sab82532.c

移植到2410开发板上的源代码

	if (cflag & PARENB) {
		dafo |= SAB82532_DAFO_PARE;
		bits++;
	}

	if (cflag & PARODD) {
#ifdef CMSPAR
		if (cflag & CMSPAR)
			dafo |= SAB82532_DAFO_PAR_MARK;
		else
#endif
			dafo |= SAB82532_DAFO_PAR_ODD;
	} else {
#ifdef CMSPAR
		if (cflag & CMSPAR)
			dafo |= SAB82532_DAFO_PAR_SPACE;
		else
#endif
			dafo |= SAB82532_DAFO_PAR_EVEN;
	}

	/* Determine EBRG values based on baud rate */
	info->baud = tty_get_baud_rate(info->tty);
	calc_ebrg(info->baud, &n, &m);
	
	ebrg = n | (m << 6);

	if (info->baud) {
		info->timeout = (info->xmit_fifo_size * HZ * bits) / info->baud;
		info->tec_timeout = (10 * 1000000) / info->baud;
		info->cec_timeout = info->tec_timeout >> 2;
	} else {
		info->timeout = 0;
		info->tec_timeout = SAB82532_MAX_TEC_TIMEOUT;
		info->cec_timeout = SAB82532_MAX_CEC_TIMEOUT;
	}
	info->timeout += HZ / 50;		/* Add .02 seconds of slop */

	/* CTS flow control flags */
	if (cflag & CRTSCTS)
		info->flags |= ASYNC_CTS_FLOW;
	else
		info->flags &= ~(ASYNC_CTS_FLOW);

	if (cflag & CLOCAL)
		info->flags &= ~(ASYNC_CHECK_CD);
	else
		info->flags |= ASYNC_CHECK_CD;
	if (info->tty)
		info->tty->hw_stopped = 0;

	/*
	 * Set up parity check flag
	 * XXX: not implemented, yet.
	 */
#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))

	/*
	 * Characters to ignore
	 * XXX: not implemented, yet.
	 */

	/*
	 * !!! ignore all characters if CREAD is not set
	 * XXX: not implemented, yet.
	 */
	if ((cflag & CREAD) == 0)
		info->ignore_status_mask |= SAB82532_ISR0_RPF |
					    SAB82532_ISR0_TCD |
					    SAB82532_ISR0_TIME;

	save_flags(flags); cli();
	sab82532_cec_wait(info);
	sab82532_tec_wait(info);
	writeb(dafo, &info->regs->w.dafo);
	writeb(ebrg & 0xff, &info->regs->w.bgr);
	writeb(readb(&info->regs->rw.ccr2) & ~(0xc0), &info->regs->rw.ccr2);
	writeb(readb(&info->regs->rw.ccr2) | ((ebrg >> 2) & 0xc0), &info->regs->rw.ccr2);
	if (info->flags & ASYNC_CTS_FLOW) {
		writeb(readb(&info->regs->rw.mode) & ~(SAB82532_MODE_RTS), &info->regs->rw.mode);
		writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_FRTS, &info->regs->rw.mode);
		writeb(readb(&info->regs->rw.mode) & ~(SAB82532_MODE_FCTS), &info->regs->rw.mode);
		info->interrupt_mask1 &= ~(SAB82532_IMR1_CSC);
		writeb(info->interrupt_mask1, &info->regs->w.imr1);
	} else {
		writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_RTS, &info->regs->rw.mode);
		writeb(readb(&info->regs->rw.mode) & ~(SAB82532_MODE_FRTS), &info->regs->rw.mode);
		writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_FCTS, &info->regs->rw.mode);
		info->interrupt_mask1 |= SAB82532_IMR1_CSC;
		writeb(info->interrupt_mask1, &info->regs->w.imr1);
	}
	writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_RAC, &info->regs->rw.mode);
	restore_flags(flags);
}

