Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / tty / serial / sunsab.c
diff --git a/kernel/drivers/tty/serial/sunsab.c b/kernel/drivers/tty/serial/sunsab.c
new file mode 100644 (file)
index 0000000..b5e3195
--- /dev/null
@@ -0,0 +1,1160 @@
+/* sunsab.c: ASYNC Driver for the SIEMENS SAB82532 DUSCC.
+ *
+ * Copyright (C) 1997  Eddie C. Dost  (ecd@skynet.be)
+ * Copyright (C) 2002, 2006  David S. Miller (davem@davemloft.net)
+ *
+ * Rewrote buffer handling to use CIRC(Circular Buffer) macros.
+ *   Maxim Krasnyanskiy <maxk@qualcomm.com>
+ *
+ * Fixed to use tty_get_baud_rate, and to allow for arbitrary baud
+ * rates to be programmed into the UART.  Also eliminated a lot of
+ * duplicated code in the console setup.
+ *   Theodore Ts'o <tytso@mit.edu>, 2001-Oct-12
+ *
+ * Ported to new 2.5.x UART layer.
+ *   David S. Miller <davem@davemloft.net>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/major.h>
+#include <linux/string.h>
+#include <linux/ptrace.h>
+#include <linux/ioport.h>
+#include <linux/circ_buf.h>
+#include <linux/serial.h>
+#include <linux/sysrq.h>
+#include <linux/console.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/of_device.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/prom.h>
+#include <asm/setup.h>
+
+#if defined(CONFIG_SERIAL_SUNSAB_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/serial_core.h>
+#include <linux/sunserialcore.h>
+
+#include "sunsab.h"
+
+struct uart_sunsab_port {
+       struct uart_port                port;           /* Generic UART port    */
+       union sab82532_async_regs       __iomem *regs;  /* Chip registers       */
+       unsigned long                   irqflags;       /* IRQ state flags      */
+       int                             dsr;            /* Current DSR state    */
+       unsigned int                    cec_timeout;    /* Chip poll timeout... */
+       unsigned int                    tec_timeout;    /* likewise             */
+       unsigned char                   interrupt_mask0;/* ISR0 masking         */
+       unsigned char                   interrupt_mask1;/* ISR1 masking         */
+       unsigned char                   pvr_dtr_bit;    /* Which PVR bit is DTR */
+       unsigned char                   pvr_dsr_bit;    /* Which PVR bit is DSR */
+       unsigned int                    gis_shift;
+       int                             type;           /* SAB82532 version     */
+
+       /* Setting configuration bits while the transmitter is active
+        * can cause garbage characters to get emitted by the chip.
+        * Therefore, we cache such writes here and do the real register
+        * write the next time the transmitter becomes idle.
+        */
+       unsigned int                    cached_ebrg;
+       unsigned char                   cached_mode;
+       unsigned char                   cached_pvr;
+       unsigned char                   cached_dafo;
+};
+
+/*
+ * This assumes you have a 29.4912 MHz clock for your UART.
+ */
+#define SAB_BASE_BAUD ( 29491200 / 16 )
+
+static char *sab82532_version[16] = {
+       "V1.0", "V2.0", "V3.2", "V(0x03)",
+       "V(0x04)", "V(0x05)", "V(0x06)", "V(0x07)",
+       "V(0x08)", "V(0x09)", "V(0x0a)", "V(0x0b)",
+       "V(0x0c)", "V(0x0d)", "V(0x0e)", "V(0x0f)"
+};
+
+#define SAB82532_MAX_TEC_TIMEOUT 200000        /* 1 character time (at 50 baud) */
+#define SAB82532_MAX_CEC_TIMEOUT  50000        /* 2.5 TX CLKs (at 50 baud) */
+
+#define SAB82532_RECV_FIFO_SIZE        32      /* Standard async fifo sizes */
+#define SAB82532_XMIT_FIFO_SIZE        32
+
+static __inline__ void sunsab_tec_wait(struct uart_sunsab_port *up)
+{
+       int timeout = up->tec_timeout;
+
+       while ((readb(&up->regs->r.star) & SAB82532_STAR_TEC) && --timeout)
+               udelay(1);
+}
+
+static __inline__ void sunsab_cec_wait(struct uart_sunsab_port *up)
+{
+       int timeout = up->cec_timeout;
+
+       while ((readb(&up->regs->r.star) & SAB82532_STAR_CEC) && --timeout)
+               udelay(1);
+}
+
+static struct tty_port *
+receive_chars(struct uart_sunsab_port *up,
+             union sab82532_irq_status *stat)
+{
+       struct tty_port *port = NULL;
+       unsigned char buf[32];
+       int saw_console_brk = 0;
+       int free_fifo = 0;
+       int count = 0;
+       int i;
+
+       if (up->port.state != NULL)             /* Unopened serial console */
+               port = &up->port.state->port;
+
+       /* Read number of BYTES (Character + Status) available. */
+       if (stat->sreg.isr0 & SAB82532_ISR0_RPF) {
+               count = SAB82532_RECV_FIFO_SIZE;
+               free_fifo++;
+       }
+
+       if (stat->sreg.isr0 & SAB82532_ISR0_TCD) {
+               count = readb(&up->regs->r.rbcl) & (SAB82532_RECV_FIFO_SIZE - 1);
