diff options
Diffstat (limited to 'arch/arm/mm/dma-mapping.c')
-rw-r--r-- | arch/arm/mm/dma-mapping.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 9f312248d5af..7bf3e6fdfb57 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c | |||
@@ -512,3 +512,95 @@ void dma_cache_maint(const void *start, size_t size, int direction) | |||
512 | } | 512 | } |
513 | } | 513 | } |
514 | EXPORT_SYMBOL(dma_cache_maint); | 514 | EXPORT_SYMBOL(dma_cache_maint); |
515 | |||
516 | #ifndef CONFIG_DMABOUNCE | ||
517 | /** | ||
518 | * dma_map_sg - map a set of SG buffers for streaming mode DMA | ||
519 | * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices | ||
520 | * @sg: list of buffers | ||
521 | * @nents: number of buffers to map | ||
522 | * @dir: DMA transfer direction | ||
523 | * | ||
524 | * Map a set of buffers described by scatterlist in streaming mode for DMA. | ||
525 | * This is the scatter-gather version of the dma_map_single interface. | ||
526 | * Here the scatter gather list elements are each tagged with the | ||
527 | * appropriate dma address and length. They are obtained via | ||
528 | * sg_dma_{address,length}. | ||
529 | * | ||
530 | * Device ownership issues as mentioned for dma_map_single are the same | ||
531 | * here. | ||
532 | */ | ||
533 | int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, | ||
534 | enum dma_data_direction dir) | ||
535 | { | ||
536 | struct scatterlist *s; | ||
537 | int i; | ||
538 | |||
539 | for_each_sg(sg, s, nents, i) { | ||
540 | s->dma_address = page_to_dma(dev, sg_page(s)) + s->offset; | ||
541 | |||
542 | if (!arch_is_coherent()) | ||
543 | dma_cache_maint(sg_virt(s), s->length, dir); | ||
544 | } | ||
545 | |||
546 | return nents; | ||
547 | } | ||
548 | EXPORT_SYMBOL(dma_map_sg); | ||
549 | |||
550 | /** | ||
551 | * dma_unmap_sg - unmap a set of SG buffers mapped by dma_map_sg | ||
552 | * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices | ||
553 | * @sg: list of buffers | ||
554 | * @nents: number of buffers to unmap (returned from dma_map_sg) | ||
555 | * @dir: DMA transfer direction (same as was passed to dma_map_sg) | ||
556 | * | ||
557 | * Unmap a set of streaming mode DMA translations. Again, CPU access | ||
558 | * rules concerning calls here are the same as for dma_unmap_single(). | ||
559 | */ | ||
560 | void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, | ||
561 | enum dma_data_direction dir) | ||
562 | { | ||
563 | /* nothing to do */ | ||
564 | } | ||
565 | EXPORT_SYMBOL(dma_unmap_sg); | ||
566 | |||
567 | /** | ||
568 | * dma_sync_sg_for_cpu | ||
569 | * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices | ||
570 | * @sg: list of buffers | ||
571 | * @nents: number of buffers to map (returned from dma_map_sg) | ||
572 | * @dir: DMA transfer direction (same as was passed to dma_map_sg) | ||
573 | */ | ||
574 | void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, | ||
575 | int nents, enum dma_data_direction dir) | ||
576 | { | ||
577 | struct scatterlist *s; | ||
578 | int i; | ||
579 | |||
580 | for_each_sg(sg, s, nents, i) { | ||
581 | if (!arch_is_coherent()) | ||
582 | dma_cache_maint(sg_virt(s), s->length, dir); | ||
583 | } | ||
584 | } | ||
585 | EXPORT_SYMBOL(dma_sync_sg_for_cpu); | ||
586 | |||
587 | /** | ||
588 | * dma_sync_sg_for_device | ||
589 | * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices | ||
590 | * @sg: list of buffers | ||
591 | * @nents: number of buffers to map (returned from dma_map_sg) | ||
592 | * @dir: DMA transfer direction (same as was passed to dma_map_sg) | ||
593 | */ | ||
594 | void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, | ||
595 | int nents, enum dma_data_direction dir) | ||
596 | { | ||
597 | struct scatterlist *s; | ||
598 | int i; | ||
599 | |||
600 | for_each_sg(sg, s, nents, i) { | ||
601 | if (!arch_is_coherent()) | ||
602 | dma_cache_maint(sg_virt(s), s->length, dir); | ||
603 | } | ||
604 | } | ||
605 | EXPORT_SYMBOL(dma_sync_sg_for_device); | ||
606 | #endif | ||