staging: typec: tcpci: Only touch target bit when enable vconn

We need regmap_update_bits to avoid touch any other bits when
enable or disable vconn.

Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/typec/tcpci.c

@@ -218,12 +218,9 @@ static int tcpci_set_vconn(struct tcpc_dev *tcpc, bool enable)
 			return ret;
 	}
 
-	ret = regmap_write(tcpci->regmap, TCPC_POWER_CTRL,
-			   enable ? TCPC_POWER_CTRL_VCONN_ENABLE : 0);
-	if (ret < 0)
-		return ret;
-
-	return 0;
+	return regmap_update_bits(tcpci->regmap, TCPC_POWER_CTRL,
+				TCPC_POWER_CTRL_VCONN_ENABLE,
+				enable ? TCPC_POWER_CTRL_VCONN_ENABLE : 0);
 }
 
 static int tcpci_set_roles(struct tcpc_dev *tcpc, bool attached,