usb: typec: tcpm: Set USB role switch to device mode when configured as such

Setting the mux to MUX_NONE and the switch to USB_SWITCH_DISCONNECT when
the data-role is device is not correct. Plenty of devices support
operating as USB device through a (separate) USB device controller.

We really need 2 different versions of USB_SWITCH_CONNECT,
USB_SWITCH_CONNECT_HOST and USB_SWITCH_DEVICE. Rather then modifying the
tcpc_usb_switch enum for this, simply remove it and switch to the
usb_role enum which provides exactly this, this will save use needing to
convert betweent the 2 enums when calling an usb-role-switch driver later.

Besides switching to the usb_role type, this commit also actually sets the
mux to TYPEC_MUX_USB and the switch to USB_ROLE_DEVICE instead of setting
both to none when the data-role is device.

This commit also makes tcpm_reset_port() call tcpm_mux_set(port,
TYPEC_MUX_NONE, USB_ROLE_NONE) so that the mux and switch
do _not_ stay in their last mode after a detach.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/typec/tcpm.c

@@ -604,15 +604,15 @@ void tcpm_pd_transmit_complete(struct tcpm_port *port,
 EXPORT_SYMBOL_GPL(tcpm_pd_transmit_complete);
 
 static int tcpm_mux_set(struct tcpm_port *port, enum tcpc_mux_mode mode,
-			enum tcpc_usb_switch config)
+			enum usb_role usb_role)
 {
 	int ret = 0;
 
-	tcpm_log(port, "Requesting mux mode %d, config %d, polarity %d",
-		 mode, config, port->polarity);
+	tcpm_log(port, "Requesting mux mode %d, usb-role %d, polarity %d",
+		 mode, usb_role, port->polarity);
 
 	if (port->tcpc->mux)
-		ret = port->tcpc->mux->set(port->tcpc->mux, mode, config,
+		ret = port->tcpc->mux->set(port->tcpc->mux, mode, usb_role,
 					   port->polarity);
 
 	return ret;
@@ -728,14 +728,15 @@ static int tcpm_set_attached_state(struct tcpm_port *port, bool attached)
 static int tcpm_set_roles(struct tcpm_port *port, bool attached,
 			  enum typec_role role, enum typec_data_role data)
 {
+	enum usb_role usb_role;
 	int ret;
 
 	if (data == TYPEC_HOST)
-		ret = tcpm_mux_set(port, TYPEC_MUX_USB,
-				   TCPC_USB_SWITCH_CONNECT);
+		usb_role = USB_ROLE_HOST;
 	else
-		ret = tcpm_mux_set(port, TYPEC_MUX_NONE,
-				   TCPC_USB_SWITCH_DISCONNECT);
+		usb_role = USB_ROLE_DEVICE;
+
+	ret = tcpm_mux_set(port, TYPEC_MUX_USB, usb_role);
 	if (ret < 0)
 		return ret;
 
@@ -2028,7 +2029,7 @@ out_disable_vconn:
 out_disable_pd:
 	port->tcpc->set_pd_rx(port->tcpc, false);
 out_disable_mux:
-	tcpm_mux_set(port, TYPEC_MUX_NONE, TCPC_USB_SWITCH_DISCONNECT);
+	tcpm_mux_set(port, TYPEC_MUX_NONE, USB_ROLE_NONE);
 	return ret;
 }
 
@@ -2072,6 +2073,7 @@ static void tcpm_reset_port(struct tcpm_port *port)
 	tcpm_init_vconn(port);
 	tcpm_set_current_limit(port, 0, 0);
 	tcpm_set_polarity(port, TYPEC_POLARITY_CC1);
+	tcpm_mux_set(port, TYPEC_MUX_NONE, USB_ROLE_NONE);
 	tcpm_set_attached_state(port, false);
 	port->try_src_count = 0;
 	port->try_snk_count = 0;
@@ -2122,8 +2124,6 @@ static int tcpm_snk_attach(struct tcpm_port *port)
 static void tcpm_snk_detach(struct tcpm_port *port)
 {
 	tcpm_detach(port);
-
-	/* XXX: (Dis)connect SuperSpeed mux? */
 }
 
 static int tcpm_acc_attach(struct tcpm_port *port)

include/linux/usb/tcpm.h

@@ -16,6 +16,7 @@
 #define __LINUX_USB_TCPM_H
 
 #include <linux/bitops.h>
+#include <linux/usb/role.h>
 #include <linux/usb/typec.h>
 #include "pd.h"
 
@@ -98,11 +99,6 @@ struct tcpc_config {
 	const struct typec_altmode_desc *alt_modes;
 };
 
-enum tcpc_usb_switch {
-	TCPC_USB_SWITCH_CONNECT,
-	TCPC_USB_SWITCH_DISCONNECT,
-};
-
 /* Mux state attributes */
 #define TCPC_MUX_USB_ENABLED		BIT(0)	/* USB enabled */
 #define TCPC_MUX_DP_ENABLED		BIT(1)	/* DP enabled */
@@ -119,7 +115,7 @@ enum tcpc_mux_mode {
 
 struct tcpc_mux_dev {
 	int (*set)(struct tcpc_mux_dev *dev, enum tcpc_mux_mode mux_mode,
-		   enum tcpc_usb_switch usb_config,
+		   enum usb_role usb_role,
 		   enum typec_cc_polarity polarity);
 	bool dfp_only;
 	void *priv_data;