usb: roles: Leave the private driver data pointer to the drivers

Adding usb_role_switch_get/set_drvdata() functions that the
switch drivers can use for setting and getting private data
pointer that is associated with the switch.

Signed-off-by: Heikki Krogerus <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/roles/class.c

···
 	sw->dev.fwnode = desc->fwnode;
 	sw->dev.class = role_class;
 	sw->dev.type = &usb_role_dev_type;
+	dev_set_drvdata(&sw->dev, desc->driver_data);
 	dev_set_name(&sw->dev, "%s-role-switch", dev_name(parent));
 
 	ret = device_register(&sw->dev);
···
 		device_unregister(&sw->dev);
 }
 EXPORT_SYMBOL_GPL(usb_role_switch_unregister);
+
+/**
+ * usb_role_switch_set_drvdata - Assign private data pointer to a switch
+ * @sw: USB Role Switch
+ * @data: Private data pointer
+ */
+void usb_role_switch_set_drvdata(struct usb_role_switch *sw, void *data)
+{
+	dev_set_drvdata(&sw->dev, data);
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_set_drvdata);
+
+/**
+ * usb_role_switch_get_drvdata - Get the private data pointer of a switch
+ * @sw: USB Role Switch
+ */
+void *usb_role_switch_get_drvdata(struct usb_role_switch *sw)
+{
+	return dev_get_drvdata(&sw->dev);
+}
+EXPORT_SYMBOL_GPL(usb_role_switch_get_drvdata);
 
 static int __init usb_roles_init(void)
 {

include/linux/usb/role.h

···
  * @set: Callback for setting the role
  * @get: Callback for getting the role (optional)
  * @allow_userspace_control: If true userspace may change the role through sysfs
+ * @driver_data: Private data pointer
  *
  * @usb2_port and @usb3_port will point to the USB host port and @udc to the USB
  * device controller behind the USB connector with the role switch. If
···
 	usb_role_switch_set_t set;
 	usb_role_switch_get_t get;
 	bool allow_userspace_control;
+	void *driver_data;
 };
 
 
···
 usb_role_switch_register(struct device *parent,
 			 const struct usb_role_switch_desc *desc);
 void usb_role_switch_unregister(struct usb_role_switch *sw);
+
+void usb_role_switch_set_drvdata(struct usb_role_switch *sw, void *data);
+void *usb_role_switch_get_drvdata(struct usb_role_switch *sw);
 #else
 static inline int usb_role_switch_set_role(struct usb_role_switch *sw,
 		enum usb_role role)
···
 }
 
 static inline void usb_role_switch_unregister(struct usb_role_switch *sw) { }
+
+static inline void
+usb_role_switch_set_drvdata(struct usb_role_switch *sw, void *data)
+{
+}
+
+static inline void *usb_role_switch_get_drvdata(struct usb_role_switch *sw)
+{
+	return NULL;
+}
+
 #endif
 
 #endif /* __LINUX_USB_ROLE_H */