Re: [PATCH 2/2] arm64: dts: renesas: r9a09g047e57-smarc: Add overlay for P3T1085UK-ARD

[Wolfram Sang <wsa+renesas@sang-engineering.com>]

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Hi Tommaso,

> +/*
> + * #define I3C_BUS_MODE_PURE 1 (for I3C bus mode pure - default)
> + * #define I3C_BUS_MODE_PURE 0 (for I3C bus mode mixed-fast)
> + */
> +#define I3C_BUS_MODE_PURE	1

Sorry, but I really think this is configuration and not hardware
description. The board has only I3C capable devices, so unless you
connect more devices externally, you can always use pure-i3c-mode.
Enforcing mixed-mode is only for debugging.

> +
> +#if I3C_BUS_MODE_PURE
> +&i3c {
> +	i2c-scl-hz = <400000>;
> +	i3c-scl-hz = <12500000>;
> +	status = "okay";
> +};

So, the above is all that is needed. Which is the basic enablement for
the I3C bus in general. I mean, auto-detecting devices is a key feature
of I3C :) Which basically means IMHO that this overlay is superfluous.


> +#else /* I3C_BUS_MODE_MIXED_FAST */
> +&i3c {
> +	status = "okay";
> +
> +	#address-cells = <1>;
> +	#size-cells = <0>;
> +
> +	i2c-scl-hz = <400000>;
> +	i3c-scl-hz = <12500000>;

Despite this else block being debug only...

> +
> +	eeprom@1a {
> +		compatible = "atmel,24c02";
> +		reg = <0x1a 0 (I2C_FM | I2C_FILTER)>;
> +	};

... there is no device listening to 0x1a on this board? What do you see
there? Did I forget something?

> +
> +	/* U2 */
> +	temperature-sensor@48 {
> +		compatible = "nxp,p3t1085";
> +		reg = <0x48 0 (I2C_FM | I2C_FILTER)>;
> +	};
> +
> +	/* U1 NOT MOUNTED as default */
> +	temp-sense@4c {
> +		status = "disabled";
> +		compatible = "national,lm75";

Yes, mounting U1 is a hack I introduced. The compatible should be
"nxp,p3t1755" BTW. But as said, the whole MIXED_MODE block is not
hardware description, I'd say.

Happy hacking,

   Wolfram


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