On 11/21/2018 06:33 PM, Sakari Ailus wrote: > Document that changing the frame interval has no effect on frame size. > While this was the assumption in the API, it was not documented as such. > > Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> Acked-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> Thanks! Hans > --- > Documentation/media/uapi/v4l/vidioc-g-parm.rst | 3 +++ > Documentation/media/uapi/v4l/vidioc-subdev-g-frame-interval.rst | 3 +++ > 2 files changed, 6 insertions(+) > > diff --git a/Documentation/media/uapi/v4l/vidioc-g-parm.rst b/Documentation/media/uapi/v4l/vidioc-g-parm.rst > index e831fa5512f0..c31585a7701b 100644 > --- a/Documentation/media/uapi/v4l/vidioc-g-parm.rst > +++ b/Documentation/media/uapi/v4l/vidioc-g-parm.rst > @@ -42,6 +42,9 @@ side. This is especially useful when using the :ref:`read() <func-read>` or > :ref:`write() <func-write>`, which are not augmented by timestamps or sequence > counters, and to avoid unnecessary data copying. > > +Changing the frame interval shall never change the format. Changing the > +format, on the other hand, may change the frame interval. > + > Further these ioctls can be used to determine the number of buffers used > internally by a driver in read/write mode. For implications see the > section discussing the :ref:`read() <func-read>` function. > diff --git a/Documentation/media/uapi/v4l/vidioc-subdev-g-frame-interval.rst b/Documentation/media/uapi/v4l/vidioc-subdev-g-frame-interval.rst > index 5af0a7179941..f889c20f231c 100644 > --- a/Documentation/media/uapi/v4l/vidioc-subdev-g-frame-interval.rst > +++ b/Documentation/media/uapi/v4l/vidioc-subdev-g-frame-interval.rst > @@ -63,6 +63,9 @@ doesn't match the device capabilities. They must instead modify the > interval to match what the hardware can provide. The modified interval > should be as close as possible to the original request. > > +Changing the frame interval shall never change the format. Changing the > +format, on the other hand, may change the frame interval. > + > Sub-devices that support the frame interval ioctls should implement them > on a single pad only. Their behaviour when supported on multiple pads of > the same sub-device is not defined. >