+               free_fifo++;
+       }
+
+       /* Issue a FIFO read command in case we where idle. */
+       if (stat->sreg.isr0 & SAB82532_ISR0_TIME) {
+               sunsab_cec_wait(up);
+               writeb(SAB82532_CMDR_RFRD, &up->regs->w.cmdr);
+               return port;
+       }
+
+       if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
+               free_fifo++;
+
+       /* Read the FIFO. */
+       for (i = 0; i < count; i++)
+               buf[i] = readb(&up->regs->r.rfifo[i]);
+
+       /* Issue Receive Message Complete command. */
+       if (free_fifo) {
+               sunsab_cec_wait(up);
+               writeb(SAB82532_CMDR_RMC, &up->regs->w.cmdr);
+       }
+
+       /* Count may be zero for BRK, so we check for it here */
+       if ((stat->sreg.isr1 & SAB82532_ISR1_BRK) &&
+           (up->port.line == up->port.cons->index))
+               saw_console_brk = 1;
+
+       if (count == 0) {
+               if (unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
+                       stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
+                                            SAB82532_ISR0_FERR);
+                       up->port.icount.brk++;
+                       uart_handle_break(&up->port);
+               }
+       }
+
+       for (i = 0; i < count; i++) {
+               unsigned char ch = buf[i], flag;
+
+               flag = TTY_NORMAL;
+               up->port.icount.rx++;
+
+               if (unlikely(stat->sreg.isr0 & (SAB82532_ISR0_PERR |
+                                               SAB82532_ISR0_FERR |
+                                               SAB82532_ISR0_RFO)) ||
+                   unlikely(stat->sreg.isr1 & SAB82532_ISR1_BRK)) {
+                       /*
+                        * For statistics only
+                        */
+                       if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
+                               stat->sreg.isr0 &= ~(SAB82532_ISR0_PERR |
+                                                    SAB82532_ISR0_FERR);
+                               up->port.icount.brk++;
+                               /*
+                                * We do the SysRQ and SAK checking
+                                * here because otherwise the break
+                                * may get masked by ignore_status_mask
+                                * or read_status_mask.
+                                */
+                               if (uart_handle_break(&up->port))
+                                       continue;
+                       } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
+                               up->port.icount.parity++;
+                       else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
+                               up->port.icount.frame++;
+                       if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
+                               up->port.icount.overrun++;
+
+                       /*
+                        * Mask off conditions which should be ingored.
+                        */
+                       stat->sreg.isr0 &= (up->port.read_status_mask & 0xff);
+                       stat->sreg.isr1 &= ((up->port.read_status_mask >> 8) & 0xff);
+
+                       if (stat->sreg.isr1 & SAB82532_ISR1_BRK) {
+                               flag = TTY_BREAK;
+                       } else if (stat->sreg.isr0 & SAB82532_ISR0_PERR)
+                               flag = TTY_PARITY;
+                       else if (stat->sreg.isr0 & SAB82532_ISR0_FERR)
+                               flag = TTY_FRAME;
+               }
+
+               if (uart_handle_sysrq_char(&up->port, ch) || !port)
+                       continue;
+
+               if ((stat->sreg.isr0 & (up->port.ignore_status_mask & 0xff)) == 0 &&
+                   (stat->sreg.isr1 & ((up->port.ignore_status_mask >> 8) & 0xff)) == 0)
+                       tty_insert_flip_char(port, ch, flag);
+               if (stat->sreg.isr0 & SAB82532_ISR0_RFO)
+                       tty_insert_flip_char(port, 0, TTY_OVERRUN);
+       }
+
+       if (saw_console_brk)
+               sun_do_break();
+
+       return port;
+}
+
+static void sunsab_stop_tx(struct uart_port *);
+static void sunsab_tx_idle(struct uart_sunsab_port *);
+
+static void transmit_chars(struct uart_sunsab_port *up,
+                          union sab82532_irq_status *stat)
+{
+       struct circ_buf *xmit = &up->port.state->xmit;
+       int i;
+
+       if (stat->sreg.isr1 & SAB82532_ISR1_ALLS) {
+               up->interrupt_mask1 |= SAB82532_IMR1_ALLS;
+               writeb(up->interrupt_mask1, &up->regs->w.imr1);
