lkml.org 
[lkml]   [2020]   [Jun]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.4 056/178] xhci: Return if xHCI doesn't support LPM
Date
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.com
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
--
2.25.1
\
 
 \ /
  Last update: 2020-06-29 21:58    [W:0.450 / U:0.172 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site