Re: [PATCH] driver: bus: simple-pm-bus: Add Freescale i.MX8qm/qxp CSR compatible strings

From: Geert Uytterhoeven
Date: Wed Jan 25 2023 - 04:05:29 EST


Hi Liu,

On Wed, Jan 25, 2023 at 9:31 AM Liu Ying <victor.liu@xxxxxxx> wrote:
> Freescale i.MX8qm/qxp CSR module matches with what the simple power
> managed bus driver does, considering it needs an IPG clock to be
> enabled before accessing it's child devices, the child devices need
> to be populated by the CSR module and the child devices' power
> management operations need to be propagated to their parent devices.
> Add the CSR module's compatible strings to simple_pm_bus_of_match[]
> table to support the CSR module.
>
> Suggested-by: Rob Herring <robh@xxxxxxxxxx>
> Suggested-by: Lee Jones <lee@xxxxxxxxxx>
> Signed-off-by: Liu Ying <victor.liu@xxxxxxx>

Thanks for your patch!

> ---
> The CSR module's dt-binding documentation can be found at
> Documentation/devicetree/bindings/mfd/fsl,imx8qxp-csr.yaml.
>
> Suggested by Rob and Lee in this thread:
> https://patchwork.kernel.org/project/linux-arm-kernel/patch/20221017075702.4182846-1-victor.liu@xxxxxxx/
>
> drivers/bus/simple-pm-bus.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/drivers/bus/simple-pm-bus.c b/drivers/bus/simple-pm-bus.c
> index 7afe1947e1c0..4a7575afe6c6 100644
> --- a/drivers/bus/simple-pm-bus.c
> +++ b/drivers/bus/simple-pm-bus.c
> @@ -120,6 +120,8 @@ static const struct of_device_id simple_pm_bus_of_match[] = {
> { .compatible = "simple-mfd", .data = ONLY_BUS },
> { .compatible = "isa", .data = ONLY_BUS },
> { .compatible = "arm,amba-bus", .data = ONLY_BUS },
> + { .compatible = "fsl,imx8qm-lvds-csr", },
> + { .compatible = "fsl,imx8qxp-mipi-lvds-csr", },

I did read the thread linked above, and I still think you should just
add "simple-pm-bus" to the compatible value in DTS, so no driver change
is needed, cfr. Documentation/devicetree/bindings/bus/renesas,bsc.yaml.

If that doesn't work due to DT binding constraints, the latter should
be fixed.

> { /* sentinel */ }
> };
> MODULE_DEVICE_TABLE(of, simple_pm_bus_of_match);

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds