4  * SPDX-License-Identifier: Apache-2.0
10  * @brief 1-Wire Bus Master driver using Zephyr GPIO interface.
12  * This file contains the implementation of the 1-Wire Bus Master driver using
13  * the Zephyr GPIO interface. The driver is based on GPIO bit-banging and
14  * follows the timing specifications for 1-Wire communication.
21  * - w1_zephyr_serial.c: drivers/w1/w1_zephyr_serial.c
22  * - Analog Devices 1-Wire Communication Through Software:
23  * https://www.analog.com/en/resources/technical-articles/1wire-communication-through-software.html
26 #include <zephyr/drivers/gpio.h>
96 	/** GPIO device used for 1-Wire communication */
103 	/** timing parameters for 1-Wire communication */
137 	const struct w1_gpio_config *cfg = dev->config;  in w1_gpio_reset_bus()
138 	const struct w1_gpio_data *data = dev->data;  in w1_gpio_reset_bus()
140 	const struct gpio_dt_spec *spec = &cfg->spec;  in w1_gpio_reset_bus()
141 	const struct w1_gpio_timing *timing = data->timing;  in w1_gpio_reset_bus()
146 	W1_GPIO_WAIT_US(timing->g);  in w1_gpio_reset_bus()
149 		goto out;  in w1_gpio_reset_bus()
152 	W1_GPIO_WAIT_US(timing->h);  in w1_gpio_reset_bus()
155 		goto out;  in w1_gpio_reset_bus()
158 	W1_GPIO_WAIT_US(timing->i);  in w1_gpio_reset_bus()
161 		goto out;  in w1_gpio_reset_bus()
165 	W1_GPIO_WAIT_US(timing->j);  in w1_gpio_reset_bus()
166 out:  in w1_gpio_reset_bus()
173 	const struct w1_gpio_config *cfg = dev->config;  in w1_gpio_read_bit()
174 	const struct w1_gpio_data *data = dev->data;  in w1_gpio_read_bit()
176 	const struct gpio_dt_spec *spec = &cfg->spec;  in w1_gpio_read_bit()
177 	const struct w1_gpio_timing *timing = data->timing;  in w1_gpio_read_bit()
184 		goto out;  in w1_gpio_read_bit()
187 	W1_GPIO_WAIT_US(timing->a);  in w1_gpio_read_bit()
190 		goto out;  in w1_gpio_read_bit()
193 	W1_GPIO_WAIT_US(timing->e);  in w1_gpio_read_bit()
196 		goto out;  in w1_gpio_read_bit()
200 	W1_GPIO_WAIT_US(timing->f);  in w1_gpio_read_bit()
201 out:  in w1_gpio_read_bit()
208 	const struct w1_gpio_config *cfg = dev->config;  in w1_gpio_write_bit()
209 	const struct w1_gpio_data *data = dev->data;  in w1_gpio_write_bit()
211 	const struct gpio_dt_spec *spec = &cfg->spec;  in w1_gpio_write_bit()
212 	const struct w1_gpio_timing *timing = data->timing;  in w1_gpio_write_bit()
219 		goto out;  in w1_gpio_write_bit()
222 	W1_GPIO_WAIT_US(bit ? timing->a : timing->c);  in w1_gpio_write_bit()
225 		goto out;  in w1_gpio_write_bit()
228 	W1_GPIO_WAIT_US(bit ? timing->b : timing->d);  in w1_gpio_write_bit()
229 out:  in w1_gpio_write_bit()
272 	struct w1_gpio_data *data = dev->data;  in w1_gpio_configure()
276 		data->overdrive_active = (value != 0);  in w1_gpio_configure()
277 		data->timing = data->overdrive_active ? &od : &std;  in w1_gpio_configure()
280 		return -ENOTSUP;  in w1_gpio_configure()
286 	const struct w1_gpio_config *cfg = dev->config;  in w1_gpio_init()
287 	const struct gpio_dt_spec *spec = &cfg->spec;  in w1_gpio_init()
288 	struct w1_gpio_data *data = dev->data;  in w1_gpio_init()
294 			LOG_ERR("Failed to configure GPIO port %s pin %d", spec->port->name,  in w1_gpio_init()
295 				spec->pin);  in w1_gpio_init()
299 		LOG_ERR("GPIO port %s is not ready", spec->port->name);  in w1_gpio_init()
300 		return -ENODEV;  in w1_gpio_init()
303 	data->timing = &std;  in w1_gpio_init()
304 	data->overdrive_active = false;  in w1_gpio_init()
306 	LOG_DBG("w1-gpio initialized, with %d slave devices", cfg->master_config.slave_count);  in w1_gpio_init()