platform/chrome: cros_ec_typec: Register port partner

Register (and unregister) the port partner when a connect (and
disconnect) is detected.

Co-developed-by: Jon Flatley <[email protected]>
Signed-off-by: Prashant Malani <[email protected]>
Reviewed-by: Heikki Krogerus <[email protected]>
Signed-off-by: Enric Balletbo i Serra <[email protected]>

Author: Prashant Malani

drivers/platform/chrome/cros_ec_typec.c

@@ -22,6 +22,9 @@ struct cros_typec_port {
 	struct typec_port *port;
 	/* Initial capabilities for the port. */
 	struct typec_capability caps;
+	struct typec_partner *partner;
+	/* Port partner PD identity info. */
+	struct usb_pd_identity p_identity;
 };
 
 /* Platform-specific data for the Chrome OS EC Type C controller. */
@@ -190,6 +193,30 @@ static int cros_typec_ec_command(struct cros_typec_data *typec,
 	return ret;
 }
 
+static int cros_typec_add_partner(struct cros_typec_data *typec, int port_num,
+				  bool pd_en)
+{
+	struct cros_typec_port *port = typec->ports[port_num];
+	struct typec_partner_desc p_desc = {
+		.usb_pd = pd_en,
+	};
+	int ret = 0;
+
+	/*
+	 * Fill an initial PD identity, which will then be updated with info
+	 * from the EC.
+	 */
+	p_desc.identity = &port->p_identity;
+
+	port->partner = typec_register_partner(port->port, &p_desc);
+	if (IS_ERR(port->partner)) {
+		ret = PTR_ERR(port->partner);
+		port->partner = NULL;
+	}
+
+	return ret;
+}
+
 static void cros_typec_set_port_params_v0(struct cros_typec_data *typec,
 		int port_num, struct ec_response_usb_pd_control *resp)
 {
@@ -212,6 +239,8 @@ static void cros_typec_set_port_params_v1(struct cros_typec_data *typec,
 {
 	struct typec_port *port = typec->ports[port_num]->port;
 	enum typec_orientation polarity;
+	bool pd_en;
+	int ret;
 
 	if (!(resp->enabled & PD_CTRL_RESP_ENABLED_CONNECTED))
 		polarity = TYPEC_ORIENTATION_NONE;
@@ -226,6 +255,25 @@ static void cros_typec_set_port_params_v1(struct cros_typec_data *typec,
 			TYPEC_SOURCE : TYPEC_SINK);
 	typec_set_vconn_role(port, resp->role & PD_CTRL_RESP_ROLE_VCONN ?
 			TYPEC_SOURCE : TYPEC_SINK);
+
+	/* Register/remove partners when a connect/disconnect occurs. */
+	if (resp->enabled & PD_CTRL_RESP_ENABLED_CONNECTED) {
+		if (typec->ports[port_num]->partner)
+			return;
+
+		pd_en = resp->enabled & PD_CTRL_RESP_ENABLED_PD_CAPABLE;
+		ret = cros_typec_add_partner(typec, port_num, pd_en);
+		if (!ret)
+			dev_warn(typec->dev,
+				 "Failed to register partner on port: %d\n",
+				 port_num);
+	} else {
+		if (!typec->ports[port_num]->partner)
+			return;
+
+		typec_unregister_partner(typec->ports[port_num]->partner);
+		typec->ports[port_num]->partner = NULL;
+	}
 }
 
 static int cros_typec_port_update(struct cros_typec_data *typec, int port_num)