[RFC PATCH] usb: xhci: skip re-check pending port event if hibernated

Chunfeng Yun chunfeng.yun at mediatek.com
Mon Oct 25 04:42:09 PDT 2021


When xHCI controller hibernated, the root hub lost power, if controller
support Port Power Control (PPC), PP is not set at xhci_resume() and
set by hub_reset_resume() later, so no need check pending port event.
If PPC is not supported, device is disconneced, seems do not send out
U3 LFPS wake signal, no need re-check again and drop 120ms delay to
save resume time.

Reported-by: Yun-Chien Yu <yun-chien.yu at mediatek.com>
Signed-off-by: Chunfeng Yun <chunfeng.yun at mediatek.com>
---
 drivers/usb/host/xhci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index f3dabd02382c..a7a2bf5bc208 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1235,7 +1235,7 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 		 * the first wake signalling failed, give it that chance.
 		 */
 		pending_portevent = xhci_pending_portevent(xhci);
-		if (!pending_portevent) {
+		if (!pending_portevent && !hibernated) {
 			msleep(120);
 			pending_portevent = xhci_pending_portevent(xhci);
 		}
-- 
2.18.0




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