specialix.c

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#if 0
	/* It's time to find IRQ for this board */
	for (retries = 0; retries < 5 && irqs <= 0; retries++) {
		irqs = probe_irq_on();
		sx_init_CD186x(bp);	       		/* Reset CD186x chip       */
		sx_out(bp, CD186x_CAR, 2);               /* Select port 2          */
		sx_wait_CCR(bp);
		sx_out(bp, CD186x_CCR, CCR_TXEN);        /* Enable transmitter     */
		sx_out(bp, CD186x_IER, IER_TXRDY);       /* Enable tx empty intr   */
		msleep(50);
		irqs = probe_irq_off(irqs);

		dprintk (SX_DEBUG_INIT, "SRSR = %02x, ", sx_in(bp, CD186x_SRSR));
		dprintk (SX_DEBUG_INIT, "TRAR = %02x, ", sx_in(bp, CD186x_TRAR));
		dprintk (SX_DEBUG_INIT, "GIVR = %02x, ", sx_in(bp, CD186x_GIVR));
		dprintk (SX_DEBUG_INIT, "GICR = %02x, ", sx_in(bp, CD186x_GICR));
		dprintk (SX_DEBUG_INIT, "\n");

		/* Reset CD186x again      */
		if (!sx_init_CD186x(bp)) {
			/* Hmmm. This is dead code anyway. */
		}

		dprintk (SX_DEBUG_INIT "val1 = %02x, val2 = %02x, val3 = %02x.\n",
		        val1, val2, val3);

	}

#if 0
	if (irqs <= 0) {
		printk(KERN_ERR "sx%d: Can't find IRQ for specialix IO8+ board at 0x%03x.\n",
		       board_No(bp), bp->base);
		sx_release_io_range(bp);
		func_exit();
		return 1;
	}
#endif
	printk (KERN_INFO "Started with irq=%d, but now have irq=%d.\n", bp->irq, irqs);
	if (irqs > 0)
		bp->irq = irqs;
#endif
	/* Reset CD186x again  */
	if (!sx_init_CD186x(bp)) {
		sx_release_io_range(bp);
		func_exit();
		return 1;
	}

	sx_request_io_range(bp);
	bp->flags |= SX_BOARD_PRESENT;

	/* Chip           revcode   pkgtype
	                  GFRCR     SRCR bit 7
	   CD180 rev B    0x81      0
	   CD180 rev C    0x82      0
	   CD1864 rev A   0x82      1
	   CD1865 rev A   0x83      1  -- Do not use!!! Does not work.
	   CD1865 rev B   0x84      1
	 -- Thanks to Gwen Wang, Cirrus Logic.
	 */

	switch (sx_in_off(bp, CD186x_GFRCR)) {
	case 0x82:chip = 1864;rev='A';break;
	case 0x83:chip = 1865;rev='A';break;
	case 0x84:chip = 1865;rev='B';break;
	case 0x85:chip = 1865;rev='C';break; /* Does not exist at this time */
	default:chip=-1;rev='x';
	}

	dprintk (SX_DEBUG_INIT, " GFCR = 0x%02x\n", sx_in_off(bp, CD186x_GFRCR) );

#ifdef SPECIALIX_TIMER
	setup_timer(&missed_irq_timer, missed_irq, (unsigned long)bp);
	mod_timer(&missed_irq_timer, jiffies + sx_poll);
#endif

	printk(KERN_INFO"sx%d: specialix IO8+ board detected at 0x%03x, IRQ %d, CD%d Rev. %c.\n",
	       board_No(bp),
	       bp->base, bp->irq,
	       chip, rev);

	func_exit();
	return 0;
}

/*
 *
 *  Interrupt processing routines.
 * */

static inline void sx_mark_event(struct specialix_port * port, int event)
{
	func_enter();

	set_bit(event, &port->event);
	schedule_work(&port->tqueue);

	func_exit();
}


static inline struct specialix_port * sx_get_port(struct specialix_board * bp,
					       unsigned char const * what)
{
	unsigned char channel;
	struct specialix_port * port = NULL;

	channel = sx_in(bp, CD186x_GICR) >> GICR_CHAN_OFF;
	dprintk (SX_DEBUG_CHAN, "channel: %d\n", channel);
	if (channel < CD186x_NCH) {
		port = &sx_port[board_No(bp) * SX_NPORT + channel];
		dprintk (SX_DEBUG_CHAN, "port: %d %p flags: 0x%x\n",board_No(bp) * SX_NPORT + channel,  port, port->flags & ASYNC_INITIALIZED);

