Re: [PATCH 1/2] xhci: provide usb_disable_xhci_ports function for Intel chipsets.

[Sergei Shtylyov <sshtylyov@mvista.com>]

Hello.

On 07/23/2012 03:46 PM, Denis Turischev wrote:

> Some devices with Intel Panther Point chipset may require switchover
> usb ports from XHCI back to EHCI controller before shutdown.
> Overwise various BIOS bugs related to power management may be
> triggered.

> Signed-off-by: Denis Turischev <denis@compulab.co.il>
> ---
>  drivers/usb/host/pci-quirks.c |   14 ++++++++++++++
>  drivers/usb/host/pci-quirks.h |    1 +
>  2 files changed, 15 insertions(+)

> diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
> index df0828c..b19a84a 100644
> --- a/drivers/usb/host/pci-quirks.c
> +++ b/drivers/usb/host/pci-quirks.c
> @@ -800,6 +800,20 @@ void usb_enable_xhci_ports(struct pci_dev *xhci_pdev)
>  }
>  EXPORT_SYMBOL_GPL(usb_enable_xhci_ports);
> 
> +void usb_disable_xhci_ports(struct pci_dev *xhci_pdev)
> +{
> +	u32		ports_available;
> +
> +	ports_available = 0x0;

   Why not make it an initializer? And why do you need the variable at all?

> +
> +	pci_write_config_dword(xhci_pdev, USB_INTEL_USB3_PSSEN,
> +			cpu_to_le32(ports_available));

   cpu_to_le32() not needed.

> +
> +	pci_write_config_dword(xhci_pdev, USB_INTEL_XUSB2PR,
> +			cpu_to_le32(ports_available));
> +}
> +EXPORT_SYMBOL_GPL(usb_disable_xhci_ports);
> +
>  /**
>   * PCI Quirks for xHCI.
>   *

WBR, Sergei