Douglas Anderson [off-list ref]
Sent: Friday, May 31, 2024 7:43 AM
[...]
If we happened to get a USB transfer error during the transition to
suspend then the usb_queue_reset_device() that r8152_control_msg()
calls will get dropped on the floor. This is because
usb_lock_device_for_reset() (which usb_queue_reset_device() uses)
silently fails if it's called when a device is suspended or if too
much time passes.
Let's resolve this by resetting the device ourselves in r8152's
resume() function.
NOTE: due to timing, it's _possible_ that we could end up with two USB
resets: the one queued previously and the one called from the resume()
patch. This didn't happen in test cases I ran, though it's conceivably
possible. We can't easily know if this happened since
usb_queue_reset_device() can just silently drop the reset request. In
any case, it's not expected that this is a problem since the two
resets can't run at the same time (because of the device lock) and it
should be OK to reset the device twice. If somehow the double-reset
causes problems we could prevent resets from being queued up while
suspend is running.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Hayes Wang <redacted>
Best Regards,
Hayes