Hi Shawn,
On Sat, Nov 02, 2024 at 12:52:08PM +0800, Shawn Guo wrote:
> On Fri, Oct 25, 2024 at 11:58:02AM +0200, Stefan Eichenberger wrote:
> > From: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx>
> >
> > By default we expect all i2c nodes to be single-master, we do not have
> > any module or carrier board that uses multi-master mode on any i2c
> > controller. With this property set, we benefit from optimisations made
> > exclusively for single-masters.
> >
> > Signed-off-by: Stefan Eichenberger <stefan.eichenberger@xxxxxxxxxxx>
> > ---
> > arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
> > index 5fa3959141911..95d5d2333ca1e 100644
> > --- a/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
> > +++ b/arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi
> > @@ -367,6 +367,7 @@ &i2c1 {
> > pinctrl-1 = <&pinctrl_i2c1_gpio>;
> > scl-gpios = <&gpio5 14 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
> > sda-gpios = <&gpio5 15 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>;
> > + single-master;
>
> Hmm, I do not see this property is documented in i2c-imx bindings.
According to the discussion we had in this thread
https://lore.kernel.org/linux-i2c/2bbddaxyjkxfmlgmq3yqcbzo7dsb2pq5bvdatk2y4ig4iintkt@35btqkdv7sy3/
it is not necessary to have the property documentation in the i2c-imx
binding because it is already documented in the dt-schema:
https://github.com/devicetree-org/dt-schema/blob/main/dtschema/schemas/i2c/i2c-controller.yaml
In the initial discussion, it was addressed for multi-master setups, but
it also applies for single-master. See also this discussion:
https://lore.kernel.org/all/bcdd6cae28edd9dd05a71118f9979e7460688775.camel@xxxxxxxxxxxxxx/
Let me know if I have missed anything or misunderstood.
Regards,
Stefan
