Add driver support for HDC2010/2080 series devices and sysfs documentation for their heater element. HDC2010 is an integrated high-accuracy humidity and temperature sensor with very low power consumption. The device includes a resistive heating element. The temperature range is -40C to 125C with 0.2C accuracy. Humidity measurement is 0 to 100% with 2% RH accuracy. Signed-off-by: Eugene Zaikonnikov <ez@xxxxxxxxxxxxx> --- Heater capabilities are kept as IIO_CONST_ATTR for backwards compatibility (subject to further change). Changes since v9: - style and formatting changes after the feedback diff -uprN -X linux-5.3.8/Documentation/dontdiff linux-5.3.8/Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc2010 linux-5.3.8_hdc2010/Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc2010 --- linux-5.3.8/Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc2010 1970-01-01 01:00:00.000000000 +0100 +++ linux-5.3.8_hdc2010/Documentation/ABI/testing/sysfs-bus-iio-humidity-hdc2010 2019-12-02 11:09:25.803326999 +0100 @@ -0,0 +1,9 @@ +What: /sys/bus/iio/devices/iio:deviceX/out_current_heater_raw +What: /sys/bus/iio/devices/iio:deviceX/out_current_heater_raw_available +KernelVersion: 5.3.8 +Contact: linux-iio@xxxxxxxxxxxxxxx +Description: + Controls the heater device within the humidity sensor to get + rid of excess condensation. + + Valid control values are 0 = OFF, and 1 = ON. diff -uprN -X linux-5.3.8/Documentation/dontdiff linux-5.3.8/drivers/iio/humidity/hdc2010.c linux-5.3.8_hdc2010/drivers/iio/humidity/hdc2010.c --- linux-5.3.8/drivers/iio/humidity/hdc2010.c 1970-01-01 01:00:00.000000000 +0100 +++ linux-5.3.8_hdc2010/drivers/iio/humidity/hdc2010.c 2020-08-07 14:59:31.930027709 +0200 @@ -0,0 +1,353 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * hdc2010.c - Support for the TI HDC2010 and HDC2080 + * temperature + relative humidity sensors + * + * Copyright (C) 2020 Norphonic AS + * Author: Eugene Zaikonnikov <ez@xxxxxxxxxxxxx> + * + * Datasheet: https://www.ti.com/product/HDC2010/datasheet + * Datasheet: https://www.ti.com/product/HDC2080/datasheet + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/bitops.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define HDC2010_REG_TEMP_LOW 0x00 +#define HDC2010_REG_TEMP_HIGH 0x01 +#define HDC2010_REG_HUMIDITY_LOW 0x02 +#define HDC2010_REG_HUMIDITY_HIGH 0x03 +#define HDC2010_REG_INTERRUPT_DRDY 0x04 +#define HDC2010_REG_TEMP_MAX 0x05 +#define HDC2010_REG_HUMIDITY_MAX 0x06 +#define HDC2010_REG_INTERRUPT_EN 0x07 +#define HDC2010_REG_TEMP_OFFSET_ADJ 0x08 +#define HDC2010_REG_HUMIDITY_OFFSET_ADJ 0x09 +#define HDC2010_REG_TEMP_THR_L 0x0a +#define HDC2010_REG_TEMP_THR_H 0x0b +#define HDC2010_REG_RH_THR_L 0x0c +#define HDC2010_REG_RH_THR_H 0x0d +#define HDC2010_REG_RESET_DRDY_INT_CONF 0x0e +#define HDC2010_REG_MEASUREMENT_CONF 0x0f + +#define HDC2010_MEAS_CONF GENMASK(2, 1) +#define HDC2010_MEAS_TRIG BIT(0) +#define HDC2010_HEATER_EN BIT(3) +#define HDC2010_AMM GENMASK(6, 4) + +struct hdc2010_data { + struct i2c_client *client; + struct mutex lock; + u8 measurement_config; + u8 interrupt_config; + u8 drdy_config; +}; + +enum hdc2010_addr_groups { + HDC2010_GROUP_TEMP = 0, + HDC2010_GROUP_HUMIDITY, +}; + +struct hdc2010_reg_record { + unsigned long primary; + unsigned long peak; +}; + +static const struct hdc2010_reg_record hdc2010_reg_translation[] = { + [HDC2010_GROUP_TEMP] = { + .primary = HDC2010_REG_TEMP_LOW, + .peak = HDC2010_REG_TEMP_MAX, + }, + [HDC2010_GROUP_HUMIDITY] = { + .primary = HDC2010_REG_HUMIDITY_LOW, + .peak = HDC2010_REG_HUMIDITY_MAX, + }, +}; + +static IIO_CONST_ATTR(out_current_heater_raw_available, "0 1"); + +static struct attribute *hdc2010_attributes[] = { + &iio_const_attr_out_current_heater_raw_available.dev_attr.attr, + NULL +}; + +static const struct attribute_group