Commit 885767ca authored by Russell King's avatar Russell King
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NET: sa11x0-ir: containerize DMA data 



Both the transmit and receive DMA store identical data: the skb, dma
address, and the dma registers.  Move this data into its own data
structure.  The following replacements were used:

	rxskb -> dma_rx.skb
	rxbuf_dma -> dma_rx.dma
	rxdma -> dma_rx.regs

	txskb -> dma_tx.skb
	txbuf_dma -> dma_tx.dma
	txdma -> dma_tx.regs

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent e556fdbd

drivers/net/irda/sa1100_ir.c

+48 −46
Original line number Diff line number Diff line
@@ -43,6 +43,12 @@ static int power_level = 3; 
static int tx_lpm;

static int max_rate = 4000000;



struct sa1100_buf {

	struct sk_buff		*skb;

	dma_addr_t		dma;

	dma_regs_t		*regs;

};



struct sa1100_irda {

	unsigned char		hscr0;

	unsigned char		utcr4;
@@ -52,12 +58,8 @@ struct sa1100_irda { 
	int			speed;

	int			newspeed;



	struct sk_buff		*txskb;

	struct sk_buff		*rxskb;

	dma_addr_t		txbuf_dma;

	dma_addr_t		rxbuf_dma;

	dma_regs_t		*txdma;

	dma_regs_t		*rxdma;

	struct sa1100_buf	dma_rx;

	struct sa1100_buf	dma_tx;



	struct device		*dev;

	struct irda_platform_data *pdata;
@@ -77,11 +79,11 @@ struct sa1100_irda { 
 */

static int sa1100_irda_rx_alloc(struct sa1100_irda *si)

{

	if (si->rxskb)

	if (si->dma_rx.skb)

		return 0;



	si->rxskb = alloc_skb(HPSIR_MAX_RXLEN + 1, GFP_ATOMIC);

	if (!si->rxskb) {

	si->dma_rx.skb = alloc_skb(HPSIR_MAX_RXLEN + 1, GFP_ATOMIC);

	if (!si->dma_rx.skb) {

		printk(KERN_ERR "sa1100_ir: out of memory for RX SKB\n");

		return -ENOMEM;

	}
@@ -90,13 +92,13 @@ static int sa1100_irda_rx_alloc(struct sa1100_irda *si) 
	 * Align any IP headers that may be contained

	 * within the frame.

	 */

	skb_reserve(si->rxskb, 1);

	skb_reserve(si->dma_rx.skb, 1);



	si->rxbuf_dma = dma_map_single(si->dev, si->rxskb->data,

	si->dma_rx.dma = dma_map_single(si->dev, si->dma_rx.skb->data,

					HPSIR_MAX_RXLEN,

					DMA_FROM_DEVICE);

	if (dma_mapping_error(si->dev, si->rxbuf_dma)) {

		dev_kfree_skb_any(si->rxskb);

	if (dma_mapping_error(si->dev, si->dma_rx.dma)) {

		dev_kfree_skb_any(si->dma_rx.skb);

		return -ENOMEM;

	}
@@ -109,7 +111,7 @@ static int sa1100_irda_rx_alloc(struct sa1100_irda *si) 
 */

static void sa1100_irda_rx_dma_start(struct sa1100_irda *si)

{

	if (!si->rxskb) {

	if (!si->dma_rx.skb) {

		printk(KERN_ERR "sa1100_ir: rx buffer went missing\n");

		return;

	}
@@ -122,8 +124,8 @@ static void sa1100_irda_rx_dma_start(struct sa1100_irda *si) 
	/*

	 * Enable the DMA, receiver and receive interrupt.

	 */

	sa1100_clear_dma(si->rxdma);

	sa1100_start_dma(si->rxdma, si->rxbuf_dma, HPSIR_MAX_RXLEN);

	sa1100_clear_dma(si->dma_rx.regs);

	sa1100_start_dma(si->dma_rx.regs, si->dma_rx.dma, HPSIR_MAX_RXLEN);

	Ser2HSCR0 = si->hscr0 | HSCR0_HSSP | HSCR0_RXE;

}
@@ -144,7 +146,7 @@ static int sa1100_irda_set_speed(struct sa1100_irda *si, int speed) 
		 * Stop the receive DMA.

