Re: usb:xhci: support disable usb2 LPM Remote Wakeup

From: Rob Herring
Date: Fri Dec 09 2016 - 16:36:36 EST


On Sun, Dec 04, 2016 at 07:42:01PM +0700, Thang Q. Nguyen wrote:
> From: Thang Nguyen <tqnguyen@xxxxxxx>
>
> As per USB 2.0 link power management addendum ECN, table 1-2, page 4,
> device or host initiated via resume signaling; device-initiated resumes
> can be optionally enabled/disabled by software. This patch adds support
> to control enabling the USB2 RWE feature via DT/ACPI attribute.
>
> Signed-off-by: Vu Nguyen <vnguyen@xxxxxxx>
> Signed-off-by: Thang Nguyen <tqnguyen@xxxxxxx>
> ---
> Documentation/devicetree/bindings/usb/usb-xhci.txt | 1 +
> drivers/usb/host/xhci-plat.c | 3 +++
> drivers/usb/host/xhci.c | 5 ++++-
> drivers/usb/host/xhci.h | 1 +
> 4 files changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/usb/usb-xhci.txt b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> index 966885c..9b4cd14 100644
> --- a/Documentation/devicetree/bindings/usb/usb-xhci.txt
> +++ b/Documentation/devicetree/bindings/usb/usb-xhci.txt
> @@ -25,6 +25,7 @@ Required properties:
>
> Optional properties:
> - clocks: reference to a clock
> + - usb2-rwe-disable: disable USB2 LPM Remote Wakeup capable

Remote wakeup has been around since USB 1.0 days. Does this need to be
USB2 or XHCI specific?

> - usb3-lpm-capable: determines if platform is USB3 LPM capable
>
> Example: