kernel/drivers/staging/speakup/serialio.c

   1 #include <linux/interrupt.h>
   2 #include <linux/ioport.h>
   3
   4 #include "spk_types.h"
   5 #include "speakup.h"
   6 #include "spk_priv.h"
   7 #include "serialio.h"
   8
   9 #include <linux/serial_core.h>
  10 /* WARNING:  Do not change this to <linux/serial.h> without testing that
  11  * SERIAL_PORT_DFNS does get defined to the appropriate value. */
  12 #include <asm/serial.h>
  13
  14 #ifndef SERIAL_PORT_DFNS
  15 #define SERIAL_PORT_DFNS
  16 #endif
  17
  18 static void start_serial_interrupt(int irq);
  19
  20 static const struct old_serial_port rs_table[] = {
  21         SERIAL_PORT_DFNS
  22 };
  23 static const struct old_serial_port *serstate;
  24 static int timeouts;
  25
  26 const struct old_serial_port *spk_serial_init(int index)
  27 {
  28         int baud = 9600, quot = 0;
  29         unsigned int cval = 0;
  30         int cflag = CREAD | HUPCL | CLOCAL | B9600 | CS8;
  31         const struct old_serial_port *ser;
  32         int err;
  33
  34         if (index >= ARRAY_SIZE(rs_table)) {
  35                 pr_info("no port info for ttyS%d\n", index);
  36                 return NULL;
  37         }
  38         ser = rs_table + index;
  39
  40         /*      Divisor, bytesize and parity */
  41         quot = ser->baud_base / baud;
  42         cval = cflag & (CSIZE | CSTOPB);
  43 #if defined(__powerpc__) || defined(__alpha__)
  44         cval >>= 8;
  45 #else /* !__powerpc__ && !__alpha__ */
  46         cval >>= 4;
  47 #endif /* !__powerpc__ && !__alpha__ */
  48         if (cflag & PARENB)
  49                 cval |= UART_LCR_PARITY;
  50         if (!(cflag & PARODD))
  51                 cval |= UART_LCR_EPAR;
  52         if (synth_request_region(ser->port, 8)) {
  53                 /* try to take it back. */
  54                 pr_info("Ports not available, trying to steal them\n");
  55                 __release_region(&ioport_resource, ser->port, 8);
  56                 err = synth_request_region(ser->port, 8);
  57                 if (err) {
  58                         pr_warn("Unable to allocate port at %x, errno %i",
  59                                 ser->port, err);
  60                         return NULL;
  61                 }
  62         }
  63
  64         /*      Disable UART interrupts, set DTR and RTS high
  65          *      and set speed.
  66          */
  67         outb(cval | UART_LCR_DLAB, ser->port + UART_LCR);       /* set DLAB */
  68         outb(quot & 0xff, ser->port + UART_DLL);        /* LS of divisor */
  69         outb(quot >> 8, ser->port + UART_DLM);          /* MS of divisor */
  70         outb(cval, ser->port + UART_LCR);               /* reset DLAB */
  71
  72         /* Turn off Interrupts */
  73         outb(0, ser->port + UART_IER);
  74         outb(UART_MCR_DTR | UART_MCR_RTS, ser->port + UART_MCR);
  75
  76         /* If we read 0xff from the LSR, there is no UART here. */
  77         if (inb(ser->port + UART_LSR) == 0xff) {
  78                 synth_release_region(ser->port, 8);
  79                 serstate = NULL;
  80                 return NULL;
  81         }
  82
  83         mdelay(1);
  84         speakup_info.port_tts = ser->port;
  85         serstate = ser;
  86
  87         start_serial_interrupt(ser->irq);
  88
  89         return ser;
  90 }
  91
  92 static irqreturn_t synth_readbuf_handler(int irq, void *dev_id)
  93 {
  94         unsigned long flags;
  95 /*printk(KERN_ERR "in irq\n"); */
  96 /*pr_warn("in IRQ\n"); */
  97         int c;
  98
  99         spin_lock_irqsave(&speakup_info.spinlock, flags);
 100         while (inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR) {
 101
 102                 c = inb_p(speakup_info.port_tts+UART_RX);
 103                 synth->read_buff_add((u_char) c);
 104 /*printk(KERN_ERR "c = %d\n", c); */
 105 /*pr_warn("C = %d\n", c); */
 106         }
 107         spin_unlock_irqrestore(&speakup_info.spinlock, flags);
 108         return IRQ_HANDLED;
 109 }
 110
 111 static void start_serial_interrupt(int irq)
 112 {
 113         int rv;
 114
 115         if (!synth->read_buff_add)
 116                 return;
 117
