Re: [PATCH v2] uvcvideo: Work around buggy Logitech C920 firmware

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On 25/03/14 23:03, Laurent Pinchart wrote:
> Hi William,
> 
> On Tuesday 25 March 2014 22:56:33 William Manley wrote:
>> On 13/03/14 12:38, William Manley wrote:
>>> The uvcvideo webcam driver exposes the v4l2 control "Exposure (Absolute)"
>>> which allows the user to control the exposure time of the webcam,
>>> essentially controlling the brightness of the received image.  By default
>>> the webcam automatically adjusts the exposure time automatically but the
>>> if you set the control "Exposure, Auto"="Manual Mode" the user can fix
>>> the exposure time.
>>>
>>> Unfortunately it seems that the Logitech C920 has a firmware bug where
>>> it will forget that it's in manual mode temporarily during initialisation.
>>> This means that the camera doesn't respect the exposure time that the user
>>> requested if they request it before starting to stream video.  They end up
>>> with a video stream which is either too bright or too dark and must reset
>>> the controls after video starts streaming.
>>>
>>> This patch introduces the quirk UVC_QUIRK_RESTORE_CTRLS_ON_INIT which
>>> causes the cached controls to be re-uploaded to the camera immediately
>>> after initialising the camera.  This quirk is applied to the C920 to work
>>> around this camera bug.
>>>
>>> Changes since patch v1:
>>>  * Introduce quirk so workaround is only applied to the C920.
>>>
>>> Signed-off-by: William Manley <will@xxxxxxxxxxxxxxxxx>
>>
>> Bump?
> 
> Sorry, I haven't had the time to handle your patch yet. I'll try to do so on 
> Thursday or Friday.

Apologies for the nagging: What's the current status?

Thanks

Will

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