From: Kai-Heng Feng kai.heng.feng@canonical.com
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 kai.heng.feng@canonical.com Signed-off-by: Mathias Nyman mathias.nyman@linux.intel.com Link: https://lore.kernel.org/r/20200624135949.22611-5-mathias.nyman@linux.intel.c... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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