1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-C 1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2 %YAML 1.2 2 %YAML 1.2
3 --- 3 ---
4 $id: http://devicetree.org/schemas/iio/adc/env 4 $id: http://devicetree.org/schemas/iio/adc/envelope-detector.yaml#
5 $schema: http://devicetree.org/meta-schemas/co 5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6 6
7 title: ADC envelope detector using a DAC and a 7 title: ADC envelope detector using a DAC and a comparator
8 8
9 maintainers: 9 maintainers:
10 - Peter Rosin <peda@axentia.se> 10 - Peter Rosin <peda@axentia.se>
11 11
12 description: | 12 description: |
13 The DAC is used to find the peak level of an 13 The DAC is used to find the peak level of an alternating voltage input
14 signal by a binary search using the output o 14 signal by a binary search using the output of a comparator wired to
15 an interrupt pin. Like so: 15 an interrupt pin. Like so:
16 _ 16 _
17 | \ 17 | \
18 input +------>-------|+ \ 18 input +------>-------|+ \
19 | \ 19 | \
20 .-------. | }---. 20 .-------. | }---.
21 | | | / | 21 | | | / |
22 | dac|-->--|- / | 22 | dac|-->--|- / |
23 | | |_/ | 23 | | |_/ |
24 | | | 24 | | |
25 | | | 25 | | |
26 | irq|------<-------' 26 | irq|------<-------'
27 | | 27 | |
28 '-------' 28 '-------'
29 29
30 properties: 30 properties:
31 compatible: 31 compatible:
32 const: axentia,tse850-envelope-detector 32 const: axentia,tse850-envelope-detector
33 33
34 io-channels: 34 io-channels:
35 maxItems: 1 35 maxItems: 1
36 description: Channel node of the dac to be 36 description: Channel node of the dac to be used for comparator input.
37 37
38 io-channel-names: 38 io-channel-names:
39 const: dac 39 const: dac
40 40
41 interrupts: 41 interrupts:
42 maxItems: 1 42 maxItems: 1
43 43
44 interrupt-names: 44 interrupt-names:
45 const: comp 45 const: comp
46 46
47 required: 47 required:
48 - compatible 48 - compatible
49 - io-channels 49 - io-channels
50 - io-channel-names 50 - io-channel-names
51 - interrupts 51 - interrupts
52 - interrupt-names 52 - interrupt-names
53 53
54 additionalProperties: false 54 additionalProperties: false
55 55
56 examples: 56 examples:
57 - | 57 - |
58 #include <dt-bindings/interrupt-controller 58 #include <dt-bindings/interrupt-controller/irq.h>
59 i2c { 59 i2c {
60 #address-cells = <1>; 60 #address-cells = <1>;
61 #size-cells = <0>; 61 #size-cells = <0>;
62 dpot: dpot@28 { 62 dpot: dpot@28 {
63 compatible = "microchip,mcp4651-10 63 compatible = "microchip,mcp4651-104";
64 reg = <0x28>; 64 reg = <0x28>;
65 #io-channel-cells = <1>; 65 #io-channel-cells = <1>;
66 }; 66 };
67 }; 67 };
68 68
69 dac: dac { 69 dac: dac {
70 compatible = "dpot-dac"; 70 compatible = "dpot-dac";
71 vref-supply = <®_3v3>; 71 vref-supply = <®_3v3>;
72 io-channels = <&dpot 0>; 72 io-channels = <&dpot 0>;
73 io-channel-names = "dpot"; 73 io-channel-names = "dpot";
74 #io-channel-cells = <1>; 74 #io-channel-cells = <1>;
75 }; 75 };
76 76
77 envelope-detector { 77 envelope-detector {
78 compatible = "axentia,tse850-envelope- 78 compatible = "axentia,tse850-envelope-detector";
79 io-channels = <&dac 0>; 79 io-channels = <&dac 0>;
80 io-channel-names = "dac"; 80 io-channel-names = "dac";
81 81
82 interrupt-parent = <&gpio>; 82 interrupt-parent = <&gpio>;
83 interrupts = <3 IRQ_TYPE_EDGE_FALLING> 83 interrupts = <3 IRQ_TYPE_EDGE_FALLING>;
84 interrupt-names = "comp"; 84 interrupt-names = "comp";
85 }; 85 };
86 ... 86 ...
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.