RE: [PATCH 4/4] arm64: dts: renesas: rzg3e-smarc-som: Enable I3C

Biju Das
2025-08-07T15:52:38Z

Hi Wolfram Sang,

Thanks for the patch.

> -----Original Message-----
> From: Wolfram Sang <wsa+renesas@sang-engineering.com>
> Sent: 07 August 2025 16:15
> Subject: [PATCH 4/4] arm64: dts: renesas: rzg3e-smarc-som: Enable I3C
>
> Enable I3C on the dedicated connector of the RZ/G3E module. Provide safe defaults allowing to connect
> even to slow I2C devices.
>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
> arch/arm64/boot/dts/renesas/rzg3e-smarc-som.dtsi | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/renesas/rzg3e-smarc-som.dtsi b/arch/arm64/boot/dts/renesas/rzg3e-
> smarc-som.dtsi
> index 7faa44510d98..0c3156129aae 100644
> --- a/arch/arm64/boot/dts/renesas/rzg3e-smarc-som.dtsi
> +++ b/arch/arm64/boot/dts/renesas/rzg3e-smarc-som.dtsi
> @@ -5,6 +5,8 @@
> * Copyright (C) 2024 Renesas Electronics Corp.
> */
>
> +#include <dt-bindings/i3c/i3c.h>
> +
> /*
> * Please set the below switch position on the SoM and the corresponding macro
> * on the board DTS:
> @@ -122,6 +124,12 @@ raa215300: pmic@12 {
> };
> };
>
> +&i3c {
> + i2c-scl-hz = <100000>;
> + i3c-scl-hz = <12500000>;
> + status = "okay";

What about pinctrl settings here?

Also from the pinctrl xsls sheet there is a note. Have you taken care this?

When the pin function I3C is selected :
I3C Bus Interface has a function to switch the pin output to Nch-OpenDrain or CMOS.
Use the register on the I3C Bus Interface to switch the pin output mode.
At this time, the setting value of PFC_NOD.reg should be 0 (N-ch open drain OFF).

Cheers,
Biju