blob: 233bd0f379c939566543bba860ed90d6eaf68b5a [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Senseair Sunrise 006-0-0007 CO2 sensor driver.
*
* Copyright (C) 2021 Jacopo Mondi
*
* List of features not yet supported by the driver:
* - controllable EN pin
* - single-shot operations using the nDRY pin.
* - ABC/target calibration
*/
#include <linux/bitops.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/regmap.h>
#include <linux/time64.h>
#include <linux/iio/iio.h>
#define DRIVER_NAME "sunrise_co2"
#define SUNRISE_ERROR_STATUS_REG 0x00
#define SUNRISE_CO2_FILTERED_COMP_REG 0x06
#define SUNRISE_CHIP_TEMPERATURE_REG 0x08
#define SUNRISE_CALIBRATION_STATUS_REG 0x81
#define SUNRISE_CALIBRATION_COMMAND_REG 0x82
#define SUNRISE_CALIBRATION_FACTORY_CMD 0x7c02
#define SUNRISE_CALIBRATION_BACKGROUND_CMD 0x7c06
/*
* The calibration timeout is not characterized in the datasheet.
* Use 30 seconds as a reasonable upper limit.
*/
#define SUNRISE_CALIBRATION_TIMEOUT_US (30 * USEC_PER_SEC)
struct sunrise_dev {
struct i2c_client *client;
struct regmap *regmap;
/* Protects access to IIO attributes. */
struct mutex lock;
bool ignore_nak;
};
/* Custom regmap read/write operations: perform unlocked access to the i2c bus. */
static int sunrise_regmap_read(void *context, const void *reg_buf,
size_t reg_size, void *val_buf, size_t val_size)
{
struct i2c_client *client = context;
struct sunrise_dev *sunrise = i2c_get_clientdata(client);
union i2c_smbus_data data;
int ret;
if (reg_size != 1 || !val_size)
return -EINVAL;
memset(&data, 0, sizeof(data));
data.block[0] = val_size;
/*
* Wake up sensor by sending sensor address: START, sensor address,
* STOP. Sensor will not ACK this byte.
*
* The chip enters a low power state after 15ms without
* communications or after a complete read/write sequence.
*/
__i2c_smbus_xfer(client->adapter, client->addr,
sunrise->ignore_nak ? I2C_M_IGNORE_NAK : 0,
I2C_SMBUS_WRITE, 0, I2C_SMBUS_BYTE_DATA, &data);
usleep_range(500, 1500);
ret = __i2c_smbus_xfer(client->adapter, client->addr, client->flags,
I2C_SMBUS_READ, ((u8 *)reg_buf)[0],
I2C_SMBUS_I2C_BLOCK_DATA, &data);
if (ret < 0)
return ret;
memcpy(val_buf, &data.block[1], data.block[0]);
return 0;
}
static int sunrise_regmap_write(void *context, const void *val_buf, size_t count)
{
struct i2c_client *client = context;
struct sunrise_dev *sunrise = i2c_get_clientdata(client);
union i2c_smbus_data data;
/* Discard reg address from values count. */
if (!count)
return -EINVAL;
count--;
memset(&data, 0, sizeof(data));
data.block[0] = count;
memcpy(&data.block[1], (u8 *)val_buf + 1, count);
__i2c_smbus_xfer(client->adapter, client->addr,
sunrise->ignore_nak ? I2C_M_IGNORE_NAK : 0,
I2C_SMBUS_WRITE, 0, I2C_SMBUS_BYTE_DATA, &data);
usleep_range(500, 1500);
return __i2c_smbus_xfer(client->adapter, client->addr, client->flags,
I2C_SMBUS_WRITE, ((u8 *)val_buf)[0],
I2C_SMBUS_I2C_BLOCK_DATA, &data);
}
/*
* Sunrise i2c read/write operations: lock the i2c segment to avoid losing the
* wake up session. Use custom regmap operations that perform unlocked access to
* the i2c bus.
