usb: typec: tcpm: Support bist test data mode for compliance

TCPM supports BIST carried mode. PD compliance tests require
BIST Test Data to be supported as well.

Introducing set_bist_data callback to signal tcpc driver for
configuring the port controller hardware to enable/disable
BIST Test Data mode.

Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20200716034128.1251728-1-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/tcpm/tcpm.c

@@ -2748,6 +2748,11 @@ static void tcpm_detach(struct tcpm_port *port)
 	if (!port->attached)
 		return;
 
+	if (port->tcpc->set_bist_data) {
+		tcpm_log(port, "disable BIST MODE TESTDATA");
+		port->tcpc->set_bist_data(port->tcpc, false);
+	}
+
 	if (tcpm_port_is_disconnected(port))
 		port->hard_reset_count = 0;
 
@@ -3557,6 +3562,12 @@ static void run_state_machine(struct tcpm_port *port)
 		case BDO_MODE_CARRIER2:
 			tcpm_pd_transmit(port, TCPC_TX_BIST_MODE_2, NULL);
 			break;
+		case BDO_MODE_TESTDATA:
+			if (port->tcpc->set_bist_data) {
+				tcpm_log(port, "Enable BIST MODE TESTDATA");
+				port->tcpc->set_bist_data(port->tcpc, true);
+			}
+			break;
 		default:
 			break;
 		}

include/linux/usb/tcpm.h

@@ -79,6 +79,7 @@ enum tcpm_transmit_type {
  * @try_role:	Optional; called to set a preferred role
  * @pd_transmit:Called to transmit PD message
  * @mux:	Pointer to multiplexer data
+ * @set_bist_data: Turn on/off bist data mode for compliance testing
  */
 struct tcpc_dev {
 	struct fwnode_handle *fwnode;
@@ -103,6 +104,7 @@ struct tcpc_dev {
 	int (*try_role)(struct tcpc_dev *dev, int role);
 	int (*pd_transmit)(struct tcpc_dev *dev, enum tcpm_transmit_type type,
 			   const struct pd_message *msg);
+	int (*set_bist_data)(struct tcpc_dev *dev, bool on);
 };
 
 struct tcpm_port;