+
+       return 0;
+}
+
+/**
+ * called by network layer to process IOCTL call to network device
+ *
+ * dev  pointer to network device structure
+ * ifr  pointer to network interface request structure
+ * cmd  IOCTL command code
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+       const size_t size = sizeof(sync_serial_settings);
+       sync_serial_settings new_line;
+       sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
+       SLMP_INFO *info = dev_to_port(dev);
+       unsigned int flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s:hdlcdev_ioctl(%s)\n",__FILE__,dev->name);
+
+       /* return error if TTY interface open */
+       if (info->port.count)
+               return -EBUSY;
+
+       if (cmd != SIOCWANDEV)
+               return hdlc_ioctl(dev, ifr, cmd);
+
+       switch(ifr->ifr_settings.type) {
+       case IF_GET_IFACE: /* return current sync_serial_settings */
+
+               ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
+               if (ifr->ifr_settings.size < size) {
+                       ifr->ifr_settings.size = size; /* data size wanted */
+                       return -ENOBUFS;
+               }
+
+               flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+                                             HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+                                             HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+                                             HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
+
+               memset(&new_line, 0, sizeof(new_line));
+               switch (flags){
+               case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
+               case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
+               case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
+               case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
+               default: new_line.clock_type = CLOCK_DEFAULT;
+               }
+
+               new_line.clock_rate = info->params.clock_speed;
+               new_line.loopback   = info->params.loopback ? 1:0;
+
+               if (copy_to_user(line, &new_line, size))
+                       return -EFAULT;
+               return 0;
+
+       case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
+
+               if(!capable(CAP_NET_ADMIN))
+                       return -EPERM;
+               if (copy_from_user(&new_line, line, size))
+                       return -EFAULT;
+
+               switch (new_line.clock_type)
+               {
+               case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
+               case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
+               case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
+               case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
+               case CLOCK_DEFAULT:  flags = info->params.flags &
+                                            (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+                                             HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+                                             HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+                                             HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
+               default: return -EINVAL;
+               }
+
+               if (new_line.loopback != 0 && new_line.loopback != 1)
+                       return -EINVAL;
+
+               info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+                                       HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+                                       HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+                                       HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
+               info->params.flags |= flags;
+
+               info->params.loopback = new_line.loopback;
+
+               if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
+                       info->params.clock_speed = new_line.clock_rate;
+               else
+                       info->params.clock_speed = 0;
+
+               /* if network interface up, reprogram hardware */
+               if (info->netcount)
+                       program_hw(info);
+               return 0;
+
+       default:
+               return hdlc_ioctl(dev, ifr, cmd);
+       }
+}
+
+/**
+ * called by network layer when transmit timeout is detected
+ *
+ * dev  pointer to network device structure
+ */
+static void hdlcdev_tx_timeout(struct net_device *dev)
+{
+       SLMP_INFO *info = dev_to_port(dev);
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("hdlcdev_tx_timeout(%s)\n",dev->name);
+
+       dev->stats.tx_errors++;
+       dev->stats.tx_aborted_errors++;
+
+       spin_lock_irqsave(&info->lock,flags);
+       tx_stop(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       netif_wake_queue(dev);
+}
+
+/**
+ * called by device driver when transmit completes
+ * reenable network layer transmit if stopped
+ *
+ * info  pointer to device instance information
+ */
+static void hdlcdev_tx_done(SLMP_INFO *info)
+{
+       if (netif_queue_stopped(info->netdev))
+               netif_wake_queue(info->netdev);
+}
+
+/**
+ * called by device driver when frame received
+ * pass frame to network layer
+ *
+ * info  pointer to device instance information
+ * buf   pointer to buffer contianing frame data
+ * size  count of data bytes in buf
+ */
+static void hdlcdev_rx(SLMP_INFO *info, char *buf, int size)
+{
+       struct sk_buff *skb = dev_alloc_skb(size);
+       struct net_device *dev = info->netdev;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("hdlcdev_rx(%s)\n",dev->name);
+
+       if (skb == NULL) {
+               printk(KERN_NOTICE "%s: can't alloc skb, dropping packet\n",
+                      dev->name);
+               dev->stats.rx_dropped++;
+               return;
+       }
+
+       memcpy(skb_put(skb, size), buf, size);
+
+       skb->protocol = hdlc_type_trans(skb, dev);
+
+       dev->stats.rx_packets++;
+       dev->stats.rx_bytes += size;
+
+       netif_rx(skb);
+}
+
+static const struct net_device_ops hdlcdev_ops = {
+       .ndo_open       = hdlcdev_open,
+       .ndo_stop       = hdlcdev_close,
+       .ndo_change_mtu = hdlc_change_mtu,
+       .ndo_start_xmit = hdlc_start_xmit,
+       .ndo_do_ioctl   = hdlcdev_ioctl,
+       .ndo_tx_timeout = hdlcdev_tx_timeout,
+};
+
+/**
+ * called by device driver when adding device instance
+ * do generic HDLC initialization
+ *
+ * info  pointer to device instance information
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_init(SLMP_INFO *info)
+{
+       int rc;
+       struct net_device *dev;
+       hdlc_device *hdlc;
+
+       /* allocate and initialize network and HDLC layer objects */
+
+       if (!(dev = alloc_hdlcdev(info))) {
+               printk(KERN_ERR "%s:hdlc device allocation failure\n",__FILE__);
+               return -ENOMEM;
+       }
+
+       /* for network layer reporting purposes only */
+       dev->mem_start = info->phys_sca_base;
+       dev->mem_end   = info->phys_sca_base + SCA_BASE_SIZE - 1;
+       dev->irq       = info->irq_level;
+
+       /* network layer callbacks and settings */
+       dev->netdev_ops     = &hdlcdev_ops;
+       dev->watchdog_timeo = 10 * HZ;
+       dev->tx_queue_len   = 50;
+
+       /* generic HDLC layer callbacks and settings */
+       hdlc         = dev_to_hdlc(dev);
+       hdlc->attach = hdlcdev_attach;
+       hdlc->xmit   = hdlcdev_xmit;
+
+       /* register objects with HDLC layer */
+       if ((rc = register_hdlc_device(dev))) {
+               printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
+               free_netdev(dev);
+               return rc;
+       }
+
+       info->netdev = dev;
+       return 0;
+}
+
+/**
+ * called by device driver when removing device instance
+ * do generic HDLC cleanup
+ *
+ * info  pointer to device instance information
+ */
+static void hdlcdev_exit(SLMP_INFO *info)
+{
+       unregister_hdlc_device(info->netdev);
+       free_netdev(info->netdev);
+       info->netdev = NULL;
+}
+
+#endif /* CONFIG_HDLC */
+
+
+/* Return next bottom half action to perform.
+ * Return Value:       BH action code or 0 if nothing to do.
+ */
+static int bh_action(SLMP_INFO *info)
+{
+       unsigned long flags;
+       int rc = 0;
+
+       spin_lock_irqsave(&info->lock,flags);
+
+       if (info->pending_bh & BH_RECEIVE) {
+               info->pending_bh &= ~BH_RECEIVE;
+               rc = BH_RECEIVE;
+       } else if (info->pending_bh & BH_TRANSMIT) {
+               info->pending_bh &= ~BH_TRANSMIT;
+               rc = BH_TRANSMIT;
+       } else if (info->pending_bh & BH_STATUS) {
+               info->pending_bh &= ~BH_STATUS;
+               rc = BH_STATUS;
+       }
+
+       if (!rc) {
+               /* Mark BH routine as complete */
+               info->bh_running = false;
+               info->bh_requested = false;
+       }
+
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       return rc;
+}
+
+/* Perform bottom half processing of work items queued by ISR.
+ */
+static void bh_handler(struct work_struct *work)
+{
+       SLMP_INFO *info = container_of(work, SLMP_INFO, task);
+       int action;
+
+       if ( debug_level >= DEBUG_LEVEL_BH )
+               printk( "%s(%d):%s bh_handler() entry\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       info->bh_running = true;
+
+       while((action = bh_action(info)) != 0) {
+
+               /* Process work item */
+               if ( debug_level >= DEBUG_LEVEL_BH )
+                       printk( "%s(%d):%s bh_handler() work item action=%d\n",
+                               __FILE__,__LINE__,info->device_name, action);
+
+               switch (action) {
+
+               case BH_RECEIVE:
+                       bh_receive(info);
+                       break;
+               case BH_TRANSMIT:
+                       bh_transmit(info);
+                       break;
+               case BH_STATUS:
+                       bh_status(info);
+                       break;
+               default:
+                       /* unknown work item ID */
+                       printk("%s(%d):%s Unknown work item ID=%08X!\n",
+                               __FILE__,__LINE__,info->device_name,action);
+                       break;
+               }
+       }
+
+       if ( debug_level >= DEBUG_LEVEL_BH )
+               printk( "%s(%d):%s bh_handler() exit\n",
+                       __FILE__,__LINE__,info->device_name);
+}
+
+static void bh_receive(SLMP_INFO *info)
+{
+       if ( debug_level >= DEBUG_LEVEL_BH )
+               printk( "%s(%d):%s bh_receive()\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       while( rx_get_frame(info) );
+}
+
+static void bh_transmit(SLMP_INFO *info)
+{
+       struct tty_struct *tty = info->port.tty;
+
+       if ( debug_level >= DEBUG_LEVEL_BH )
+               printk( "%s(%d):%s bh_transmit() entry\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       if (tty)
+               tty_wakeup(tty);
+}
+
+static void bh_status(SLMP_INFO *info)
+{
+       if ( debug_level >= DEBUG_LEVEL_BH )
+               printk( "%s(%d):%s bh_status() entry\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       info->ri_chkcount = 0;
+       info->dsr_chkcount = 0;
+       info->dcd_chkcount = 0;
+       info->cts_chkcount = 0;
+}
+
+static void isr_timer(SLMP_INFO * info)
+{
+       unsigned char timer = (info->port_num & 1) ? TIMER2 : TIMER0;
+
+       /* IER2<7..4> = timer<3..0> interrupt enables (0=disabled) */
+       write_reg(info, IER2, 0);
+
+       /* TMCS, Timer Control/Status Register
+        *
+        * 07      CMF, Compare match flag (read only) 1=match
+        * 06      ECMI, CMF Interrupt Enable: 0=disabled
+        * 05      Reserved, must be 0
+        * 04      TME, Timer Enable
+        * 03..00  Reserved, must be 0
+        *
+        * 0000 0000
+        */
+       write_reg(info, (unsigned char)(timer + TMCS), 0);
+
+       info->irq_occurred = true;
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_timer()\n",
+                       __FILE__,__LINE__,info->device_name);
+}
+
+static void isr_rxint(SLMP_INFO * info)
+{
+       struct tty_struct *tty = info->port.tty;
+       struct  mgsl_icount *icount = &info->icount;
+       unsigned char status = read_reg(info, SR1) & info->ie1_value & (FLGD + IDLD + CDCD + BRKD);
+       unsigned char status2 = read_reg(info, SR2) & info->ie2_value & OVRN;
+
+       /* clear status bits */
+       if (status)
+               write_reg(info, SR1, status);
+
+       if (status2)
+               write_reg(info, SR2, status2);
+       
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_rxint status=%02X %02x\n",
+                       __FILE__,__LINE__,info->device_name,status,status2);
+
+       if (info->params.mode == MGSL_MODE_ASYNC) {
+               if (status & BRKD) {
+                       icount->brk++;
+
+                       /* process break detection if tty control
+                        * is not set to ignore it
+                        */
+                       if (!(status & info->ignore_status_mask1)) {
+                               if (info->read_status_mask1 & BRKD) {
+                                       tty_insert_flip_char(&info->port, 0, TTY_BREAK);
+                                       if (tty && (info->port.flags & ASYNC_SAK))
+                                               do_SAK(tty);
+                               }
+                       }
+               }
+       }
+       else {
+               if (status & (FLGD|IDLD)) {
+                       if (status & FLGD)
+                               info->icount.exithunt++;
+                       else if (status & IDLD)
+                               info->icount.rxidle++;
+                       wake_up_interruptible(&info->event_wait_q);
+               }
+       }
+
+       if (status & CDCD) {
+               /* simulate a common modem status change interrupt
+                * for our handler
+                */
+               get_signals( info );
+               isr_io_pin(info,
+                       MISCSTATUS_DCD_LATCHED|(info->serial_signals&SerialSignal_DCD));
+       }
+}
+
+/*
+ * handle async rx data interrupts
+ */
+static void isr_rxrdy(SLMP_INFO * info)
+{
+       u16 status;
+       unsigned char DataByte;
+       struct  mgsl_icount *icount = &info->icount;
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_rxrdy\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       while((status = read_reg(info,CST0)) & BIT0)
+       {
+               int flag = 0;
+               bool over = false;
+               DataByte = read_reg(info,TRB);
+
+               icount->rx++;
+
+               if ( status & (PE + FRME + OVRN) ) {
+                       printk("%s(%d):%s rxerr=%04X\n",
+                               __FILE__,__LINE__,info->device_name,status);
+
+                       /* update error statistics */
+                       if (status & PE)
+                               icount->parity++;
+                       else if (status & FRME)
+                               icount->frame++;
+                       else if (status & OVRN)
+                               icount->overrun++;
+
+                       /* discard char if tty control flags say so */
+                       if (status & info->ignore_status_mask2)
+                               continue;
+
+                       status &= info->read_status_mask2;
+
+                       if (status & PE)
+                               flag = TTY_PARITY;
+                       else if (status & FRME)
+                               flag = TTY_FRAME;
+                       if (status & OVRN) {
+                               /* Overrun is special, since it's
+                                * reported immediately, and doesn't
+                                * affect the current character
+                                */
+                               over = true;
+                       }
+               }       /* end of if (error) */
+
+               tty_insert_flip_char(&info->port, DataByte, flag);
+               if (over)
+                       tty_insert_flip_char(&info->port, 0, TTY_OVERRUN);
+       }
+
+       if ( debug_level >= DEBUG_LEVEL_ISR ) {
+               printk("%s(%d):%s rx=%d brk=%d parity=%d frame=%d overrun=%d\n",
+                       __FILE__,__LINE__,info->device_name,
+                       icount->rx,icount->brk,icount->parity,
+                       icount->frame,icount->overrun);
+       }
+
+       tty_flip_buffer_push(&info->port);
+}
+
+static void isr_txeom(SLMP_INFO * info, unsigned char status)
+{
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_txeom status=%02x\n",
+                       __FILE__,__LINE__,info->device_name,status);
+
+       write_reg(info, TXDMA + DIR, 0x00); /* disable Tx DMA IRQs */
+       write_reg(info, TXDMA + DSR, 0xc0); /* clear IRQs and disable DMA */
+       write_reg(info, TXDMA + DCMD, SWABORT); /* reset/init DMA channel */
+
+       if (status & UDRN) {
+               write_reg(info, CMD, TXRESET);
+               write_reg(info, CMD, TXENABLE);
+       } else
+               write_reg(info, CMD, TXBUFCLR);
+
+       /* disable and clear tx interrupts */
+       info->ie0_value &= ~TXRDYE;
+       info->ie1_value &= ~(IDLE + UDRN);
+       write_reg16(info, IE0, (unsigned short)((info->ie1_value << 8) + info->ie0_value));
+       write_reg(info, SR1, (unsigned char)(UDRN + IDLE));
+
+       if ( info->tx_active ) {
+               if (info->params.mode != MGSL_MODE_ASYNC) {
+                       if (status & UDRN)
+                               info->icount.txunder++;
+                       else if (status & IDLE)
+                               info->icount.txok++;
+               }
+
+               info->tx_active = false;
+               info->tx_count = info->tx_put = info->tx_get = 0;
+
+               del_timer(&info->tx_timer);
+
+               if (info->params.mode != MGSL_MODE_ASYNC && info->drop_rts_on_tx_done ) {
+                       info->serial_signals &= ~SerialSignal_RTS;
+                       info->drop_rts_on_tx_done = false;
+                       set_signals(info);
+               }
+
+#if SYNCLINK_GENERIC_HDLC
+               if (info->netcount)
+                       hdlcdev_tx_done(info);
+               else
+#endif
+               {
+                       if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
+                               tx_stop(info);
+                               return;
+                       }
+                       info->pending_bh |= BH_TRANSMIT;
+               }
+       }
+}
+
+
+/*
+ * handle tx status interrupts
+ */
+static void isr_txint(SLMP_INFO * info)
+{
+       unsigned char status = read_reg(info, SR1) & info->ie1_value & (UDRN + IDLE + CCTS);
+
+       /* clear status bits */
+       write_reg(info, SR1, status);
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_txint status=%02x\n",
+                       __FILE__,__LINE__,info->device_name,status);
+
+       if (status & (UDRN + IDLE))
+               isr_txeom(info, status);
