media: cec: rework the cec event handling

Event handling was always fairly simplistic since there were only
two events. With the addition of pin events this needed to be redesigned.

The state_change and lost_msgs events are now core events with the
guarantee that the last state is always available. The new pin events
are a queue of events (up to 64 for each event) and the oldest event
will be dropped if the application cannot keep up. Lost events are
marked with a new event flag.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/uapi/linux/cec.h b/include/uapi/linux/cec.h
index bba73f33c8aa..d87a67b0bb06 100644
--- a/include/uapi/linux/cec.h
+++ b/include/uapi/linux/cec.h
@@ -412,6 +412,7 @@ struct cec_log_addrs {
 #define CEC_EVENT_PIN_HIGH		4
 
 #define CEC_EVENT_FL_INITIAL_STATE	(1 << 0)
+#define CEC_EVENT_FL_DROPPED_EVENTS	(1 << 1)
 
 /**
  * struct cec_event_state_change - used when the CEC adapter changes state.
@@ -424,7 +425,7 @@ struct cec_event_state_change {
 };
 
 /**
- * struct cec_event_lost_msgs - tells you how many messages were lost due.
+ * struct cec_event_lost_msgs - tells you how many messages were lost.
  * @lost_msgs: how many messages were lost.
  */
 struct cec_event_lost_msgs {