xhci: Improve the XHCI system resume time
authorBasavaraj Natikar <Basavaraj.Natikar@amd.com>
Fri, 28 Apr 2023 14:00:56 +0000 (19:30 +0530)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 13 May 2023 08:33:18 +0000 (17:33 +0900)
Avoid extra 120ms delay during system resume.

The xHC controller may signal wake up to 120ms before showing which usb
device caused the wake on the xHC port registers.

The xhci driver therefore checks for port activity up to 120ms during
resume, making sure that the hub driver can see the port change, and
won't immediately runtime suspend back due to no port activity.

This is however only needed for runtime resume as system resume will
resume all child hubs and other child usb devices anyway.

Fixes: 253f588c70f6 ("xhci: Improve detection of device initiated wake signal.")
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20230428140056.1318981-3-Basavaraj.Natikar@amd.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci.c

index 65d54c8..b81313f 100644 (file)
@@ -1117,7 +1117,7 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg)
                 * the first wake signalling failed, give it that chance.
                 */
                pending_portevent = xhci_pending_portevent(xhci);
-               if (!pending_portevent) {
+               if (!pending_portevent && msg.event == PM_EVENT_AUTO_RESUME) {
                        msleep(120);
                        pending_portevent = xhci_pending_portevent(xhci);
                }