+
+       if (status & CCTS) {
+               /* simulate a common modem status change interrupt
+                * for our handler
+                */
+               get_signals( info );
+               isr_io_pin(info,
+                       MISCSTATUS_CTS_LATCHED|(info->serial_signals&SerialSignal_CTS));
+
+       }
+}
+
+/*
+ * handle async tx data interrupts
+ */
+static void isr_txrdy(SLMP_INFO * info)
+{
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_txrdy() tx_count=%d\n",
+                       __FILE__,__LINE__,info->device_name,info->tx_count);
+
+       if (info->params.mode != MGSL_MODE_ASYNC) {
+               /* disable TXRDY IRQ, enable IDLE IRQ */
+               info->ie0_value &= ~TXRDYE;
+               info->ie1_value |= IDLE;
+               write_reg16(info, IE0, (unsigned short)((info->ie1_value << 8) + info->ie0_value));
+               return;
+       }
+
+       if (info->port.tty && (info->port.tty->stopped || info->port.tty->hw_stopped)) {
+               tx_stop(info);
+               return;
+       }
+
+       if ( info->tx_count )
+               tx_load_fifo( info );
+       else {
+               info->tx_active = false;
+               info->ie0_value &= ~TXRDYE;
+               write_reg(info, IE0, info->ie0_value);
+       }
+
+       if (info->tx_count < WAKEUP_CHARS)
+               info->pending_bh |= BH_TRANSMIT;
+}
+
+static void isr_rxdmaok(SLMP_INFO * info)
+{
+       /* BIT7 = EOT (end of transfer)
+        * BIT6 = EOM (end of message/frame)
+        */
+       unsigned char status = read_reg(info,RXDMA + DSR) & 0xc0;
+
+       /* clear IRQ (BIT0 must be 1 to prevent clearing DE bit) */
+       write_reg(info, RXDMA + DSR, (unsigned char)(status | 1));
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_rxdmaok(), status=%02x\n",
+                       __FILE__,__LINE__,info->device_name,status);
+
+       info->pending_bh |= BH_RECEIVE;
+}
+
+static void isr_rxdmaerror(SLMP_INFO * info)
+{
+       /* BIT5 = BOF (buffer overflow)
+        * BIT4 = COF (counter overflow)
+        */
+       unsigned char status = read_reg(info,RXDMA + DSR) & 0x30;
+
+       /* clear IRQ (BIT0 must be 1 to prevent clearing DE bit) */
+       write_reg(info, RXDMA + DSR, (unsigned char)(status | 1));
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_rxdmaerror(), status=%02x\n",
+                       __FILE__,__LINE__,info->device_name,status);
+
+       info->rx_overflow = true;
+       info->pending_bh |= BH_RECEIVE;
+}
+
+static void isr_txdmaok(SLMP_INFO * info)
+{
+       unsigned char status_reg1 = read_reg(info, SR1);
+
+       write_reg(info, TXDMA + DIR, 0x00);     /* disable Tx DMA IRQs */
+       write_reg(info, TXDMA + DSR, 0xc0); /* clear IRQs and disable DMA */
+       write_reg(info, TXDMA + DCMD, SWABORT); /* reset/init DMA channel */
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_txdmaok(), status=%02x\n",
+                       __FILE__,__LINE__,info->device_name,status_reg1);
+
+       /* program TXRDY as FIFO empty flag, enable TXRDY IRQ */
+       write_reg16(info, TRC0, 0);
+       info->ie0_value |= TXRDYE;
+       write_reg(info, IE0, info->ie0_value);
+}
+
+static void isr_txdmaerror(SLMP_INFO * info)
+{
+       /* BIT5 = BOF (buffer overflow)
+        * BIT4 = COF (counter overflow)
+        */
+       unsigned char status = read_reg(info,TXDMA + DSR) & 0x30;
+
+       /* clear IRQ (BIT0 must be 1 to prevent clearing DE bit) */
+       write_reg(info, TXDMA + DSR, (unsigned char)(status | 1));
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):%s isr_txdmaerror(), status=%02x\n",
+                       __FILE__,__LINE__,info->device_name,status);
+}
+
+/* handle input serial signal changes
+ */
+static void isr_io_pin( SLMP_INFO *info, u16 status )
+{
+       struct  mgsl_icount *icount;
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk("%s(%d):isr_io_pin status=%04X\n",
+                       __FILE__,__LINE__,status);
+
+       if (status & (MISCSTATUS_CTS_LATCHED | MISCSTATUS_DCD_LATCHED |
+                     MISCSTATUS_DSR_LATCHED | MISCSTATUS_RI_LATCHED) ) {
+               icount = &info->icount;
+               /* update input line counters */
+               if (status & MISCSTATUS_RI_LATCHED) {
+                       icount->rng++;
+                       if ( status & SerialSignal_RI )
+                               info->input_signal_events.ri_up++;
+                       else
+                               info->input_signal_events.ri_down++;
+               }
+               if (status & MISCSTATUS_DSR_LATCHED) {
+                       icount->dsr++;
+                       if ( status & SerialSignal_DSR )
+                               info->input_signal_events.dsr_up++;
+                       else
+                               info->input_signal_events.dsr_down++;
+               }
+               if (status & MISCSTATUS_DCD_LATCHED) {
+                       if ((info->dcd_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT) {
+                               info->ie1_value &= ~CDCD;
+                               write_reg(info, IE1, info->ie1_value);
+                       }
+                       icount->dcd++;
+                       if (status & SerialSignal_DCD) {
+                               info->input_signal_events.dcd_up++;
+                       } else
+                               info->input_signal_events.dcd_down++;
+#if SYNCLINK_GENERIC_HDLC
+                       if (info->netcount) {
+                               if (status & SerialSignal_DCD)
+                                       netif_carrier_on(info->netdev);
+                               else
+                                       netif_carrier_off(info->netdev);
+                       }
+#endif
+               }
+               if (status & MISCSTATUS_CTS_LATCHED)
+               {
+                       if ((info->cts_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT) {
+                               info->ie1_value &= ~CCTS;
+                               write_reg(info, IE1, info->ie1_value);
+                       }
+                       icount->cts++;
+                       if ( status & SerialSignal_CTS )
+                               info->input_signal_events.cts_up++;
+                       else
+                               info->input_signal_events.cts_down++;
+               }
+               wake_up_interruptible(&info->status_event_wait_q);
+               wake_up_interruptible(&info->event_wait_q);
+
+               if ( (info->port.flags & ASYNC_CHECK_CD) &&
+                    (status & MISCSTATUS_DCD_LATCHED) ) {
+                       if ( debug_level >= DEBUG_LEVEL_ISR )
+                               printk("%s CD now %s...", info->device_name,
+                                      (status & SerialSignal_DCD) ? "on" : "off");
+                       if (status & SerialSignal_DCD)
+                               wake_up_interruptible(&info->port.open_wait);
+                       else {
+                               if ( debug_level >= DEBUG_LEVEL_ISR )
+                                       printk("doing serial hangup...");
+                               if (info->port.tty)
+                                       tty_hangup(info->port.tty);
+                       }
+               }
+
+               if (tty_port_cts_enabled(&info->port) &&
+                    (status & MISCSTATUS_CTS_LATCHED) ) {
+                       if ( info->port.tty ) {
+                               if (info->port.tty->hw_stopped) {
+                                       if (status & SerialSignal_CTS) {
+                                               if ( debug_level >= DEBUG_LEVEL_ISR )
+                                                       printk("CTS tx start...");
+                                               info->port.tty->hw_stopped = 0;
+                                               tx_start(info);
+                                               info->pending_bh |= BH_TRANSMIT;
+                                               return;
+                                       }
+                               } else {
+                                       if (!(status & SerialSignal_CTS)) {
+                                               if ( debug_level >= DEBUG_LEVEL_ISR )
+                                                       printk("CTS tx stop...");
+                                               info->port.tty->hw_stopped = 1;
+                                               tx_stop(info);
+                                       }
+                               }
+                       }
+               }
+       }
+
+       info->pending_bh |= BH_STATUS;
+}
+
+/* Interrupt service routine entry point.
+ *
+ * Arguments:
+ *     irq             interrupt number that caused interrupt
+ *     dev_id          device ID supplied during interrupt registration
+ *     regs            interrupted processor context
+ */
+static irqreturn_t synclinkmp_interrupt(int dummy, void *dev_id)
+{
+       SLMP_INFO *info = dev_id;
+       unsigned char status, status0, status1=0;
+       unsigned char dmastatus, dmastatus0, dmastatus1=0;
+       unsigned char timerstatus0, timerstatus1=0;
+       unsigned char shift;
+       unsigned int i;
+       unsigned short tmp;
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk(KERN_DEBUG "%s(%d): synclinkmp_interrupt(%d)entry.\n",
+                       __FILE__, __LINE__, info->irq_level);
+
+       spin_lock(&info->lock);
+
+       for(;;) {
+
+               /* get status for SCA0 (ports 0-1) */
+               tmp = read_reg16(info, ISR0);   /* get ISR0 and ISR1 in one read */
+               status0 = (unsigned char)tmp;
+               dmastatus0 = (unsigned char)(tmp>>8);
+               timerstatus0 = read_reg(info, ISR2);
+
+               if ( debug_level >= DEBUG_LEVEL_ISR )
+                       printk(KERN_DEBUG "%s(%d):%s status0=%02x, dmastatus0=%02x, timerstatus0=%02x\n",
+                               __FILE__, __LINE__, info->device_name,
+                               status0, dmastatus0, timerstatus0);
+
+               if (info->port_count == 4) {
+                       /* get status for SCA1 (ports 2-3) */
+                       tmp = read_reg16(info->port_array[2], ISR0);
+                       status1 = (unsigned char)tmp;
+                       dmastatus1 = (unsigned char)(tmp>>8);
+                       timerstatus1 = read_reg(info->port_array[2], ISR2);
+
+                       if ( debug_level >= DEBUG_LEVEL_ISR )
+                               printk("%s(%d):%s status1=%02x, dmastatus1=%02x, timerstatus1=%02x\n",
+                                       __FILE__,__LINE__,info->device_name,
+                                       status1,dmastatus1,timerstatus1);
+               }
+
+               if (!status0 && !dmastatus0 && !timerstatus0 &&
+                        !status1 && !dmastatus1 && !timerstatus1)
+                       break;
+
+               for(i=0; i < info->port_count ; i++) {
+                       if (info->port_array[i] == NULL)
+                               continue;
+                       if (i < 2) {
+                               status = status0;
+                               dmastatus = dmastatus0;
+                       } else {
+                               status = status1;
+                               dmastatus = dmastatus1;
+                       }
+
+                       shift = i & 1 ? 4 :0;
+
+                       if (status & BIT0 << shift)
+                               isr_rxrdy(info->port_array[i]);
+                       if (status & BIT1 << shift)
+                               isr_txrdy(info->port_array[i]);
+                       if (status & BIT2 << shift)
+                               isr_rxint(info->port_array[i]);
+                       if (status & BIT3 << shift)
+                               isr_txint(info->port_array[i]);
+
+                       if (dmastatus & BIT0 << shift)
+                               isr_rxdmaerror(info->port_array[i]);
+                       if (dmastatus & BIT1 << shift)
+                               isr_rxdmaok(info->port_array[i]);
+                       if (dmastatus & BIT2 << shift)
+                               isr_txdmaerror(info->port_array[i]);
+                       if (dmastatus & BIT3 << shift)
+                               isr_txdmaok(info->port_array[i]);
+               }
+
+               if (timerstatus0 & (BIT5 | BIT4))
+                       isr_timer(info->port_array[0]);
+               if (timerstatus0 & (BIT7 | BIT6))
+                       isr_timer(info->port_array[1]);
+               if (timerstatus1 & (BIT5 | BIT4))
+                       isr_timer(info->port_array[2]);
+               if (timerstatus1 & (BIT7 | BIT6))
+                       isr_timer(info->port_array[3]);
+       }
+
+       for(i=0; i < info->port_count ; i++) {
+               SLMP_INFO * port = info->port_array[i];
+
+               /* Request bottom half processing if there's something
+                * for it to do and the bh is not already running.
+                *
+                * Note: startup adapter diags require interrupts.
+                * do not request bottom half processing if the
+                * device is not open in a normal mode.
+                */
+               if ( port && (port->port.count || port->netcount) &&
+                    port->pending_bh && !port->bh_running &&
+                    !port->bh_requested ) {
+                       if ( debug_level >= DEBUG_LEVEL_ISR )
+                               printk("%s(%d):%s queueing bh task.\n",
+                                       __FILE__,__LINE__,port->device_name);
+                       schedule_work(&port->task);
+                       port->bh_requested = true;
+               }
+       }
+
+       spin_unlock(&info->lock);
+
+       if ( debug_level >= DEBUG_LEVEL_ISR )
+               printk(KERN_DEBUG "%s(%d):synclinkmp_interrupt(%d)exit.\n",
+                       __FILE__, __LINE__, info->irq_level);
+       return IRQ_HANDLED;
+}
+
+/* Initialize and start device.
+ */
+static int startup(SLMP_INFO * info)
+{
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk("%s(%d):%s tx_releaseup()\n",__FILE__,__LINE__,info->device_name);
+
+       if (info->port.flags & ASYNC_INITIALIZED)
+               return 0;
+
+       if (!info->tx_buf) {
+               info->tx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
+               if (!info->tx_buf) {
+                       printk(KERN_ERR"%s(%d):%s can't allocate transmit buffer\n",
+                               __FILE__,__LINE__,info->device_name);
+                       return -ENOMEM;
+               }
+       }
+
+       info->pending_bh = 0;
+
+       memset(&info->icount, 0, sizeof(info->icount));
+
+       /* program hardware for current parameters */
+       reset_port(info);
+
+       change_params(info);
+
+       mod_timer(&info->status_timer, jiffies + msecs_to_jiffies(10));
+
+       if (info->port.tty)
+               clear_bit(TTY_IO_ERROR, &info->port.tty->flags);
+
+       info->port.flags |= ASYNC_INITIALIZED;
+
+       return 0;
+}
+
+/* Called by close() and hangup() to shutdown hardware
+ */
+static void shutdown(SLMP_INFO * info)
+{
+       unsigned long flags;
+
+       if (!(info->port.flags & ASYNC_INITIALIZED))
+               return;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s synclinkmp_shutdown()\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       /* clear status wait queue because status changes */
+       /* can't happen after shutting down the hardware */
+       wake_up_interruptible(&info->status_event_wait_q);
+       wake_up_interruptible(&info->event_wait_q);
+
+       del_timer(&info->tx_timer);
+       del_timer(&info->status_timer);
+
+       kfree(info->tx_buf);
+       info->tx_buf = NULL;
+
+       spin_lock_irqsave(&info->lock,flags);
+
+       reset_port(info);
+
+       if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
+               info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+               set_signals(info);
+       }
+
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       if (info->port.tty)
+               set_bit(TTY_IO_ERROR, &info->port.tty->flags);
+
+       info->port.flags &= ~ASYNC_INITIALIZED;
+}
+
+static void program_hw(SLMP_INFO *info)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->lock,flags);
+
+       rx_stop(info);
+       tx_stop(info);
+
+       info->tx_count = info->tx_put = info->tx_get = 0;
+
+       if (info->params.mode == MGSL_MODE_HDLC || info->netcount)
+               hdlc_mode(info);
+       else
+               async_mode(info);
+
+       set_signals(info);
+
+       info->dcd_chkcount = 0;
+       info->cts_chkcount = 0;
+       info->ri_chkcount = 0;
+       info->dsr_chkcount = 0;
+
+       info->ie1_value |= (CDCD|CCTS);
+       write_reg(info, IE1, info->ie1_value);
+
+       get_signals(info);
+
+       if (info->netcount || (info->port.tty && info->port.tty->termios.c_cflag & CREAD) )
+               rx_start(info);
+
+       spin_unlock_irqrestore(&info->lock,flags);
+}
+
+/* Reconfigure adapter based on new parameters
+ */
+static void change_params(SLMP_INFO *info)
+{
+       unsigned cflag;
+       int bits_per_char;
+
+       if (!info->port.tty)
+               return;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s change_params()\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       cflag = info->port.tty->termios.c_cflag;
+
+       /* if B0 rate (hangup) specified then negate RTS and DTR */
+       /* otherwise assert RTS and DTR */
+       if (cflag & CBAUD)
+               info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
+       else
+               info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+
+       /* byte size and parity */
+
+       switch (cflag & CSIZE) {
+             case CS5: info->params.data_bits = 5; break;
+             case CS6: info->params.data_bits = 6; break;
+             case CS7: info->params.data_bits = 7; break;
+             case CS8: info->params.data_bits = 8; break;
+             /* Never happens, but GCC is too dumb to figure it out */
+             default:  info->params.data_bits = 7; break;
+             }
+
+       if (cflag & CSTOPB)
+               info->params.stop_bits = 2;
+       else
+               info->params.stop_bits = 1;
+
+       info->params.parity = ASYNC_PARITY_NONE;
+       if (cflag & PARENB) {
+               if (cflag & PARODD)
+                       info->params.parity = ASYNC_PARITY_ODD;
+               else
+                       info->params.parity = ASYNC_PARITY_EVEN;
+#ifdef CMSPAR
+               if (cflag & CMSPAR)
+                       info->params.parity = ASYNC_PARITY_SPACE;
+#endif
+       }
+
+       /* calculate number of jiffies to transmit a full
+        * FIFO (32 bytes) at specified data rate
+        */
+       bits_per_char = info->params.data_bits +
+                       info->params.stop_bits + 1;
+
+       /* if port data rate is set to 460800 or less then
+        * allow tty settings to override, otherwise keep the
+        * current data rate.
