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