 118         rv = request_irq(irq, synth_readbuf_handler, IRQF_SHARED,
 119                          "serial", (void *) synth_readbuf_handler);
 120
 121         if (rv)
 122                 pr_err("Unable to request Speakup serial I R Q\n");
 123         /* Set MCR */
 124         outb(UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2,
 125                         speakup_info.port_tts + UART_MCR);
 126         /* Turn on Interrupts */
 127         outb(UART_IER_MSI|UART_IER_RLSI|UART_IER_RDI,
 128                         speakup_info.port_tts + UART_IER);
 129         inb(speakup_info.port_tts+UART_LSR);
 130         inb(speakup_info.port_tts+UART_RX);
 131         inb(speakup_info.port_tts+UART_IIR);
 132         inb(speakup_info.port_tts+UART_MSR);
 133         outb(1, speakup_info.port_tts + UART_FCR);      /* Turn FIFO On */
 134 }
 135
 136 void spk_stop_serial_interrupt(void)
 137 {
 138         if (speakup_info.port_tts == 0)
 139                 return;
 140
 141         if (!synth->read_buff_add)
 142                 return;
 143
 144         /* Turn off interrupts */
 145         outb(0, speakup_info.port_tts+UART_IER);
 146         /* Free IRQ */
 147         free_irq(serstate->irq, (void *) synth_readbuf_handler);
 148 }
 149
 150 int spk_wait_for_xmitr(void)
 151 {
 152         int tmout = SPK_XMITR_TIMEOUT;
 153
 154         if ((synth->alive) && (timeouts >= NUM_DISABLE_TIMEOUTS)) {
 155                 pr_warn("%s: too many timeouts, deactivating speakup\n",
 156                         synth->long_name);
 157                 synth->alive = 0;
 158                 /* No synth any more, so nobody will restart TTYs, and we thus
 159                  * need to do it ourselves.  Now that there is no synth we can
 160                  * let application flood anyway
 161                  */
 162                 speakup_start_ttys();
 163                 timeouts = 0;
 164                 return 0;
 165         }
 166         while (spk_serial_tx_busy()) {
 167                 if (--tmout == 0) {
 168                         pr_warn("%s: timed out (tx busy)\n", synth->long_name);
 169                         timeouts++;
 170                         return 0;
 171                 }
 172                 udelay(1);
 173         }
 174         tmout = SPK_CTS_TIMEOUT;
 175         while (!((inb_p(speakup_info.port_tts + UART_MSR)) & UART_MSR_CTS)) {
 176                 /* CTS */
 177                 if (--tmout == 0) {
 178                         /* pr_warn("%s: timed out (cts)\n",
 179                          * synth->long_name);
 180                          */
 181                         timeouts++;
 182                         return 0;
 183                 }
 184                 udelay(1);
 185         }
 186         timeouts = 0;
 187         return 1;
 188 }
 189
 190 unsigned char spk_serial_in(void)
 191 {
 192         int tmout = SPK_SERIAL_TIMEOUT;
 193
 194         while (!(inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR)) {
 195                 if (--tmout == 0) {
 196                         pr_warn("time out while waiting for input.\n");
 197                         return 0xff;
 198                 }
 199                 udelay(1);
 200         }
 201         return inb_p(speakup_info.port_tts + UART_RX);
 202 }
 203 EXPORT_SYMBOL_GPL(spk_serial_in);
 204
 205 unsigned char spk_serial_in_nowait(void)
 206 {
 207         unsigned char lsr;
 208
 209         lsr = inb_p(speakup_info.port_tts + UART_LSR);
 210         if (!(lsr & UART_LSR_DR))
 211                 return 0;
 212         return inb_p(speakup_info.port_tts + UART_RX);
 213 }
 214 EXPORT_SYMBOL_GPL(spk_serial_in_nowait);
 215
 216 int spk_serial_out(const char ch)
 217 {
 218         if (synth->alive && spk_wait_for_xmitr()) {
 219                 outb_p(ch, speakup_info.port_tts);
 220                 return 1;
 221         }
 222         return 0;
 223 }
 224 EXPORT_SYMBOL_GPL(spk_serial_out);
 225
 226 void spk_serial_release(void)
 227 {
 228         if (speakup_info.port_tts == 0)
 229                 return;
 230         synth_release_region(speakup_info.port_tts, 8);
 231         speakup_info.port_tts = 0;
 232 }
 233 EXPORT_SYMBOL_GPL(spk_serial_release);