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 static void start_serial_interrupt(int irq);
  10
  11 static struct serial_state rs_table[] = {
  12         SERIAL_PORT_DFNS
  13 };
  14 static struct serial_state *serstate;
  15 static int timeouts;
  16
  17 struct serial_state *spk_serial_init(int index)
  18 {
  19         int baud = 9600, quot = 0;
  20         unsigned int cval = 0;
  21         int cflag = CREAD | HUPCL | CLOCAL | B9600 | CS8;
  22         struct serial_state *ser = NULL;
  23         int err;
  24
  25         ser = rs_table + index;
  26         /*      Divisor, bytesize and parity */
  27         quot = ser->baud_base / baud;
  28         cval = cflag & (CSIZE | CSTOPB);
  29 #if defined(__powerpc__) || defined(__alpha__)
  30         cval >>= 8;
  31 #else /* !__powerpc__ && !__alpha__ */
  32         cval >>= 4;
  33 #endif /* !__powerpc__ && !__alpha__ */
  34         if (cflag & PARENB)
  35                 cval |= UART_LCR_PARITY;
  36         if (!(cflag & PARODD))
  37                 cval |= UART_LCR_EPAR;
  38         if (synth_request_region(ser->port, 8)) {
  39                 /* try to take it back. */
  40                 printk(KERN_INFO "Ports not available, trying to steal them\n");
  41                 __release_region(&ioport_resource, ser->port, 8);
  42                 err = synth_request_region(ser->port, 8);
  43                 if (err) {
  44                         pr_warn("Unable to allocate port at %lx, errno %i",
  45                                 ser->port, err);
  46                         return NULL;
  47                 }
  48         }
  49
  50         /*      Disable UART interrupts, set DTR and RTS high
  51          *      and set speed. */
  52         outb(cval | UART_LCR_DLAB, ser->port + UART_LCR);       /* set DLAB */
  53         outb(quot & 0xff, ser->port + UART_DLL);        /* LS of divisor */
  54         outb(quot >> 8, ser->port + UART_DLM);          /* MS of divisor */
  55         outb(cval, ser->port + UART_LCR);               /* reset DLAB */
  56
  57         /* Turn off Interrupts */
  58         outb(0, ser->port + UART_IER);
  59         outb(UART_MCR_DTR | UART_MCR_RTS, ser->port + UART_MCR);
  60
  61         /* If we read 0xff from the LSR, there is no UART here. */
  62         if (inb(ser->port + UART_LSR) == 0xff) {
  63                 synth_release_region(ser->port, 8);
  64                 serstate = NULL;
  65                 return NULL;
  66         }
  67
  68         mdelay(1);
  69         speakup_info.port_tts = ser->port;
  70         serstate = ser;
  71
  72         start_serial_interrupt(ser->irq);
  73
  74         return ser;
  75 }
  76
  77 static irqreturn_t synth_readbuf_handler(int irq, void *dev_id)
  78 {
  79         unsigned long flags;
  80 /*printk(KERN_ERR "in irq\n"); */
  81 /*pr_warn("in IRQ\n"); */
  82         int c;
  83         spk_lock(flags);
  84         while (inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR) {
  85
  86                 c = inb_p(speakup_info.port_tts+UART_RX);
  87                 synth->read_buff_add((u_char) c);
  88 /*printk(KERN_ERR "c = %d\n", c); */
  89 /*pr_warn("C = %d\n", c); */
  90         }
  91         spk_unlock(flags);
  92         return IRQ_HANDLED;
  93 }
  94
  95 static void start_serial_interrupt(int irq)
  96 {
  97         int rv;
  98
  99         if (synth->read_buff_add == NULL)
 100                 return;
 101
 102         rv = request_irq(irq, synth_readbuf_handler, IRQF_SHARED,
 103                          "serial", (void *) synth_readbuf_handler);
 104
 105         if (rv)
 106                 printk(KERN_ERR "Unable to request Speakup serial I R Q\n");
 107         /* Set MCR */
 108         outb(UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2,
