nsc-ircc.c

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				self->stats.rx_fifo_errors++;
		} else {
			/*  
			 * First we must make sure that the frame we
			 * want to deliver is all in main memory. If we
			 * cannot tell, then we check if the Rx FIFO is
			 * empty. If not then we will have to take a nap
			 * and try again later.  
			 */
			if (st_fifo->pending_bytes < self->io.fifo_size) {
				switch_bank(iobase, BANK0);
				if (inb(iobase+LSR) & LSR_RXDA) {
					/* Put this entry back in fifo */
					st_fifo->head--;
					st_fifo->len++;
					st_fifo->pending_bytes += len;
					st_fifo->entries[st_fifo->head].status = status;
					st_fifo->entries[st_fifo->head].len = len;
					/*  
					 * DMA not finished yet, so try again 
					 * later, set timer value, resolution 
					 * 125 us 
					 */
					switch_bank(iobase, BANK4);
					outb(0x02, iobase+TMRL); /* x 125 us */
					outb(0x00, iobase+TMRH);

					/* Start timer */
					outb(IRCR1_TMR_EN, iobase+IRCR1);

					/* Restore bank register */
					outb(bank, iobase+BSR);
					
					return FALSE; /* I'll be back! */
				}
			}

			/* 
			 * Remember the time we received this frame, so we can
			 * reduce the min turn time a bit since we will know
			 * how much time we have used for protocol processing
			 */
			do_gettimeofday(&self->stamp);

			skb = dev_alloc_skb(len+1);
			if (skb == NULL)  {
				IRDA_WARNING("%s(), memory squeeze, "
					     "dropping frame.\n",
					     __FUNCTION__);
				self->stats.rx_dropped++;

				/* Restore bank register */
				outb(bank, iobase+BSR);

				return FALSE;
			}
			
			/* Make sure IP header gets aligned */
			skb_reserve(skb, 1); 

			/* Copy frame without CRC */
			if (self->io.speed < 4000000) {
				skb_put(skb, len-2);
				skb_copy_to_linear_data(skb,
							self->rx_buff.data,
							len - 2);
			} else {
				skb_put(skb, len-4);
				skb_copy_to_linear_data(skb,
							self->rx_buff.data,
							len - 4);
			}

			/* Move to next frame */
			self->rx_buff.data += len;
			self->stats.rx_bytes += len;
			self->stats.rx_packets++;

			skb->dev = self->netdev;
			skb_reset_mac_header(skb);
			skb->protocol = htons(ETH_P_IRDA);
			netif_rx(skb);
			self->netdev->last_rx = jiffies;
		}
	}
	/* Restore bank register */
	outb(bank, iobase+BSR);

	return TRUE;
}

/*
 * Function nsc_ircc_pio_receive (self)
 *
 *    Receive all data in receiver FIFO
 *
 */
static void nsc_ircc_pio_receive(struct nsc_ircc_cb *self) 
{
	__u8 byte;
	int iobase;

	iobase = self->io.fir_base;
	
	/*  Receive all characters in Rx FIFO */
	do {
		byte = inb(iobase+RXD);
		async_unwrap_char(self->netdev, &self->stats, &self->rx_buff, 
				  byte);
	} while (inb(iobase+LSR) & LSR_RXDA); /* Data available */	
}

/*
 * Function nsc_ircc_sir_interrupt (self, eir)
 *
 *    Handle SIR interrupt
 *
 */
static void nsc_ircc_sir_interrupt(struct nsc_ircc_cb *self, int eir)
{
	int actual;

	/* Check if transmit FIFO is low on data */
	if (eir & EIR_TXLDL_EV) {
		/* Write data left in transmit buffer */
		actual = nsc_ircc_pio_write(self->io.fir_base, 
					   self->tx_buff.data, 
					   self->tx_buff.len, 
					   self->io.fifo_size);
		self->tx_buff.data += actual;
		self->tx_buff.len  -= actual;
		
		self->io.direction = IO_XMIT;

		/* Check if finished */
		if (self->tx_buff.len > 0)
			self->ier = IER_TXLDL_IE;
		else { 

			self->stats.tx_packets++;
			netif_wake_queue(self->netdev);
			self->ier = IER_TXEMP_IE;
		}
			
