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

Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Praveena Nadahally <praveen.nadahally@stericsson.com>
Signed-off-by: Parirajan Muthalagu <parirajan.muthalagu@stericsson.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Parirajan Muthalagu 15 years ago
parent
commit
37b5801e16
2 changed files with 17 additions and 1 deletions
  1. 7 1
      drivers/usb/gadget/composite.c
  2. 10 0
      include/linux/usb/ch9.h

+ 7 - 1
drivers/usb/gadget/composite.c

@@ -1074,7 +1074,13 @@ static int composite_bind(struct usb_gadget *gadget)
 	cdev->bufsiz = USB_BUFSIZ;
 	cdev->driver = composite;
 
-	usb_gadget_set_selfpowered(gadget);
+	/*
+	 * 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.
 	 * we force endpoints to start unassigned; few controller

+ 10 - 0
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 */