serial167.c

powerpc内核mpc8241linux系统下char驱动程序

   mapping is slightly different from serial.c because there
   is still the possibility of supporting 75 kbit/sec with
   the Cyclades board.)
 */
    if (i & CBAUDEX) {
	if (i == B57600)
	    i = 16;
	else if(i == B115200) 
	    i = 18;
#ifdef B78600
	else if(i == B78600) 
	    i = 17;
#endif
	else
	    info->tty->termios->c_cflag &= ~CBAUDEX;
    }
#endif
    if (i == 15) {
	    if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
		    i += 1;
	    if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
		    i += 3;
    }
    /* Don't ever change the speed of the console port.  It will
     * run at the speed specified in bootinfo, or at 19.2K */
    /* Actually, it should run at whatever speed 166Bug was using */
    /* Note info->timeout isn't used at present */
    if (info != serial_console_info) {
	info->tbpr = baud_bpr[i]; /* Tx BPR */
	info->tco = baud_co[i]; /* Tx CO */
	info->rbpr = baud_bpr[i]; /* Rx BPR */
	info->rco = baud_co[i] >> 5; /* Rx CO */
	if (baud_table[i] == 134) {
            info->timeout = (info->xmit_fifo_size*HZ*30/269) + 2;
            /* get it right for 134.5 baud */
	} else if (baud_table[i]) {
            info->timeout = (info->xmit_fifo_size*HZ*15/baud_table[i]) + 2;
        /* this needs to be propagated into the card info */
	} else {
            info->timeout = 0;
	}
    }
    /* By tradition (is it a standard?) a baud rate of zero
       implies the line should be/has been closed.  A bit
       later in this routine such a test is performed. */

    /* byte size and parity */
    info->cor7 = 0;
    info->cor6 = 0;
    info->cor5 = 0;
    info->cor4 = (info->default_threshold
		  ? info->default_threshold
		  : baud_cor4[i]); /* receive threshold */
    /* Following two lines added 101295, RGH. */
    /* It is obviously wrong to access CyCORx, and not info->corx here,
     * try and remember to fix it later! */
    channel = info->line;
    base_addr[CyCAR] = (u_char)channel;
    if (C_CLOCAL(info->tty)) {
	if (base_addr[CyIER] & CyMdmCh)
	    base_addr[CyIER] &= ~CyMdmCh; /* without modem intr */
			       /* ignore 1->0 modem transitions */
	if (base_addr[CyCOR4] & (CyDSR|CyCTS|CyDCD))
	    base_addr[CyCOR4] &= ~(CyDSR|CyCTS|CyDCD);
			       /* ignore 0->1 modem transitions */
	if (base_addr[CyCOR5] & (CyDSR|CyCTS|CyDCD))
	    base_addr[CyCOR5] &= ~(CyDSR|CyCTS|CyDCD);
    } else {
	if ((base_addr[CyIER] & CyMdmCh) != CyMdmCh)
	    base_addr[CyIER] |= CyMdmCh; /* with modem intr */
			       /* act on 1->0 modem transitions */
	if ((base_addr[CyCOR4] & (CyDSR|CyCTS|CyDCD)) != (CyDSR|CyCTS|CyDCD))
	    base_addr[CyCOR4] |= CyDSR|CyCTS|CyDCD;
			       /* act on 0->1 modem transitions */
	if ((base_addr[CyCOR5] & (CyDSR|CyCTS|CyDCD)) != (CyDSR|CyCTS|CyDCD))
	    base_addr[CyCOR5] |= CyDSR|CyCTS|CyDCD;
    }
    info->cor3 = (cflag & CSTOPB) ? Cy_2_STOP : Cy_1_STOP;
    info->cor2 = CyETC;
    switch(cflag & CSIZE){
    case CS5:
        info->cor1 = Cy_5_BITS;
        break;
    case CS6:
        info->cor1 = Cy_6_BITS;
        break;
    case CS7:
        info->cor1 = Cy_7_BITS;
        break;
    case CS8:
        info->cor1 = Cy_8_BITS;
        break;
    }
    if (cflag & PARENB){
        if (cflag & PARODD){
            info->cor1 |= CyPARITY_O;
        }else{
            info->cor1 |= CyPARITY_E;
        }
    }else{
        info->cor1 |= CyPARITY_NONE;
    }
	