+        */
+       if (info->params.data_rate <= 460800) {
+               info->params.data_rate = tty_get_baud_rate(info->port.tty);
+       }
+
+       if ( info->params.data_rate ) {
+               info->timeout = (32*HZ*bits_per_char) /
+                               info->params.data_rate;
+       }
+       info->timeout += HZ/50;         /* Add .02 seconds of slop */
+
+       if (cflag & CRTSCTS)
+               info->port.flags |= ASYNC_CTS_FLOW;
+       else
+               info->port.flags &= ~ASYNC_CTS_FLOW;
+
+       if (cflag & CLOCAL)
+               info->port.flags &= ~ASYNC_CHECK_CD;
+       else
+               info->port.flags |= ASYNC_CHECK_CD;
+
+       /* process tty input control flags */
+
+       info->read_status_mask2 = OVRN;
+       if (I_INPCK(info->port.tty))
+               info->read_status_mask2 |= PE | FRME;
+       if (I_BRKINT(info->port.tty) || I_PARMRK(info->port.tty))
+               info->read_status_mask1 |= BRKD;
+       if (I_IGNPAR(info->port.tty))
+               info->ignore_status_mask2 |= PE | FRME;
+       if (I_IGNBRK(info->port.tty)) {
+               info->ignore_status_mask1 |= BRKD;
+               /* If ignoring parity and break indicators, ignore
+                * overruns too.  (For real raw support).
+                */
+               if (I_IGNPAR(info->port.tty))
+                       info->ignore_status_mask2 |= OVRN;
+       }
+
+       program_hw(info);
+}
+
+static int get_stats(SLMP_INFO * info, struct mgsl_icount __user *user_icount)
+{
+       int err;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s get_params()\n",
+                        __FILE__,__LINE__, info->device_name);
+
+       if (!user_icount) {
+               memset(&info->icount, 0, sizeof(info->icount));
+       } else {
+               mutex_lock(&info->port.mutex);
+               COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
+               mutex_unlock(&info->port.mutex);
+               if (err)
+                       return -EFAULT;
+       }
+
+       return 0;
+}
+
+static int get_params(SLMP_INFO * info, MGSL_PARAMS __user *user_params)
+{
+       int err;
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s get_params()\n",
+                        __FILE__,__LINE__, info->device_name);
+
+       mutex_lock(&info->port.mutex);
+       COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
+       mutex_unlock(&info->port.mutex);
+       if (err) {
+               if ( debug_level >= DEBUG_LEVEL_INFO )
+                       printk( "%s(%d):%s get_params() user buffer copy failed\n",
+                               __FILE__,__LINE__,info->device_name);
+               return -EFAULT;
+       }
+
+       return 0;
+}
+
+static int set_params(SLMP_INFO * info, MGSL_PARAMS __user *new_params)
+{
+       unsigned long flags;
+       MGSL_PARAMS tmp_params;
+       int err;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s set_params\n",
+                       __FILE__,__LINE__,info->device_name );
+       COPY_FROM_USER(err,&tmp_params, new_params, sizeof(MGSL_PARAMS));
+       if (err) {
+               if ( debug_level >= DEBUG_LEVEL_INFO )
+                       printk( "%s(%d):%s set_params() user buffer copy failed\n",
+                               __FILE__,__LINE__,info->device_name);
+               return -EFAULT;
+       }
+
+       mutex_lock(&info->port.mutex);
+       spin_lock_irqsave(&info->lock,flags);
+       memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       change_params(info);
+       mutex_unlock(&info->port.mutex);
+
+       return 0;
+}
+
+static int get_txidle(SLMP_INFO * info, int __user *idle_mode)
+{
+       int err;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s get_txidle()=%d\n",
+                        __FILE__,__LINE__, info->device_name, info->idle_mode);
+
+       COPY_TO_USER(err,idle_mode, &info->idle_mode, sizeof(int));
+       if (err) {
+               if ( debug_level >= DEBUG_LEVEL_INFO )
+                       printk( "%s(%d):%s get_txidle() user buffer copy failed\n",
+                               __FILE__,__LINE__,info->device_name);
+               return -EFAULT;
+       }
+
+       return 0;
+}
+
+static int set_txidle(SLMP_INFO * info, int idle_mode)
+{
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s set_txidle(%d)\n",
+                       __FILE__,__LINE__,info->device_name, idle_mode );
+
+       spin_lock_irqsave(&info->lock,flags);
+       info->idle_mode = idle_mode;
+       tx_set_idle( info );
+       spin_unlock_irqrestore(&info->lock,flags);
+       return 0;
+}
+
+static int tx_enable(SLMP_INFO * info, int enable)
+{
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s tx_enable(%d)\n",
+                       __FILE__,__LINE__,info->device_name, enable);
+
+       spin_lock_irqsave(&info->lock,flags);
+       if ( enable ) {
+               if ( !info->tx_enabled ) {
+                       tx_start(info);
+               }
+       } else {
+               if ( info->tx_enabled )
+                       tx_stop(info);
+       }
+       spin_unlock_irqrestore(&info->lock,flags);
+       return 0;
+}
+
+/* abort send HDLC frame
+ */
+static int tx_abort(SLMP_INFO * info)
+{
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s tx_abort()\n",
+                       __FILE__,__LINE__,info->device_name);
+
+       spin_lock_irqsave(&info->lock,flags);
+       if ( info->tx_active && info->params.mode == MGSL_MODE_HDLC ) {
+               info->ie1_value &= ~UDRN;
+               info->ie1_value |= IDLE;
+               write_reg(info, IE1, info->ie1_value);  /* disable tx status interrupts */
+               write_reg(info, SR1, (unsigned char)(IDLE + UDRN));     /* clear pending */
+
+               write_reg(info, TXDMA + DSR, 0);                /* disable DMA channel */
+               write_reg(info, TXDMA + DCMD, SWABORT); /* reset/init DMA channel */
+
+               write_reg(info, CMD, TXABORT);
+       }
+       spin_unlock_irqrestore(&info->lock,flags);
+       return 0;
+}
+
+static int rx_enable(SLMP_INFO * info, int enable)
+{
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s rx_enable(%d)\n",
+                       __FILE__,__LINE__,info->device_name,enable);
+
+       spin_lock_irqsave(&info->lock,flags);
+       if ( enable ) {
+               if ( !info->rx_enabled )
+                       rx_start(info);
+       } else {
+               if ( info->rx_enabled )
+                       rx_stop(info);
+       }
+       spin_unlock_irqrestore(&info->lock,flags);
+       return 0;
+}
+
+/* wait for specified event to occur
+ */
+static int wait_mgsl_event(SLMP_INFO * info, int __user *mask_ptr)
+{
+       unsigned long flags;
+       int s;
+       int rc=0;
+       struct mgsl_icount cprev, cnow;
+       int events;
+       int mask;
+       struct  _input_signal_events oldsigs, newsigs;
+       DECLARE_WAITQUEUE(wait, current);
+
+       COPY_FROM_USER(rc,&mask, mask_ptr, sizeof(int));
+       if (rc) {
+               return  -EFAULT;
+       }
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s wait_mgsl_event(%d)\n",
+                       __FILE__,__LINE__,info->device_name,mask);
+
+       spin_lock_irqsave(&info->lock,flags);
+
+       /* return immediately if state matches requested events */
+       get_signals(info);
+       s = info->serial_signals;
+
+       events = mask &
+               ( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
+                 ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
+                 ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
+                 ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
+       if (events) {
+               spin_unlock_irqrestore(&info->lock,flags);
+               goto exit;
+       }
+
+       /* save current irq counts */
+       cprev = info->icount;
+       oldsigs = info->input_signal_events;
+
+       /* enable hunt and idle irqs if needed */
+       if (mask & (MgslEvent_ExitHuntMode+MgslEvent_IdleReceived)) {
+               unsigned char oldval = info->ie1_value;
+               unsigned char newval = oldval +
+                        (mask & MgslEvent_ExitHuntMode ? FLGD:0) +
+                        (mask & MgslEvent_IdleReceived ? IDLD:0);
+               if ( oldval != newval ) {
+                       info->ie1_value = newval;
+                       write_reg(info, IE1, info->ie1_value);
+               }
+       }
+
+       set_current_state(TASK_INTERRUPTIBLE);
+       add_wait_queue(&info->event_wait_q, &wait);
+
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       for(;;) {
+               schedule();
+               if (signal_pending(current)) {
+                       rc = -ERESTARTSYS;
+                       break;
+               }
+
+               /* get current irq counts */
+               spin_lock_irqsave(&info->lock,flags);
+               cnow = info->icount;
+               newsigs = info->input_signal_events;
+               set_current_state(TASK_INTERRUPTIBLE);
+               spin_unlock_irqrestore(&info->lock,flags);
+
+               /* if no change, wait aborted for some reason */
+               if (newsigs.dsr_up   == oldsigs.dsr_up   &&
+                   newsigs.dsr_down == oldsigs.dsr_down &&
+                   newsigs.dcd_up   == oldsigs.dcd_up   &&
+                   newsigs.dcd_down == oldsigs.dcd_down &&
+                   newsigs.cts_up   == oldsigs.cts_up   &&
+                   newsigs.cts_down == oldsigs.cts_down &&
+                   newsigs.ri_up    == oldsigs.ri_up    &&
+                   newsigs.ri_down  == oldsigs.ri_down  &&
+                   cnow.exithunt    == cprev.exithunt   &&
+                   cnow.rxidle      == cprev.rxidle) {
+                       rc = -EIO;
+                       break;
+               }
+
+               events = mask &
+                       ( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
+                         (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
+                         (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
+                         (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
+                         (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
+                         (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
+                         (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
+                         (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
+                         (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
+                         (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
+               if (events)
+                       break;
+
+               cprev = cnow;
+               oldsigs = newsigs;
+       }
+
+       remove_wait_queue(&info->event_wait_q, &wait);
+       set_current_state(TASK_RUNNING);
+
+
+       if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
+               spin_lock_irqsave(&info->lock,flags);
+               if (!waitqueue_active(&info->event_wait_q)) {
+                       /* disable enable exit hunt mode/idle rcvd IRQs */
+                       info->ie1_value &= ~(FLGD|IDLD);
+                       write_reg(info, IE1, info->ie1_value);
+               }
+               spin_unlock_irqrestore(&info->lock,flags);
+       }
+exit:
+       if ( rc == 0 )
+               PUT_USER(rc, events, mask_ptr);
+
+       return rc;
+}
+
+static int modem_input_wait(SLMP_INFO *info,int arg)
+{
+       unsigned long flags;
+       int rc;
+       struct mgsl_icount cprev, cnow;
+       DECLARE_WAITQUEUE(wait, current);
+
+       /* save current irq counts */
+       spin_lock_irqsave(&info->lock,flags);
+       cprev = info->icount;
+       add_wait_queue(&info->status_event_wait_q, &wait);
+       set_current_state(TASK_INTERRUPTIBLE);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       for(;;) {
+               schedule();
+               if (signal_pending(current)) {
+                       rc = -ERESTARTSYS;
+                       break;
+               }
+
+               /* get new irq counts */
+               spin_lock_irqsave(&info->lock,flags);
+               cnow = info->icount;
+               set_current_state(TASK_INTERRUPTIBLE);
+               spin_unlock_irqrestore(&info->lock,flags);
+
+               /* if no change, wait aborted for some reason */
+               if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
+                   cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
+                       rc = -EIO;
+                       break;
+               }
+
+               /* check for change in caller specified modem input */
+               if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
+                   (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
+                   (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
+                   (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
+                       rc = 0;
+                       break;
+               }
+
+               cprev = cnow;
+       }
+       remove_wait_queue(&info->status_event_wait_q, &wait);
+       set_current_state(TASK_RUNNING);
+       return rc;
+}
+
+/* return the state of the serial control and status signals
+ */
+static int tiocmget(struct tty_struct *tty)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned int result;
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->lock,flags);
+       get_signals(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS : 0) |
+                ((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR : 0) |
+                ((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR : 0) |
+                ((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG : 0) |
+                ((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR : 0) |
+                ((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS : 0);
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s tiocmget() value=%08X\n",
+                        __FILE__,__LINE__, info->device_name, result );
+       return result;
+}
+
+/* set modem control signals (DTR/RTS)
+ */
+static int tiocmset(struct tty_struct *tty,
+                                       unsigned int set, unsigned int clear)
+{
+       SLMP_INFO *info = tty->driver_data;
+       unsigned long flags;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s tiocmset(%x,%x)\n",
+                       __FILE__,__LINE__,info->device_name, set, clear);
+
+       if (set & TIOCM_RTS)
+               info->serial_signals |= SerialSignal_RTS;
+       if (set & TIOCM_DTR)
+               info->serial_signals |= SerialSignal_DTR;
+       if (clear & TIOCM_RTS)
+               info->serial_signals &= ~SerialSignal_RTS;
+       if (clear & TIOCM_DTR)
+               info->serial_signals &= ~SerialSignal_DTR;
+
+       spin_lock_irqsave(&info->lock,flags);
+       set_signals(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       return 0;
+}
+
+static int carrier_raised(struct tty_port *port)
+{
+       SLMP_INFO *info = container_of(port, SLMP_INFO, port);
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->lock,flags);
+       get_signals(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       return (info->serial_signals & SerialSignal_DCD) ? 1 : 0;
+}
+
+static void dtr_rts(struct tty_port *port, int on)
+{
+       SLMP_INFO *info = container_of(port, SLMP_INFO, port);
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->lock,flags);
+       if (on)
+               info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
+       else
+               info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+       set_signals(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+}
+
+/* Block the current process until the specified port is ready to open.
+ */
+static int block_til_ready(struct tty_struct *tty, struct file *filp,
+                          SLMP_INFO *info)
+{
+       DECLARE_WAITQUEUE(wait, current);
+       int             retval;
+       bool            do_clocal = false;
+       unsigned long   flags;
+       int             cd;
+       struct tty_port *port = &info->port;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s block_til_ready()\n",
+                        __FILE__,__LINE__, tty->driver->name );
+
+       if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
+               /* nonblock mode is set or port is not enabled */
+               /* just verify that callout device is not active */
+               port->flags |= ASYNC_NORMAL_ACTIVE;
+               return 0;
+       }
+
+       if (tty->termios.c_cflag & CLOCAL)
+               do_clocal = true;
+
+       /* Wait for carrier detect and the line to become
+        * free (i.e., not in use by the callout).  While we are in
+        * this loop, port->count is dropped by one, so that
+        * close() knows when to free things.  We restore it upon
+        * exit, either normal or abnormal.
+        */
+
+       retval = 0;
+       add_wait_queue(&port->open_wait, &wait);
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s block_til_ready() before block, count=%d\n",
+                        __FILE__,__LINE__, tty->driver->name, port->count );
+
+       spin_lock_irqsave(&info->lock, flags);
+       port->count--;
+       spin_unlock_irqrestore(&info->lock, flags);
+       port->blocked_open++;
+
+       while (1) {
+               if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
+                       tty_port_raise_dtr_rts(port);
+
+               set_current_state(TASK_INTERRUPTIBLE);
+
+               if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)){
+                       retval = (port->flags & ASYNC_HUP_NOTIFY) ?
