[PATCH v3 2/4] dt-bindings: arm: mediatek: Add new bindings of MediaTek frequency hopping

AngeloGioacchino Del Regno angelogioacchino.delregno at collabora.com
Thu Sep 29 06:07:49 PDT 2022


Il 29/09/22 13:46, Johnson Wang ha scritto:
> Add the new binding documentation for MediaTek frequency hopping
> and spread spectrum clocking control.
> 
> Co-developed-by: Edward-JW Yang <edward-jw.yang at mediatek.com>
> Signed-off-by: Edward-JW Yang <edward-jw.yang at mediatek.com>
> Signed-off-by: Johnson Wang <johnson.wang at mediatek.com>
> ---
>   .../arm/mediatek/mediatek,mt8186-fhctl.yaml   | 53 +++++++++++++++++++
>   1 file changed, 53 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml
> 
> diff --git a/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml
> new file mode 100644
> index 000000000000..258dff7ce6bc
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/mediatek/mediatek,mt8186-fhctl.yaml
> @@ -0,0 +1,53 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/arm/mediatek/mediatek,mt8186-fhctl.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: MediaTek frequency hopping and spread spectrum clocking control
> +
> +maintainers:
> +  - Edward-JW Yang <edward-jw.yang at mediatek.com>
> +
> +description: |
> +  Frequency hopping control (FHCTL) is a piece of hardware that control
> +  some PLLs to adopt "hopping" mechanism to adjust their frequency.
> +  Spread spectrum clocking (SSC) is another function provided by this hardware.
> +
> +properties:
> +  compatible:
> +    const: mediatek,mt8186-fhctl
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    description: Phandles of the PLL with FHCTL hardware capability.
> +    minItems: 1
> +    maxItems: 30
> +
> +  mediatek,hopping-ssc-percent:
> +    description: The percentage of spread spectrum clocking for one PLL.
> +    minItems: 1
> +    maxItems: 30
> +    items:
> +      default: 0
> +      minimum: 0
> +      maximum: 8
> +
> +required:
> +  - compatible
> +  - reg
> +  - clocks
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/mt8186-clk.h>
> +    fhctl: fhctl at 1000ce00 {
> +        compatible = "mediatek,mt8186-fhctl";
> +        reg = <0x1000c000 0xe00>;
> +        clocks = <&apmixedsys CLK_APMIXED_MSDCPLL>;
> +        mediatek,hopping-ssc-percent = <3>;
> +    };


.... a more realistic example:

     #include <dt-bindings/clock/mt8186-clk.h>

     soc {
         #address-cells = <2>;
         #size-cells = <2>;

         fhctl: fhctl at 1000ce00 {
             compatible = "mediatek,mt8186-fhctl";
             reg = <0 0x1000c000 0 0xe00>;
             clocks = <&apmixedsys CLK_APMIXED_MSDCPLL>;
             mediatek,hopping-ssc-percent = <3>;
         };
     };

After which...

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno at collabora.com>



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