    /* CTS flow control flag */
#if 0
    /* Don't complcate matters for now! RGH 141095 */
    if (cflag & CRTSCTS){
	info->flags |= ASYNC_CTS_FLOW;
	info->cor2 |= CyCtsAE;
    }else{
	info->flags &= ~ASYNC_CTS_FLOW;
	info->cor2 &= ~CyCtsAE;
    }
#endif
    if (cflag & CLOCAL)
	info->flags &= ~ASYNC_CHECK_CD;
    else
	info->flags |= ASYNC_CHECK_CD;

     /***********************************************
	The hardware option, CyRtsAO, presents RTS when
	the chip has characters to send.  Since most modems
	use RTS as reverse (inbound) flow control, this
	option is not used.  If inbound flow control is
	necessary, DTR can be programmed to provide the
	appropriate signals for use with a non-standard
	cable.  Contact Marcio Saito for details.
     ***********************************************/

    channel = info->line;

    save_flags(flags); cli();
	base_addr[CyCAR] = (u_char)channel;

	/* CyCMR set once only in mvme167_init_serial() */
	if (base_addr[CyLICR] != channel << 2)
	    base_addr[CyLICR] = channel << 2;
	if (base_addr[CyLIVR] != 0x5c)
	    base_addr[CyLIVR] = 0x5c;

       /* tx and rx baud rate */

	if (base_addr[CyCOR1] != info->cor1)
	    need_init_chan = 1;
	if (base_addr[CyTCOR] != info->tco)
	    base_addr[CyTCOR] = info->tco;
	if (base_addr[CyTBPR] != info->tbpr)
	    base_addr[CyTBPR] = info->tbpr;
	if (base_addr[CyRCOR] != info->rco)
	    base_addr[CyRCOR] = info->rco;
	if (base_addr[CyRBPR] != info->rbpr)
	    base_addr[CyRBPR] = info->rbpr;

	/* set line characteristics  according configuration */

	if (base_addr[CySCHR1] != START_CHAR(info->tty))
	    base_addr[CySCHR1] = START_CHAR(info->tty);
	if (base_addr[CySCHR2] != STOP_CHAR(info->tty))
	    base_addr[CySCHR2] = STOP_CHAR(info->tty);
	if (base_addr[CySCRL] != START_CHAR(info->tty))
	    base_addr[CySCRL] = START_CHAR(info->tty);
	if (base_addr[CySCRH] != START_CHAR(info->tty))
	    base_addr[CySCRH] = START_CHAR(info->tty);
	if (base_addr[CyCOR1] != info->cor1)
	    base_addr[CyCOR1] = info->cor1;
	if (base_addr[CyCOR2] != info->cor2)
	    base_addr[CyCOR2] = info->cor2;
	if (base_addr[CyCOR3] != info->cor3)
	    base_addr[CyCOR3] = info->cor3;
	if (base_addr[CyCOR4] != info->cor4)
	    base_addr[CyCOR4] = info->cor4;
	if (base_addr[CyCOR5] != info->cor5)
	    base_addr[CyCOR5] = info->cor5;
	if (base_addr[CyCOR6] != info->cor6)
	    base_addr[CyCOR6] = info->cor6;
	if (base_addr[CyCOR7] != info->cor7)
	    base_addr[CyCOR7] = info->cor7;

	if (need_init_chan)
	    write_cy_cmd(base_addr,CyINIT_CHAN);

	base_addr[CyCAR] = (u_char)channel; /* !!! Is this needed? */

	/* 2ms default rx timeout */
	ti = info->default_timeout ? info->default_timeout : 0x02;
	if (base_addr[CyRTPRL] != ti)
	    base_addr[CyRTPRL] = ti;
	if (base_addr[CyRTPRH] != 0)
	    base_addr[CyRTPRH] = 0;

