1 files changed, 29 insertions, 0 deletions

diff --git a/include/media/v4l2-fh.h b/include/media/v4l2-fh.h
index 1d72dde320bf..0206aa55be24 100644
--- a/include/media/v4l2-fh.h
+++ b/include/media/v4l2-fh.h
@@ -35,6 +35,7 @@ struct v4l2_fh {
         struct list_head        list;
         struct video_device     *vdev;
         struct v4l2_events      *events; /* events, pending and subscribed */
+        enum v4l2_priority      prio;
 };
 
 /*
@@ -50,8 +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);
 /*
@@ -61,5 +70,25 @@ 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);
+/*
+ * Returns 1 if this filehandle is the only filehandle opened for the
+ * associated video_device. If fh is NULL, then it returns 0.
+ */
+int v4l2_fh_is_singular(struct v4l2_fh *fh);
+/*
+ * Helper function with struct file as argument. If filp->private_data is
+ * NULL, then it will return 0.
+ */
+static inline int v4l2_fh_is_singular_file(struct file *filp)
+{
+        return v4l2_fh_is_singular(filp->private_data);
+}
 
 #endif /* V4L2_EVENT_H */