Re: [PATCH 2/3] arm64: dts: renesas: r9a09g047: Add missing I2C clock-frequency

Tommaso Merciai <[email protected]> Mon, 3 Aug 2026 18:18:28 +0200
Newsgroups org.kernel.vger.linux-renesas-soc,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel,org.kernel.vger.linux-sound
Message-ID <anC_VPGuGhgyNJXF@tom-desktop>
Hi Krzysztof,
Thanks for your review.

On Mon, Aug 03, 2026 at 03:33:40PM +0200, Krzysztof Kozlowski wrote:
> On 03/08/2026 15:28, Tommaso Merciai wrote:
> > clock-frequency is a required property of the renesas,riic binding, but
> > it is not set in any of the I2C nodes, so dtbs_check fails on boards
> > that enable an I2C controller without providing a rate:
> > 
> >   r9a09g047e57-smarc.dtb: i2c@14400800 (renesas,riic-r9a09g047):
> >   'clock-frequency' is a required property
> > 
> > Add the standard mode rate (100 kHz) to all I2C nodes. Boards that
> > need a faster bus can still override it.
> 
> Why? Binding looks wrong. It clearly says that property can be missing
> and is required.

Good catch, I missed this.

Looking closer, the description is correct: i2c-riic calls
i2c_parse_fw_timings() with use_defaults set, so the core falls back to
I2C_MAX_STANDARD_MODE_FREQ when the property is absent.

So the right fix is to drop clock-frequency from the required
properties instead. I will do that in v2.

Kind regards,
Tommaso

> 
> 
> Best regards,
> Krzysztof