Merge tag 'for-linus-20171120' of git://git.infradead.org/linux-mtd

[mirror_ubuntu-bionic-kernel.git] / include / media / v4l2-async.h

diff --git a/include/media/v4l2-async.h b/include/media/v4l2-async.h
index c69d8c8a66d0093ad2f5a542e177fc45d674f14f..6152434cbe827196949d55f420d69da6999acbcb 100644 (file)
--- a/include/media/v4l2-async.h
+++ b/include/media/v4l2-async.h
@@ -50,6 +50,10 @@ enum v4l2_async_match_type {
  * @match:     union of per-bus type matching data sets
  * @list:      used to link struct v4l2_async_subdev objects, waiting to be
  *             probed, to a notifier->waiting list
+ *
+ * When this struct is used as a member in a driver specific struct,
+ * the driver specific struct shall contain the &struct
+ * v4l2_async_subdev as its first member.
  */
 struct v4l2_async_subdev {
        enum v4l2_async_match_type match_type;
@@ -75,33 +79,48 @@ struct v4l2_async_subdev {
        struct list_head list;
 };
 
+/**
+ * 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. The complete
+ *             callback is only executed for the root notifier.
+ * @unbind:    a subdevice is leaving
+ */
+struct v4l2_async_notifier_operations {
+       int (*bound)(struct v4l2_async_notifier *notifier,
+                    struct v4l2_subdev *subdev,
+                    struct v4l2_async_subdev *asd);
+       int (*complete)(struct v4l2_async_notifier *notifier);
+       void (*unbind)(struct v4l2_async_notifier *notifier,
+                      struct v4l2_subdev *subdev,
+                      struct v4l2_async_subdev *asd);
+};
+
 /**
  * struct v4l2_async_notifier - v4l2_device notifier data
  *
- * @num_subdevs: number of subdevices
+ * @ops:       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
- * @bound:     a subdevice driver has successfully probed one of subdevices
- * @complete:  all subdevices have been probed successfully
- * @unbind:    a subdevice is leaving
  */
 struct v4l2_async_notifier {
+       const struct v4l2_async_notifier_operations *ops;
        unsigned int num_subdevs;
+       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;
-       int (*bound)(struct v4l2_async_notifier *notifier,
-                    struct v4l2_subdev *subdev,
-                    struct v4l2_async_subdev *asd);
-       int (*complete)(struct v4l2_async_notifier *notifier);
-       void (*unbind)(struct v4l2_async_notifier *notifier,
-                      struct v4l2_subdev *subdev,
-                      struct v4l2_async_subdev *asd);
 };
 
 /**
@@ -113,6 +132,16 @@ struct v4l2_async_notifier {
 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
  *
@@ -120,6 +149,22 @@ int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
  */
 void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier);
 
+/**
+ * v4l2_async_notifier_cleanup - clean up notifier resources
+ * @notifier: the notifier the resources of which are to be cleaned up
+ *
+ * Release memory resources related to a notifier, including the async
+ * sub-devices allocated for the purposes of the notifier but not the notifier
+ * itself. The user is responsible for calling this function to clean up the
+ * notifier after calling @v4l2_async_notifier_parse_fwnode_endpoints or
+ * @v4l2_fwnode_reference_parse_sensor_common.
+ *
+ * There is no harm from calling v4l2_async_notifier_cleanup in other
+ * cases as long as its memory has been zeroed after it has been
+ * allocated.
+ */
+void v4l2_async_notifier_cleanup(struct v4l2_async_notifier *notifier);
+
 /**
  * v4l2_async_register_subdev - registers a sub-device to the asynchronous
  *     subdevice framework
@@ -128,6 +173,28 @@ void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier);
  */
 int v4l2_async_register_subdev(struct v4l2_subdev *sd);
 
+/**
+ * v4l2_async_register_subdev_sensor_common - registers a sensor sub-device to
+ *                                           the asynchronous sub-device
+ *                                           framework and parse set up common
+ *                                           sensor related devices
+ *
+ * @sd: pointer to struct &v4l2_subdev
+ *
+ * This function is just like v4l2_async_register_subdev() with the exception
+ * that calling it will also parse firmware interfaces for remote references
+ * using v4l2_async_notifier_parse_fwnode_sensor_common() and registers the
+ * async sub-devices. The sub-device is similarly unregistered by calling
+ * v4l2_async_unregister_subdev().
+ *
+ * While registered, the subdev module is marked as in-use.
+ *
+ * An error is returned if the module is no longer loaded on any attempts
+ * to register it.
+ */
+int __must_check v4l2_async_register_subdev_sensor_common(
+       struct v4l2_subdev *sd);
+
 /**
  * v4l2_async_unregister_subdev - unregisters a sub-device to the asynchronous
  *     subdevice framework