rocket.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 2,368 行 · 第 1/5 页

#ifdef ROCKET_DEBUG_THROTTLE
	printk(KERN_INFO "throttle %s: %d....\n", tty->name,
	       tty->ldisc.chars_in_buffer(tty));
#endif

	if (rocket_paranoia_check(info, "rp_throttle"))
		return;

	cp = &info->channel;
	if (I_IXOFF(tty))
		rp_send_xchar(tty, STOP_CHAR(tty));

	sClrRTS(&info->channel);
}

static void rp_unthrottle(struct tty_struct *tty)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	CHANNEL_t *cp;
#ifdef ROCKET_DEBUG_THROTTLE
	printk(KERN_INFO "unthrottle %s: %d....\n", tty->name,
	       tty->ldisc.chars_in_buffer(tty));
#endif

	if (rocket_paranoia_check(info, "rp_throttle"))
		return;

	cp = &info->channel;
	if (I_IXOFF(tty))
		rp_send_xchar(tty, START_CHAR(tty));

	sSetRTS(&info->channel);
}

/*
 * ------------------------------------------------------------
 * rp_stop() and rp_start()
 *
 * This routines are called before setting or resetting tty->stopped.
 * They enable or disable transmitter interrupts, as necessary.
 * ------------------------------------------------------------
 */
static void rp_stop(struct tty_struct *tty)
{
	struct r_port *info = (struct r_port *) tty->driver_data;

#ifdef ROCKET_DEBUG_FLOW
	printk(KERN_INFO "stop %s: %d %d....\n", tty->name,
	       info->xmit_cnt, info->xmit_fifo_room);
#endif

	if (rocket_paranoia_check(info, "rp_stop"))
		return;

	if (sGetTxCnt(&info->channel))
		sDisTransmit(&info->channel);
}

static void rp_start(struct tty_struct *tty)
{
	struct r_port *info = (struct r_port *) tty->driver_data;

#ifdef ROCKET_DEBUG_FLOW
	printk(KERN_INFO "start %s: %d %d....\n", tty->name,
	       info->xmit_cnt, info->xmit_fifo_room);
#endif

	if (rocket_paranoia_check(info, "rp_stop"))
		return;

	sEnTransmit(&info->channel);
	set_bit((info->aiop * 8) + info->chan,
		(void *) &xmit_flags[info->board]);
}

/*
 * rp_wait_until_sent() --- wait until the transmitter is empty
 */
static void rp_wait_until_sent(struct tty_struct *tty, int timeout)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	CHANNEL_t *cp;
	unsigned long orig_jiffies;
	int check_time, exit_time;
	int txcnt;

	if (rocket_paranoia_check(info, "rp_wait_until_sent"))
		return;

	cp = &info->channel;

	orig_jiffies = jiffies;
#ifdef ROCKET_DEBUG_WAIT_UNTIL_SENT
	printk(KERN_INFO "In RP_wait_until_sent(%d) (jiff=%lu)...", timeout,
	       jiffies);
	printk(KERN_INFO "cps=%d...", info->cps);
#endif
	while (1) {
		txcnt = sGetTxCnt(cp);
		if (!txcnt) {
			if (sGetChanStatusLo(cp) & TXSHRMT)
				break;
			check_time = (HZ / info->cps) / 5;
		} else {
			check_time = HZ * txcnt / info->cps;
		}
		if (timeout) {
			exit_time = orig_jiffies + timeout - jiffies;
			if (exit_time <= 0)
				break;
			if (exit_time < check_time)
				check_time = exit_time;
		}
		if (check_time == 0)
			check_time = 1;
#ifdef ROCKET_DEBUG_WAIT_UNTIL_SENT
		printk(KERN_INFO "txcnt = %d (jiff=%lu,check=%d)...", txcnt, jiffies, check_time);
#endif
		current->state = TASK_INTERRUPTIBLE;
		schedule_timeout(check_time);
		if (signal_pending(current))
			break;
	}
	current->state = TASK_RUNNING;
#ifdef ROCKET_DEBUG_WAIT_UNTIL_SENT
	printk(KERN_INFO "txcnt = %d (jiff=%lu)...done\n", txcnt, jiffies);
#endif
}