	}
	/* Check if transmission has completed */
	if (eir & EIR_TXEMP_EV) {
		/* Turn around and get ready to receive some data */
		self->io.direction = IO_RECV;
		self->ier = IER_RXHDL_IE;
		/* Check if we need to change the speed?
		 * Need to be after self->io.direction to avoid race with
		 * nsc_ircc_hard_xmit_sir() - Jean II */
		if (self->new_speed) {
			IRDA_DEBUG(2, "%s(), Changing speed!\n", __FUNCTION__);
			self->ier = nsc_ircc_change_speed(self,
							  self->new_speed);
			self->new_speed = 0;
			netif_wake_queue(self->netdev);

			/* Check if we are going to FIR */
			if (self->io.speed > 115200) {
				/* No need to do anymore SIR stuff */
				return;
			}
		}
	}

	/* Rx FIFO threshold or timeout */
	if (eir & EIR_RXHDL_EV) {
		nsc_ircc_pio_receive(self);

		/* Keep receiving */
		self->ier = IER_RXHDL_IE;
	}
}

/*
 * Function nsc_ircc_fir_interrupt (self, eir)
 *
 *    Handle MIR/FIR interrupt
 *
 */
static void nsc_ircc_fir_interrupt(struct nsc_ircc_cb *self, int iobase, 
				   int eir)
{
	__u8 bank;

	bank = inb(iobase+BSR);
	
	/* Status FIFO event*/
	if (eir & EIR_SFIF_EV) {
		/* Check if DMA has finished */
		if (nsc_ircc_dma_receive_complete(self, iobase)) {
			/* Wait for next status FIFO interrupt */
			self->ier = IER_SFIF_IE;
		} else {
			self->ier = IER_SFIF_IE | IER_TMR_IE;
		}
	} else if (eir & EIR_TMR_EV) { /* Timer finished */
		/* Disable timer */
		switch_bank(iobase, BANK4);
		outb(0, iobase+IRCR1);

		/* Clear timer event */
		switch_bank(iobase, BANK0);
		outb(ASCR_CTE, iobase+ASCR);

		/* Check if this is a Tx timer interrupt */
		if (self->io.direction == IO_XMIT) {
			nsc_ircc_dma_xmit(self, iobase);

			/* Interrupt on DMA */
			self->ier = IER_DMA_IE;
		} else {
			/* Check (again) if DMA has finished */
			if (nsc_ircc_dma_receive_complete(self, iobase)) {
				self->ier = IER_SFIF_IE;
			} else {
				self->ier = IER_SFIF_IE | IER_TMR_IE;
			}
		}
	} else if (eir & EIR_DMA_EV) {
		/* Finished with all transmissions? */
		if (nsc_ircc_dma_xmit_complete(self)) {
			if(self->new_speed != 0) {
				/* As we stop the Tx queue, the speed change
				 * need to be done when the Tx fifo is
				 * empty. Ask for a Tx done interrupt */
				self->ier = IER_TXEMP_IE;
			} else {
				/* Check if there are more frames to be
				 * transmitted */
				if (irda_device_txqueue_empty(self->netdev)) {
					/* Prepare for receive */
					nsc_ircc_dma_receive(self);
					self->ier = IER_SFIF_IE;
				} else
					IRDA_WARNING("%s(), potential "
						     "Tx queue lockup !\n",
						     __FUNCTION__);
			}
		} else {
			/*  Not finished yet, so interrupt on DMA again */
			self->ier = IER_DMA_IE;
		}
	} else if (eir & EIR_TXEMP_EV) {
		/* The Tx FIFO has totally drained out, so now we can change
		 * the speed... - Jean II */
		self->ier = nsc_ircc_change_speed(self, self->new_speed);
		self->new_speed = 0;
		netif_wake_queue(self->netdev);
		/* Note : nsc_ircc_change_speed() restarted Rx fifo */
	}

	outb(bank, iobase+BSR);
}

/*
 * Function nsc_ircc_interrupt (irq, dev_id, regs)
 *
 *    An interrupt from the chip has arrived. Time to do some work
 *
 */
static irqreturn_t nsc_ircc_interrupt(int irq, void *dev_id)
{
	struct net_device *dev = dev_id;
	struct nsc_ircc_cb *self;
	__u8 bsr, eir;
	int iobase;

	self = dev->priv;

	spin_lock(&self->lock);	

