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[ARM] Update dma_map_sg()/dma_unmap_sg() API

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Update the ARM DMA scatter gather APIs for the scatterlist changes.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King
2008-09-25 16:30:57 +01:00
committed by Russell King
parent 0ddbccd118
commit afd1a321c4
3 changed files with 115 additions and 125 deletions
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92
arch/arm/mm/dma-mapping.c
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@@ -512,3 +512,95 @@ void dma_cache_maint(const void *start, size_t size, int direction)
}
}
EXPORT_SYMBOL(dma_cache_maint);
#ifndef CONFIG_DMABOUNCE
/**
* dma_map_sg - map a set of SG buffers for streaming mode DMA
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @sg: list of buffers
* @nents: number of buffers to map
* @dir: DMA transfer direction
*
* Map a set of buffers described by scatterlist in streaming mode for DMA.
* This is the scatter-gather version of the dma_map_single interface.
* Here the scatter gather list elements are each tagged with the
* appropriate dma address and length. They are obtained via
* sg_dma_{address,length}.
*
* Device ownership issues as mentioned for dma_map_single are the same
* here.
*/
int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir)
{
struct scatterlist *s;
int i;
for_each_sg(sg, s, nents, i) {
s->dma_address = page_to_dma(dev, sg_page(s)) + s->offset;
if (!arch_is_coherent())
dma_cache_maint(sg_virt(s), s->length, dir);
}
return nents;
}
EXPORT_SYMBOL(dma_map_sg);
/**
* dma_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @sg: list of buffers
* @nents: number of buffers to unmap (returned from dma_map_sg)
* @dir: DMA transfer direction (same as was passed to dma_map_sg)
*
* Unmap a set of streaming mode DMA translations. Again, CPU access
* rules concerning calls here are the same as for dma_unmap_single().
*/
void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction dir)
{
/* nothing to do */
}
EXPORT_SYMBOL(dma_unmap_sg);
/**
* dma_sync_sg_for_cpu
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @sg: list of buffers
* @nents: number of buffers to map (returned from dma_map_sg)
* @dir: DMA transfer direction (same as was passed to dma_map_sg)
*/
void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir)
{
struct scatterlist *s;
int i;
for_each_sg(sg, s, nents, i) {
if (!arch_is_coherent())
dma_cache_maint(sg_virt(s), s->length, dir);
}
}
EXPORT_SYMBOL(dma_sync_sg_for_cpu);
/**
* dma_sync_sg_for_device
* @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
* @sg: list of buffers
* @nents: number of buffers to map (returned from dma_map_sg)
* @dir: DMA transfer direction (same as was passed to dma_map_sg)
*/
void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
int nents, enum dma_data_direction dir)
{
struct scatterlist *s;
int i;
for_each_sg(sg, s, nents, i) {
if (!arch_is_coherent())
dma_cache_maint(sg_virt(s), s->length, dir);
}
}
EXPORT_SYMBOL(dma_sync_sg_for_device);
#endif