[PATCH 1/2] xhci: Return if xHCI doesn't support LPM
From: Kai-Heng Feng
Date: Wed May 20 2020 - 06:18:22 EST
Just return if xHCI is quirked to disable LPM. We can save some time
from reading registers and doing spinlocks.
Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
---
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 bee5deccc83d..14181a7ea375 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -4390,6 +4390,9 @@ 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;
@@ -4412,7 +4415,7 @@ 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
--
2.17.1