	/* Set up RTS here also ????? RGH 141095 */
	if(i == 0){ /* baud rate is zero, turn off line */
	    if ((base_addr[CyMSVR2] & CyDTR) == CyDTR)
	        base_addr[CyMSVR2] = 0;
#ifdef SERIAL_DEBUG_DTR
            printk("cyc: %d: dropping DTR\n", __LINE__);
            printk("     status: 0x%x, 0x%x\n", base_addr[CyMSVR1], base_addr[CyMSVR2]);
#endif
	}else{
	    if ((base_addr[CyMSVR2] & CyDTR) != CyDTR)
	        base_addr[CyMSVR2] = CyDTR;
#ifdef SERIAL_DEBUG_DTR
            printk("cyc: %d: raising DTR\n", __LINE__);
            printk("     status: 0x%x, 0x%x\n", base_addr[CyMSVR1], base_addr[CyMSVR2]);
#endif
	}

	if (info->tty){
	    clear_bit(TTY_IO_ERROR, &info->tty->flags);
	}

    restore_flags(flags);

} /* config_setup */


static void
cy_put_char(struct tty_struct *tty, unsigned char ch)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
  unsigned long flags;

#ifdef SERIAL_DEBUG_IO
    printk("cy_put_char ttyS%d(0x%02x)\n", info->line, ch);
#endif

    if (serial_paranoia_check(info, tty->device, "cy_put_char"))
	return;

    if (!tty || !info->xmit_buf)
	return;

    save_flags(flags); cli();
	if (info->xmit_cnt >= PAGE_SIZE - 1) {
	    restore_flags(flags);
	    return;
	}

	info->xmit_buf[info->xmit_head++] = ch;
	info->xmit_head &= PAGE_SIZE - 1;
	info->xmit_cnt++;
    restore_flags(flags);
} /* cy_put_char */


static void
cy_flush_chars(struct tty_struct *tty)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
  unsigned long flags;
  volatile unsigned char *base_addr = (u_char *)BASE_ADDR;
  int channel;
				
#ifdef SERIAL_DEBUG_IO
    printk("cy_flush_chars ttyS%d\n", info->line); /* */
#endif

    if (serial_paranoia_check(info, tty->device, "cy_flush_chars"))
	return;

    if (info->xmit_cnt <= 0 || tty->stopped
    || tty->hw_stopped || !info->xmit_buf)
	return;

    channel = info->line;

    save_flags(flags); cli();
	base_addr[CyCAR] = channel;
	base_addr[CyIER] |= CyTxMpty;
    restore_flags(flags);
} /* cy_flush_chars */


/* This routine gets called when tty_write has put something into
    the write_queue.  If the port is not already transmitting stuff,
    start it off by enabling interrupts.  The interrupt service
    routine will then ensure that the characters are sent.  If the
    port is already active, there is no need to kick it.
 */
static int
cy_write(struct tty_struct * tty, int from_user,
           const unsigned char *buf, int count)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
  unsigned long flags;
  int c, total = 0;

#ifdef SERIAL_DEBUG_IO
    printk("cy_write ttyS%d\n", info->line); /* */
#endif

    if (serial_paranoia_check(info, tty->device, "cy_write")){
	return 0;
    }
	
    if (!tty || !info->xmit_buf || !tmp_buf){
        return 0;
    }

    while (1) {
        save_flags(flags); cli();		
	c = MIN(count, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
			   SERIAL_XMIT_SIZE - info->xmit_head));
	if (c <= 0){
	    restore_flags(flags);
	    break;
	}

	if (from_user) {
	    down(&tmp_buf_sem);
	    copy_from_user(tmp_buf, buf, c);
	    c = MIN(c, MIN(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
		       SERIAL_XMIT_SIZE - info->xmit_head));
	    memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
	    up(&tmp_buf_sem);
	} else
	    memcpy(info->xmit_buf + info->xmit_head, buf, c);
	info->xmit_head = (info->xmit_head + c) & (SERIAL_XMIT_SIZE-1);
	info->xmit_cnt += c;
	restore_flags(flags);
	buf += c;
	count -= c;
	total += c;
    }


    if (info->xmit_cnt
    && !tty->stopped
    && !tty->hw_stopped ) {
        start_xmit(info);
    }
    return total;
} /* cy_write */


static int
cy_write_room(struct tty_struct *tty)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
  int	ret;
				
