[PATCH 1/2] ARM: dts: sun9i: cubieboard4: Enable USB support

Maxime Ripard maxime.ripard at free-electrons.com
Fri May 8 04:40:40 PDT 2015


On Fri, May 08, 2015 at 04:01:14PM +0800, Chen-Yu Tsai wrote:
> >> +&ehci0 {
> >> +     status = "okay";
> >> +};
> >> +
> >> +&ehci2 {
> >> +     status = "okay";
> >> +};
> >> +
> >> +/* usb1 is connected to a GL850G USB hub chip, so no need to enable OHCI */
> >
> > You're mentionning usb1, but I don't see it enabled anywhere, is that
> > a typo?
> 
> usb1 (or usbphy1) == ehci/ohci0. usb0 is otg.
> 
> This numbering matches the fex files, and (mostly) matches the
> specs.

Ok, having this comment between ehci2 and ohci2 is confusing then :)

It's not the first board that has a hub, we usually don't really care
as it's kind of obvious. Maybe we can just remove it?

> >>  &mmc0 {
> >> @@ -92,8 +130,30 @@
> >>       status = "okay";
> >>  };
> >>
> >> +&reg_usb1_vbus {
> >> +     pinctrl-0 = <&usb1_vbus_pin_cubieboard4>;
> >> +     gpio = <&pio 7 14 GPIO_ACTIVE_HIGH>; /* PH14 */
> >> +     status = "okay";
> >> +};
> >> +
> >>  &uart0 {
> >>       pinctrl-names = "default";
> >>       pinctrl-0 = <&uart0_pins_a>;
> >>       status = "okay";
> >>  };
> >> +
> >> +&usbphy1 {
> >> +     phy-supply = <&reg_usb1_vbus>;
> >> +     status = "okay";
> >> +};
> >> +
> >> +/*
> >> + * Unfortunately reg_usb1_vbus also powers one of the ports from usb3's hub.
> >> + * One should always make sure both regulators are enabled and working for
> >> + * all USB ports to have power.
> >> + */
> >
> > Can't we just provide the two regulators, and enable both of them so
> > that we know that we always have the needed regulators enabled,
> > disregarding which USB port is used?
> 
> Would setting "always-on" for both regulators work for you?
> Or maybe just the one that's used by both USB hosts?

I was more thinking of giving to the phy an additional regulator, so
that it would enable both the regulators needed to power up all ports.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
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