+                                       -EAGAIN : -ERESTARTSYS;
+                       break;
+               }
+
+               cd = tty_port_carrier_raised(port);
+
+               if (!(port->flags & ASYNC_CLOSING) && (do_clocal || cd))
+                       break;
+
+               if (signal_pending(current)) {
+                       retval = -ERESTARTSYS;
+                       break;
+               }
+
+               if (debug_level >= DEBUG_LEVEL_INFO)
+                       printk("%s(%d):%s block_til_ready() count=%d\n",
+                                __FILE__,__LINE__, tty->driver->name, port->count );
+
+               tty_unlock(tty);
+               schedule();
+               tty_lock(tty);
+       }
+
+       set_current_state(TASK_RUNNING);
+       remove_wait_queue(&port->open_wait, &wait);
+       if (!tty_hung_up_p(filp))
+               port->count++;
+       port->blocked_open--;
+
+       if (debug_level >= DEBUG_LEVEL_INFO)
+               printk("%s(%d):%s block_til_ready() after, count=%d\n",
+                        __FILE__,__LINE__, tty->driver->name, port->count );
+
+       if (!retval)
+               port->flags |= ASYNC_NORMAL_ACTIVE;
+
+       return retval;
+}
+
+static int alloc_dma_bufs(SLMP_INFO *info)
+{
+       unsigned short BuffersPerFrame;
+       unsigned short BufferCount;
+
+       // Force allocation to start at 64K boundary for each port.
+       // This is necessary because *all* buffer descriptors for a port
+       // *must* be in the same 64K block. All descriptors on a port
+       // share a common 'base' address (upper 8 bits of 24 bits) programmed
+       // into the CBP register.
+       info->port_array[0]->last_mem_alloc = (SCA_MEM_SIZE/4) * info->port_num;
+
+       /* Calculate the number of DMA buffers necessary to hold the */
+       /* largest allowable frame size. Note: If the max frame size is */
+       /* not an even multiple of the DMA buffer size then we need to */
+       /* round the buffer count per frame up one. */
+
+       BuffersPerFrame = (unsigned short)(info->max_frame_size/SCABUFSIZE);
+       if ( info->max_frame_size % SCABUFSIZE )
+               BuffersPerFrame++;
+
+       /* calculate total number of data buffers (SCABUFSIZE) possible
+        * in one ports memory (SCA_MEM_SIZE/4) after allocating memory
+        * for the descriptor list (BUFFERLISTSIZE).
+        */
+       BufferCount = (SCA_MEM_SIZE/4 - BUFFERLISTSIZE)/SCABUFSIZE;
+
+       /* limit number of buffers to maximum amount of descriptors */
+       if (BufferCount > BUFFERLISTSIZE/sizeof(SCADESC))
+               BufferCount = BUFFERLISTSIZE/sizeof(SCADESC);
+
+       /* use enough buffers to transmit one max size frame */
+       info->tx_buf_count = BuffersPerFrame + 1;
+
+       /* never use more than half the available buffers for transmit */
+       if (info->tx_buf_count > (BufferCount/2))
+               info->tx_buf_count = BufferCount/2;
+
+       if (info->tx_buf_count > SCAMAXDESC)
+               info->tx_buf_count = SCAMAXDESC;
+
+       /* use remaining buffers for receive */
+       info->rx_buf_count = BufferCount - info->tx_buf_count;
+
+       if (info->rx_buf_count > SCAMAXDESC)
+               info->rx_buf_count = SCAMAXDESC;
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk("%s(%d):%s Allocating %d TX and %d RX DMA buffers.\n",
+                       __FILE__,__LINE__, info->device_name,
+                       info->tx_buf_count,info->rx_buf_count);
+
+       if ( alloc_buf_list( info ) < 0 ||
+               alloc_frame_bufs(info,
+                                       info->rx_buf_list,
+                                       info->rx_buf_list_ex,
+                                       info->rx_buf_count) < 0 ||
+               alloc_frame_bufs(info,
+                                       info->tx_buf_list,
+                                       info->tx_buf_list_ex,
+                                       info->tx_buf_count) < 0 ||
+               alloc_tmp_rx_buf(info) < 0 ) {
+               printk("%s(%d):%s Can't allocate DMA buffer memory\n",
+                       __FILE__,__LINE__, info->device_name);
+               return -ENOMEM;
+       }
+
+       rx_reset_buffers( info );
+
+       return 0;
+}
+
+/* Allocate DMA buffers for the transmit and receive descriptor lists.
+ */
+static int alloc_buf_list(SLMP_INFO *info)
+{
+       unsigned int i;
+
+       /* build list in adapter shared memory */
+       info->buffer_list = info->memory_base + info->port_array[0]->last_mem_alloc;
+       info->buffer_list_phys = info->port_array[0]->last_mem_alloc;
+       info->port_array[0]->last_mem_alloc += BUFFERLISTSIZE;
+
+       memset(info->buffer_list, 0, BUFFERLISTSIZE);
+
+       /* Save virtual address pointers to the receive and */
+       /* transmit buffer lists. (Receive 1st). These pointers will */
+       /* be used by the processor to access the lists. */
+       info->rx_buf_list = (SCADESC *)info->buffer_list;
+
+       info->tx_buf_list = (SCADESC *)info->buffer_list;
+       info->tx_buf_list += info->rx_buf_count;
+
+       /* Build links for circular buffer entry lists (tx and rx)
+        *
+        * Note: links are physical addresses read by the SCA device
+        * to determine the next buffer entry to use.
+        */
+
+       for ( i = 0; i < info->rx_buf_count; i++ ) {
+               /* calculate and store physical address of this buffer entry */
+               info->rx_buf_list_ex[i].phys_entry =
+                       info->buffer_list_phys + (i * SCABUFSIZE);
+
+               /* calculate and store physical address of */
+               /* next entry in cirular list of entries */
+               info->rx_buf_list[i].next = info->buffer_list_phys;
+               if ( i < info->rx_buf_count - 1 )
+                       info->rx_buf_list[i].next += (i + 1) * sizeof(SCADESC);
+
+               info->rx_buf_list[i].length = SCABUFSIZE;
+       }
+
+       for ( i = 0; i < info->tx_buf_count; i++ ) {
+               /* calculate and store physical address of this buffer entry */
+               info->tx_buf_list_ex[i].phys_entry = info->buffer_list_phys +
+                       ((info->rx_buf_count + i) * sizeof(SCADESC));
+
+               /* calculate and store physical address of */
+               /* next entry in cirular list of entries */
+
+               info->tx_buf_list[i].next = info->buffer_list_phys +
+                       info->rx_buf_count * sizeof(SCADESC);
+
+               if ( i < info->tx_buf_count - 1 )
+                       info->tx_buf_list[i].next += (i + 1) * sizeof(SCADESC);
+       }
+
+       return 0;
+}
+
+/* Allocate the frame DMA buffers used by the specified buffer list.
+ */
+static int alloc_frame_bufs(SLMP_INFO *info, SCADESC *buf_list,SCADESC_EX *buf_list_ex,int count)
+{
+       int i;
+       unsigned long phys_addr;
+
+       for ( i = 0; i < count; i++ ) {
+               buf_list_ex[i].virt_addr = info->memory_base + info->port_array[0]->last_mem_alloc;
+               phys_addr = info->port_array[0]->last_mem_alloc;
+               info->port_array[0]->last_mem_alloc += SCABUFSIZE;
+
+               buf_list[i].buf_ptr  = (unsigned short)phys_addr;
+               buf_list[i].buf_base = (unsigned char)(phys_addr >> 16);
+       }
+
+       return 0;
+}
+
+static void free_dma_bufs(SLMP_INFO *info)
+{
+       info->buffer_list = NULL;
+       info->rx_buf_list = NULL;
+       info->tx_buf_list = NULL;
+}
+
+/* allocate buffer large enough to hold max_frame_size.
+ * This buffer is used to pass an assembled frame to the line discipline.
+ */
+static int alloc_tmp_rx_buf(SLMP_INFO *info)
+{
+       info->tmp_rx_buf = kmalloc(info->max_frame_size, GFP_KERNEL);
+       if (info->tmp_rx_buf == NULL)
+               return -ENOMEM;
+       /* unused flag buffer to satisfy receive_buf calling interface */
+       info->flag_buf = kzalloc(info->max_frame_size, GFP_KERNEL);
+       if (!info->flag_buf) {
+               kfree(info->tmp_rx_buf);
+               info->tmp_rx_buf = NULL;
+               return -ENOMEM;
+       }
+       return 0;
+}
+
+static void free_tmp_rx_buf(SLMP_INFO *info)
+{
+       kfree(info->tmp_rx_buf);
+       info->tmp_rx_buf = NULL;
+       kfree(info->flag_buf);
+       info->flag_buf = NULL;
+}
+
+static int claim_resources(SLMP_INFO *info)
+{
+       if (request_mem_region(info->phys_memory_base,SCA_MEM_SIZE,"synclinkmp") == NULL) {
+               printk( "%s(%d):%s mem addr conflict, Addr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_memory_base);
+               info->init_error = DiagStatus_AddressConflict;
+               goto errout;
+       }
+       else
+               info->shared_mem_requested = true;
+
+       if (request_mem_region(info->phys_lcr_base + info->lcr_offset,128,"synclinkmp") == NULL) {
+               printk( "%s(%d):%s lcr mem addr conflict, Addr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_lcr_base);
+               info->init_error = DiagStatus_AddressConflict;
+               goto errout;
+       }
+       else
+               info->lcr_mem_requested = true;
+
+       if (request_mem_region(info->phys_sca_base + info->sca_offset,SCA_BASE_SIZE,"synclinkmp") == NULL) {
+               printk( "%s(%d):%s sca mem addr conflict, Addr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_sca_base);
+               info->init_error = DiagStatus_AddressConflict;
+               goto errout;
+       }
+       else
+               info->sca_base_requested = true;
+
+       if (request_mem_region(info->phys_statctrl_base + info->statctrl_offset,SCA_REG_SIZE,"synclinkmp") == NULL) {
+               printk( "%s(%d):%s stat/ctrl mem addr conflict, Addr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_statctrl_base);
+               info->init_error = DiagStatus_AddressConflict;
+               goto errout;
+       }
+       else
+               info->sca_statctrl_requested = true;
+
+       info->memory_base = ioremap_nocache(info->phys_memory_base,
+                                                               SCA_MEM_SIZE);
+       if (!info->memory_base) {
+               printk( "%s(%d):%s Can't map shared memory, MemAddr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_memory_base );
+               info->init_error = DiagStatus_CantAssignPciResources;
+               goto errout;
+       }
+
+       info->lcr_base = ioremap_nocache(info->phys_lcr_base, PAGE_SIZE);
+       if (!info->lcr_base) {
+               printk( "%s(%d):%s Can't map LCR memory, MemAddr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_lcr_base );
+               info->init_error = DiagStatus_CantAssignPciResources;
+               goto errout;
+       }
+       info->lcr_base += info->lcr_offset;
+
+       info->sca_base = ioremap_nocache(info->phys_sca_base, PAGE_SIZE);
+       if (!info->sca_base) {
+               printk( "%s(%d):%s Can't map SCA memory, MemAddr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_sca_base );
+               info->init_error = DiagStatus_CantAssignPciResources;
+               goto errout;
+       }
+       info->sca_base += info->sca_offset;
+
+       info->statctrl_base = ioremap_nocache(info->phys_statctrl_base,
+                                                               PAGE_SIZE);
+       if (!info->statctrl_base) {
+               printk( "%s(%d):%s Can't map SCA Status/Control memory, MemAddr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_statctrl_base );
+               info->init_error = DiagStatus_CantAssignPciResources;
+               goto errout;
+       }
+       info->statctrl_base += info->statctrl_offset;
+
+       if ( !memory_test(info) ) {
+               printk( "%s(%d):Shared Memory Test failed for device %s MemAddr=%08X\n",
+                       __FILE__,__LINE__,info->device_name, info->phys_memory_base );
+               info->init_error = DiagStatus_MemoryError;
+               goto errout;
+       }
+
+       return 0;
+
+errout:
+       release_resources( info );
+       return -ENODEV;
+}
+
+static void release_resources(SLMP_INFO *info)
+{
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk( "%s(%d):%s release_resources() entry\n",
+                       __FILE__,__LINE__,info->device_name );
+
+       if ( info->irq_requested ) {
+               free_irq(info->irq_level, info);
+               info->irq_requested = false;
+       }
+
+       if ( info->shared_mem_requested ) {
+               release_mem_region(info->phys_memory_base,SCA_MEM_SIZE);
+               info->shared_mem_requested = false;
+       }
+       if ( info->lcr_mem_requested ) {
+               release_mem_region(info->phys_lcr_base + info->lcr_offset,128);
+               info->lcr_mem_requested = false;
+       }
+       if ( info->sca_base_requested ) {
+               release_mem_region(info->phys_sca_base + info->sca_offset,SCA_BASE_SIZE);
+               info->sca_base_requested = false;
+       }
+       if ( info->sca_statctrl_requested ) {
+               release_mem_region(info->phys_statctrl_base + info->statctrl_offset,SCA_REG_SIZE);
+               info->sca_statctrl_requested = false;
+       }
+
+       if (info->memory_base){
+               iounmap(info->memory_base);
+               info->memory_base = NULL;
+       }
+
+       if (info->sca_base) {
+               iounmap(info->sca_base - info->sca_offset);
+               info->sca_base=NULL;
+       }
+
+       if (info->statctrl_base) {
+               iounmap(info->statctrl_base - info->statctrl_offset);
+               info->statctrl_base=NULL;
+       }
+
+       if (info->lcr_base){
+               iounmap(info->lcr_base - info->lcr_offset);
+               info->lcr_base = NULL;
+       }
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk( "%s(%d):%s release_resources() exit\n",
+                       __FILE__,__LINE__,info->device_name );
+}
+
+/* Add the specified device instance data structure to the
+ * global linked list of devices and increment the device count.
+ */
+static void add_device(SLMP_INFO *info)
+{
+       info->next_device = NULL;
+       info->line = synclinkmp_device_count;
+       sprintf(info->device_name,"ttySLM%dp%d",info->adapter_num,info->port_num);
+
+       if (info->line < MAX_DEVICES) {
+               if (maxframe[info->line])
+                       info->max_frame_size = maxframe[info->line];
+       }
+
+       synclinkmp_device_count++;
+
+       if ( !synclinkmp_device_list )
+               synclinkmp_device_list = info;
+       else {
+               SLMP_INFO *current_dev = synclinkmp_device_list;
+               while( current_dev->next_device )
+                       current_dev = current_dev->next_device;
+               current_dev->next_device = info;
+       }
+
+       if ( info->max_frame_size < 4096 )
+               info->max_frame_size = 4096;
+       else if ( info->max_frame_size > 65535 )
+               info->max_frame_size = 65535;
+
+       printk( "SyncLink MultiPort %s: "
+               "Mem=(%08x %08X %08x %08X) IRQ=%d MaxFrameSize=%u\n",
+               info->device_name,
+               info->phys_sca_base,
+               info->phys_memory_base,
+               info->phys_statctrl_base,
+               info->phys_lcr_base,
+               info->irq_level,
+               info->max_frame_size );
+
+#if SYNCLINK_GENERIC_HDLC
+       hdlcdev_init(info);
+#endif
+}
+
+static const struct tty_port_operations port_ops = {
+       .carrier_raised = carrier_raised,
+       .dtr_rts = dtr_rts,
+};
+
+/* Allocate and initialize a device instance structure
+ *
+ * Return Value:       pointer to SLMP_INFO if success, otherwise NULL
+ */
+static SLMP_INFO *alloc_dev(int adapter_num, int port_num, struct pci_dev *pdev)
+{
+       SLMP_INFO *info;
+
+       info = kzalloc(sizeof(SLMP_INFO),
+                GFP_KERNEL);
+
+       if (!info) {
+               printk("%s(%d) Error can't allocate device instance data for adapter %d, port %d\n",
+                       __FILE__,__LINE__, adapter_num, port_num);
+       } else {
+               tty_port_init(&info->port);
+               info->port.ops = &port_ops;
+               info->magic = MGSL_MAGIC;
+               INIT_WORK(&info->task, bh_handler);
+               info->max_frame_size = 4096;
+               info->port.close_delay = 5*HZ/10;
+               info->port.closing_wait = 30*HZ;
+               init_waitqueue_head(&info->status_event_wait_q);
+               init_waitqueue_head(&info->event_wait_q);
+               spin_lock_init(&info->netlock);
+               memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
+               info->idle_mode = HDLC_TXIDLE_FLAGS;
+               info->adapter_num = adapter_num;
+               info->port_num = port_num;
+
+               /* Copy configuration info to device instance data */
+               info->irq_level = pdev->irq;
+               info->phys_lcr_base = pci_resource_start(pdev,0);
+               info->phys_sca_base = pci_resource_start(pdev,2);
+               info->phys_memory_base = pci_resource_start(pdev,3);
+               info->phys_statctrl_base = pci_resource_start(pdev,4);
+
+               /* Because veremap only works on page boundaries we must map
+                * a larger area than is actually implemented for the LCR
+                * memory range. We map a full page starting at the page boundary.
