| Message ID | 20240424122237.875000-10-sakari.ailus@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Generic line based metadata, without sensor API changes | expand |
Hi Sakari, Thank you for the patch. On Wed, Apr 24, 2024 at 03:22:32PM +0300, Sakari Ailus wrote: > Document S_ROUTING behaviour for different devices. > > Generally in devices that produce streams the streams are static and some > can be enabled and disabled, whereas in devices that just transport them > or write them to memory, more configurability is allowed. Document this. > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > Reviewed-by: Julien Massot <julien.massot@collabora.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > .../userspace-api/media/v4l/dev-subdev.rst | 23 +++++++++++++++++++ > 1 file changed, 23 insertions(+) > > diff --git a/Documentation/userspace-api/media/v4l/dev-subdev.rst b/Documentation/userspace-api/media/v4l/dev-subdev.rst > index b76e02e54512..0f9eda3187f3 100644 > --- a/Documentation/userspace-api/media/v4l/dev-subdev.rst > +++ b/Documentation/userspace-api/media/v4l/dev-subdev.rst > @@ -572,6 +572,29 @@ Any configurations of a stream within a pad, such as format or selections, > are independent of similar configurations on other streams. This is > subject to change in the future. > > +Device types and routing setup > +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ > + > +Different kinds of sub-devices have differing behaviour for route activation, > +depending on the hardware. In all cases, however, only routes that have the > +``V4L2_SUBDEV_STREAM_FL_ACTIVE`` flag set are active. > + > +Devices generating the streams may allow enabling and disabling some of the > +routes or have a fixed routing configuration. If the routes can be disabled, not > +declaring the routes (or declaring them without > +``VIDIOC_SUBDEV_STREAM_FL_ACTIVE`` flag set) in ``VIDIOC_SUBDEV_S_ROUTING`` will > +disable the routes. ``VIDIOC_SUBDEV_S_ROUTING`` will still return such routes > +back to the user in the routes array, with the ``V4L2_SUBDEV_STREAM_FL_ACTIVE`` > +flag unset. > + > +Devices transporting the streams almost always have more configurability with > +respect to routing. Typically any route between the sub-device's sink and source > +pads is possible, and multiple routes (usually up to certain limited number) may > +be active simultaneously. For such devices, no routes are created by the driver > +and user-created routes are fully replaced when ``VIDIOC_SUBDEV_S_ROUTING`` is > +called on the sub-device. Such newly created routes have the device's default > +configuration for format and selection rectangles. > + > Configuring streams > ^^^^^^^^^^^^^^^^^^^ >
diff --git a/Documentation/userspace-api/media/v4l/dev-subdev.rst b/Documentation/userspace-api/media/v4l/dev-subdev.rst index b76e02e54512..0f9eda3187f3 100644 --- a/Documentation/userspace-api/media/v4l/dev-subdev.rst +++ b/Documentation/userspace-api/media/v4l/dev-subdev.rst @@ -572,6 +572,29 @@ Any configurations of a stream within a pad, such as format or selections, are independent of similar configurations on other streams. This is subject to change in the future. +Device types and routing setup +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Different kinds of sub-devices have differing behaviour for route activation, +depending on the hardware. In all cases, however, only routes that have the +``V4L2_SUBDEV_STREAM_FL_ACTIVE`` flag set are active. + +Devices generating the streams may allow enabling and disabling some of the +routes or have a fixed routing configuration. If the routes can be disabled, not +declaring the routes (or declaring them without +``VIDIOC_SUBDEV_STREAM_FL_ACTIVE`` flag set) in ``VIDIOC_SUBDEV_S_ROUTING`` will +disable the routes. ``VIDIOC_SUBDEV_S_ROUTING`` will still return such routes +back to the user in the routes array, with the ``V4L2_SUBDEV_STREAM_FL_ACTIVE`` +flag unset. + +Devices transporting the streams almost always have more configurability with +respect to routing. Typically any route between the sub-device's sink and source +pads is possible, and multiple routes (usually up to certain limited number) may +be active simultaneously. For such devices, no routes are created by the driver +and user-created routes are fully replaced when ``VIDIOC_SUBDEV_S_ROUTING`` is +called on the sub-device. Such newly created routes have the device's default +configuration for format and selection rectangles. + Configuring streams ^^^^^^^^^^^^^^^^^^^