+               set_bit(SAB82532_ALLS, &up->irqflags);
+       }
+
+#if 0 /* bde@nwlink.com says this check causes problems */
+       if (!(stat->sreg.isr1 & SAB82532_ISR1_XPR))
+               return;
+#endif
+
+       if (!(readb(&up->regs->r.star) & SAB82532_STAR_XFW))
+               return;
+
+       set_bit(SAB82532_XPR, &up->irqflags);
+       sunsab_tx_idle(up);
+
+       if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
+               up->interrupt_mask1 |= SAB82532_IMR1_XPR;
+               writeb(up->interrupt_mask1, &up->regs->w.imr1);
+               return;
+       }
+
+       up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
+       writeb(up->interrupt_mask1, &up->regs->w.imr1);
+       clear_bit(SAB82532_ALLS, &up->irqflags);
+
+       /* Stuff 32 bytes into Transmit FIFO. */
+       clear_bit(SAB82532_XPR, &up->irqflags);
+       for (i = 0; i < up->port.fifosize; i++) {
+               writeb(xmit->buf[xmit->tail],
+                      &up->regs->w.xfifo[i]);
+               xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+               up->port.icount.tx++;
+               if (uart_circ_empty(xmit))
+                       break;
+       }
+
+       /* Issue a Transmit Frame command. */
+       sunsab_cec_wait(up);
+       writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
+
+       if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+               uart_write_wakeup(&up->port);
+
+       if (uart_circ_empty(xmit))
+               sunsab_stop_tx(&up->port);
+}
+
+static void check_status(struct uart_sunsab_port *up,
+                        union sab82532_irq_status *stat)
+{
+       if (stat->sreg.isr0 & SAB82532_ISR0_CDSC)
+               uart_handle_dcd_change(&up->port,
+                                      !(readb(&up->regs->r.vstr) & SAB82532_VSTR_CD));
+
+       if (stat->sreg.isr1 & SAB82532_ISR1_CSC)
+               uart_handle_cts_change(&up->port,
+                                      (readb(&up->regs->r.star) & SAB82532_STAR_CTS));
+
+       if ((readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ^ up->dsr) {
+               up->dsr = (readb(&up->regs->r.pvr) & up->pvr_dsr_bit) ? 0 : 1;
+               up->port.icount.dsr++;
+       }
+
+       wake_up_interruptible(&up->port.state->port.delta_msr_wait);
+}
+
+static irqreturn_t sunsab_interrupt(int irq, void *dev_id)
+{
+       struct uart_sunsab_port *up = dev_id;
+       struct tty_port *port = NULL;
+       union sab82532_irq_status status;
+       unsigned long flags;
+       unsigned char gis;
+
+       spin_lock_irqsave(&up->port.lock, flags);
+
+       status.stat = 0;
+       gis = readb(&up->regs->r.gis) >> up->gis_shift;
+       if (gis & 1)
+               status.sreg.isr0 = readb(&up->regs->r.isr0);
+       if (gis & 2)
+               status.sreg.isr1 = readb(&up->regs->r.isr1);
+
+       if (status.stat) {
+               if ((status.sreg.isr0 & (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
+                                        SAB82532_ISR0_RFO | SAB82532_ISR0_RPF)) ||
+                   (status.sreg.isr1 & SAB82532_ISR1_BRK))
+                       port = receive_chars(up, &status);
+               if ((status.sreg.isr0 & SAB82532_ISR0_CDSC) ||
+                   (status.sreg.isr1 & SAB82532_ISR1_CSC))
+                       check_status(up, &status);
+               if (status.sreg.isr1 & (SAB82532_ISR1_ALLS | SAB82532_ISR1_XPR))
+                       transmit_chars(up, &status);
+       }
+
+       spin_unlock_irqrestore(&up->port.lock, flags);
+
+       if (port)
+               tty_flip_buffer_push(port);
+
+       return IRQ_HANDLED;
+}
+
+/* port->lock is not held.  */
+static unsigned int sunsab_tx_empty(struct uart_port *port)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       int ret;
+
+       /* Do not need a lock for a state test like this.  */
+       if (test_bit(SAB82532_ALLS, &up->irqflags))
+               ret = TIOCSER_TEMT;
+       else
+               ret = 0;
+
+       return ret;
+}
+
+/* port->lock held by caller.  */
+static void sunsab_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+
+       if (mctrl & TIOCM_RTS) {
+               up->cached_mode &= ~SAB82532_MODE_FRTS;
+               up->cached_mode |= SAB82532_MODE_RTS;
+       } else {
+               up->cached_mode |= (SAB82532_MODE_FRTS |
+                                   SAB82532_MODE_RTS);
+       }
+       if (mctrl & TIOCM_DTR) {
+               up->cached_pvr &= ~(up->pvr_dtr_bit);
+       } else {
+               up->cached_pvr |= up->pvr_dtr_bit;
+       }
+
+       set_bit(SAB82532_REGS_PENDING, &up->irqflags);
+       if (test_bit(SAB82532_XPR, &up->irqflags))
+               sunsab_tx_idle(up);
+}
+
