Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 1146 insertions, 0 deletions

diff --git a/drivers/net/irda/irport.c b/drivers/net/irda/irport.c
new file mode 100644
index 00000000000..5971315f3fa
--- /dev/null
+++ b/drivers/net/irda/irport.c
@@ -0,0 +1,1146 @@
+/*********************************************************************
+ * 
+ * Filename:	  irport.c
+ * Version:	  1.0
+ * Description:   Half duplex serial port SIR driver for IrDA. 
+ * Status:	  Experimental.
+ * Author:	  Dag Brattli <dagb@cs.uit.no>
+ * Created at:	  Sun Aug  3 13:49:59 1997
+ * Modified at:   Fri Jan 28 20:22:38 2000
+ * Modified by:   Dag Brattli <dagb@cs.uit.no>
+ * Sources:	  serial.c by Linus Torvalds 
+ * 
+ *     Copyright (c) 1997, 1998, 1999-2000 Dag Brattli, All Rights Reserved.
+ *     Copyright (c) 2000-2003 Jean Tourrilhes, All Rights Reserved.
+ *     
+ *     This program is free software; you can redistribute it and/or 
+ *     modify it under the terms of the GNU General Public License as 
+ *     published by the Free Software Foundation; either version 2 of 
+ *     the License, or (at your option) any later version.
+ * 
+ *     This program is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *     GNU General Public License for more details.
+ * 
+ *     You should have received a copy of the GNU General Public License 
+ *     along with this program; if not, write to the Free Software 
+ *     Foundation, Inc., 59 Temple Place, Suite 330, Boston, 
+ *     MA 02111-1307 USA
+ *
+ *     This driver is ment to be a small half duplex serial driver to be
+ *     used for IR-chipsets that has a UART (16550) compatibility mode. 
+ *     Eventually it will replace irtty, because of irtty has some 
+ *     problems that is hard to get around when we don't have control
+ *     over the serial driver. This driver may also be used by FIR 
+ *     drivers to handle SIR mode for them.
+ *
+ ********************************************************************/
+
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/ioport.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/skbuff.h>
+#include <linux/serial_reg.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/rtnetlink.h>
+#include <linux/bitops.h>
+
+#include <asm/system.h>
+#include <asm/io.h>
+
+#include <net/irda/irda.h>
+#include <net/irda/wrapper.h>
+#include "irport.h"
+
+#define IO_EXTENT 8
+
+/* 
+ * Currently you'll need to set these values using insmod like this:
+ * insmod irport io=0x3e8 irq=11
+ */
+static unsigned int io[]  = { ~0, ~0, ~0, ~0 };
+static unsigned int irq[] = { 0, 0, 0, 0 };
+
+static unsigned int qos_mtt_bits = 0x03;
+
+static struct irport_cb *dev_self[] = { NULL, NULL, NULL, NULL};
+static char *driver_name = "irport";
+
+static inline void irport_write_wakeup(struct irport_cb *self);
+static inline int  irport_write(int iobase, int fifo_size, __u8 *buf, int len);
+static inline void irport_receive(struct irport_cb *self);
+
+static int  irport_net_ioctl(struct net_device *dev, struct ifreq *rq, 
+			     int cmd);
+static inline int  irport_is_receiving(struct irport_cb *self);
+static int  irport_set_dtr_rts(struct net_device *dev, int dtr, int rts);
+static int  irport_raw_write(struct net_device *dev, __u8 *buf, int len);
+static struct net_device_stats *irport_net_get_stats(struct net_device *dev);
+static int irport_change_speed_complete(struct irda_task *task);
+static void irport_timeout(struct net_device *dev);
+
+static irqreturn_t irport_interrupt(int irq, void *dev_id,
+				    struct pt_regs *regs);
+static int irport_hard_xmit(struct sk_buff *skb, struct net_device *dev);
+static void irport_change_speed(void *priv, __u32 speed);
+static int irport_net_open(struct net_device *dev);
+static int irport_net_close(struct net_device *dev);
+
+static struct irport_cb *
+irport_open(int i, unsigned int iobase, unsigned int irq)
+{
+	struct net_device *dev;
+	struct irport_cb *self;
+
