LXR linux/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
   9static void start_serial_interrupt(int irq);
  10
  11static struct serial_state rs_table[] = {
  12        SERIAL_PORT_DFNS
  13};
  14static struct serial_state *serstate;
  15static int timeouts;
  16
  17struct 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
  77static 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
  95static 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
 120void 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
 134int 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
 171unsigned 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}
 184EXPORT_SYMBOL_GPL(spk_serial_in);
 185
 186unsigned 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}
 195EXPORT_SYMBOL_GPL(spk_serial_in_nowait);
 196
 197int 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}
 205EXPORT_SYMBOL_GPL(spk_serial_out);
 206
 207void 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}
 214EXPORT_SYMBOL_GPL(spk_serial_release);
 215
 216