pxaficp_ir.c

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	 * of this frame.
	 */
	if (speed != si->speed && speed != -1)
		si->newspeed = speed;

	/*
	 * If this is an empty frame, we can bypass a lot.
	 */
	if (skb->len == 0) {
		if (si->newspeed) {
			si->newspeed = 0;
			pxa_irda_set_speed(si, speed);
		}
		dev_kfree_skb(skb);
		return 0;
	}

	netif_stop_queue(dev);

	if (!IS_FIR(si)) {
		si->tx_buff.data = si->tx_buff.head;
		si->tx_buff.len  = async_wrap_skb(skb, si->tx_buff.data, si->tx_buff.truesize);

		/* Disable STUART interrupts and switch to transmit mode. */
		STIER = 0;
		STISR = IrSR_IR_TRANSMIT_ON | IrSR_XMODE_PULSE_1_6;

		/* enable STUART and transmit interrupts */
		STIER = IER_UUE | IER_TIE;
	} else {
		unsigned long mtt = irda_get_mtt(skb);

		si->dma_tx_buff_len = skb->len;
		memcpy(si->dma_tx_buff, skb->data, skb->len);

		if (mtt)
			while ((unsigned)(OSCR - si->last_oscr)/4 < mtt)
				cpu_relax();

		/* stop RX DMA,  disable FICP */
		DCSR(si->rxdma) &= ~DCSR_RUN;
		ICCR0 = 0;

		pxa_irda_fir_dma_tx_start(si);
		ICCR0 = ICCR0_ITR | ICCR0_TXE;
	}

	dev_kfree_skb(skb);
	dev->trans_start = jiffies;
	return 0;
}

static int pxa_irda_ioctl(struct net_device *dev, struct ifreq *ifreq, int cmd)
{
	struct if_irda_req *rq = (struct if_irda_req *)ifreq;
	struct pxa_irda *si = netdev_priv(dev);
	int ret;

	switch (cmd) {
	case SIOCSBANDWIDTH:
		ret = -EPERM;
		if (capable(CAP_NET_ADMIN)) {
			/*
			 * We are unable to set the speed if the
			 * device is not running.
			 */
			if (netif_running(dev)) {
				ret = pxa_irda_set_speed(si,
						rq->ifr_baudrate);
			} else {
				printk(KERN_INFO "pxa_ir: SIOCSBANDWIDTH: !netif_running\n");
				ret = 0;
			}
		}
		break;

	case SIOCSMEDIABUSY:
		ret = -EPERM;
		if (capable(CAP_NET_ADMIN)) {
			irda_device_set_media_busy(dev, TRUE);
			ret = 0;
		}
		break;

	case SIOCGRECEIVING:
		ret = 0;
		rq->ifr_receiving = IS_FIR(si) ? 0
					: si->rx_buff.state != OUTSIDE_FRAME;
		break;

	default:
		ret = -EOPNOTSUPP;
		break;
	}

	return ret;
}

static struct net_device_stats *pxa_irda_stats(struct net_device *dev)
{
	struct pxa_irda *si = netdev_priv(dev);
	return &si->stats;
}

static void pxa_irda_startup(struct pxa_irda *si)
{
	/* Disable STUART interrupts */
	STIER = 0;
	/* enable STUART interrupt to the processor */
	STMCR = MCR_OUT2;
	/* configure SIR frame format: StartBit - Data 7 ... Data 0 - Stop Bit */
	STLCR = LCR_WLS0 | LCR_WLS1;
	/* enable FIFO, we use FIFO to improve performance */
	STFCR = FCR_TRFIFOE | FCR_ITL_32;

	/* disable FICP */
	ICCR0 = 0;
	/* configure FICP ICCR2 */
	ICCR2 = ICCR2_TXP | ICCR2_TRIG_32;

	/* configure DMAC */
	DRCMR17 = si->rxdma | DRCMR_MAPVLD;
	DRCMR18 = si->txdma | DRCMR_MAPVLD;

	/* force SIR reinitialization */
	si->speed = 4000000;
	pxa_irda_set_speed(si, 9600);

	printk(KERN_DEBUG "pxa_ir: irda startup\n");
}

static void pxa_irda_shutdown(struct pxa_irda *si)
{
	unsigned long flags;

	local_irq_save(flags);

	/* disable STUART and interrupt */
	STIER = 0;
	/* disable STUART SIR mode */
	STISR = 0;
	/* disable the STUART clock */
	pxa_set_cken(CKEN5_STUART, 0);

