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usb: Assure Get Descriptor request is in separate microframe 

The Kingston DT Ultimate USB 3.0 stick is sensitive to this first
Get Descriptor request and if the request is not in a separate
microframe, the stick refuses to operate. Add slight delay, which
is enough for one microframe to pass on any USB spec revision.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chin Liang See <clsee@altera.com>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Stephen Warren <swarren@nvidia.com>
This commit is contained in:
Marek Vasut 2016-04-27 03:32:56 +02:00
parent f647bf0ba3
commit ef71290be9
1 changed files with 8 additions and 0 deletions
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8
common/usb.c
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@ -1077,6 +1077,14 @@ int usb_select_config(struct usb_device *dev)
le16_to_cpus(&dev->descriptor.idProduct);
le16_to_cpus(&dev->descriptor.bcdDevice);
/*
* Kingston DT Ultimate 32GB USB 3.0 seems to be extremely sensitive
* about this first Get Descriptor request. If there are any other
* requests in the first microframe, the stick crashes. Wait about
* one microframe duration here (1mS for USB 1.x , 125uS for USB 2.0).
*/
mdelay(1);
/* only support for one config for now */
err = usb_get_configuration_len(dev, 0);
if (err >= 0) {