+                */
+               info->lcr_offset    = info->phys_lcr_base & (PAGE_SIZE-1);
+               info->phys_lcr_base &= ~(PAGE_SIZE-1);
+
+               info->sca_offset    = info->phys_sca_base & (PAGE_SIZE-1);
+               info->phys_sca_base &= ~(PAGE_SIZE-1);
+
+               info->statctrl_offset    = info->phys_statctrl_base & (PAGE_SIZE-1);
+               info->phys_statctrl_base &= ~(PAGE_SIZE-1);
+
+               info->bus_type = MGSL_BUS_TYPE_PCI;
+               info->irq_flags = IRQF_SHARED;
+
+               setup_timer(&info->tx_timer, tx_timeout, (unsigned long)info);
+               setup_timer(&info->status_timer, status_timeout,
+                               (unsigned long)info);
+
+               /* Store the PCI9050 misc control register value because a flaw
+                * in the PCI9050 prevents LCR registers from being read if
+                * BIOS assigns an LCR base address with bit 7 set.
+                *
+                * Only the misc control register is accessed for which only
+                * write access is needed, so set an initial value and change
+                * bits to the device instance data as we write the value
+                * to the actual misc control register.
+                */
+               info->misc_ctrl_value = 0x087e4546;
+
+               /* initial port state is unknown - if startup errors
+                * occur, init_error will be set to indicate the
+                * problem. Once the port is fully initialized,
+                * this value will be set to 0 to indicate the
+                * port is available.
+                */
+               info->init_error = -1;
+       }
+
+       return info;
+}
+
+static void device_init(int adapter_num, struct pci_dev *pdev)
+{
+       SLMP_INFO *port_array[SCA_MAX_PORTS];
+       int port;
+
+       /* allocate device instances for up to SCA_MAX_PORTS devices */
+       for ( port = 0; port < SCA_MAX_PORTS; ++port ) {
+               port_array[port] = alloc_dev(adapter_num,port,pdev);
+               if( port_array[port] == NULL ) {
+                       for (--port; port >= 0; --port) {
+                               tty_port_destroy(&port_array[port]->port);
+                               kfree(port_array[port]);
+                       }
+                       return;
+               }
+       }
+
+       /* give copy of port_array to all ports and add to device list  */
+       for ( port = 0; port < SCA_MAX_PORTS; ++port ) {
+               memcpy(port_array[port]->port_array,port_array,sizeof(port_array));
+               add_device( port_array[port] );
+               spin_lock_init(&port_array[port]->lock);
+       }
+
+       /* Allocate and claim adapter resources */
+       if ( !claim_resources(port_array[0]) ) {
+
+               alloc_dma_bufs(port_array[0]);
+
+               /* copy resource information from first port to others */
+               for ( port = 1; port < SCA_MAX_PORTS; ++port ) {
+                       port_array[port]->lock  = port_array[0]->lock;
+                       port_array[port]->irq_level     = port_array[0]->irq_level;
+                       port_array[port]->memory_base   = port_array[0]->memory_base;
+                       port_array[port]->sca_base      = port_array[0]->sca_base;
+                       port_array[port]->statctrl_base = port_array[0]->statctrl_base;
+                       port_array[port]->lcr_base      = port_array[0]->lcr_base;
+                       alloc_dma_bufs(port_array[port]);
+               }
+
+               if ( request_irq(port_array[0]->irq_level,
+                                       synclinkmp_interrupt,
+                                       port_array[0]->irq_flags,
+                                       port_array[0]->device_name,
+                                       port_array[0]) < 0 ) {
+                       printk( "%s(%d):%s Can't request interrupt, IRQ=%d\n",
+                               __FILE__,__LINE__,
+                               port_array[0]->device_name,
+                               port_array[0]->irq_level );
+               }
+               else {
+                       port_array[0]->irq_requested = true;
+                       adapter_test(port_array[0]);
+               }
+       }
+}
+
+static const struct tty_operations ops = {
+       .install = install,
+       .open = open,
+       .close = close,
+       .write = write,
+       .put_char = put_char,
+       .flush_chars = flush_chars,
+       .write_room = write_room,
+       .chars_in_buffer = chars_in_buffer,
+       .flush_buffer = flush_buffer,
+       .ioctl = ioctl,
+       .throttle = throttle,
+       .unthrottle = unthrottle,
+       .send_xchar = send_xchar,
+       .break_ctl = set_break,
+       .wait_until_sent = wait_until_sent,
+       .set_termios = set_termios,
+       .stop = tx_hold,
+       .start = tx_release,
+       .hangup = hangup,
+       .tiocmget = tiocmget,
+       .tiocmset = tiocmset,
+       .get_icount = get_icount,
+       .proc_fops = &synclinkmp_proc_fops,
+};
+
+
+static void synclinkmp_cleanup(void)
+{
+       int rc;
+       SLMP_INFO *info;
+       SLMP_INFO *tmp;
+
+       printk("Unloading %s %s\n", driver_name, driver_version);
+
+       if (serial_driver) {
+               if ((rc = tty_unregister_driver(serial_driver)))
+                       printk("%s(%d) failed to unregister tty driver err=%d\n",
+                              __FILE__,__LINE__,rc);
+               put_tty_driver(serial_driver);
+       }
+
+       /* reset devices */
+       info = synclinkmp_device_list;
+       while(info) {
+               reset_port(info);
+               info = info->next_device;
+       }
+
+       /* release devices */
+       info = synclinkmp_device_list;
+       while(info) {
+#if SYNCLINK_GENERIC_HDLC
+               hdlcdev_exit(info);
+#endif
+               free_dma_bufs(info);
+               free_tmp_rx_buf(info);
+               if ( info->port_num == 0 ) {
+                       if (info->sca_base)
+                               write_reg(info, LPR, 1); /* set low power mode */
+                       release_resources(info);
+               }
+               tmp = info;
+               info = info->next_device;
+               tty_port_destroy(&tmp->port);
+               kfree(tmp);
+       }
+
+       pci_unregister_driver(&synclinkmp_pci_driver);
+}
+
+/* Driver initialization entry point.
+ */
+
+static int __init synclinkmp_init(void)
+{
+       int rc;
+
+       if (break_on_load) {
+               synclinkmp_get_text_ptr();
+               BREAKPOINT();
+       }
+
+       printk("%s %s\n", driver_name, driver_version);
+
+       if ((rc = pci_register_driver(&synclinkmp_pci_driver)) < 0) {
+               printk("%s:failed to register PCI driver, error=%d\n",__FILE__,rc);
+               return rc;
+       }
+
+       serial_driver = alloc_tty_driver(128);
+       if (!serial_driver) {
+               rc = -ENOMEM;
+               goto error;
+       }
+
+       /* Initialize the tty_driver structure */
+
+       serial_driver->driver_name = "synclinkmp";
+       serial_driver->name = "ttySLM";
+       serial_driver->major = ttymajor;
+       serial_driver->minor_start = 64;
+       serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+       serial_driver->subtype = SERIAL_TYPE_NORMAL;
+       serial_driver->init_termios = tty_std_termios;
+       serial_driver->init_termios.c_cflag =
+               B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+       serial_driver->init_termios.c_ispeed = 9600;
+       serial_driver->init_termios.c_ospeed = 9600;
+       serial_driver->flags = TTY_DRIVER_REAL_RAW;
+       tty_set_operations(serial_driver, &ops);
+       if ((rc = tty_register_driver(serial_driver)) < 0) {
+               printk("%s(%d):Couldn't register serial driver\n",
+                       __FILE__,__LINE__);
+               put_tty_driver(serial_driver);
+               serial_driver = NULL;
+               goto error;
+       }
+
+       printk("%s %s, tty major#%d\n",
+               driver_name, driver_version,
+               serial_driver->major);
+
+       return 0;
+
+error:
+       synclinkmp_cleanup();
+       return rc;
+}
+
+static void __exit synclinkmp_exit(void)
+{
+       synclinkmp_cleanup();
+}
+
+module_init(synclinkmp_init);
+module_exit(synclinkmp_exit);
+
+/* Set the port for internal loopback mode.
+ * The TxCLK and RxCLK signals are generated from the BRG and
+ * the TxD is looped back to the RxD internally.
+ */
+static void enable_loopback(SLMP_INFO *info, int enable)
+{
+       if (enable) {
+               /* MD2 (Mode Register 2)
+                * 01..00  CNCT<1..0> Channel Connection 11=Local Loopback
+                */
+               write_reg(info, MD2, (unsigned char)(read_reg(info, MD2) | (BIT1 + BIT0)));
+
+               /* degate external TxC clock source */
+               info->port_array[0]->ctrlreg_value |= (BIT0 << (info->port_num * 2));
+               write_control_reg(info);
+
+               /* RXS/TXS (Rx/Tx clock source)
+                * 07      Reserved, must be 0
+                * 06..04  Clock Source, 100=BRG
+                * 03..00  Clock Divisor, 0000=1
+                */
+               write_reg(info, RXS, 0x40);
+               write_reg(info, TXS, 0x40);
+
+       } else {
+               /* MD2 (Mode Register 2)
+                * 01..00  CNCT<1..0> Channel connection, 0=normal
+                */
+               write_reg(info, MD2, (unsigned char)(read_reg(info, MD2) & ~(BIT1 + BIT0)));
+
+               /* RXS/TXS (Rx/Tx clock source)
+                * 07      Reserved, must be 0
+                * 06..04  Clock Source, 000=RxC/TxC Pin
+                * 03..00  Clock Divisor, 0000=1
+                */
+               write_reg(info, RXS, 0x00);
+               write_reg(info, TXS, 0x00);
+       }
+
+       /* set LinkSpeed if available, otherwise default to 2Mbps */
+       if (info->params.clock_speed)
+               set_rate(info, info->params.clock_speed);
+       else
+               set_rate(info, 3686400);
+}
+
+/* Set the baud rate register to the desired speed
+ *
+ *     data_rate       data rate of clock in bits per second
+ *                     A data rate of 0 disables the AUX clock.
+ */
+static void set_rate( SLMP_INFO *info, u32 data_rate )
+{
+               u32 TMCValue;
+               unsigned char BRValue;
+       u32 Divisor=0;
+
+       /* fBRG = fCLK/(TMC * 2^BR)
+        */
+       if (data_rate != 0) {
+               Divisor = 14745600/data_rate;
+               if (!Divisor)
+                       Divisor = 1;
+
+               TMCValue = Divisor;
+
+               BRValue = 0;
+               if (TMCValue != 1 && TMCValue != 2) {
+                       /* BRValue of 0 provides 50/50 duty cycle *only* when
+                        * TMCValue is 1 or 2. BRValue of 1 to 9 always provides
+                        * 50/50 duty cycle.
+                        */
+                       BRValue = 1;
+                       TMCValue >>= 1;
+               }
+
+               /* while TMCValue is too big for TMC register, divide
+                * by 2 and increment BR exponent.
+                */
+               for(; TMCValue > 256 && BRValue < 10; BRValue++)
+                       TMCValue >>= 1;
+
+               write_reg(info, TXS,
+                       (unsigned char)((read_reg(info, TXS) & 0xf0) | BRValue));
+               write_reg(info, RXS,
+                       (unsigned char)((read_reg(info, RXS) & 0xf0) | BRValue));
+               write_reg(info, TMC, (unsigned char)TMCValue);
+       }
+       else {
+               write_reg(info, TXS,0);
+               write_reg(info, RXS,0);
+               write_reg(info, TMC, 0);
+       }
+}
+
+/* Disable receiver
+ */
+static void rx_stop(SLMP_INFO *info)
+{
+       if (debug_level >= DEBUG_LEVEL_ISR)
+               printk("%s(%d):%s rx_stop()\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       write_reg(info, CMD, RXRESET);
+
+       info->ie0_value &= ~RXRDYE;
+       write_reg(info, IE0, info->ie0_value);  /* disable Rx data interrupts */
+
+       write_reg(info, RXDMA + DSR, 0);        /* disable Rx DMA */
+       write_reg(info, RXDMA + DCMD, SWABORT); /* reset/init Rx DMA */
+       write_reg(info, RXDMA + DIR, 0);        /* disable Rx DMA interrupts */
+
+       info->rx_enabled = false;
+       info->rx_overflow = false;
+}
+
+/* enable the receiver
+ */
+static void rx_start(SLMP_INFO *info)
+{
+       int i;
+
+       if (debug_level >= DEBUG_LEVEL_ISR)
+               printk("%s(%d):%s rx_start()\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       write_reg(info, CMD, RXRESET);
+
+       if ( info->params.mode == MGSL_MODE_HDLC ) {
+               /* HDLC, disabe IRQ on rxdata */
+               info->ie0_value &= ~RXRDYE;
+               write_reg(info, IE0, info->ie0_value);
+
+               /* Reset all Rx DMA buffers and program rx dma */
+               write_reg(info, RXDMA + DSR, 0);                /* disable Rx DMA */
+               write_reg(info, RXDMA + DCMD, SWABORT); /* reset/init Rx DMA */
+
+               for (i = 0; i < info->rx_buf_count; i++) {
+                       info->rx_buf_list[i].status = 0xff;
+
+                       // throttle to 4 shared memory writes at a time to prevent
+                       // hogging local bus (keep latency time for DMA requests low).
+                       if (!(i % 4))
+                               read_status_reg(info);
+               }
+               info->current_rx_buf = 0;
+
+               /* set current/1st descriptor address */
+               write_reg16(info, RXDMA + CDA,
+                       info->rx_buf_list_ex[0].phys_entry);
+
+               /* set new last rx descriptor address */
+               write_reg16(info, RXDMA + EDA,
+                       info->rx_buf_list_ex[info->rx_buf_count - 1].phys_entry);
+
+               /* set buffer length (shared by all rx dma data buffers) */
+               write_reg16(info, RXDMA + BFL, SCABUFSIZE);
+
+               write_reg(info, RXDMA + DIR, 0x60);     /* enable Rx DMA interrupts (EOM/BOF) */
+               write_reg(info, RXDMA + DSR, 0xf2);     /* clear Rx DMA IRQs, enable Rx DMA */
+       } else {
+               /* async, enable IRQ on rxdata */
+               info->ie0_value |= RXRDYE;
+               write_reg(info, IE0, info->ie0_value);
+       }
+
+       write_reg(info, CMD, RXENABLE);
+
+       info->rx_overflow = false;
+       info->rx_enabled = true;
+}
+
+/* Enable the transmitter and send a transmit frame if
+ * one is loaded in the DMA buffers.
