isicom.c

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			outsw(base, port->xmit_buf+port->xmit_tail,word_count);
			port->xmit_tail = (port->xmit_tail
				+ (word_count << 1)) & (SERIAL_XMIT_SIZE - 1);
			txcount -= (word_count << 1);
			port->xmit_cnt -= (word_count << 1);
			if (cnt & 0x0001) {
				residue = YES;
				wrd = port->xmit_buf[port->xmit_tail];
				port->xmit_tail = (port->xmit_tail + 1)
					& (SERIAL_XMIT_SIZE - 1);
				port->xmit_cnt--;
				txcount--;
			}
		}

		InterruptTheCard(base);
		if (port->xmit_cnt <= 0)
			port->status &= ~ISI_TXOK;
		if (port->xmit_cnt <= WAKEUP_CHARS)
			tty_wakeup(tty);
	}

unlock:
	spin_unlock_irqrestore(&isi_card[card].card_lock, flags);
	/*	schedule another tx for hopefully in about 10ms	*/
sched_again:
	mod_timer(&tx, jiffies + msecs_to_jiffies(10));
}

/*
 *	Main interrupt handler routine
 */

static irqreturn_t isicom_interrupt(int irq, void *dev_id)
{
	struct isi_board *card = dev_id;
	struct isi_port *port;
	struct tty_struct *tty;
	unsigned long base;
	u16 header, word_count, count, channel;
	short byte_count;
	unsigned char *rp;

	if (!card || !(card->status & FIRMWARE_LOADED))
		return IRQ_NONE;

	base = card->base;

	/* did the card interrupt us? */
	if (!(inw(base + 0x0e) & 0x02))
		return IRQ_NONE;

	spin_lock(&card->card_lock);

	/*
	 * disable any interrupts from the PCI card and lower the
	 * interrupt line
	 */
	outw(0x8000, base+0x04);
	ClearInterrupt(base);

	inw(base);		/* get the dummy word out */
	header = inw(base);
	channel = (header & 0x7800) >> card->shift_count;
	byte_count = header & 0xff;

	if (channel + 1 > card->port_count) {
		printk(KERN_WARNING "ISICOM: isicom_interrupt(0x%lx): "
			"%d(channel) > port_count.\n", base, channel+1);
		outw(0x0000, base+0x04); /* enable interrupts */
		spin_unlock(&card->card_lock);
		return IRQ_HANDLED;
	}
	port = card->ports + channel;
	if (!(port->flags & ASYNC_INITIALIZED)) {
		outw(0x0000, base+0x04); /* enable interrupts */
		spin_unlock(&card->card_lock);
		return IRQ_HANDLED;
	}

	tty = port->tty;
	if (tty == NULL) {
		word_count = byte_count >> 1;
		while(byte_count > 1) {
			inw(base);
			byte_count -= 2;
		}
		if (byte_count & 0x01)
			inw(base);
		outw(0x0000, base+0x04); /* enable interrupts */
		spin_unlock(&card->card_lock);
		return IRQ_HANDLED;
	}

	if (header & 0x8000) {		/* Status Packet */
		header = inw(base);
		switch(header & 0xff) {
		case 0:	/* Change in EIA signals */
			if (port->flags & ASYNC_CHECK_CD) {
				if (port->status & ISI_DCD) {
					if (!(header & ISI_DCD)) {
					/* Carrier has been lost  */
						pr_dbg("interrupt: DCD->low.\n"
							);
						port->status &= ~ISI_DCD;
						tty_hangup(tty);
					}
				} else if (header & ISI_DCD) {
				/* Carrier has been detected */
					pr_dbg("interrupt: DCD->high.\n");
					port->status |= ISI_DCD;
					wake_up_interruptible(&port->open_wait);
				}
			} else {
				if (header & ISI_DCD)
					port->status |= ISI_DCD;
				else
					port->status &= ~ISI_DCD;
			}

			if (port->flags & ASYNC_CTS_FLOW) {
				if (port->tty->hw_stopped) {
					if (header & ISI_CTS) {
						port->tty->hw_stopped = 0;
						/* start tx ing */
						port->status |= (ISI_TXOK
							| ISI_CTS);
						tty_wakeup(tty);
					}
				} else if (!(header & ISI_CTS)) {
					port->tty->hw_stopped = 1;
					/* stop tx ing */
					port->status &= ~(ISI_TXOK | ISI_CTS);
				}
			} else {
				if (header & ISI_CTS)
					port->status |= ISI_CTS;
				else
					port->status &= ~ISI_CTS;
			}

			if (header & ISI_DSR)
				port->status |= ISI_DSR;
			else
				port->status &= ~ISI_DSR;

			if (header & ISI_RI)
				port->status |= ISI_RI;
			else
				port->status &= ~ISI_RI;