static void sab82532_put_char(struct tty_struct *tty, unsigned char ch)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->device, "sab82532_put_char"))
		return;

	if (!tty || !info->xmit.buf)
		return;

	save_flags(flags); cli();
	if (!CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE)) {
		restore_flags(flags);
		return;
	}

	info->xmit.buf[info->xmit.head] = ch;
	info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
	restore_flags(flags);
}

static void sab82532_flush_chars(struct tty_struct *tty)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->device, "sab82532_flush_chars"))
		return;

	if ((info->xmit.head == info->xmit.tail) ||
	    tty->stopped || tty->hw_stopped || !info->xmit.buf)
		return;

	save_flags(flags); cli();
	info->interrupt_mask1 &= ~(SAB82532_IMR1_XPR);
	writeb(info->interrupt_mask1, &info->regs->w.imr1);
	sab82532_start_tx(info);
	restore_flags(flags);
}

static int sab82532_write(struct tty_struct * tty, int from_user,
			  const unsigned char *buf, int count)
{
	int c, ret = 0;
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->device, "sab82532_write"))
		return 0;

	if (!tty || !info->xmit.buf || !tmp_buf)
		return 0;
	    
	save_flags(flags);
	if (from_user) {
		down(&tmp_buf_sem);
		while (1) {
			int c1;
			c = CIRC_SPACE_TO_END(info->xmit.head,
					      info->xmit.tail,
					      SERIAL_XMIT_SIZE);
			if (count < c)
				c = count;
			if (c <= 0)
				break;

			c -= copy_from_user(tmp_buf, buf, c);
			if (!c) {
				if (!ret)
					ret = -EFAULT;
				break;
			}
			cli();
			c1 = CIRC_SPACE_TO_END(info->xmit.head,
					       info->xmit.tail,
					       SERIAL_XMIT_SIZE);
			if (c1 < c)
				c = c1;
			memcpy(info->xmit.buf + info->xmit.head, tmp_buf, c);
			info->xmit.head = (info->xmit.head + c) & (SERIAL_XMIT_SIZE-1);
			restore_flags(flags);
			buf += c;
			count -= c;
			ret += c;
		}
		up(&tmp_buf_sem);
	} else {
		cli();
		while (1) {
			c = CIRC_SPACE_TO_END(info->xmit.head,
					      info->xmit.tail,
					      SERIAL_XMIT_SIZE);
			if (count < c)
				c = count;
			if (c <= 0)
				break;
			memcpy(info->xmit.buf + info->xmit.head, buf, c);
			info->xmit.head = (info->xmit.head + c) & (SERIAL_XMIT_SIZE-1);
			buf += c;
			count -= c;
			ret += c;
		}
		restore_flags(flags);
	}

	if ((info->xmit.head != info->xmit.tail) &&
	    !tty->stopped && !tty->hw_stopped) {
		info->interrupt_mask1 &= ~(SAB82532_IMR1_XPR);
		writeb(info->interrupt_mask1, &info->regs->w.imr1);
		sab82532_start_tx(info);
	}

	restore_flags(flags);
	return ret;
}

static int sab82532_write_room(struct tty_struct *tty)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;

	if (serial_paranoia_check(info, tty->device, "sab82532_write_room"))
		return 0;

	return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}

static int sab82532_chars_in_buffer(struct tty_struct *tty)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
				
	if (serial_paranoia_check(info, tty->device, "sab82532_chars_in_buffer"))
		return 0;

	return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}

static void sab82532_flush_buffer(struct tty_struct *tty)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->device, "sab82532_flush_buffer"))
		return;

	save_flags(flags); cli();
	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);
}

/*
 * This function is used to send a high-priority XON/XOFF character to
 * the device
 */
static void sab82532_send_xchar(struct tty_struct *tty, char ch)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->device, "sab82532_send_xchar"))
		return;

	save_flags(flags); cli();
	sab82532_tec_wait(info);
	writeb(ch, &info->regs->w.tic);
	restore_flags(flags);
}

