| Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 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-latch.yaml# |
| 5 | $schema: http://devicetree.org/meta-schemas/core.yaml# |
| 6 | |
| 7 | title: GPIO latch controller |
| 8 | |
| 9 | maintainers: |
| 10 | - Sascha Hauer <s.hauer@pengutronix.de> |
| 11 | |
| 12 | description: | |
| 13 | This binding describes a GPIO multiplexer based on latches connected to |
| 14 | other GPIOs, like this: |
| 15 | |
| 16 | CLK0 ----------------------. ,--------. |
| 17 | CLK1 -------------------. `--------|> #0 | |
| 18 | | | | |
| 19 | OUT0 ----------------+--|-----------|D0 Q0|-----|< |
| 20 | OUT1 --------------+-|--|-----------|D1 Q1|-----|< |
| 21 | OUT2 ------------+-|-|--|-----------|D2 Q2|-----|< |
| 22 | OUT3 ----------+-|-|-|--|-----------|D3 Q3|-----|< |
| 23 | OUT4 --------+-|-|-|-|--|-----------|D4 Q4|-----|< |
| 24 | OUT5 ------+-|-|-|-|-|--|-----------|D5 Q5|-----|< |
| 25 | OUT6 ----+-|-|-|-|-|-|--|-----------|D6 Q6|-----|< |
| 26 | OUT7 --+-|-|-|-|-|-|-|--|-----------|D7 Q7|-----|< |
| 27 | | | | | | | | | | `--------' |
| 28 | | | | | | | | | | |
| 29 | | | | | | | | | | ,--------. |
| 30 | | | | | | | | | `-----------|> #1 | |
| 31 | | | | | | | | | | | |
| 32 | | | | | | | | `--------------|D0 Q0|-----|< |
| 33 | | | | | | | `----------------|D1 Q1|-----|< |
| 34 | | | | | | `------------------|D2 Q2|-----|< |
| 35 | | | | | `--------------------|D3 Q3|-----|< |
| 36 | | | | `----------------------|D4 Q4|-----|< |
| 37 | | | `------------------------|D5 Q5|-----|< |
| 38 | | `--------------------------|D6 Q6|-----|< |
| 39 | `----------------------------|D7 Q7|-----|< |
| 40 | `--------' |
| 41 | |
| 42 | The number of clk-gpios and latched-gpios is not fixed. The actual number |
| 43 | of number of latches and the number of inputs per latch is derived from |
| 44 | the number of GPIOs given in the corresponding device tree properties. |
| 45 | |
| 46 | properties: |
| 47 | compatible: |
| 48 | const: gpio-latch |
| 49 | "#gpio-cells": |
| 50 | const: 2 |
| 51 | |
| 52 | clk-gpios: |
| 53 | description: Array of GPIOs to be used to clock a latch |
| 54 | |
| 55 | latched-gpios: |
| 56 | description: Array of GPIOs to be used as inputs per latch |
| 57 | |
| 58 | setup-duration-ns: |
| 59 | description: Delay in nanoseconds to wait after the latch inputs have been |
| 60 | set up |
| 61 | |
| 62 | clock-duration-ns: |
| 63 | description: Delay in nanoseconds to wait between clock output changes |
| 64 | |
| 65 | gpio-controller: true |
| 66 | |
| 67 | gpio-line-names: true |
| 68 | |
| 69 | required: |
| 70 | - compatible |
| 71 | - "#gpio-cells" |
| 72 | - gpio-controller |
| 73 | - clk-gpios |
| 74 | - latched-gpios |
| 75 | |
| 76 | additionalProperties: false |
| 77 | |
| 78 | examples: |
| 79 | - | |
| 80 | gpio-latch { |
| 81 | #gpio-cells = <2>; |
| 82 | pinctrl-names = "default"; |
| 83 | pinctrl-0 = <&pinctrl_di_do_leds>; |
| 84 | compatible = "gpio-latch"; |
| 85 | gpio-controller; |
| 86 | setup-duration-ns = <100>; |
| 87 | clock-duration-ns = <100>; |
| 88 | |
| 89 | clk-gpios = <&gpio3 7 0>, <&gpio3 8 0>; |
| 90 | latched-gpios = <&gpio3 21 0>, <&gpio3 22 0>, |
| 91 | <&gpio3 23 0>, <&gpio3 24 0>, |
| 92 | <&gpio3 25 0>, <&gpio3 26 0>, |
| 93 | <&gpio3 27 0>, <&gpio3 28 0>; |
| 94 | }; |