		 */

		if (IS_FIR(si))

			sa1100_stop_dma(si->rxdma);

			sa1100_stop_dma(si->dma_rx.regs);



		local_irq_save(flags);
@@ -280,8 +282,8 @@ static void sa1100_irda_shutdown(struct sa1100_irda *si) 
	/*

	 * Stop all DMA activity.

	 */

	sa1100_stop_dma(si->rxdma);

	sa1100_stop_dma(si->txdma);

	sa1100_stop_dma(si->dma_rx.regs);

	sa1100_stop_dma(si->dma_tx.regs);



	/* Disable the port. */

	Ser2UTCR3 = 0;
@@ -460,7 +462,7 @@ static void sa1100_irda_hpsir_irq(struct net_device *dev) 


static void sa1100_irda_fir_error(struct sa1100_irda *si, struct net_device *dev)

{

	struct sk_buff *skb = si->rxskb;

	struct sk_buff *skb = si->dma_rx.skb;

	dma_addr_t dma_addr;

	unsigned int len, stat, data;
@@ -472,11 +474,11 @@ static void sa1100_irda_fir_error(struct sa1100_irda *si, struct net_device *dev 
	/*

	 * Get the current data position.

	 */

	dma_addr = sa1100_get_dma_pos(si->rxdma);

	len = dma_addr - si->rxbuf_dma;

	dma_addr = sa1100_get_dma_pos(si->dma_rx.regs);

	len = dma_addr - si->dma_rx.dma;

	if (len > HPSIR_MAX_RXLEN)

		len = HPSIR_MAX_RXLEN;

	dma_unmap_single(si->dev, si->rxbuf_dma, len, DMA_FROM_DEVICE);

	dma_unmap_single(si->dev, si->dma_rx.dma, len, DMA_FROM_DEVICE);



	do {

		/*
@@ -504,7 +506,7 @@ static void sa1100_irda_fir_error(struct sa1100_irda *si, struct net_device *dev 
	} while (Ser2HSSR0 & HSSR0_EIF);



	if (stat & HSSR1_EOF) {

		si->rxskb = NULL;

		si->dma_rx.skb = NULL;



		skb_put(skb, len);

		skb->dev = dev;
@@ -524,7 +526,7 @@ static void sa1100_irda_fir_error(struct sa1100_irda *si, struct net_device *dev 
		 * Remap the buffer - it was previously mapped, and we

		 * hope that this succeeds.

		 */

		si->rxbuf_dma = dma_map_single(si->dev, si->rxskb->data,

		si->dma_rx.dma = dma_map_single(si->dev, si->dma_rx.skb->data,

						HPSIR_MAX_RXLEN,

						DMA_FROM_DEVICE);

	}
@@ -543,7 +545,7 @@ static void sa1100_irda_fir_irq(struct net_device *dev) 
	/*

	 * Stop RX DMA

	 */

	sa1100_stop_dma(si->rxdma);

	sa1100_stop_dma(si->dma_rx.regs);



	/*

	 * Framing error - we throw away the packet completely.
@@ -600,9 +602,9 @@ static void sa1100_irda_txdma_irq(void *id) 
{

	struct net_device *dev = id;

	struct sa1100_irda *si = netdev_priv(dev);

	struct sk_buff *skb = si->txskb;

	struct sk_buff *skb = si->dma_tx.skb;



	si->txskb = NULL;

	si->dma_tx.skb = NULL;



	/*

	 * Wait for the transmission to complete.  Unfortunately,
@@ -620,7 +622,7 @@ static void sa1100_irda_txdma_irq(void *id) 


	/*

	 * Do we need to change speed?  Note that we're lazy

	 * here - we don't free the old rxskb.  We don't need

	 * here - we don't free the old dma_rx.skb.  We don't need

	 * to allocate a buffer either.

