Re: [PATCH v2 3/3] media: uvcvideo: fix up missing AUTO_UPDATE on the OBSBOT Tiny 2

[Ricardo Ribalda]

Hi Michael

On Mon, 28 Sept 2026 at 00:06, Michael Jordan <jordan.mymail@xxxxxxxxx> wrote:
>
> Hi Ricardo,
>
> On Wed, 2 Sep 2026 08:34:34 +0200, Ricardo Ribalda <ribalda@xxxxxxxxxxxx> wrote:
> > Reviewed-by: Ricardo Ribalda <ribalda@xxxxxxxxxxxx>
>
> Thanks for the reviews on v2.
>
> I have a question about how to handle a second device. I now have an
> OBSBOT Tail 2 (3564:fefc) and it has the same defect as the Tiny 2.
>
> Its GET_INFO bytes match the Tiny 2 control for control:
>
>   CT_PANTILT_ABSOLUTE   0x03
>   CT_PANTILT_RELATIVE   0x03
>   CT_ZOOM_ABSOLUTE      0x03
>   CT_ZOOM_RELATIVE      0x0f
>   CT_ROLL_ABSOLUTE      0x01
>
> Without a fixup entry, pan_absolute reads back the commanded target the
> moment it is written. With entries for 3564:fefc on top of v2, all three
> controls report the live value on GET_CUR, both during a commanded move
> and when the camera changes them on its own:
>
> - pan/tilt position and pan/tilt speed follow the gimbal under the
>   camera's subject tracking, with the host issuing no requests;
> - zoom follows a zoom change made at the camera.
>
> I checked the other AUTO_UPDATE controls the same way as for the Tiny 2.
> White balance and focus only echo the last SET_CUR. Exposure time reports
> live values until the host writes a manual exposure once, and from then
> on echoes that value, across a power cycle. I would leave all of those
> alone, as on the Tiny 2.
>
> So the change is three more table entries, identical to the Tiny 2 ones
> apart from the product ID. v2 still applies cleanly to media/next as of
> 2dcdfb625c3b, so nothing else forces a respin.
>
> Which would you prefer?
>
>  a) a v3 with the Tail 2 entries folded into 3/3;
>  b) a v3 with the Tail 2 entries as a new 4/4, leaving 1-3 as reviewed;
>  c) leave v2 as it is, and send the Tail 2 entries as a follow-up patch
>     once v2 is applied.

I prefer b) because c) cannot be tested by media-ci.

>
> I lean towards (c), so that a reviewed series is not disturbed, but I am
> happy to do whichever is easiest for you and Laurent. In any of the three
> I will include the Tail 2 lsusb -v output.

BTW, I am curious, did you hear anything back from OBSBOT?
Could you also report this to them?

Thanks!

>
> Thanks,
> Michael



-- 
Ricardo Ribalda