/*
 * rp_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
static void rp_hangup(struct tty_struct *tty)
{
	CHANNEL_t *cp;
	struct r_port *info = (struct r_port *) tty->driver_data;

	if (rocket_paranoia_check(info, "rp_hangup"))
		return;

#if (defined(ROCKET_DEBUG_OPEN) || defined(ROCKET_DEBUG_HANGUP))
	printk(KERN_INFO "rp_hangup of ttyR%d...", info->line);
#endif
	rp_flush_buffer(tty);
	if (info->flags & ROCKET_CLOSING)
		return;
	if (info->count) 
		atomic_dec(&rp_num_ports_open);
	clear_bit((info->aiop * 8) + info->chan, (void *) &xmit_flags[info->board]);

	info->count = 0;
	info->flags &= ~ROCKET_NORMAL_ACTIVE;
	info->tty = NULL;

	cp = &info->channel;
	sDisRxFIFO(cp);
	sDisTransmit(cp);
	sDisInterrupts(cp, (TXINT_EN | MCINT_EN | RXINT_EN | SRCINT_EN | CHANINT_EN));
	sDisCTSFlowCtl(cp);
	sDisTxSoftFlowCtl(cp);
	sClrTxXOFF(cp);
	info->flags &= ~ROCKET_INITIALIZED;

	wake_up_interruptible(&info->open_wait);
}

/*
 *  Exception handler - write char routine.  The RocketPort driver uses a
 *  double-buffering strategy, with the twist that if the in-memory CPU
 *  buffer is empty, and there's space in the transmit FIFO, the
 *  writing routines will write directly to transmit FIFO.
 *  Write buffer and counters protected by spinlocks
 */
static void rp_put_char(struct tty_struct *tty, unsigned char ch)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	CHANNEL_t *cp;
	unsigned long flags;

	if (rocket_paranoia_check(info, "rp_put_char"))
		return;

	/*  Grab the port write semaphore, locking out other processes that try to write to this port */
	down(&info->write_sem);

#ifdef ROCKET_DEBUG_WRITE
	printk(KERN_INFO "rp_put_char %c...", ch);
#endif

	spin_lock_irqsave(&info->slock, flags);
	cp = &info->channel;

	if (!tty->stopped && !tty->hw_stopped && info->xmit_fifo_room == 0)
		info->xmit_fifo_room = TXFIFO_SIZE - sGetTxCnt(cp);

	if (tty->stopped || tty->hw_stopped || info->xmit_fifo_room == 0 || info->xmit_cnt != 0) {
		info->xmit_buf[info->xmit_head++] = ch;
		info->xmit_head &= XMIT_BUF_SIZE - 1;
		info->xmit_cnt++;
		set_bit((info->aiop * 8) + info->chan, (void *) &xmit_flags[info->board]);
	} else {
		sOutB(sGetTxRxDataIO(cp), ch);
		info->xmit_fifo_room--;
	}
	spin_unlock_irqrestore(&info->slock, flags);
	up(&info->write_sem);
}

/*
 *  Exception handler - write routine, called when user app writes to the device.
 *  A per port write semaphore is used to protect from another process writing to
 *  this port at the same time.  This other process could be running on the other CPU
 *  or get control of the CPU if the copy_from_user() blocks due to a page fault (swapped out). 
 *  Spinlocks protect the info xmit members.
 */
static int rp_write(struct tty_struct *tty, int from_user,
		    const unsigned char *buf, int count)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	CHANNEL_t *cp;
	const unsigned char *b;
	int c, retval = 0;
	unsigned long flags;

	if (count <= 0 || rocket_paranoia_check(info, "rp_write"))
		return 0;

	down_interruptible(&info->write_sem);

#ifdef ROCKET_DEBUG_WRITE
	printk(KERN_INFO "rp_write %d chars...", count);
#endif
	cp = &info->channel;

	if (!tty->stopped && !tty->hw_stopped && info->xmit_fifo_room < count)
		info->xmit_fifo_room = TXFIFO_SIZE - sGetTxCnt(cp);