	/* disable DMA */
	DCSR(si->txdma) &= ~DCSR_RUN;
	DCSR(si->rxdma) &= ~DCSR_RUN;
	/* disable FICP */
	ICCR0 = 0;
	/* disable the FICP clock */
	pxa_set_cken(CKEN13_FICP, 0);

	DRCMR17 = 0;
	DRCMR18 = 0;

	local_irq_restore(flags);

	/* power off board transceiver */
	si->pdata->transceiver_mode(si->dev, IR_OFF);

	printk(KERN_DEBUG "pxa_ir: irda shutdown\n");
}

static int pxa_irda_start(struct net_device *dev)
{
	struct pxa_irda *si = netdev_priv(dev);
	int err;

	si->speed = 9600;

	err = request_irq(IRQ_STUART, pxa_irda_sir_irq, 0, dev->name, dev);
	if (err)
		goto err_irq1;

	err = request_irq(IRQ_ICP, pxa_irda_fir_irq, 0, dev->name, dev);
	if (err)
		goto err_irq2;

	/*
	 * The interrupt must remain disabled for now.
	 */
	disable_irq(IRQ_STUART);
	disable_irq(IRQ_ICP);

	err = -EBUSY;
	si->rxdma = pxa_request_dma("FICP_RX",DMA_PRIO_LOW, pxa_irda_fir_dma_rx_irq, dev);
	if (si->rxdma < 0)
		goto err_rx_dma;

	si->txdma = pxa_request_dma("FICP_TX",DMA_PRIO_LOW, pxa_irda_fir_dma_tx_irq, dev);
	if (si->txdma < 0)
		goto err_tx_dma;

	err = -ENOMEM;
	si->dma_rx_buff = dma_alloc_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT,
					     &si->dma_rx_buff_phy, GFP_KERNEL );
	if (!si->dma_rx_buff)
		goto err_dma_rx_buff;

	si->dma_tx_buff = dma_alloc_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT,
					     &si->dma_tx_buff_phy, GFP_KERNEL );
	if (!si->dma_tx_buff)
		goto err_dma_tx_buff;

	/* Setup the serial port for the initial speed. */
	pxa_irda_startup(si);

	/*
	 * Open a new IrLAP layer instance.
	 */
	si->irlap = irlap_open(dev, &si->qos, "pxa");
	err = -ENOMEM;
	if (!si->irlap)
		goto err_irlap;

	/*
	 * Now enable the interrupt and start the queue
	 */
	enable_irq(IRQ_STUART);
	enable_irq(IRQ_ICP);
	netif_start_queue(dev);

	printk(KERN_DEBUG "pxa_ir: irda driver opened\n");

	return 0;

err_irlap:
	pxa_irda_shutdown(si);
	dma_free_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT, si->dma_tx_buff, si->dma_tx_buff_phy);
err_dma_tx_buff:
	dma_free_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT, si->dma_rx_buff, si->dma_rx_buff_phy);
err_dma_rx_buff:
	pxa_free_dma(si->txdma);
err_tx_dma:
	pxa_free_dma(si->rxdma);
err_rx_dma:
	free_irq(IRQ_ICP, dev);
err_irq2:
	free_irq(IRQ_STUART, dev);
err_irq1:

	return err;
}

static int pxa_irda_stop(struct net_device *dev)
{
	struct pxa_irda *si = netdev_priv(dev);

	netif_stop_queue(dev);

	pxa_irda_shutdown(si);

	/* Stop IrLAP */
	if (si->irlap) {
		irlap_close(si->irlap);
		si->irlap = NULL;
	}

	free_irq(IRQ_STUART, dev);
	free_irq(IRQ_ICP, dev);

	pxa_free_dma(si->rxdma);
	pxa_free_dma(si->txdma);

	if (si->dma_rx_buff)
		dma_free_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT, si->dma_tx_buff, si->dma_tx_buff_phy);
	if (si->dma_tx_buff)
		dma_free_coherent(si->dev, IRDA_FRAME_SIZE_LIMIT, si->dma_rx_buff, si->dma_rx_buff_phy);

	printk(KERN_DEBUG "pxa_ir: irda driver closed\n");
	return 0;
}

static int pxa_irda_suspend(struct platform_device *_dev, pm_message_t state)
{
	struct net_device *dev = platform_get_drvdata(_dev);
	struct pxa_irda *si;

