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xhci: increase usb U3 -> U0 link resume timeout from 100ms to 500ms

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The first U3 wake signal by the host may be lost if the USB 3 connection is
tunneled over USB4, with a runtime suspended USB4 host, and firmware
implemented connection manager.

Specs state the host must wait 100ms (tU3WakeupRetryDelay) before
resending a U3 wake signal if device doesn't respond, leading to U3 -> U0
link transition times around 270ms in the tunneled case.

Fixes: 0200b9f790 ("xhci: Wait until link state trainsits to U0 after setting USB_SS_PORT_LS_U0")
Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20220408134823.2527272-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mathias Nyman 2022-04-08 16:48:23 +03:00 committed by Greg Kroah-Hartman
parent dc92944a01
commit 33597f0c48
1 changed files with 1 additions and 1 deletions
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2
drivers/usb/host/xhci-hub.c
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@ -1434,7 +1434,7 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
}
spin_unlock_irqrestore(&xhci->lock, flags);
if (!wait_for_completion_timeout(&bus_state->u3exit_done[wIndex],
msecs_to_jiffies(100)))
msecs_to_jiffies(500)))
xhci_dbg(xhci, "missing U0 port change event for port %d-%d\n",
hcd->self.busnum, wIndex + 1);
spin_lock_irqsave(&xhci->lock, flags);