        /*
	 *  If the write queue for the port is empty, and there is FIFO space, stuff bytes 
	 *  into FIFO.  Use the write queue for temp storage.
         */
	if (!tty->stopped && !tty->hw_stopped && info->xmit_cnt == 0 && info->xmit_fifo_room > 0) {
		c = min(count, info->xmit_fifo_room);
		b = buf;
		if (from_user) {
			if (copy_from_user(info->xmit_buf, buf, c)) {
				retval = -EFAULT;
				goto end;
			}
			if (info->tty == 0)
				goto end;
			b = info->xmit_buf;
			c = min(c, info->xmit_fifo_room);
		}

		/*  Push data into FIFO, 2 bytes at a time */
		sOutStrW(sGetTxRxDataIO(cp), (unsigned short *) b, c / 2);

		/*  If there is a byte remaining, write it */
		if (c & 1)
			sOutB(sGetTxRxDataIO(cp), b[c - 1]);

		retval += c;
		buf += c;
		count -= c;

		spin_lock_irqsave(&info->slock, flags);
		info->xmit_fifo_room -= c;
		spin_unlock_irqrestore(&info->slock, flags);
	}

	/* If count is zero, we wrote it all and are done */
	if (!count)
		goto end;

	/*  Write remaining data into the port's xmit_buf */
	while (1) {
		if (info->tty == 0)	/*   Seemingly obligatory check... */
			goto end;

		c = min(count, min(XMIT_BUF_SIZE - info->xmit_cnt - 1, XMIT_BUF_SIZE - info->xmit_head));
		if (c <= 0)
			break;

		b = buf;
		if (from_user) {
			if (copy_from_user(info->xmit_buf + info->xmit_head, b, c)) {
				retval = -EFAULT;
				goto end_intr;
			} else {
				memcpy(info->xmit_buf + info->xmit_head, b, c);
			}
		}

		spin_lock_irqsave(&info->slock, flags);
		info->xmit_head =
		    (info->xmit_head + c) & (XMIT_BUF_SIZE - 1);
		info->xmit_cnt += c;
		spin_unlock_irqrestore(&info->slock, flags);

		buf += c;
		count -= c;
		retval += c;
	}

end_intr:
	if ((retval > 0) && !tty->stopped && !tty->hw_stopped)
		set_bit((info->aiop * 8) + info->chan, (void *) &xmit_flags[info->board]);
	
end:
 	if (info->xmit_cnt < WAKEUP_CHARS) {
 		tty_wakeup(tty);
		wake_up_interruptible(&tty->write_wait);
#ifdef ROCKETPORT_HAVE_POLL_WAIT
		wake_up_interruptible(&tty->poll_wait);
#endif
	}
	up(&info->write_sem);
	return retval;
}

/*
 * Return the number of characters that can be sent.  We estimate
 * only using the in-memory transmit buffer only, and ignore the
 * potential space in the transmit FIFO.
 */
static int rp_write_room(struct tty_struct *tty)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	int ret;

	if (rocket_paranoia_check(info, "rp_write_room"))
		return 0;

	ret = XMIT_BUF_SIZE - info->xmit_cnt - 1;
	if (ret < 0)
		ret = 0;
#ifdef ROCKET_DEBUG_WRITE
	printk(KERN_INFO "rp_write_room returns %d...", ret);
#endif
	return ret;
}

/*
 * Return the number of characters in the buffer.  Again, this only
 * counts those characters in the in-memory transmit buffer.
 */
static int rp_chars_in_buffer(struct tty_struct *tty)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	CHANNEL_t *cp;

	if (rocket_paranoia_check(info, "rp_chars_in_buffer"))
		return 0;

	cp = &info->channel;

#ifdef ROCKET_DEBUG_WRITE
	printk(KERN_INFO "rp_chars_in_buffer returns %d...", info->xmit_cnt);
#endif
	return info->xmit_cnt;
}

