Commit 3afb6e9c authored by Russell King's avatar Russell King Committed by Russell King
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[ARM] dma: factor out code looking up the DMA channel 



This is a preparitory patch to allow us to easily change the way we
add and lookup DMA channel structures.

Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
parent 1df81302

arch/arm/kernel/dma.c

+24 −14
Original line number Diff line number Diff line
@@ -25,6 +25,16 @@ EXPORT_SYMBOL(dma_spin_lock); 


static dma_t dma_chan[MAX_DMA_CHANNELS];



static inline dma_t *dma_channel(unsigned int chan)

{

	dma_t *dma = dma_chan + chan;



	if (chan >= MAX_DMA_CHANNELS || !dma->d_ops)

		return NULL;



	return dma;

}



/*

 * Request DMA channel

 *
@@ -32,10 +42,10 @@ static dma_t dma_chan[MAX_DMA_CHANNELS]; 
 */

int request_dma(unsigned int chan, const char *device_id)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);

	int ret;



	if (chan >= MAX_DMA_CHANNELS || !dma->d_ops)

	if (!dma)

		goto bad_dma;



	if (xchg(&dma->lock, 1) != 0)
@@ -70,9 +80,9 @@ EXPORT_SYMBOL(request_dma); 
 */

void free_dma(unsigned int chan)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);



	if (chan >= MAX_DMA_CHANNELS || !dma->d_ops)

	if (!dma)

		goto bad_dma;



	if (dma->active) {
@@ -99,7 +109,7 @@ EXPORT_SYMBOL(free_dma); 
 */

void set_dma_sg (unsigned int chan, struct scatterlist *sg, int nr_sg)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);



	if (dma->active)

		printk(KERN_ERR "dma%d: altering DMA SG while "
@@ -117,7 +127,7 @@ EXPORT_SYMBOL(set_dma_sg); 
 */

void __set_dma_addr (unsigned int chan, void *addr)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);



	if (dma->active)

		printk(KERN_ERR "dma%d: altering DMA address while "
@@ -135,7 +145,7 @@ EXPORT_SYMBOL(__set_dma_addr); 
 */

void set_dma_count (unsigned int chan, unsigned long count)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);



	if (dma->active)

		printk(KERN_ERR "dma%d: altering DMA count while "
@@ -151,7 +161,7 @@ EXPORT_SYMBOL(set_dma_count); 
 */

void set_dma_mode (unsigned int chan, dmamode_t mode)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);



	if (dma->active)

		printk(KERN_ERR "dma%d: altering DMA mode while "
@@ -166,7 +176,7 @@ EXPORT_SYMBOL(set_dma_mode); 
 */

void enable_dma (unsigned int chan)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);



	if (!dma->lock)

		goto free_dma;
@@ -187,7 +197,7 @@ EXPORT_SYMBOL(enable_dma); 
 */

void disable_dma (unsigned int chan)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);



	if (!dma->lock)

		goto free_dma;
@@ -209,7 +219,8 @@ EXPORT_SYMBOL(disable_dma); 
 */

int dma_channel_active(unsigned int chan)

{

	return dma_chan[chan].active;

	dma_t *dma = dma_channel(chan);

	return dma->active;

}

EXPORT_SYMBOL(dma_channel_active);
@@ -221,7 +232,7 @@ EXPORT_SYMBOL(set_dma_page); 


void set_dma_speed(unsigned int chan, int cycle_ns)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);

	int ret = 0;



	if (dma->d_ops->setspeed)
@@ -232,7 +243,7 @@ EXPORT_SYMBOL(set_dma_speed); 


int get_dma_residue(unsigned int chan)

{

	dma_t *dma = dma_chan + chan;

	dma_t *dma = dma_channel(chan);

	int ret = 0;



	if (dma->d_ops->residue)
@@ -247,5 +258,4 @@ static int __init init_dma(void) 
	arch_dma_init(dma_chan);

	return 0;

}



core_initcall(init_dma);