Add a flag to denote immutable routes, V4L2_SUBDEV_ROUTE_FL_IMMUTABLE.
Such routes cannot be changed and they're always active.
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
---
Documentation/userspace-api/media/v4l/dev-subdev.rst | 4 +++-
.../userspace-api/media/v4l/vidioc-subdev-g-routing.rst | 5 +++++
include/uapi/linux/v4l2-subdev.h | 5 +++++
3 files changed, 13 insertions(+), 1 deletion(-)
diff --git a/Documentation/userspace-api/media/v4l/dev-subdev.rst b/Documentation/userspace-api/media/v4l/dev-subdev.rst
index de8dfd4f11a5..5c63c8c24108 100644
--- a/Documentation/userspace-api/media/v4l/dev-subdev.rst
+++ b/Documentation/userspace-api/media/v4l/dev-subdev.rst
@@ -572,7 +572,9 @@ internal pad always has a single stream only (0).
Routes from an internal sink pad to an external source pad are typically not
modifiable but they can be activated and deactivated using the
:ref:`V4L2_SUBDEV_ROUTE_FL_ACTIVE <v4l2-subdev-routing-flags>` flag, depending
-on driver capabilities.
+on driver capabilities. The :ref:`V4L2_SUBDEV_ROUTE_FL_IMMUTABLE
+<v4l2-subdev-routing-flags>` flag indicates that the
+``V4L2_SUBDEV_ROUTE_FLAG_ACTIVE`` of the route may not be unset.
Interaction between routes, streams, formats and selections
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
diff --git a/Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst
index 88df7bf80b00..c0f6d49cac6d 100644
--- a/Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst
+++ b/Documentation/userspace-api/media/v4l/vidioc-subdev-g-routing.rst
@@ -150,6 +150,11 @@ Also ``VIDIOC_SUBDEV_S_ROUTING`` may return more route than the user provided in
* - V4L2_SUBDEV_ROUTE_FL_ACTIVE
- 0x0001
- The route is enabled. Set by applications.
+ * - V4L2_SUBDEV_ROUTE_FL_IMMUTABLE
+ - 0x0002
+ - The route is immutable. Set by the driver. Indicates that the
+ ``V4L2_SUBDEV_ROUTE_FL_ACTIVE`` flag of an immutable route may not be
+ unset.
Return Value
============
diff --git a/include/uapi/linux/v4l2-subdev.h b/include/uapi/linux/v4l2-subdev.h
index 6a39128d0606..c6f1228d43b1 100644
--- a/include/uapi/linux/v4l2-subdev.h
+++ b/include/uapi/linux/v4l2-subdev.h
@@ -204,6 +204,11 @@ struct v4l2_subdev_capability {
* on a video node.
*/
#define V4L2_SUBDEV_ROUTE_FL_ACTIVE (1U << 0)
+/*
+ * Is the route immutable. The ACTIVE flag of an immutable route may not be
+ * changed.
+ */
+#define V4L2_SUBDEV_ROUTE_FL_IMMUTABLE (1U << 1)
/**
* struct v4l2_subdev_route - A route inside a subdev
--
2.39.2
