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.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 0200b9f790b0 ("xhci: Wait until link state trainsits to U0 after setting USB_SS_PORT_LS_U0")
Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
---
drivers/usb/host/xhci-hub.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 1e7dc130c39a..f65f1ba2b592 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -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);
--
2.25.1
