[media] cec: add CEC_LOG_ADDRS_FL_ALLOW_UNREG_FALLBACK flag

Currently if none of the requested logical addresses can be claimed, the
framework will fall back to the Unregistered logical address.

Add a flag to enable this explicitly. By default it will just go back to
the unconfigured state.

Usually Unregistered is not something you want since the functionality is
very limited. Unless the application has support for this, it will fail
to work correctly. So require that the application explicitly requests
this.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
diff --git a/include/linux/cec.h b/include/linux/cec.h
index b3e2289..851968e 100644
--- a/include/linux/cec.h
+++ b/include/linux/cec.h
@@ -364,7 +364,7 @@
  * @num_log_addrs: how many logical addresses should be claimed. Set by the
  *	caller.
  * @vendor_id: the vendor ID of the device. Set by the caller.
- * @flags: set to 0.
+ * @flags: flags.
  * @osd_name: the OSD name of the device. Set by the caller.
  * @primary_device_type: the primary device type for each logical address.
  *	Set by the caller.
@@ -389,6 +389,9 @@
 	__u8 features[CEC_MAX_LOG_ADDRS][12];
 };
 
+/* Allow a fallback to unregistered */
+#define CEC_LOG_ADDRS_FL_ALLOW_UNREG_FALLBACK	(1 << 0)
+
 /* Events */
 
 /* Event that occurs when the adapter state changes */