diff options
| author | Hans Verkuil <hverkuil@xs4all.nl> | 2011-01-08 09:36:04 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@redhat.com> | 2011-03-22 16:37:57 -0300 |
| commit | 73cb42068cff419e72456940c713ceb5efa68c2a (patch) | |
| tree | 2e2cfa9f87b584774a7dc496ec6b46431bd7ce56 | |
| parent | fc5602be7ca5b55174c5d6595089718779b28dfa (diff) | |
[media] v4l2-fh: add v4l2_fh_open and v4l2_fh_release helper functions
Add two new functions: v4l2_fh_open allocates and initializes a struct v4l2_fh
based on a struct file pointer and v4l2_fh_release releases and frees a struct
v4l2_fh.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
| -rw-r--r-- | drivers/media/video/v4l2-fh.c | 28 | ||||
| -rw-r--r-- | include/media/v4l2-fh.h | 15 |
2 files changed, 43 insertions, 0 deletions
diff --git a/drivers/media/video/v4l2-fh.c b/drivers/media/video/v4l2-fh.c index 78a1608a09d..27242e5ca43 100644 --- a/drivers/media/video/v4l2-fh.c +++ b/drivers/media/video/v4l2-fh.c @@ -23,6 +23,7 @@ */ #include <linux/bitops.h> +#include <linux/slab.h> #include <media/v4l2-dev.h> #include <media/v4l2-fh.h> #include <media/v4l2-event.h> @@ -60,6 +61,20 @@ void v4l2_fh_add(struct v4l2_fh *fh) } EXPORT_SYMBOL_GPL(v4l2_fh_add); +int v4l2_fh_open(struct file *filp) +{ + struct video_device *vdev = video_devdata(filp); + struct v4l2_fh *fh = kzalloc(sizeof(*fh), GFP_KERNEL); + + filp->private_data = fh; + if (fh == NULL) + return -ENOMEM; + v4l2_fh_init(fh, vdev); + v4l2_fh_add(fh); + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_fh_open); + void v4l2_fh_del(struct v4l2_fh *fh) { unsigned long flags; @@ -81,3 +96,16 @@ void v4l2_fh_exit(struct v4l2_fh *fh) v4l2_event_free(fh); } EXPORT_SYMBOL_GPL(v4l2_fh_exit); + +int v4l2_fh_release(struct file *filp) +{ + struct v4l2_fh *fh = filp->private_data; + + if (fh) { + v4l2_fh_del(fh); + v4l2_fh_exit(fh); + kfree(fh); + } + return 0; +} +EXPORT_SYMBOL_GPL(v4l2_fh_release); diff --git a/include/media/v4l2-fh.h b/include/media/v4l2-fh.h index 5fc5ba96e1d..5657881cd44 100644 --- a/include/media/v4l2-fh.h +++ b/include/media/v4l2-fh.h @@ -51,8 +51,16 @@ int v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev); */ void v4l2_fh_add(struct v4l2_fh *fh); /* + * Can be used as the open() op of v4l2_file_operations. + * It allocates a v4l2_fh and inits and adds it to the video_device associated + * with the file pointer. + */ +int v4l2_fh_open(struct file *filp); +/* * Remove file handle from the list of file handles. Must be called in * v4l2_file_operations->release() handler if the driver uses v4l2_fh. + * On error filp->private_data will be NULL, otherwise it will point to + * the v4l2_fh struct. */ void v4l2_fh_del(struct v4l2_fh *fh); /* @@ -62,5 +70,12 @@ void v4l2_fh_del(struct v4l2_fh *fh); * driver uses v4l2_fh. */ void v4l2_fh_exit(struct v4l2_fh *fh); +/* + * Can be used as the release() op of v4l2_file_operations. + * It deletes and exits the v4l2_fh associated with the file pointer and + * frees it. It will do nothing if filp->private_data (the pointer to the + * v4l2_fh struct) is NULL. This function always returns 0. + */ +int v4l2_fh_release(struct file *filp); #endif /* V4L2_EVENT_H */ |