+	IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
+
+	/* Lock the port that we need */
+	if (!request_region(iobase, IO_EXTENT, driver_name)) {
+		IRDA_DEBUG(0, "%s(), can't get iobase of 0x%03x\n",
+			   __FUNCTION__, iobase);
+		goto err_out1;
+	}
+
+	/*
+	 *  Allocate new instance of the driver
+	 */
+	dev = alloc_irdadev(sizeof(struct irport_cb));
+	if (!dev) {
+		IRDA_ERROR("%s(), can't allocate memory for "
+			   "irda device!\n", __FUNCTION__);
+		goto err_out2;
+	}
+
+	self = dev->priv;
+	spin_lock_init(&self->lock);
+
+	/* Need to store self somewhere */
+	dev_self[i] = self;
+	self->priv = self;
+	self->index = i;
+
+	/* Initialize IO */
+	self->io.sir_base  = iobase;
+        self->io.sir_ext   = IO_EXTENT;
+        self->io.irq       = irq;
+        self->io.fifo_size = 16;		/* 16550A and compatible */
+
+	/* Initialize QoS for this device */
+	irda_init_max_qos_capabilies(&self->qos);
+	
+	self->qos.baud_rate.bits = IR_9600|IR_19200|IR_38400|IR_57600|
+		IR_115200;
+
+	self->qos.min_turn_time.bits = qos_mtt_bits;
+	irda_qos_bits_to_value(&self->qos);
+	
+	/* Bootstrap ZeroCopy Rx */
+	self->rx_buff.truesize = IRDA_SKB_MAX_MTU;
+	self->rx_buff.skb = __dev_alloc_skb(self->rx_buff.truesize,
+					    GFP_KERNEL);
+	if (self->rx_buff.skb == NULL) {
+		IRDA_ERROR("%s(), can't allocate memory for "
+			   "receive buffer!\n", __FUNCTION__);
+		goto err_out3;
+	}
+	skb_reserve(self->rx_buff.skb, 1);
+	self->rx_buff.head = self->rx_buff.skb->data;
+	/* No need to memset the buffer, unless you are really pedantic */
+
+	/* Finish setup the Rx buffer descriptor */
+	self->rx_buff.in_frame = FALSE;
+	self->rx_buff.state = OUTSIDE_FRAME;
+	self->rx_buff.data = self->rx_buff.head;
+
+	/* Specify how much memory we want */
+	self->tx_buff.truesize = 4000;
+	
+	/* Allocate memory if needed */
+	if (self->tx_buff.truesize > 0) {
+		self->tx_buff.head = (__u8 *) kmalloc(self->tx_buff.truesize, 
+						      GFP_KERNEL);
+		if (self->tx_buff.head == NULL) {
+			IRDA_ERROR("%s(), can't allocate memory for "
+				   "transmit buffer!\n", __FUNCTION__);
+			goto err_out4;
+		}
+		memset(self->tx_buff.head, 0, self->tx_buff.truesize);
+	}	
+	self->tx_buff.data = self->tx_buff.head;
+
+	self->netdev = dev;
+	/* Keep track of module usage */
+	SET_MODULE_OWNER(dev);
+
+	/* May be overridden by piggyback drivers */
+	self->interrupt    = irport_interrupt;
+	self->change_speed = irport_change_speed;
+
+	/* Override the network functions we need to use */
+	dev->hard_start_xmit = irport_hard_xmit;
+	dev->tx_timeout	     = irport_timeout;
+	dev->watchdog_timeo  = HZ;  /* Allow time enough for speed change */
+	dev->open            = irport_net_open;
+	dev->stop            = irport_net_close;
+	dev->get_stats	     = irport_net_get_stats;
+	dev->do_ioctl        = irport_net_ioctl;
+
+	/* Make ifconfig display some details */
+	dev->base_addr = iobase;
+	dev->irq = irq;
+
+	if (register_netdev(dev)) {
+		IRDA_ERROR("%s(), register_netdev() failed!\n", __FUNCTION__);
+		goto err_out5;
+	}
+	IRDA_MESSAGE("IrDA: Registered device %s (irport io=0x%X irq=%d)\n",
+		dev->name, iobase, irq);
+
+	return self;
+ err_out5:
+	kfree(self->tx_buff.head);
+ err_out4:
+	kfree_skb(self->rx_buff.skb);
+ err_out3:
+	free_netdev(dev);
+	dev_self[i] = NULL;
+ err_out2:
+	release_region(iobase, IO_EXTENT);
+ err_out1:
+	return NULL;
+}
+
+static int irport_close(struct irport_cb *self)
+{
+	IRDA_ASSERT(self != NULL, return -1;);
+
+	/* We are not using any dongle anymore! */
+	if (self->dongle)
+		irda_device_dongle_cleanup(self->dongle);
+	self->dongle = NULL;
+	
+	/* Remove netdevice */
+	unregister_netdev(self->netdev);
+
+	/* Release the IO-port that this driver is using */
+	IRDA_DEBUG(0 , "%s(), Releasing Region %03x\n", 
+		   __FUNCTION__, self->io.sir_base);
+	release_region(self->io.sir_base, self->io.sir_ext);
+
+	if (self->tx_buff.head)
+		kfree(self->tx_buff.head);
+	
+	if (self->rx_buff.skb)
+		kfree_skb(self->rx_buff.skb);
