[RFC v4 01/17] [media] v4l: create v4l2_event_subscribe_v4l2()

[Gustavo Padovan <gustavo@padovan.org>]

From: Gustavo Padovan <gustavo.padovan@collabora.com>

We need a common function to subscribe all the common events in drivers,
so far we had only V4L2_EVENT_CTRL, so such a function wasn't necessary,
but we are about to introduce a new event for the upcoming explicit fences
implementation, thus a common place is needed.

Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.com>
---
 drivers/media/v4l2-core/v4l2-event.c | 12 ++++++++++++
 include/media/v4l2-event.h           |  8 ++++++++
 2 files changed, 20 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-event.c b/drivers/media/v4l2-core/v4l2-event.c
index 968c2eb08b5a..313ee9d1f9ee 100644
--- a/drivers/media/v4l2-core/v4l2-event.c
+++ b/drivers/media/v4l2-core/v4l2-event.c
@@ -20,6 +20,7 @@
 #include <media/v4l2-dev.h>
 #include <media/v4l2-fh.h>
 #include <media/v4l2-event.h>
+#include <media/v4l2-ctrls.h>
 
 #include <linux/mm.h>
 #include <linux/sched.h>
@@ -354,3 +355,14 @@ int v4l2_src_change_event_subdev_subscribe(struct v4l2_subdev *sd,
 	return v4l2_src_change_event_subscribe(fh, sub);
 }
 EXPORT_SYMBOL_GPL(v4l2_src_change_event_subdev_subscribe);
+
+int v4l2_subscribe_event_v4l2(struct v4l2_fh *fh,
+			      const struct v4l2_event_subscription *sub)
+{
+	switch (sub->type) {
+	case V4L2_EVENT_CTRL:
+		return v4l2_ctrl_subscribe_event(fh, sub);
+	}
+	return -EINVAL;
+}
+EXPORT_SYMBOL(v4l2_subscribe_event_v4l2);
diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h
index 6741910c3a18..2b794f2ad824 100644
--- a/include/media/v4l2-event.h
+++ b/include/media/v4l2-event.h
@@ -236,4 +236,12 @@ int v4l2_src_change_event_subscribe(struct v4l2_fh *fh,
 int v4l2_src_change_event_subdev_subscribe(struct v4l2_subdev *sd,
 					   struct v4l2_fh *fh,
 					   struct v4l2_event_subscription *sub);
+/**
+ * v4l2_subscribe_event_v4l2 - helper function that subscribe all v4l2 events
+ *
+ * @fh: pointer to struct v4l2_fh
+ * @sub: pointer to &struct v4l2_event_subscription
+ */
+int v4l2_subscribe_event_v4l2(struct v4l2_fh *fh,
+			      const struct v4l2_event_subscription *sub);
 #endif /* V4L2_EVENT_H */
-- 
2.13.6