+ */
+static void tx_start(SLMP_INFO *info)
+{
+       if (debug_level >= DEBUG_LEVEL_ISR)
+               printk("%s(%d):%s tx_start() tx_count=%d\n",
+                        __FILE__,__LINE__, info->device_name,info->tx_count );
+
+       if (!info->tx_enabled ) {
+               write_reg(info, CMD, TXRESET);
+               write_reg(info, CMD, TXENABLE);
+               info->tx_enabled = true;
+       }
+
+       if ( info->tx_count ) {
+
+               /* If auto RTS enabled and RTS is inactive, then assert */
+               /* RTS and set a flag indicating that the driver should */
+               /* negate RTS when the transmission completes. */
+
+               info->drop_rts_on_tx_done = false;
+
+               if (info->params.mode != MGSL_MODE_ASYNC) {
+
+                       if ( info->params.flags & HDLC_FLAG_AUTO_RTS ) {
+                               get_signals( info );
+                               if ( !(info->serial_signals & SerialSignal_RTS) ) {
+                                       info->serial_signals |= SerialSignal_RTS;
+                                       set_signals( info );
+                                       info->drop_rts_on_tx_done = true;
+                               }
+                       }
+
+                       write_reg16(info, TRC0,
+                               (unsigned short)(((tx_negate_fifo_level-1)<<8) + tx_active_fifo_level));
+
+                       write_reg(info, TXDMA + DSR, 0);                /* disable DMA channel */
+                       write_reg(info, TXDMA + DCMD, SWABORT); /* reset/init DMA channel */
+       
+                       /* set TX CDA (current descriptor address) */
+                       write_reg16(info, TXDMA + CDA,
+                               info->tx_buf_list_ex[0].phys_entry);
+       
+                       /* set TX EDA (last descriptor address) */
+                       write_reg16(info, TXDMA + EDA,
+                               info->tx_buf_list_ex[info->last_tx_buf].phys_entry);
+       
+                       /* enable underrun IRQ */
+                       info->ie1_value &= ~IDLE;
+                       info->ie1_value |= UDRN;
+                       write_reg(info, IE1, info->ie1_value);
+                       write_reg(info, SR1, (unsigned char)(IDLE + UDRN));
+       
+                       write_reg(info, TXDMA + DIR, 0x40);             /* enable Tx DMA interrupts (EOM) */
+                       write_reg(info, TXDMA + DSR, 0xf2);             /* clear Tx DMA IRQs, enable Tx DMA */
+       
+                       mod_timer(&info->tx_timer, jiffies +
+                                       msecs_to_jiffies(5000));
+               }
+               else {
+                       tx_load_fifo(info);
+                       /* async, enable IRQ on txdata */
+                       info->ie0_value |= TXRDYE;
+                       write_reg(info, IE0, info->ie0_value);
+               }
+
+               info->tx_active = true;
+       }
+}
+
+/* stop the transmitter and DMA
+ */
+static void tx_stop( SLMP_INFO *info )
+{
+       if (debug_level >= DEBUG_LEVEL_ISR)
+               printk("%s(%d):%s tx_stop()\n",
+                        __FILE__,__LINE__, info->device_name );
+
+       del_timer(&info->tx_timer);
+
+       write_reg(info, TXDMA + DSR, 0);                /* disable DMA channel */
+       write_reg(info, TXDMA + DCMD, SWABORT); /* reset/init DMA channel */
+
+       write_reg(info, CMD, TXRESET);
+
+       info->ie1_value &= ~(UDRN + IDLE);
+       write_reg(info, IE1, info->ie1_value);  /* disable tx status interrupts */
+       write_reg(info, SR1, (unsigned char)(IDLE + UDRN));     /* clear pending */
+
+       info->ie0_value &= ~TXRDYE;
+       write_reg(info, IE0, info->ie0_value);  /* disable tx data interrupts */
+
+       info->tx_enabled = false;
+       info->tx_active = false;
+}
+
+/* Fill the transmit FIFO until the FIFO is full or
+ * there is no more data to load.
+ */
+static void tx_load_fifo(SLMP_INFO *info)
+{
+       u8 TwoBytes[2];
+
+       /* do nothing is now tx data available and no XON/XOFF pending */
+
+       if ( !info->tx_count && !info->x_char )
+               return;
+
+       /* load the Transmit FIFO until FIFOs full or all data sent */
+
+       while( info->tx_count && (read_reg(info,SR0) & BIT1) ) {
+
+               /* there is more space in the transmit FIFO and */
+               /* there is more data in transmit buffer */
+
+               if ( (info->tx_count > 1) && !info->x_char ) {
+                       /* write 16-bits */
+                       TwoBytes[0] = info->tx_buf[info->tx_get++];
+                       if (info->tx_get >= info->max_frame_size)
+                               info->tx_get -= info->max_frame_size;
+                       TwoBytes[1] = info->tx_buf[info->tx_get++];
+                       if (info->tx_get >= info->max_frame_size)
+                               info->tx_get -= info->max_frame_size;
+
+                       write_reg16(info, TRB, *((u16 *)TwoBytes));
+
+                       info->tx_count -= 2;
+                       info->icount.tx += 2;
+               } else {
+                       /* only 1 byte left to transmit or 1 FIFO slot left */
+
+                       if (info->x_char) {
+                               /* transmit pending high priority char */
+                               write_reg(info, TRB, info->x_char);
+                               info->x_char = 0;
+                       } else {
+                               write_reg(info, TRB, info->tx_buf[info->tx_get++]);
+                               if (info->tx_get >= info->max_frame_size)
+                                       info->tx_get -= info->max_frame_size;
+                               info->tx_count--;
+                       }
+                       info->icount.tx++;
+               }
+       }
+}
+
+/* Reset a port to a known state
+ */
+static void reset_port(SLMP_INFO *info)
+{
+       if (info->sca_base) {
+
+               tx_stop(info);
+               rx_stop(info);
+
+               info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
+               set_signals(info);
+
+               /* disable all port interrupts */
+               info->ie0_value = 0;
+               info->ie1_value = 0;
+               info->ie2_value = 0;
+               write_reg(info, IE0, info->ie0_value);
+               write_reg(info, IE1, info->ie1_value);
+               write_reg(info, IE2, info->ie2_value);
+
+               write_reg(info, CMD, CHRESET);
+       }
+}
+
+/* Reset all the ports to a known state.
+ */
+static void reset_adapter(SLMP_INFO *info)
+{
+       int i;
+
+       for ( i=0; i < SCA_MAX_PORTS; ++i) {
+               if (info->port_array[i])
+                       reset_port(info->port_array[i]);
+       }
+}
+
+/* Program port for asynchronous communications.
+ */
+static void async_mode(SLMP_INFO *info)
+{
+
+       unsigned char RegValue;
+
+       tx_stop(info);
+       rx_stop(info);
+
+       /* MD0, Mode Register 0
+        *
+        * 07..05  PRCTL<2..0>, Protocol Mode, 000=async
+        * 04      AUTO, Auto-enable (RTS/CTS/DCD)
+        * 03      Reserved, must be 0
+        * 02      CRCCC, CRC Calculation, 0=disabled
+        * 01..00  STOP<1..0> Stop bits (00=1,10=2)
+        *
+        * 0000 0000
+        */
+       RegValue = 0x00;
+       if (info->params.stop_bits != 1)
+               RegValue |= BIT1;
+       write_reg(info, MD0, RegValue);
+
+       /* MD1, Mode Register 1
+        *
+        * 07..06  BRATE<1..0>, bit rate, 00=1/1 01=1/16 10=1/32 11=1/64
+        * 05..04  TXCHR<1..0>, tx char size, 00=8 bits,01=7,10=6,11=5
+        * 03..02  RXCHR<1..0>, rx char size
+        * 01..00  PMPM<1..0>, Parity mode, 00=none 10=even 11=odd
+        *
+        * 0100 0000
+        */
+       RegValue = 0x40;
+       switch (info->params.data_bits) {
+       case 7: RegValue |= BIT4 + BIT2; break;
+       case 6: RegValue |= BIT5 + BIT3; break;
+       case 5: RegValue |= BIT5 + BIT4 + BIT3 + BIT2; break;
+       }
+       if (info->params.parity != ASYNC_PARITY_NONE) {
+               RegValue |= BIT1;
+               if (info->params.parity == ASYNC_PARITY_ODD)
+                       RegValue |= BIT0;
+       }
+       write_reg(info, MD1, RegValue);
+
+       /* MD2, Mode Register 2
+        *
+        * 07..02  Reserved, must be 0
+        * 01..00  CNCT<1..0> Channel connection, 00=normal 11=local loopback
+        *
+        * 0000 0000
+        */
+       RegValue = 0x00;
+       if (info->params.loopback)
+               RegValue |= (BIT1 + BIT0);
+       write_reg(info, MD2, RegValue);
+
+       /* RXS, Receive clock source
+        *
+        * 07      Reserved, must be 0
+        * 06..04  RXCS<2..0>, clock source, 000=RxC Pin, 100=BRG, 110=DPLL
+        * 03..00  RXBR<3..0>, rate divisor, 0000=1
+        */
+       RegValue=BIT6;
+       write_reg(info, RXS, RegValue);
+
+       /* TXS, Transmit clock source
+        *
+        * 07      Reserved, must be 0
+        * 06..04  RXCS<2..0>, clock source, 000=TxC Pin, 100=BRG, 110=Receive Clock
+        * 03..00  RXBR<3..0>, rate divisor, 0000=1
+        */
+       RegValue=BIT6;
+       write_reg(info, TXS, RegValue);
+
+       /* Control Register
+        *
+        * 6,4,2,0  CLKSEL<3..0>, 0 = TcCLK in, 1 = Auxclk out
+        */
+       info->port_array[0]->ctrlreg_value |= (BIT0 << (info->port_num * 2));
+       write_control_reg(info);
+
+       tx_set_idle(info);
+
+       /* RRC Receive Ready Control 0
+        *
+        * 07..05  Reserved, must be 0
+        * 04..00  RRC<4..0> Rx FIFO trigger active 0x00 = 1 byte
+        */
+       write_reg(info, RRC, 0x00);
+
+       /* TRC0 Transmit Ready Control 0
+        *
+        * 07..05  Reserved, must be 0
+        * 04..00  TRC<4..0> Tx FIFO trigger active 0x10 = 16 bytes
+        */
+       write_reg(info, TRC0, 0x10);
+
+       /* TRC1 Transmit Ready Control 1
+        *
+        * 07..05  Reserved, must be 0
+        * 04..00  TRC<4..0> Tx FIFO trigger inactive 0x1e = 31 bytes (full-1)
+        */
+       write_reg(info, TRC1, 0x1e);
+
+       /* CTL, MSCI control register
+        *
+        * 07..06  Reserved, set to 0
+        * 05      UDRNC, underrun control, 0=abort 1=CRC+flag (HDLC/BSC)
+        * 04      IDLC, idle control, 0=mark 1=idle register
+        * 03      BRK, break, 0=off 1 =on (async)
+        * 02      SYNCLD, sync char load enable (BSC) 1=enabled
+        * 01      GOP, go active on poll (LOOP mode) 1=enabled
+        * 00      RTS, RTS output control, 0=active 1=inactive
+        *
+        * 0001 0001
+        */
+       RegValue = 0x10;
+       if (!(info->serial_signals & SerialSignal_RTS))
+               RegValue |= 0x01;
+       write_reg(info, CTL, RegValue);
+
+       /* enable status interrupts */
+       info->ie0_value |= TXINTE + RXINTE;
+       write_reg(info, IE0, info->ie0_value);
+
+       /* enable break detect interrupt */
+       info->ie1_value = BRKD;
+       write_reg(info, IE1, info->ie1_value);
+
+       /* enable rx overrun interrupt */
+       info->ie2_value = OVRN;
+       write_reg(info, IE2, info->ie2_value);
+
+       set_rate( info, info->params.data_rate * 16 );
+}
+
+/* Program the SCA for HDLC communications.
+ */
+static void hdlc_mode(SLMP_INFO *info)
+{
+       unsigned char RegValue;
+       u32 DpllDivisor;
+
+       // Can't use DPLL because SCA outputs recovered clock on RxC when
+       // DPLL mode selected. This causes output contention with RxC receiver.
+       // Use of DPLL would require external hardware to disable RxC receiver
+       // when DPLL mode selected.
+       info->params.flags &= ~(HDLC_FLAG_TXC_DPLL + HDLC_FLAG_RXC_DPLL);
+
+       /* disable DMA interrupts */
+       write_reg(info, TXDMA + DIR, 0);
+       write_reg(info, RXDMA + DIR, 0);
+
+       /* MD0, Mode Register 0
+        *
+        * 07..05  PRCTL<2..0>, Protocol Mode, 100=HDLC
+        * 04      AUTO, Auto-enable (RTS/CTS/DCD)
+        * 03      Reserved, must be 0
+        * 02      CRCCC, CRC Calculation, 1=enabled
+        * 01      CRC1, CRC selection, 0=CRC-16,1=CRC-CCITT-16
+        * 00      CRC0, CRC initial value, 1 = all 1s
+        *
+        * 1000 0001
+        */
+       RegValue = 0x81;
+       if (info->params.flags & HDLC_FLAG_AUTO_CTS)
+               RegValue |= BIT4;
+       if (info->params.flags & HDLC_FLAG_AUTO_DCD)
+               RegValue |= BIT4;
+       if (info->params.crc_type == HDLC_CRC_16_CCITT)
+               RegValue |= BIT2 + BIT1;
+       write_reg(info, MD0, RegValue);
+
+       /* MD1, Mode Register 1
+        *
+        * 07..06  ADDRS<1..0>, Address detect, 00=no addr check
+        * 05..04  TXCHR<1..0>, tx char size, 00=8 bits
+        * 03..02  RXCHR<1..0>, rx char size, 00=8 bits
+        * 01..00  PMPM<1..0>, Parity mode, 00=no parity
+        *
+        * 0000 0000
+        */
+       RegValue = 0x00;
+       write_reg(info, MD1, RegValue);
+
+       /* MD2, Mode Register 2
+        *
+        * 07      NRZFM, 0=NRZ, 1=FM
+        * 06..05  CODE<1..0> Encoding, 00=NRZ
+        * 04..03  DRATE<1..0> DPLL Divisor, 00=8
+        * 02      Reserved, must be 0
+        * 01..00  CNCT<1..0> Channel connection, 0=normal
+        *
+        * 0000 0000
+        */
+       RegValue = 0x00;
+       switch(info->params.encoding) {
+       case HDLC_ENCODING_NRZI:          RegValue |= BIT5; break;
+       case HDLC_ENCODING_BIPHASE_MARK:  RegValue |= BIT7 + BIT5; break; /* aka FM1 */
+       case HDLC_ENCODING_BIPHASE_SPACE: RegValue |= BIT7 + BIT6; break; /* aka FM0 */
+       case HDLC_ENCODING_BIPHASE_LEVEL: RegValue |= BIT7; break;      /* aka Manchester */
+#if 0
+       case HDLC_ENCODING_NRZB:                                        /* not supported */
+       case HDLC_ENCODING_NRZI_MARK:                                   /* not supported */
+       case HDLC_ENCODING_DIFF_BIPHASE_LEVEL:                          /* not supported */
+#endif
+       }
+       if ( info->params.flags & HDLC_FLAG_DPLL_DIV16 ) {
+               DpllDivisor = 16;
+               RegValue |= BIT3;
+       } else if ( info->params.flags & HDLC_FLAG_DPLL_DIV8 ) {
+               DpllDivisor = 8;
+       } else {
+               DpllDivisor = 32;
+               RegValue |= BIT4;
+       }
+       write_reg(info, MD2, RegValue);
+
+
+       /* RXS, Receive clock source
+        *
+        * 07      Reserved, must be 0
+        * 06..04  RXCS<2..0>, clock source, 000=RxC Pin, 100=BRG, 110=DPLL
+        * 03..00  RXBR<3..0>, rate divisor, 0000=1
+        */
+       RegValue=0;
+       if (info->params.flags & HDLC_FLAG_RXC_BRG)
+               RegValue |= BIT6;
+       if (info->params.flags & HDLC_FLAG_RXC_DPLL)
+               RegValue |= BIT6 + BIT5;
+       write_reg(info, RXS, RegValue);
+
+       /* TXS, Transmit clock source
+        *
+        * 07      Reserved, must be 0
+        * 06..04  RXCS<2..0>, clock source, 000=TxC Pin, 100=BRG, 110=Receive Clock
+        * 03..00  RXBR<3..0>, rate divisor, 0000=1
+        */
+       RegValue=0;
+       if (info->params.flags & HDLC_FLAG_TXC_BRG)
+               RegValue |= BIT6;
+       if (info->params.flags & HDLC_FLAG_TXC_DPLL)
+               RegValue |= BIT6 + BIT5;
+       write_reg(info, TXS, RegValue);
+
+       if (info->params.flags & HDLC_FLAG_RXC_DPLL)
+               set_rate(info, info->params.clock_speed * DpllDivisor);
+       else
+               set_rate(info, info->params.clock_speed);
+
+       /* GPDATA (General Purpose I/O Data Register)
+        *
+        * 6,4,2,0  CLKSEL<3..0>, 0 = TcCLK in, 1 = Auxclk out
+        */
+       if (info->params.flags & HDLC_FLAG_TXC_BRG)
+               info->port_array[0]->ctrlreg_value |= (BIT0 << (info->port_num * 2));
+       else
+               info->port_array[0]->ctrlreg_value &= ~(BIT0 << (info->port_num * 2));
+       write_control_reg(info);
+
+       /* RRC Receive Ready Control 0
+        *
+        * 07..05  Reserved, must be 0
+        * 04..00  RRC<4..0> Rx FIFO trigger active
+        */
+       write_reg(info, RRC, rx_active_fifo_level);
+
+       /* TRC0 Transmit Ready Control 0
+        *
+        * 07..05  Reserved, must be 0
+        * 04..00  TRC<4..0> Tx FIFO trigger active
+        */
+       write_reg(info, TRC0, tx_active_fifo_level);
+
+       /* TRC1 Transmit Ready Control 1
+        *
+        * 07..05  Reserved, must be 0
+        * 04..00  TRC<4..0> Tx FIFO trigger inactive 0x1f = 32 bytes (full)
+        */
+       write_reg(info, TRC1, (unsigned char)(tx_negate_fifo_level - 1));
+
+       /* DMR, DMA Mode Register
+        *
+        * 07..05  Reserved, must be 0
+        * 04      TMOD, Transfer Mode: 1=chained-block
+        * 03      Reserved, must be 0
+        * 02      NF, Number of Frames: 1=multi-frame
+        * 01      CNTE, Frame End IRQ Counter enable: 0=disabled
+        * 00      Reserved, must be 0
+        *
+        * 0001 0100
+        */
+       write_reg(info, TXDMA + DMR, 0x14);
+       write_reg(info, RXDMA + DMR, 0x14);
+
+       /* Set chain pointer base (upper 8 bits of 24 bit addr) */
+       write_reg(info, RXDMA + CPB,
+               (unsigned char)(info->buffer_list_phys >> 16));
+
+       /* Set chain pointer base (upper 8 bits of 24 bit addr) */
+       write_reg(info, TXDMA + CPB,
+               (unsigned char)(info->buffer_list_phys >> 16));
+
+       /* enable status interrupts. other code enables/disables
+        * the individual sources for these two interrupt classes.
