xref: /linux/Documentation/devicetree/bindings/iio/resolver/adi,ad2s1210.yaml (revision e7d759f31ca295d589f7420719c311870bb3166f) 
1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/iio/resolver/adi,ad2s1210.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: Analog Devices AD2S1210 Resolver-to-Digital Converter
8
9maintainers:
10  - Michael Hennerich <michael.hennerich@analog.com>
11
12description: |
13  The AD2S1210 is a complete 10-bit to 16-bit resolution tracking
14  resolver-to-digital converter, integrating an on-board programmable
15  sinusoidal oscillator that provides sine wave excitation for
16  resolvers.
17
18  The AD2S1210 allows the user to read the angular position or the
19  angular velocity data directly from the parallel outputs or through
20  the serial interface.
21
22  The mode of operation of the communication channel (parallel or serial) is
23  selected by the A0 and A1 input pins. In normal mode, data is latched by
24  toggling the SAMPLE line and can then be read directly. In configuration mode,
25  data is read or written using a register access scheme (address byte with
26  read/write flag and data byte).
27
28    A1  A0  Result
29     0   0  Normal mode - position output
30     0   1  Normal mode - velocity output
31     1   0  Reserved
32     1   1  Configuration mode
33
34  In normal mode, the resolution of the digital output is selected using
35  the RES0 and RES1 input pins. In configuration mode, the resolution is
36  selected by setting the RES0 and RES1 bits in the control register.
37
38  RES1  RES0  Resolution (Bits)
39     0     0  10
40     0     1  12
41     1     0  14
42     1     1  16
43
44  Note on SPI connections: The CS line on the AD2S1210 should hard-wired to
45  logic low and the WR/FSYNC line on the AD2S1210 should be connected to the
46  SPI CSn output of the SPI controller.
47
48  Datasheet:
49  https://www.analog.com/media/en/technical-documentation/data-sheets/ad2s1210.pdf
50
51properties:
52  compatible:
53    const: adi,ad2s1210
54
55  reg:
56    maxItems: 1
57
58  spi-max-frequency:
59    maximum: 25000000
60
61  spi-cpha: true
62
63  avdd-supply:
64    description:
65      A 4.75 to 5.25 V regulator that powers the Analog Supply Voltage (AVDD)
66      pin.
67
68  dvdd-supply:
69    description:
70      A 4.75 to 5.25 V regulator that powers the Digital Supply Voltage (DVDD)
71      pin.
72
73  vdrive-supply:
74    description:
75      A 2.3 to 5.25 V regulator that powers the Logic Power Supply Input
76      (VDrive) pin.
77
78  clocks:
79    maxItems: 1
80    description: External oscillator clock (CLKIN).
81
82  reset-gpios:
83    description:
84      GPIO connected to the /RESET pin. As the line needs to be low for the
85      reset to be active, it should be configured as GPIO_ACTIVE_LOW.
86    maxItems: 1
87
88  sample-gpios:
89    description:
90      GPIO connected to the /SAMPLE pin. As the line needs to be low to trigger
91      a sample, it should be configured as GPIO_ACTIVE_LOW.
92    maxItems: 1
93
94  mode-gpios:
95    description:
96      GPIO lines connected to the A0 and A1 pins. These pins select the data
97      transfer mode.
98    minItems: 2
99    maxItems: 2
100
101  resolution-gpios:
102    description:
103      GPIO lines connected to the RES0 and RES1 pins. These pins select the
104      resolution of the digital output. If omitted, it is assumed that the
105      RES0 and RES1 pins are hard-wired to match the assigned-resolution-bits
106      property.
107    minItems: 2
108    maxItems: 2
109
110  fault-gpios:
111    description:
112      GPIO lines connected to the LOT and DOS pins. These pins combined indicate
113      the type of fault present, if any. As these pins a pulled low to indicate
114      a fault condition, they should be configured as GPIO_ACTIVE_LOW.
115    minItems: 2
116    maxItems: 2
117
118  adi,fixed-mode:
119    description:
120      This is used to indicate the selected mode if A0 and A1 are hard-wired
121      instead of connected to GPIOS (i.e. mode-gpios is omitted).
122    $ref: /schemas/types.yaml#/definitions/string
123    enum: [config, velocity, position]
124
125  assigned-resolution-bits:
126    description:
127      Resolution of the digital output required by the application. This
128      determines the precision of the angle and/or the maximum speed that can
129      be measured. If resolution-gpios is omitted, it is assumed that RES0 and
130      RES1 are hard-wired to match this value.
131    enum: [10, 12, 14, 16]
132
133required:
134  - compatible
135  - reg
136  - spi-cpha
137  - avdd-supply
138  - dvdd-supply
139  - vdrive-supply
140  - clocks
141  - sample-gpios
142  - assigned-resolution-bits
143
144oneOf:
145  - required:
146      - mode-gpios
147  - required:
148      - adi,fixed-mode
149
150allOf:
151  - $ref: /schemas/spi/spi-peripheral-props.yaml#
152
153unevaluatedProperties: false
154
155examples:
156  - |
157    #include <dt-bindings/gpio/gpio.h>
158
159    spi {
160        #address-cells = <1>;
161        #size-cells = <0>;
162
163        resolver@0 {
164            compatible = "adi,ad2s1210";
165            reg = <0>;
166            spi-max-frequency = <20000000>;
167            spi-cpha;
168            avdd-supply = <&avdd_regulator>;
169            dvdd-supply = <&dvdd_regulator>;
170            vdrive-supply = <&vdrive_regulator>;
171            clocks = <&ext_osc>;
172            sample-gpios = <&gpio0 90 GPIO_ACTIVE_LOW>;
173            mode-gpios = <&gpio0 86 0>, <&gpio0 87 0>;
174            resolution-gpios = <&gpio0 88 0>, <&gpio0 89 0>;
175            assigned-resolution-bits = <16>;
176        };
177    };
178