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 #ifndef SERIAL_PORT_DFNS
  10 #define SERIAL_PORT_DFNS
  11 #endif
  12
  13 static void start_serial_interrupt(int irq);
  14
  15 static const struct old_serial_port rs_table[] = {
  16         SERIAL_PORT_DFNS
  17 };
  18 static const struct old_serial_port *serstate;
  19 static int timeouts;
  20
  21 const struct old_serial_port *spk_serial_init(int index)
  22 {
  23         int baud = 9600, quot = 0;
  24         unsigned int cval = 0;
  25         int cflag = CREAD | HUPCL | CLOCAL | B9600 | CS8;
  26         const struct old_serial_port *ser = rs_table + index;
  27         int err;
  28
  29         /*      Divisor, bytesize and parity */
  30         quot = ser->baud_base / baud;
  31         cval = cflag & (CSIZE | CSTOPB);
  32 #if defined(__powerpc__) || defined(__alpha__)
  33         cval >>= 8;
  34 #else /* !__powerpc__ && !__alpha__ */
  35         cval >>= 4;
  36 #endif /* !__powerpc__ && !__alpha__ */
  37         if (cflag & PARENB)
  38                 cval |= UART_LCR_PARITY;
  39         if (!(cflag & PARODD))
  40                 cval |= UART_LCR_EPAR;
  41         if (synth_request_region(ser->port, 8)) {
  42                 /* try to take it back. */
  43                 pr_info("Ports not available, trying to steal them\n");
  44                 __release_region(&ioport_resource, ser->port, 8);
  45                 err = synth_request_region(ser->port, 8);
  46                 if (err) {
  47                         pr_warn("Unable to allocate port at %x, errno %i",
  48                                 ser->port, err);
  49                         return NULL;
  50                 }
  51         }
  52
  53         /*      Disable UART interrupts, set DTR and RTS high
  54          *      and set speed.
  55          */
  56         outb(cval | UART_LCR_DLAB, ser->port + UART_LCR);       /* set DLAB */
  57         outb(quot & 0xff, ser->port + UART_DLL);        /* LS of divisor */
  58         outb(quot >> 8, ser->port + UART_DLM);          /* MS of divisor */
  59         outb(cval, ser->port + UART_LCR);               /* reset DLAB */
  60
  61         /* Turn off Interrupts */
  62         outb(0, ser->port + UART_IER);
  63         outb(UART_MCR_DTR | UART_MCR_RTS, ser->port + UART_MCR);
  64
  65         /* If we read 0xff from the LSR, there is no UART here. */
  66         if (inb(ser->port + UART_LSR) == 0xff) {
  67                 synth_release_region(ser->port, 8);
  68                 serstate = NULL;
  69                 return NULL;
  70         }
  71
  72         mdelay(1);
  73         speakup_info.port_tts = ser->port;
  74         serstate = ser;
  75
  76         start_serial_interrupt(ser->irq);
  77
  78         return ser;
  79 }
  80
  81 static irqreturn_t synth_readbuf_handler(int irq, void *dev_id)
  82 {
  83         unsigned long flags;
  84 /*printk(KERN_ERR "in irq\n"); */
  85 /*pr_warn("in IRQ\n"); */
  86         int c;
  87
  88         spin_lock_irqsave(&speakup_info.spinlock, flags);
  89         while (inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR) {
  90
  91                 c = inb_p(speakup_info.port_tts+UART_RX);
  92                 synth->read_buff_add((u_char) c);
  93 /*printk(KERN_ERR "c = %d\n", c); */
  94 /*pr_warn("C = %d\n", c); */
  95         }
  96         spin_unlock_irqrestore(&speakup_info.spinlock, flags);
  97         return IRQ_HANDLED;
  98 }
  99
 100 static void start_serial_interrupt(int irq)
 101 {
 102         int rv;
 103
 104         if (!synth->read_buff_add)
 105                 return;
 106
 107         rv = request_irq(irq, synth_readbuf_handler, IRQF_SHARED,
 108                          "serial", (void *) synth_readbuf_handler);
 109
 110         if (rv)
 111                 pr_err("Unable to request Speakup serial I R Q\n");
 112         /* Set MCR */
