On 2/28/20 2:38 AM, Sergey Senozhatsky wrote: > On (20/02/27 13:36), Hans Verkuil wrote: >>> diff --git a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst >>> index bd08e4f77ae4..6a8a4d5de2f1 100644 >>> --- a/Documentation/media/uapi/v4l/vidioc-create-bufs.rst >>> +++ b/Documentation/media/uapi/v4l/vidioc-create-bufs.rst >>> @@ -121,7 +121,13 @@ than the number requested. >>> other changes, then set ``count`` to 0, ``memory`` to >>> ``V4L2_MEMORY_MMAP`` and ``format.type`` to the buffer type. >>> * - __u32 >>> - - ``reserved``\ [7] >>> + - ``flags`` >>> + - Specifies additional buffer management attributes. >>> + See :ref:`memory-flags`. Old drivers and applications must set it to >>> + zero. >> >> Drop the last sentence, it's not relevant. > > OK. > >>> + >>> + * - __u32 >>> + - ``reserved``\ [6] >>> - A place holder for future extensions. Drivers and applications >>> must set the array to zero. >> >> Old drivers and applications still think reserved is [7] and will zero this. > > OK. > > Hmm... If those apps use hard-coded size then we might have a problem. > If they use sizeof(reserved) then everything is OK. Shall we also have > a union here? No, apps will use sizeof(reserved). Regards, Hans > >>> diff --git a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst >>> index 917df6fb6486..e52cc4401fba 100644 >>> --- a/Documentation/media/uapi/v4l/vidioc-reqbufs.rst >>> +++ b/Documentation/media/uapi/v4l/vidioc-reqbufs.rst >>> @@ -112,10 +112,19 @@ aborting or finishing any DMA in progress, an implicit >>> ``V4L2_MEMORY_MMAP`` and ``type`` set to the buffer type. This will >>> free any previously allocated buffers, so this is typically something >>> that will be done at the start of the application. >>> - * - __u32 >>> + * - union >>> + - (anonymous) >> >> Anonymous unions are formatted a bit differently (I made a very recent patch >> that unified the union formatting in the v4l docs). See e.g. >> Documentation/media/uapi/v4l/vidioc-g-ext-ctrls.rst. > > OK, will take a look. > > -ss >
