cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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ntc-thermistor.yaml (4860B)

      1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
      2---
      3$id: http://devicetree.org/schemas/hwmon/ntc-thermistor.yaml#
      4$schema: http://devicetree.org/meta-schemas/core.yaml#
      5
      6title: NTC thermistor temperature sensors
      7
      8maintainers:
      9  - Naveen Krishna Chatradhi <ch.naveen@samsung.com>
     10  - Linus Walleij <linus.walleij@linaro.org>
     11
     12description: |
     13  Thermistors with negative temperature coefficient (NTC) are resistors that
     14  vary in resistance in an often non-linear way in relation to temperature.
     15  The negative temperature coefficient means that the resistance decreases
     16  as the temperature rises. Since the relationship between resistance and
     17  temperature is non-linear, software drivers most often need to use a look
     18  up table and interpolation to get from resistance to temperature.
     19
     20  When used in practice, a thermistor is often connected between ground, a
     21  pull-up resistor or/and a pull-down resistor and a fixed voltage like this:
     22
     23      + e.g. 5V = pull-up voltage (puv)
     24      |
     25     +-+
     26     | |
     27     | | Pull-up resistor
     28     | | (puo)
     29     +-+
     30      |-------------------------o
     31     +-+ |                      ^
     32     | |/                       |
     33     | /                        |
     34     |/| Thermistor             | Measured voltage (mv)
     35     / |                        | "connected ground"
     36    /| |                        |
     37     +-+                        |
     38      |-------------------------o
     39     +-+                        ^
     40     | |                        |
     41     | | Pull-down resistor     | Measured voltage (mv)
     42     | | (pdo)                  | "connected positive"
     43     +-+                        |
     44      |                         |
     45      |                         v
     46      + GND                     GND
     47
     48  The arrangements of where we measure the voltage over the thermistor are
     49  called "connected ground" and "connected positive" and shall be understood as
     50  the cases when either pull-up or pull-down resistance is zero.
     51
     52  If the pull-up resistance is 0 one end of the thermistor is connected to the
     53  positive voltage and we get the thermistor on top of a pull-down resistor
     54  and we take the measure between the thermistor and the pull-down resistor.
     55
     56  Conversely if the pull-down resistance is zero, one end of the thermistor is
     57  connected to ground and we get the thermistor under the pull-up resistor
     58  and we take the measure between the pull-up resistor and the thermistor.
     59
     60  We can use both pull-up and pull-down resistors at the same time, and then
     61  the figure illustrates where the voltage will be measured for the "connected
     62  ground" and "connected positive" cases.
     63
     64properties:
     65  $nodename:
     66    pattern: "^thermistor(.*)?$"
     67
     68  compatible:
     69    oneOf:
     70      - const: epcos,b57330v2103
     71      - const: epcos,b57891s0103
     72      - const: murata,ncp15wb473
     73      - const: murata,ncp18wb473
     74      - const: murata,ncp21wb473
     75      - const: murata,ncp03wb473
     76      - const: murata,ncp15wl333
     77      - const: murata,ncp03wf104
     78      - const: murata,ncp15xh103
     79      - const: samsung,1404-001221
     80      # Deprecated "ntp," compatible strings
     81      - const: ntc,ncp15wb473
     82        deprecated: true
     83      - const: ntc,ncp18wb473
     84        deprecated: true
     85      - const: ntc,ncp21wb473
     86        deprecated: true
     87      - const: ntc,ncp03wb473
     88        deprecated: true
     89      - const: ntc,ncp15wl333
     90        deprecated: true
     91
     92  "#thermal-sensor-cells":
     93    description: Thermal sensor cells if used for thermal sensoring.
     94    const: 0
     95
     96  pullup-uv:
     97    $ref: /schemas/types.yaml#/definitions/uint32
     98    description: Pull-up voltage in micro volts. Must always be specified.
     99
    100  pullup-ohm:
    101    $ref: /schemas/types.yaml#/definitions/uint32
    102    description: Pull-up resistance in ohms. Must always be specified, even
    103      if zero.
    104
    105  pulldown-ohm:
    106    $ref: /schemas/types.yaml#/definitions/uint32
    107    description: Pull-down resistance in ohms. Must always be specified, even
    108      if zero.
    109
    110  connected-positive:
    111    $ref: /schemas/types.yaml#/definitions/flag
    112    description: Indicates how the thermistor is connected in series with
    113      a pull-up and/or a pull-down resistor. See the description above for
    114      an illustration. If this flag is NOT specified, the thermistor is assumed
    115      to be connected-ground, which usually means a pull-down resistance of
    116      zero but complex arrangements are possible.
    117
    118  # See /schemas/iio/adc/adc.yaml
    119  io-channels:
    120    maxItems: 1
    121    description: IIO ADC channel to read the voltage over the resistor. Must
    122      always be specified.
    123
    124required:
    125  - compatible
    126  - pullup-uv
    127  - pullup-ohm
    128  - pulldown-ohm
    129  - io-channels
    130
    131additionalProperties: false
    132
    133examples:
    134  - |
    135    thermistor0 {
    136      compatible = "murata,ncp18wb473";
    137      io-channels = <&gpadc 0x06>;
    138      pullup-uv = <1800000>;
    139      pullup-ohm = <220000>;
    140      pulldown-ohm = <0>;
    141      #thermal-sensor-cells = <0>;
    142    };