		if (port->flags & ASYNC_INITIALIZED) {
			dprintk (SX_DEBUG_CHAN, "port: %d %p\n", channel, port);
			func_exit();
			return port;
		}
	}
	printk(KERN_INFO "sx%d: %s interrupt from invalid port %d\n",
	       board_No(bp), what, channel);
	return NULL;
}


static inline void sx_receive_exc(struct specialix_board * bp)
{
	struct specialix_port *port;
	struct tty_struct *tty;
	unsigned char status;
	unsigned char ch, flag;

	func_enter();

	port = sx_get_port(bp, "Receive");
	if (!port) {
		dprintk (SX_DEBUG_RX, "Hmm, couldn't find port.\n");
		func_exit();
		return;
	}
	tty = port->tty;

	status = sx_in(bp, CD186x_RCSR);

	dprintk (SX_DEBUG_RX, "status: 0x%x\n", status);
	if (status & RCSR_OE) {
		port->overrun++;
		dprintk(SX_DEBUG_FIFO, "sx%d: port %d: Overrun. Total %ld overruns.\n",
		       board_No(bp), port_No(port), port->overrun);
	}
	status &= port->mark_mask;

	/* This flip buffer check needs to be below the reading of the
	   status register to reset the chip's IRQ.... */
	if (tty_buffer_request_room(tty, 1) == 0) {
		dprintk(SX_DEBUG_FIFO, "sx%d: port %d: Working around flip buffer overflow.\n",
		       board_No(bp), port_No(port));
		func_exit();
		return;
	}

	ch = sx_in(bp, CD186x_RDR);
	if (!status) {
		func_exit();
		return;
	}
	if (status & RCSR_TOUT) {
		printk(KERN_INFO "sx%d: port %d: Receiver timeout. Hardware problems ?\n",
		       board_No(bp), port_No(port));
		func_exit();
		return;

	} else if (status & RCSR_BREAK) {
		dprintk(SX_DEBUG_RX, "sx%d: port %d: Handling break...\n",
		       board_No(bp), port_No(port));
		flag = TTY_BREAK;
		if (port->flags & ASYNC_SAK)
			do_SAK(tty);

	} else if (status & RCSR_PE)
		flag = TTY_PARITY;

	else if (status & RCSR_FE)
		flag = TTY_FRAME;

	else if (status & RCSR_OE)
		flag = TTY_OVERRUN;

	else
		flag = TTY_NORMAL;

	if(tty_insert_flip_char(tty, ch, flag))
		tty_flip_buffer_push(tty);
	func_exit();
}


static inline void sx_receive(struct specialix_board * bp)
{
	struct specialix_port *port;
	struct tty_struct *tty;
	unsigned char count;

	func_enter();

	if (!(port = sx_get_port(bp, "Receive"))) {
		dprintk (SX_DEBUG_RX, "Hmm, couldn't find port.\n");
		func_exit();
		return;
	}
	tty = port->tty;

	count = sx_in(bp, CD186x_RDCR);
	dprintk (SX_DEBUG_RX, "port: %p: count: %d\n", port, count);
	port->hits[count > 8 ? 9 : count]++;

	tty_buffer_request_room(tty, count);

	while (count--)
		tty_insert_flip_char(tty, sx_in(bp, CD186x_RDR), TTY_NORMAL);
	tty_flip_buffer_push(tty);
	func_exit();
}


static inline void sx_transmit(struct specialix_board * bp)
{
	struct specialix_port *port;
	struct tty_struct *tty;
	unsigned char count;

	func_enter();
	if (!(port = sx_get_port(bp, "Transmit"))) {
		func_exit();
		return;
	}
	dprintk (SX_DEBUG_TX, "port: %p\n", port);
	tty = port->tty;

	if (port->IER & IER_TXEMPTY) {
		/* FIFO drained */
		sx_out(bp, CD186x_CAR, port_No(port));
		port->IER &= ~IER_TXEMPTY;
		sx_out(bp, CD186x_IER, port->IER);
		func_exit();
		return;
	}

	if ((port->xmit_cnt <= 0 && !port->break_length)
	    || tty->stopped || tty->hw_stopped) {
		sx_out(bp, CD186x_CAR, port_No(port));
		port->IER &= ~IER_TXRDY;
		sx_out(bp, CD186x_IER, port->IER);
		func_exit();
		return;
	}