*/
static int sunrise_read_byte(struct sunrise_dev *sunrise, u8 reg)
{
const struct i2c_client *client = sunrise->client;
const struct device *dev = &client->dev;
unsigned int val;
int ret;
i2c_lock_bus(client->adapter, I2C_LOCK_SEGMENT);
ret = regmap_read(sunrise->regmap, reg, &val);
i2c_unlock_bus(client->adapter, I2C_LOCK_SEGMENT);
if (ret) {
dev_err(dev, "Read byte failed: reg 0x%02x (%d)\n", reg, ret);
return ret;
}
return val;
}
static int sunrise_read_word(struct sunrise_dev *sunrise, u8 reg, u16 *val)
{
const struct i2c_client *client = sunrise->client;
const struct device *dev = &client->dev;
__be16 be_val;
int ret;
i2c_lock_bus(client->adapter, I2C_LOCK_SEGMENT);
ret = regmap_bulk_read(sunrise->regmap, reg, &be_val, sizeof(be_val));
i2c_unlock_bus(client->adapter, I2C_LOCK_SEGMENT);
if (ret) {
dev_err(dev, "Read word failed: reg 0x%02x (%d)\n", reg, ret);
return ret;
}
*val = be16_to_cpu(be_val);
return 0;
}
static int sunrise_write_byte(struct sunrise_dev *sunrise, u8 reg, u8 val)
{
const struct i2c_client *client = sunrise->client;
const struct device *dev = &client->dev;
int ret;
i2c_lock_bus(client->adapter, I2C_LOCK_SEGMENT);
ret = regmap_write(sunrise->regmap, reg, val);
i2c_unlock_bus(client->adapter, I2C_LOCK_SEGMENT);
if (ret)
dev_err(dev, "Write byte failed: reg 0x%02x (%d)\n", reg, ret);
return ret;
}
static int sunrise_write_word(struct sunrise_dev *sunrise, u8 reg, u16 data)
{
const struct i2c_client *client = sunrise->client;
const struct device *dev = &client->dev;
__be16 be_data = cpu_to_be16(data);
int ret;
i2c_lock_bus(client->adapter, I2C_LOCK_SEGMENT);
ret = regmap_bulk_write(sunrise->regmap, reg, &be_data, sizeof(be_data));
i2c_unlock_bus(client->adapter, I2C_LOCK_SEGMENT);
if (ret)
dev_err(dev, "Write word failed: reg 0x%02x (%d)\n", reg, ret);
return ret;
}
/* Trigger a calibration cycle. */
enum {
SUNRISE_CALIBRATION_FACTORY,
SUNRISE_CALIBRATION_BACKGROUND,
};
static const struct sunrise_calib_data {
u16 cmd;
u8 bit;
const char * const name;
} calib_data[] = {
[SUNRISE_CALIBRATION_FACTORY] = {
SUNRISE_CALIBRATION_FACTORY_CMD,
BIT(2),
"factory_calibration",
},
[SUNRISE_CALIBRATION_BACKGROUND] = {
SUNRISE_CALIBRATION_BACKGROUND_CMD,
BIT(5),
"background_calibration",
},
};
static int sunrise_calibrate(struct sunrise_dev *sunrise,
const struct sunrise_calib_data *data)
{
unsigned int status;
int ret;
/* Reset the calibration status reg. */
ret = sunrise_write_byte(sunrise, SUNRISE_CALIBRATION_STATUS_REG, 0x00);
if (ret)
return ret;
/* Write a calibration command and poll the calibration status bit. */
ret = sunrise_write_word(sunrise, SUNRISE_CALIBRATION_COMMAND_REG, data->cmd);
if (ret)
return ret;
dev_dbg(&sunrise->client->dev, "%s in progress\n", data->name);
/*
* Calibration takes several seconds, so the sleep time between reads
* can be pretty relaxed.