+	self->rx_buff.skb = NULL;
+	
+	/* Remove ourselves */
+	dev_self[self->index] = NULL;
+	free_netdev(self->netdev);
+	
+	return 0;
+}
+
+static void irport_stop(struct irport_cb *self)
+{
+	int iobase;
+
+	iobase = self->io.sir_base;
+
+	/* We can't lock, we may be called from a FIR driver - Jean II */
+
+	/* We are not transmitting any more */
+	self->transmitting = 0;
+
+	/* Reset UART */
+	outb(0, iobase+UART_MCR);
+	
+	/* Turn off interrupts */
+	outb(0, iobase+UART_IER);
+}
+
+static void irport_start(struct irport_cb *self)
+{
+	int iobase;
+
+	iobase = self->io.sir_base;
+
+	irport_stop(self);
+	
+	/* We can't lock, we may be called from a FIR driver - Jean II */
+
+	/* Initialize UART */
+	outb(UART_LCR_WLEN8, iobase+UART_LCR);  /* Reset DLAB */
+	outb((UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2), iobase+UART_MCR);
+	
+	/* Turn on interrups */
+	outb(UART_IER_RLSI | UART_IER_RDI |UART_IER_THRI, iobase+UART_IER);
+}
+
+/*
+ * Function irport_probe (void)
+ *
+ *    Start IO port 
+ *
+ */
+int irport_probe(int iobase)
+{
+	IRDA_DEBUG(4, "%s(), iobase=%#x\n", __FUNCTION__, iobase);
+
+	return 0;
+}
+
+/*
+ * Function irport_get_fcr (speed)
+ *
+ *    Compute value of fcr
+ *
+ */
+static inline unsigned int irport_get_fcr(__u32 speed)
+{
+	unsigned int fcr;    /* FIFO control reg */
+
+	/* Enable fifos */
+	fcr = UART_FCR_ENABLE_FIFO;
+
+	/* 
+	 * Use trigger level 1 to avoid 3 ms. timeout delay at 9600 bps, and
+	 * almost 1,7 ms at 19200 bps. At speeds above that we can just forget
+	 * about this timeout since it will always be fast enough. 
+	 */
+	if (speed < 38400)
+		fcr |= UART_FCR_TRIGGER_1;
+	else 
+		//fcr |= UART_FCR_TRIGGER_14;
+		fcr |= UART_FCR_TRIGGER_8;
+
+	return(fcr);
+}
+ 
+/*
+ * Function irport_change_speed (self, speed)
+ *
+ *    Set speed of IrDA port to specified baudrate
+ *
+ * This function should be called with irq off and spin-lock.
+ */
+static void irport_change_speed(void *priv, __u32 speed)
+{
+	struct irport_cb *self = (struct irport_cb *) priv;
+	int iobase; 
+	unsigned int fcr;    /* FIFO control reg */
+	unsigned int lcr;    /* Line control reg */
+	int divisor;
+
+	IRDA_ASSERT(self != NULL, return;);
+	IRDA_ASSERT(speed != 0, return;);
+
+	IRDA_DEBUG(1, "%s(), Setting speed to: %d - iobase=%#x\n",
+		    __FUNCTION__, speed, self->io.sir_base);
+
+	/* We can't lock, we may be called from a FIR driver - Jean II */
+
+	iobase = self->io.sir_base;
+	
+	/* Update accounting for new speed */
+	self->io.speed = speed;
+
+	/* Turn off interrupts */
+	outb(0, iobase+UART_IER); 
+
+	divisor = SPEED_MAX/speed;
+	
+	/* Get proper fifo configuration */
+	fcr = irport_get_fcr(speed);
+
+	/* IrDA ports use 8N1 */
+	lcr = UART_LCR_WLEN8;
+	
+	outb(UART_LCR_DLAB | lcr, iobase+UART_LCR); /* Set DLAB */
+	outb(divisor & 0xff,      iobase+UART_DLL); /* Set speed */
+	outb(divisor >> 8,	  iobase+UART_DLM);
+	outb(lcr,		  iobase+UART_LCR); /* Set 8N1	*/
+	outb(fcr,		  iobase+UART_FCR); /* Enable FIFO's */
+
+	/* Turn on interrups */
+	/* This will generate a fatal interrupt storm.
+	 * People calling us will do that properly - Jean II */
+	//outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
+}
+
+/*
+ * Function __irport_change_speed (instance, state, param)
+ *
+ *    State machine for changing speed of the device. We do it this way since
+ *    we cannot use schedule_timeout() when we are in interrupt context
+ *
+ */
+int __irport_change_speed(struct irda_task *task)
+{
+	struct irport_cb *self;
+	__u32 speed = (__u32) task->param;
+	unsigned long flags = 0;
+	int wasunlocked = 0;
+	int ret = 0;
+
+	IRDA_DEBUG(2, "%s(), <%ld>\n", __FUNCTION__, jiffies); 
+
+	self = (struct irport_cb *) task->instance;
+
+	IRDA_ASSERT(self != NULL, return -1;);
+
+	/* Locking notes : this function may be called from irq context with
+	 * spinlock, via irport_write_wakeup(), or from non-interrupt without
+	 * spinlock (from the task timer). Yuck !
