Re: [PATCH 3/3] ARM: dts: imx28: Add DTS description of imx28 based XEA board

From: Fabio Estevam
Date: Tue Dec 22 2020 - 12:59:23 EST


Hi Lukasz,

On Wed, Nov 25, 2020 at 1:19 PM Lukasz Majewski <lukma@xxxxxxx> wrote:

> diff --git a/arch/arm/boot/dts/imx28-lwe.dtsi b/arch/arm/boot/dts/imx28-lwe.dtsi
> new file mode 100644
> index 000000000000..cb2eb4377d9c
> --- /dev/null
> +++ b/arch/arm/boot/dts/imx28-lwe.dtsi
> @@ -0,0 +1,185 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
> +/*
> + * Copyright 2020
> + * Lukasz Majewski, DENX Software Engineering, lukma@xxxxxxx
> + */
> +
> +/dts-v1/;
> +#include "imx28.dtsi"
> +
> +/ {
> + compatible = "fsl,imx28";

You can drop this one.

> +
> + aliases {
> + spi2 = &ssp3;
> + };
> +
> + chosen {
> + bootargs = "root=/dev/mmcblk0p2 rootfstype=ext4 ro rootwait console=ttyAMA0,115200 panic=1";

You could remove bootargs and let the bootloader pass it.

We usually don't pass bootargs in the i.MX dts files.

> + };
> +
> + memory {

memory@40000000

otherwise you will get dtc build warnings with W=1.

> + reg = <0x40000000 0x08000000>;
> + };
> +
> + regulators {
> + compatible = "simple-bus";
> + #address-cells = <1>;
> + #size-cells = <0>;

No need for this 'regulators' container.

> +
> + reg_3v3: regulator@0 {

reg_3v3: regulator-reg-3v3 {

> + compatible = "regulator-fixed";
> + reg = <0>;

Remove the reg = <0>

Same applies to other regulators.

> + reg_usb_5v: regulator@1 {
> + compatible = "regulator-fixed";
> + reg = <1>;
> + regulator-name = "usb_vbus";
> + regulator-min-microvolt = <5000000>;
> + regulator-max-microvolt = <5000000>;
> + enable-active-high;

Why passing 'enable-active-high' when this is not gpio controlled?

> + };
> +
> + reg_fec_3v3: regulator@2 {
> + compatible = "regulator-fixed";
> + reg = <2>;
> + regulator-name = "fec-phy";
> + regulator-min-microvolt = <3300000>;
> + regulator-max-microvolt = <3300000>;
> + enable-active-high;

Same here.

> +&ssp3 {
> + compatible = "fsl,imx28-spi";
> + pinctrl-names = "default";
> + pinctrl-0 = <&spi3_pins_a>;
> + status = "okay";
> +
> + flash0: s25fl256s0@0 {

Node names should be generic

flash@0
> +
> +/dts-v1/;
> +#include "imx28-lwe.dtsi"
> +
> +/ {
> + model = "XEA";

compatible = "xea,imx20-lwe", "fsl,imx28";

You should add xea to the vendor prefix in a separate patch.

You also need to add thie board to
Documentation/devicetree/bindings/arm/fsl.yaml