[SRU] [B/C/D/Unstable/OEM-B/OEM-OSP1-B] [PATCH 0/1] Fix disappearing Qualcomm WiFi/Bluetooth

[Kai-Heng Feng]

BugLink: https://bugs.launchpad.net/bugs/1757218

[Impact]
Qualcomm WiFi/Bluetooth may disappear after boot.

[Fix]
Disable USB2 LPM at shutdown phase, to prevent it from lingering in LPM
L1. Pull back the device to full power before shutdown imitates the
behavior on Windows.

[Test]
The affected user confimed it fixes the issue.
I can also confirm that
a) The power drain in S5 is much lower,
b) Both WiFi and Bluetooth are always present during reboot stress test.

[Regression Potential]
Low. Only a limited number of USB2 devices that support LPM.

Kai-Heng Feng (1):
  UBUNTU: SAUCE: USB: Disable USB2 LPM at shutdown

 drivers/usb/core/port.c | 9 +++++++++
 1 file changed, 9 insertions(+)

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2.17.1