/*
* Copyright (c) 2020 The ZMK Contributors
*
* SPDX-License-Identifier: MIT
*/
#define DT_DRV_COMPAT zmk_kscan_gpio_demux
#include <device.h>
#include <drivers/kscan.h>
#include <drivers/gpio.h>
#include <logging/log.h>
LOG_MODULE_DECLARE(zmk, CONFIG_ZMK_LOG_LEVEL);
#if DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT)
struct kscan_gpio_item_config {
char *label;
gpio_pin_t pin;
gpio_flags_t flags;
};
// Helper macro
#define PWR_TWO(x) (1 << (x))
// Define GPIO cfg
#define _KSCAN_GPIO_ITEM_CFG_INIT(n, prop, idx) \
{ \
.label = DT_INST_GPIO_LABEL_BY_IDX(n, prop, idx), \
.pin = DT_INST_GPIO_PIN_BY_IDX(n, prop, idx), \
.flags = DT_INST_GPIO_FLAGS_BY_IDX(n, prop, idx), \
},
// Define row and col cfg
#define _KSCAN_GPIO_INPUT_CFG_INIT(idx, n) _KSCAN_GPIO_ITEM_CFG_INIT(n, input_gpios, idx)
#define _KSCAN_GPIO_OUTPUT_CFG_INIT(idx, n) _KSCAN_GPIO_ITEM_CFG_INIT(n, output_gpios, idx)
// Check debounce config
#define CHECK_DEBOUNCE_CFG(n, a, b) COND_CODE_0(DT_INST_PROP(n, debounce_period), a, b)
// Define the row and column lengths
#define INST_MATRIX_INPUTS(n) DT_INST_PROP_LEN(n, input_gpios)
#define INST_DEMUX_GPIOS(n) DT_INST_PROP_LEN(n, output_gpios)
#define INST_MATRIX_OUTPUTS(n) PWR_TWO(INST_DEMUX_GPIOS(n))
#define POLL_INTERVAL(n) DT_INST_PROP(n, polling_interval_msec)
#define GPIO_INST_INIT(n) \
struct kscan_gpio_irq_callback_##n { \
struct CHECK_DEBOUNCE_CFG(n, (k_work), (k_delayed_work)) * work; \
struct gpio_callback callback; \
struct device *dev; \
}; \
\
struct kscan_gpio_config_##n { \
struct kscan_gpio_item_config rows[INST_MATRIX_INPUTS(n)]; \
struct kscan_gpio_item_config cols[INST_DEMUX_GPIOS(n)]; \
}; \
\
struct kscan_gpio_data_##n { \
kscan_callback_t callback; \
struct k_timer poll_timer; \
struct CHECK_DEBOUNCE_CFG(n, (k_work), (k_delayed_work)) work; \
bool matrix_state[INST_MATRIX_INPUTS(n)][INST_MATRIX_OUTPUTS(n)]; \
struct device *rows[INST_MATRIX_INPUTS(n)]; \
struct device *cols[INST_MATRIX_OUTPUTS(n)]; \
struct device *dev; \
}; \
/* IO/GPIO SETUP */ \
/* gpio_input_devices are PHYSICAL IO devices */ \
static struct device **kscan_gpio_input_devices_##n(struct device *dev) { \
struct kscan_gpio_data_##n *data = dev->driver_data; \
return data->rows; \
} \
\
static const struct kscan_gpio_item_config *kscan_gpio_input_configs_##n(struct device *dev) { \
const struct kscan_gpio_config_##n *cfg = dev->config_info; \
return cfg->rows; \
} \
\
/* gpio_output_devices are PHYSICAL IO devices */ \
static struct device **kscan_gpio_output_devices_##n(struct device *dev) { \
struct kscan_gpio_data_##n *data = dev->driver_data; \
return data->cols; \
} \
\
static const struct kscan_gpio_item_config *kscan_gpio_output_configs_##n( \
struct device *dev) { \
const struct kscan_gpio_config_##n *cfg = dev->config_info; \
/* If row2col, rows = outputs & cols = inputs */ \
return cfg->cols; \
} \
/* POLLING SETUP */ \
static void kscan_gpio_timer_handler(struct k_timer *timer) { \
