On Mon, Feb 24, 2020 at 12:54:23PM -0800, Tim Harvey wrote:
> This patch adds documentation of device-tree bindings for the
> Gateworks System Controller (GSC).
>
> Signed-off-by: Tim Harvey <tharvey@xxxxxxxxxxxxx>
> ---
> v5:
> - resolve dt_binding_check issues
>
> v4:
> - move to using pwm<n>_auto_point<m>_{pwm,temp} for FAN PWM
> - remove unncessary resolution/scaling properties for ADCs
> - update to yaml
> - remove watchdog
>
> v3:
> - replaced _ with -
> - remove input bindings
> - added full description of hwmon
> - fix unit address of hwmon child nodes
> ---
> .../devicetree/bindings/mfd/gateworks-gsc.yaml | 158 +++++++++++++++++++++
> 1 file changed, 158 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml
>
> diff --git a/Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml b/Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml
> new file mode 100644
> index 00000000..f7c1a05
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml
> @@ -0,0 +1,158 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/gateworks-gsc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Gateworks System Controller multi-function device
> +
> +description: |
> + The GSC is a Multifunction I2C slave device with the following submodules:
> + - Watchdog Timer
> + - GPIO
> + - Pushbutton controller
> + - Hardware Monitore with ADC's for temperature and voltage rails and
typo
> + fan controller
> +
> +maintainers:
> + - Tim Harvey <tharvey@xxxxxxxxxxxxx>
> + - Robert Jones <rjones@xxxxxxxxxxxxx>
> +
> +properties:
> + $nodename:
> + pattern: "gsc@[0-9a-f]{1,2}"
> + compatible:
> + const: gw,gsc
That's not very specific.
> +
> + reg:
> + description: I2C device address
> + maxItems: 1
> +
> + interrupts:
> + maxItems: 1
> +
> + interrupt-controller: true
> +
> + "#interrupt-cells":
> + const: 1
> + description: The IRQ number
description is wrong. You can just drop it.
> +
> + hwmon:
'hwmon' is a Linux thing. I'm suspicious...
> + type: object
> + description: Optional Hardware Monitoring module
> +
> + properties:
> + compatible:
> + const: gw,gsc-hwmon
> +
> + "#address-cells":
> + const: 1
> +
> + "#size-cells":
> + const: 0
> +
> + gw,fan-base:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: The fan controller base address
Shouldn't this be described as a node in the DT or be implied by the
compatible?
> +
> + patternProperties:
> + "^adc@[0-2]$":
There's only one number space at any level. So if you ever need anything
else at this level, it can't have an address. Just something to
consider.
> + type: object
> + description: |
> + Properties for a single ADC which can report cooked values
> + (ie temperature sensor based on thermister), raw values
> + (ie voltage rail with a pre-scaling resistor divider).
> +
> + properties:
> + reg:
> + description: Register of the ADC
> + maxItems: 1
> +
> + label:
> + description: Name of the ADC input
> +
> + type:
Very generic property name, but it's not generic. Needs a vendor prefix
at least.
> + description: |
> + temperature in C*10 (temperature),
> + pre-scaled voltage value (voltage),
> + or scaled based on an optional resistor divider and optional
> + offset (voltage-raw)
> + enum:
> + - temperature
> + - voltage
> + - voltage-raw
> +
> + gw,voltage-divider:
> + allOf:
> + - $ref: /schemas/types.yaml#/definitions/uint32-array
> + description: values of resistors for divider on raw ADC input
> + items:
> + - description: R1
> + - description: R2
Needs a standard unit suffix. With that, you can drop the type
reference.
> +
> + gw,voltage-offset:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description: |
> + A positive uV voltage offset to apply to a raw ADC
> + (ie to compensate for a diode drop).
Needs a unit suffix.
> +
> + required:
> + - type
> + - reg
> + - label
> +
> + required:
> + - compatible
> + - "#address-cells"
> + - "#size-cells"
> +
> +required:
> + - compatible
> + - reg
> + - interrupts
> + - interrupt-controller
> + - "#interrupt-cells"
> +
> +examples:
> + - |
> + #include <dt-bindings/gpio/gpio.h>
> + i2c {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + gsc@20 {
> + compatible = "gw,gsc";
> + reg = <0x20>;
> + interrupt-parent = <&gpio1>;
> + interrupts = <4 GPIO_ACTIVE_LOW>;
> + interrupt-controller;
> + #interrupt-cells = <1>;
> +
> + hwmon {
> + compatible = "gw,gsc-hwmon";
> + #address-cells = <1>;
> + #size-cells = <0>;
> + gw,fan-base = <0x2c>;
> +
> + adc@0 { /* A0: Board Temperature */
> + type = "temperature";
> + reg = <0x00>;
> + label = "temp";
> + };
> +
> + adc@2 { /* A1: Input Voltage (raw ADC) */
> + type = "voltage-raw";
> + reg = <0x02>;
> + label = "vdd_vin";
> + gw,voltage-divider = <22100 1000>;
> + gw,voltage-offset = <800000>;
> + };
> +
> + adc@b { /* A2: Battery voltage */
> + type = "voltage";
> + reg = <0x0b>;
> + label = "vdd_bat";
> + };
> + };
> + };
> + };
> --
> 2.7.4
>
