On Do, 2025-02-13 at 10:08 +0800, Inochi Amaoto wrote: > Some SoCs from Aspeed, Allwinner, Sophgo and Synopsys have > a simple reset controller by toggling bit. It is a hard time > for each device to add its own compatible to the driver. > Since this device share a common design, it is possible to > add a common device to reduce these unnecessary change. > > Add common binding for these kind generic reset controller. > > Signed-off-by: Inochi Amaoto <inochiama@xxxxxxxxx> > --- > .../bindings/reset/reset-simple.yaml | 42 +++++++++++++++++++ > 1 file changed, 42 insertions(+) > create mode 100644 Documentation/devicetree/bindings/reset/reset-simple.yaml > > diff --git a/Documentation/devicetree/bindings/reset/reset-simple.yaml b/Documentation/devicetree/bindings/reset/reset-simple.yaml > new file mode 100644 > index 000000000000..77584e23e8e8 > --- /dev/null > +++ b/Documentation/devicetree/bindings/reset/reset-simple.yaml > @@ -0,0 +1,42 @@ > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/reset/reset-simple.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Generic BIT Reset Controller > + > +maintainers: > + - Inochi Amaoto <inochiama@xxxxxxxxx> > + > +description: > + Some reset controller devices uses a simple method to perform > + assert/deassert by toggling bit. Some SoCs from Aspeed, Allwinner, > + Sophgo and Synopsys have this kind of reset controller instances. I think some properties should be documented that make reset controllers "simple" according to this binding. For example, right now, the reset-simple driver assumes the following: - There is a single, contiguous range of 32-bit registers. - All bits in each register directly control a reset line. - There are no self-deasserting resets. - There are no timing requirements. - The bits are exclusively resets, nothing else. - All bits behave the same, so all reset bits are either active-high or all are active-low. - The bits can be read back, but the read status may be active-low independently from the writes. > +properties: > + compatible: > + enum: > + - reset-simple-high > + - reset-simple-low I wonder if it would be better to have a single compatible: const: reset-simple and a boolean property, e.g. active-low: type: boolean like in leds/common.yaml. Also it should be documented clearly what this means for reads and writes. > + reg: > + maxItems: 1 > + > + "#reset-cells": > + const: 1 > + > +required: > + - compatible > + - reg > + - "#reset-cells" > + > +additionalProperties: false > + > +examples: > + - | > + reset-controller@1000000 { > + compatible = "reset-simple-high"; The example should probably include a SoC specific compatible? regards Philipp