+/* port->lock is held by caller and interrupts are disabled.  */
+static unsigned int sunsab_get_mctrl(struct uart_port *port)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       unsigned char val;
+       unsigned int result;
+
+       result = 0;
+
+       val = readb(&up->regs->r.pvr);
+       result |= (val & up->pvr_dsr_bit) ? 0 : TIOCM_DSR;
+
+       val = readb(&up->regs->r.vstr);
+       result |= (val & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR;
+
+       val = readb(&up->regs->r.star);
+       result |= (val & SAB82532_STAR_CTS) ? TIOCM_CTS : 0;
+
+       return result;
+}
+
+/* port->lock held by caller.  */
+static void sunsab_stop_tx(struct uart_port *port)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+
+       up->interrupt_mask1 |= SAB82532_IMR1_XPR;
+       writeb(up->interrupt_mask1, &up->regs->w.imr1);
+}
+
+/* port->lock held by caller.  */
+static void sunsab_tx_idle(struct uart_sunsab_port *up)
+{
+       if (test_bit(SAB82532_REGS_PENDING, &up->irqflags)) {
+               u8 tmp;
+
+               clear_bit(SAB82532_REGS_PENDING, &up->irqflags);
+               writeb(up->cached_mode, &up->regs->rw.mode);
+               writeb(up->cached_pvr, &up->regs->rw.pvr);
+               writeb(up->cached_dafo, &up->regs->w.dafo);
+
+               writeb(up->cached_ebrg & 0xff, &up->regs->w.bgr);
+               tmp = readb(&up->regs->rw.ccr2);
+               tmp &= ~0xc0;
+               tmp |= (up->cached_ebrg >> 2) & 0xc0;
+               writeb(tmp, &up->regs->rw.ccr2);
+       }
+}
+
+/* port->lock held by caller.  */
+static void sunsab_start_tx(struct uart_port *port)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       struct circ_buf *xmit = &up->port.state->xmit;
+       int i;
+
+       if (uart_circ_empty(xmit) || uart_tx_stopped(port))
+               return;
+
+       up->interrupt_mask1 &= ~(SAB82532_IMR1_ALLS|SAB82532_IMR1_XPR);
+       writeb(up->interrupt_mask1, &up->regs->w.imr1);
+       
+       if (!test_bit(SAB82532_XPR, &up->irqflags))
+               return;
+
+       clear_bit(SAB82532_ALLS, &up->irqflags);
+       clear_bit(SAB82532_XPR, &up->irqflags);
+
+       for (i = 0; i < up->port.fifosize; i++) {
+               writeb(xmit->buf[xmit->tail],
+                      &up->regs->w.xfifo[i]);
+               xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+               up->port.icount.tx++;
+               if (uart_circ_empty(xmit))
+                       break;
+       }
+
+       /* Issue a Transmit Frame command.  */
+       sunsab_cec_wait(up);
+       writeb(SAB82532_CMDR_XF, &up->regs->w.cmdr);
+}
+
+/* port->lock is not held.  */
+static void sunsab_send_xchar(struct uart_port *port, char ch)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       unsigned long flags;
+
+       if (ch == __DISABLED_CHAR)
+               return;
+
+       spin_lock_irqsave(&up->port.lock, flags);
+
+       sunsab_tec_wait(up);
+       writeb(ch, &up->regs->w.tic);
+
+       spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+/* port->lock held by caller.  */
+static void sunsab_stop_rx(struct uart_port *port)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+
+       up->interrupt_mask0 |= SAB82532_IMR0_TCD;
+       writeb(up->interrupt_mask1, &up->regs->w.imr0);
+}
+
+/* port->lock is not held.  */
+static void sunsab_break_ctl(struct uart_port *port, int break_state)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       unsigned long flags;
+       unsigned char val;
+
+       spin_lock_irqsave(&up->port.lock, flags);
+
+       val = up->cached_dafo;
+       if (break_state)
+               val |= SAB82532_DAFO_XBRK;
+       else
+               val &= ~SAB82532_DAFO_XBRK;
+       up->cached_dafo = val;
+
+       set_bit(SAB82532_REGS_PENDING, &up->irqflags);
+       if (test_bit(SAB82532_XPR, &up->irqflags))
+               sunsab_tx_idle(up);
+
+       spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+/* port->lock is not held.  */
+static int sunsab_startup(struct uart_port *port)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       unsigned long flags;
+       unsigned char tmp;
+       int err = request_irq(up->port.irq, sunsab_interrupt,
+                             IRQF_SHARED, "sab", up);
+       if (err)
+               return err;
+
+       spin_lock_irqsave(&up->port.lock, flags);
+
+       /*
+        * Wait for any commands or immediate characters
+        */
+       sunsab_cec_wait(up);
+       sunsab_tec_wait(up);
+
+       /*
+        * Clear the FIFO buffers.
+        */
+       writeb(SAB82532_CMDR_RRES, &up->regs->w.cmdr);
+       sunsab_cec_wait(up);
+       writeb(SAB82532_CMDR_XRES, &up->regs->w.cmdr);
+
+       /*
+        * Clear the interrupt registers.
