Hi Jefrey, Thank you for the patch. On Thu, May 16, 2024 at 08:20:42PM +0800, Yunfei Dong wrote: > From: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx> > > Adds documentation for V4L2_MEMORY_FLAG_RESTRICTED. > > Signed-off-by: Jeffrey Kardatzke <jkardatzke@xxxxxxxxxx> > Signed-off-by: Yunfei Dong <yunfei.dong@xxxxxxxxxxxx> > --- > Documentation/userspace-api/media/v4l/buffer.rst | 10 +++++++++- > 1 file changed, 9 insertions(+), 1 deletion(-) > > diff --git a/Documentation/userspace-api/media/v4l/buffer.rst b/Documentation/userspace-api/media/v4l/buffer.rst > index 52bbee81c080..807e43bfed2b 100644 > --- a/Documentation/userspace-api/media/v4l/buffer.rst > +++ b/Documentation/userspace-api/media/v4l/buffer.rst > @@ -696,7 +696,7 @@ enum v4l2_memory > > .. _memory-flags: > > -Memory Consistency Flags > +Memory Flags > ------------------------ > > .. raw:: latex > @@ -728,6 +728,14 @@ Memory Consistency Flags > only if the buffer is used for :ref:`memory mapping <mmap>` I/O and the > queue reports the :ref:`V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS > <V4L2-BUF-CAP-SUPPORTS-MMAP-CACHE-HINTS>` capability. > + * .. _`V4L2-MEMORY-FLAG-RESTRICTED`: > + > + - ``V4L2_MEMORY_FLAG_RESTRICTED`` > + - 0x00000002 > + - The queued buffers are expected to be in restricted memory. If not, an > + error will be returned. This flag can only be used with ``V4L2_MEMORY_DMABUF``. > + Typically restricted buffers are allocated using a restricted dma-heap. This flag > + can only be specified if the ``V4L2_BUF_CAP_SUPPORTS_RESTRICTED_MEM`` is set. Why is this flag needed ? Given that the usage model requires the V4L2 device to be a dma buf importer, why would userspace set the V4L2_BUF_CAP_SUPPORTS_RESTRICTED_MEM flag and pass a non-restricted buffer to the device ? The V4L2_BUF_CAP_SUPPORTS_RESTRICTED_MEM flag also needs to be documented in the relevant section, I don't think that's done in this series. > > .. raw:: latex > -- Regards, Laurent Pinchart