	if (port->break_length) {
		if (port->break_length > 0) {
			if (port->COR2 & COR2_ETC) {
				sx_out(bp, CD186x_TDR, CD186x_C_ESC);
				sx_out(bp, CD186x_TDR, CD186x_C_SBRK);
				port->COR2 &= ~COR2_ETC;
			}
			count = min_t(int, port->break_length, 0xff);
			sx_out(bp, CD186x_TDR, CD186x_C_ESC);
			sx_out(bp, CD186x_TDR, CD186x_C_DELAY);
			sx_out(bp, CD186x_TDR, count);
			if (!(port->break_length -= count))
				port->break_length--;
		} else {
			sx_out(bp, CD186x_TDR, CD186x_C_ESC);
			sx_out(bp, CD186x_TDR, CD186x_C_EBRK);
			sx_out(bp, CD186x_COR2, port->COR2);
			sx_wait_CCR(bp);
			sx_out(bp, CD186x_CCR, CCR_CORCHG2);
			port->break_length = 0;
		}

		func_exit();
		return;
	}

	count = CD186x_NFIFO;
	do {
		sx_out(bp, CD186x_TDR, port->xmit_buf[port->xmit_tail++]);
		port->xmit_tail = port->xmit_tail & (SERIAL_XMIT_SIZE-1);
		if (--port->xmit_cnt <= 0)
			break;
	} while (--count > 0);

	if (port->xmit_cnt <= 0) {
		sx_out(bp, CD186x_CAR, port_No(port));
		port->IER &= ~IER_TXRDY;
		sx_out(bp, CD186x_IER, port->IER);
	}
	if (port->xmit_cnt <= port->wakeup_chars)
		sx_mark_event(port, RS_EVENT_WRITE_WAKEUP);

	func_exit();
}


static inline void sx_check_modem(struct specialix_board * bp)
{
	struct specialix_port *port;
	struct tty_struct *tty;
	unsigned char mcr;
	int msvr_cd;

	dprintk (SX_DEBUG_SIGNALS, "Modem intr. ");
	if (!(port = sx_get_port(bp, "Modem")))
		return;

	tty = port->tty;

	mcr = sx_in(bp, CD186x_MCR);
	printk ("mcr = %02x.\n", mcr);

	if ((mcr & MCR_CDCHG)) {
		dprintk (SX_DEBUG_SIGNALS, "CD just changed... ");
		msvr_cd = sx_in(bp, CD186x_MSVR) & MSVR_CD;
		if (msvr_cd) {
			dprintk (SX_DEBUG_SIGNALS, "Waking up guys in open.\n");
			wake_up_interruptible(&port->open_wait);
		} else {
			dprintk (SX_DEBUG_SIGNALS, "Sending HUP.\n");
			schedule_work(&port->tqueue_hangup);
		}
	}

#ifdef SPECIALIX_BRAIN_DAMAGED_CTS
	if (mcr & MCR_CTSCHG) {
		if (sx_in(bp, CD186x_MSVR) & MSVR_CTS) {
			tty->hw_stopped = 0;
			port->IER |= IER_TXRDY;
			if (port->xmit_cnt <= port->wakeup_chars)
				sx_mark_event(port, RS_EVENT_WRITE_WAKEUP);
		} else {
			tty->hw_stopped = 1;
			port->IER &= ~IER_TXRDY;
		}
		sx_out(bp, CD186x_IER, port->IER);
	}
	if (mcr & MCR_DSSXHG) {
		if (sx_in(bp, CD186x_MSVR) & MSVR_DSR) {
			tty->hw_stopped = 0;
			port->IER |= IER_TXRDY;
			if (port->xmit_cnt <= port->wakeup_chars)
				sx_mark_event(port, RS_EVENT_WRITE_WAKEUP);
		} else {
			tty->hw_stopped = 1;
			port->IER &= ~IER_TXRDY;
		}
		sx_out(bp, CD186x_IER, port->IER);
	}
#endif /* SPECIALIX_BRAIN_DAMAGED_CTS */

