Aw: Re: [PATCH v2] ARM: dts: nitrogen6x: add CAN support

From: Peter Seiderer
Date: Fri May 22 2015 - 15:30:40 EST


Hello Philipp,

> Gesendet: Freitag, 22. Mai 2015 um 13:05 Uhr
> Von: "Philipp Zabel" <p.zabel@xxxxxxxxxxxxxx>
> An: "Peter Seiderer" <ps.report@xxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx, "Mark Rutland" <mark.rutland@xxxxxxx>, devicetree@xxxxxxxxxxxxxxx, "Russell King" <linux@xxxxxxxxxxxxxxxx>, "Pawel Moll" <pawel.moll@xxxxxxx>, "Ian Campbell" <ijc+devicetree@xxxxxxxxxxxxxx>, "Rob Herring" <robh+dt@xxxxxxxxxx>, "Sascha Hauer" <kernel@xxxxxxxxxxxxxx>, "Kumar Gala" <galak@xxxxxxxxxxxxxx>, "Shawn Guo" <shawn.guo@xxxxxxxxxx>, linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Betreff: Re: [PATCH v2] ARM: dts: nitrogen6x: add CAN support
>
> Hi Peter,
>
> Am Donnerstag, den 21.05.2015, 19:45 +0200 schrieb Peter Seiderer:
> > Regulator stuff copied from imx6qdl-tx6.dtsi, pin configuration
> > taken from Boundary Devices linux kernel tree ([1] and [2]).
> >
> > [1] https://github.com/boundarydevices/linux-imx6/blob/boundary-imx_3.10.17_1.0.2_ga/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi
> > [2] https://github.com/boundarydevices/linux-imx6/blob/boundary-imx_3.10.17_1.0.2_ga/arch/arm/boot/dts/imx6qdl.dtsi
> >
> > Signed-off-by: Peter Seiderer <ps.report@xxxxxxx>
> > ---
> > v2:
> > - fix imx6qdl-nitrogen6x.dtsi url
> > - use real PAD settings (suggested by Fabio Estevam)
> > - remove _1 suffix (suggested by Shawn Guo)
> > ---
> > arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi | 32 +++++++++++++++++++++++++++++++
> > 1 file changed, 32 insertions(+)
> >
> > diff --git a/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi b/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi
> > index fd096dc..d40092e 100644
> > --- a/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi
> > +++ b/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi
> > @@ -54,6 +54,17 @@
> > gpio = <&gpio3 22 0>;
> > enable-active-high;
> > };
> > +
> > + reg_can_xcvr: regulator@3 {
> > + compatible = "regulator-fixed";
> > + reg = <3>;
> > + regulator-name = "CAN XCVR";
> > + regulator-min-microvolt = <3300000>;
> > + regulator-max-microvolt = <3300000>;
> > + pinctrl-names = "default";
> > + pinctrl-0 = <&pinctrl_can_xcvr>;
> > + gpio = <&gpio1 2 GPIO_ACTIVE_HIGH>;
>
> According to
> Documentation/devicetree/bindings/regulator/fixed-regulator.txt
> this should have:
> enable-active-high;
>
> instead of the gpio phandle flag (which is ignored). Otherwise an active
> low GPIO is assumed.
>

Thanks for review...

I was a bit confused from the original:

imx6qdl-tx6.dtsi:103: reg_can_xcvr: regulator@3 {
imx6qdl-tx6.dtsi-104- compatible = "regulator-fixed";
imx6qdl-tx6.dtsi-105- reg = <3>;
imx6qdl-tx6.dtsi-106- regulator-name = "CAN XCVR";
imx6qdl-tx6.dtsi-107- regulator-min-microvolt = <3300000>;
imx6qdl-tx6.dtsi-108- regulator-max-microvolt = <3300000>;
imx6qdl-tx6.dtsi-109- pinctrl-names = "default";
imx6qdl-tx6.dtsi:110: pinctrl-0 = <&pinctrl_flexcan_xcvr>;
imx6qdl-tx6.dtsi-111- gpio = <&gpio4 21 GPIO_ACTIVE_HIGH>;
imx6qdl-tx6.dtsi-112- enable-active-low;
imx6qdl-tx6.dtsi-113- };

...and removed the default 'enable-active-low'...

Maybe GPIO_ACTIVE_LOW is the right thing?

