diff options
Diffstat (limited to 'drivers/iio/pressure/ms5611_i2c.c')
| -rw-r--r-- | drivers/iio/pressure/ms5611_i2c.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/iio/pressure/ms5611_i2c.c b/drivers/iio/pressure/ms5611_i2c.c new file mode 100644 index 000000000..cccc40f7d --- /dev/null +++ b/drivers/iio/pressure/ms5611_i2c.c @@ -0,0 +1,140 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * MS5611 pressure and temperature sensor driver (I2C bus) + * + * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com> + * + * 7-bit I2C slave addresses: + * + * 0x77 (CSB pin low) + * 0x76 (CSB pin high) + * + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> + +#include <asm/unaligned.h> + +#include "ms5611.h" + +static int ms5611_i2c_reset(struct ms5611_state *st) +{ + return i2c_smbus_write_byte(st->client, MS5611_RESET); +} + +static int ms5611_i2c_read_prom_word(struct ms5611_state *st, int index, + u16 *word) +{ + int ret; + + ret = i2c_smbus_read_word_swapped(st->client, + MS5611_READ_PROM_WORD + (index << 1)); + if (ret < 0) + return ret; + + *word = ret; + + return 0; +} + +static int ms5611_i2c_read_adc(struct ms5611_state *st, s32 *val) +{ + int ret; + u8 buf[3]; + + ret = i2c_smbus_read_i2c_block_data(st->client, MS5611_READ_ADC, + 3, buf); + if (ret < 0) + return ret; + + *val = get_unaligned_be24(&buf[0]); + + return 0; +} + +static int ms5611_i2c_read_adc_temp_and_pressure(struct ms5611_state *st, + s32 *temp, s32 *pressure) +{ + int ret; + const struct ms5611_osr *osr = st->temp_osr; + + ret = i2c_smbus_write_byte(st->client, osr->cmd); + if (ret < 0) + return ret; + + usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL)); + ret = ms5611_i2c_read_adc(st, temp); + if (ret < 0) + return ret; + + osr = st->pressure_osr; + ret = i2c_smbus_write_byte(st->client, osr->cmd); + if (ret < 0) + return ret; + + usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL)); + return ms5611_i2c_read_adc(st, pressure); +} + +static int ms5611_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct ms5611_state *st; + struct iio_dev *indio_dev; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_WRITE_BYTE | + I2C_FUNC_SMBUS_READ_WORD_DATA | + I2C_FUNC_SMBUS_READ_I2C_BLOCK)) + return -EOPNOTSUPP; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st)); + if (!indio_dev) + return -ENOMEM; + + st = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + st->reset = ms5611_i2c_reset; + st->read_prom_word = ms5611_i2c_read_prom_word; + st->read_adc_temp_and_pressure = ms5611_i2c_read_adc_temp_and_pressure; + st->client = client; + + return ms5611_probe(indio_dev, &client->dev, id->name, id->driver_data); +} + +static int ms5611_i2c_remove(struct i2c_client *client) +{ + return ms5611_remove(i2c_get_clientdata(client)); +} + +static const struct of_device_id ms5611_i2c_matches[] = { + { .compatible = "meas,ms5611" }, + { .compatible = "meas,ms5607" }, + { } +}; +MODULE_DEVICE_TABLE(of, ms5611_i2c_matches); + +static const struct i2c_device_id ms5611_id[] = { + { "ms5611", MS5611 }, + { "ms5607", MS5607 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ms5611_id); + +static struct i2c_driver ms5611_driver = { + .driver = { + .name = "ms5611", + .of_match_table = ms5611_i2c_matches, + }, + .id_table = ms5611_id, + .probe = ms5611_i2c_probe, + .remove = ms5611_i2c_remove, +}; +module_i2c_driver(ms5611_driver); + +MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>"); +MODULE_DESCRIPTION("MS5611 i2c driver"); +MODULE_LICENSE("GPL v2"); |