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    $ref: /schemas/types.yaml#/definitions/uint32-array
42    minItems: 2
43    maxItems: 2
44    items:
45      enum: [0, 1, 2, 3]
46      default: 0
47
48  adi,accumulation-deadband-microamp:
49    description:
50      This property controls the Accumulation Dead band which allows to set the
51      level of current below which no accumulation takes place.
52    $ref: /schemas/types.yaml#/definitions/uint32
53    maximum: 255
54    default: 0
55
56  adi,gpio-out-pol:
57    description:
58      This property controls the GPIO polarity. Setting it to one makes the GPIO
59      active high, setting it to zero makets it active low. When this property
60      is present, the GPIO is automatically configured as output and set to
61      control a fan as a function of measured temperature.
62    $ref: /schemas/types.yaml#/definitions/uint32
63    enum: [0, 1]
64    default: 0
65
66  adi,gpio-in-accum:
67    description:
68      When set, this property sets the GPIO as input. It is then used to control
69      the accumulation of charge, energy and time. This function can be
70      enabled/configured separately for each of the two sets of accumulation
71      registers. Check table 13 of the datasheet for more information on the
72      supported options. This property cannot be used together with
73      adi,gpio-out-pol.
74    $ref: /schemas/types.yaml#/definitions/uint32-array
75    minItems: 2
76    maxItems: 2
77    items:
78      enum: [0, 1, 2]
79      default: 0
80
81required:
82  - compatible
83  - reg
84
85
86additionalProperties: false
87
88examples:
89  - |
90    spi {
91           #address-cells = <1>;
92           #size-cells = <0>;
93
94           ltc2947_spi: ltc2947@0 {
95                   compatible = "adi,ltc2947";
96                   reg = <0>;
97                   /* accumulation takes place always for energ1/charge1. */
98                   /* accumulation only on positive current for energy2/charge2. */
99                   adi,accumulator-ctl-pol = <0 1>;
100           };
101    };
102...
103