[media] v4l2_prio: move from v4l2-common to v4l2-dev
We are going to move priority handling into the v4l2 core. As a consequence
the v4l2_prio helper functions need to be moved into the core videodev
module as well to prevent circular dependencies.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/v4l2-dev.c b/drivers/media/video/v4l2-dev.c
index e405b80..65d546f 100644
--- a/drivers/media/video/v4l2-dev.c
+++ b/drivers/media/video/v4l2-dev.c
@@ -182,6 +182,70 @@
}
EXPORT_SYMBOL(video_devdata);
+
+/* Priority handling */
+
+static inline bool prio_is_valid(enum v4l2_priority prio)
+{
+ return prio == V4L2_PRIORITY_BACKGROUND ||
+ prio == V4L2_PRIORITY_INTERACTIVE ||
+ prio == V4L2_PRIORITY_RECORD;
+}
+
+void v4l2_prio_init(struct v4l2_prio_state *global)
+{
+ memset(global, 0, sizeof(*global));
+}
+EXPORT_SYMBOL(v4l2_prio_init);
+
+int v4l2_prio_change(struct v4l2_prio_state *global, enum v4l2_priority *local,
+ enum v4l2_priority new)
+{
+ if (!prio_is_valid(new))
+ return -EINVAL;
+ if (*local == new)
+ return 0;
+
+ atomic_inc(&global->prios[new]);
+ if (prio_is_valid(*local))
+ atomic_dec(&global->prios[*local]);
+ *local = new;
+ return 0;
+}
+EXPORT_SYMBOL(v4l2_prio_change);
+
+void v4l2_prio_open(struct v4l2_prio_state *global, enum v4l2_priority *local)
+{
+ v4l2_prio_change(global, local, V4L2_PRIORITY_DEFAULT);
+}
+EXPORT_SYMBOL(v4l2_prio_open);
+
+void v4l2_prio_close(struct v4l2_prio_state *global, enum v4l2_priority local)
+{
+ if (prio_is_valid(local))
+ atomic_dec(&global->prios[local]);
+}
+EXPORT_SYMBOL(v4l2_prio_close);
+
+enum v4l2_priority v4l2_prio_max(struct v4l2_prio_state *global)
+{
+ if (atomic_read(&global->prios[V4L2_PRIORITY_RECORD]) > 0)
+ return V4L2_PRIORITY_RECORD;
+ if (atomic_read(&global->prios[V4L2_PRIORITY_INTERACTIVE]) > 0)
+ return V4L2_PRIORITY_INTERACTIVE;
+ if (atomic_read(&global->prios[V4L2_PRIORITY_BACKGROUND]) > 0)
+ return V4L2_PRIORITY_BACKGROUND;
+ return V4L2_PRIORITY_UNSET;
+}
+EXPORT_SYMBOL(v4l2_prio_max);
+
+int v4l2_prio_check(struct v4l2_prio_state *global, enum v4l2_priority local)
+{
+ return (local < v4l2_prio_max(global)) ? -EBUSY : 0;
+}
+EXPORT_SYMBOL(v4l2_prio_check);
+
+
static ssize_t v4l2_read(struct file *filp, char __user *buf,
size_t sz, loff_t *off)
{