usb: chipidea: handle single role for usb role class

If usb port is configed to be single role, but usb role class
is trying to set unavailable role, don't try to do role change.

Signed-off-by: Jun Li <jun.li@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Link: https://lore.kernel.org/r/20200122014639.22667-2-peter.chen@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/chipidea/ci.h

@@ -302,6 +302,16 @@ static inline enum usb_role ci_role_to_usb_role(struct ci_hdrc *ci)
 		return USB_ROLE_NONE;
 }
 
+static inline enum ci_role usb_role_to_ci_role(enum usb_role role)
+{
+	if (role == USB_ROLE_HOST)
+		return CI_ROLE_HOST;
+	else if (role == USB_ROLE_DEVICE)
+		return CI_ROLE_GADGET;
+	else
+		return CI_ROLE_END;
+}
+
 /**
  * hw_read_id_reg: reads from a identification register
  * @ci: the controller

drivers/usb/chipidea/core.c

@@ -618,9 +618,11 @@ static int ci_usb_role_switch_set(struct device *dev, enum usb_role role)
 	struct ci_hdrc *ci = dev_get_drvdata(dev);
 	struct ci_hdrc_cable *cable = NULL;
 	enum usb_role current_role = ci_role_to_usb_role(ci);
+	enum ci_role ci_role = usb_role_to_ci_role(role);
 	unsigned long flags;
 
-	if (current_role == role)
+	if ((ci_role != CI_ROLE_END && !ci->roles[ci_role]) ||
+	    (current_role == role))
 		return 0;
 
 	pm_runtime_get_sync(ci->dev);