Re: [PATCH v2 2/4] dt-bindings: phy: add imx8 pcie phy driver support

[Lucas Stach <l.stach@pengutronix.de>]

Am Sonntag, dem 26.09.2021 um 15:39 +0800 schrieb Richard Zhu:
> Add dt-binding for the standalone i.MX8 PCIe PHY driver.
> 
> Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
> ---
>  .../bindings/phy/fsl,imx8-pcie-phy.yaml       | 67 +++++++++++++++++++
>  1 file changed, 67 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/fsl,imx8-pcie-phy.yaml
> 
> diff --git a/Documentation/devicetree/bindings/phy/fsl,imx8-pcie-phy.yaml b/Documentation/devicetree/bindings/phy/fsl,imx8-pcie-phy.yaml
> new file mode 100644
> index 000000000000..fd08897fef82
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/fsl,imx8-pcie-phy.yaml
> @@ -0,0 +1,67 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/phy/fsl,imx8-pcie-phy.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Freescale i.MX8 SoC series PCIe PHY Device Tree Bindings
> +
> +maintainers:
> +  - Richard Zhu <hongxing.zhu@nxp.com>
> +
> +properties:
> +  "#phy-cells":
> +    const: 0
> +
> +  compatible:
> +    enum:
> +      - fsl,imx8mm-pcie-phy
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    items:
> +      - description: PHY module clock
> +
> +  clock-names:
> +    items:
> +      - const: phy

The clock name should describe what it is used for in the hardware
block described by the DT node. So I would think this should be called
"ref" or something like this, as I believe this clock is really only
used as the reference clock and can be disabled when the refclock is
supplied via the pad, right?
 
> +
> +  fsl,refclk-pad-mode:
> +    description: |
> +      Specifies the mode of the refclk pad used. It can be NO_USED(PHY
> +      refclock is derived from SoC internal source), INPUT(PHY refclock
> +      is provided externally via the refclk pad) or OUTPUT(PHY refclock
> +      is derived from SoC internal source and provided on the refclk pad).
> +      Refer include/dt-bindings/phy/phy-imx8-pcie.h for the constants
> +      to be used.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [ 0, 1, 2 ]
> +
> +required:
> +  - "#phy-cells"
> +  - compatible
> +  - reg
> +  - clocks
> +  - clock-names
> +  - fsl,refclk-pad-mode
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    #include <dt-bindings/clock/imx8mm-clock.h>
> +
> +    pcie_phy: pcie-phy@32f00000 {
> +            compatible = "fsl,imx8mm-pcie-phy";
> +            reg = <0x32f00000 0x10000>;
> +            clocks = <&clk IMX8MM_CLK_PCIE1_PHY>;
> +            clock-names = "phy";
> +            assigned-clocks = <&clk IMX8MM_CLK_PCIE1_PHY>;
> +            assigned-clock-rates = <100000000>;
> +            assigned-clock-parents = <&clk IMX8MM_SYS_PLL2_100M>;
> +            fsl,refclk-pad-mode = <1>;

Include the new header added in patch 1 and use the enum.

> +            #phy-cells = <0>;
> +    };
> +...