From d6522bc320d7968a7977c30b6f2f3c6d79f1448f Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Wed, 24 Jun 2020 16:59:48 +0300 Subject: [PATCH] xhci: Return if xHCI doesn't support LPM commit f0c472a6da51f9fac15e80fe2fd9c83b68754cff upstream. Just return if xHCI is quirked to disable LPM. We can save some time from reading registers and doing spinlocks. Add stable tag as we want this patch together with the next one, "Poll for U0 after disabling USB2 LPM" which fixes a suspend issue for some USB2 LPM devices Cc: stable@vger.kernel.org Signed-off-by: Kai-Heng Feng Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20200624135949.22611-5-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 13d2971c35445..11a65854d3f09 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4391,6 +4391,9 @@ static int xhci_set_usb2_hardware_lpm(struct usb_hcd *hcd, int hird, exit_latency; int ret; + if (xhci->quirks & XHCI_HW_LPM_DISABLE) + return -EPERM; + if (hcd->speed >= HCD_USB3 || !xhci->hw_lpm_support || !udev->lpm_capable) return -EPERM; @@ -4413,7 +4416,7 @@ static int xhci_set_usb2_hardware_lpm(struct usb_hcd *hcd, xhci_dbg(xhci, "%s port %d USB2 hardware LPM\n", enable ? "enable" : "disable", port_num + 1); - if (enable && !(xhci->quirks & XHCI_HW_LPM_DISABLE)) { + if (enable) { /* Host supports BESL timeout instead of HIRD */ if (udev->usb2_hw_lpm_besl_capable) { /* if device doesn't have a preferred BESL value use a -- 2.51.0