linux-kernel - Re: [PATCH 2/5] ARM: dtsi: sunxi: add common VBUS regulator

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <20141030164125.GO21251@lukather>
Date:	Thu, 30 Oct 2014 17:41:25 +0100
From:	Maxime Ripard <maxime.ripard@...e-electrons.com>
To:	Roman Byshko <rbyshko@...il.com>
Cc:	linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	devicetree@...r.kernel.org, Kishon Vijay Abraham I <kishon@...com>,
	Russell King <linux@....linux.org.uk>,
	Kumar Gala <galak@...eaurora.org>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Mark Rutland <mark.rutland@....com>,
	Pawel Moll <pawel.moll@....com>,
	Rob Herring <robh+dt@...nel.org>
Subject: Re: [PATCH 2/5] ARM: dtsi: sunxi: add common VBUS regulator

Hi,

On Wed, Oct 29, 2014 at 09:13:50PM +0100, Roman Byshko wrote:
> Hi Maxime,
> 
> thank you for the review!
> 
> On Tue, Oct 28, 2014 at 10:51 PM, Maxime Ripard
> <maxime.ripard@...e-electrons.com> wrote:
> > On Mon, Oct 27, 2014 at 10:43:02PM +0100, Roman Byshko wrote:
> >> Until now the regulator nodes for powering USB VBUS
> >> existed only for the two host controllers. Now the regulator
> >> is added for USB OTG too.
> >> ---
> >>  arch/arm/boot/dts/sunxi-common-regulators.dtsi | 19 +++++++++++++++++++
> >>  1 file changed, 19 insertions(+)
> >>
> >> diff --git a/arch/arm/boot/dts/sunxi-common-regulators.dtsi b/arch/arm/boot/dts/sunxi-common-regulators.dtsi
> >> index c9c5b10..f521672 100644
> >> --- a/arch/arm/boot/dts/sunxi-common-regulators.dtsi
> >> +++ b/arch/arm/boot/dts/sunxi-common-regulators.dtsi
> >> @@ -21,6 +21,13 @@
> >>                               allwinner,pull = <0>;
> >>                       };
> >>
> >> +                     usb0_vbus_pin_a: usb0_vbus_pin@0 {
> >> +                             allwinner,pins = "PB9";
> >> +                             allwinner,function = "gpio_out";
> >> +                             allwinner,drive = <0>;
> >> +                             allwinner,pull = <0>;
> >> +                     };
> >> +
> >>                       usb1_vbus_pin_a: usb1_vbus_pin@0 {
> >>                               allwinner,pins = "PH6";
> >>                               allwinner,function = "gpio_out";
> >> @@ -49,6 +56,18 @@
> >>               status = "disabled";
> >>       };
> >>
> >> +     reg_usb0_vbus: usb0-vbus {
> >> +             compatible = "regulator-fixed";
> >> +             pinctrl-names = "default";
> >> +             pinctrl-0 = <&usb0_vbus_pin_a>;
> >> +             regulator-name = "usb0-vbus";
> >> +             regulator-min-microvolt = <5000000>;
> >> +             regulator-max-microvolt = <5000000>;
> >> +             enable-active-high;
> >> +             gpio = <&pio 1 9 0>;
> >> +             status = "disabled";
> >> +     };
> >
> > We're using these regulators because a huuuge majority of the boards
> > out there, regardless of their SoC, are using the same GPIO to drive
> > the same regulator. Is this the case here? What board have you looked
> > at?
> 
> Currently I'm developing and testing for Cubietruck. I also have a few
> other boards (with different SoC), I will add corresponding DT nodes
> for them later.
> 
> As for GPIO which is used to drive the USB0 VBUS pin.
> 
> $ git remote show origin
> * remote origin
>   Fetch URL: https://github.com/linux-sunxi/sunxi-boards.git
>   Push  URL: https://github.com/linux-sunxi/sunxi-boards.git
> ...
> $ grep -A7 usbc0 -r . | grep usb_drv_vbus_gpio | grep port | sort |
> cut -d: -f2 | cut -d "<" -f1 | sort | uniq -c
>       1 PA16
>       1 PA17
>      67 PB09
>       4 PB10
>       1 PB9
>       1 PC17
>       1 PD25
>       4 PG11
>      21 PG12
>       1 PG13
>       1 PH17
>       4 power4
> 
> So PB09 is most often used. PG12 is used on (alsmost always) A13. So
> propose to make PB09 default, then override it in sun5i-a13.dtsi and
> later in board dts file if needed.
> 
> Cubietruck uses PH17. That is why I override PB09 in its dts file.
> 
> Sounds good?

It does :)

Thanks!
Maxime

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

Download attachment "signature.asc" of type "application/pgp-signature" (820 bytes)