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 ---
common/usb.c | 11 +++++++++++ 1 file changed, 11 insertions(+)
diff --git a/common/usb.c b/common/usb.c index 2aaf932..e469534 100644 --- a/common/usb.c +++ b/common/usb.c @@ -1051,6 +1051,17 @@ 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; }