>From the other files:

imx28-tx28.dts:90: reg_can_xcvr: regulator@4 {
imx28-tx28.dts-91- compatible = "regulator-fixed";
imx28-tx28.dts-92- reg = <4>;
imx28-tx28.dts-93- regulator-name = "CAN XCVR";
imx28-tx28.dts-94- regulator-min-microvolt = <3300000>;
imx28-tx28.dts-95- regulator-max-microvolt = <3300000>;
imx28-tx28.dts-96- gpio = <&gpio1 0 GPIO_ACTIVE_HIGH>;
imx28-tx28.dts-97- pinctrl-names = "default";
imx28-tx28.dts:98: pinctrl-0 = <&tx28_flexcan_xcvr_pins>;
imx28-tx28.dts-99- };


imx53-tx53.dtsi:90: reg_can_xcvr: regulator@2 {
imx53-tx53.dtsi-91- compatible = "regulator-fixed";
imx53-tx53.dtsi-92- reg = <2>;
imx53-tx53.dtsi-93- regulator-name = "CAN XCVR";
imx53-tx53.dtsi-94- regulator-min-microvolt = <3300000>;
imx53-tx53.dtsi-95- regulator-max-microvolt = <3300000>;
imx53-tx53.dtsi-96- pinctrl-names = "default";
imx53-tx53.dtsi:97: pinctrl-0 = <&pinctrl_can_xcvr>;
imx53-tx53.dtsi-98- gpio = <&gpio4 21 GPIO_ACTIVE_HIGH>;
imx53-tx53.dtsi-99- };

But there are also imx regulator-fixed definitions with GPIO_ACTIVE_HIGH/enable-active-high:

imx28-tx28.dts-101- reg_lcd: regulator@5 {
imx28-tx28.dts-102- compatible = "regulator-fixed";
imx28-tx28.dts-103- reg = <5>;
imx28-tx28.dts-104- regulator-name = "LCD POWER";
imx28-tx28.dts-105- regulator-min-microvolt = <3300000>;
imx28-tx28.dts-106- regulator-max-microvolt = <3300000>;
imx28-tx28.dts-107- gpio = <&gpio1 31 GPIO_ACTIVE_HIGH>;
imx28-tx28.dts-108- enable-active-high;
imx28-tx28.dts-109- };


imx53-tx53.dtsi-101- reg_usbh1_vbus: regulator@3 {
imx53-tx53.dtsi-102- compatible = "regulator-fixed";
imx53-tx53.dtsi-103- reg = <3>;
imx53-tx53.dtsi-104- regulator-name = "usbh1_vbus";
imx53-tx53.dtsi-105- regulator-min-microvolt = <5000000>;
imx53-tx53.dtsi-106- regulator-max-microvolt = <5000000>;
imx53-tx53.dtsi-107- pinctrl-names = "default";
imx53-tx53.dtsi-108- pinctrl-0 = <&pinctrl_usbh1_vbus>;
imx53-tx53.dtsi-109- gpio = <&gpio3 31 GPIO_ACTIVE_HIGH>;
imx53-tx53.dtsi-110- enable-active-high;
imx53-tx53.dtsi-111- };


imx6qdl-tx6.dtsi-115- reg_lcd0_pwr: regulator@4 {
imx6qdl-tx6.dtsi-116- compatible = "regulator-fixed";
imx6qdl-tx6.dtsi-117- reg = <4>;
imx6qdl-tx6.dtsi-118- regulator-name = "LCD0 POWER";
imx6qdl-tx6.dtsi-119- regulator-min-microvolt = <3300000>;
imx6qdl-tx6.dtsi-120- regulator-max-microvolt = <3300000>;
imx6qdl-tx6.dtsi-121- pinctrl-names = "default";
imx6qdl-tx6.dtsi-122- pinctrl-0 = <&pinctrl_lcd0_pwr>;
imx6qdl-tx6.dtsi-123- gpio = <&gpio3 29 GPIO_ACTIVE_HIGH>;
imx6qdl-tx6.dtsi-124- enable-active-high;
imx6qdl-tx6.dtsi-125- regulator-boot-on;
imx6qdl-tx6.dtsi-126- regulator-always-on;
imx6qdl-tx6.dtsi-127- };

Any further advice from your side which solution is the right one?

- GPIO_ACTIVE_HIGH/enable-active-high
- GPIO_ACTIVE_LOW

Regards,
Peter

> regards
> Philipp
>
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/