Re: [PATCH v2 1/2] media: v4l2-ctrl: Add control for VP9 profile

[Hans Verkuil]

On 11/06/18 08:44, Keiichi Watanabe wrote:
> Hi, Hans.
> Thank you for the review.
> Your idea sounds good.
> 
> However, I think that changing V4L2_CID_MPEG_VIDEO_VPX_PROFILE to an enum
> breaks both of s5p-mfc and venus drivers.  This is because they call
> 'v4l2_ctrl_new_std' for it.  For menu controls,
> 'v4l2_ctrl_new_std_menu' must be used.
> 
> https://elixir.bootlin.com/linux/latest/source/drivers/media/platform/s5p-mfc/s5p_mfc_enc.c#L2678
> https://elixir.bootlin.com/linux/latest/source/drivers/media/platform/qcom/venus/vdec_ctrls.c#L133
> 
> I can fix them within the commit for adding VP8_PROFILE control, but
> cannot confirm that it works on real devices since I don't have them.
> What should I do?

Fix it in both drivers with a Cc to stanimir.varbanov@xxxxxxxxxx (venus) and
s.nawrocki@xxxxxxxxxxx (s5p) to let them test/ack the patch.

Venus is no problem, the s5p driver can decide to keep the old INT control
since it has been in use for such a long time, but that is up to Sylwester to
decide.

Regards,

	Hans

> 
> Best regards,
> Keiichi
> On Fri, Jun 8, 2018 at 10:00 PM Nicolas Dufresne <nicolas@xxxxxxxxxxxx> wrote:
>>
>>
>>
>> Le ven. 8 juin 2018 08:56, Stanimir Varbanov <stanimir.varbanov@xxxxxxxxxx> a Ãcrit :
>>>
>>> Hi Hans,
>>>
>>> On 06/08/2018 12:29 PM, Hans Verkuil wrote:
>>>> On 05/30/2018 09:16 AM, Keiichi Watanabe wrote:
>>>>> Add a new control V4L2_CID_MPEG_VIDEO_VP9_PROFILE for selecting desired
>>>>> profile for VP9 encoder and querying for supported profiles by VP9 encoder
>>>>> or decoder.
>>>>>
>>>>> An existing control V4L2_CID_MPEG_VIDEO_VPX_PROFILE cannot be
>>>>> used for querying since it is not a menu control but an integer
>>>>> control, which cannot return an arbitrary set of supported profiles.
>>>>>
>>>>> The new control V4L2_CID_MPEG_VIDEO_VP9_PROFILE is a menu control as
>>>>> with controls for other codec profiles. (e.g. H264)
>>>>
>>>> Please ignore my reply to patch 2/2. I looked at this a bit more and what you
>>>> should do is to change the type of V4L2_CID_MPEG_VIDEO_VPX_PROFILE to enum.
>>>>
>>>> All other codec profile controls are all enums, so the fact that VPX_PROFILE
>>>> isn't is a bug. Changing the type should not cause any problems since the same
>>>> control value is used when you set the control.
>>>>
>>>> Sylwester: I see that s5p-mfc uses this control, but it is explicitly added
>>>> as an integer type control, so the s5p-mfc driver should not be affected by
>>>> changing the type of this control.
>>>>
>>>> Stanimir: this will slightly change the venus driver, but since it is a very
>>>> recent driver I think we can get away with changing the core type of the
>>>> VPX_PROFILE control. I think that's better than ending up with two controls
>>>> that do the same thing.
>>>
>>> I agree. Actually the changes shouldn't be so much in venus driver.
>>
>>
>> Also fine on userspace side, since profiles enumeration isn't implemented yet in FFMPEG, GStreamer, Chrome
>>
>>
>>>
>>> --
>>> regards,
>>> Stan