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
Acked-by: Hans Verkuil
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()
> ` or
> :ref:`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() ` 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.
>
