zmk/app/module/drivers/kscan/kscan_gpio.h
Peter Johanson 690bc1bb44 refactor: Move drivers into properly module.
* Align our driver module layout to properly match Zephyr conventions,
  allowing proper CMake setup to amend the library for each type of driver.
2023-09-16 11:52:40 -07:00

62 lines
1.9 KiB
C

/*
* Copyright (c) 2022 The ZMK Contributors
*
* SPDX-License-Identifier: MIT
*/
#pragma once
#include <stdbool.h>
#include <stdint.h>
#include <zephyr/device.h>
#include <zephyr/drivers/gpio.h>
#include <zephyr/dt-bindings/gpio/gpio.h>
#include <zephyr/sys/util.h>
struct kscan_gpio {
struct gpio_dt_spec spec;
/** The index of the GPIO in the devicetree *-gpios array. */
size_t index;
};
/** GPIO_DT_SPEC_GET_BY_IDX(), but for a struct kscan_gpio. */
#define KSCAN_GPIO_GET_BY_IDX(node_id, prop, idx) \
((struct kscan_gpio){.spec = GPIO_DT_SPEC_GET_BY_IDX(node_id, prop, idx), .index = idx})
struct kscan_gpio_list {
struct kscan_gpio *gpios;
size_t len;
};
/** Define a kscan_gpio_list from a compile-time GPIO array. */
#define KSCAN_GPIO_LIST(gpio_array) \
((struct kscan_gpio_list){.gpios = gpio_array, .len = ARRAY_SIZE(gpio_array)})
struct kscan_gpio_port_state {
const struct device *port;
gpio_port_value_t value;
};
/**
* Sorts a GPIO list by port so it can be used with kscan_gpio_pin_get().
*/
void kscan_gpio_list_sort_by_port(struct kscan_gpio_list *list);
/**
* Get logical level of an input pin.
*
* This is equivalent to gpio_pin_get() except that, when iterating through the
* pins in a list which is sorted by kscan_gpio_list_sort_by_port(), it only
* performs one read per port instead of one read per pin.
*
* @param gpio The input pin to read.
* @param state An object to track state between reads. Must be zero-initialized before the first
* use.
*
* @retval 1 If pin logical value is 1 / active.
* @retval 0 If pin logical value is 0 / inactive.
* @retval -EIO I/O error when accessing an external GPIO chip.
* @retval -EWOULDBLOCK if operation would block.
*/
int kscan_gpio_pin_get(const struct kscan_gpio *gpio, struct kscan_gpio_port_state *state);