diff options
author | Thang Q. Nguyen <tqnguyen@apm.com> | 2017-10-05 11:21:37 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-10-05 11:01:57 +0200 |
commit | 4750bc78efdb126ddc40f1b34dbae7ce319344cb (patch) | |
tree | e8beed27b739a1fafe3736d47b579c173f26dd2a /drivers/usb/host/xhci.c | |
parent | fb9bbce6e67a2c33a1902380b1c3d3d96e75af52 (diff) |
usb: host: xhci support option to disable the xHCI USB2 HW LPM
XHCI specification 1.1 does not require xHCI-compliant controllers
to always enable hardware USB2 LPM. However, the current xHCI
driver always enable it when seeing HLC=1.
This patch supports an option for users to control disabling
USB2 Hardware LPM via DT/ACPI attribute.
This option is needed in case user would like to disable this
feature. For example, their xHCI controller has its USB2 HW LPM
broken.
Signed-off-by: Tung Nguyen <tunguyen@apm.com>
Signed-off-by: Thang Q. Nguyen <tqnguyen@apm.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/xhci.c')
-rw-r--r-- | drivers/usb/host/xhci.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index b2ff1ff1a02f..3a8e75f6898f 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -4087,7 +4087,7 @@ 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) { + if (enable && !(xhci->quirks & XHCI_HW_LPM_DISABLE)) { /* 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 |