+	 * This is ugly, and unsafe is the spinlock is not already aquired.
+	 * This will be fixed when irda-task get rewritten.
+	 * Jean II */
+	if (!spin_is_locked(&self->lock)) {
+		spin_lock_irqsave(&self->lock, flags);
+		wasunlocked = 1;
+	}
+
+	switch (task->state) {
+	case IRDA_TASK_INIT:
+	case IRDA_TASK_WAIT:
+		/* Are we ready to change speed yet? */
+		if (self->tx_buff.len > 0) {
+			task->state = IRDA_TASK_WAIT;
+
+			/* Try again later */
+			ret = msecs_to_jiffies(20);
+			break;
+		}
+
+		if (self->dongle)
+			irda_task_next_state(task, IRDA_TASK_CHILD_INIT);
+		else
+			irda_task_next_state(task, IRDA_TASK_CHILD_DONE);
+		break;
+	case IRDA_TASK_CHILD_INIT:
+		/* Go to default speed */
+		self->change_speed(self->priv, 9600);
+
+		/* Change speed of dongle */
+		if (irda_task_execute(self->dongle,
+				      self->dongle->issue->change_speed, 
+				      NULL, task, (void *) speed))
+		{
+			/* Dongle need more time to change its speed */
+			irda_task_next_state(task, IRDA_TASK_CHILD_WAIT);
+
+			/* Give dongle 1 sec to finish */
+			ret = msecs_to_jiffies(1000);
+		} else
+			/* Child finished immediately */
+			irda_task_next_state(task, IRDA_TASK_CHILD_DONE);
+		break;
+	case IRDA_TASK_CHILD_WAIT:
+		IRDA_WARNING("%s(), changing speed of dongle timed out!\n", __FUNCTION__);
+		ret = -1;		
+		break;
+	case IRDA_TASK_CHILD_DONE:
+		/* Finally we are ready to change the speed */
+		self->change_speed(self->priv, speed);
+		
+		irda_task_next_state(task, IRDA_TASK_DONE);
+		break;
+	default:
+		IRDA_ERROR("%s(), unknown state %d\n",
+			   __FUNCTION__, task->state);
+		irda_task_next_state(task, IRDA_TASK_DONE);
+		ret = -1;
+		break;
+	}
+	/* Put stuff in the state we found them - Jean II */
+	if(wasunlocked) {
+		spin_unlock_irqrestore(&self->lock, flags);
+	}
+
+	return ret;
+}
+
+/*
+ * Function irport_change_speed_complete (task)
+ *
+ *    Called when the change speed operation completes
+ *
+ */
+static int irport_change_speed_complete(struct irda_task *task)
+{
+	struct irport_cb *self;
+
+	IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
+
+	self = (struct irport_cb *) task->instance;
+
+	IRDA_ASSERT(self != NULL, return -1;);
+	IRDA_ASSERT(self->netdev != NULL, return -1;);
+
+	/* Finished changing speed, so we are not busy any longer */
+	/* Signal network layer so it can try to send the frame */
+
+	netif_wake_queue(self->netdev);
+	
+	return 0;
+}
+
+/*
+ * Function irport_timeout (struct net_device *dev)
+ *
+ *    The networking layer thinks we timed out.
+ *
+ */
+
+static void irport_timeout(struct net_device *dev)
+{
+	struct irport_cb *self;
+	int iobase;
+	int iir, lsr;
+	unsigned long flags;
+
+	self = (struct irport_cb *) dev->priv;
+	IRDA_ASSERT(self != NULL, return;);
+	iobase = self->io.sir_base;
+	
+	IRDA_WARNING("%s: transmit timed out, jiffies = %ld, trans_start = %ld\n",
+		dev->name, jiffies, dev->trans_start);
+	spin_lock_irqsave(&self->lock, flags);
+
+	/* Debug what's happening... */
+
+	/* Get interrupt status */
+	lsr = inb(iobase+UART_LSR);
+	/* Read interrupt register */
+	iir = inb(iobase+UART_IIR);
+	IRDA_DEBUG(0, "%s(), iir=%02x, lsr=%02x, iobase=%#x\n", 
+		   __FUNCTION__, iir, lsr, iobase);
+
+	IRDA_DEBUG(0, "%s(), transmitting=%d, remain=%d, done=%d\n", 
+		   __FUNCTION__, self->transmitting, self->tx_buff.len,
+		   self->tx_buff.data - self->tx_buff.head);
+
+	/* Now, restart the port */
+	irport_start(self);
+	self->change_speed(self->priv, self->io.speed);
+	/* This will re-enable irqs */
+	outb(/*UART_IER_RLSI|*/UART_IER_RDI/*|UART_IER_THRI*/, iobase+UART_IER);
+	dev->trans_start = jiffies;
+	spin_unlock_irqrestore(&self->lock, flags);
+
+	netif_wake_queue(dev);
+}
+ 
+/*
+ * Function irport_wait_hw_transmitter_finish ()
+ *
+ *    Wait for the real end of HW transmission
+ *
+ * The UART is a strict FIFO, and we get called only when we have finished
+ * pushing data to the FIFO, so the maximum amount of time we must wait
+ * is only for the FIFO to drain out.