+        */
+       info->ie0_value |= TXINTE + RXINTE;
+       write_reg(info, IE0, info->ie0_value);
+
+       /* CTL, MSCI control register
+        *
+        * 07..06  Reserved, set to 0
+        * 05      UDRNC, underrun control, 0=abort 1=CRC+flag (HDLC/BSC)
+        * 04      IDLC, idle control, 0=mark 1=idle register
+        * 03      BRK, break, 0=off 1 =on (async)
+        * 02      SYNCLD, sync char load enable (BSC) 1=enabled
+        * 01      GOP, go active on poll (LOOP mode) 1=enabled
+        * 00      RTS, RTS output control, 0=active 1=inactive
+        *
+        * 0001 0001
+        */
+       RegValue = 0x10;
+       if (!(info->serial_signals & SerialSignal_RTS))
+               RegValue |= 0x01;
+       write_reg(info, CTL, RegValue);
+
+       /* preamble not supported ! */
+
+       tx_set_idle(info);
+       tx_stop(info);
+       rx_stop(info);
+
+       set_rate(info, info->params.clock_speed);
+
+       if (info->params.loopback)
+               enable_loopback(info,1);
+}
+
+/* Set the transmit HDLC idle mode
+ */
+static void tx_set_idle(SLMP_INFO *info)
+{
+       unsigned char RegValue = 0xff;
+
+       /* Map API idle mode to SCA register bits */
+       switch(info->idle_mode) {
+       case HDLC_TXIDLE_FLAGS:                 RegValue = 0x7e; break;
+       case HDLC_TXIDLE_ALT_ZEROS_ONES:        RegValue = 0xaa; break;
+       case HDLC_TXIDLE_ZEROS:                 RegValue = 0x00; break;
+       case HDLC_TXIDLE_ONES:                  RegValue = 0xff; break;
+       case HDLC_TXIDLE_ALT_MARK_SPACE:        RegValue = 0xaa; break;
+       case HDLC_TXIDLE_SPACE:                 RegValue = 0x00; break;
+       case HDLC_TXIDLE_MARK:                  RegValue = 0xff; break;
+       }
+
+       write_reg(info, IDL, RegValue);
+}
+
+/* Query the adapter for the state of the V24 status (input) signals.
+ */
+static void get_signals(SLMP_INFO *info)
+{
+       u16 status = read_reg(info, SR3);
+       u16 gpstatus = read_status_reg(info);
+       u16 testbit;
+
+       /* clear all serial signals except RTS and DTR */
+       info->serial_signals &= SerialSignal_RTS | SerialSignal_DTR;
+
+       /* set serial signal bits to reflect MISR */
+
+       if (!(status & BIT3))
+               info->serial_signals |= SerialSignal_CTS;
+
+       if ( !(status & BIT2))
+               info->serial_signals |= SerialSignal_DCD;
+
+       testbit = BIT1 << (info->port_num * 2); // Port 0..3 RI is GPDATA<1,3,5,7>
+       if (!(gpstatus & testbit))
+               info->serial_signals |= SerialSignal_RI;
+
+       testbit = BIT0 << (info->port_num * 2); // Port 0..3 DSR is GPDATA<0,2,4,6>
+       if (!(gpstatus & testbit))
+               info->serial_signals |= SerialSignal_DSR;
+}
+
+/* Set the state of RTS and DTR based on contents of
+ * serial_signals member of device context.
+ */
+static void set_signals(SLMP_INFO *info)
+{
+       unsigned char RegValue;
+       u16 EnableBit;
+
+       RegValue = read_reg(info, CTL);
+       if (info->serial_signals & SerialSignal_RTS)
+               RegValue &= ~BIT0;
+       else
+               RegValue |= BIT0;
+       write_reg(info, CTL, RegValue);
+
+       // Port 0..3 DTR is ctrl reg <1,3,5,7>
+       EnableBit = BIT1 << (info->port_num*2);
+       if (info->serial_signals & SerialSignal_DTR)
+               info->port_array[0]->ctrlreg_value &= ~EnableBit;
+       else
+               info->port_array[0]->ctrlreg_value |= EnableBit;
+       write_control_reg(info);
+}
+
+/*******************/
+/* DMA Buffer Code */
+/*******************/
+
+/* Set the count for all receive buffers to SCABUFSIZE
+ * and set the current buffer to the first buffer. This effectively
+ * makes all buffers free and discards any data in buffers.
+ */
+static void rx_reset_buffers(SLMP_INFO *info)
+{
+       rx_free_frame_buffers(info, 0, info->rx_buf_count - 1);
+}
+
+/* Free the buffers used by a received frame
+ *
+ * info   pointer to device instance data
+ * first  index of 1st receive buffer of frame
+ * last   index of last receive buffer of frame
+ */
+static void rx_free_frame_buffers(SLMP_INFO *info, unsigned int first, unsigned int last)
+{
+       bool done = false;
+
+       while(!done) {
+               /* reset current buffer for reuse */
+               info->rx_buf_list[first].status = 0xff;
+
+               if (first == last) {
+                       done = true;
+                       /* set new last rx descriptor address */
+                       write_reg16(info, RXDMA + EDA, info->rx_buf_list_ex[first].phys_entry);
+               }
+
+               first++;
+               if (first == info->rx_buf_count)
+                       first = 0;
+       }
+
+       /* set current buffer to next buffer after last buffer of frame */
+       info->current_rx_buf = first;
+}
+
+/* Return a received frame from the receive DMA buffers.
+ * Only frames received without errors are returned.
+ *
+ * Return Value:       true if frame returned, otherwise false
+ */
+static bool rx_get_frame(SLMP_INFO *info)
+{
+       unsigned int StartIndex, EndIndex;      /* index of 1st and last buffers of Rx frame */
+       unsigned short status;
+       unsigned int framesize = 0;
+       bool ReturnCode = false;
+       unsigned long flags;
+       struct tty_struct *tty = info->port.tty;
+       unsigned char addr_field = 0xff;
+       SCADESC *desc;
+       SCADESC_EX *desc_ex;
+
+CheckAgain:
+       /* assume no frame returned, set zero length */
+       framesize = 0;
+       addr_field = 0xff;
+
+       /*
+        * current_rx_buf points to the 1st buffer of the next available
+        * receive frame. To find the last buffer of the frame look for
+        * a non-zero status field in the buffer entries. (The status
+        * field is set by the 16C32 after completing a receive frame.
+        */
+       StartIndex = EndIndex = info->current_rx_buf;
+
+       for ( ;; ) {
+               desc = &info->rx_buf_list[EndIndex];
+               desc_ex = &info->rx_buf_list_ex[EndIndex];
+
+               if (desc->status == 0xff)
+                       goto Cleanup;   /* current desc still in use, no frames available */
+
+               if (framesize == 0 && info->params.addr_filter != 0xff)
+                       addr_field = desc_ex->virt_addr[0];
+
+               framesize += desc->length;
+
+               /* Status != 0 means last buffer of frame */
+               if (desc->status)
+                       break;
+
+               EndIndex++;
+               if (EndIndex == info->rx_buf_count)
+                       EndIndex = 0;
+
+               if (EndIndex == info->current_rx_buf) {
+                       /* all buffers have been 'used' but none mark      */
+                       /* the end of a frame. Reset buffers and receiver. */
+                       if ( info->rx_enabled ){
+                               spin_lock_irqsave(&info->lock,flags);
+                               rx_start(info);
+                               spin_unlock_irqrestore(&info->lock,flags);
+                       }
+                       goto Cleanup;
+               }
+
+       }
+
+       /* check status of receive frame */
+
+       /* frame status is byte stored after frame data
+        *
+        * 7 EOM (end of msg), 1 = last buffer of frame
+        * 6 Short Frame, 1 = short frame
+        * 5 Abort, 1 = frame aborted
+        * 4 Residue, 1 = last byte is partial
+        * 3 Overrun, 1 = overrun occurred during frame reception
+        * 2 CRC,     1 = CRC error detected
+        *
+        */
+       status = desc->status;
+
+       /* ignore CRC bit if not using CRC (bit is undefined) */
+       /* Note:CRC is not save to data buffer */
+       if (info->params.crc_type == HDLC_CRC_NONE)
+               status &= ~BIT2;
+
+       if (framesize == 0 ||
+                (addr_field != 0xff && addr_field != info->params.addr_filter)) {
+               /* discard 0 byte frames, this seems to occur sometime
+                * when remote is idling flags.
+                */
+               rx_free_frame_buffers(info, StartIndex, EndIndex);
+               goto CheckAgain;
+       }
+
+       if (framesize < 2)
+               status |= BIT6;
+
+       if (status & (BIT6+BIT5+BIT3+BIT2)) {
+               /* received frame has errors,
+                * update counts and mark frame size as 0
+                */
+               if (status & BIT6)
+                       info->icount.rxshort++;
+               else if (status & BIT5)
+                       info->icount.rxabort++;
+               else if (status & BIT3)
+                       info->icount.rxover++;
+               else
+                       info->icount.rxcrc++;
+
+               framesize = 0;
+#if SYNCLINK_GENERIC_HDLC
+               {
+                       info->netdev->stats.rx_errors++;
+                       info->netdev->stats.rx_frame_errors++;
+               }
+#endif
+       }
+
+       if ( debug_level >= DEBUG_LEVEL_BH )
+               printk("%s(%d):%s rx_get_frame() status=%04X size=%d\n",
+                       __FILE__,__LINE__,info->device_name,status,framesize);
+
+       if ( debug_level >= DEBUG_LEVEL_DATA )
+               trace_block(info,info->rx_buf_list_ex[StartIndex].virt_addr,
+                       min_t(unsigned int, framesize, SCABUFSIZE), 0);
+
+       if (framesize) {
+               if (framesize > info->max_frame_size)
+                       info->icount.rxlong++;
+               else {
+                       /* copy dma buffer(s) to contiguous intermediate buffer */
+                       int copy_count = framesize;
+                       int index = StartIndex;
+                       unsigned char *ptmp = info->tmp_rx_buf;
+                       info->tmp_rx_buf_count = framesize;
+
+                       info->icount.rxok++;
+
+                       while(copy_count) {
+                               int partial_count = min(copy_count,SCABUFSIZE);
+                               memcpy( ptmp,
+                                       info->rx_buf_list_ex[index].virt_addr,
+                                       partial_count );
+                               ptmp += partial_count;
+                               copy_count -= partial_count;
+
+                               if ( ++index == info->rx_buf_count )
+                                       index = 0;
+                       }
+
+#if SYNCLINK_GENERIC_HDLC
+                       if (info->netcount)
+                               hdlcdev_rx(info,info->tmp_rx_buf,framesize);
+                       else
+#endif
+                               ldisc_receive_buf(tty,info->tmp_rx_buf,
+                                                 info->flag_buf, framesize);
+               }
+       }
+       /* Free the buffers used by this frame. */
+       rx_free_frame_buffers( info, StartIndex, EndIndex );
+
+       ReturnCode = true;
+
+Cleanup:
+       if ( info->rx_enabled && info->rx_overflow ) {
+               /* Receiver is enabled, but needs to restarted due to
+                * rx buffer overflow. If buffers are empty, restart receiver.
+                */
+               if (info->rx_buf_list[EndIndex].status == 0xff) {
+                       spin_lock_irqsave(&info->lock,flags);
+                       rx_start(info);
+                       spin_unlock_irqrestore(&info->lock,flags);
+               }
+       }
+
+       return ReturnCode;
+}
+
+/* load the transmit DMA buffer with data
+ */
+static void tx_load_dma_buffer(SLMP_INFO *info, const char *buf, unsigned int count)
+{
+       unsigned short copy_count;
+       unsigned int i = 0;
+       SCADESC *desc;
+       SCADESC_EX *desc_ex;
+
+       if ( debug_level >= DEBUG_LEVEL_DATA )
+               trace_block(info, buf, min_t(unsigned int, count, SCABUFSIZE), 1);
+
+       /* Copy source buffer to one or more DMA buffers, starting with
+        * the first transmit dma buffer.
