diff options
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-device.c | 19 | ||||
| -rw-r--r-- | include/media/v4l2-subdev.h | 13 |
2 files changed, 26 insertions, 6 deletions
diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c index e0ddb9a52bd1..7cca0de1b730 100644 --- a/drivers/media/v4l2-core/v4l2-device.c +++ b/drivers/media/v4l2-core/v4l2-device.c @@ -216,10 +216,18 @@ error_module: } EXPORT_SYMBOL_GPL(v4l2_device_register_subdev); +static void v4l2_subdev_release(struct v4l2_subdev *sd) +{ + struct module *owner = !sd->owner_v4l2_dev ? sd->owner : NULL; + + if (sd->internal_ops && sd->internal_ops->release) + sd->internal_ops->release(sd); + module_put(owner); +} + static void v4l2_device_release_subdev_node(struct video_device *vdev) { - struct v4l2_subdev *sd = video_get_drvdata(vdev); - sd->devnode = NULL; + v4l2_subdev_release(video_get_drvdata(vdev)); kfree(vdev); } @@ -318,8 +326,9 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) media_device_unregister_entity(&sd->entity); } #endif - video_unregister_device(sd->devnode); - if (!sd->owner_v4l2_dev) - module_put(sd->owner); + if (sd->devnode) + video_unregister_device(sd->devnode); + else + v4l2_subdev_release(sd); } EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); diff --git a/include/media/v4l2-subdev.h b/include/media/v4l2-subdev.h index 349e1c18cf48..e807aa96ed3b 100644 --- a/include/media/v4l2-subdev.h +++ b/include/media/v4l2-subdev.h @@ -755,7 +755,17 @@ struct v4l2_subdev_ops { * * @open: called when the subdev device node is opened by an application. * - * @close: called when the subdev device node is closed. + * @close: called when the subdev device node is closed. Please note that + * it is possible for @close to be called after @unregistered! + * + * @release: called when the last user of the subdev device is gone. This + * happens after the @unregistered callback and when the last open + * filehandle to the v4l-subdevX device node was closed. If no device + * node was created for this sub-device, then the @release callback + * is called right after the @unregistered callback. + * The @release callback is typically used to free the memory containing + * the v4l2_subdev structure. It is almost certainly required for any + * sub-device that sets the V4L2_SUBDEV_FL_HAS_DEVNODE flag. * * .. note:: * Never call this from drivers, only the v4l2 framework can call @@ -766,6 +776,7 @@ struct v4l2_subdev_internal_ops { void (*unregistered)(struct v4l2_subdev *sd); int (*open)(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh); int (*close)(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh); + void (*release)(struct v4l2_subdev *sd); }; #define V4L2_SUBDEV_NAME_SIZE 32 |