Re: [net-next PATCH v11 3/9] dt-bindings: net: dsa: Document support for Airoha AN8855 DSA Switch

Vladimir Oltean
2024-12-10T20:49:01Z

On Mon, Dec 09, 2024 at 02:44:20PM +0100, Christian Marangi wrote:
> Document support for Airoha AN8855 5-port Gigabit Switch.
>
> It does expose the 5 Internal PHYs on the MDIO bus and each port
> can access the Switch register space by configurting the PHY page.

typo: configuring
Also below.

>
> Each internal PHY might require calibration with the fused EFUSE on
> the switch exposed by the Airoha AN8855 SoC NVMEM.

This paragraph should be irrelevant to the switch binding.

>
> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> ---
> .../net/dsa/airoha,an8855-switch.yaml | 105 ++++++++++++++++++
> MAINTAINERS | 1 +
> 2 files changed, 106 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/net/dsa/airoha,an8855-switch.yaml
>
> diff --git a/Documentation/devicetree/bindings/net/dsa/airoha,an8855-switch.yaml b/Documentation/devicetree/bindings/net/dsa/airoha,an8855-switch.yaml
> new file mode 100644
> index 000000000000..63bcbebd6a29
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/dsa/airoha,an8855-switch.yaml
> @@ -0,0 +1,105 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/dsa/airoha,an8855-switch.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Airoha AN8855 Gigabit Switch
> +
> +maintainers:
> + - Christian Marangi <ansuelsmth@gmail.com>
> +
> +description: >
> + Airoha AN8855 is a 5-port Gigabit Switch.
> +
> + It does expose the 5 Internal PHYs on the MDIO bus and each port
> + can access the Switch register space by configurting the PHY page.
> +
> + Each internal PHY might require calibration with the fused EFUSE on
> + the switch exposed by the Airoha AN8855 SoC NVMEM.
> +
> +$ref: dsa.yaml#
> +
> +properties:
> + compatible:
> + const: airoha,an8855-switch
> +
> + reset-gpios:
> + description:
> + GPIO to be used to reset the whole device
> + maxItems: 1

Since this affects the whole device, the SoC node (handled by the
MFD driver) should handle it. Otherwise you expose the code to weird
race conditions where one child MFD device resets the whole chip after
the other MFD children have probed, and this undoes their settings.

> +
> + airoha,ext-surge:
> + $ref: /schemas/types.yaml#/definitions/flag
> + description:
> + Calibrate the internal PHY with the calibration values stored in EFUSE
> + for the r50Ohm values.

Doesn't seem that this pertains to the switch.