RE: [PATCH] media: uapi: v4l: Change V4L2_TYPE_IS_CAPTURE condition

[Nas Chung <nas.chung@chipsnmedia.com>]

Hi, Michael.

Thank you for the feedback.

>-----Original Message-----
>From: Michael Tretter <m.tretter@pengutronix.de>
>Sent: Wednesday, May 22, 2024 4:55 PM
>To: Nas Chung <nas.chung@chipsnmedia.com>
>Cc: mchehab@kernel.org; linux-media@vger.kernel.org; linux-
>kernel@vger.kernel.org; Sebastian Fricke <sebastian.fricke@collabora.com>
>Subject: Re: [PATCH] media: uapi: v4l: Change V4L2_TYPE_IS_CAPTURE
>condition
>
>On Fri, 17 May 2024 18:49:40 +0900, Nas Chung wrote:
>> We expect V4L2_TYPE_IS_CAPTURE() macro allow only CAPTURE type.
>> But, Inverting OUTPUT type can allow undefined v4l2_buf_type.
>> Check CAPTURE type directly instead of inverting OUTPUT type.
>>
>> Signed-off-by: Nas Chung <nas.chung@chipsnmedia.com>
>> ---
>>  include/uapi/linux/videodev2.h | 8 +++++++-
>>  1 file changed, 7 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/uapi/linux/videodev2.h
>b/include/uapi/linux/videodev2.h
>> index fe6b67e83751..32b10e2b7695 100644
>> --- a/include/uapi/linux/videodev2.h
>> +++ b/include/uapi/linux/videodev2.h
>> @@ -171,7 +171,13 @@ enum v4l2_buf_type {
>>  	 || (type) == V4L2_BUF_TYPE_SDR_OUTPUT			\
>>  	 || (type) == V4L2_BUF_TYPE_META_OUTPUT)
>>
>> -#define V4L2_TYPE_IS_CAPTURE(type) (!V4L2_TYPE_IS_OUTPUT(type))
>> +#define V4L2_TYPE_IS_CAPTURE(type)				\
>> +	((type) == V4L2_BUF_TYPE_VIDEO_CAPTURE			\
>> +	 || (type) == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE	\
>> +	 || (type) == V4L2_BUF_TYPE_VBI_CAPTURE			\
>> +	 || (type) == V4L2_BUF_TYPE_SLICED_VBI_CAPTURE		\
>> +	 || (type) == V4L2_BUF_TYPE_SDR_CAPTURE			\
>> +	 || (type) == V4L2_BUF_TYPE_META_CAPTURE)
>
>Maybe adding a V4L2_TYPE_IS_VALID(type) macro would be helpful to define
>TYPE_IS_CAPTURE as all valid types that are not OUTPUT:
>
>	#define V4L2_TYPE_IS_VALID(type) \
>		((type) >= V4L2_BUF_TYPE_VIDEO_CAPTURE \
>		&& (type) <= V4L2_BUF_TYPE_META_OUTPUT)
>
>	#define V4L2_TYPE_IS_CAPTURE(type) \
>		(V4L2_TYPE_IS_VALID(type) && !V4L2_TYPE_IS_OUTPUT(type))
>
>This would avoid keeping the two explicit lists of OUTPUT and CAPTURE
>types.

I agree that it's better to add a V4L2_TYPE_IS_VALID(type) macro.
I will address this in V2.

Thanks.
Nas.

>
>Michael
>
>>
>>  enum v4l2_tuner_type {
>>  	V4L2_TUNER_RADIO	     = 1,
>> --
>> 2.25.1
>>
>>
>>