V4L2 subdevices are media entities. As such they need to inherit from (include) the media_entity structure.
When registering/unregistering the subdevice, 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 | 23 ++++++++++++++ drivers/media/video/v4l2-device.c | 39 ++++++++++++++++++++---- drivers/media/video/v4l2-subdev.c | 41 ++++++++++++++++++++++++- include/media/v4l2-subdev.h | 10 ++++++ 4 files changed, 104 insertions(+), 9 deletions(-)
diff --git a/Documentation/video4linux/v4l2-framework.txt b/Documentation/video4linux/v4l2-framework.txt index f231bc20..d0fb880 100644 --- a/Documentation/video4linux/v4l2-framework.txt +++ b/Documentation/video4linux/v4l2-framework.txt @@ -268,6 +268,26 @@ A sub-device driver initializes the v4l2_subdev struct using: Afterwards you need to initialize subdev->name with a unique name and set the module owner. This is done for you if you use the i2c helper functions.
+If integration with the media framework is needed, you must initialize the +media_entity struct embedded in the v4l2_subdev struct (entity field) by +calling media_entity_init(): + + struct media_pad *pads = &my_sd->pads; + int err; + + err = media_entity_init(&sd->entity, npads, pads, 0); + +The pads array must have been previously initialized. There is no need to +manually set the struct media_entity type and name fields, but the revision +field must be initialized if needed. + +A reference to the entity will be automatically acquired/released when the +subdev device node (if any) is opened/closed. + +Don't forget to cleanup the media entity before the sub-device is destroyed: + + media_entity_cleanup(&sd->entity); + A device (bridge) driver needs to register the v4l2_subdev with the v4l2_device:
@@ -277,6 +297,9 @@ This can fail if the subdev module disappeared before it could be registered. After this function was called successfully the subdev->dev field points to the v4l2_device.
+If the v4l2_device parent device has a non-NULL mdev field, the sub-device +entity will be automatically registered with the media device. + You can unregister a sub-device using:
v4l2_device_unregister_subdev(sd); diff --git a/drivers/media/video/v4l2-device.c b/drivers/media/video/v4l2-device.c index 8447466..7ac4d0f 100644 --- a/drivers/media/video/v4l2-device.c +++ b/drivers/media/video/v4l2-device.c @@ -115,8 +115,11 @@ void v4l2_device_unregister(struct v4l2_device *v4l2_dev) EXPORT_SYMBOL_GPL(v4l2_device_unregister);
int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, - struct v4l2_subdev *sd) + struct v4l2_subdev *sd) { +#if defined(CONFIG_MEDIA_CONTROLLER) + struct media_entity *entity = &sd->entity; +#endif struct video_device *vdev; int err;
@@ -134,7 +137,16 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler); if (err) return err; - +#if defined(CONFIG_MEDIA_CONTROLLER) + /* Register the entity. */ + if (v4l2_dev->mdev) { + err = media_device_register_entity(v4l2_dev->mdev, entity); + if (err < 0) { + module_put(sd->owner); + return err; + } + } +#endif sd->v4l2_dev = v4l2_dev; spin_lock(&v4l2_dev->lock); list_add_tail(&sd->list, &v4l2_dev->subdevs); @@ -149,26 +161,39 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, if (sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE) { err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1, sd->owner); - if (err < 0) + if (err < 0) { v4l2_device_unregister_subdev(sd); + return err; + } } - - return err; +#if defined(CONFIG_MEDIA_CONTROLLER) + entity->v4l.major = VIDEO_MAJOR; + entity->v4l.minor = vdev->minor; +#endif + return 0; } EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) { + struct v4l2_device *v4l2_dev; + /* return if it isn't registered */ if (sd == NULL || sd->v4l2_dev == NULL) return;
