usb: xhci: Enable TT to support LS/FS devices behind a HS hub
authorBin Meng <bmeng.cn@gmail.com>
Wed, 19 Jul 2017 13:51:21 +0000 (21:51 +0800)
committerMarek Vasut <marex@denx.de>
Fri, 28 Jul 2017 21:34:37 +0000 (23:34 +0200)
commit78e30987520870e0fc1d6b1cba5b46ce86dfff59
tree882420ab623b3002cef3e2c585f0613b8abb399c
parent196ef8323c53b5d43fd9c244daaca1e2172ca47c
usb: xhci: Enable TT to support LS/FS devices behind a HS hub

So far LS/FS devices directly attached to xHC root port can be
successfully enumerated by xHCI driver, but if they are connected
behind a hub, the enumeration process fails to address the device.

It turns out xHCI driver still misses a part that in the device's
input slot context, all Transaction Translator (TT) related fields
are not programmed. The xHCI spec defines how to enable TT.

Now LS/FS devices like USB keyboard/mouse can be enumerated behind
a high speed hub.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
drivers/usb/host/xhci-mem.c