1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/hwmon/adi,ltc2947.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: Analog Devices LTC2947 high precision power and energy monitor
8
9maintainers:
10  - Nuno Sá <nuno.sa@analog.com>
11
12description: |
13  Analog Devices LTC2947 high precision power and energy monitor over SPI or I2C.
14
15  https://www.analog.com/media/en/technical-documentation/data-sheets/LTC2947.pdf
16
17properties:
18  compatible:
19    enum:
20      - adi,ltc2947
21
22  reg:
23    maxItems: 1
24
25  clocks:
26    description:
27      The LTC2947 uses either a trimmed internal oscillator or an external clock
28      as the time base for determining the integration period to represent time,
29      charge and energy. When an external clock is used, this property must be
30      set accordingly.
31    maxItems: 1
32
33  adi,accumulator-ctl-pol:
34    description:
35      This property controls the polarity of current that is accumulated to
36      calculate charge and energy so that, they can be only accumulated for
37      positive current for example. Since there are two sets of registers for
38      the accumulated values, this entry can also have two items which sets
39      energy1/charge1 and energy2/charger2 respectively. Check table 12 of the
40      datasheet for more information on the supported options.
41    allOf:
42      - $ref: /schemas/types.yaml#/definitions/uint32-array
43      - minItems: 2
44        maxItems: 2
45        items:
46          enum: [0, 1, 2, 3]
47          default: 0
48
49  adi,accumulation-deadband-microamp:
50    description:
51      This property controls the Accumulation Dead band which allows to set the
52      level of current below which no accumulation takes place.
53    allOf:
54      - $ref: /schemas/types.yaml#/definitions/uint32
55    maximum: 255
56    default: 0
57
58  adi,gpio-out-pol:
59    description:
60      This property controls the GPIO polarity. Setting it to one makes the GPIO
61      active high, setting it to zero makets it active low. When this property
62      is present, the GPIO is automatically configured as output and set to
63      control a fan as a function of measured temperature.
64    allOf:
65      - $ref: /schemas/types.yaml#/definitions/uint32
66    enum: [0, 1]
67    default: 0
68
69  adi,gpio-in-accum:
70    description:
71      When set, this property sets the GPIO as input. It is then used to control
72      the accumulation of charge, energy and time. This function can be
73      enabled/configured separately for each of the two sets of accumulation
74      registers. Check table 13 of the datasheet for more information on the
75      supported options. This property cannot be used together with
76      adi,gpio-out-pol.
77    allOf:
78      - $ref: /schemas/types.yaml#/definitions/uint32-array
79      - minItems: 2
80        maxItems: 2
81        items:
82          enum: [0, 1, 2]
83          default: 0
84
85required:
86  - compatible
87  - reg
88
89
90additionalProperties: false
91
92examples:
93  - |
94    spi {
95           #address-cells = <1>;
96           #size-cells = <0>;
97
98           ltc2947_spi: ltc2947@0 {
99                   compatible = "adi,ltc2947";
100                   reg = <0>;
101                   /* accumulation takes place always for energ1/charge1. */
102                   /* accumulation only on positive current for energy2/charge2. */
103                   adi,accumulator-ctl-pol = <0 1>;
104           };
105    };
106...
107