1 // SPDX-License-Identifier: GPL-2.0-only
3  * mlx90614.c - Support for Melexis MLX90614 contactless IR temperature sensor
9  * Driver for the Melexis MLX90614 I2C 16-bit IR thermopile sensor
11  * (7-bit I2C slave address 0x5a, 100KHz bus speed only!)
14  * for at least 33ms.  This is achieved with an extra GPIO that can be connected
18  * always has a pull-up so we do not need an extra GPIO to drive it high.  If
37 /* RAM offsets with 16-bit data, MSB first */
44 /* EEPROM offsets with 16-bit data, MSB first */
58 /* Timings (in ms) */
59 #define MLX90614_TIMING_EEPROM 20 /* time for EEPROM write/erase to complete */
60 #define MLX90614_TIMING_WAKEUP 34 /* time to hold SDA low for wake-up */
61 #define MLX90614_TIMING_STARTUP 250 /* time before first data after wake-up */
66 #define MLX90614_CONST_OFFSET_DEC -13657 /* decimal part of the Kelvin offset */
76 	struct gpio_desc *wakeup_gpio; /* NULL to disable sleep/wake-up */
109 	dev_dbg(&client->dev, "Writing 0x%x to address 0x%x", value, command);  in mlx90614_write_word()
112 	ret = i2c_smbus_xfer(client->adapter, client->addr,  in mlx90614_write_word()
113 			     client->flags | I2C_CLIENT_PEC,  in mlx90614_write_word()
122 	ret = i2c_smbus_xfer(client->adapter, client->addr,  in mlx90614_write_word()
123 			     client->flags | I2C_CLIENT_PEC,  in mlx90614_write_word()
148 		return -EINVAL;  in mlx90614_iir_search()
171  * If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
172  * the last wake-up.  This is normally only needed to get a valid temperature
176 static int mlx90614_power_get(struct mlx90614_data *data, bool startup)  in mlx90614_power_get()  argument
180 	if (!data->wakeup_gpio)  in mlx90614_power_get()
183 	pm_runtime_get_sync(&data->client->dev);  in mlx90614_power_get()
185 	if (startup) {  in mlx90614_power_get()
187 		if (time_before(now, data->ready_timestamp) &&  in mlx90614_power_get()
189 				data->ready_timestamp - now)) != 0) {  in mlx90614_power_get()
190 			pm_runtime_put_autosuspend(&data->client->dev);  in mlx90614_power_get()
191 			return -EINTR;  in mlx90614_power_get()
200 	if (!data->wakeup_gpio)  in mlx90614_power_put()
203 	pm_runtime_mark_last_busy(&data->client->dev);  in mlx90614_power_put()
204 	pm_runtime_put_autosuspend(&data->client->dev);  in mlx90614_power_put()
207 static inline int mlx90614_power_get(struct mlx90614_data *data, bool startup)  in mlx90614_power_get()  argument
227 		switch (channel->channel2) {  in mlx90614_read_raw()
232 			switch (channel->channel) {  in mlx90614_read_raw()
240 				return -EINVAL;  in mlx90614_read_raw()
244 			return -EINVAL;  in mlx90614_read_raw()
250 		ret = i2c_smbus_read_word_data(data->client, cmd);  in mlx90614_read_raw()
258 			return -EIO;  in mlx90614_read_raw()
271 		mutex_lock(&data->lock);  in mlx90614_read_raw()
272 		ret = i2c_smbus_read_word_data(data->client,  in mlx90614_read_raw()
274 		mutex_unlock(&data->lock);  in mlx90614_read_raw()
291 		mutex_lock(&data->lock);  in mlx90614_read_raw()
292 		ret = i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);  in mlx90614_read_raw()
293 		mutex_unlock(&data->lock);  in mlx90614_read_raw()
304 		return -EINVAL;  in mlx90614_read_raw()
318 			return -EINVAL;  in mlx90614_write_raw()
323 		mutex_lock(&data->lock);  in mlx90614_write_raw()
324 		ret = mlx90614_write_word(data->client, MLX90614_EMISSIVITY,  in mlx90614_write_raw()
326 		mutex_unlock(&data->lock);  in mlx90614_write_raw()
332 			return -EINVAL;  in mlx90614_write_raw()
335 		mutex_lock(&data->lock);  in mlx90614_write_raw()
336 		ret = mlx90614_iir_search(data->client,  in mlx90614_write_raw()
338 		mutex_unlock(&data->lock);  in mlx90614_write_raw()
343 		return -EINVAL;  in mlx90614_write_raw()
