Re: [PATCH v1 4/6] ARM: dts: hpe: Add I2C Topology

From: Krzysztof Kozlowski
Date: Sat Dec 17 2022 - 05:58:52 EST


On 16/12/2022 19:35, nick.hawkins@xxxxxxx wrote:
> From: Nick Hawkins <nick.hawkins@xxxxxxx>
>
> Add 9 I2C Engines, 2 MUXs, and a EEPROM to the device tree.
>
> Signed-off-by: Nick Hawkins <nick.hawkins@xxxxxxx>
> ---
> arch/arm/boot/dts/hpe-bmc-dl360gen10.dts | 72 ++++++++++++++
> arch/arm/boot/dts/hpe-gxp.dtsi | 115 +++++++++++++++++++++++
> 2 files changed, 187 insertions(+)
>
> diff --git a/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts b/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
> index 3a7382ce40ef..d9008e2cfed3 100644
> --- a/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
> +++ b/arch/arm/boot/dts/hpe-bmc-dl360gen10.dts
> @@ -23,4 +23,76 @@
> device_type = "memory";
> reg = <0x40000000 0x20000000>;
> };
> +
> + i2cmux@4 {
> + compatible = "i2c-mux-reg";
> + i2c-parent = <&i2c4>;
> + reg = <0xd1000074 1>;

Did you check this? `dtbs_check` and `dtbs W=1`? Reg looks different
than unit.

> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + i2c4@1 {

Node names should be generic.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

i2c@

> + reg = <1>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> +> + i2c4@3 {

Node names should be generic.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> + reg = <3>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> +
> + i2c4@4 {

Node names should be generic.
https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#generic-names-recommendation

> + reg = <4>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> + };
> +
> + i2cmux@6 {
> + compatible = "i2c-mux-reg";
> + i2c-parent = <&i2c6>;
> + reg = <0xd1000076 1>;

Same question.

> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + i2c6@1 {

and so on...

> + reg = <1>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> +
> + i2c6@2 {
> + reg = <2>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> +
> + i2c6@3 {
> + reg = <3>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> +
> + i2c6@4 {
> + reg = <4>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> +
> + i2c6@5 {
> + reg = <5>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + };
> + };
> +};
> +
> +&i2c2 {
> + eeprom@50 {
> + compatible = "atmel,24c02";
> + pagesize = <8>;
> + reg = <0x50>;
> + };
> };
> diff --git a/arch/arm/boot/dts/hpe-gxp.dtsi b/arch/arm/boot/dts/hpe-gxp.dtsi
> index cf735b3c4f35..27e68932021c 100644
> --- a/arch/arm/boot/dts/hpe-gxp.dtsi
> +++ b/arch/arm/boot/dts/hpe-gxp.dtsi
> @@ -122,6 +122,121 @@
> interrupts = <6>;
> interrupt-parent = <&vic0>;
> };
> +
> + sysreg_system_controller: syscon@f8 {
> + compatible = "hpe,gxp-sysreg", "syscon";
> + reg = <0xf8 0x8>;
> + };
> +
> + i2c0: i2c@2000 {
> + compatible = "hpe,gxp-i2c";
> + reg = <0x2000 0x70>;
> + interrupts = <9>;
> + interrupt-parent = <&vic0>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + hpe,sysreg-phandle = <&sysreg_system_controller>;
> + hpe,i2c-max-bus-freq = <100000>;

Busses should stay disabled in DTSI and only enabled by specific board,
when needed.

> + };
> +
> + i2c1: i2c@2100 {
> + compatible = "hpe,gxp-i2c";
> + reg = <0x2100 0x70>;
> + interrupts = <9>;
> + interrupt-parent = <&vic0>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> + hpe,sysreg-phandle = <&sysreg_system_controller>;
> + hpe,i2c-max-bus-freq = <100000>;
> + };
> +

Best regards,
Krzysztof