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authorMauro Carvalho Chehab <mchehab+huawei@kernel.org>2020-03-03 16:50:33 +0100
committerVinod Koul <vkoul@kernel.org>2020-03-06 19:06:32 +0530
commitcf7da891b624983ffadd6b97ef63a0def3e985ad (patch)
treec667b01264322f578f2bf07bd7a1d8acb082ffb6 /Documentation/driver-api
parent25962e1a7f1d522f1b57ead2f266fab570042a70 (diff)
downloadlinux-cf7da891b624983ffadd6b97ef63a0def3e985ad.tar.bz2
docs: dmaengine: provider.rst: get rid of some warnings
Get rid of those warnings by adding extra blank lines: Documentation/driver-api/dmaengine/provider.rst:270: WARNING: Unexpected indentation. Documentation/driver-api/dmaengine/provider.rst:273: WARNING: Block quote ends without a blank line; unexpected unindent. Documentation/driver-api/dmaengine/provider.rst:288: WARNING: Unexpected indentation. Documentation/driver-api/dmaengine/provider.rst:290: WARNING: Block quote ends without a blank line; unexpected unindent. While here, use parenthesis after get_metadata_ptr/set_metadata_len, as, if some day someone adds a kerneldoc markup for those, it should automatically generate a cross-reference to them. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Link: https://lore.kernel.org/r/62cf2a87b379a92c9c0e5a40c2ae8a138b01fe0a.1583250595.git.mchehab+huawei@kernel.org Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'Documentation/driver-api')
-rw-r--r--Documentation/driver-api/dmaengine/provider.rst12
1 files changed, 10 insertions, 2 deletions
diff --git a/Documentation/driver-api/dmaengine/provider.rst b/Documentation/driver-api/dmaengine/provider.rst
index 790a15089f1f..56e5833e8a07 100644
--- a/Documentation/driver-api/dmaengine/provider.rst
+++ b/Documentation/driver-api/dmaengine/provider.rst
@@ -266,11 +266,15 @@ to use.
attached (via the dmaengine_desc_attach_metadata() helper to the descriptor.
From the DMA driver the following is expected for this mode:
+
- DMA_MEM_TO_DEV / DEV_MEM_TO_MEM
+
The data from the provided metadata buffer should be prepared for the DMA
controller to be sent alongside of the payload data. Either by copying to a
hardware descriptor, or highly coupled packet.
+
- DMA_DEV_TO_MEM
+
On transfer completion the DMA driver must copy the metadata to the client
provided metadata buffer before notifying the client about the completion.
After the transfer completion, DMA drivers must not touch the metadata
@@ -284,10 +288,14 @@ to use.
and dmaengine_desc_set_metadata_len() is provided as helper functions.
From the DMA driver the following is expected for this mode:
- - get_metadata_ptr
+
+ - get_metadata_ptr()
+
Should return a pointer for the metadata buffer, the maximum size of the
metadata buffer and the currently used / valid (if any) bytes in the buffer.
- - set_metadata_len
+
+ - set_metadata_len()
+
It is called by the clients after it have placed the metadata to the buffer
to let the DMA driver know the number of valid bytes provided.