Re: [PATCH v1 1/1] arm64: dts: imx8mn-evk: Pass GPIO_OPEN_DRAIN flag on i2c3 GPIOs

[Stefano Radaelli <stefano.radaelli21@gmail.com>]

On Thu, Oct 15, 2026 at 07:02:48PM +0800, Peng Fan wrote:
> On Thu, Oct 15, 2026 at 10:11:49AM +0200, Stefano Radaelli wrote:
> >From: Stefano Radaelli <stefano.r@variscite.com>
> >
> >scl-gpios and sda-gpios need GPIO_OPEN_DRAIN flag, otherwise the
> >following run-time warning is seen:
> >
> >gpio-146 (scl): enforced open drain please flag it properly in DT/ACPI DSDT/board file
> >
> >Signed-off-by: Stefano Radaelli <stefano.r@variscite.com>
> >---
> > arch/arm64/boot/dts/freescale/imx8mn-evk.dtsi | 4 ++--
> > 1 file changed, 2 insertions(+), 2 deletions(-)
> >
> >diff --git a/arch/arm64/boot/dts/freescale/imx8mn-evk.dtsi b/arch/arm64/boot/dts/freescale/imx8mn-evk.dtsi
> >index 3e590afa4fab..036afa0f6990 100644
> >--- a/arch/arm64/boot/dts/freescale/imx8mn-evk.dtsi
> >+++ b/arch/arm64/boot/dts/freescale/imx8mn-evk.dtsi
> >@@ -287,8 +287,8 @@ &i2c3 {
> > 	pinctrl-names = "default", "gpio";
> > 	pinctrl-0 = <&pinctrl_i2c3>;
> > 	pinctrl-1 = <&pinctrl_i2c3_gpio>;
> >-	scl-gpios = <&gpio5 18 GPIO_ACTIVE_HIGH>;
> >-	sda-gpios = <&gpio5 19 GPIO_ACTIVE_HIGH>;
> >+	scl-gpios = <&gpio5 18 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
> >+	sda-gpios = <&gpio5 19 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
> 
> I think ODE should be configured for pinctrl_i2c3_gpio.
> 
> Regards
> Peng

Hi Peng,

I followed the same approach used in commit
2b1d5d054d29e08926f05cfa30e34d149644585e, as well as in the other i.MX
DTS files that use GPIO_OPEN_DRAIN for I2C bus recovery.

Even in imx8mn-evk.dtsi itself, I2C2 uses the same configuration,
with GPIO_OPEN_DRAIN specified in the GPIO properties and without
ODE enabled in the pinctrl.

Wouldn't introducing a different configuration for I2C3 create some
inconsistency and potentially cause confusion?

If enabling ODE in the pinctrl is the preferred approach, wouldn't it
make more sense to address this in a separate follow-up patch, updating
the existing I2C recovery pinctrl configurations consistently across the
affected DTS files?

What do you think?

Best Regards,
Stefano