| Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | # SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause |
| 2 | %YAML 1.2 |
| 3 | --- |
| 4 | $id: http://devicetree.org/schemas/thermal/generic-adc-thermal.yaml# |
| 5 | $schema: http://devicetree.org/meta-schemas/core.yaml# |
| 6 | |
| 7 | title: General Purpose Analog To Digital Converter (ADC) based thermal sensor |
| 8 | |
| 9 | maintainers: |
| 10 | - Laxman Dewangan <ldewangan@nvidia.com> |
| 11 | |
| 12 | description: |
| 13 | On some of platforms, thermal sensor like thermistors are connected to |
| 14 | one of ADC channel and sensor resistance is read via voltage across the |
| 15 | sensor resistor. The voltage read across the sensor is mapped to |
| 16 | temperature using voltage-temperature lookup table. |
| 17 | |
| 18 | properties: |
| 19 | compatible: |
| 20 | const: generic-adc-thermal |
| 21 | |
| 22 | '#thermal-sensor-cells': |
| 23 | const: 0 |
| 24 | |
| 25 | io-channels: |
| 26 | maxItems: 1 |
| 27 | |
| 28 | io-channel-names: |
| 29 | const: sensor-channel |
| 30 | |
| 31 | temperature-lookup-table: |
| 32 | description: | |
| 33 | Lookup table to map the relation between ADC value and temperature. |
| 34 | When ADC is read, the value is looked up on the table to get the |
| 35 | equivalent temperature. |
| 36 | |
| 37 | If not specified, driver assumes the ADC channel gives milliCelsius |
| 38 | directly. |
| 39 | $ref: /schemas/types.yaml#/definitions/int32-matrix |
| 40 | items: |
| 41 | items: |
| 42 | - description: Temperature in milliCelsius |
| 43 | - description: ADC read value |
| 44 | |
| 45 | required: |
| 46 | - compatible |
| 47 | - '#thermal-sensor-cells' |
| 48 | - io-channels |
| 49 | - io-channel-names |
| 50 | |
| 51 | additionalProperties: false |
| 52 | |
| 53 | examples: |
| 54 | - | |
| 55 | #include <dt-bindings/thermal/thermal.h> |
| 56 | |
| 57 | thermal-sensor { |
| 58 | compatible = "generic-adc-thermal"; |
| 59 | #thermal-sensor-cells = <0>; |
| 60 | io-channels = <&ads1015 1>; |
| 61 | io-channel-names = "sensor-channel"; |
| 62 | temperature-lookup-table = < |
| 63 | (-40000) 2578 |
| 64 | (-39000) 2577 |
| 65 | (-38000) 2576 |
| 66 | (-37000) 2575 |
| 67 | (-36000) 2574 |
| 68 | (-35000) 2573 |
| 69 | (-34000) 2572 |
| 70 | (-33000) 2571 |
| 71 | (-32000) 2569 |
| 72 | (-31000) 2568 |
| 73 | (-30000) 2567 |
| 74 | /* skip */ |
| 75 | 118000 254 |
| 76 | 119000 247 |
| 77 | 120000 240 |
| 78 | 121000 233 |
| 79 | 122000 226 |
| 80 | 123000 220 |
| 81 | 124000 214 |
| 82 | 125000 208>; |
| 83 | }; |
| 84 | ... |