]> git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/commit
usb: xhci: Add Clear_TT_Buffer
authorJim Lin <jilin@nvidia.com>
Mon, 3 Jun 2019 10:53:44 +0000 (18:53 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 5 Jun 2019 09:54:38 +0000 (11:54 +0200)
commitef513be0a9057cc6baf5d29566aaaefa214ba344
treefca99456e1b1c5035288bd1cae7b7212b0bf0a90
parent4998f1efd1904dd21697aeeead270e3eb97691dd
usb: xhci: Add Clear_TT_Buffer

USB 2.0 specification chapter 11.17.5 says "as part of endpoint halt
processing for full-/low-speed endpoints connected via a TT, the host
software must use the Clear_TT_Buffer request to the TT to ensure
that the buffer is not in the busy state".

In our case, a full-speed speaker (ConferenceCam) is behind a high-
speed hub (ConferenceCam Connect), sometimes once we get STALL on a
request we may continue to get STALL with the folllowing requests,
like Set_Interface.

Here we invoke usb_hub_clear_tt_buffer() to send Clear_TT_Buffer
request to the hub of the device for the following Set_Interface
requests to the device to get ACK successfully.

Signed-off-by: Jim Lin <jilin@nvidia.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-ring.c
drivers/usb/host/xhci.c
drivers/usb/host/xhci.h