+        */
+       (void) readb(&up->regs->r.isr0);
+       (void) readb(&up->regs->r.isr1);
+
+       /*
+        * Now, initialize the UART 
+        */
+       writeb(0, &up->regs->w.ccr0);                           /* power-down */
+       writeb(SAB82532_CCR0_MCE | SAB82532_CCR0_SC_NRZ |
+              SAB82532_CCR0_SM_ASYNC, &up->regs->w.ccr0);
+       writeb(SAB82532_CCR1_ODS | SAB82532_CCR1_BCR | 7, &up->regs->w.ccr1);
+       writeb(SAB82532_CCR2_BDF | SAB82532_CCR2_SSEL |
+              SAB82532_CCR2_TOE, &up->regs->w.ccr2);
+       writeb(0, &up->regs->w.ccr3);
+       writeb(SAB82532_CCR4_MCK4 | SAB82532_CCR4_EBRG, &up->regs->w.ccr4);
+       up->cached_mode = (SAB82532_MODE_RTS | SAB82532_MODE_FCTS |
+                          SAB82532_MODE_RAC);
+       writeb(up->cached_mode, &up->regs->w.mode);
+       writeb(SAB82532_RFC_DPS|SAB82532_RFC_RFTH_32, &up->regs->w.rfc);
+       
+       tmp = readb(&up->regs->rw.ccr0);
+       tmp |= SAB82532_CCR0_PU;        /* power-up */
+       writeb(tmp, &up->regs->rw.ccr0);
+
+       /*
+        * Finally, enable interrupts
+        */
+       up->interrupt_mask0 = (SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
+                              SAB82532_IMR0_PLLA);
+       writeb(up->interrupt_mask0, &up->regs->w.imr0);
+       up->interrupt_mask1 = (SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
+                              SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
+                              SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
+                              SAB82532_IMR1_XPR);
+       writeb(up->interrupt_mask1, &up->regs->w.imr1);
+       set_bit(SAB82532_ALLS, &up->irqflags);
+       set_bit(SAB82532_XPR, &up->irqflags);
+
+       spin_unlock_irqrestore(&up->port.lock, flags);
+
+       return 0;
+}
+
+/* port->lock is not held.  */
+static void sunsab_shutdown(struct uart_port *port)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       unsigned long flags;
+
+       spin_lock_irqsave(&up->port.lock, flags);
+
+       /* Disable Interrupts */
+       up->interrupt_mask0 = 0xff;
+       writeb(up->interrupt_mask0, &up->regs->w.imr0);
+       up->interrupt_mask1 = 0xff;
+       writeb(up->interrupt_mask1, &up->regs->w.imr1);
+
+       /* Disable break condition */
+       up->cached_dafo = readb(&up->regs->rw.dafo);
+       up->cached_dafo &= ~SAB82532_DAFO_XBRK;
+       writeb(up->cached_dafo, &up->regs->rw.dafo);
+
+       /* Disable Receiver */  
+       up->cached_mode &= ~SAB82532_MODE_RAC;
+       writeb(up->cached_mode, &up->regs->rw.mode);
+
+       /*
+        * XXX FIXME
+        *
+        * If the chip is powered down here the system hangs/crashes during
+        * reboot or shutdown.  This needs to be investigated further,
+        * similar behaviour occurs in 2.4 when the driver is configured
+        * as a module only.  One hint may be that data is sometimes
+        * transmitted at 9600 baud during shutdown (regardless of the
+        * speed the chip was configured for when the port was open).
+        */
+#if 0
+       /* Power Down */        
+       tmp = readb(&up->regs->rw.ccr0);
+       tmp &= ~SAB82532_CCR0_PU;
+       writeb(tmp, &up->regs->rw.ccr0);
+#endif
+
+       spin_unlock_irqrestore(&up->port.lock, flags);
+       free_irq(up->port.irq, up);
+}
+
+/*
+ * This is used to figure out the divisor speeds.
+ *
+ * The formula is:    Baud = SAB_BASE_BAUD / ((N + 1) * (1 << M)),
+ *
+ * with               0 <= N < 64 and 0 <= M < 16
+ */
+
+static void calc_ebrg(int baud, int *n_ret, int *m_ret)
+{
+       int     n, m;
+
+       if (baud == 0) {
+               *n_ret = 0;
+               *m_ret = 0;
+               return;
+       }
+     
+       /*
+        * We scale numbers by 10 so that we get better accuracy
+        * without having to use floating point.  Here we increment m
+        * until n is within the valid range.
+        */
+       n = (SAB_BASE_BAUD * 10) / baud;
+       m = 0;
+       while (n >= 640) {
+               n = n / 2;
+               m++;
+       }
+       n = (n+5) / 10;
+       /*
+        * We try very hard to avoid speeds with M == 0 since they may
+        * not work correctly for XTAL frequences above 10 MHz.