- spin_lock(&sd->v4l2_dev->lock); + v4l2_dev = sd->v4l2_dev; + + spin_lock(&v4l2_dev->lock); list_del(&sd->list); - spin_unlock(&sd->v4l2_dev->lock); + spin_unlock(&v4l2_dev->lock); sd->v4l2_dev = NULL;
module_put(sd->owner); +#if defined(CONFIG_MEDIA_CONTROLLER) + if (v4l2_dev->mdev) + media_device_unregister_entity(&sd->entity); +#endif video_unregister_device(&sd->devnode); } EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); diff --git a/drivers/media/video/v4l2-subdev.c b/drivers/media/video/v4l2-subdev.c index fbccefd..5e19136 100644 --- a/drivers/media/video/v4l2-subdev.c +++ b/drivers/media/video/v4l2-subdev.c @@ -35,7 +35,10 @@ static int subdev_open(struct file *file) { struct video_device *vdev = video_devdata(file); struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev); - struct v4l2_fh *vfh; +#if defined(CONFIG_MEDIA_CONTROLLER) + struct media_entity *entity; +#endif + struct v4l2_fh *vfh = NULL; int ret;
if (!sd->initialized) @@ -61,11 +64,20 @@ static int subdev_open(struct file *file) v4l2_fh_add(vfh); file->private_data = vfh; } - +#if defined(CONFIG_MEDIA_CONTROLLER) + if (sd->v4l2_dev->mdev) { + entity = media_entity_get(&sd->entity); + if (!entity) { + ret = -EBUSY; + goto err; + } + } +#endif return 0;
err: if (vfh != NULL) { + v4l2_fh_del(vfh); v4l2_fh_exit(vfh); kfree(vfh); } @@ -75,8 +87,16 @@ err:
static int subdev_close(struct file *file) { +#if defined(CONFIG_MEDIA_CONTROLLER) + struct video_device *vdev = video_devdata(file); + struct v4l2_subdev *sd = vdev_to_v4l2_subdev(vdev); +#endif struct v4l2_fh *vfh = file->private_data;
+#if defined(CONFIG_MEDIA_CONTROLLER) + if (sd->v4l2_dev->mdev) + media_entity_put(&sd->entity); +#endif if (vfh != NULL) { v4l2_fh_del(vfh); v4l2_fh_exit(vfh); @@ -176,5 +196,22 @@ void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops) sd->dev_priv = NULL; sd->host_priv = NULL; sd->initialized = 1; +#if defined(CONFIG_MEDIA_CONTROLLER) + sd->entity.name = sd->name; + sd->entity.type = MEDIA_ENTITY_TYPE_V4L2_SUBDEV; +#endif } EXPORT_SYMBOL(v4l2_subdev_init); + +#if defined(CONFIG_MEDIA_CONTROLLER) +int v4l2_subdev_set_power(struct media_entity *entity, int power) +{ + struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity); + + dev_dbg(entity->parent->dev, + "%s power%s\n", entity->name, power ? "on" : "off"); + + return v4l2_subdev_call(sd, core, s_power, power); +} +EXPORT_SYMBOL_GPL(v4l2_subdev_set_power); +#endif diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index 68cbe48..7d55b0c 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -21,6 +21,7 @@ #ifndef _V4L2_SUBDEV_H #define _V4L2_SUBDEV_H
+#include <media/media-entity.h> #include <media/v4l2-common.h> #include <media/v4l2-dev.h> #include <media/v4l2-mediabus.h> @@ -437,6 +438,9 @@ struct v4l2_subdev_ops { stand-alone or embedded in a larger struct. */ struct v4l2_subdev { +#if defined(CONFIG_MEDIA_CONTROLLER) + struct media_entity entity; +#endif struct list_head list; struct module *owner; u32 flags; @@ -458,6 +462,8 @@ struct v4l2_subdev { unsigned int nevents; };
+#define media_entity_to_v4l2_subdev(ent) \ + container_of(ent, struct v4l2_subdev, entity) #define vdev_to_v4l2_subdev(vdev) \ container_of(vdev, struct v4l2_subdev, devnode)
@@ -486,6 +492,10 @@ static inline void *v4l2_get_subdev_hostdata(const struct v4l2_subdev *sd) void v4l2_subdev_init(struct v4l2_subdev *sd, const struct v4l2_subdev_ops *ops);
+#if defined(CONFIG_MEDIA_CONTROLLER) +int v4l2_subdev_set_power(struct media_entity *entity, int power); +#endif + /* Call an ops of a v4l2_subdev, doing the right checks against NULL pointers.