Browse Source

usb: Read device descriptor after device is addressed for xHCI

For xHCI it is not possible to read a device descriptor before it
has been assigned an address. That's why usb_setup_descriptor()
was called with 'do_read' being false. But we really need try to
read the device descriptor before starting any real communication
with the default control endpoint.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Bin Meng 7 năm trước cách đây
mục cha
commit
932bb668bb
1 tập tin đã thay đổi với 11 bổ sung0 xóa
  1. 11 0
      common/usb.c

+ 11 - 0
common/usb.c

@@ -1052,6 +1052,17 @@ static int usb_prepare_device(struct usb_device *dev, int addr, bool do_read,
 
 	mdelay(10);	/* Let the SET_ADDRESS settle */
 
+	/*
+	 * If we haven't read device descriptor before, read it here
+	 * after device is assigned an address. This is only applicable
+	 * to xHCI so far.
+	 */
+	if (!do_read) {
+		err = usb_setup_descriptor(dev, true);
+		if (err)
+			return err;
+	}
+
 	return 0;
 }