| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * htu21.c - Support for Measurement-Specialties |
| * htu21 temperature & humidity sensor |
| * and humidity part of MS8607 sensor |
| * |
| * Copyright (c) 2014 Measurement-Specialties |
| * |
| * (7-bit I2C slave address 0x40) |
| * |
| * Datasheet: |
| * http://www.meas-spec.com/downloads/HTU21D.pdf |
| * Datasheet: |
| * http://www.meas-spec.com/downloads/MS8607-02BA01.pdf |
| */ |
| |
| #include <linux/init.h> |
| #include <linux/device.h> |
| #include <linux/kernel.h> |
| #include <linux/stat.h> |
| #include <linux/module.h> |
| #include <linux/iio/iio.h> |
| #include <linux/iio/sysfs.h> |
| |
| #include "../common/ms_sensors/ms_sensors_i2c.h" |
| |
| #define HTU21_RESET 0xFE |
| |
| enum { |
| HTU21, |
| MS8607 |
| }; |
| |
| static const int htu21_samp_freq[4] = { 20, 40, 70, 120 }; |
| /* String copy of the above const for readability purpose */ |
| static const char htu21_show_samp_freq[] = "20 40 70 120"; |
| |
| static int htu21_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *channel, int *val, |
| int *val2, long mask) |
| { |
| int ret, temperature; |
| unsigned int humidity; |
| struct ms_ht_dev *dev_data = iio_priv(indio_dev); |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_PROCESSED: |
| switch (channel->type) { |
| case IIO_TEMP: /* in milli °C */ |
| ret = ms_sensors_ht_read_temperature(dev_data, |
| &temperature); |
| if (ret) |
| return ret; |
| *val = temperature; |
| |
| return IIO_VAL_INT; |
| case IIO_HUMIDITYRELATIVE: /* in milli %RH */ |
| ret = ms_sensors_ht_read_humidity(dev_data, |
| &humidity); |
| if (ret) |
| return ret; |
| *val = humidity; |
| |
| return IIO_VAL_INT; |
| default: |
| return -EINVAL; |
| } |
| case IIO_CHAN_INFO_SAMP_FREQ: |
| *val = htu21_samp_freq[dev_data->res_index]; |
| |
| return IIO_VAL_INT; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static int htu21_write_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int val, int val2, long mask) |
| { |
| struct ms_ht_dev *dev_data = iio_priv(indio_dev); |
| int i, ret; |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_SAMP_FREQ: |
| i = ARRAY_SIZE(htu21_samp_freq); |
| while (i-- > 0) |
| if (val == htu21_samp_freq[i]) |
| break; |
| if (i < 0) |
| return -EINVAL; |
| mutex_lock(&dev_data->lock); |
| dev_data->res_index = i; |
| ret = ms_sensors_write_resolution(dev_data, i); |
| mutex_unlock(&dev_data->lock); |
| |
| return ret; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static const struct iio_chan_spec htu21_channels[] = { |
| { |
| .type = IIO_TEMP, |
| .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED), |
| .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), |
| }, |
| { |
| .type = IIO_HUMIDITYRELATIVE, |
| .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED), |
| .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), |
| } |
| }; |
| |
| /* |
| * Meas Spec recommendation is to not read temperature |
| * on this driver part for MS8607 |
| */ |
| static const struct iio_chan_spec ms8607_channels[] = { |
| { |
| .type = IIO_HUMIDITYRELATIVE, |
| .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_PROCESSED), |
| .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), |
| } |
| }; |
| |
| static ssize_t htu21_show_battery_low(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
| struct ms_ht_dev *dev_data = iio_priv(indio_dev); |
| |
| return ms_sensors_show_battery_low(dev_data, buf); |
| } |
| |
| static ssize_t htu21_show_heater(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
| struct ms_ht_dev *dev_data = iio_priv(indio_dev); |
| |
| return ms_sensors_show_heater(dev_data, buf); |
| } |
| |
| static ssize_t htu21_write_heater(struct device *dev, |
| struct device_attribute *attr, |
| const char *buf, size_t len) |
| { |
| struct iio_dev *indio_dev = dev_to_iio_dev(dev); |
| struct ms_ht_dev *dev_data = iio_priv(indio_dev); |
| |
| return ms_sensors_write_heater(dev_data, buf, len); |
| } |
| |
| static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(htu21_show_samp_freq); |
| static IIO_DEVICE_ATTR(battery_low, S_IRUGO, |
| htu21_show_battery_low, NULL, 0); |
| static IIO_DEVICE_ATTR(heater_enable, S_IRUGO | S_IWUSR, |
| htu21_show_heater, htu21_write_heater, 0); |
| |
| static struct attribute *htu21_attributes[] = { |
| &iio_const_attr_sampling_frequency_available.dev_attr.attr, |
| &iio_dev_attr_battery_low.dev_attr.attr, |
| &iio_dev_attr_heater_enable.dev_attr.attr, |
| NULL, |
| }; |
| |
| static const struct attribute_group htu21_attribute_group = { |
| .attrs = htu21_attributes, |
| }; |
| |
| static const struct iio_info htu21_info = { |
| .read_raw = htu21_read_raw, |
| .write_raw = htu21_write_raw, |
| .attrs = &htu21_attribute_group, |
| }; |
| |
| static int htu21_probe(struct i2c_client *client, |
| const struct i2c_device_id *id) |
| { |
| struct ms_ht_dev *dev_data; |
| struct iio_dev *indio_dev; |
| int ret; |
| u64 serial_number; |
| |
| if (!i2c_check_functionality(client->adapter, |
| I2C_FUNC_SMBUS_WRITE_BYTE_DATA | |
| I2C_FUNC_SMBUS_WRITE_BYTE | |
| I2C_FUNC_SMBUS_READ_I2C_BLOCK)) { |
| dev_err(&client->dev, |
| "Adapter does not support some i2c transaction\n"); |
| return -EOPNOTSUPP; |
| } |
| |
| indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*dev_data)); |
| if (!indio_dev) |
| return -ENOMEM; |
| |
| dev_data = iio_priv(indio_dev); |
| dev_data->client = client; |
| dev_data->res_index = 0; |
| mutex_init(&dev_data->lock); |
| |
| indio_dev->info = &htu21_info; |
| indio_dev->name = id->name; |
| indio_dev->dev.parent = &client->dev; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| |
| if (id->driver_data == MS8607) { |
| indio_dev->channels = ms8607_channels; |
| indio_dev->num_channels = ARRAY_SIZE(ms8607_channels); |
| } else { |
| indio_dev->channels = htu21_channels; |
| indio_dev->num_channels = ARRAY_SIZE(htu21_channels); |
| } |
| |
| i2c_set_clientdata(client, indio_dev); |
| |
| ret = ms_sensors_reset(client, HTU21_RESET, 15000); |
| if (ret) |
| return ret; |
| |
| ret = ms_sensors_read_serial(client, &serial_number); |
| if (ret) |
| return ret; |
| dev_info(&client->dev, "Serial number : %llx", serial_number); |
| |
| return devm_iio_device_register(&client->dev, indio_dev); |
| } |
| |
| static const struct i2c_device_id htu21_id[] = { |
| {"htu21", HTU21}, |
| {"ms8607-humidity", MS8607}, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(i2c, htu21_id); |
| |
| static const struct of_device_id htu21_of_match[] = { |
| { .compatible = "meas,htu21", }, |
| { .compatible = "meas,ms8607-humidity", }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, htu21_of_match); |
| |
| static struct i2c_driver htu21_driver = { |
| .probe = htu21_probe, |
| .id_table = htu21_id, |
| .driver = { |
| .name = "htu21", |
| .of_match_table = of_match_ptr(htu21_of_match), |
| }, |
| }; |
| |
| module_i2c_driver(htu21_driver); |
| |
| MODULE_DESCRIPTION("Measurement-Specialties htu21 temperature and humidity driver"); |
| MODULE_AUTHOR("William Markezana <william.markezana@meas-spec.com>"); |
| MODULE_AUTHOR("Ludovic Tancerel <ludovic.tancerel@maplehightech.com>"); |
| MODULE_LICENSE("GPL v2"); |