irport.c

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		/* 
		 * Reset Rx FIFO to make sure that all reflected transmit data
		 * is discarded. This is needed for half duplex operation
		 */
		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR;
		if (self->io.speed < 38400)
			fcr |= UART_FCR_TRIGGER_1;
		else 
			fcr |= UART_FCR_TRIGGER_14;

		outb(fcr, iobase+UART_FCR);

		/* Turn on receive interrupts */
		outb(UART_IER_RDI, iobase+UART_IER);
	}
}

/*
 * Function irport_write (driver)
 *
 *    Fill Tx FIFO with transmit data
 *
 */
static int irport_write(int iobase, int fifo_size, __u8 *buf, int len)
{
	int actual = 0;

	/* Tx FIFO should be empty! */
	if (!(inb(iobase+UART_LSR) & UART_LSR_THRE)) {
		IRDA_DEBUG(0, __FUNCTION__ "(), failed, fifo not empty!\n");
		return 0;
	}
        
	/* Fill FIFO with current frame */
	while ((fifo_size-- > 0) && (actual < len)) {
		/* Transmit next byte */
		outb(buf[actual], iobase+UART_TX);

		actual++;
	}
        
	return actual;
}

/*
 * 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(0, __FUNCTION__ "()\n");

	self = (struct irport_cb *) task->instance;

	ASSERT(self != NULL, return -1;);
	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;

	self = (struct irport_cb *) dev->priv;
	iobase = self->io.sir_base;
	
	WARNING("%s: transmit timed out\n", dev->name);
	irport_start(self);
	self->change_speed(self->priv, self->io.speed);
	dev->trans_start = jiffies;
	netif_wake_queue(dev);
}
 
/*
 * 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 transmited.
 */
int irport_hard_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct irport_cb *self;
	unsigned long flags;
	int iobase;
	__u32 speed;

	ASSERT(dev != NULL, return 0;);
	
	self = (struct irport_cb *) dev->priv;
	ASSERT(self != NULL, return 0;);

	iobase = self->io.sir_base;

	netif_stop_queue(dev);
	
	/* Check if we need to change the speed */
	if ((speed = irda_get_speed(skb)) != self->io.speed) {
		/* Check for empty frame */
		if (!skb->len) {
			irda_task_execute(self, __irport_change_speed, 
					  irport_change_speed_complete, 
					  NULL, (void *) speed);
			return 0;
		} else
			self->new_speed = speed;
	}

	spin_lock_irqsave(&self->lock, flags);

	/* 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;

	/* Turn on transmit finished interrupt. Will fire immediately!  */
	outb(UART_IER_THRI, iobase+UART_IER); 

	spin_unlock_irqrestore(&self->lock, flags);

	dev_kfree_skb(skb);
	
	return 0;
}
        
/*
 * Function irport_receive (self)
 *
 *    Receive one frame from the infrared port
 *
 */
static void irport_receive(struct irport_cb *self) 
{
	int boguscount = 0;
	int iobase;

	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 to long */
		if (boguscount++ > 32) {
			IRDA_DEBUG(2,__FUNCTION__ "(), breaking!\n");
			break;
		}
	} while (inb(iobase+UART_LSR) & UART_LSR_DR);	
}

/*
 * Function irport_interrupt (irq, dev_id, regs)
 *
 *    Interrupt handler
 */
void 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;

	if (!dev) {
		WARNING(__FUNCTION__ "() irq %d for unknown device.\n", irq);
		return;
	}
	self = (struct irport_cb *) dev->priv;

	spin_lock(&self->lock);

	iobase = self->io.sir_base;

	iir = inb(iobase+UART_IIR) & UART_IIR_ID;
	while (iir) {
		/* Clear interrupt */
		lsr = inb(iobase+UART_LSR);

		IRDA_DEBUG(4, __FUNCTION__ 
			   "(), iir=%02x, lsr=%02x, iobase=%#x\n", 
			   iir, lsr, iobase);

		switch (iir) {
		case UART_IIR_RLSI:
			IRDA_DEBUG(2, __FUNCTION__ "(), RLSI\n");
			break;
		case UART_IIR_RDI:
			/* Receive interrupt */
			irport_receive(self);
			break;
		case UART_IIR_THRI:
			if (lsr & UART_LSR_THRE)
				/* Transmitter ready for data */
				irport_write_wakeup(self);
			break;
		default:
			IRDA_DEBUG(0, __FUNCTION__ "(), unhandled IIR=%#x\n", iir);
			break;
		} 
		