*/
return read_poll_timeout(sunrise_read_byte, status, status & data->bit,
200000, SUNRISE_CALIBRATION_TIMEOUT_US, false,
sunrise, SUNRISE_CALIBRATION_STATUS_REG);
}
static ssize_t sunrise_cal_factory_write(struct iio_dev *iiodev,
uintptr_t private,
const struct iio_chan_spec *chan,
const char *buf, size_t len)
{
struct sunrise_dev *sunrise = iio_priv(iiodev);
bool enable;
int ret;
ret = kstrtobool(buf, &enable);
if (ret)
return ret;
if (!enable)
return len;
mutex_lock(&sunrise->lock);
ret = sunrise_calibrate(sunrise, &calib_data[SUNRISE_CALIBRATION_FACTORY]);
mutex_unlock(&sunrise->lock);
if (ret)
return ret;
return len;
}
static ssize_t sunrise_cal_background_write(struct iio_dev *iiodev,
uintptr_t private,
const struct iio_chan_spec *chan,
const char *buf, size_t len)
{
struct sunrise_dev *sunrise = iio_priv(iiodev);
bool enable;
int ret;
ret = kstrtobool(buf, &enable);
if (ret)
return ret;
if (!enable)
return len;
mutex_lock(&sunrise->lock);
ret = sunrise_calibrate(sunrise, &calib_data[SUNRISE_CALIBRATION_BACKGROUND]);
mutex_unlock(&sunrise->lock);
if (ret)
return ret;
return len;
}
/* Enumerate and retrieve the chip error status. */
enum {
SUNRISE_ERROR_FATAL,
SUNRISE_ERROR_I2C,
SUNRISE_ERROR_ALGORITHM,
SUNRISE_ERROR_CALIBRATION,
SUNRISE_ERROR_SELF_DIAGNOSTIC,
SUNRISE_ERROR_OUT_OF_RANGE,
SUNRISE_ERROR_MEMORY,
SUNRISE_ERROR_NO_MEASUREMENT,
SUNRISE_ERROR_LOW_VOLTAGE,
SUNRISE_ERROR_MEASUREMENT_TIMEOUT,
};
static const char * const sunrise_error_statuses[] = {
[SUNRISE_ERROR_FATAL] = "error_fatal",
[SUNRISE_ERROR_I2C] = "error_i2c",
[SUNRISE_ERROR_ALGORITHM] = "error_algorithm",
[SUNRISE_ERROR_CALIBRATION] = "error_calibration",
[SUNRISE_ERROR_SELF_DIAGNOSTIC] = "error_self_diagnostic",
[SUNRISE_ERROR_OUT_OF_RANGE] = "error_out_of_range",
[SUNRISE_ERROR_MEMORY] = "error_memory",
[SUNRISE_ERROR_NO_MEASUREMENT] = "error_no_measurement",
[SUNRISE_ERROR_LOW_VOLTAGE] = "error_low_voltage",
[SUNRISE_ERROR_MEASUREMENT_TIMEOUT] = "error_measurement_timeout",
};
static const struct iio_enum sunrise_error_statuses_enum = {
.items = sunrise_error_statuses,
.num_items = ARRAY_SIZE(sunrise_error_statuses),
};
static ssize_t sunrise_error_status_read(struct iio_dev *iiodev,
uintptr_t private,
const struct iio_chan_spec *chan,
char *buf)
{
struct sunrise_dev *sunrise = iio_priv(iiodev);
unsigned long errors;
ssize_t len = 0;
u16 value;
int ret;
u8 i;
mutex_lock(&sunrise->lock);
ret = sunrise_read_word(sunrise, SUNRISE_ERROR_STATUS_REG, &value);
if (ret) {
mutex_unlock(&sunrise->lock);
return ret;
}
errors = value;
for_each_set_bit(i, &errors, ARRAY_SIZE(sunrise_error_statuses))
len += sysfs_emit_at(buf, len, "%s ", sunrise_error_statuses[i]);
if (len)
buf[len - 1] = '\n';
mutex_unlock(&sunrise->lock);
return len;
}
static const struct iio_chan_spec_ext_info sunrise_concentration_ext_info[] = {
/* Calibration triggers. */
{
.name = "calibration_factory",
.write = sunrise_cal_factory_write,
.shared = IIO_SEPARATE,
},
{
.name = "calibration_background",
.write = sunrise_cal_background_write,
.shared = IIO_SEPARATE,
},
/* Error statuses. */
{
.name = "error_status",
.read = sunrise_error_status_read,
.shared = IIO_SHARED_BY_ALL,
},
{
.name = "error_status_available",
.shared = IIO_SHARED_BY_ALL,
.read = iio_enum_available_read,
.private = (uintptr_t)&sunrise_error_statuses_enum,
},
{}
};
static const struct iio_chan_spec sunrise_channels[] = {
