1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 %YAML 1.2
3 ---
4 $id: http://devicetree.org/schemas/gpio/gpio-delay.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6
7 title: GPIO delay controller
8
9 maintainers:
10 - Alexander Stein <linux@ew.tq-group.com>
11
12 description: |
13 This binding describes an electrical setup where setting an GPIO output
14 is delayed by some external setup, e.g. RC circuit.
15
16 +----------+ +-----------+
17 | | VCC_B | |
18 | | | | |
19 | | VCC_A _ | |
20 | GPIO | | | R | Consumer |
21 |controller| ___ |_| | |
22 | | | | | | |
23 | [IOx|-------| |--+-----|-----+ |
24 | | |___| | | input |
25 | | | | |
26 +----------+ --- C +-----------+
27 ---
28 |
29 -
30 GND
31
32 If the input on the consumer is controlled by an open-drain signal
33 attached to an RC circuit the ramp-up delay is not under control
34 of the GPIO controller.
35
36 properties:
37 compatible:
38 const: gpio-delay
39
40 "#gpio-cells":
41 description: |
42 Specifies the pin, ramp-up and ramp-down delays. The
43 delays are specified in microseconds.
44 const: 3
45
46 gpios:
47 description: Array of GPIOs which output signal change is delayed
48 minItems: 1
49 maxItems: 32
50
51 gpio-controller: true
52
53 gpio-line-names:
54 minItems: 1
55 maxItems: 32
56
57 required:
58 - compatible
59 - "#gpio-cells"
60 - gpio-controller
61 - gpios
62
63 additionalProperties: false
64
65 examples:
66 - |
67 #include <dt-bindings/gpio/gpio.h>
68
69 enable_delay: enable-delay {
70 compatible = "gpio-delay";
71 #gpio-cells = <3>;
72 gpio-controller;
73 gpios = <&gpio0 3 GPIO_ACTIVE_LOW>,
74 <&gpio3 1 GPIO_ACTIVE_HIGH>;
75 };
76
77 consumer {
78 enable-gpios = <&enable_delay 0 130000 30000>;
79 };
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.