This patch adds documentation of device-tree bindings for the Gateworks System Controller (GSC).
Signed-off-by: Tim Harvey <thar...@gateworks.com> Reviewed-by: Rob Herring <r...@kernel.org> --- v10: - no changes v9: - added Reviewed-by: Rob Herring <r...@kernel.org> - remove allOf: see https://lkml.org/lkml/2020/4/15/1930 - encorporate Lee's review comments for item descriptions v8: - add register to fan-controller node name v7: - change divider from mili-ohms to ohms - add constraints for voltage divider and offset - remove unnecessary ref for offset - renamed fan to fan-controller and changed base prop to reg v6: - fix typo - drop invalid description from #interrupt-cells property - fix adc pattern property - add unit suffix - replace hwmon/adc with adc/channel - changed adc type to mode and enum int - add unit suffix and drop ref for voltage-divider - moved fan to its own subnode with base register 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 | 196 +++++++++++++++++++++ 1 file changed, 196 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..487a844 --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml @@ -0,0 +1,196 @@ +# 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 + +description: | + The Gateworks System Controller (GSC) is a device present across various + Gateworks product families that provides a set of system related features + such as the following (refer to the board hardware user manuals to see what + features are present) + - Watchdog Timer + - GPIO + - Pushbutton controller + - Hardware monitor with ADC's for temperature and voltage rails and + fan controller + +maintainers: + - Tim Harvey <thar...@gateworks.com> + - Robert Jones <rjo...@gateworks.com> + +properties: + $nodename: + pattern: "gsc@[0-9a-f]{1,2}" + compatible: + const: gw,gsc + + reg: + description: I2C device address + maxItems: 1 + + interrupts: + maxItems: 1 + + interrupt-controller: true + + "#interrupt-cells": + const: 1 + + "#address-cells": + const: 1 + + "#size-cells": + const: 0 + + adc: + type: object + description: Optional hardware monitoring module + + properties: + compatible: + const: gw,gsc-adc + + "#address-cells": + const: 1 + + "#size-cells": + const: 0 + + patternProperties: + "^channel@[0-9]+$": + type: object + description: | + Properties for a single ADC which can report cooked values + (i.e. temperature sensor based on thermister), raw values + (i.e. voltage rail with a pre-scaling resistor divider). + + properties: + reg: + description: Register of the ADC + maxItems: 1 + + label: + description: Name of the ADC input + + gw,mode: + description: | + conversion mode: + 0 - temperature, in C*10 + 1 - pre-scaled voltage value + 2 - scaled voltage based on an optional resistor divider + and optional offset + $ref: /schemas/types.yaml#/definitions/uint32 + enum: [0, 1, 2] + + gw,voltage-divider-ohms: + description: Values of resistors for divider on raw ADC input + maxItems: 2 + items: + minimum: 1000 + maximum: 1000000 + + gw,voltage-offset-microvolt: + description: | + A positive voltage offset to apply to a raw ADC + (i.e. to compensate for a diode drop). + minimum: 0 + maximum: 1000000 + + required: + - gw,mode + - reg + - label + + required: + - compatible + - "#address-cells" + - "#size-cells" + +patternProperties: + "^fan-controller@[0-9a-f]+$": + type: object + description: Optional fan controller + + properties: + compatible: + const: gw,gsc-fan + + "#address-cells": + const: 1 + + "#size-cells": + const: 0 + + reg: + description: The fan controller base address + maxItems: 1 + + required: + - compatible + - reg + - "#address-cells" + - "#size-cells" + +required: + - compatible + - reg + - interrupts + - interrupt-controller + - "#interrupt-cells" + - "#address-cells" + - "#size-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>; + #address-cells = <1>; + #size-cells = <0>; + + adc { + compatible = "gw,gsc-adc"; + #address-cells = <1>; + #size-cells = <0>; + + channel@0 { /* A0: Board Temperature */ + reg = <0x00>; + label = "temp"; + gw,mode = <0>; + }; + + channel@2 { /* A1: Input Voltage (raw ADC) */ + reg = <0x02>; + label = "vdd_vin"; + gw,mode = <1>; + gw,voltage-divider-ohms = <22100 1000>; + gw,voltage-offset-microvolt = <800000>; + }; + + channel@b { /* A2: Battery voltage */ + reg = <0x0b>; + label = "vdd_bat"; + gw,mode = <1>; + }; + }; + + fan-controller@2c { + #address-cells = <1>; + #size-cells = <0>; + compatible = "gw,gsc-fan"; + reg = <0x2c>; + }; + }; + }; -- 2.7.4