+ *
+ * We use a simple calibrated loop. We may need to adjust the loop
+ * delay (udelay) to balance I/O traffic and latency. And we also need to
+ * adjust the maximum timeout.
+ * It would probably be better to wait for the proper interrupt,
+ * but it doesn't seem to be available.
+ *
+ * We can't use jiffies or kernel timers because :
+ * 1) We are called from the interrupt handler, which disable softirqs,
+ * so jiffies won't be increased
+ * 2) Jiffies granularity is usually very coarse (10ms), and we don't
+ * want to wait that long to detect stuck hardware.
+ * Jean II
+ */
+
+static void irport_wait_hw_transmitter_finish(struct irport_cb *self)
+{
+	int iobase;
+	int count = 1000;	/* 1 ms */
+	
+	iobase = self->io.sir_base;
+
+	/* Calibrated busy loop */
+	while((count-- > 0) && !(inb(iobase+UART_LSR) & UART_LSR_TEMT))
+		udelay(1);
+
+	if(count == 0)
+		IRDA_DEBUG(0, "%s(): stuck transmitter\n", __FUNCTION__);
+}
+
+/*
+ * Function irport_hard_start_xmit (struct sk_buff *skb, struct net_device *dev)
+ *
+ *    Transmits the current frame until FIFO is full, then
+ *    waits until the next transmitt interrupt, and continues until the
+ *    frame is transmitted.
+ */
+static int irport_hard_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct irport_cb *self;
+	unsigned long flags;
+	int iobase;
+	s32 speed;
+
+	IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
+
+	IRDA_ASSERT(dev != NULL, return 0;);
+	
+	self = (struct irport_cb *) dev->priv;
+	IRDA_ASSERT(self != NULL, return 0;);
+
+	iobase = self->io.sir_base;
+
+	netif_stop_queue(dev);
+
+	/* Make sure tests & speed change are atomic */
+	spin_lock_irqsave(&self->lock, flags);
+
+	/* Check if we need to change the speed */
+	speed = irda_get_next_speed(skb);
+	if ((speed != self->io.speed) && (speed != -1)) {
+		/* Check for empty frame */
+		if (!skb->len) {
+			/*
+			 * We send frames one by one in SIR mode (no
+			 * pipelining), so at this point, if we were sending
+			 * a previous frame, we just received the interrupt
+			 * telling us it is finished (UART_IIR_THRI).
+			 * Therefore, waiting for the transmitter to really
+			 * finish draining the fifo won't take too long.
+			 * And the interrupt handler is not expected to run.
+			 * - Jean II */
+			irport_wait_hw_transmitter_finish(self);
+			/* Better go there already locked - Jean II */
+			irda_task_execute(self, __irport_change_speed, 
+					  irport_change_speed_complete, 
+					  NULL, (void *) speed);
+			dev->trans_start = jiffies;
+			spin_unlock_irqrestore(&self->lock, flags);
+			dev_kfree_skb(skb);
+			return 0;
+		} else
+			self->new_speed = speed;
+	}
+
+	/* Init tx buffer */
+	self->tx_buff.data = self->tx_buff.head;
+
+        /* Copy skb to tx_buff while wrapping, stuffing and making CRC */
+	self->tx_buff.len = async_wrap_skb(skb, self->tx_buff.data, 
+					   self->tx_buff.truesize);
+	
+	self->stats.tx_bytes += self->tx_buff.len;
+
+	/* We are transmitting */
+	self->transmitting = 1;
+
+	/* Turn on transmit finished interrupt. Will fire immediately!  */
+	outb(UART_IER_THRI, iobase+UART_IER); 
+
+	dev->trans_start = jiffies;
+	spin_unlock_irqrestore(&self->lock, flags);
+
+	dev_kfree_skb(skb);
+	
+	return 0;
+}
+        
+/*
+ * Function irport_write (driver)
+ *
+ *    Fill Tx FIFO with transmit data
+ *
+ * Called only from irport_write_wakeup()
+ */
+static inline int irport_write(int iobase, int fifo_size, __u8 *buf, int len)
+{
+	int actual = 0;
+
+	/* Fill FIFO with current frame */
+	while ((actual < fifo_size) && (actual < len)) {
+		/* Transmit next byte */
+		outb(buf[actual], iobase+UART_TX);
+
+		actual++;
+	}
+        
+	return actual;
+}
+
+/*
+ * Function irport_write_wakeup (tty)
+ *
+ *    Called by the driver when there's room for more data.  If we have
+ *    more packets to send, we send them here.
