Re: [PATCH] usb: xhci-plat: Enable USB 2.0 hardware LPM support for platform xHCs

[Sarah Sharp <sarah.a.sharp@linux.intel.com>]

Hi Julius,

Thanks for the patch!  Did you test with a USB analyzer to see if the
device was actually going into USB 2.0 Link PM?  I'd like to confirm we
really aren't breaking anything for DW3 hosts by enabling this.

Sarah Sharp

On Tue, Aug 20, 2013 at 04:21:49PM -0700, Julius Werner wrote:
> The driver methods required for hardware LPM have only been added to the
> PCI version of the XHCI driver, for no apparent reason. They seem to
> work just as well with the platform driver, so let's add them to give
> more devices the chance for additional power savings. Tested on the DWC3
> xHC of an Exynos5420.
> 
> Signed-off-by: Julius Werner <jwerner@chromium.org>
> ---
>  drivers/usb/host/xhci-plat.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
> index 51e22bf..7f46b5d 100644
> --- a/drivers/usb/host/xhci-plat.c
> +++ b/drivers/usb/host/xhci-plat.c
> @@ -80,6 +80,10 @@ static const struct hc_driver xhci_plat_xhci_driver = {
>  	.hub_status_data =	xhci_hub_status_data,
>  	.bus_suspend =		xhci_bus_suspend,
>  	.bus_resume =		xhci_bus_resume,
> +
> +	/* LPM support */
> +	.update_device =	xhci_update_device,
> +	.set_usb2_hw_lpm =	xhci_set_usb2_hardware_lpm,
>  };
>  
>  static int xhci_plat_probe(struct platform_device *pdev)
> -- 
> 1.7.12.4
>