1 // SPDX-License-Identifier: GPL-2.0+
3  * cc2.c - Support for the Amphenol ChipCap 2 relative humidity, temperature sensor
11  * https://www.amphenol-sensors.com/en/telaire/humidity/527-humidity-sensors/3095-chipcap-2
59 /* ensure clean off -> on transitions */
98 /* %RH as a per cent mille from a register value */
103 	return tmp / ((1 << 14) - 1);  in cc2_rh_convert()
109 	return data * ((1 << 14) - 1) / CC2_RH_MAX;  in cc2_rh_to_reg()
115 	unsigned long tmp = ((data >> 2) * 165 * 1000U) / ((1 << 14) - 1);  in cc2_temp_convert()
117 	return tmp - 40 * 1000U;  in cc2_temp_convert()
125 	if (regulator_is_enabled(data->regulator))  in cc2_enable()
129 	try_wait_for_completion(&data->complete);  in cc2_enable()
131 	ret = regulator_enable(data->regulator);  in cc2_enable()
137 	data->process_irqs = true;  in cc2_enable()
147 	data->process_irqs = false;  in cc2_disable()
150 	if (regulator_is_enabled(data->regulator)) {  in cc2_disable()
151 		err = regulator_disable(data->regulator);  in cc2_disable()
153 			dev_dbg(&data->client->dev, "Failed to disable device");  in cc2_disable()
163 		return -ETIMEDOUT;  in cc2_cmd_response_diagnostic()
171 		return -EBUSY;  in cc2_cmd_response_diagnostic()
181 		return -ENODATA;  in cc2_cmd_response_diagnostic()
184 		return -EINVAL;  in cc2_cmd_response_diagnostic()
195 		ret = ret < 0 ? ret : -EIO;  in cc2_read_command_status()
199 	return cc2_cmd_response_diagnostic(&client->dev, status);  in cc2_read_command_status()
204  * first 10 ms after power-up. Only in case the command window is missed,
217 		ret = i2c_smbus_write_word_data(data->client, CC2_START_CM, 0);  in cc2_command_mode_start()
221 		if (data->irq_ready > 0) {  in cc2_command_mode_start()
223 			ret = wait_for_completion_timeout(&data->complete,  in cc2_command_mode_start()
226 				return -ETIMEDOUT;  in cc2_command_mode_start()
231 		ret = cc2_read_command_status(data->client);  in cc2_command_mode_start()
232 		if (ret != -ETIMEDOUT || i == CC2_CM_RETRIES)  in cc2_command_mode_start()
250 	ret = i2c_smbus_write_word_data(data->client, CC2_START_NOM, 0);  in cc2_command_mode_finish()
267 	ret = i2c_smbus_write_word_data(data->client, reg, val);  in cc2_write_reg()
271 	if (data->irq_ready > 0) {  in cc2_write_reg()
273 		ret = wait_for_completion_timeout(&data->complete, timeout);  in cc2_write_reg()
275 			ret = -ETIMEDOUT;  in cc2_write_reg()
282 	ret = cc2_read_command_status(data->client);  in cc2_write_reg()
300 	ret = i2c_smbus_write_word_data(data->client, reg, 0);  in cc2_read_reg()
304 	if (data->irq_ready > 0) {  in cc2_read_reg()
306 		ret = wait_for_completion_timeout(&data->complete, timeout);  in cc2_read_reg()
308 			return -ETIMEDOUT;  in cc2_read_reg()
313 	ret = i2c_master_recv(data->client, buf, CC2_EEPROM_DATA_LEN);  in cc2_read_reg()
315 		return ret < 0 ? ret : -EIO;  in cc2_read_reg()
319 	return cc2_read_command_status(data->client);  in cc2_read_reg()
345 		ret = ret < 0 ? ret : -EIO;  in cc2_data_fetch()
350 		return -EBUSY;  in cc2_data_fetch()
353 		return -EIO;  in cc2_data_fetch()
363 		return -EINVAL;  in cc2_data_fetch()
375 	if (data->irq_ready > 0) {  in cc2_read_measurement()
377 		ret = wait_for_completion_timeout(&data->complete, timeout);  in cc2_read_measurement()
379 			return -ETIMEDOUT;  in cc2_read_measurement()
385 	ret = cc2_data_fetch(data->client, type, val);  in cc2_read_measurement()
415  * exiting the command mode, there is no need to force two power-up sequences.
