[patch 005/198] arm: add comment about dma_supported()

[patch 005/198] arm: add comment about dma_supported()

[akpm]

From: Russell King <rmk+lkml@arm.linux.org.uk>

The ARM dma_supported() is rather basic, and I don't think it takes into
account everything that it should do (eg, whether the mask agrees with what
we'd return for GFP_DMA allocations).  Note this.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 25-akpm/include/asm-arm/dma-mapping.h |    3 +++
 1 files changed, 3 insertions(+)

diff -puN include/asm-arm/dma-mapping.h~arm-add-comment-about-dma_supported include/asm-arm/dma-mapping.h
--- 25/include/asm-arm/dma-mapping.h~arm-add-comment-about-dma_supported	2005-04-12 03:21:04.755413968 -0700
+++ 25-akpm/include/asm-arm/dma-mapping.h	2005-04-12 03:21:04.758413512 -0700
@@ -21,6 +21,9 @@ extern void consistent_sync(void *kaddr,
  * properly.  For example, if your device can only drive the low 24-bits
  * during bus mastering, then you would pass 0x00ffffff as the mask
  * to this function.
+ *
+ * FIXME: This should really be a platform specific issue - we should
+ * return false if GFP_DMA allocations may not satisfy the supplied 'mask'.
  */
 static inline int dma_supported(struct device *dev, u64 mask)
 {
_