	if (dev && netif_running(dev)) {
		si = netdev_priv(dev);
		netif_device_detach(dev);
		pxa_irda_shutdown(si);
	}

	return 0;
}

static int pxa_irda_resume(struct platform_device *_dev)
{
	struct net_device *dev = platform_get_drvdata(_dev);
	struct pxa_irda *si;

	if (dev && netif_running(dev)) {
		si = netdev_priv(dev);
		pxa_irda_startup(si);
		netif_device_attach(dev);
		netif_wake_queue(dev);
	}

	return 0;
}


static int pxa_irda_init_iobuf(iobuff_t *io, int size)
{
	io->head = kmalloc(size, GFP_KERNEL | GFP_DMA);
	if (io->head != NULL) {
		io->truesize = size;
		io->in_frame = FALSE;
		io->state    = OUTSIDE_FRAME;
		io->data     = io->head;
	}
	return io->head ? 0 : -ENOMEM;
}

static int pxa_irda_probe(struct platform_device *pdev)
{
	struct net_device *dev;
	struct pxa_irda *si;
	unsigned int baudrate_mask;
	int err;

	if (!pdev->dev.platform_data)
		return -ENODEV;

	err = request_mem_region(__PREG(STUART), 0x24, "IrDA") ? 0 : -EBUSY;
	if (err)
		goto err_mem_1;

	err = request_mem_region(__PREG(FICP), 0x1c, "IrDA") ? 0 : -EBUSY;
	if (err)
		goto err_mem_2;

	dev = alloc_irdadev(sizeof(struct pxa_irda));
	if (!dev)
		goto err_mem_3;

	si = netdev_priv(dev);
	si->dev = &pdev->dev;
	si->pdata = pdev->dev.platform_data;

	/*
	 * Initialise the SIR buffers
	 */
	err = pxa_irda_init_iobuf(&si->rx_buff, 14384);
	if (err)
		goto err_mem_4;
	err = pxa_irda_init_iobuf(&si->tx_buff, 4000);
	if (err)
		goto err_mem_5;

	dev->hard_start_xmit	= pxa_irda_hard_xmit;
	dev->open		= pxa_irda_start;
	dev->stop		= pxa_irda_stop;
	dev->do_ioctl		= pxa_irda_ioctl;
	dev->get_stats		= pxa_irda_stats;

	irda_init_max_qos_capabilies(&si->qos);

	baudrate_mask = 0;
	if (si->pdata->transceiver_cap & IR_SIRMODE)
		baudrate_mask |= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
	if (si->pdata->transceiver_cap & IR_FIRMODE)
		baudrate_mask |= IR_4000000 << 8;

	si->qos.baud_rate.bits &= baudrate_mask;
	si->qos.min_turn_time.bits = 7;  /* 1ms or more */

	irda_qos_bits_to_value(&si->qos);

	err = register_netdev(dev);

	if (err == 0)
		dev_set_drvdata(&pdev->dev, dev);

	if (err) {
		kfree(si->tx_buff.head);
err_mem_5:
		kfree(si->rx_buff.head);
err_mem_4:
		free_netdev(dev);
err_mem_3:
		release_mem_region(__PREG(FICP), 0x1c);
err_mem_2:
		release_mem_region(__PREG(STUART), 0x24);
	}
err_mem_1:
	return err;
}

static int pxa_irda_remove(struct platform_device *_dev)
{
	struct net_device *dev = platform_get_drvdata(_dev);

	if (dev) {
		struct pxa_irda *si = netdev_priv(dev);
		unregister_netdev(dev);
		kfree(si->tx_buff.head);
		kfree(si->rx_buff.head);
		free_netdev(dev);
	}

	release_mem_region(__PREG(STUART), 0x24);
	release_mem_region(__PREG(FICP), 0x1c);

	return 0;
}

static struct platform_driver pxa_ir_driver = {
	.driver         = {
		.name   = "pxa2xx-ir",
	},
	.probe		= pxa_irda_probe,
	.remove		= pxa_irda_remove,
	.suspend	= pxa_irda_suspend,
	.resume		= pxa_irda_resume,
};

static int __init pxa_irda_init(void)
{
	return platform_driver_register(&pxa_ir_driver);
}

static void __exit pxa_irda_exit(void)
{
	platform_driver_unregister(&pxa_ir_driver);
}

module_init(pxa_irda_init);
module_exit(pxa_irda_exit);

MODULE_LICENSE("GPL");