1 files changed, 234 insertions, 0 deletions

diff --git a/extras/recipes-kernel/linux/linux-omap/media/0018-v4l-Make-video_device-inherit-from-media_entity.patch b/extras/recipes-kernel/linux/linux-omap/media/0018-v4l-Make-video_device-inherit-from-media_entity.patch
new file mode 100644
index 00000000..6417d1db
--- /dev/null
+++ b/extras/recipes-kernel/linux/linux-omap/media/0018-v4l-Make-video_device-inherit-from-media_entity.patch
@@ -0,0 +1,234 @@
+From e31cb57c733341b49256a47f086fa4cc1c1c56ac Mon Sep 17 00:00:00 2001
+From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+Date: Wed, 9 Dec 2009 12:40:10 +0100
+Subject: [PATCH 18/43] v4l: Make video_device inherit from media_entity
+
+V4L2 devices are media entities. As such they need to inherit from
+(include) the media_entity structure.
+
+When registering/unregistering the device, the media entity is
+automatically registered/unregistered. The entity is acquired on device
+open and released on device close.
+
+Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
+---
+ Documentation/video4linux/v4l2-framework.txt |   38 ++++++++++++++++++--
+ drivers/media/video/v4l2-dev.c               |   49 +++++++++++++++++++++++--
+ include/media/v4l2-dev.h                     |    7 ++++
+ 3 files changed, 87 insertions(+), 7 deletions(-)
+
+diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt
+index aeb2a22..f231bc2 100644
+--- a/Documentation/video4linux/v4l2-framework.txt
++++ b/Documentation/video4linux/v4l2-framework.txt
+@@ -71,6 +71,10 @@ sub-device instances, the video_device struct stores V4L2 device node data
+ and in the future a v4l2_fh struct will keep track of filehandle instances
+ (this is not yet implemented).
+ 
++The V4L2 framework also optionally integrates with the media framework. If a
++driver sets the struct v4l2_device mdev field, sub-devices and video nodes
++will automatically appear in the media framework as entities.
++
+ 
+ struct v4l2_device
+ ------------------
+@@ -84,11 +88,14 @@ You must register the device instance:
+        v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
+ 
+ Registration will initialize the v4l2_device struct. If the dev->driver_data
+-field is NULL, it will be linked to v4l2_dev. Drivers that use the media
+-device framework in addition to the V4L2 framework need to set
++field is NULL, it will be linked to v4l2_dev.
++
++Drivers that want integration with the media device framework need to set
+ dev->driver_data manually to point to the driver-specific device structure
+ that embed the struct v4l2_device instance. This is achieved by a
+-dev_set_drvdata() call before registering the V4L2 device instance.
++dev_set_drvdata() call before registering the V4L2 device instance. They must
++also set the struct v4l2_device mdev field to point to a properly initialized
++and registered media_device instance.
+ 
+ If v4l2_dev->name is empty then it will be set to a value derived from dev
+ (driver name followed by the bus_id, to be precise). If you set it up before
+@@ -532,6 +539,21 @@ If you use v4l2_ioctl_ops, then you should set either .unlocked_ioctl or
+ The v4l2_file_operations struct is a subset of file_operations. The main
+ difference is that the inode argument is omitted since it is never used.
+ 
++If integration with the media framework is needed, you must initialize the
++media_entity struct embedded in the video_device struct (entity field) by
++calling media_entity_init():
++
++       struct media_pad *pad = &my_vdev->pad;
++       int err;
++
++       err = media_entity_init(&vdev->entity, 1, pad, 0);
++
++The pads array must have been previously initialized. There is no need to
++manually set the struct media_entity type and name fields.
++
++A reference to the entity will be automatically acquired/released when the
++video device is opened/closed.
++
+ v4l2_file_operations and locking
+ --------------------------------
+ 
+@@ -561,6 +583,9 @@ for you.
+                return err;
+        }
+ 
++If the v4l2_device parent device has a non-NULL mdev field, the video device
++entity will be automatically registered with the media device.
++
+ Which device is registered depends on the type argument. The following
+ types exist:
+ 
+@@ -636,6 +661,13 @@ release, of course) will return an error as well.
+ When the last user of the video device node exits, then the vdev->release()
+ callback is called and you can do the final cleanup there.
+ 
++Don't forget to cleanup the media entity associated with the video device if
++it has been initialized:
++
++       media_entity_cleanup(&vdev->entity);
++
++This can be done from the release callback.
