2 files changed, 113 insertions, 0 deletions

diff --git a/include/media/v4l2-async.h b/include/media/v4l2-async.h
new file mode 100644
index 000000000000..c3ec6ac75f7e
--- /dev/null
+++ b/include/media/v4l2-async.h
@@ -0,0 +1,105 @@
+/*
+ * V4L2 asynchronous subdevice registration API
+ *
+ * Copyright (C) 2012-2013, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef V4L2_ASYNC_H
+#define V4L2_ASYNC_H
+
+#include <linux/list.h>
+#include <linux/mutex.h>
+
+struct device;
+struct v4l2_device;
+struct v4l2_subdev;
+struct v4l2_async_notifier;
+
+/* A random max subdevice number, used to allocate an array on stack */
+#define V4L2_MAX_SUBDEVS 128U
+
+enum v4l2_async_bus_type {
+        V4L2_ASYNC_BUS_CUSTOM,
+        V4L2_ASYNC_BUS_PLATFORM,
+        V4L2_ASYNC_BUS_I2C,
+};
+
+/**
+ * struct v4l2_async_subdev - sub-device descriptor, as known to a bridge
+ * @bus_type:   subdevice bus type to select the appropriate matching method
+ * @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
+ */
+struct v4l2_async_subdev {
+        enum v4l2_async_bus_type bus_type;
+        union {
+                struct {
+                        const char *name;
+                } platform;
+                struct {
+                        int adapter_id;
+                        unsigned short address;
+                } i2c;
+                struct {
+                        bool (*match)(struct device *,
+                                      struct v4l2_async_subdev *);
+                        void *priv;
+                } custom;
+        } match;
+
+        /* v4l2-async core private: not to be used by drivers */
+        struct list_head list;
+};
+
+/**
+ * v4l2_async_subdev_list - provided by subdevices
+ * @list:       links struct v4l2_async_subdev_list objects to a global list
+ *              before probing, and onto notifier->done after probing
+ * @asd:        pointer to respective struct v4l2_async_subdev
+ * @notifier:   pointer to managing notifier
+ */
+struct v4l2_async_subdev_list {
+        struct list_head list;
+        struct v4l2_async_subdev *asd;
+        struct v4l2_async_notifier *notifier;
+};
+
+/**
+ * v4l2_async_notifier - v4l2_device notifier data
+ * @num_subdevs:number of subdevices
+ * @subdev:     array of pointers to subdevice descriptors
+ * @v4l2_dev:   pointer to struct v4l2_device
+ * @waiting:    list of struct v4l2_async_subdev, waiting for their drivers
+ * @done:       list of struct v4l2_async_subdev_list, 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 {
+        unsigned int num_subdevs;
+        struct v4l2_async_subdev **subdev;
+        struct v4l2_device *v4l2_dev;
+        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);
+};
+
+int v4l2_async_notifier_register(struct v4l2_device *v4l2_dev,
+                                 struct v4l2_async_notifier *notifier);
+void v4l2_async_notifier_unregister(struct v4l2_async_notifier *notifier);
+int v4l2_async_register_subdev(struct v4l2_subdev *sd);
+void v4l2_async_unregister_subdev(struct v4l2_subdev *sd);
+#endif
diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h
index 5fbb266405f9..3250cc5e7925 100644
--- a/include/media/v4l2-subdev.h
+++ b/include/media/v4l2-subdev.h
@@ -24,6 +24,7 @@
 #include <linux/types.h>
 #include <linux/v4l2-subdev.h>
 #include <media/media-entity.h>
+#include <media/v4l2-async.h>
 #include <media/v4l2-common.h>
 #include <media/v4l2-dev.h>
 #include <media/v4l2-fh.h>
@@ -585,8 +586,15 @@ struct v4l2_subdev {
         struct video_device *devnode;
         /* pointer to the physical device, if any */
         struct device *dev;
+        struct v4l2_async_subdev_list asdl;
 };
 
+static inline struct v4l2_subdev *v4l2_async_to_subdev(
+                        struct v4l2_async_subdev_list *asdl)
+{
+        return container_of(asdl, struct v4l2_subdev, asdl);
+}
+
 #define media_entity_to_v4l2_subdev(ent) \
         container_of(ent, struct v4l2_subdev, entity)
 #define vdev_to_v4l2_subdev(vdev) \