Re: [PATCH v3 2/5] dt-bindings: Add a binding for Mediatek xHCI host controller

[Mark Rutland <mark.rutland@arm.com>]

On Wed, Jul 22, 2015 at 03:05:42PM +0100, Chunfeng Yun wrote:
> add a DT binding documentation of xHCI host controller for the
> MT8173 SoC from Mediatek.
> 
> Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
> ---
>  .../devicetree/bindings/usb/mt8173-xhci.txt        | 50 ++++++++++++++++++++++
>  1 file changed, 50 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/usb/mt8173-xhci.txt
> 
> diff --git a/Documentation/devicetree/bindings/usb/mt8173-xhci.txt b/Documentation/devicetree/bindings/usb/mt8173-xhci.txt
> new file mode 100644
> index 0000000..444494d
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/usb/mt8173-xhci.txt
> @@ -0,0 +1,50 @@
> +MT65XX xhci
> +
> +The device node for Mediatek SOC usb3.0 host controller
> +
> +Required properties:
> + - compatible : supports "mediatek,mt8173-xhci"
> + - reg        : Offset and length of registers

Your example has multiple reg entries.

Please list what each entry is, and the order you expect them in.

> + - interrupts : Interrupt mode, number and trigger mode
> + - power-domains: to enable usb's mtcmos
> + - vusb33-supply:  regulator of usb avdd3.3v
> + - clocks     : must support all clocks that xhci needs
> + - clock-names: should be "sys_mac" for sys and mac clocks, and
> +	"wakeup_deb_p0", "wakeup_deb_p1" for wakeup debounce control
> +	clocks
> + - phys	: the phys that xhci will bind, currently supports up to two
> +	phys, so phy index should not greater than one.
> + - phy-names : should be "phy-X" format, X equals to 0 or 1

This seems somewhat pointless.

> + - usb3-lpm-capable: supports USB3 LPM
> + - mediatek,usb-wakeup: to access usb wakeup control register

What exactly does this property imply?

> + - mediatek,wakeup-src: 1: ip sleep wakeup mode; 2: line state wakeup
> +	mode; others means don't enable wakeup source of usb

This sounds like configuration rather than a hardware property. Why do
you think this needs to be in the DT?

> + - mediatek,u2port-num: the number should not greater than the number
> +	of phys

What exactly does this property imply?

Mark.

> +
> +Optional properties:
> + - vbus-supply : reference to the VBUS regulator;
> +
> +Example:
> +usb: usb30@11270000 {
> +	compatible = "mediatek,mt8173-xhci";
> +	reg = <0 0x11270000 0 0x4000>,
> +	      <0 0x11280000 0 0x0800>;
> +	interrupts = <GIC_SPI 115 IRQ_TYPE_LEVEL_LOW>;
> +	power-domains = <&scpsys MT8173_POWER_DOMAIN_USB>;
> +	clocks = <&topckgen CLK_TOP_USB30_SEL>,
> +		 <&pericfg CLK_PERI_USB0>,
> +		 <&pericfg CLK_PERI_USB1>;
> +	clock-names = "sys_mac",
> +		      "wakeup_deb_p0",
> +		      "wakeup_deb_p1";
> +	phys = <&u3phy 0>, <&u3phy 1>;
> +	phy-names = "phy-0", "phy-1";
> +	vusb33-supply = <&mt6397_vusb_reg>;
> +	vbus-supply = <&usb_p1_vbus>;
> +	usb3-lpm-capable;
> +	mediatek,usb-wakeup = <&pericfg>;
> +	mediatek,wakeup-src = <1>;
> +	mediatek,u2port-num = <2>;
> +	status = "okay";
> +};
> -- 
> 1.8.1.1.dirty
>