/*
 *  Flushes the TX fifo for a port, deletes data in the xmit_buf stored in the
 *  r_port struct for the port.  Note that spinlock are used to protect info members,
 *  do not call this function if the spinlock is already held.
 */
static void rp_flush_buffer(struct tty_struct *tty)
{
	struct r_port *info = (struct r_port *) tty->driver_data;
	CHANNEL_t *cp;
	unsigned long flags;

	if (rocket_paranoia_check(info, "rp_flush_buffer"))
		return;

	spin_lock_irqsave(&info->slock, flags);
	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
	spin_unlock_irqrestore(&info->slock, flags);

	wake_up_interruptible(&tty->write_wait);
#ifdef ROCKETPORT_HAVE_POLL_WAIT
	wake_up_interruptible(&tty->poll_wait);
#endif
	tty_wakeup(tty);

	cp = &info->channel;
	sFlushTxFIFO(cp);
}

#ifdef CONFIG_PCI

/*
 *  Called when a PCI card is found.  Retrieves and stores model information,
 *  init's aiopic and serial port hardware.
 *  Inputs:  i is the board number (0-n)
 */
__init int register_PCI(int i, struct pci_dev *dev)
{
	int num_aiops, aiop, max_num_aiops, num_chan, chan;
	unsigned int aiopio[MAX_AIOPS_PER_BOARD];
	char *str, *board_type;
	CONTROLLER_t *ctlp;

	int fast_clock = 0;
	int altChanRingIndicator = 0;
	int ports_per_aiop = 8;
	int ret;
	unsigned int class_rev;
	WordIO_t ConfigIO = 0;
	ByteIO_t UPCIRingInd = 0;

	if (!dev || pci_enable_device(dev))
		return 0;

	rcktpt_io_addr[i] = pci_resource_start(dev, 0);
	ret = pci_read_config_dword(dev, PCI_CLASS_REVISION, &class_rev);

	if (ret) {
		printk(KERN_INFO "  Error during register_PCI(), unable to read config dword \n");
		return 0;
	}

	rcktpt_type[i] = ROCKET_TYPE_NORMAL;
	rocketModel[i].loadrm2 = 0;
	rocketModel[i].startingPortNumber = nextLineNumber;

	/*  Depending on the model, set up some config variables */
	switch (dev->device) {
	case PCI_DEVICE_ID_RP4QUAD:
		str = "Quadcable";
		max_num_aiops = 1;
		ports_per_aiop = 4;
		rocketModel[i].model = MODEL_RP4QUAD;
		strcpy(rocketModel[i].modelString, "RocketPort 4 port w/quad cable");
		rocketModel[i].numPorts = 4;
		break;
	case PCI_DEVICE_ID_RP8OCTA:
		str = "Octacable";
		max_num_aiops = 1;
		rocketModel[i].model = MODEL_RP8OCTA;
		strcpy(rocketModel[i].modelString, "RocketPort 8 port w/octa cable");
		rocketModel[i].numPorts = 8;
		break;
	case PCI_DEVICE_ID_URP8OCTA:
		str = "Octacable";
		max_num_aiops = 1;
		rocketModel[i].model = MODEL_UPCI_RP8OCTA;
		strcpy(rocketModel[i].modelString, "RocketPort UPCI 8 port w/octa cable");
		rocketModel[i].numPorts = 8;
		break;
	case PCI_DEVICE_ID_RP8INTF:
		str = "8";
		max_num_aiops = 1;
		rocketModel[i].model = MODEL_RP8INTF;
		strcpy(rocketModel[i].modelString, "RocketPort 8 port w/external I/F");
		rocketModel[i].numPorts = 8;
		break;
	case PCI_DEVICE_ID_URP8INTF:
		str = "8";
		max_num_aiops = 1;
		rocketModel[i].model = MODEL_UPCI_RP8INTF;
		strcpy(rocketModel[i].modelString, "RocketPort UPCI 8 port w/external I/F");
		rocketModel[i].numPorts = 8;
		break;
	case PCI_DEVICE_ID_RP8J:
		str = "8J";
		max_num_aiops = 1;
		rocketModel[i].model = MODEL_RP8J;
		strcpy(rocketModel[i].modelString, "RocketPort 8 port w/RJ11 connectors");
		rocketModel[i].numPorts = 8;
		break;
	case PCI_DEVICE_ID_RP4J: