1 // SPDX-License-Identifier: GPL-2.0-only
3  * si7020.c - Silicon Labs Si7013/20/21 Relative Humidity and Temp Sensors
63 		if (chan->type == IIO_CURRENT) {  in si7020_read_raw()
64 			*val = data->heater_reg;  in si7020_read_raw()
68 		ret = i2c_smbus_read_word_swapped(data->client,  in si7020_read_raw()
69 						  chan->type == IIO_TEMP ?  in si7020_read_raw()
76 		 * Humidity values can slightly exceed the 0-100%RH  in si7020_read_raw()
79 		if (chan->type == IIO_HUMIDITYRELATIVE)  in si7020_read_raw()
83 		if (chan->type == IIO_TEMP)  in si7020_read_raw()
93 		 * accuracy.  in si7020_read_raw()
94 		 * Relative humidity will be 0.0032959% too high and  in si7020_read_raw()
95 		 * temperature will be 0.00277344 degrees too high.  in si7020_read_raw()
96 		 * This is no big deal because it's within the accuracy of the  in si7020_read_raw()
99 		if (chan->type == IIO_TEMP)  in si7020_read_raw()
100 			*val = -4368; /* = -46.85 * (65536 >> 2) / 175.72 */  in si7020_read_raw()
102 			*val = -786; /* = -6 * (65536 >> 2) / 125 */  in si7020_read_raw()
108 	return -EINVAL;  in si7020_read_raw()
136 	ret = i2c_smbus_write_byte_data(data->client, cmd, new);  in si7020_update_reg()
154 		if (chan->type != IIO_CURRENT || val2 != 0 ||  in si7020_write_raw()
156 			return -EINVAL;  in si7020_write_raw()
158 		scoped_guard(mutex, &data->lock)  in si7020_write_raw()
159 			ret = si7020_update_reg(data, &data->heater_reg,  in si7020_write_raw()
163 		return -EINVAL;  in si7020_write_raw()
172 	if (mask != IIO_CHAN_INFO_RAW || chan->type != IIO_CURRENT)  in si7020_read_available()
173 		return -EINVAL;  in si7020_read_available()
187 	return sysfs_emit(buf, "%d\n", !!(data->user_reg & SI7020_USR_HEATER_EN));  in si7020_show_heater_en()
203 	scoped_guard(mutex, &data->lock)  in si7020_store_heater_en()
204 		ret = si7020_update_reg(data, &data->user_reg, SI7020CMD_USR_WRITE,  in si7020_store_heater_en()
235 	if (!i2c_check_functionality(client->adapter,  in si7020_probe()
238 		return -EOPNOTSUPP;  in si7020_probe()
244 	/* Wait the maximum power-up time after software reset. */  in si7020_probe()
247 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));  in si7020_probe()
249 		return -ENOMEM;  in si7020_probe()
253 	data->client = client;  in si7020_probe()
254 	mutex_init(&data->lock);  in si7020_probe()
256 	indio_dev->name = dev_name(&client->dev);  in si7020_probe()
257 	indio_dev->modes = INDIO_DIRECT_MODE;  in si7020_probe()
258 	indio_dev->info = &si7020_info;  in si7020_probe()
259 	indio_dev->channels = si7020_channels;  in si7020_probe()
260 	indio_dev->num_channels = ARRAY_SIZE(si7020_channels);  in si7020_probe()
263 	data->user_reg = 0x3A;  in si7020_probe()
264 	data->heater_reg = 0x0;  in si7020_probe()
266 	return devm_iio_device_register(&client->dev, indio_dev);  in si7020_probe()