[PATCH v1 1/3] dt-bindings: mmc: rockchip-dw-mshc: add rockchip,disable-runtime-pm
Krzysztof Kozlowski
krzk at kernel.org
Sun Jan 11 01:41:42 PST 2026
On Sat, Jan 10, 2026 at 02:07:13AM +0100, Marco Schirrmeister wrote:
> Add a new 'rockchip,disable-runtime-pm' property to allow boards to
> inhibit runtime power management. This is required for boards like the
> NanoPi R76S where the bus timing becomes unstable if the controller
> is runtime-suspended during idle periods.
>
> Signed-off-by: Marco Schirrmeister <mschirrmeister at gmail.com>
> ---
> .../devicetree/bindings/mmc/rockchip-dw-mshc.yaml | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.yaml b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.yaml
> index acb9fb9a92cd..41f2644ca2ef 100644
> --- a/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.yaml
> +++ b/Documentation/devicetree/bindings/mmc/rockchip-dw-mshc.yaml
> @@ -100,6 +100,14 @@ properties:
> If not specified, the host will do tuning for 360 times,
> namely tuning for each degree.
>
> + rockchip,disable-runtime-pm:
> + type: boolean
> + description:
> + Inhibit runtime power management. This is required for boards
What is runtime power management? Like Linux PM? If anything phrased
like that is it is a clear no go. Bindings describe hardware.
> + where the bus timing becomes unstable if the controller is
> + runtime-suspended.
You described the desired Linux feature or behavior, not the actual
hardware. The bindings are about the latter, so instead you need to
rephrase the property and its description to match actual hardware
capabilities/features/configuration etc.
Best regards,
Krzysztof
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