[SRU][P][PATCH 0/3] Add waiting latency for USB port resume

[En-Wei Wu]

BugLink: https://bugs.launchpad.net/bugs/2115478

[ Impact ]

On certain USB3 device topologies, the hub will enter runtime resume
before the down stream device to wake up. When a device is connect to
such hub, the hub will enter runtime resume before the device generates
any activities, making it not able to get detected.

[ Fix ]

Cherry-pick the following commit:

1. usb: hub: fix detection of high tier USB3 devices behind suspended hubs [1]

and backport the subsequent two commits, which fix an unexpected issue caused
by the commit above:

2. usb: hub: Fix flushing and scheduling of delayed work that tunes runtime pm
3. usb: hub: Fix flushing of delayed work used for post resume purposes

[ Test ]

1. Connect SD25TB5/WD25TB5 dock to SUT.
2. Connect USB3.0/3.1 sotarge to dock's USB port.
3. The USB storage should be recognized.

[ Where problems could occurs ]

This may increase resume latency for deeper USB device
hierarchy.

[ Additional Information ]

[1]
https://lore.kernel.org/linux-usb/20250611112441.2267883-1-mathias.nyman@linux.intel.com/

Mathias Nyman (3):
  usb: hub: fix detection of high tier USB3 devices behind suspended
    hubs
  usb: hub: Fix flushing and scheduling of delayed work that tunes
    runtime pm
  usb: hub: Fix flushing of delayed work used for post resume purposes

 drivers/usb/core/hub.c | 28 ++++++++++++++++++++++++++++
 drivers/usb/core/hub.h |  1 +
 2 files changed, 29 insertions(+)

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2.43.0