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 | |
| parent | fb9bbce6e67a2c33a1902380b1c3d3d96e75af52 (diff) | |
| download | blackbird-op-linux-4750bc78efdb126ddc40f1b34dbae7ce319344cb.tar.gz blackbird-op-linux-4750bc78efdb126ddc40f1b34dbae7ce319344cb.zip | |
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')
| -rw-r--r-- | drivers/usb/host/xhci-plat.c | 3 | ||||
| -rw-r--r-- | drivers/usb/host/xhci.c | 2 | ||||
| -rw-r--r-- | drivers/usb/host/xhci.h | 1 |
3 files changed, 5 insertions, 1 deletions
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c index 163bafde709f..d0625faee8f7 100644 --- a/drivers/usb/host/xhci-plat.c +++ b/drivers/usb/host/xhci-plat.c @@ -259,6 +259,9 @@ static int xhci_plat_probe(struct platform_device *pdev) goto disable_clk; } + if (device_property_read_bool(sysdev, "usb2-lpm-disable")) + xhci->quirks |= XHCI_HW_LPM_DISABLE; + if (device_property_read_bool(sysdev, "usb3-lpm-capable")) xhci->quirks |= XHCI_LPM_SUPPORT; 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 diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 2abaa4d6d39d..dc22392711e3 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1828,6 +1828,7 @@ struct xhci_hcd { #define XHCI_LIMIT_ENDPOINT_INTERVAL_7 (1 << 26) #define XHCI_U2_DISABLE_WAKE (1 << 27) #define XHCI_ASMEDIA_MODIFY_FLOWCONTROL (1 << 28) +#define XHCI_HW_LPM_DISABLE (1 << 29) unsigned int num_active_eps; unsigned int limit_active_eps; |