struct kscan_gpio_data_##n *data = \
CONTAINER_OF(timer, struct kscan_gpio_data_##n, poll_timer); \
k_work_submit(&data->work.work); \
} \
\
/* Read the state of the input GPIOs */ \
/* This is the core matrix_scan func */ \
static int kscan_gpio_read_##n(struct device *dev) { \
bool submit_follow_up_read = false; \
struct kscan_gpio_data_##n *data = dev->driver_data; \
static bool read_state[INST_MATRIX_INPUTS(n)][INST_MATRIX_OUTPUTS(n)]; \
for (int o = 0; o < INST_MATRIX_OUTPUTS(n); o++) { \
/* Iterate over bits and set GPIOs accordingly */ \
for (u8_t bit = 0; bit < INST_DEMUX_GPIOS(n); bit++) { \
u8_t state = (o & (0b1 << bit)) >> bit; \
struct device *out_dev = kscan_gpio_output_devices_##n(dev)[bit]; \
const struct kscan_gpio_item_config *out_cfg = \
&kscan_gpio_output_configs_##n(dev)[bit]; \
gpio_pin_set(out_dev, out_cfg->pin, state); \
} \
\
for (int i = 0; i < INST_MATRIX_INPUTS(n); i++) { \
/* Get the input device (port) */ \
struct device *in_dev = kscan_gpio_input_devices_##n(dev)[i]; \
/* Get the input device config (pin) */ \
const struct kscan_gpio_item_config *in_cfg = \
&kscan_gpio_input_configs_##n(dev)[i]; \
read_state[i][o] = gpio_pin_get(in_dev, in_cfg->pin) > 0; \
} \
} \
for (int r = 0; r < INST_MATRIX_INPUTS(n); r++) { \
for (int c = 0; c < INST_MATRIX_OUTPUTS(n); c++) { \
bool pressed = read_state[r][c]; \
submit_follow_up_read = (submit_follow_up_read || pressed); \
if (pressed != data->matrix_state[r][c]) { \
LOG_DBG("Sending event at %d,%d state %s", r, c, (pressed ? "on" : "off")); \
data->matrix_state[r][c] = pressed; \
data->callback(dev, r, c, pressed); \
} \
} \
} \
if (submit_follow_up_read) { \
CHECK_DEBOUNCE_CFG(n, ({ k_work_submit(&data->work); }), ({ \
k_delayed_work_cancel(&data->work); \
k_delayed_work_submit(&data->work, K_MSEC(5)); \
})) \
} \
return 0; \
} \
\
static void kscan_gpio_work_handler_##n(struct k_work *work) { \
struct kscan_gpio_data_##n *data = CONTAINER_OF(work, struct kscan_gpio_data_##n, work); \
kscan_gpio_read_##n(data->dev); \
} \
\
static struct kscan_gpio_data_##n kscan_gpio_data_##n = { \
.rows = {[INST_MATRIX_INPUTS(n) - 1] = NULL}, .cols = {[INST_DEMUX_GPIOS(n) - 1] = NULL}}; \
\
/* KSCAN API configure function */ \
static int kscan_gpio_configure_##n(struct device *dev, kscan_callback_t callback) { \
LOG_DBG("KSCAN API configure"); \
struct kscan_gpio_data_##n *data = dev->driver_data; \
if (!callback) { \
return -EINVAL; \
} \
data->callback = callback; \
LOG_DBG("Configured GPIO %d", n); \
return 0; \
}; \
\
/* KSCAN API enable function */ \
static int kscan_gpio_enable_##n(struct device *dev) { \
LOG_DBG("KSCAN API enable"); \
struct kscan_gpio_data_##n *data = dev->driver_data; \
/* TODO: we might want a follow up to hook into the sleep state hooks in Zephyr, */ \
/* and disable this timer when we enter a sleep state */ \
