media: v4l: async: Allow binding notifiers to sub-devices
Registering a notifier has required the knowledge of struct v4l2_device
for the reason that sub-devices generally are registered to the
v4l2_device (as well as the media device, also available through
v4l2_device).
This information is not available for sub-device drivers at probe time.
What this patch does is that it allows registering notifiers without
having v4l2_device around. Instead the sub-device pointer is stored in the
notifier. Once the sub-device of the driver that registered the notifier
is registered, the notifier will gain the knowledge of the v4l2_device,
and the binding of async sub-devices from the sub-device driver's notifier
may proceed.
The complete callback of the root notifier will be called only when the
v4l2_device is available and no notifier has pending sub-devices to bind.
No complete callbacks are supported for sub-device notifiers.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
diff --git a/include/media/v4l2-async.h b/include/media/v4l2-async.h
index 68606af..17c4ac7 100644
--- a/include/media/v4l2-async.h
+++ b/include/media/v4l2-async.h
@@ -82,7 +82,8 @@ struct v4l2_async_subdev {
/**
* struct v4l2_async_notifier_operations - Asynchronous V4L2 notifier operations
* @bound: a subdevice driver has successfully probed one of the subdevices
- * @complete: all subdevices have been probed successfully
+ * @complete: All subdevices have been probed successfully. The complete
+ * callback is only executed for the root notifier.
* @unbind: a subdevice is leaving
*/
struct v4l2_async_notifier_operations {
@@ -102,7 +103,9 @@ struct v4l2_async_notifier_operations {
* @num_subdevs: number of subdevices used in the subdevs array
* @max_subdevs: number of subdevices allocated in the subdevs array
* @subdevs: array of pointers to subdevice descriptors
- * @v4l2_dev: pointer to struct v4l2_device
+ * @v4l2_dev: v4l2_device of the root notifier, NULL otherwise
+ * @sd: sub-device that registered the notifier, NULL otherwise
+ * @parent: parent notifier
* @waiting: list of struct v4l2_async_subdev, waiting for their drivers
* @done: list of struct v4l2_subdev, already probed
* @list: member in a global list of notifiers
@@ -113,6 +116,8 @@ struct v4l2_async_notifier {
unsigned int max_subdevs;
struct v4l2_async_subdev **subdevs;
struct v4l2_device *v4l2_dev;
+ struct v4l2_subdev *sd;
+ struct v4l2_async_notifier *parent;
struct list_head waiting;
struct list_head done;
struct list_head list;
@@ -128,6 +133,16 @@ int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
struct v4l2_async_notifier *notifier);
/**
+ * v4l2_async_subdev_notifier_register - registers a subdevice asynchronous
+ * notifier for a sub-device
+ *
+ * @sd: pointer to &struct v4l2_subdev
+ * @notifier: pointer to &struct v4l2_async_notifier
+ */
+int v4l2_async_subdev_notifier_register(struct v4l2_subdev *sd,
+ struct v4l2_async_notifier *notifier);
+
+/**
* v4l2_async_notifier_unregister - unregisters a subdevice asynchronous notifier
*
* @notifier: pointer to &struct v4l2_async_notifier