+ *
+ * Called only from irport_interrupt()
+ * Make sure this function is *not* called while we are receiving,
+ * otherwise we will reset fifo and loose data :-(
+ */
+static inline void irport_write_wakeup(struct irport_cb *self)
+{
+	int actual = 0;
+	int iobase;
+	unsigned int fcr;
+
+	IRDA_ASSERT(self != NULL, return;);
+
+	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+	iobase = self->io.sir_base;
+
+	/* Finished with frame?  */
+	if (self->tx_buff.len > 0)  {
+		/* Write data left in transmit buffer */
+		actual = irport_write(iobase, self->io.fifo_size, 
+				      self->tx_buff.data, self->tx_buff.len);
+		self->tx_buff.data += actual;
+		self->tx_buff.len  -= actual;
+	} else {
+		/* 
+		 *  Now serial buffer is almost free & we can start 
+		 *  transmission of another packet. But first we must check
+		 *  if we need to change the speed of the hardware
+		 */
+		if (self->new_speed) {
+			irport_wait_hw_transmitter_finish(self);
+			irda_task_execute(self, __irport_change_speed, 
+					  irport_change_speed_complete, 
+					  NULL, (void *) self->new_speed);
+			self->new_speed = 0;
+		} else {
+			/* Tell network layer that we want more frames */
+			netif_wake_queue(self->netdev);
+		}
+		self->stats.tx_packets++;
+
+		/* 
+		 * Reset Rx FIFO to make sure that all reflected transmit data
+		 * is discarded. This is needed for half duplex operation
+		 */
+		fcr = irport_get_fcr(self->io.speed);
+		fcr |= UART_FCR_CLEAR_RCVR;
+		outb(fcr, iobase+UART_FCR);
+
+		/* Finished transmitting */
+		self->transmitting = 0;
+
+		/* Turn on receive interrupts */
+		outb(UART_IER_RDI, iobase+UART_IER);
+
+		IRDA_DEBUG(1, "%s() : finished Tx\n", __FUNCTION__);
+	}
+}
+
+/*
+ * Function irport_receive (self)
+ *
+ *    Receive one frame from the infrared port
+ *
+ * Called only from irport_interrupt()
+ */
+static inline void irport_receive(struct irport_cb *self) 
+{
+	int boguscount = 0;
+	int iobase;
+
+	IRDA_ASSERT(self != NULL, return;);
+
+	iobase = self->io.sir_base;
+
+	/*  
+	 * Receive all characters in Rx FIFO, unwrap and unstuff them. 
+         * async_unwrap_char will deliver all found frames  
+	 */
+	do {
+		async_unwrap_char(self->netdev, &self->stats, &self->rx_buff, 
+				  inb(iobase+UART_RX));
+
+		/* Make sure we don't stay here too long */
+		if (boguscount++ > 32) {
+			IRDA_DEBUG(2,"%s(), breaking!\n", __FUNCTION__);
+			break;
+		}
+	} while (inb(iobase+UART_LSR) & UART_LSR_DR);	
+}
+
+/*
+ * Function irport_interrupt (irq, dev_id, regs)
+ *
+ *    Interrupt handler
+ */
+static irqreturn_t irport_interrupt(int irq, void *dev_id,
+				    struct pt_regs *regs) 
+{
+	struct net_device *dev = (struct net_device *) dev_id;
+	struct irport_cb *self;
+	int boguscount = 0;
+	int iobase;
+	int iir, lsr;
+	int handled = 0;
+
+	if (!dev) {
+		IRDA_WARNING("%s() irq %d for unknown device.\n", __FUNCTION__, irq);
+		return IRQ_NONE;
+	}
+	self = (struct irport_cb *) dev->priv;
+
+	spin_lock(&self->lock);
+
+	iobase = self->io.sir_base;
+
+	/* Cut'n'paste interrupt routine from serial.c
+	 * This version try to minimise latency and I/O operations.
+	 * Simplified and modified to enforce half duplex operation.
+	 * - Jean II */
+
+	/* Check status even is iir reg is cleared, more robust and
+	 * eliminate a read on the I/O bus - Jean II */
+	do {
+		/* Get interrupt status ; Clear interrupt */
+		lsr = inb(iobase+UART_LSR);
+		
+		/* Are we receiving or transmitting ? */
+		if(!self->transmitting) {
+			/* Received something ? */
+			if (lsr & UART_LSR_DR)
+				irport_receive(self);
+		} else {
+			/* Room in Tx fifo ? */
+			if (lsr & (UART_LSR_THRE | UART_LSR_TEMT))
+				irport_write_wakeup(self);
+		}
+
+		/* A bit hackish, but working as expected... Jean II */
+		if(lsr & (UART_LSR_THRE | UART_LSR_TEMT | UART_LSR_DR))
+			handled = 1;
+
+		/* Make sure we don't stay here to long */
+		if (boguscount++ > 10) {
+			IRDA_WARNING("%s() irq handler looping : lsr=%02x\n",
+				     __FUNCTION__, lsr);
+			break;
+		}
+
+		/* Read interrupt register */
+ 	        iir = inb(iobase+UART_IIR);
+
+		/* Enable this debug only when no other options and at low
+		 * bit rates, otherwise it may cause Rx overruns (lsr=63).
