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                 4 - fan tach input to report RPM's
  87             $ref: /schemas/types.yaml#/definitions/uint32
  88             enum: [0, 1, 2, 3, 4]
  89
  90           gw,voltage-divider-ohms:
  91             description: Values of resistors for divider on raw ADC input
  92             maxItems: 2
  93             items:
  94               minimum: 1000
  95               maximum: 1000000
  96
  97           gw,voltage-offset-microvolt:
  98             description: |
  99               A positive voltage offset to apply to a raw ADC
 100               (i.e. to compensate for a diode drop).
 101             minimum: 0
 102             maximum: 1000000
 103
 104         required:
 105           - gw,mode
 106           - reg
 107           - label
 108
 109     required:
 110       - compatible
 111       - "#address-cells"
 112       - "#size-cells"
 113
 114 patternProperties:
 115   "^fan-controller@[0-9a-f]+$":
 116     type: object
 117     description: Optional fan controller
 118
 119     properties:
 120       compatible:
 121         const: gw,gsc-fan
 122
 123       "#address-cells":
 124         const: 1
 125
 126       "#size-cells":
 127         const: 0
 128
 129       reg:
 130         description: The fan controller base address
 131         maxItems: 1
 132
 133     required:
 134       - compatible
 135       - reg
 136       - "#address-cells"
 137       - "#size-cells"
 138
 139 required:
 140   - compatible
 141   - reg
 142   - interrupts
 143   - interrupt-controller
 144   - "#interrupt-cells"
 145   - "#address-cells"
 146   - "#size-cells"
 147
 148 additionalProperties: false
 149
 150 examples:
 151   - |
 152     #include <dt-bindings/gpio/gpio.h>
 153     #include <dt-bindings/interrupt-controller/irq.h>
 154     i2c {
 155         #address-cells = <1>;
 156         #size-cells = <0>;
 157
 158         gsc@20 {
 159             compatible = "gw,gsc";
 160             reg = <0x20>;
 161             interrupt-parent = <&gpio1>;
 162             interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
 163             interrupt-controller;
 164             #interrupt-cells = <1>;
 165             #address-cells = <1>;
 166             #size-cells = <0>;
 167
 168             adc {
 169                 compatible = "gw,gsc-adc";
 170                 #address-cells = <1>;
 171                 #size-cells = <0>;
 172
 173                 channel@0 { /* A0: Board Temperature */
 174                     reg = <0x00>;
 175                     label = "temp";
 176                     gw,mode = <0>;
 177                 };
 178
 179                 channel@2 { /* A1: Input Voltage (raw ADC) */
 180                     reg = <0x02>;
 181                     label = "vdd_vin";
 182                     gw,mode = <1>;
 183                     gw,voltage-divider-ohms = <22100 1000>;
 184                     gw,voltage-offset-microvolt = <800000>;
 185                 };
 186
 187                 channel@b { /* A2: Battery voltage */
 188                     reg = <0x0b>;
 189                     label = "vdd_bat";
 190                     gw,mode = <1>;
 191                 };
 192             };
 193
 194             fan-controller@2c {
 195                 #address-cells = <1>;
 196                 #size-cells = <0>;
 197                 compatible = "gw,gsc-fan";
 198                 reg = <0x2c>;
 199             };
 200         };
 201     };