media: cec: add CEC_MSG_FL_RAW flag and msg_is_raw helper function

This adds the userspace API to send raw unchecked CEC messages.
This will require root permissions.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

drivers/media/cec/cec-priv.h

@@ -20,6 +20,11 @@
 /* devnode to cec_adapter */
 #define to_cec_adapter(node) container_of(node, struct cec_adapter, devnode)
 
+static inline bool msg_is_raw(const struct cec_msg *msg)
+{
+	return msg->flags & CEC_MSG_FL_RAW;
+}
+
 /* cec-core.c */
 extern int cec_debug;
 int cec_get_device(struct cec_devnode *devnode);

include/uapi/linux/cec.h

@@ -144,6 +144,7 @@ static inline void cec_msg_set_reply_to(struct cec_msg *msg,
 
 /* cec_msg flags field */
 #define CEC_MSG_FL_REPLY_TO_FOLLOWERS	(1 << 0)
+#define CEC_MSG_FL_RAW			(1 << 1)
 
 /* cec_msg tx/rx_status field */
 #define CEC_TX_STATUS_OK		(1 << 0)