[SRU] [E/F/Unstable/OEM-OSP1-B] [PATCH 0/4] Make Dell WD19 dock more reliable after suspend

[Kai-Heng Feng]

BugLink: https://bugs.launchpad.net/bugs/1868217

[Impact]
When Dell WD19 dock connects multiple USB3 storage devices, the USB Hub
used internally may stop working after suspend.

[Fix]
Disable LPM on the Realtek USB Hub, and let xHCI controller make sure
the link state transition is completed.

[Test]
After applying the patches, the Dell WD19 works reliably after thousand
times for suspend/resume cycle.

[Regression Potential]
Low. This replaces the currently "msleep" way with more robust
mechanism. I also test other systems and nothing breaks.

Kai-Heng Feng (3):
  xhci: Ensure link state is U3 after setting USB_SS_PORT_LS_U3
  xhci: Wait until link state trainsits to U0 after setting
    USB_SS_PORT_LS_U0
  USB: Disable LPM on WD19's Realtek Hub

Mathias Nyman (1):
  xhci: Finetune host initiated USB3 rootport link suspend and resume

 drivers/usb/core/quirks.c    |  3 ++
 drivers/usb/host/xhci-hub.c  | 61 ++++++++++++++++++++++++++++++------
 drivers/usb/host/xhci-mem.c  |  1 +
 drivers/usb/host/xhci-ring.c |  1 +
 drivers/usb/host/xhci.h      |  1 +
 5 files changed, 57 insertions(+), 10 deletions(-)

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2.17.1