platform/chrome: cros_ec_typec: Tolerate unrecognized mux flags

On occasion, the Chrome Embedded Controller (EC) can send a mux
configuration which doesn't map to a particular data mode. For instance,
dedicated Type C chargers, when connected, may cause only
USB_PD_MUX_POLARITY_INVERTED to be set. This is a valid flag combination
and should not lead to a driver abort.

Modify the mux configuration handling to not return an error when an
unrecognized mux flag combination is encountered. Concordantly, make the
ensuing print a debug level print so as to not pollute the kernel logs.

Cc: Keith Short <keithshort@chromium.org>
Signed-off-by: Prashant Malani <pmalani@chromium.org>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Benson Leung <bleung@chromium.org>
Link: https://lore.kernel.org/r/20201106020305.767202-1-pmalani@chromium.org

drivers/platform/chrome/cros_ec_typec.c

@@ -537,10 +537,9 @@ static int cros_typec_configure_mux(struct cros_typec_data *typec, int port_num,
 		port->state.mode = TYPEC_STATE_USB;
 		ret = typec_mux_set(port->mux, &port->state);
 	} else {
-		dev_info(typec->dev,
-			 "Unsupported mode requested, mux flags: %x\n",
-			 mux_flags);
-		ret = -ENOTSUPP;
+		dev_dbg(typec->dev,
+			"Unrecognized mode requested, mux flags: %x\n",
+			mux_flags);
 	}
 
 	return ret;