++
+ 
+ video_device helper functions
+ -----------------------------
+diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
+index f22bd41..f91348f 100644
+--- a/drivers/media/video/v4l2-dev.c
++++ b/drivers/media/video/v4l2-dev.c
+@@ -303,6 +303,9 @@ static int v4l2_mmap(struct file *filp, struct vm_area_struct *vm)
+ static int v4l2_open(struct inode *inode, struct file *filp)
+ {
+        struct video_device *vdev;
++#if defined(CONFIG_MEDIA_CONTROLLER)
++       struct media_entity *entity = NULL;
++#endif
+        int ret = 0;
+ 
+        /* Check if the video device is available */
+@@ -316,6 +319,16 @@ static int v4l2_open(struct inode *inode, struct file *filp)
+        /* and increase the device refcount */
+        video_get(vdev);
+        mutex_unlock(&videodev_lock);
++#if defined(CONFIG_MEDIA_CONTROLLER)
++       if (vdev->v4l2_dev && vdev->v4l2_dev->mdev) {
++               entity = media_entity_get(&vdev->entity);
++               if (!entity) {
++                       ret = -EBUSY;
++                       video_put(vdev);
++                       return ret;
++               }
++       }
++#endif
+        if (vdev->fops->open) {
+                if (vdev->lock && mutex_lock_interruptible(vdev->lock)) {
+                        ret = -ERESTARTSYS;
+@@ -331,8 +344,13 @@ static int v4l2_open(struct inode *inode, struct file *filp)
+ 
+ err:
+        /* decrease the refcount in case of an error */
+-       if (ret)
++       if (ret) {
++#if defined(CONFIG_MEDIA_CONTROLLER)
++               if (vdev->v4l2_dev && vdev->v4l2_dev->mdev)
++                       media_entity_put(entity);
++#endif
+                video_put(vdev);
++       }
+        return ret;
+ }
+ 
+@@ -349,7 +367,10 @@ static int v4l2_release(struct inode *inode, struct file *filp)
+                if (vdev->lock)
+                        mutex_unlock(vdev->lock);
+        }
+-
++#if defined(CONFIG_MEDIA_CONTROLLER)
++       if (vdev->v4l2_dev && vdev->v4l2_dev->mdev)
++               media_entity_put(&vdev->entity);
++#endif
+        /* decrease the refcount unconditionally since the release()
+           return value is ignored. */
+        video_put(vdev);
+@@ -586,12 +607,27 @@ int __video_register_device(struct video_device *vdev, int type, int nr,
+        if (nr != -1 && nr != vdev->num && warn_if_nr_in_use)
+                printk(KERN_WARNING "%s: requested %s%d, got %s\n", __func__,
+                        name_base, nr, video_device_node_name(vdev));
+-
+-       /* Part 5: Activate this minor. The char device can now be used. */
++#if defined(CONFIG_MEDIA_CONTROLLER)
++       /* Part 5: Register the entity. */
++       if (vdev->v4l2_dev && vdev->v4l2_dev->mdev) {
++               vdev->entity.type = MEDIA_ENT_T_DEVNODE_V4L;
++               vdev->entity.name = vdev->name;
++               vdev->entity.v4l.major = VIDEO_MAJOR;
++               vdev->entity.v4l.minor = vdev->minor;
++               ret = media_device_register_entity(vdev->v4l2_dev->mdev,
++                       &vdev->entity);
++               if (ret < 0)
++                       printk(KERN_WARNING
++                              "%s: media_device_register_entity failed\n",
++                              __func__);
++       }
++#endif
++       /* Part 6: Activate this minor. The char device can now be used. */
+        set_bit(V4L2_FL_REGISTERED, &vdev->flags);
+        mutex_lock(&videodev_lock);
+        video_device[vdev->minor] = vdev;
+        mutex_unlock(&videodev_lock);
++
+        return 0;
+ 
+ cleanup:
+@@ -619,6 +655,11 @@ void video_unregister_device(struct video_device *vdev)
+        if (!vdev || !video_is_registered(vdev))
+                return;
+ 
++#if defined(CONFIG_MEDIA_CONTROLLER)
++       if (vdev->v4l2_dev && vdev->v4l2_dev->mdev)
++               media_device_unregister_entity(&vdev->entity);
++#endif
++
+        mutex_lock(&videodev_lock);
+        /* This must be in a critical section to prevent a race with v4l2_open.
+         * Once this bit has been cleared video_get may never be called again.
+diff --git a/include/media/v4l2-dev.h b/include/media/v4l2-dev.h
+index 4fe6831..51b2c51 100644
+--- a/include/media/v4l2-dev.h
++++ b/include/media/v4l2-dev.h
+@@ -16,6 +16,8 @@
+ #include <linux/mutex.h>
+ #include <linux/videodev2.h>
+ 
++#include <media/media-entity.h>
++
+ #define VIDEO_MAJOR    81
+ 
+ #define VFL_TYPE_GRABBER       0
+@@ -55,6 +57,9 @@ struct v4l2_file_operations {
+ 
+ struct video_device
+ {
++#if defined(CONFIG_MEDIA_CONTROLLER)
++       struct media_entity entity;
++#endif
+        /* device ops */
+        const struct v4l2_file_operations *fops;
+ 
+@@ -100,6 +105,8 @@ struct video_device
+        struct mutex *lock;
+ };
+ 
++#define media_entity_to_video_device(entity) \
++       container_of(entity, struct video_device, entity)
+ /* dev to video-device */
+ #define to_video_device(cd) container_of(cd, struct video_device, dev)
+ 
+-- 
+1.6.6.1
+