Re: [PATCH 1/9] dt-bindings: mfd: Add Marvell AP806/CP110 system controller schema

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Medium] dt-bindings: mfd: marvell,ap806-system-controller collides
  with legacy driver
--

commit 4cddea2359377a9e6ae88c719cab7c7efc9634bf
Author: Rob Herring (Arm) <robh@kernel.org>

dt-bindings: mfd: Add Marvell AP806/CP110 system controller schema

This commit adds a dedicated Device Tree binding schema for the Marvell
AP806 and CP110 system controllers and their child devices.

> diff --git a/Documentation/devicetree/bindings/mfd/marvell,ap806-cp110-system-controller.yaml b/Documentation/devicetree/bindings/mfd/marvell,ap806-cp110-system-controller.yaml
> new file mode 100644
> index 0000000000000..4c43986c2c0a3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/marvell,ap806-cp110-system-controller.yaml
> @@ -0,0 +1,59 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/marvell,ap806-cp110-system-controller.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Marvell AP806 and CP110 system controller
> +
> +maintainers:
> +  - Andrew Lunn <andrew@lunn.ch>
> +  - Gregory Clement <gregory.clement@bootlin.com>
> +  - Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
> +
> +properties:
> +  compatible:
> +    items:
> +      - enum:
> +          - marvell,ap806-system-controller
> +          - marvell,cp110-system-controller
> +      - const: syscon
> +      - const: simple-mfd

[Severity: Medium]
Does requiring marvell,ap806-system-controller on the parent simple-mfd
node cause a collision with the built-in legacy clock driver?

Unlike CP110, where cp110_syscon_legacy_of_match matches
marvell,cp110-system-controller0, ap806_syscon_legacy_of_match matches
marvell,ap806-system-controller:

drivers/clk/mvebu/ap806-system-controller.c:
static const struct of_device_id ap806_syscon_legacy_of_match[] = {
	{ .compatible = "marvell,ap806-system-controller", },
	{ }
};

When a device tree conforms to this schema, ap806_syscon_legacy_driver
binds to the parent MFD platform_device at boot.
ap806_syscon_legacy_probe() then logs three false FW_WARN messages about a
legacy binding, performs an unintended regmap_read() of AP806_SAR_REG
(0x400) in ap806_syscon_common_probe(), and fails probe with -EINVAL and
"compatible not supported" because the parent node is not compatible with
marvell,ap806-clock or marvell,ap807-clock.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261111-dtbs-marvell-v1-0-938788aff3ae@kernel.org?part=1