USB Gadget: Verify VBUS current before setting the device self-powered bit

Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NPraveena Nadahally <praveen.nadahally@stericsson.com>
Signed-off-by: NParirajan Muthalagu <parirajan.muthalagu@stericsson.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/composite.c

@@ -1074,6 +1074,12 @@ static int composite_bind(struct usb_gadget *gadget)
 	cdev->bufsiz = USB_BUFSIZ;
 	cdev->driver = composite;
 
+	/*
+	 * As per USB compliance update, a device that is actively drawing
+	 * more than 100mA from USB must report itself as bus-powered in
+	 * the GetStatus(DEVICE) call.
+	 */
+	if (CONFIG_USB_GADGET_VBUS_DRAW <= USB_SELF_POWER_VBUS_MAX_DRAW)
 		usb_gadget_set_selfpowered(gadget);
 
 	/* interface and string IDs start at zero via kzalloc.

include/linux/usb/ch9.h

@@ -808,4 +808,14 @@ enum usb_device_state {
 	 */
 };
 
+/*-------------------------------------------------------------------------*/
+
+/*
+ * As per USB compliance update, a device that is actively drawing
+ * more than 100mA from USB must report itself as bus-powered in
+ * the GetStatus(DEVICE) call.
+ * http://compliance.usb.org/index.asp?UpdateFile=Electrical&Format=Standard#34
+ */
+#define USB_SELF_POWER_VBUS_MAX_DRAW		100
+
 #endif /* __LINUX_USB_CH9_H */