		/* Make sure we don't stay here to long */
		if (boguscount++ > 100)
			break;

 	        iir = inb(iobase + UART_IIR) & UART_IIR_ID;
	}
	spin_unlock(&self->lock);
}

static int irport_net_init(struct net_device *dev)
{
	/* Set up to be a normal IrDA network device driver */
	irda_device_setup(dev);

	/* Insert overrides below this line! */

	return 0;
}

/*
 * Function irport_net_open (dev)
 *
 *    Network device is taken up. Usually this is done by "ifconfig irda0 up" 
 *   
 */
int irport_net_open(struct net_device *dev)
{
	struct irport_cb *self;
	int iobase;

	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))
		return -EAGAIN;

	irport_start(self);


	/* 
	 * Open new IrLAP layer instance, now that everything should be
	 * initialized properly 
	 */
	self->irlap = irlap_open(dev, &self->qos);

	/* FIXME: change speed of dongle */
	/* Ready to play! */

	netif_start_queue(dev);
	
	MOD_INC_USE_COUNT;

	return 0;
}

/*
 * Function irport_net_close (self)
 *
 *    Network device is taken down. Usually this is done by 
 *    "ifconfig irda0 down" 
 */
int irport_net_close(struct net_device *dev)
{
	struct irport_cb *self;
	int iobase;

	IRDA_DEBUG(4, __FUNCTION__ "()\n");

	ASSERT(dev != NULL, return -1;);
	self = (struct irport_cb *) dev->priv;

	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;

	irport_stop(self);

	free_irq(self->io.irq, dev);

	MOD_DEC_USE_COUNT;

	return 0;
}

/*
 * Function irport_wait_until_sent (self)
 *
 *    Delay exectution until finished transmitting
 *
 */
#if 0
void irport_wait_until_sent(struct irport_cb *self)
{
	int iobase;

	iobase = self->io.sir_base;

	/* Wait until Tx FIFO is empty */
	while (!(inb(iobase+UART_LSR) & UART_LSR_THRE)) {
		IRDA_DEBUG(2, __FUNCTION__ "(), waiting!\n");
		current->state = TASK_INTERRUPTIBLE;
		schedule_timeout(MSECS_TO_JIFFIES(60));
	}
}
#endif

/*
 * Function irport_is_receiving (self)
 *
 *    Returns true is we are currently receiving data
 *
 */
static 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;

	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;

	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, __FUNCTION__ "(), failed, fifo not empty!\n");
		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;

	ASSERT(dev != NULL, return -1;);

	self = dev->priv;

	ASSERT(self != NULL, return -1;);

	IRDA_DEBUG(2, __FUNCTION__ "(), %s, (cmd=0x%X)\n", dev->name, cmd);
	
	/* Disable interrupts & save flags */
	save_flags(flags);
	cli();
	
	switch (cmd) {
	case SIOCSBANDWIDTH: /* Set bandwidth */
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		irda_task_execute(self, __irport_change_speed, NULL, NULL, 
				  (void *) irq->ifr_baudrate);
		break;
	case SIOCSDONGLE: /* Set dongle */
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		/* 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;
		
		self->dongle = dongle;

		/* Now initialize the dongle!  */
		dongle->issue->open(dongle, &self->qos);
		
		/* Reset dongle */
		irda_task_execute(dongle, dongle->issue->reset, NULL, NULL, 
				  NULL);	
		break;
	case SIOCSMEDIABUSY: /* Set media busy */
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		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))
			return -EPERM;
		irport_set_dtr_rts(dev, irq->ifr_dtr, irq->ifr_rts);
		break;
	default:
		ret = -EOPNOTSUPP;
	}
	
	restore_flags(flags);
	
	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;
}

#ifdef MODULE
MODULE_PARM(io, "1-4i");
MODULE_PARM_DESC(io, "Base I/O adresses");
MODULE_PARM(irq, "1-4i");
MODULE_PARM_DESC(irq, "IRQ lines");

MODULE_AUTHOR("Dag Brattli <[e-mail]>");
MODULE_DESCRIPTION("Half duplex serial driver for IrDA SIR mode");

void cleanup_module(void)
{
	irport_cleanup();
}

int init_module(void)
{
	return irport_init();
}
#endif /* MODULE */