			break;

		case 1:	/* Received Break !!! */
			tty_insert_flip_char(tty, 0, TTY_BREAK);
			if (port->flags & ASYNC_SAK)
				do_SAK(tty);
			tty_flip_buffer_push(tty);
			break;

		case 2:	/* Statistics		 */
			pr_dbg("isicom_interrupt: stats!!!.\n");
			break;

		default:
			pr_dbg("Intr: Unknown code in status packet.\n");
			break;
		}
	} else {				/* Data   Packet */

		count = tty_prepare_flip_string(tty, &rp, byte_count & ~1);
		pr_dbg("Intr: Can rx %d of %d bytes.\n", count, byte_count);
		word_count = count >> 1;
		insw(base, rp, word_count);
		byte_count -= (word_count << 1);
		if (count & 0x0001) {
			tty_insert_flip_char(tty,  inw(base) & 0xff,
				TTY_NORMAL);
			byte_count -= 2;
		}
		if (byte_count > 0) {
			pr_dbg("Intr(0x%lx:%d): Flip buffer overflow! dropping "
				"bytes...\n", base, channel + 1);
			while(byte_count > 0) { /* drain out unread xtra data */
				inw(base);
				byte_count -= 2;
			}
		}
		tty_flip_buffer_push(tty);
	}
	outw(0x0000, base+0x04); /* enable interrupts */
	spin_unlock(&card->card_lock);

	return IRQ_HANDLED;
}

static void isicom_config_port(struct isi_port *port)
{
	struct isi_board *card = port->card;
	struct tty_struct *tty;
	unsigned long baud;
	unsigned long base = card->base;
	u16 channel_setup, channel = port->channel,
		shift_count = card->shift_count;
	unsigned char flow_ctrl;

	if (!(tty = port->tty) || !tty->termios)
		return;
	baud = C_BAUD(tty);
	if (baud & CBAUDEX) {
		baud &= ~CBAUDEX;

		/*  if CBAUDEX bit is on and the baud is set to either 50 or 75
		 *  then the card is programmed for 57.6Kbps or 115Kbps
		 *  respectively.
		 */

		/* 1,2,3,4 => 57.6, 115.2, 230, 460 kbps resp. */
		if (baud < 1 || baud > 4)
			port->tty->termios->c_cflag &= ~CBAUDEX;
		else
			baud += 15;
	}
	if (baud == 15) {

		/*  the ASYNC_SPD_HI and ASYNC_SPD_VHI options are set
		 *  by the set_serial_info ioctl ... this is done by
		 *  the 'setserial' utility.
		 */

		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
			baud++; /*  57.6 Kbps */
		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
			baud +=2; /*  115  Kbps */
		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
			baud += 3; /* 230 kbps*/
		if ((port->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
			baud += 4; /* 460 kbps*/
	}
	if (linuxb_to_isib[baud] == -1) {
		/* hang up */
		drop_dtr(port);
		return;
	}
	else
		raise_dtr(port);

	if (WaitTillCardIsFree(base) == 0) {
		outw(0x8000 | (channel << shift_count) |0x03, base);
		outw(linuxb_to_isib[baud] << 8 | 0x03, base);
		channel_setup = 0;
		switch(C_CSIZE(tty)) {
		case CS5:
			channel_setup |= ISICOM_CS5;
			break;
		case CS6:
			channel_setup |= ISICOM_CS6;
			break;
		case CS7:
			channel_setup |= ISICOM_CS7;
			break;
		case CS8:
			channel_setup |= ISICOM_CS8;
			break;
		}

		if (C_CSTOPB(tty))
			channel_setup |= ISICOM_2SB;
		if (C_PARENB(tty)) {
			channel_setup |= ISICOM_EVPAR;
			if (C_PARODD(tty))
				channel_setup |= ISICOM_ODPAR;
		}
		outw(channel_setup, base);
		InterruptTheCard(base);
	}
	if (C_CLOCAL(tty))
		port->flags &= ~ASYNC_CHECK_CD;
	else
		port->flags |= ASYNC_CHECK_CD;

	/* flow control settings ...*/
	flow_ctrl = 0;
	port->flags &= ~ASYNC_CTS_FLOW;
	if (C_CRTSCTS(tty)) {
		port->flags |= ASYNC_CTS_FLOW;
		flow_ctrl |= ISICOM_CTSRTS;
	}
	if (I_IXON(tty))
		flow_ctrl |= ISICOM_RESPOND_XONXOFF;
	if (I_IXOFF(tty))
		flow_ctrl |= ISICOM_INITIATE_XONXOFF;

	if (WaitTillCardIsFree(base) == 0) {
		outw(0x8000 | (channel << shift_count) |0x04, base);
		outw(flow_ctrl << 8 | 0x05, base);
		outw((STOP_CHAR(tty)) << 8 | (START_CHAR(tty)), base);
		InterruptTheCard(base);
	}