+        */
+       for(i=0;;)
+       {
+               copy_count = min_t(unsigned int, count, SCABUFSIZE);
+
+               desc = &info->tx_buf_list[i];
+               desc_ex = &info->tx_buf_list_ex[i];
+
+               load_pci_memory(info, desc_ex->virt_addr,buf,copy_count);
+
+               desc->length = copy_count;
+               desc->status = 0;
+
+               buf += copy_count;
+               count -= copy_count;
+
+               if (!count)
+                       break;
+
+               i++;
+               if (i >= info->tx_buf_count)
+                       i = 0;
+       }
+
+       info->tx_buf_list[i].status = 0x81;     /* set EOM and EOT status */
+       info->last_tx_buf = ++i;
+}
+
+static bool register_test(SLMP_INFO *info)
+{
+       static unsigned char testval[] = {0x00, 0xff, 0xaa, 0x55, 0x69, 0x96};
+       static unsigned int count = ARRAY_SIZE(testval);
+       unsigned int i;
+       bool rc = true;
+       unsigned long flags;
+
+       spin_lock_irqsave(&info->lock,flags);
+       reset_port(info);
+
+       /* assume failure */
+       info->init_error = DiagStatus_AddressFailure;
+
+       /* Write bit patterns to various registers but do it out of */
+       /* sync, then read back and verify values. */
+
+       for (i = 0 ; i < count ; i++) {
+               write_reg(info, TMC, testval[i]);
+               write_reg(info, IDL, testval[(i+1)%count]);
+               write_reg(info, SA0, testval[(i+2)%count]);
+               write_reg(info, SA1, testval[(i+3)%count]);
+
+               if ( (read_reg(info, TMC) != testval[i]) ||
+                         (read_reg(info, IDL) != testval[(i+1)%count]) ||
+                         (read_reg(info, SA0) != testval[(i+2)%count]) ||
+                         (read_reg(info, SA1) != testval[(i+3)%count]) )
+               {
+                       rc = false;
+                       break;
+               }
+       }
+
+       reset_port(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       return rc;
+}
+
+static bool irq_test(SLMP_INFO *info)
+{
+       unsigned long timeout;
+       unsigned long flags;
+
+       unsigned char timer = (info->port_num & 1) ? TIMER2 : TIMER0;
+
+       spin_lock_irqsave(&info->lock,flags);
+       reset_port(info);
+
+       /* assume failure */
+       info->init_error = DiagStatus_IrqFailure;
+       info->irq_occurred = false;
+
+       /* setup timer0 on SCA0 to interrupt */
+
+       /* IER2<7..4> = timer<3..0> interrupt enables (1=enabled) */
+       write_reg(info, IER2, (unsigned char)((info->port_num & 1) ? BIT6 : BIT4));
+
+       write_reg(info, (unsigned char)(timer + TEPR), 0);      /* timer expand prescale */
+       write_reg16(info, (unsigned char)(timer + TCONR), 1);   /* timer constant */
+
+
+       /* TMCS, Timer Control/Status Register
+        *
+        * 07      CMF, Compare match flag (read only) 1=match
+        * 06      ECMI, CMF Interrupt Enable: 1=enabled
+        * 05      Reserved, must be 0
+        * 04      TME, Timer Enable
+        * 03..00  Reserved, must be 0
+        *
+        * 0101 0000
+        */
+       write_reg(info, (unsigned char)(timer + TMCS), 0x50);
+
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       timeout=100;
+       while( timeout-- && !info->irq_occurred ) {
+               msleep_interruptible(10);
+       }
+
+       spin_lock_irqsave(&info->lock,flags);
+       reset_port(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       return info->irq_occurred;
+}
+
+/* initialize individual SCA device (2 ports)
+ */
+static bool sca_init(SLMP_INFO *info)
+{
+       /* set wait controller to single mem partition (low), no wait states */
+       write_reg(info, PABR0, 0);      /* wait controller addr boundary 0 */
+       write_reg(info, PABR1, 0);      /* wait controller addr boundary 1 */
+       write_reg(info, WCRL, 0);       /* wait controller low range */
+       write_reg(info, WCRM, 0);       /* wait controller mid range */
+       write_reg(info, WCRH, 0);       /* wait controller high range */
+
+       /* DPCR, DMA Priority Control
+        *
+        * 07..05  Not used, must be 0
+        * 04      BRC, bus release condition: 0=all transfers complete
+        * 03      CCC, channel change condition: 0=every cycle
+        * 02..00  PR<2..0>, priority 100=round robin
+        *
+        * 00000100 = 0x04
+        */
+       write_reg(info, DPCR, dma_priority);
+
+       /* DMA Master Enable, BIT7: 1=enable all channels */
+       write_reg(info, DMER, 0x80);
+
+       /* enable all interrupt classes */
+       write_reg(info, IER0, 0xff);    /* TxRDY,RxRDY,TxINT,RxINT (ports 0-1) */
+       write_reg(info, IER1, 0xff);    /* DMIB,DMIA (channels 0-3) */
+       write_reg(info, IER2, 0xf0);    /* TIRQ (timers 0-3) */
+
+       /* ITCR, interrupt control register
+        * 07      IPC, interrupt priority, 0=MSCI->DMA
+        * 06..05  IAK<1..0>, Acknowledge cycle, 00=non-ack cycle
+        * 04      VOS, Vector Output, 0=unmodified vector
+        * 03..00  Reserved, must be 0
+        */
+       write_reg(info, ITCR, 0);
+
+       return true;
+}
+
+/* initialize adapter hardware
+ */
+static bool init_adapter(SLMP_INFO *info)
+{
+       int i;
+
+       /* Set BIT30 of Local Control Reg 0x50 to reset SCA */
+       volatile u32 *MiscCtrl = (u32 *)(info->lcr_base + 0x50);
+       u32 readval;
+
+       info->misc_ctrl_value |= BIT30;
+       *MiscCtrl = info->misc_ctrl_value;
+
+       /*
+        * Force at least 170ns delay before clearing
+        * reset bit. Each read from LCR takes at least
+        * 30ns so 10 times for 300ns to be safe.
+        */
+       for(i=0;i<10;i++)
+               readval = *MiscCtrl;
+
+       info->misc_ctrl_value &= ~BIT30;
+       *MiscCtrl = info->misc_ctrl_value;
+
+       /* init control reg (all DTRs off, all clksel=input) */
+       info->ctrlreg_value = 0xaa;
+       write_control_reg(info);
+
+       {
+               volatile u32 *LCR1BRDR = (u32 *)(info->lcr_base + 0x2c);
+               lcr1_brdr_value &= ~(BIT5 + BIT4 + BIT3);
+
+               switch(read_ahead_count)
+               {
+               case 16:
+                       lcr1_brdr_value |= BIT5 + BIT4 + BIT3;
+                       break;
+               case 8:
+                       lcr1_brdr_value |= BIT5 + BIT4;
+                       break;
+               case 4:
+                       lcr1_brdr_value |= BIT5 + BIT3;
+                       break;
+               case 0:
+                       lcr1_brdr_value |= BIT5;
+                       break;
+               }
+
+               *LCR1BRDR = lcr1_brdr_value;
+               *MiscCtrl = misc_ctrl_value;
+       }
+
+       sca_init(info->port_array[0]);
+       sca_init(info->port_array[2]);
+
+       return true;
+}
+
+/* Loopback an HDLC frame to test the hardware
+ * interrupt and DMA functions.
+ */
+static bool loopback_test(SLMP_INFO *info)
+{
+#define TESTFRAMESIZE 20
+
+       unsigned long timeout;
+       u16 count = TESTFRAMESIZE;
+       unsigned char buf[TESTFRAMESIZE];
+       bool rc = false;
+       unsigned long flags;
+
+       struct tty_struct *oldtty = info->port.tty;
+       u32 speed = info->params.clock_speed;
+
+       info->params.clock_speed = 3686400;
+       info->port.tty = NULL;
+
+       /* assume failure */
+       info->init_error = DiagStatus_DmaFailure;
+
+       /* build and send transmit frame */
+       for (count = 0; count < TESTFRAMESIZE;++count)
+               buf[count] = (unsigned char)count;
+
+       memset(info->tmp_rx_buf,0,TESTFRAMESIZE);
+
+       /* program hardware for HDLC and enabled receiver */
+       spin_lock_irqsave(&info->lock,flags);
+       hdlc_mode(info);
+       enable_loopback(info,1);
+               rx_start(info);
+       info->tx_count = count;
+       tx_load_dma_buffer(info,buf,count);
+       tx_start(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       /* wait for receive complete */
+       /* Set a timeout for waiting for interrupt. */
+       for ( timeout = 100; timeout; --timeout ) {
+               msleep_interruptible(10);
+
+               if (rx_get_frame(info)) {
+                       rc = true;
+                       break;
+               }
+       }
+
+       /* verify received frame length and contents */
+       if (rc &&
+           ( info->tmp_rx_buf_count != count ||
+             memcmp(buf, info->tmp_rx_buf,count))) {
+               rc = false;
+       }
+
+       spin_lock_irqsave(&info->lock,flags);
+       reset_adapter(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       info->params.clock_speed = speed;
+       info->port.tty = oldtty;
+
+       return rc;
+}
+
+/* Perform diagnostics on hardware
+ */
+static int adapter_test( SLMP_INFO *info )
+{
+       unsigned long flags;
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk( "%s(%d):Testing device %s\n",
+                       __FILE__,__LINE__,info->device_name );
+
+       spin_lock_irqsave(&info->lock,flags);
+       init_adapter(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       info->port_array[0]->port_count = 0;
+
+       if ( register_test(info->port_array[0]) &&
+               register_test(info->port_array[1])) {
+
+               info->port_array[0]->port_count = 2;
+
+               if ( register_test(info->port_array[2]) &&
+                       register_test(info->port_array[3]) )
+                       info->port_array[0]->port_count += 2;
+       }
+       else {
+               printk( "%s(%d):Register test failure for device %s Addr=%08lX\n",
+                       __FILE__,__LINE__,info->device_name, (unsigned long)(info->phys_sca_base));
+               return -ENODEV;
+       }
+
+       if ( !irq_test(info->port_array[0]) ||
+               !irq_test(info->port_array[1]) ||
+                (info->port_count == 4 && !irq_test(info->port_array[2])) ||
+                (info->port_count == 4 && !irq_test(info->port_array[3]))) {
+               printk( "%s(%d):Interrupt test failure for device %s IRQ=%d\n",
+                       __FILE__,__LINE__,info->device_name, (unsigned short)(info->irq_level) );
+               return -ENODEV;
+       }
+
+       if (!loopback_test(info->port_array[0]) ||
+               !loopback_test(info->port_array[1]) ||
+                (info->port_count == 4 && !loopback_test(info->port_array[2])) ||
+                (info->port_count == 4 && !loopback_test(info->port_array[3]))) {
+               printk( "%s(%d):DMA test failure for device %s\n",
+                       __FILE__,__LINE__,info->device_name);
+               return -ENODEV;
+       }
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk( "%s(%d):device %s passed diagnostics\n",
+                       __FILE__,__LINE__,info->device_name );
+
+       info->port_array[0]->init_error = 0;
+       info->port_array[1]->init_error = 0;
+       if ( info->port_count > 2 ) {
+               info->port_array[2]->init_error = 0;
+               info->port_array[3]->init_error = 0;
+       }
+
+       return 0;
+}
+
+/* Test the shared memory on a PCI adapter.
+ */
+static bool memory_test(SLMP_INFO *info)
+{
+       static unsigned long testval[] = { 0x0, 0x55555555, 0xaaaaaaaa,
+               0x66666666, 0x99999999, 0xffffffff, 0x12345678 };
+       unsigned long count = ARRAY_SIZE(testval);
+       unsigned long i;
+       unsigned long limit = SCA_MEM_SIZE/sizeof(unsigned long);
+       unsigned long * addr = (unsigned long *)info->memory_base;
+
+       /* Test data lines with test pattern at one location. */
+
+       for ( i = 0 ; i < count ; i++ ) {
+               *addr = testval[i];
+               if ( *addr != testval[i] )
+                       return false;
+       }
+
+       /* Test address lines with incrementing pattern over */
+       /* entire address range. */
+
+       for ( i = 0 ; i < limit ; i++ ) {
+               *addr = i * 4;
+               addr++;
+       }
+
+       addr = (unsigned long *)info->memory_base;
+
+       for ( i = 0 ; i < limit ; i++ ) {
+               if ( *addr != i * 4 )
+                       return false;
+               addr++;
+       }
+
+       memset( info->memory_base, 0, SCA_MEM_SIZE );
+       return true;
+}
+
+/* Load data into PCI adapter shared memory.
+ *
+ * The PCI9050 releases control of the local bus
+ * after completing the current read or write operation.
+ *
+ * While the PCI9050 write FIFO not empty, the
+ * PCI9050 treats all of the writes as a single transaction
+ * and does not release the bus. This causes DMA latency problems
+ * at high speeds when copying large data blocks to the shared memory.
+ *
+ * This function breaks a write into multiple transations by
+ * interleaving a read which flushes the write FIFO and 'completes'
+ * the write transation. This allows any pending DMA request to gain control
+ * of the local bus in a timely fasion.
+ */
+static void load_pci_memory(SLMP_INFO *info, char* dest, const char* src, unsigned short count)
+{
+       /* A load interval of 16 allows for 4 32-bit writes at */
+       /* 136ns each for a maximum latency of 542ns on the local bus.*/
+
+       unsigned short interval = count / sca_pci_load_interval;
+       unsigned short i;
+
+       for ( i = 0 ; i < interval ; i++ )
+       {
+               memcpy(dest, src, sca_pci_load_interval);
+               read_status_reg(info);
+               dest += sca_pci_load_interval;
+               src += sca_pci_load_interval;
+       }
+
+       memcpy(dest, src, count % sca_pci_load_interval);
+}
+
+static void trace_block(SLMP_INFO *info,const char* data, int count, int xmit)
+{
+       int i;
+       int linecount;
+       if (xmit)
+               printk("%s tx data:\n",info->device_name);
+       else
+               printk("%s rx data:\n",info->device_name);
+
+       while(count) {
+               if (count > 16)
+                       linecount = 16;
+               else
+                       linecount = count;
+
+               for(i=0;i<linecount;i++)
+                       printk("%02X ",(unsigned char)data[i]);
+               for(;i<17;i++)
+                       printk("   ");
+               for(i=0;i<linecount;i++) {
+                       if (data[i]>=040 && data[i]<=0176)
+                               printk("%c",data[i]);
+                       else
+                               printk(".");
+               }
+               printk("\n");
+
+               data  += linecount;
+               count -= linecount;
+       }
+}      /* end of trace_block() */
+
+/* called when HDLC frame times out
+ * update stats and do tx completion processing
+ */
+static void tx_timeout(unsigned long context)
+{
+       SLMP_INFO *info = (SLMP_INFO*)context;
+       unsigned long flags;
+
+       if ( debug_level >= DEBUG_LEVEL_INFO )
+               printk( "%s(%d):%s tx_timeout()\n",
+                       __FILE__,__LINE__,info->device_name);
+       if(info->tx_active && info->params.mode == MGSL_MODE_HDLC) {
+               info->icount.txtimeout++;
+       }
+       spin_lock_irqsave(&info->lock,flags);
+       info->tx_active = false;
+       info->tx_count = info->tx_put = info->tx_get = 0;
+
+       spin_unlock_irqrestore(&info->lock,flags);
+
+#if SYNCLINK_GENERIC_HDLC
+       if (info->netcount)
+               hdlcdev_tx_done(info);
+       else
+#endif
+               bh_transmit(info);
+}
+
+/* called to periodically check the DSR/RI modem signal input status
+ */
+static void status_timeout(unsigned long context)
+{
+       u16 status = 0;
+       SLMP_INFO *info = (SLMP_INFO*)context;
+       unsigned long flags;
+       unsigned char delta;
+
+
+       spin_lock_irqsave(&info->lock,flags);
+       get_signals(info);
+       spin_unlock_irqrestore(&info->lock,flags);
+
+       /* check for DSR/RI state change */
+
+       delta = info->old_signals ^ info->serial_signals;
+       info->old_signals = info->serial_signals;
+
+       if (delta & SerialSignal_DSR)
+               status |= MISCSTATUS_DSR_LATCHED|(info->serial_signals&SerialSignal_DSR);
+
+       if (delta & SerialSignal_RI)
+               status |= MISCSTATUS_RI_LATCHED|(info->serial_signals&SerialSignal_RI);
+
+       if (delta & SerialSignal_DCD)
+               status |= MISCSTATUS_DCD_LATCHED|(info->serial_signals&SerialSignal_DCD);
+
+       if (delta & SerialSignal_CTS)
+               status |= MISCSTATUS_CTS_LATCHED|(info->serial_signals&SerialSignal_CTS);
+
+       if (status)
+               isr_io_pin(info,status);
+
+       mod_timer(&info->status_timer, jiffies + msecs_to_jiffies(10));
+}
+
+
+/* Register Access Routines -
+ * All registers are memory mapped
+ */
+#define CALC_REGADDR() \
+       unsigned char * RegAddr = (unsigned char*)(info->sca_base + Addr); \
+       if (info->port_num > 1) \
+               RegAddr += 256;                 /* port 0-1 SCA0, 2-3 SCA1 */ \
+       if ( info->port_num & 1) { \
+               if (Addr > 0x7f) \
+                       RegAddr += 0x40;        /* DMA access */ \
+               else if (Addr > 0x1f && Addr < 0x60) \
+                       RegAddr += 0x20;        /* MSCI access */ \
+       }
+
+
+static unsigned char read_reg(SLMP_INFO * info, unsigned char Addr)
+{
+       CALC_REGADDR();
+       return *RegAddr;
+}
+static void write_reg(SLMP_INFO * info, unsigned char Addr, unsigned char Value)
+{
+       CALC_REGADDR();
+       *RegAddr = Value;
+}
+
+static u16 read_reg16(SLMP_INFO * info, unsigned char Addr)
+{
+       CALC_REGADDR();
+       return *((u16 *)RegAddr);
+}
+
+static void write_reg16(SLMP_INFO * info, unsigned char Addr, u16 Value)
+{
+       CALC_REGADDR();
+       *((u16 *)RegAddr) = Value;
+}
+
+static unsigned char read_status_reg(SLMP_INFO * info)
+{
+       unsigned char *RegAddr = (unsigned char *)info->statctrl_base;
+       return *RegAddr;
+}
+
+static void write_control_reg(SLMP_INFO * info)
+{
+       unsigned char *RegAddr = (unsigned char *)info->statctrl_base;
+       *RegAddr = info->port_array[0]->ctrlreg_value;
+}
+
+
+static int synclinkmp_init_one (struct pci_dev *dev,
+                                         const struct pci_device_id *ent)
+{
+       if (pci_enable_device(dev)) {
+               printk("error enabling pci device %p\n", dev);
+               return -EIO;
+       }
+       device_init( ++synclinkmp_adapter_count, dev );
+       return 0;
+}
+
+static void synclinkmp_remove_one (struct pci_dev *dev)
+{
+}