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Date: Wed, 22 May 2024 14:24:26 +0200
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From: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Subject: Re: [PATCH v6,04/24] v4l: add documentation for restricted memory
 flag
To: Yunfei Dong <yunfei.dong@mediatek.com>,
 Jeffrey Kardatzke <jkardatzke@google.com>,
 =?UTF-8?Q?N=C3=ADcolas_F_=2E_R_=2E_A_=2E_Prado?= <nfraprado@collabora.com>,
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Cc: Chen-Yu Tsai <wenst@chromium.org>, Yong Wu <yong.wu@mediatek.com>,
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References: <20240516122102.16379-1-yunfei.dong@mediatek.com>
 <20240516122102.16379-5-yunfei.dong@mediatek.com>
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Hi Yunfei & Jeffrey,

W dniu 16.05.2024 o 14:20, Yunfei Dong pisze:
> From: Jeffrey Kardatzke <jkardatzke@google.com>
> 
> Adds documentation for V4L2_MEMORY_FLAG_RESTRICTED.
> 

Why not in the patch where the flag is actually being added?
 From that commit until this commit it would be undocumented.

While at it...

> Signed-off-by: Jeffrey Kardatzke <jkardatzke@google.com>
> Signed-off-by: Yunfei Dong <yunfei.dong@mediatek.com>
> ---
>   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.

is V4L2_BUF_CAP_SUPPORTS_RESTRICTED_MEM documented? Can it be referenced here
in a way similar to how V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS is?

Regards,

Andrzej

>   
>   .. raw:: latex
>