#ifdef SERIAL_DEBUG_IO
    printk("cy_write_room ttyS%d\n", info->line); /* */
#endif

    if (serial_paranoia_check(info, tty->device, "cy_write_room"))
	return 0;
    ret = PAGE_SIZE - info->xmit_cnt - 1;
    if (ret < 0)
	ret = 0;
    return ret;
} /* cy_write_room */


static int
cy_chars_in_buffer(struct tty_struct *tty)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
				
#ifdef SERIAL_DEBUG_IO
    printk("cy_chars_in_buffer ttyS%d %d\n", info->line, info->xmit_cnt); /* */
#endif

    if (serial_paranoia_check(info, tty->device, "cy_chars_in_buffer"))
	return 0;

    return info->xmit_cnt;
} /* cy_chars_in_buffer */


static void
cy_flush_buffer(struct tty_struct *tty)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
  unsigned long flags;
				
#ifdef SERIAL_DEBUG_IO
    printk("cy_flush_buffer ttyS%d\n", info->line); /* */
#endif

    if (serial_paranoia_check(info, tty->device, "cy_flush_buffer"))
	return;
    save_flags(flags); cli();
	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
    restore_flags(flags);
    wake_up_interruptible(&tty->write_wait);
    if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP))
    && tty->ldisc.write_wakeup)
	(tty->ldisc.write_wakeup)(tty);
} /* cy_flush_buffer */


/* This routine is called by the upper-layer tty layer to signal
   that incoming characters should be throttled or that the
   throttle should be released.
 */
static void
cy_throttle(struct tty_struct * tty)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
  unsigned long flags;
  volatile unsigned char *base_addr = (u_char *)BASE_ADDR;
  int channel;

#ifdef SERIAL_DEBUG_THROTTLE
  char buf[64];
	
    printk("throttle %s: %d....\n", _tty_name(tty, buf),
	   tty->ldisc.chars_in_buffer(tty));
    printk("cy_throttle ttyS%d\n", info->line);
#endif

    if (serial_paranoia_check(info, tty->device, "cy_nthrottle")){
	    return;
    }

    if (I_IXOFF(tty)) {
	info->x_char = STOP_CHAR(tty);
	    /* Should use the "Send Special Character" feature!!! */
    }

    channel = info->line;

    save_flags(flags); cli();
	base_addr[CyCAR] = (u_char)channel;
	base_addr[CyMSVR1] = 0;
    restore_flags(flags);

    return;
} /* cy_throttle */


static void
cy_unthrottle(struct tty_struct * tty)
{
  struct cyclades_port *info = (struct cyclades_port *)tty->driver_data;
  unsigned long flags;
  volatile unsigned char *base_addr = (u_char *)BASE_ADDR;
  int channel;

#ifdef SERIAL_DEBUG_THROTTLE
  char buf[64];
	
    printk("throttle %s: %d....\n", _tty_name(tty, buf),
	   tty->ldisc.chars_in_buffer(tty));
    printk("cy_unthrottle ttyS%d\n", info->line);
#endif

    if (serial_paranoia_check(info, tty->device, "cy_nthrottle")){
	    return;
    }

    if (I_IXOFF(tty)) {
	info->x_char = START_CHAR(tty);
	/* Should use the "Send Special Character" feature!!! */
    }

    channel = info->line;

    save_flags(flags); cli();
	base_addr[CyCAR] = (u_char)channel;
	base_addr[CyMSVR1] = CyRTS;
    restore_flags(flags);

    return;
} /* cy_unthrottle */

static int
get_serial_info(struct cyclades_port * info,
                           struct serial_struct * retinfo)
{
  struct serial_struct tmp;

/* CP('g'); */