	iobase = self->io.fir_base;

	bsr = inb(iobase+BSR); 	/* Save current bank */

	switch_bank(iobase, BANK0);	
	self->ier = inb(iobase+IER); 
	eir = inb(iobase+EIR) & self->ier; /* Mask out the interesting ones */ 

	outb(0, iobase+IER); /* Disable interrupts */
	
	if (eir) {
		/* Dispatch interrupt handler for the current speed */
		if (self->io.speed > 115200)
			nsc_ircc_fir_interrupt(self, iobase, eir);
		else
			nsc_ircc_sir_interrupt(self, eir);
	}
	
	outb(self->ier, iobase+IER); /* Restore interrupts */
	outb(bsr, iobase+BSR);       /* Restore bank register */

	spin_unlock(&self->lock);
	return IRQ_RETVAL(eir);
}

/*
 * Function nsc_ircc_is_receiving (self)
 *
 *    Return TRUE is we are currently receiving a frame
 *
 */
static int nsc_ircc_is_receiving(struct nsc_ircc_cb *self)
{
	unsigned long flags;
	int status = FALSE;
	int iobase;
	__u8 bank;

	IRDA_ASSERT(self != NULL, return FALSE;);

	spin_lock_irqsave(&self->lock, flags);

	if (self->io.speed > 115200) {
		iobase = self->io.fir_base;

		/* Check if rx FIFO is not empty */
		bank = inb(iobase+BSR);
		switch_bank(iobase, BANK2);
		if ((inb(iobase+RXFLV) & 0x3f) != 0) {
			/* We are receiving something */
			status =  TRUE;
		}
		outb(bank, iobase+BSR);
	} else 
		status = (self->rx_buff.state != OUTSIDE_FRAME);
	
	spin_unlock_irqrestore(&self->lock, flags);

	return status;
}

/*
 * Function nsc_ircc_net_open (dev)
 *
 *    Start the device
 *
 */
static int nsc_ircc_net_open(struct net_device *dev)
{
	struct nsc_ircc_cb *self;
	int iobase;
	char hwname[32];
	__u8 bank;
	
	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
	
	IRDA_ASSERT(dev != NULL, return -1;);
	self = (struct nsc_ircc_cb *) dev->priv;
	
	IRDA_ASSERT(self != NULL, return 0;);
	
	iobase = self->io.fir_base;
	
	if (request_irq(self->io.irq, nsc_ircc_interrupt, 0, dev->name, dev)) {
		IRDA_WARNING("%s, unable to allocate irq=%d\n",
			     driver_name, self->io.irq);
		return -EAGAIN;
	}
	/*
	 * Always allocate the DMA channel after the IRQ, and clean up on 
	 * failure.
	 */
	if (request_dma(self->io.dma, dev->name)) {
		IRDA_WARNING("%s, unable to allocate dma=%d\n",
			     driver_name, self->io.dma);
		free_irq(self->io.irq, dev);
		return -EAGAIN;
	}
	
	/* Save current bank */
	bank = inb(iobase+BSR);
	
	/* turn on interrupts */
	switch_bank(iobase, BANK0);
	outb(IER_LS_IE | IER_RXHDL_IE, iobase+IER);

	/* Restore bank register */
	outb(bank, iobase+BSR);

	/* Ready to play! */
	netif_start_queue(dev);
	
	/* Give self a hardware name */
	sprintf(hwname, "NSC-FIR @ 0x%03x", self->io.fir_base);

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

	return 0;
}

/*
 * Function nsc_ircc_net_close (dev)
 *
 *    Stop the device
 *
 */
static int nsc_ircc_net_close(struct net_device *dev)
{
	struct nsc_ircc_cb *self;
	int iobase;
	__u8 bank;

	IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
	
	IRDA_ASSERT(dev != NULL, return -1;);

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

	/* Stop device */
	netif_stop_queue(dev);
	
	/* Stop and remove instance of IrLAP */
	if (self->irlap)
		irlap_close(self->irlap);
	self->irlap = NULL;
	
	iobase = self->io.fir_base;

	disable_dma(self->io.dma);

	/* Save current bank */
	bank = inb(iobase+BSR);

	/* Disable interrupts */
	switch_bank(iobase, BANK0);
	outb(0, iobase+IER); 
       
	free_irq(self->io.irq, dev);
	free_dma(self->io.dma);

