Hi David, Thanks for the patch. Cc'ing Laurent, too. On Mon, May 17, 2021 at 11:02:40AM +0100, David Plowman wrote: > Add documentation for each of the controls > > V4L2_CID_NOTIFY_GAIN_RED > V4L2_CID_NOTIFY_GAIN_GREENR > V4L2_CID_NOTIFY_GAIN_BLUE > V4L2_CID_NOTIFY_GAIN_GREENB > > These controls are required by sensors that need to know what colour > gains will be applied to pixels by downstream processing (such as by > an ISP), though the sensor does not apply these gains itself. > > Signed-off-by: David Plowman <david.plowman@xxxxxxxxxxxxxxx> > --- > .../media/v4l/ext-ctrls-image-source.rst | 28 +++++++++++++++++++ > 1 file changed, 28 insertions(+) > > diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst > index de43f5c8486d..f824d6c36ae8 100644 > --- a/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst > +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-image-source.rst > @@ -72,3 +72,31 @@ Image Source Control IDs > * - __u32 > - ``height`` > - Height of the area. > + > +``V4L2_CID_NOTIFY_GAIN_RED (integer)`` > + Notify the sensor what gain will be applied to red pixels by the > + subsequent processing (such as by an ISP). The sensor is merely > + informed of this value in case it performs processing that requires > + it, but it is not applied to the output pixels themselves. The > + units are determined by the sensor driver. I wonder if this should say the default value should reflect gain of 1. It probably wouldn't hurt at least. > + > +``V4L2_CID_NOTIFY_GAIN_GREENR (integer)`` > + Notify the sensor what gain will be applied to green pixels (on > + red rows) by subsequent processing (such as by an ISP). The sensor > + is merely informed of this value in case it performs processing > + that requires it, but it is not applied to the output pixels > + themselves. The units are determined by the sensor driver. > + > +``V4L2_CID_NOTIFY_GAIN_BLUE (integer)`` > + Notify the sensor what gain will be applied to blue pixels by the > + subsequent processing (such as by an ISP). The sensor is merely > + informed of this value in case it performs processing that requires > + it, but it is not applied to the output pixels themselves. The > + units are determined by the sensor driver. > + > +``V4L2_CID_NOTIFY_GAIN_GREENB (integer)`` > + Notify the sensor what gain will be applied to green pixels (on > + blue rows) by subsequent processing (such as by an ISP). The sensor > + is merely informed of this value in case it performs processing > + that requires it, but it is not applied to the output pixels > + themselves. The units are determined by the sensor driver. -- Kind regards, Sakari Ailus