/*
 * ------------------------------------------------------------
 * sab82532_throttle()
 * 
 * This routine is called by the upper-layer tty layer to signal that
 * incoming characters should be throttled.
 * ------------------------------------------------------------
 */
static void sab82532_throttle(struct tty_struct * tty)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
#ifdef SERIAL_DEBUG_THROTTLE
	char	buf[64];
	
	printk("throttle %s: %d....\n", _tty_name(tty, buf),
	       tty->ldisc.chars_in_buffer(tty));
#endif

	if (serial_paranoia_check(info, tty->device, "sab82532_throttle"))
		return;
	
	if (I_IXOFF(tty))
		sab82532_send_xchar(tty, STOP_CHAR(tty));

	if (tty->termios->c_cflag & CRTSCTS) {
		u8 mode = readb(&info->regs->r.mode);
		mode &= ~(SAB82532_MODE_FRTS | SAB82532_MODE_RTS);
		writeb(mode, &info->regs->w.mode);
	}
}

static void sab82532_unthrottle(struct tty_struct * tty)
{
	struct sab82532 *info = (struct sab82532 *)tty->driver_data;
#ifdef SERIAL_DEBUG_THROTTLE
	char	buf[64];
	
	printk("unthrottle %s: %d....\n", _tty_name(tty, buf),
	       tty->ldisc.chars_in_buffer(tty));
#endif

	if (serial_paranoia_check(info, tty->device, "sab82532_unthrottle"))
		return;
	
	if (I_IXOFF(tty)) {
		if (info->x_char)
			info->x_char = 0;
		else
			sab82532_send_xchar(tty, START_CHAR(tty));
	}

	if (tty->termios->c_cflag & CRTSCTS) {
		u8 mode = readb(&info->regs->r.mode);
		mode &= ~(SAB82532_MODE_RTS);
		mode |= SAB82532_MODE_FRTS;
		writeb(mode, &info->regs->w.mode);
	}
}

/*
 * ------------------------------------------------------------
 * sab82532_ioctl() and friends
 * ------------------------------------------------------------
 */

static int get_serial_info(struct sab82532 *info,
			   struct serial_struct *retinfo)
{
	struct serial_struct tmp;
   
	if (!retinfo)
		return -EFAULT;
	memset(&tmp, 0, sizeof(tmp));
	tmp.type = info->type;
	tmp.line = info->line;
	tmp.port = (unsigned long)info->regs;
	tmp.irq = info->irq;
	tmp.flags = info->flags;
	tmp.xmit_fifo_size = info->xmit_fifo_size;
	tmp.baud_base = info->baud_base;
	tmp.close_delay = info->close_delay;
	tmp.closing_wait = info->closing_wait;
	tmp.custom_divisor = info->custom_divisor;
	tmp.hub6 = 0;
	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
		return -EFAULT;
	return 0;
}

static int set_serial_info(struct sab82532 *info,
			   struct serial_struct *new_info)
{
	return 0;
}


/*
 * get_lsr_info - get line status register info
 *
 * Purpose: Let user call ioctl() to get info when the UART physically
 * 	    is emptied.  On bus types like RS485, the transmitter must
 * 	    release the bus after transmitting. This must be done when
 * 	    the transmit shift register is empty, not be done when the
 * 	    transmit holding register is empty.  This functionality
 * 	    allows an RS485 driver to be written in user space. 
 */
static int get_lsr_info(struct sab82532 * info, unsigned int *value)
{
	unsigned int result;

	result = (!info->xmit.buf && test_bit(SAB82532_ALLS, &info->irqflags))
							? TIOCSER_TEMT : 0;
	return put_user(result, value);
}


static int get_modem_info(struct sab82532 * info, unsigned int *value)
{
	unsigned int result;