 109                         speakup_info.port_tts + UART_MCR);
 110         /* Turn on Interrupts */
 111         outb(UART_IER_MSI|UART_IER_RLSI|UART_IER_RDI,
 112                         speakup_info.port_tts + UART_IER);
 113         inb(speakup_info.port_tts+UART_LSR);
 114         inb(speakup_info.port_tts+UART_RX);
 115         inb(speakup_info.port_tts+UART_IIR);
 116         inb(speakup_info.port_tts+UART_MSR);
 117         outb(1, speakup_info.port_tts + UART_FCR);      /* Turn FIFO On */
 118 }
 119
 120 void stop_serial_interrupt(void)
 121 {
 122         if (speakup_info.port_tts == 0)
 123                 return;
 124
 125         if (synth->read_buff_add == NULL)
 126                 return;
 127
 128         /* Turn off interrupts */
 129         outb(0, speakup_info.port_tts+UART_IER);
 130         /* Free IRQ */
 131         free_irq(serstate->irq, (void *) synth_readbuf_handler);
 132 }
 133
 134 int wait_for_xmitr(void)
 135 {
 136         int tmout = SPK_XMITR_TIMEOUT;
 137         if ((synth->alive) && (timeouts >= NUM_DISABLE_TIMEOUTS)) {
 138                 pr_warn("%s: too many timeouts, deactivating speakup\n",
 139                         synth->long_name);
 140                 synth->alive = 0;
 141                 /* No synth any more, so nobody will restart TTYs, and we thus
 142                  * need to do it ourselves.  Now that there is no synth we can
 143                  * let application flood anyway */
 144                 speakup_start_ttys();
 145                 timeouts = 0;
 146                 return 0;
 147         }
 148         while (spk_serial_tx_busy()) {
 149                 if (--tmout == 0) {
 150                         pr_warn("%s: timed out (tx busy)\n", synth->long_name);
 151                         timeouts++;
 152                         return 0;
 153                 }
 154                 udelay(1);
 155         }
 156         tmout = SPK_CTS_TIMEOUT;
 157         while (!((inb_p(speakup_info.port_tts + UART_MSR)) & UART_MSR_CTS)) {
 158                 /* CTS */
 159                 if (--tmout == 0) {
 160                         /* pr_warn("%s: timed out (cts)\n",
 161                          * synth->long_name); */
 162                         timeouts++;
 163                         return 0;
 164                 }
 165                 udelay(1);
 166         }
 167         timeouts = 0;
 168         return 1;
 169 }
 170
 171 unsigned char spk_serial_in(void)
 172 {
 173         int tmout = SPK_SERIAL_TIMEOUT;
 174
 175         while (!(inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR)) {
 176                 if (--tmout == 0) {
 177                         pr_warn("time out while waiting for input.\n");
 178                         return 0xff;
 179                 }
 180                 udelay(1);
 181         }
 182         return inb_p(speakup_info.port_tts + UART_RX);
 183 }
 184 EXPORT_SYMBOL_GPL(spk_serial_in);
 185
 186 unsigned char spk_serial_in_nowait(void)
 187 {
 188         unsigned char lsr;
 189
 190         lsr = inb_p(speakup_info.port_tts + UART_LSR);
 191         if (!(lsr & UART_LSR_DR))
 192                 return 0;
 193         return inb_p(speakup_info.port_tts + UART_RX);
 194 }
 195 EXPORT_SYMBOL_GPL(spk_serial_in_nowait);
 196
 197 int spk_serial_out(const char ch)
 198 {
 199         if (synth->alive && wait_for_xmitr()) {
 200                 outb_p(ch, speakup_info.port_tts);
 201                 return 1;
 202         }
 203         return 0;
 204 }
 205 EXPORT_SYMBOL_GPL(spk_serial_out);
 206
 207 void spk_serial_release(void)
 208 {
 209         if (speakup_info.port_tts == 0)
 210                 return;
 211         synth_release_region(speakup_info.port_tts, 8);
 212         speakup_info.port_tts = 0;
 213 }
 214 EXPORT_SYMBOL_GPL(spk_serial_release);
 215