+		 * - Jean II */
+		IRDA_DEBUG(6, "%s(), iir=%02x, lsr=%02x, iobase=%#x\n", 
+			    __FUNCTION__, iir, lsr, iobase);
+
+		/* As long as interrupt pending... */
+	} while ((iir & UART_IIR_NO_INT) == 0);
+
+	spin_unlock(&self->lock);
+	return IRQ_RETVAL(handled);
+}
+
+/*
+ * Function irport_net_open (dev)
+ *
+ *    Network device is taken up. Usually this is done by "ifconfig irda0 up" 
+ *   
+ */
+static int irport_net_open(struct net_device *dev)
+{
+	struct irport_cb *self;
+	int iobase;
+	char hwname[16];
+	unsigned long flags;
+
+	IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
+
+	IRDA_ASSERT(dev != NULL, return -1;);
+	self = (struct irport_cb *) dev->priv;
+
+	iobase = self->io.sir_base;
+
+	if (request_irq(self->io.irq, self->interrupt, 0, dev->name, 
+			(void *) dev)) {
+		IRDA_DEBUG(0, "%s(), unable to allocate irq=%d\n",
+			   __FUNCTION__, self->io.irq);
+		return -EAGAIN;
+	}
+
+	spin_lock_irqsave(&self->lock, flags);
+	/* Init uart */
+	irport_start(self);
+	/* Set 9600 bauds per default, including at the dongle */
+	irda_task_execute(self, __irport_change_speed, 
+			  irport_change_speed_complete, 
+			  NULL, (void *) 9600);
+	spin_unlock_irqrestore(&self->lock, flags);
+
+
+	/* Give self a hardware name */
+	sprintf(hwname, "SIR @ 0x%03x", self->io.sir_base);
+
+	/* 
+	 * Open new IrLAP layer instance, now that everything should be
+	 * initialized properly 
+	 */
+	self->irlap = irlap_open(dev, &self->qos, hwname);
+
+	/* Ready to play! */
+
+	netif_start_queue(dev);
+
+	return 0;
+}
+
+/*
+ * Function irport_net_close (self)
+ *
+ *    Network device is taken down. Usually this is done by 
+ *    "ifconfig irda0 down" 
+ */
+static int irport_net_close(struct net_device *dev)
+{
+	struct irport_cb *self;
+	int iobase;
+	unsigned long flags;
+
+	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
+
+	IRDA_ASSERT(dev != NULL, return -1;);
+	self = (struct irport_cb *) dev->priv;
+
+	IRDA_ASSERT(self != NULL, return -1;);
+
+	iobase = self->io.sir_base;
+
+	/* Stop device */
+	netif_stop_queue(dev);
+	
+	/* Stop and remove instance of IrLAP */
+	if (self->irlap)
+		irlap_close(self->irlap);
+	self->irlap = NULL;
+
+	spin_lock_irqsave(&self->lock, flags);
+	irport_stop(self);
+	spin_unlock_irqrestore(&self->lock, flags);
+
+	free_irq(self->io.irq, dev);
+
+	return 0;
+}
+
+/*
+ * Function irport_is_receiving (self)
+ *
+ *    Returns true is we are currently receiving data
+ *
+ */
+static inline int irport_is_receiving(struct irport_cb *self)
+{
+	return (self->rx_buff.state != OUTSIDE_FRAME);
+}
+
+/*
+ * Function irport_set_dtr_rts (tty, dtr, rts)
+ *
+ *    This function can be used by dongles etc. to set or reset the status
+ *    of the dtr and rts lines
+ */
+static int irport_set_dtr_rts(struct net_device *dev, int dtr, int rts)
+{
+	struct irport_cb *self = dev->priv;
+	int iobase;
+
+	IRDA_ASSERT(self != NULL, return -1;);
+
+	iobase = self->io.sir_base;
+
+	if (dtr)
+		dtr = UART_MCR_DTR;
+	if (rts)
+		rts = UART_MCR_RTS;
+
+	outb(dtr|rts|UART_MCR_OUT2, iobase+UART_MCR);
+
+	return 0;
+}
+
+static int irport_raw_write(struct net_device *dev, __u8 *buf, int len)
+{
+	struct irport_cb *self = (struct irport_cb *) dev->priv;
+	int actual = 0;
+	int iobase;
+
+	IRDA_ASSERT(self != NULL, return -1;);
+
+	iobase = self->io.sir_base;
+
+	/* Tx FIFO should be empty! */
+	if (!(inb(iobase+UART_LSR) & UART_LSR_THRE)) {
+		IRDA_DEBUG( 0, "%s(), failed, fifo not empty!\n", __FUNCTION__);