 113         outb(UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2,
 114                         speakup_info.port_tts + UART_MCR);
 115         /* Turn on Interrupts */
 116         outb(UART_IER_MSI|UART_IER_RLSI|UART_IER_RDI,
 117                         speakup_info.port_tts + UART_IER);
 118         inb(speakup_info.port_tts+UART_LSR);
 119         inb(speakup_info.port_tts+UART_RX);
 120         inb(speakup_info.port_tts+UART_IIR);
 121         inb(speakup_info.port_tts+UART_MSR);
 122         outb(1, speakup_info.port_tts + UART_FCR);      /* Turn FIFO On */
 123 }
 124
 125 void spk_stop_serial_interrupt(void)
 126 {
 127         if (speakup_info.port_tts == 0)
 128                 return;
 129
 130         if (!synth->read_buff_add)
 131                 return;
 132
 133         /* Turn off interrupts */
 134         outb(0, speakup_info.port_tts+UART_IER);
 135         /* Free IRQ */
 136         free_irq(serstate->irq, (void *) synth_readbuf_handler);
 137 }
 138
 139 int spk_wait_for_xmitr(void)
 140 {
 141         int tmout = SPK_XMITR_TIMEOUT;
 142
 143         if ((synth->alive) && (timeouts >= NUM_DISABLE_TIMEOUTS)) {
 144                 pr_warn("%s: too many timeouts, deactivating speakup\n",
 145                         synth->long_name);
 146                 synth->alive = 0;
 147                 /* No synth any more, so nobody will restart TTYs, and we thus
 148                  * need to do it ourselves.  Now that there is no synth we can
 149                  * let application flood anyway
 150                  */
 151                 speakup_start_ttys();
 152                 timeouts = 0;
 153                 return 0;
 154         }
 155         while (spk_serial_tx_busy()) {
 156                 if (--tmout == 0) {
 157                         pr_warn("%s: timed out (tx busy)\n", synth->long_name);
 158                         timeouts++;
 159                         return 0;
 160                 }
 161                 udelay(1);
 162         }
 163         tmout = SPK_CTS_TIMEOUT;
 164         while (!((inb_p(speakup_info.port_tts + UART_MSR)) & UART_MSR_CTS)) {
 165                 /* CTS */
 166                 if (--tmout == 0) {
 167                         /* pr_warn("%s: timed out (cts)\n",
 168                          * synth->long_name);
 169                          */
 170                         timeouts++;
 171                         return 0;
 172                 }
 173                 udelay(1);
 174         }
 175         timeouts = 0;
 176         return 1;
 177 }
 178
 179 unsigned char spk_serial_in(void)
 180 {
 181         int tmout = SPK_SERIAL_TIMEOUT;
 182
 183         while (!(inb_p(speakup_info.port_tts + UART_LSR) & UART_LSR_DR)) {
 184                 if (--tmout == 0) {
 185                         pr_warn("time out while waiting for input.\n");
 186                         return 0xff;
 187                 }
 188                 udelay(1);
 189         }
 190         return inb_p(speakup_info.port_tts + UART_RX);
 191 }
 192 EXPORT_SYMBOL_GPL(spk_serial_in);
 193
 194 unsigned char spk_serial_in_nowait(void)
 195 {
 196         unsigned char lsr;
 197
 198         lsr = inb_p(speakup_info.port_tts + UART_LSR);
 199         if (!(lsr & UART_LSR_DR))
 200                 return 0;
 201         return inb_p(speakup_info.port_tts + UART_RX);
 202 }
 203 EXPORT_SYMBOL_GPL(spk_serial_in_nowait);
 204
 205 int spk_serial_out(const char ch)
 206 {
 207         if (synth->alive && spk_wait_for_xmitr()) {
 208                 outb_p(ch, speakup_info.port_tts);
 209                 return 1;
 210         }
 211         return 0;
 212 }
 213 EXPORT_SYMBOL_GPL(spk_serial_out);
 214
 215 void spk_serial_release(void)
 216 {
 217         if (speakup_info.port_tts == 0)
 218                 return;
 219         synth_release_region(speakup_info.port_tts, 8);
 220         speakup_info.port_tts = 0;
 221 }
 222 EXPORT_SYMBOL_GPL(spk_serial_release);