k_timer_start(&data->poll_timer, K_MSEC(POLL_INTERVAL(n)), K_MSEC(POLL_INTERVAL(n))); \
return 0; \
}; \
\
/* KSCAN API disable function */ \
static int kscan_gpio_disable_##n(struct device *dev) { \
LOG_DBG("KSCAN API disable"); \
struct kscan_gpio_data_##n *data = dev->driver_data; \
k_timer_stop(&data->poll_timer); \
return 0; \
}; \
\
/* GPIO init function*/ \
static int kscan_gpio_init_##n(struct device *dev) { \
LOG_DBG("KSCAN GPIO init"); \
struct kscan_gpio_data_##n *data = dev->driver_data; \
int err; \
/* configure input devices*/ \
struct device **input_devices = kscan_gpio_input_devices_##n(dev); \
for (int i = 0; i < INST_MATRIX_INPUTS(n); i++) { \
const struct kscan_gpio_item_config *in_cfg = &kscan_gpio_input_configs_##n(dev)[i]; \
input_devices[i] = device_get_binding(in_cfg->label); \
if (!input_devices[i]) { \
LOG_ERR("Unable to find input GPIO device"); \
return -EINVAL; \
} \
err = gpio_pin_configure(input_devices[i], in_cfg->pin, GPIO_INPUT | in_cfg->flags); \
if (err) { \
LOG_ERR("Unable to configure pin %d on %s for input", in_cfg->pin, in_cfg->label); \
return err; \
} else { \
LOG_DBG("Configured pin %d on %s for input", in_cfg->pin, in_cfg->label); \
} \
if (err) { \
LOG_ERR("Error adding the callback to the column device"); \
return err; \
} \
} \
/* configure output devices*/ \
struct device **output_devices = kscan_gpio_output_devices_##n(dev); \
for (int o = 0; o < INST_DEMUX_GPIOS(n); o++) { \
const struct kscan_gpio_item_config *out_cfg = &kscan_gpio_output_configs_##n(dev)[o]; \
output_devices[o] = device_get_binding(out_cfg->label); \
if (!output_devices[o]) { \
LOG_ERR("Unable to find output GPIO device"); \
return -EINVAL; \
} \
err = gpio_pin_configure(output_devices[o], out_cfg->pin, \
GPIO_OUTPUT_ACTIVE | out_cfg->flags); \
if (err) { \
LOG_ERR("Unable to configure pin %d on %s for output", out_cfg->pin, \
out_cfg->label); \
return err; \
} else { \
LOG_DBG("Configured pin %d on %s for output", out_cfg->pin, out_cfg->label); \
} \
} \
data->dev = dev; \
\
k_timer_init(&data->poll_timer, kscan_gpio_timer_handler, NULL); \
\
(CHECK_DEBOUNCE_CFG(n, (k_work_init), (k_delayed_work_init)))( \
&data->work, kscan_gpio_work_handler_##n); \
return 0; \
} \
\
static const struct kscan_driver_api gpio_driver_api_##n = { \
.config = kscan_gpio_configure_##n, \
.enable_callback = kscan_gpio_enable_##n, \
.disable_callback = kscan_gpio_disable_##n, \
}; \
\
static const struct kscan_gpio_config_##n kscan_gpio_config_##n = { \
.rows = {UTIL_LISTIFY(INST_MATRIX_INPUTS(n), _KSCAN_GPIO_INPUT_CFG_INIT, n)}, \
.cols = {UTIL_LISTIFY(INST_DEMUX_GPIOS(n), _KSCAN_GPIO_OUTPUT_CFG_INIT, n)}, \
}; \
\
DEVICE_AND_API_INIT(kscan_gpio_##n, DT_INST_LABEL(n), kscan_gpio_init_##n, \
&kscan_gpio_data_##n, &kscan_gpio_config_##n, APPLICATION, \
CONFIG_APPLICATION_INIT_PRIORITY, &gpio_driver_api_##n);
DT_INST_FOREACH_STATUS_OKAY(GPIO_INST_INIT)
#endif /* DT_HAS_COMPAT_STATUS_OKAY(DT_DRV_COMPAT) */