357 		return -EINVAL;  in mlx90614_write_raw_get_fmt()
406 	if (!data->wakeup_gpio) {  in mlx90614_sleep()
407 		dev_dbg(&data->client->dev, "Sleep disabled");  in mlx90614_sleep()
408 		return -ENOSYS;  in mlx90614_sleep()
411 	dev_dbg(&data->client->dev, "Requesting sleep");  in mlx90614_sleep()
413 	mutex_lock(&data->lock);  in mlx90614_sleep()
414 	ret = i2c_smbus_xfer(data->client->adapter, data->client->addr,  in mlx90614_sleep()
415 			     data->client->flags | I2C_CLIENT_PEC,  in mlx90614_sleep()
418 	mutex_unlock(&data->lock);  in mlx90614_sleep()
425 	if (!data->wakeup_gpio) {  in mlx90614_wakeup()
426 		dev_dbg(&data->client->dev, "Wake-up disabled");  in mlx90614_wakeup()
427 		return -ENOSYS;  in mlx90614_wakeup()
430 	dev_dbg(&data->client->dev, "Requesting wake-up");  in mlx90614_wakeup()
432 	i2c_lock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);  in mlx90614_wakeup()
433 	gpiod_direction_output(data->wakeup_gpio, 0);  in mlx90614_wakeup()
435 	gpiod_direction_input(data->wakeup_gpio);  in mlx90614_wakeup()
436 	i2c_unlock_bus(data->client->adapter, I2C_LOCK_ROOT_ADAPTER);  in mlx90614_wakeup()
438 	data->ready_timestamp = jiffies +  in mlx90614_wakeup()
443 	 * wake-up signal has been sent.  As a workaround, do a dummy read.  in mlx90614_wakeup()
447 	i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);  in mlx90614_wakeup()
452 /* Return wake-up GPIO or NULL if sleep functionality should be disabled. */
457 	if (!i2c_check_functionality(client->adapter,  in mlx90614_probe_wakeup()
459 		dev_info(&client->dev,  in mlx90614_probe_wakeup()
464 	gpio = devm_gpiod_get_optional(&client->dev, "wakeup", GPIOD_IN);  in mlx90614_probe_wakeup()
467 		dev_warn(&client->dev,  in mlx90614_probe_wakeup()
472 		dev_info(&client->dev,  in mlx90614_probe_wakeup()
473 			 "wakeup-gpio not found, sleep disabled");  in mlx90614_probe_wakeup()
481 	return -ENOSYS;  in mlx90614_sleep()
485 	return -ENOSYS;  in mlx90614_wakeup()
513 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))  in mlx90614_probe()
514 		return -EOPNOTSUPP;  in mlx90614_probe()
516 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));  in mlx90614_probe()
518 		return -ENOMEM;  in mlx90614_probe()
522 	data->client = client;  in mlx90614_probe()
523 	mutex_init(&data->lock);  in mlx90614_probe()
524 	data->wakeup_gpio = mlx90614_probe_wakeup(client);  in mlx90614_probe()
528 	indio_dev->name = id->name;  in mlx90614_probe()
529 	indio_dev->modes = INDIO_DIRECT_MODE;  in mlx90614_probe()
530 	indio_dev->info = &mlx90614_info;  in mlx90614_probe()
535 		dev_dbg(&client->dev, "Found single sensor");  in mlx90614_probe()
536 		indio_dev->channels = mlx90614_channels;  in mlx90614_probe()
537 		indio_dev->num_channels = 2;  in mlx90614_probe()
540 		dev_dbg(&client->dev, "Found dual sensor");  in mlx90614_probe()
541 		indio_dev->channels = mlx90614_channels;  in mlx90614_probe()
542 		indio_dev->num_channels = 3;  in mlx90614_probe()
548 	if (data->wakeup_gpio) {  in mlx90614_probe()
549 		pm_runtime_set_autosuspend_delay(&client->dev,  in mlx90614_probe()
551 		pm_runtime_use_autosuspend(&client->dev);  in mlx90614_probe()
552 		pm_runtime_set_active(&client->dev);  in mlx90614_probe()
553 		pm_runtime_enable(&client->dev);  in mlx90614_probe()
566 	if (data->wakeup_gpio) {  in mlx90614_remove()
567 		pm_runtime_disable(&client->dev);  in mlx90614_remove()
568 		if (!pm_runtime_status_suspended(&client->dev))  in mlx90614_remove()
570 		pm_runtime_set_suspended(&client->dev);  in mlx90614_remove()
594 	if (data->wakeup_gpio && pm_runtime_active(dev))  in mlx90614_pm_suspend()
606 	if (data->wakeup_gpio) {  in mlx90614_pm_resume()
657 MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");