From bcdb9040df9e1e2a16252791c43f9c40c2927dd3 Mon Sep 17 00:00:00 2001 From: Javier Martinez Canillas Date: Tue, 31 May 2016 13:56:08 -0300 Subject: [media] DocBook: mention the memory type to be set for all streaming I/O The DMA buffer importing streaming I/O section mentions the memory type value that has to be set when calling the VIDIOC_REQBUFS ioctl but this isn't mentioned in neither the Memory Mapping nor User Pointer sections. A user can know the values by looking at the examples but it's better to explicitly mention in the documentation, and also makes all sections about streaming I/O methods more consistent. Signed-off-by: Javier Martinez Canillas Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/DocBook/media/v4l/io.xml | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'Documentation/DocBook/media') diff --git a/Documentation/DocBook/media/v4l/io.xml b/Documentation/DocBook/media/v4l/io.xml index e09025d..21a3dde 100644 --- a/Documentation/DocBook/media/v4l/io.xml +++ b/Documentation/DocBook/media/v4l/io.xml @@ -88,7 +88,7 @@ function. capabilities field of &v4l2-capability; returned by the &VIDIOC-QUERYCAP; ioctl is set. There are two streaming methods, to determine if the memory mapping flavor is -supported applications must call the &VIDIOC-REQBUFS; ioctl. +supported applications must call the &VIDIOC-REQBUFS; ioctl with the memory type set to V4L2_MEMORY_MMAP. Streaming is an I/O method where only pointers to buffers are exchanged between application and driver, the data itself is not @@ -369,7 +369,7 @@ rest should be evident. capabilities field of &v4l2-capability; returned by the &VIDIOC-QUERYCAP; ioctl is set. If the particular user pointer method (not only memory mapping) is supported must be -determined by calling the &VIDIOC-REQBUFS; ioctl. +determined by calling the &VIDIOC-REQBUFS; ioctl with the memory type set to V4L2_MEMORY_USERPTR. This I/O method combines advantages of the read/write and memory mapping methods. Buffers (planes) are allocated by the application -- cgit v1.1