	/* Clear change bits */
	sx_out(bp, CD186x_MCR, 0);
}


/* The main interrupt processing routine */
static irqreturn_t sx_interrupt(int irq, void *dev_id)
{
	unsigned char status;
	unsigned char ack;
	struct specialix_board *bp;
	unsigned long loop = 0;
	int saved_reg;
	unsigned long flags;

	func_enter();

	bp = dev_id;
	spin_lock_irqsave(&bp->lock, flags);

	dprintk (SX_DEBUG_FLOW, "enter %s port %d room: %ld\n", __FUNCTION__, port_No(sx_get_port(bp, "INT")), SERIAL_XMIT_SIZE - sx_get_port(bp, "ITN")->xmit_cnt - 1);
	if (!(bp->flags & SX_BOARD_ACTIVE)) {
		dprintk (SX_DEBUG_IRQ, "sx: False interrupt. irq %d.\n", irq);
		spin_unlock_irqrestore(&bp->lock, flags);
		func_exit();
		return IRQ_NONE;
	}

	saved_reg = bp->reg;

	while ((++loop < 16) && (status = (sx_in(bp, CD186x_SRSR) &
	                                   (SRSR_RREQint |
		                            SRSR_TREQint |
	                                    SRSR_MREQint)))) {
		if (status & SRSR_RREQint) {
			ack = sx_in(bp, CD186x_RRAR);

			if (ack == (SX_ID | GIVR_IT_RCV))
				sx_receive(bp);
			else if (ack == (SX_ID | GIVR_IT_REXC))
				sx_receive_exc(bp);
			else
				printk(KERN_ERR "sx%d: status: 0x%x Bad receive ack 0x%02x.\n",
				       board_No(bp), status, ack);

		} else if (status & SRSR_TREQint) {
			ack = sx_in(bp, CD186x_TRAR);

			if (ack == (SX_ID | GIVR_IT_TX))
				sx_transmit(bp);
			else
				printk(KERN_ERR "sx%d: status: 0x%x Bad transmit ack 0x%02x. port: %d\n",
				       board_No(bp), status, ack, port_No (sx_get_port (bp, "Int")));
		} else if (status & SRSR_MREQint) {
			ack = sx_in(bp, CD186x_MRAR);

			if (ack == (SX_ID | GIVR_IT_MODEM))
				sx_check_modem(bp);
			else
				printk(KERN_ERR "sx%d: status: 0x%x Bad modem ack 0x%02x.\n",
				       board_No(bp), status, ack);

		}

		sx_out(bp, CD186x_EOIR, 0);   /* Mark end of interrupt */
	}
	bp->reg = saved_reg;
	outb (bp->reg, bp->base + SX_ADDR_REG);
	spin_unlock_irqrestore(&bp->lock, flags);
	func_exit();
	return IRQ_HANDLED;
}


/*
 *  Routines for open & close processing.
 */

static void turn_ints_off (struct specialix_board *bp)
{
	unsigned long flags;

	func_enter();
	if (bp->flags & SX_BOARD_IS_PCI) {
		/* This was intended for enabeling the interrupt on the
		 * PCI card. However it seems that it's already enabled
		 * and as PCI interrupts can be shared, there is no real
		 * reason to have to turn it off. */
	}

	spin_lock_irqsave(&bp->lock, flags);
	(void) sx_in_off (bp, 0); /* Turn off interrupts. */
	spin_unlock_irqrestore(&bp->lock, flags);

	func_exit();
}

static void turn_ints_on (struct specialix_board *bp)
{
	unsigned long flags;

	func_enter();

	if (bp->flags & SX_BOARD_IS_PCI) {
		/* play with the PCI chip. See comment above. */
	}
	spin_lock_irqsave(&bp->lock, flags);
	(void) sx_in (bp, 0); /* Turn ON interrupts. */
	spin_unlock_irqrestore(&bp->lock, flags);

	func_exit();
}


/* Called with disabled interrupts */
static inline int sx_setup_board(struct specialix_board * bp)
{
	int error;

	if (bp->flags & SX_BOARD_ACTIVE)
		return 0;

	if (bp->flags & SX_BOARD_IS_PCI)
		error = request_irq(bp->irq, sx_interrupt, IRQF_DISABLED | IRQF_SHARED, "specialix IO8+", bp);
	else
		error = request_irq(bp->irq, sx_interrupt, IRQF_DISABLED, "specialix IO8+", bp);

	if (error)
		return error;

	turn_ints_on (bp);
	bp->flags |= SX_BOARD_ACTIVE;

	return 0;
}


/* Called with disabled interrupts */
static inline void sx_shutdown_board(struct specialix_board *bp)
{
	func_enter();

	if (!(bp->flags & SX_BOARD_ACTIVE)) {
		func_exit();
		return;
	}

	bp->flags &= ~SX_BOARD_ACTIVE;

	dprintk (SX_DEBUG_IRQ, "Freeing IRQ%d for board %d.\n",
		 bp->irq, board_No (bp));
	free_irq(bp->irq, bp);

	turn_ints_off (bp);