[PATCH v3 3/6] dt-bindings: clock: imx8mp: Add reset-controller sub-node

[Shengjiu Wang]

On Wed, May 15, 2024 at 10:47 AM Shengjiu Wang <shengjiu.wang at gmail.com> wrote:
>
> On Wed, May 15, 2024 at 5:09 AM Stephen Boyd <sboyd at kernel.org> wrote:
> >
> > Quoting Conor Dooley (2024-05-14 11:06:14)
> > > On Tue, May 14, 2024 at 05:33:27PM +0800, Shengjiu Wang wrote:
> > > > diff --git a/Documentation/devicetree/bindings/clock/imx8mp-audiomix.yaml b/Documentation/devicetree/bindings/clock/imx8mp-audiomix.yaml
> > > > index 0a6dc1a6e122..a403ace4d11f 100644
> > > > --- a/Documentation/devicetree/bindings/clock/imx8mp-audiomix.yaml
> > > > +++ b/Documentation/devicetree/bindings/clock/imx8mp-audiomix.yaml
> > > > @@ -15,7 +15,10 @@ description: |
> > > >
> > > >  properties:
> > > >    compatible:
> > > > -    const: fsl,imx8mp-audio-blk-ctrl
> > > > +    items:
> > > > +      - const: fsl,imx8mp-audio-blk-ctrl
> > > > +      - const: syscon
> > > > +      - const: simple-mfd
> > > >
> > > >    reg:
> > > >      maxItems: 1
> > > > @@ -44,6 +47,11 @@ properties:
> > > >        ID in its "clocks" phandle cell. See include/dt-bindings/clock/imx8mp-clock.h
> > > >        for the full list of i.MX8MP IMX8MP_CLK_AUDIOMIX_ clock IDs.
> > > >
> > > > +  reset-controller:
> > > > +    type: object
> > > > +    $ref: /schemas/reset/fsl,imx8mp-audiomix-reset.yaml#
> > > > +    description: The child reset devices of AudioMIX Block Control.
> > >
> > > Why not just set #reset-cells = <1> in the existing node? IIRC it was
> > > already suggested to you to do that and use auxdev to set up the reset
> > > driver.
> >
> > Yes, do that.
>
> Can I know why sub nodes can't be used? the relationship of parent and
> child devices looks better with sub nodes.
>
> A further question is can I use the reset-ti-syscon? which is a generic reset
> device for SoCs.  with it I don't even need to write a new reset device driver.
> it is more simple.
>
The document link is:
https://www.kernel.org/doc/Documentation/devicetree/bindings/reset/ti-syscon-reset.txt

Then example is:
examples:
  # Clock Control Module node:
  - |
    #include <dt-bindings/clock/imx8mp-clock.h>
    #include <dt-bindings/reset/ti-syscon.h>

    clock-controller at 30e20000 {
        compatible = "fsl,imx8mp-audio-blk-ctrl", "syscon", "simple-mfd";
        reg = <0x30e20000 0x10000>;
        #clock-cells = <1>;
        clocks = <&clk IMX8MP_CLK_AUDIO_ROOT>,
                 <&clk IMX8MP_CLK_SAI1>,
                 <&clk IMX8MP_CLK_SAI2>,
                 <&clk IMX8MP_CLK_SAI3>,
                 <&clk IMX8MP_CLK_SAI5>,
                 <&clk IMX8MP_CLK_SAI6>,
                 <&clk IMX8MP_CLK_SAI7>;
        clock-names = "ahb",
                      "sai1", "sai2", "sai3",
                      "sai5", "sai6", "sai7";
        power-domains = <&pgc_audio>;

        reset-controller {
            compatible = "ti,syscon-reset";
            #reset-cells = <1>;
            ti,reset-bits = <
                0x200 0 0x200 0 0 0 (ASSERT_CLEAR | DEASSERT_SET | STATUS_NONE)
                0x200 1 0x200 1 0 0 (ASSERT_CLEAR | DEASSERT_SET | STATUS_NONE)
            >;
        };
    };

Best regards
Shengjiu Wang