pci_dma_sync_single was obsoleted long ago.
All the comments are generic, not architecture specific, simply describes
some of the DMA-API (and frv has the same comments in three files).
Documentation/DMA-API.txt have more detailed descriptions.
This removes the above obsolete and unnecessary DMA API comments. Let's
describe the DMA API in only Documentation/DMA-API.txt.
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: David Howells <dhowells@redhat.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
#include <asm/scatterlist.h>
#include <asm/io.h>
+/*
+ * See Documentation/DMA-API.txt for the description of how the
+ * following DMA API should work.
+ */
+
#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
void *dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp);
void dma_free_coherent(struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle);
-/*
- * Map a single buffer of the indicated size for DMA in streaming mode.
- * The 32-bit bus address to use is returned.
- *
- * Once the device is given the dma address, the device owns this memory
- * until either pci_unmap_single or pci_dma_sync_single is performed.
- */
extern dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction direction);
-/*
- * Unmap a single streaming mode DMA translation. The dma_addr and size
- * must match what was provided for in a previous pci_map_single call. All
- * other usages are undefined.
- *
- * After this call, reads by the cpu to the buffer are guarenteed to see
- * whatever the device wrote there.
- */
static inline
void dma_unmap_single(struct device *dev, dma_addr_t dma_addr, size_t size,
enum dma_data_direction direction)
BUG_ON(direction == DMA_NONE);
}
-/*
- * Map a set of buffers described by scatterlist in streaming
- * mode for DMA. This is the scather-gather version of the
- * above pci_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}(SG).
- *
- * NOTE: An implementation may be able to use a smaller number of
- * DMA address/length pairs than there are SG table elements.
- * (for example via virtual mapping capabilities)
- * The routine returns the number of addr/length pairs actually
- * used, at most nents.
- *
- * Device ownership issues as mentioned above for pci_map_single are
- * the same here.
- */
extern int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction direction);
-/*
- * Unmap a set of streaming mode DMA translations.
- * Again, cpu read rules concerning calls here are the same as for
- * pci_unmap_single() above.
- */
static inline
void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nhwentries,
enum dma_data_direction direction)
EXPORT_SYMBOL(dma_free_coherent);
-/*
- * Map a single buffer of the indicated size for DMA in streaming mode.
- * The 32-bit bus address to use is returned.
- *
- * Once the device is given the dma address, the device owns this memory
- * until either dma_unmap_single or pci_dma_sync_single is performed.
- */
dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction direction)
{
EXPORT_SYMBOL(dma_map_single);
-/*
- * Map a set of buffers described by scatterlist in streaming
- * mode for DMA. This is the scather-gather version of the
- * above 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}(SG).
- *
- * NOTE: An implementation may be able to use a smaller number of
- * DMA address/length pairs than there are SG table elements.
- * (for example via virtual mapping capabilities)
- * The routine returns the number of addr/length pairs actually
- * used, at most nents.
- *
- * Device ownership issues as mentioned above for dma_map_single are
- * the same here.
- */
int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction direction)
{
EXPORT_SYMBOL(dma_map_sg);
-/*
- * Map a single page of the indicated size for DMA in streaming mode.
- * The 32-bit bus address to use is returned.
- *
- * Device ownership issues as mentioned above for dma_map_single are
- * the same here.
- */
dma_addr_t dma_map_page(struct device *dev, struct page *page, unsigned long offset,
size_t size, enum dma_data_direction direction)
{
EXPORT_SYMBOL(dma_free_coherent);
-/*
- * Map a single buffer of the indicated size for DMA in streaming mode.
- * The 32-bit bus address to use is returned.
- *
- * Once the device is given the dma address, the device owns this memory
- * until either pci_unmap_single or pci_dma_sync_single is performed.
- */
dma_addr_t dma_map_single(struct device *dev, void *ptr, size_t size,
enum dma_data_direction direction)
{
EXPORT_SYMBOL(dma_map_single);
-/*
- * Map a set of buffers described by scatterlist in streaming
- * mode for DMA. This is the scather-gather version of the
- * above 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}(SG).
- *
- * NOTE: An implementation may be able to use a smaller number of
- * DMA address/length pairs than there are SG table elements.
- * (for example via virtual mapping capabilities)
- * The routine returns the number of addr/length pairs actually
- * used, at most nents.
- *
- * Device ownership issues as mentioned above for dma_map_single are
- * the same here.
- */
int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
enum dma_data_direction direction)
{
EXPORT_SYMBOL(dma_map_sg);
-/*
- * Map a single page of the indicated size for DMA in streaming mode.
- * The 32-bit bus address to use is returned.
- *
- * Device ownership issues as mentioned above for dma_map_single are
- * the same here.
- */
dma_addr_t dma_map_page(struct device *dev, struct page *page, unsigned long offset,
size_t size, enum dma_data_direction direction)
{