	/*	rx enabled -> enable port for rx on the card	*/
	if (C_CREAD(tty)) {
		card->port_status |= (1 << channel);
		outw(card->port_status, base + 0x02);
	}
}

/* open et all */

static inline void isicom_setup_board(struct isi_board *bp)
{
	int channel;
	struct isi_port *port;
	unsigned long flags;

	spin_lock_irqsave(&bp->card_lock, flags);
	if (bp->status & BOARD_ACTIVE) {
		spin_unlock_irqrestore(&bp->card_lock, flags);
		return;
	}
	port = bp->ports;
	bp->status |= BOARD_ACTIVE;
	for (channel = 0; channel < bp->port_count; channel++, port++)
		drop_dtr_rts(port);
	spin_unlock_irqrestore(&bp->card_lock, flags);
}

static int isicom_setup_port(struct isi_port *port)
{
	struct isi_board *card = port->card;
	unsigned long flags;

	if (port->flags & ASYNC_INITIALIZED) {
		return 0;
	}
	if (!port->xmit_buf) {
		unsigned long page;

		if (!(page = get_zeroed_page(GFP_KERNEL)))
			return -ENOMEM;

		if (port->xmit_buf) {
			free_page(page);
			return -ERESTARTSYS;
		}
		port->xmit_buf = (unsigned char *) page;
	}

	spin_lock_irqsave(&card->card_lock, flags);
	if (port->tty)
		clear_bit(TTY_IO_ERROR, &port->tty->flags);
	if (port->count == 1)
		card->count++;

	port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;

	/*	discard any residual data	*/
	if (WaitTillCardIsFree(card->base) == 0) {
		outw(0x8000 | (port->channel << card->shift_count) | 0x02,
				card->base);
		outw(((ISICOM_KILLTX | ISICOM_KILLRX) << 8) | 0x06, card->base);
		InterruptTheCard(card->base);
	}

	isicom_config_port(port);
	port->flags |= ASYNC_INITIALIZED;
	spin_unlock_irqrestore(&card->card_lock, flags);

	return 0;
}

static int block_til_ready(struct tty_struct *tty, struct file *filp,
	struct isi_port *port)
{
	struct isi_board *card = port->card;
	int do_clocal = 0, retval;
	unsigned long flags;
	DECLARE_WAITQUEUE(wait, current);

	/* block if port is in the process of being closed */

	if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
		pr_dbg("block_til_ready: close in progress.\n");
		interruptible_sleep_on(&port->close_wait);
		if (port->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	/* if non-blocking mode is set ... */

	if ((filp->f_flags & O_NONBLOCK) ||
			(tty->flags & (1 << TTY_IO_ERROR))) {
		pr_dbg("block_til_ready: non-block mode.\n");
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	if (C_CLOCAL(tty))
		do_clocal = 1;

	/* block waiting for DCD to be asserted, and while
						callout dev is busy */
	retval = 0;
	add_wait_queue(&port->open_wait, &wait);

	spin_lock_irqsave(&card->card_lock, flags);
	if (!tty_hung_up_p(filp))
		port->count--;
	port->blocked_open++;
	spin_unlock_irqrestore(&card->card_lock, flags);

	while (1) {
		raise_dtr_rts(port);

		set_current_state(TASK_INTERRUPTIBLE);
		if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) {
			if (port->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;
			break;
		}
		if (!(port->flags & ASYNC_CLOSING) &&
				(do_clocal || (port->status & ISI_DCD))) {
			break;
		}
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&port->open_wait, &wait);
	spin_lock_irqsave(&card->card_lock, flags);
	if (!tty_hung_up_p(filp))
		port->count++;
	port->blocked_open--;
	spin_unlock_irqrestore(&card->card_lock, flags);
	if (retval)
		return retval;
	port->flags |= ASYNC_NORMAL_ACTIVE;
	return 0;
}

static int isicom_open(struct tty_struct *tty, struct file *filp)
{
	struct isi_port *port;
	struct isi_board *card;
	unsigned int board;
	int error, line;

	line = tty->index;
	if (line < 0 || line > PORT_COUNT-1)
		return -ENODEV;
	board = BOARD(line);
	card = &isi_card[board];

	if (!(card->status & FIRMWARE_LOADED))
		return -ENODEV;

	/*  open on a port greater than the port count for the card !!! */
	if (line > ((board * 16) + card->port_count - 1))
		return -ENODEV;

	port = &isi_ports[line];
	if (isicom_paranoia_check(port, tty->name, "isicom_open"))
		return -ENODEV;

	isicom_setup_board(card);

	port->count++;
	tty->driver_data = port;