usb: common: add API to get if the platform supports TPL

The TPL (Targeted Peripheral List) is used for targeted hosts
(non-PC hosts), and it can be used at USB OTG & EH certification
and some specific products which need white list.

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/common/usb-common.c

@@ -139,6 +139,21 @@ enum usb_device_speed of_usb_get_maximum_speed(struct device_node *np)
 }
 EXPORT_SYMBOL_GPL(of_usb_get_maximum_speed);
 
+/**
+ * of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
+ * for given targeted hosts (non-PC hosts)
+ * @np: Pointer to the given device_node
+ *
+ * The function gets if the targeted hosts support TPL or not
+ */
+bool of_usb_host_tpl_support(struct device_node *np)
+{
+	if (of_find_property(np, "tpl-support", NULL))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(of_usb_host_tpl_support);
 #endif
 
 MODULE_LICENSE("GPL");

include/linux/usb/of.h

@@ -14,6 +14,7 @@
 #if IS_ENABLED(CONFIG_OF)
 enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np);
 enum usb_device_speed of_usb_get_maximum_speed(struct device_node *np);
+bool of_usb_host_tpl_support(struct device_node *np);
 #else
 static inline enum usb_dr_mode of_usb_get_dr_mode(struct device_node *np)
 {
@@ -25,6 +26,10 @@ of_usb_get_maximum_speed(struct device_node *np)
 {
 	return USB_SPEED_UNKNOWN;
 }
+static inline bool of_usb_host_tpl_support(struct device_node *np)
+{
+	return false;
+}
 #endif
 
 #if IS_ENABLED(CONFIG_OF) && IS_ENABLED(CONFIG_USB_SUPPORT)