+        */
+       if ((m == 0) && ((n & 1) == 0)) {
+               n = n / 2;
+               m++;
+       }
+       *n_ret = n - 1;
+       *m_ret = m;
+}
+
+/* Internal routine, port->lock is held and local interrupts are disabled.  */
+static void sunsab_convert_to_sab(struct uart_sunsab_port *up, unsigned int cflag,
+                                 unsigned int iflag, unsigned int baud,
+                                 unsigned int quot)
+{
+       unsigned char dafo;
+       int bits, n, m;
+
+       /* Byte size and parity */
+       switch (cflag & CSIZE) {
+             case CS5: dafo = SAB82532_DAFO_CHL5; bits = 7; break;
+             case CS6: dafo = SAB82532_DAFO_CHL6; bits = 8; break;
+             case CS7: dafo = SAB82532_DAFO_CHL7; bits = 9; break;
+             case CS8: dafo = SAB82532_DAFO_CHL8; bits = 10; break;
+             /* Never happens, but GCC is too dumb to figure it out */
+             default:  dafo = SAB82532_DAFO_CHL5; bits = 7; break;
+       }
+
+       if (cflag & CSTOPB) {
+               dafo |= SAB82532_DAFO_STOP;
+               bits++;
+       }
+
+       if (cflag & PARENB) {
+               dafo |= SAB82532_DAFO_PARE;
+               bits++;
+       }
+
+       if (cflag & PARODD) {
+               dafo |= SAB82532_DAFO_PAR_ODD;
+       } else {
+               dafo |= SAB82532_DAFO_PAR_EVEN;
+       }
+       up->cached_dafo = dafo;
+
+       calc_ebrg(baud, &n, &m);
+
+       up->cached_ebrg = n | (m << 6);
+
+       up->tec_timeout = (10 * 1000000) / baud;
+       up->cec_timeout = up->tec_timeout >> 2;
+
+       /* CTS flow control flags */
+       /* We encode read_status_mask and ignore_status_mask like so:
+        *
+        * ---------------------
+        * | ... | ISR1 | ISR0 |
+        * ---------------------
+        *  ..    15   8 7    0
+        */
+
+       up->port.read_status_mask = (SAB82532_ISR0_TCD | SAB82532_ISR0_TIME |
+                                    SAB82532_ISR0_RFO | SAB82532_ISR0_RPF |
+                                    SAB82532_ISR0_CDSC);
+       up->port.read_status_mask |= (SAB82532_ISR1_CSC |
+                                     SAB82532_ISR1_ALLS |
+                                     SAB82532_ISR1_XPR) << 8;
+       if (iflag & INPCK)
+               up->port.read_status_mask |= (SAB82532_ISR0_PERR |
+                                             SAB82532_ISR0_FERR);
+       if (iflag & (IGNBRK | BRKINT | PARMRK))
+               up->port.read_status_mask |= (SAB82532_ISR1_BRK << 8);
+
+       /*
+        * Characteres to ignore
+        */
+       up->port.ignore_status_mask = 0;
+       if (iflag & IGNPAR)
+               up->port.ignore_status_mask |= (SAB82532_ISR0_PERR |
+                                               SAB82532_ISR0_FERR);
+       if (iflag & IGNBRK) {
+               up->port.ignore_status_mask |= (SAB82532_ISR1_BRK << 8);
+               /*
+                * If we're ignoring parity and break indicators,
+                * ignore overruns too (for real raw support).
+                */
+               if (iflag & IGNPAR)
+                       up->port.ignore_status_mask |= SAB82532_ISR0_RFO;
+       }
+
+       /*
+        * ignore all characters if CREAD is not set
+        */
+       if ((cflag & CREAD) == 0)
+               up->port.ignore_status_mask |= (SAB82532_ISR0_RPF |
+                                               SAB82532_ISR0_TCD);
+
+       uart_update_timeout(&up->port, cflag,
+                           (up->port.uartclk / (16 * quot)));
+
+       /* Now schedule a register update when the chip's
+        * transmitter is idle.
+        */
+       up->cached_mode |= SAB82532_MODE_RAC;
+       set_bit(SAB82532_REGS_PENDING, &up->irqflags);
+       if (test_bit(SAB82532_XPR, &up->irqflags))
+               sunsab_tx_idle(up);
+}
+
+/* port->lock is not held.  */
+static void sunsab_set_termios(struct uart_port *port, struct ktermios *termios,
+                              struct ktermios *old)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+       unsigned long flags;
+       unsigned int baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
+       unsigned int quot = uart_get_divisor(port, baud);
+
+       spin_lock_irqsave(&up->port.lock, flags);
+       sunsab_convert_to_sab(up, termios->c_cflag, termios->c_iflag, baud, quot);
+       spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static const char *sunsab_type(struct uart_port *port)
+{
+       struct uart_sunsab_port *up = (void *)port;
+       static char buf[36];
+       
+       sprintf(buf, "SAB82532 %s", sab82532_version[up->type]);
+       return buf;
+}
+
+static void sunsab_release_port(struct uart_port *port)
+{
+}
+
+static int sunsab_request_port(struct uart_port *port)
+{
+       return 0;
+}
+
+static void sunsab_config_port(struct uart_port *port, int flags)
+{
+}
+
+static int sunsab_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+       return -EINVAL;
+}
+
+static struct uart_ops sunsab_pops = {
+       .tx_empty       = sunsab_tx_empty,
+       .set_mctrl      = sunsab_set_mctrl,
+       .get_mctrl      = sunsab_get_mctrl,
+       .stop_tx        = sunsab_stop_tx,
+       .start_tx       = sunsab_start_tx,
+       .send_xchar     = sunsab_send_xchar,
+       .stop_rx        = sunsab_stop_rx,
+       .break_ctl      = sunsab_break_ctl,
+       .startup        = sunsab_startup,
+       .shutdown       = sunsab_shutdown,
+       .set_termios    = sunsab_set_termios,
+       .type           = sunsab_type,
+       .release_port   = sunsab_release_port,
+       .request_port   = sunsab_request_port,
+       .config_port    = sunsab_config_port,
+       .verify_port    = sunsab_verify_port,
+};
+
+static struct uart_driver sunsab_reg = {
+       .owner                  = THIS_MODULE,
+       .driver_name            = "sunsab",
+       .dev_name               = "ttyS",
+       .major                  = TTY_MAJOR,
+};
+
+static struct uart_sunsab_port *sunsab_ports;
+
+#ifdef CONFIG_SERIAL_SUNSAB_CONSOLE
+
+static void sunsab_console_putchar(struct uart_port *port, int c)
+{
+       struct uart_sunsab_port *up =
+               container_of(port, struct uart_sunsab_port, port);
+
+       sunsab_tec_wait(up);
+       writeb(c, &up->regs->w.tic);
+}
+
+static void sunsab_console_write(struct console *con, const char *s, unsigned n)
+{
+       struct uart_sunsab_port *up = &sunsab_ports[con->index];
+       unsigned long flags;
+       int locked = 1;
+
+       if (up->port.sysrq || oops_in_progress)
+               locked = spin_trylock_irqsave(&up->port.lock, flags);
+       else
+               spin_lock_irqsave(&up->port.lock, flags);
+
+       uart_console_write(&up->port, s, n, sunsab_console_putchar);
+       sunsab_tec_wait(up);
+
+       if (locked)
+               spin_unlock_irqrestore(&up->port.lock, flags);
+}
+
+static int sunsab_console_setup(struct console *con, char *options)
+{
+       struct uart_sunsab_port *up = &sunsab_ports[con->index];
+       unsigned long flags;
+       unsigned int baud, quot;
+
+       /*
+        * The console framework calls us for each and every port
+        * registered. Defer the console setup until the requested
+        * port has been properly discovered. A bit of a hack,
+        * though...
