Hi Sakari, On Thu, Aug 15, 2019 at 04:08:49PM +0300, Sakari Ailus wrote: > On Thu, Aug 15, 2019 at 03:59:38PM +0300, Laurent Pinchart wrote: > > On Thu, Aug 15, 2019 at 10:00:25AM +0300, Sakari Ailus wrote: > > > On Wed, Aug 14, 2019 at 10:28:12PM +0200, Jacopo Mondi wrote: > > > > Add documentation for the V4L2_CID_LOCATION camera control. The newly > > > > added read-only control reports the camera device mounting position. > > > > > > > > Signed-off-by: Jacopo Mondi <jacopo@xxxxxxxxxx> > > > > --- > > > > .../media/uapi/v4l/ext-ctrls-camera.rst | 23 +++++++++++++++++++ > > > > 1 file changed, 23 insertions(+) > > > > > > > > diff --git a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst > > > > index 51c1d5c9eb00..fc0a02eee6d4 100644 > > > > --- a/Documentation/media/uapi/v4l/ext-ctrls-camera.rst > > > > +++ b/Documentation/media/uapi/v4l/ext-ctrls-camera.rst > > > > @@ -510,6 +510,29 @@ enum v4l2_scene_mode - > > > > value down. A value of zero stops the motion if one is in progress > > > > and has no effect otherwise. > > > > > > > > +``V4L2_CID_LOCATION (integer)`` > > > > + This read-only control describes the camera location by reporting its > > > > + mounting position on the device where the camera is installed. This > > > > + control is particularly meaningful for devices which have a well defined > > > > + orientation, such as phones, laptops and portable devices as the camera > > > > + location is expressed as a position relative to the device intended > > > > + usage position. In example, a camera installed on the user-facing side > > > > > > s/In/For/ > > > > > > > + of a phone device is said to be installed in the ``V4L2_LOCATION_FRONT`` > > > > + position. > > > > + > > > > + > > > > + > > > > +.. flat-table:: > > > > + :header-rows: 0 > > > > + :stub-columns: 0 > > > > + > > > > + * - ``V4L2_LOCATION_FRONT`` > > > > + - The camera device is located on the front side of the device. > > > > + * - ``V4L2_LOCATION_BACK`` > > > > + - The camera device is located on the back side of the device. > > > > + > > > > + > > > > + > > > > .. [#f1] > > > > This control may be changed to a menu control in the future, if more > > > > options are required. > > > > > > There's an effective limit of 64 for menus. ACPI has less than ten > > > different locations for a device, I think 64 will be enough here. > > > > > > So I'd be actually in favour of switching to a menu. > > > > Why ? As you explained yourself, it's a static read-only control, all it > > needs to report is a single value. > > Yes. That's true. It wasn't meant for this but it's nevertheless a > convenient API to get that information, both as integer and string. But why is that needed ? The integer seems enough to me. -- Regards, Laurent Pinchart
