Hi Laurent, On 6/6/23 12:36, Laurent Pinchart wrote: > Hi Michael, > > Thank you for the patch. > > On Tue, Apr 25, 2023 at 11:45:12AM +0200, Michael Riesch wrote: >> The control V4L2_CID_FOCUS_RELATIVE only makes sense if the device cannot >> handle absolute focal point positioning with V4L2_CID_FOCUS_ABSOLUTE. >> Clarify this in the documentation. >> >> Signed-off-by: Michael Riesch <michael.riesch@xxxxxxxxxxxxxx> >> --- >> Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst >> index df29150dce7b..42cf4c3cda0c 100644 >> --- a/Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst >> +++ b/Documentation/userspace-api/media/v4l/ext-ctrls-camera.rst >> @@ -147,7 +147,9 @@ enum v4l2_exposure_metering - >> This control moves the focal point of the camera by the specified >> amount. The unit is undefined. Positive values move the focus closer >> to the camera, negative values towards infinity. This is a >> - write-only control. >> + write-only control. It should be implemented only if the device cannot >> + handle absolute values. >> + > > Extra blank line. Will fix that. > I don't think this is right. The control was added for the UVC driver, > and there are devices that implement both absolute and relative focus. I am by no means an expert here and just following Sakari's suggestion here (see [0]). I can drop the patch, leave it as-is, or modify it. Whatever makes sense to you guys. But maybe I should leave this to someone more knowledgeable in this area and drop the patch from my series. The changes above are completely orthogonal to my work. Best regards, Michael > >> >> ``V4L2_CID_FOCUS_AUTO (boolean)`` >> Enables continuous automatic focus adjustments. The effect of manual >> > [0] https://lore.kernel.org/all/ZDbChgZJHVaaX3%2Fx@kekkonen.localdomain/
