Documentation/devicetree/bindings/mfd/gateworks-gsc.yaml

   1 # SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
   2 %YAML 1.2
   3 ---
   4 $id: http://devicetree.org/schemas/mfd/gateworks-gsc.yaml#
   5 $schema: http://devicetree.org/meta-schemas/core.yaml#
   6
   7 title: Gateworks System Controller
   8
   9 description: |
  10   The Gateworks System Controller (GSC) is a device present across various
  11   Gateworks product families that provides a set of system related features
  12   such as the following (refer to the board hardware user manuals to see what
  13   features are present)
  14    - Watchdog Timer
  15    - GPIO
  16    - Pushbutton controller
  17    - Hardware monitor with ADC's for temperature and voltage rails and
  18      fan controller
  19
  20 maintainers:
  21   - Tim Harvey <tharvey@gateworks.com>
  22   - Robert Jones <rjones@gateworks.com>
  23
  24 properties:
  25   $nodename:
  26     pattern: "gsc@[0-9a-f]{1,2}"
  27   compatible:
  28     const: gw,gsc
  29
  30   reg:
  31     description: I2C device address
  32     maxItems: 1
  33
  34   interrupts:
  35     maxItems: 1
  36
  37   interrupt-controller: true
  38
  39   "#interrupt-cells":
  40     const: 1
  41
  42   "#address-cells":
  43     const: 1
  44
  45   "#size-cells":
  46     const: 0
  47
  48   adc:
  49     type: object
  50     description: Optional hardware monitoring module
  51
  52     properties:
  53       compatible:
  54         const: gw,gsc-adc
  55
  56       "#address-cells":
  57         const: 1
  58
  59       "#size-cells":
  60         const: 0
  61
  62     patternProperties:
  63       "^channel@[0-9]+$":
  64         type: object
  65         description: |
  66           Properties for a single ADC which can report cooked values
  67           (i.e. temperature sensor based on thermister), raw values
  68           (i.e. voltage rail with a pre-scaling resistor divider).
  69
  70         properties:
  71           reg:
  72             description: Register of the ADC
  73             maxItems: 1
  74
  75           label:
  76             description: Name of the ADC input
  77
  78           gw,mode:
  79             description: |
  80               conversion mode:
  81                 0 - temperature, in C*10
  82                 1 - pre-scaled 24-bit voltage value
  83                 2 - scaled voltage based on an optional resistor divider
  84                     and optional offset
  85                 3 - pre-scaled 16-bit voltage value
  86             $ref: /schemas/types.yaml#/definitions/uint32
  87             enum: [0, 1, 2, 3]
  88
  89           gw,voltage-divider-ohms:
  90             description: Values of resistors for divider on raw ADC input
  91             maxItems: 2
  92             items:
  93               minimum: 1000
  94               maximum: 1000000
  95
  96           gw,voltage-offset-microvolt:
  97             description: |
  98               A positive voltage offset to apply to a raw ADC
  99               (i.e. to compensate for a diode drop).
 100             minimum: 0
 101             maximum: 1000000
 102
 103         required:
 104           - gw,mode
 105           - reg
 106           - label
 107
 108     required:
 109       - compatible
 110       - "#address-cells"
 111       - "#size-cells"
 112
 113 patternProperties:
 114   "^fan-controller@[0-9a-f]+$":
 115     type: object
 116     description: Optional fan controller
 117
 118     properties:
 119       compatible:
 120         const: gw,gsc-fan
 121
 122       "#address-cells":
 123         const: 1
 124
 125       "#size-cells":
 126         const: 0
 127
 128       reg:
 129         description: The fan controller base address
 130         maxItems: 1
 131
 132     required:
 133       - compatible
 134       - reg
 135       - "#address-cells"
 136       - "#size-cells"
 137
 138 required:
 139   - compatible
 140   - reg
 141   - interrupts
 142   - interrupt-controller
 143   - "#interrupt-cells"
 144   - "#address-cells"
 145   - "#size-cells"
 146
 147 examples:
 148   - |
 149     #include <dt-bindings/gpio/gpio.h>
 150     #include <dt-bindings/interrupt-controller/irq.h>
 151     i2c {
 152         #address-cells = <1>;
 153         #size-cells = <0>;
 154
 155         gsc@20 {
 156             compatible = "gw,gsc";
 157             reg = <0x20>;
 158             interrupt-parent = <&gpio1>;
 159             interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
 160             interrupt-controller;
 161             #interrupt-cells = <1>;
 162             #address-cells = <1>;
 163             #size-cells = <0>;
 164
 165             adc {
 166                 compatible = "gw,gsc-adc";
 167                 #address-cells = <1>;
 168                 #size-cells = <0>;
 169
 170                 channel@0 { /* A0: Board Temperature */
 171                     reg = <0x00>;
 172                     label = "temp";
 173                     gw,mode = <0>;
 174                 };
 175
 176                 channel@2 { /* A1: Input Voltage (raw ADC) */
 177                     reg = <0x02>;
 178                     label = "vdd_vin";
 179                     gw,mode = <1>;
 180                     gw,voltage-divider-ohms = <22100 1000>;
 181                     gw,voltage-offset-microvolt = <800000>;
 182                 };
 183
 184                 channel@b { /* A2: Battery voltage */
 185                     reg = <0x0b>;
 186                     label = "vdd_bat";
 187                     gw,mode = <1>;
 188                 };
 189             };
 190
 191             fan-controller@2c {
 192                 #address-cells = <1>;
 193                 #size-cells = <0>;
 194                 compatible = "gw,gsc-fan";
 195                 reg = <0x2c>;
 196             };
 197         };
 198     };