Re: [PATCH] media/v4l2-ctrls: Always run s_ctrl on volatile ctrls

From: Hans Verkuil
Date: Tue Feb 17 2015 - 07:24:19 EST

On 02/17/15 13:21, Ricardo Ribalda Delgado wrote:
> Hello Hans
> On Tue, Feb 17, 2015 at 1:03 PM, Hans Verkuil <hverkuil@xxxxxxxxx> wrote:
>> Should be done after the 'ctrl == NULL' check.
> Good catch. Fixed on v2
>>> if (ctrl == NULL)
>>> continue;
>> There is one more change that has to be made: setting a volatile control
>> should never generate a V4L2_EVENT_CTRL_CH_VALUE event since that makes
>> no sense. The way to prevent that is to ensure that ctrl->has_changed is
>> always false for volatile controls. The new_to_cur function looks at that
>> field to decide whether to send an event.
>> The documentation should also be updated: that of V4L2_CTRL_FLAG_VOLATILE
> I can do this also if you want. It has been a while without
> contributing to media :)

Yes, please. I can't accept the patch without these other changes anyway :-)


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