[media] cec: add cec_s_phys_addr_from_edid helper function

This function simplifies the integration of CEC in DRM drivers.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

Documentation/media/kapi/cec-core.rst

@@ -306,6 +306,14 @@ then the CEC adapter will be disabled. If you change a valid physical address
 to another valid physical address, then this function will first set the
 address to CEC_PHYS_ADDR_INVALID before enabling the new physical address.
 
+.. c:function::
+	void cec_s_phys_addr_from_edid(struct cec_adapter *adap,
+				       const struct edid *edid);
+
+A helper function that extracts the physical address from the edid struct
+and calls cec_s_phys_addr() with that address, or CEC_PHYS_ADDR_INVALID
+if the EDID did not contain a physical address or edid was a NULL pointer.
+
 .. c:function::
 	int cec_s_log_addrs(struct cec_adapter *adap,
 			    struct cec_log_addrs *log_addrs, bool block);