hdc2010_attribute_group = { + .attrs = hdc2010_attributes, +}; + +static const struct iio_chan_spec hdc2010_channels[] = { + { + .type = IIO_TEMP, + .address = HDC2010_GROUP_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_PEAK) | + BIT(IIO_CHAN_INFO_OFFSET) | + BIT(IIO_CHAN_INFO_SCALE), + }, + { + .type = IIO_HUMIDITYRELATIVE, + .address = HDC2010_GROUP_HUMIDITY, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_PEAK) | + BIT(IIO_CHAN_INFO_SCALE), + }, + { + .type = IIO_CURRENT, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .extend_name = "heater", + .output = 1, + }, +}; + +static int hdc2010_update_drdy_config(struct hdc2010_data *data, + char mask, char val) +{ + u8 tmp = (~mask & data->drdy_config) | val; + int ret; + + ret = i2c_smbus_write_byte_data(data->client, + HDC2010_REG_RESET_DRDY_INT_CONF, tmp); + if (ret) + return ret; + + data->drdy_config = tmp; + + return 0; +} + +static int hdc2010_get_prim_measurement_word(struct hdc2010_data *data, + struct iio_chan_spec const *chan) +{ + struct i2c_client *client = data->client; + s32 ret; + + ret = i2c_smbus_read_word_data(client, + hdc2010_reg_translation[chan->address].primary); + + if (ret < 0) + dev_err(&client->dev, "Could not read sensor measurement word\n"); + + return ret; +} + +static int hdc2010_get_peak_measurement_byte(struct hdc2010_data *data, + struct iio_chan_spec const *chan) +{ + struct i2c_client *client = data->client; + s32 ret; + + ret = i2c_smbus_read_byte_data(client, + hdc2010_reg_translation[chan->address].peak); + + if (ret < 0) + dev_err(&client->dev, "Could not read sensor measurement byte\n"); + + return ret; +} + +static int hdc2010_get_heater_status(struct hdc2010_data *data) +{ + return !!(data->drdy_config & HDC2010_HEATER_EN); +} + +static int hdc2010_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + struct hdc2010_data *data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_RAW: { + int ret; + + if (chan->type == IIO_CURRENT) { + *val = hdc2010_get_heater_status(data); + return IIO_VAL_INT; + } + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + mutex_lock(&data->lock); + ret = hdc2010_get_prim_measurement_word(data, chan); + mutex_unlock(&data->lock); + iio_device_release_direct_mode(indio_dev); + if (ret < 0) + return ret; + *val = ret; + return IIO_VAL_INT; + } + case IIO_CHAN_INFO_PEAK: { + int ret; + + ret = iio_device_claim_direct_mode(indio_dev); + if (ret) + return ret; + mutex_lock(&data->lock); + ret = hdc2010_get_peak_measurement_byte(data, chan); + mutex_unlock(&data->lock); + iio_device_release_direct_mode(indio_dev); + if (ret < 0) + return ret; + /* Scaling up the value so we can use same offset as RAW */ + *val = ret * 256; + return IIO_VAL_INT; + } + case IIO_CHAN_INFO_SCALE: + *val2 = 65536; + if (chan->type == IIO_TEMP) + *val = 165000; + else + *val = 100000; + return IIO_VAL_FRACTIONAL; + case IIO_CHAN_INFO_OFFSET: + *val = -15887; + *val2 = 515151; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static int hdc2010_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct hdc2010_data *data = iio_priv(indio_dev); + int new, ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + if (chan->type != IIO_CURRENT || val2 != 0) + return -EINVAL; + + switch (val) { + case 1: + new = HDC2010_HEATER_EN; + break; + case 0: + new = 0; + break; + default: + return -EINVAL; + } + + mutex_lock(&data->lock); + ret = hdc2010_update_drdy_config(data, HDC2010_HEATER_EN, new); + mutex_unlock(&data->lock); + return ret; + default: + return -EINVAL; + } +} + +static const struct iio_info hdc2010_info = { + .read_raw = hdc2010_read_raw, + .write_raw = hdc2010_write_raw, + .attrs = &hdc2010_attribute_group, +}; + +static int hdc2010_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct iio_dev *indio_dev; + struct hdc2010_data *data; + u8 tmp; + int ret; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_I2C)) + return -EOPNOTSUPP; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + data->client = client; + mutex_init(&data->lock); + + indio_dev->dev.parent = &client->dev; + /* + * As DEVICE ID register does not differentiate between + * HDC2010 and HDC2080, we have the name hardcoded + */ + indio_dev->name = "hdc2010"; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &hdc2010_info; + + indio_dev->channels = hdc2010_channels; + indio_dev->num_channels = ARRAY_SIZE(hdc2010_channels); + + /* Enable Automatic Measurement Mode at 5Hz */ + ret = hdc2010_update_drdy_config(data, HDC2010_AMM, HDC2010_AMM); + if (ret) + return ret; + + /* + * We enable both temp and humidity measurement. + * However the measurement won't start even in AMM until triggered. + */ + tmp = (data->measurement_config & ~HDC2010_MEAS_CONF) | + HDC2010_MEAS_TRIG; + + ret = i2c_smbus_write_byte_data(client, HDC2010_REG_MEASUREMENT_CONF, tmp); + if (ret) { + dev_warn(&client->dev, "Unable to set up measurement\n"); + if (hdc2010_update_drdy_config(data, HDC2010_AMM, 0)) + dev_warn(&client->dev, "Unable to restore default AMM\n"); + return ret; + }; + + data->measurement_config = tmp; + + return iio_device_register(indio_dev); +} + +static int hdc2010_remove(struct i2c_client *client) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct hdc2010_data *data = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + /* Disable Automatic Measurement Mode */ + if (hdc2010_update_drdy_config(data, HDC2010_AMM, 0)) + dev_warn(&client->dev, "Unable to restore default AMM\n"); + + return 0; +} + +static const struct i2c_device_id hdc2010_id[] = { + { "hdc2010" }, + { "hdc2080" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, hdc2010_id); + +static const struct of_device_id hdc2010_dt_ids[] = { + { .compatible = "ti,hdc2010" }, + { .compatible = "ti,hdc2080" }, + { } +}; +MODULE_DEVICE_TABLE(of, hdc2010_dt_ids); + +static struct i2c_driver hdc2010_driver = { + .driver = { + .name = "hdc2010", + .of_match_table = hdc2010_dt_ids, + }, + .probe = hdc2010_probe, + .remove = hdc2010_remove, + .id_table = hdc2010_id, +}; +module_i2c_driver(hdc2010_driver); + +MODULE_AUTHOR("Eugene Zaikonnikov <ez@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("TI HDC2010 humidity and temperature sensor driver"); +MODULE_LICENSE("GPL"); diff -uprN -X linux-5.3.8/Documentation/dontdiff linux-5.3.8/drivers/iio/humidity/Kconfig linux-5.3.8_hdc2010/drivers/iio/humidity/Kconfig --- linux-5.3.8/drivers/iio/humidity/Kconfig 2019-10-29 09:22:48.000000000 +0100 +++ linux-5.3.8_hdc2010/drivers/iio/humidity/Kconfig 2019-11-28 14:31:27.794242693 +0100 @@ -38,6 +38,16 @@ config HDC100X To compile this driver as a module, choose M here: the module will be called hdc100x. +config HDC2010 + tristate "TI HDC2010 relative humidity and temperature sensor" + depends on I2C + help + Say yes here to build support for the Texas Instruments + HDC2010 and HDC2080 relative humidity and temperature sensors. + + To compile this driver as a module, choose M here: the module + will be called hdc2010. + config HID_SENSOR_HUMIDITY tristate "HID Environmental humidity sensor" depends on HID_SENSOR_HUB diff -uprN -X linux-5.3.8/Documentation/dontdiff linux-5.3.8/drivers/iio/humidity/Makefile linux-5.3.8_hdc2010/drivers/iio/humidity/Makefile --- linux-5.3.8/drivers/iio/humidity/Makefile 2019-10-29 09:22:48.000000000 +0100 +++ linux-5.3.8_hdc2010/drivers/iio/humidity/Makefile 2019-11-28 14:30:40.609892061 +0100 @@ -6,6 +6,7 @@ obj-$(CONFIG_AM2315) += am2315.o obj-$(CONFIG_DHT11) += dht11.o obj-$(CONFIG_HDC100X) += hdc100x.o +obj-$(CONFIG_HDC2010) += hdc2010.o obj-$(CONFIG_HID_SENSOR_HUMIDITY) += hid-sensor-humidity.o hts221-y := hts221_core.o \