+        */
+       if (up->port.type != PORT_SUNSAB)
+               return -1;
+
+       printk("Console: ttyS%d (SAB82532)\n",
+              (sunsab_reg.minor - 64) + con->index);
+
+       sunserial_console_termios(con, up->port.dev->of_node);
+
+       switch (con->cflag & CBAUD) {
+       case B150: baud = 150; break;
+       case B300: baud = 300; break;
+       case B600: baud = 600; break;
+       case B1200: baud = 1200; break;
+       case B2400: baud = 2400; break;
+       case B4800: baud = 4800; break;
+       default: case B9600: baud = 9600; break;
+       case B19200: baud = 19200; break;
+       case B38400: baud = 38400; break;
+       case B57600: baud = 57600; break;
+       case B115200: baud = 115200; break;
+       case B230400: baud = 230400; break;
+       case B460800: baud = 460800; break;
+       }
+
+       /*
+        * Temporary fix.
+        */
+       spin_lock_init(&up->port.lock);
+
+       /*
+        * Initialize the hardware
+        */
+       sunsab_startup(&up->port);
+
+       spin_lock_irqsave(&up->port.lock, flags);
+
+       /*
+        * Finally, enable interrupts
+        */
+       up->interrupt_mask0 = SAB82532_IMR0_PERR | SAB82532_IMR0_FERR |
+                               SAB82532_IMR0_PLLA | SAB82532_IMR0_CDSC;
+       writeb(up->interrupt_mask0, &up->regs->w.imr0);
+       up->interrupt_mask1 = SAB82532_IMR1_BRKT | SAB82532_IMR1_ALLS |
+                               SAB82532_IMR1_XOFF | SAB82532_IMR1_TIN |
+                               SAB82532_IMR1_CSC | SAB82532_IMR1_XON |
+                               SAB82532_IMR1_XPR;
+       writeb(up->interrupt_mask1, &up->regs->w.imr1);
+
+       quot = uart_get_divisor(&up->port, baud);
+       sunsab_convert_to_sab(up, con->cflag, 0, baud, quot);
+       sunsab_set_mctrl(&up->port, TIOCM_DTR | TIOCM_RTS);
+
+       spin_unlock_irqrestore(&up->port.lock, flags);
+       
+       return 0;
+}
+
+static struct console sunsab_console = {
+       .name   =       "ttyS",
+       .write  =       sunsab_console_write,
+       .device =       uart_console_device,
+       .setup  =       sunsab_console_setup,
+       .flags  =       CON_PRINTBUFFER,
+       .index  =       -1,
+       .data   =       &sunsab_reg,
+};
+
+static inline struct console *SUNSAB_CONSOLE(void)
+{
+       return &sunsab_console;
+}
+#else
+#define SUNSAB_CONSOLE()       (NULL)
+#define sunsab_console_init()  do { } while (0)
+#endif
+
+static int sunsab_init_one(struct uart_sunsab_port *up,
+                                    struct platform_device *op,
+                                    unsigned long offset,
+                                    int line)
+{
+       up->port.line = line;
+       up->port.dev = &op->dev;
+
+       up->port.mapbase = op->resource[0].start + offset;
+       up->port.membase = of_ioremap(&op->resource[0], offset,
+                                     sizeof(union sab82532_async_regs),
+                                     "sab");
+       if (!up->port.membase)
+               return -ENOMEM;
+       up->regs = (union sab82532_async_regs __iomem *) up->port.membase;
+
+       up->port.irq = op->archdata.irqs[0];
+
+       up->port.fifosize = SAB82532_XMIT_FIFO_SIZE;
+       up->port.iotype = UPIO_MEM;
+
+       writeb(SAB82532_IPC_IC_ACT_LOW, &up->regs->w.ipc);
+
+       up->port.ops = &sunsab_pops;
+       up->port.type = PORT_SUNSAB;
+       up->port.uartclk = SAB_BASE_BAUD;
+
+       up->type = readb(&up->regs->r.vstr) & 0x0f;
+       writeb(~((1 << 1) | (1 << 2) | (1 << 4)), &up->regs->w.pcr);
+       writeb(0xff, &up->regs->w.pim);
+       if ((up->port.line & 0x1) == 0) {
+               up->pvr_dsr_bit = (1 << 0);
+               up->pvr_dtr_bit = (1 << 1);
+               up->gis_shift = 2;
+       } else {
+               up->pvr_dsr_bit = (1 << 3);
+               up->pvr_dtr_bit = (1 << 2);
+               up->gis_shift = 0;
+       }
+       up->cached_pvr = (1 << 1) | (1 << 2) | (1 << 4);
+       writeb(up->cached_pvr, &up->regs->w.pvr);
+       up->cached_mode = readb(&up->regs->rw.mode);
+       up->cached_mode |= SAB82532_MODE_FRTS;
+       writeb(up->cached_mode, &up->regs->rw.mode);
