xhci: Calculate old endpoints correctly on device reset
authorBrian Campbell <bacam@z273.org.uk>
Tue, 21 Jul 2015 14:20:28 +0000 (17:20 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 22 Jul 2015 21:19:36 +0000 (14:19 -0700)
commit326124a027abc9a7f43f72dc94f6f0f7a55b02b3
tree3369e0da02e0724eab5c420ab01719887f4a5d90
parent3496810663922617d4b706ef2780c279252ddd6a
xhci: Calculate old endpoints correctly on device reset

When resetting a device the number of active TTs may need to be
corrected by xhci_update_tt_active_eps, but the number of old active
endpoints supplied to it was always zero, so the number of TTs and the
bandwidth reserved for them was not updated, and could rise
unnecessarily.

This affected systems using Intel's Patherpoint chipset, which rely on
software bandwidth checking.  For example, a Lenovo X230 would lose the
ability to use ports on the docking station after enough suspend/resume
cycles because the bandwidth calculated would rise with every cycle when
a suitable device is attached.

The correct number of active endpoints is calculated in the same way as
in xhci_reserve_bandwidth.

Cc: <stable@vger.kernel.org>
Signed-off-by: Brian Campbell <bacam@z273.org.uk>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci.c