	 */

	if (si->newspeed) {
@@ -638,7 +640,7 @@ static void sa1100_irda_txdma_irq(void *id) 
	 * Account and free the packet.

	 */

	if (skb) {

		dma_unmap_single(si->dev, si->txbuf_dma, skb->len, DMA_TO_DEVICE);

		dma_unmap_single(si->dev, si->dma_tx.dma, skb->len, DMA_TO_DEVICE);

		dev->stats.tx_packets ++;

		dev->stats.tx_bytes += skb->len;

		dev_kfree_skb_irq(skb);
@@ -698,22 +700,22 @@ static int sa1100_irda_hard_xmit(struct sk_buff *skb, struct net_device *dev) 
		/*

		 * We must not be transmitting...

		 */

		BUG_ON(si->txskb);

		BUG_ON(si->dma_tx.skb);



		netif_stop_queue(dev);



		si->txskb = skb;

		si->txbuf_dma = dma_map_single(si->dev, skb->data,

		si->dma_tx.skb = skb;

		si->dma_tx.dma = dma_map_single(si->dev, skb->data,

					 skb->len, DMA_TO_DEVICE);

		if (dma_mapping_error(si->dev, si->txbuf_dma)) {

			si->txskb = NULL;

		if (dma_mapping_error(si->dev, si->dma_tx.dma)) {

			si->dma_tx.skb = NULL;

			netif_wake_queue(dev);

			dev->stats.tx_dropped++;

			dev_kfree_skb(skb);

			return NETDEV_TX_OK;

		}



		sa1100_start_dma(si->txdma, si->txbuf_dma, skb->len);

		sa1100_start_dma(si->dma_tx.regs, si->dma_tx.dma, skb->len);



		/*

		 * If we have a mean turn-around time, impose the specified
@@ -785,12 +787,12 @@ static int sa1100_irda_start(struct net_device *dev) 
		goto err_irq;



	err = sa1100_request_dma(DMA_Ser2HSSPRd, "IrDA receive",

				 NULL, NULL, &si->rxdma);

				 NULL, NULL, &si->dma_rx.regs);

	if (err)

		goto err_rx_dma;



	err = sa1100_request_dma(DMA_Ser2HSSPWr, "IrDA transmit",

				 sa1100_irda_txdma_irq, dev, &si->txdma);

				 sa1100_irda_txdma_irq, dev, &si->dma_tx.regs);

	if (err)

		goto err_tx_dma;
@@ -827,9 +829,9 @@ err_irlap: 
	si->open = 0;

	sa1100_irda_shutdown(si);

err_startup:

	sa1100_free_dma(si->txdma);

	sa1100_free_dma(si->dma_tx.regs);

err_tx_dma:

	sa1100_free_dma(si->rxdma);

	sa1100_free_dma(si->dma_rx.regs);

err_rx_dma:

	free_irq(dev->irq, dev);

err_irq:
@@ -847,11 +849,11 @@ static int sa1100_irda_stop(struct net_device *dev) 
	 * If we have been doing DMA receive, make sure we

	 * tidy that up cleanly.

	 */

	if (si->rxskb) {

		dma_unmap_single(si->dev, si->rxbuf_dma, HPSIR_MAX_RXLEN,

	if (si->dma_rx.skb) {

		dma_unmap_single(si->dev, si->dma_rx.dma, HPSIR_MAX_RXLEN,

				 DMA_FROM_DEVICE);

		dev_kfree_skb(si->rxskb);

		si->rxskb = NULL;

		dev_kfree_skb(si->dma_rx.skb);

		si->dma_rx.skb = NULL;

	}



	/* Stop IrLAP */
@@ -866,8 +868,8 @@ static int sa1100_irda_stop(struct net_device *dev) 
	/*

	 * Free resources

	 */

	sa1100_free_dma(si->txdma);

	sa1100_free_dma(si->rxdma);

	sa1100_free_dma(si->dma_tx.regs);

	sa1100_free_dma(si->dma_rx.regs);

	free_irq(dev->irq, dev);



	sa1100_set_power(si, 0);

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