+       up->cached_mode |= SAB82532_MODE_RTS;
+       writeb(up->cached_mode, &up->regs->rw.mode);
+
+       up->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
+       up->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
+
+       return 0;
+}
+
+static int sab_probe(struct platform_device *op)
+{
+       static int inst;
+       struct uart_sunsab_port *up;
+       int err;
+
+       up = &sunsab_ports[inst * 2];
+
+       err = sunsab_init_one(&up[0], op,
+                             0,
+                             (inst * 2) + 0);
+       if (err)
+               goto out;
+
+       err = sunsab_init_one(&up[1], op,
+                             sizeof(union sab82532_async_regs),
+                             (inst * 2) + 1);
+       if (err)
+               goto out1;
+
+       sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
+                               &sunsab_reg, up[0].port.line,
+                               false);
+
+       sunserial_console_match(SUNSAB_CONSOLE(), op->dev.of_node,
+                               &sunsab_reg, up[1].port.line,
+                               false);
+
+       err = uart_add_one_port(&sunsab_reg, &up[0].port);
+       if (err)
+               goto out2;
+
+       err = uart_add_one_port(&sunsab_reg, &up[1].port);
+       if (err)
+               goto out3;
+
+       platform_set_drvdata(op, &up[0]);
+
+       inst++;
+
+       return 0;
+
+out3:
+       uart_remove_one_port(&sunsab_reg, &up[0].port);
+out2:
+       of_iounmap(&op->resource[0],
+                  up[1].port.membase,
+                  sizeof(union sab82532_async_regs));
+out1:
+       of_iounmap(&op->resource[0],
+                  up[0].port.membase,
+                  sizeof(union sab82532_async_regs));
+out:
+       return err;
+}
+
+static int sab_remove(struct platform_device *op)
+{
+       struct uart_sunsab_port *up = platform_get_drvdata(op);
+
+       uart_remove_one_port(&sunsab_reg, &up[1].port);
+       uart_remove_one_port(&sunsab_reg, &up[0].port);
+       of_iounmap(&op->resource[0],
+                  up[1].port.membase,
+                  sizeof(union sab82532_async_regs));
+       of_iounmap(&op->resource[0],
+                  up[0].port.membase,
+                  sizeof(union sab82532_async_regs));
+
+       return 0;
+}
+
+static const struct of_device_id sab_match[] = {
+       {
+               .name = "se",
+       },
+       {
+               .name = "serial",
+               .compatible = "sab82532",
+       },
+       {},
+};
+MODULE_DEVICE_TABLE(of, sab_match);
+
+static struct platform_driver sab_driver = {
+       .driver = {
+               .name = "sab",
+               .of_match_table = sab_match,
+       },
+       .probe          = sab_probe,
+       .remove         = sab_remove,
+};
+
+static int __init sunsab_init(void)
+{
+       struct device_node *dp;
+       int err;
+       int num_channels = 0;
+
+       for_each_node_by_name(dp, "se")
+               num_channels += 2;
+       for_each_node_by_name(dp, "serial") {
+               if (of_device_is_compatible(dp, "sab82532"))
+                       num_channels += 2;
+       }
+
+       if (num_channels) {
+               sunsab_ports = kzalloc(sizeof(struct uart_sunsab_port) *
+                                      num_channels, GFP_KERNEL);
+               if (!sunsab_ports)
+                       return -ENOMEM;
+
+               err = sunserial_register_minors(&sunsab_reg, num_channels);
+               if (err) {
+                       kfree(sunsab_ports);
+                       sunsab_ports = NULL;
+
+                       return err;
+               }
+       }
+
+       return platform_driver_register(&sab_driver);
+}
+
+static void __exit sunsab_exit(void)
+{
+       platform_driver_unregister(&sab_driver);
+       if (sunsab_reg.nr) {
+               sunserial_unregister_minors(&sunsab_reg, sunsab_reg.nr);
+       }
+
+       kfree(sunsab_ports);
+       sunsab_ports = NULL;
+}
+
+module_init(sunsab_init);
+module_exit(sunsab_exit);
+
+MODULE_AUTHOR("Eddie C. Dost and David S. Miller");
+MODULE_DESCRIPTION("Sun SAB82532 serial port driver");
+MODULE_LICENSE("GPL");