{
.type = IIO_CONCENTRATION,
.modified = 1,
.channel2 = IIO_MOD_CO2,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.ext_info = sunrise_concentration_ext_info,
},
{
.type = IIO_TEMP,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
},
};
static int sunrise_read_raw(struct iio_dev *iio_dev,
const struct iio_chan_spec *chan,
int *val, int *val2, long mask)
{
struct sunrise_dev *sunrise = iio_priv(iio_dev);
u16 value;
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_CONCENTRATION:
mutex_lock(&sunrise->lock);
ret = sunrise_read_word(sunrise, SUNRISE_CO2_FILTERED_COMP_REG,
&value);
*val = value;
mutex_unlock(&sunrise->lock);
if (ret)
return ret;
return IIO_VAL_INT;
case IIO_TEMP:
mutex_lock(&sunrise->lock);
ret = sunrise_read_word(sunrise, SUNRISE_CHIP_TEMPERATURE_REG,
&value);
*val = value;
mutex_unlock(&sunrise->lock);
if (ret)
return ret;
return IIO_VAL_INT;
default:
return -EINVAL;
}
case IIO_CHAN_INFO_SCALE:
switch (chan->type) {
case IIO_CONCENTRATION:
/*
* 1 / 10^4 to comply with IIO scale for CO2
* (percentage). The chip CO2 reading range is [400 -
* 5000] ppm which corresponds to [0,004 - 0,5] %.
*/
*val = 1;
*val2 = 10000;
return IIO_VAL_FRACTIONAL;
case IIO_TEMP:
/* x10 to comply with IIO scale (millidegrees celsius). */
*val = 10;
return IIO_VAL_INT;
default:
return -EINVAL;
}
default:
return -EINVAL;
}
}
static const struct iio_info sunrise_info = {
.read_raw = sunrise_read_raw,
};
static const struct regmap_bus sunrise_regmap_bus = {
.read = sunrise_regmap_read,
.write = sunrise_regmap_write,
};
static const struct regmap_config sunrise_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
};
static int sunrise_probe(struct i2c_client *client)
{
struct sunrise_dev *sunrise;
struct iio_dev *iio_dev;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_BLOCK_DATA)) {
dev_err(&client->dev,
"Adapter does not support required functionalities\n");
return -EOPNOTSUPP;
}
iio_dev = devm_iio_device_alloc(&client->dev, sizeof(*sunrise));
if (!iio_dev)
return -ENOMEM;
sunrise = iio_priv(iio_dev);
sunrise->client = client;
mutex_init(&sunrise->lock);
i2c_set_clientdata(client, sunrise);
sunrise->regmap = devm_regmap_init(&client->dev, &sunrise_regmap_bus,
client, &sunrise_regmap_config);
if (IS_ERR(sunrise->regmap)) {
dev_err(&client->dev, "Failed to initialize regmap\n");
return PTR_ERR(sunrise->regmap);
}
/*
* The chip nacks the wake up message. If the adapter does not support
* protocol mangling do not set the I2C_M_IGNORE_NAK flag at the expense
* of possible cruft in the logs.
*/
if (i2c_check_functionality(client->adapter, I2C_FUNC_PROTOCOL_MANGLING))
sunrise->ignore_nak = true;
iio_dev->info = &sunrise_info;
iio_dev->name = DRIVER_NAME;
iio_dev->channels = sunrise_channels;
iio_dev->num_channels = ARRAY_SIZE(sunrise_channels);
iio_dev->modes = INDIO_DIRECT_MODE;
return devm_iio_device_register(&client->dev, iio_dev);
}
static const struct of_device_id sunrise_of_match[] = {
{ .compatible = "senseair,sunrise-006-0-0007" },
{}
};
MODULE_DEVICE_TABLE(of, sunrise_of_match);
static struct i2c_driver sunrise_driver = {
.driver = {
.name = DRIVER_NAME,
.of_match_table = sunrise_of_match,
},
.probe_new = sunrise_probe,
};
module_i2c_driver(sunrise_driver);
MODULE_AUTHOR("Jacopo Mondi <jacopo@jmondi.org>");
MODULE_DESCRIPTION("Senseair Sunrise 006-0-0007 CO2 sensor IIO driver");
MODULE_LICENSE("GPL v2");