454 			return cc2->rh_alarm.low_alarm_visible ? 0444 : 0;  in cc2_is_visible()
456 			return cc2->rh_alarm.high_alarm_visible ? 0444 : 0;  in cc2_is_visible()
459 			return cc2->rh_alarm.low_alarm_visible ? 0644 : 0;  in cc2_is_visible()
462 			return cc2->rh_alarm.high_alarm_visible ? 0644 : 0;  in cc2_is_visible()
484 	if (cc2->process_irqs)  in cc2_ready_interrupt()
485 		complete(&cc2->complete);  in cc2_ready_interrupt()
494 	if (cc2->process_irqs) {  in cc2_low_interrupt()
495 		hwmon_notify_event(cc2->hwmon, hwmon_humidity,  in cc2_low_interrupt()
497 		cc2->rh_alarm.low_alarm = true;  in cc2_low_interrupt()
507 	if (cc2->process_irqs) {  in cc2_high_interrupt()
508 		hwmon_notify_event(cc2->hwmon, hwmon_humidity,  in cc2_high_interrupt()
510 		cc2->rh_alarm.high_alarm = true;  in cc2_high_interrupt()
526 	if (data->rh_alarm.low_alarm) {  in cc2_humidity_min_alarm_status()
528 		data->rh_alarm.low_alarm = *val;  in cc2_humidity_min_alarm_status()
546 	if (data->rh_alarm.high_alarm) {  in cc2_humidity_max_alarm_status()
548 		data->rh_alarm.high_alarm = *val;  in cc2_humidity_max_alarm_status()
561 	guard(mutex)(&data->dev_access_lock);  in cc2_read()
583 			return -EOPNOTSUPP;  in cc2_read()
586 		return -EOPNOTSUPP;  in cc2_read()
598 		return -EOPNOTSUPP;  in cc2_write()
601 		return -EINVAL;  in cc2_write()
603 	guard(mutex)(&data->dev_access_lock);  in cc2_write()
623 		return -EOPNOTSUPP;  in cc2_write()
631 	data->irq_ready = fwnode_irq_get_byname(dev_fwnode(dev), "ready");  in cc2_request_ready_irq()
632 	if (data->irq_ready > 0) {  in cc2_request_ready_irq()
633 		init_completion(&data->complete);  in cc2_request_ready_irq()
634 		ret = devm_request_threaded_irq(dev, data->irq_ready, NULL,  in cc2_request_ready_irq()
648 	data->irq_low = fwnode_irq_get_byname(dev_fwnode(dev), "low");  in cc2_request_alarm_irqs()
649 	if (data->irq_low > 0) {  in cc2_request_alarm_irqs()
650 		ret = devm_request_threaded_irq(dev, data->irq_low, NULL,  in cc2_request_alarm_irqs()
658 		data->rh_alarm.low_alarm_visible = true;  in cc2_request_alarm_irqs()
661 	data->irq_high = fwnode_irq_get_byname(dev_fwnode(dev), "high");  in cc2_request_alarm_irqs()
662 	if (data->irq_high > 0) {  in cc2_request_alarm_irqs()
663 		ret = devm_request_threaded_irq(dev, data->irq_high, NULL,  in cc2_request_alarm_irqs()
671 		data->rh_alarm.high_alarm_visible = true;  in cc2_request_alarm_irqs()
699 	struct device *dev = &client->dev;  in cc2_probe()
702 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))  in cc2_probe()
703 		return -EOPNOTSUPP;  in cc2_probe()
707 		return -ENOMEM;  in cc2_probe()
711 	mutex_init(&data->dev_access_lock);  in cc2_probe()
713 	data->client = client;  in cc2_probe()
715 	data->regulator = devm_regulator_get_exclusive(dev, "vdd");  in cc2_probe()
716 	if (IS_ERR(data->regulator))  in cc2_probe()
717 		return dev_err_probe(dev, PTR_ERR(data->regulator),  in cc2_probe()
728 	data->hwmon = devm_hwmon_device_register_with_info(dev, client->name,  in cc2_probe()
731 	if (IS_ERR(data->hwmon))  in cc2_probe()
732 		return dev_err_probe(dev, PTR_ERR(data->hwmon),  in cc2_probe()