	/* Restore bank register */
	outb(bank, iobase+BSR);

	return 0;
}

/*
 * Function nsc_ircc_net_ioctl (dev, rq, cmd)
 *
 *    Process IOCTL commands for this device
 *
 */
static int nsc_ircc_net_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
	struct if_irda_req *irq = (struct if_irda_req *) rq;
	struct nsc_ircc_cb *self;
	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;
			break;
		}
		spin_lock_irqsave(&self->lock, flags);
		nsc_ircc_change_speed(self, irq->ifr_baudrate);
		spin_unlock_irqrestore(&self->lock, flags);
		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 */
		/* This is already protected */
		irq->ifr_receiving = nsc_ircc_is_receiving(self);
		break;
	default:
		ret = -EOPNOTSUPP;
	}
	return ret;
}

static struct net_device_stats *nsc_ircc_net_get_stats(struct net_device *dev)
{
	struct nsc_ircc_cb *self = (struct nsc_ircc_cb *) dev->priv;
	
	return &self->stats;
}

static int nsc_ircc_suspend(struct platform_device *dev, pm_message_t state)
{
     	struct nsc_ircc_cb *self = platform_get_drvdata(dev);
 	int bank;
	unsigned long flags;
 	int iobase = self->io.fir_base;

	if (self->io.suspended)
		return 0;

	IRDA_DEBUG(1, "%s, Suspending\n", driver_name);

	rtnl_lock();
	if (netif_running(self->netdev)) {
		netif_device_detach(self->netdev);
		spin_lock_irqsave(&self->lock, flags);
		/* Save current bank */
		bank = inb(iobase+BSR);

		/* Disable interrupts */
		switch_bank(iobase, BANK0);
		outb(0, iobase+IER);

		/* Restore bank register */
		outb(bank, iobase+BSR);

		spin_unlock_irqrestore(&self->lock, flags);
		free_irq(self->io.irq, self->netdev);
		disable_dma(self->io.dma);
	}
	self->io.suspended = 1;
	rtnl_unlock();

	return 0;
}

static int nsc_ircc_resume(struct platform_device *dev)
{
 	struct nsc_ircc_cb *self = platform_get_drvdata(dev);
 	unsigned long flags;

	if (!self->io.suspended)
		return 0;

	IRDA_DEBUG(1, "%s, Waking up\n", driver_name);

	rtnl_lock();
	nsc_ircc_setup(&self->io);
	nsc_ircc_init_dongle_interface(self->io.fir_base, self->io.dongle_id);

	if (netif_running(self->netdev)) {
		if (request_irq(self->io.irq, nsc_ircc_interrupt, 0,
				self->netdev->name, self->netdev)) {
 		    	IRDA_WARNING("%s, unable to allocate irq=%d\n",
				     driver_name, self->io.irq);

			/*
			 * Don't fail resume process, just kill this
			 * network interface
			 */
			unregister_netdevice(self->netdev);
		} else {
			spin_lock_irqsave(&self->lock, flags);
			nsc_ircc_change_speed(self, self->io.speed);
			spin_unlock_irqrestore(&self->lock, flags);
			netif_device_attach(self->netdev);
		}

	} else {
		spin_lock_irqsave(&self->lock, flags);
		nsc_ircc_change_speed(self, 9600);
		spin_unlock_irqrestore(&self->lock, flags);
	}
	self->io.suspended = 0;
	rtnl_unlock();

 	return 0;
}

MODULE_AUTHOR("Dag Brattli <[e-mail]>");
MODULE_DESCRIPTION("NSC IrDA Device Driver");
MODULE_LICENSE("GPL");


module_param(qos_mtt_bits, int, 0);
MODULE_PARM_DESC(qos_mtt_bits, "Minimum Turn Time");
module_param_array(io, int, NULL, 0);
MODULE_PARM_DESC(io, "Base I/O addresses");
module_param_array(irq, int, NULL, 0);
MODULE_PARM_DESC(irq, "IRQ lines");
module_param_array(dma, int, NULL, 0);
MODULE_PARM_DESC(dma, "DMA channels");
module_param(dongle_id, int, 0);
MODULE_PARM_DESC(dongle_id, "Type-id of used dongle");

module_init(nsc_ircc_init);
module_exit(nsc_ircc_cleanup);