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Documentation: DMA API: Be more explicit that nents is always the same

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The nents argument to the DMA API functions operating on scatterlists is
always the same. The documentation used different argument names and the
matter was not mentioned in Documentation/DMA-API-HOWTO.txt at all. Fix
these.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This commit is contained in:
Sakari Ailus
2015-09-23 14:41:09 +03:00
committed by Jonathan Corbet
parent c604503192
commit 7bc590b2fc
2 changed files with 8 additions and 3 deletions
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5
Documentation/DMA-API-HOWTO.txt
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@@ -681,6 +681,11 @@ or:
as appropriate.
PLEASE NOTE: The 'nents' argument to dma_sync_sg_for_cpu() and
dma_sync_sg_for_device() must be the same passed to
dma_map_sg(). It is _NOT_ the count returned by
dma_map_sg().
After the last DMA transfer call one of the DMA unmap routines
dma_unmap_{single,sg}(). If you don't touch the data from the first
dma_map_*() call till dma_unmap_*(), then you don't have to call the