	result =  ((readb(&info->regs->r.mode) & SAB82532_MODE_RTS) ? 
		    ((readb(&info->regs->r.mode) & SAB82532_MODE_FRTS) ? 0 : TIOCM_RTS)
							    : TIOCM_RTS)
		| ((readb(&info->regs->r.pvr) & info->pvr_dtr_bit) ? 0 : TIOCM_DTR)
		| ((readb(&info->regs->r.vstr) & SAB82532_VSTR_CD) ? 0 : TIOCM_CAR)
		| ((readb(&info->regs->r.pvr) & info->pvr_dsr_bit) ? 0 : TIOCM_DSR)
		| ((readb(&info->regs->r.star) & SAB82532_STAR_CTS) ? TIOCM_CTS : 0);
	return put_user(result,value);
}

static int set_modem_info(struct sab82532 * info, unsigned int cmd,
			  unsigned int *value)
{
	unsigned int arg;

	if (get_user(arg, value))
		return -EFAULT;
	switch (cmd) {
	case TIOCMBIS: 
		if (arg & TIOCM_RTS) {
			writeb(readb(&info->regs->rw.mode) & ~(SAB82532_MODE_FRTS), &info->regs->rw.mode);
			writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_RTS, &info->regs->rw.mode);
		}
		if (arg & TIOCM_DTR) {
			writeb(readb(&info->regs->rw.pvr) & ~(info->pvr_dtr_bit), &info->regs->rw.pvr);
		}
		break;
	case TIOCMBIC:
		if (arg & TIOCM_RTS) {
			writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_FRTS, &info->regs->rw.mode);
			writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_RTS, &info->regs->rw.mode);
		}
		if (arg & TIOCM_DTR) {
			writeb(readb(&info->regs->rw.pvr) | info->pvr_dtr_bit, &info->regs->rw.pvr);
		}
		break;
	case TIOCMSET:
		if (arg & TIOCM_RTS) {
			writeb(readb(&info->regs->rw.mode) & ~(SAB82532_MODE_FRTS), &info->regs->rw.mode);
			writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_RTS, &info->regs->rw.mode);
		} else {
			writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_FRTS, &info->regs->rw.mode);
			writeb(readb(&info->regs->rw.mode) | SAB82532_MODE_RTS, &info->regs->rw.mode);
		}
		if (arg & TIOCM_DTR) {
			writeb(readb(&info->regs->rw.pvr) & ~(info->pvr_dtr_bit), &info->regs->rw.pvr);
		} else {
			writeb(readb(&info->regs->rw.pvr) | info->pvr_dtr_bit, &info->regs->rw.pvr);
		}
		break;
	default:
		return -EINVAL;
	}
	return 0;
}

/*
 * This routine sends a break character out the serial port.
 */
static void sab82532_break(struct tty_struct *tty, int break_state)
{
	struct sab82532 * info = (struct sab82532 *)tty->driver_data;
	unsigned long flags;

	if (serial_paranoia_check(info, tty->device, "sab82532_break"))
		return;

	if (!info->regs)
		return;

#ifdef SERIAL_DEBUG_SEND_BREAK
	printk("sab82532_break(%d) jiff=%lu...", break_state, jiffies);
#endif
	save_flags(flags); cli();
	if (break_state == -1)
		writeb(readb(&info->regs->rw.dafo) | SAB82532_DAFO_XBRK, &info->regs->rw.dafo);
	else
		writeb(readb(&info->regs->rw.dafo) & ~(SAB82532_DAFO_XBRK), &info->regs->rw.dafo);
	restore_flags(flags);
}


static int sab82532_ioctl(struct tty_struct *tty, struct file * file,
		    unsigned int cmd, unsigned long arg)
{
	struct sab82532 * info = (struct sab82532 *)tty->driver_data;
	struct async_icount cprev, cnow;	/* kernel counter temps */
	struct serial_icounter_struct *p_cuser;	/* user space */

	if (serial_paranoia_check(info, tty->device, "sab82532_ioctl"))
		return -ENODEV;

	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
	    (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT) &&
	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {