]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
usb: Handle USB3 remote wakeup for LPM enabled devices correctly
authorLee, Chiasheng <chiasheng.lee@intel.com>
Thu, 20 Jun 2019 07:56:04 +0000 (10:56 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 26 Jul 2019 07:13:07 +0000 (09:13 +0200)
commit24d22d774481e7d586534937b0f24d0a0dfb7e40
tree704899b7896c07e0744e13a760e8356501e36041
parent584cd9936ac1c52517711dbc0d6f380177069c97
usb: Handle USB3 remote wakeup for LPM enabled devices correctly

commit e244c4699f859cf7149b0781b1894c7996a8a1df upstream.

With Link Power Management (LPM) enabled USB3 links transition to low
power U1/U2 link states from U0 state automatically.

Current hub code detects USB3 remote wakeups by checking if the software
state still shows suspended, but the link has transitioned from suspended
U3 to enabled U0 state.

As it takes some time before the hub thread reads the port link state
after a USB3 wake notification, the link may have transitioned from U0
to U1/U2, and wake is not detected by hub code.

Fix this by handling U1/U2 states in the same way as U0 in USB3 wakeup
handling

This patch should be added to stable kernels since 4.13 where LPM was
kept enabled during suspend/resume

Cc: <stable@vger.kernel.org> # v4.13+
Signed-off-by: Lee, Chiasheng <chiasheng.lee@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/core/hub.c