+		return -1;
+	}
+        
+	/* Fill FIFO with current frame */
+	while (actual < len) {
+		/* Transmit next byte */
+		outb(buf[actual], iobase+UART_TX);
+		actual++;
+	}
+
+	return actual;
+}
+
+/*
+ * Function irport_net_ioctl (dev, rq, cmd)
+ *
+ *    Process IOCTL commands for this device
+ *
+ */
+static int irport_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
+{
+	struct if_irda_req *irq = (struct if_irda_req *) rq;
+	struct irport_cb *self;
+	dongle_t *dongle;
+	unsigned long flags;
+	int ret = 0;
+
+	IRDA_ASSERT(dev != NULL, return -1;);
+
+	self = dev->priv;
+
+	IRDA_ASSERT(self != NULL, return -1;);
+
+	IRDA_DEBUG(2, "%s(), %s, (cmd=0x%X)\n", __FUNCTION__, dev->name, cmd);
+	
+	switch (cmd) {
+	case SIOCSBANDWIDTH: /* Set bandwidth */
+		if (!capable(CAP_NET_ADMIN))
+			ret = -EPERM;
+                else
+			irda_task_execute(self, __irport_change_speed, NULL, 
+					  NULL, (void *) irq->ifr_baudrate);
+		break;
+	case SIOCSDONGLE: /* Set dongle */
+		if (!capable(CAP_NET_ADMIN)) {
+			ret = -EPERM;
+			break;
+		}
+
+		/* Locking :
+		 * irda_device_dongle_init() can't be locked.
+		 * irda_task_execute() doesn't need to be locked.
+		 * Jean II
+		 */
+
+		/* Initialize dongle */
+		dongle = irda_device_dongle_init(dev, irq->ifr_dongle);
+		if (!dongle)
+			break;
+		
+		dongle->set_mode    = NULL;
+		dongle->read        = NULL;
+		dongle->write       = irport_raw_write;
+		dongle->set_dtr_rts = irport_set_dtr_rts;
+		
+		/* Now initialize the dongle!  */
+		dongle->issue->open(dongle, &self->qos);
+		
+		/* Reset dongle */
+		irda_task_execute(dongle, dongle->issue->reset, NULL, NULL, 
+				  NULL);	
+
+		/* Make dongle available to driver only now to avoid
+		 * race conditions - Jean II */
+		self->dongle = dongle;
+		break;
+	case SIOCSMEDIABUSY: /* Set media busy */
+		if (!capable(CAP_NET_ADMIN)) {
+			ret = -EPERM;
+			break;
+		}
+
+		irda_device_set_media_busy(self->netdev, TRUE);
+		break;
+	case SIOCGRECEIVING: /* Check if we are receiving right now */
+		irq->ifr_receiving = irport_is_receiving(self);
+		break;
+	case SIOCSDTRRTS:
+		if (!capable(CAP_NET_ADMIN)) {
+			ret = -EPERM;
+			break;
+		}
+
+		/* No real need to lock... */
+		spin_lock_irqsave(&self->lock, flags);
+		irport_set_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
+		spin_unlock_irqrestore(&self->lock, flags);
+		break;
+	default:
+		ret = -EOPNOTSUPP;
+	}
+	
+	return ret;
+}
+
+static struct net_device_stats *irport_net_get_stats(struct net_device *dev)
+{
+	struct irport_cb *self = (struct irport_cb *) dev->priv;
+	
+	return &self->stats;
+}
+
+static int __init irport_init(void)
+{
+ 	int i;
+
+ 	for (i=0; (io[i] < 2000) && (i < 4); i++) {
+ 		if (irport_open(i, io[i], irq[i]) != NULL)
+ 			return 0;
+ 	}
+	/* 
+	 * Maybe something failed, but we can still be usable for FIR drivers 
+	 */
+ 	return 0;
+}
+
+/*
+ * Function irport_cleanup ()
+ *
+ *    Close all configured ports
+ *
+ */
+static void __exit irport_cleanup(void)
+{
+ 	int i;
+
+        IRDA_DEBUG( 4, "%s()\n", __FUNCTION__);
+
+	for (i=0; i < 4; i++) {
+ 		if (dev_self[i])
+ 			irport_close(dev_self[i]);
+ 	}
+}
+
+MODULE_PARM(io, "1-4i");
+MODULE_PARM_DESC(io, "Base I/O addresses");
+MODULE_PARM(irq, "1-4i");
+MODULE_PARM_DESC(irq, "IRQ lines");
+
+MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
+MODULE_DESCRIPTION("Half duplex serial driver for IrDA SIR mode");
+MODULE_LICENSE("GPL");
+
+module_init(irport_init);
+module_exit(irport_cleanup);
+