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1// SPDX-License-Identifier: GPL-2.02/*3 * MS5611 pressure and temperature sensor driver (I2C bus)4 *5 * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>6 *7 * 7-bit I2C slave addresses:8 *9 * 0x77 (CSB pin low)10 * 0x76 (CSB pin high)11 *12 */13 14#include <linux/delay.h>15#include <linux/i2c.h>16#include <linux/module.h>17#include <linux/mod_devicetable.h>18 19#include <linux/unaligned.h>20 21#include "ms5611.h"22 23static int ms5611_i2c_reset(struct ms5611_state *st)24{25 return i2c_smbus_write_byte(st->client, MS5611_RESET);26}27 28static int ms5611_i2c_read_prom_word(struct ms5611_state *st, int index,29 u16 *word)30{31 int ret;32 33 ret = i2c_smbus_read_word_swapped(st->client,34 MS5611_READ_PROM_WORD + (index << 1));35 if (ret < 0)36 return ret;37 38 *word = ret;39 40 return 0;41}42 43static int ms5611_i2c_read_adc(struct ms5611_state *st, s32 *val)44{45 int ret;46 u8 buf[3];47 48 ret = i2c_smbus_read_i2c_block_data(st->client, MS5611_READ_ADC,49 3, buf);50 if (ret < 0)51 return ret;52 53 *val = get_unaligned_be24(&buf[0]);54 55 return 0;56}57 58static int ms5611_i2c_read_adc_temp_and_pressure(struct ms5611_state *st,59 s32 *temp, s32 *pressure)60{61 int ret;62 const struct ms5611_osr *osr = st->temp_osr;63 64 ret = i2c_smbus_write_byte(st->client, osr->cmd);65 if (ret < 0)66 return ret;67 68 usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));69 ret = ms5611_i2c_read_adc(st, temp);70 if (ret < 0)71 return ret;72 73 osr = st->pressure_osr;74 ret = i2c_smbus_write_byte(st->client, osr->cmd);75 if (ret < 0)76 return ret;77 78 usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));79 return ms5611_i2c_read_adc(st, pressure);80}81 82static int ms5611_i2c_probe(struct i2c_client *client)83{84 const struct i2c_device_id *id = i2c_client_get_device_id(client);85 struct ms5611_state *st;86 struct iio_dev *indio_dev;87 88 if (!i2c_check_functionality(client->adapter,89 I2C_FUNC_SMBUS_WRITE_BYTE |90 I2C_FUNC_SMBUS_READ_WORD_DATA |91 I2C_FUNC_SMBUS_READ_I2C_BLOCK))92 return -EOPNOTSUPP;93 94 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));95 if (!indio_dev)96 return -ENOMEM;97 98 st = iio_priv(indio_dev);99 i2c_set_clientdata(client, indio_dev);100 st->reset = ms5611_i2c_reset;101 st->read_prom_word = ms5611_i2c_read_prom_word;102 st->read_adc_temp_and_pressure = ms5611_i2c_read_adc_temp_and_pressure;103 st->client = client;104 105 return ms5611_probe(indio_dev, &client->dev, id->name, id->driver_data);106}107 108static const struct of_device_id ms5611_i2c_matches[] = {109 { .compatible = "meas,ms5611" },110 { .compatible = "meas,ms5607" },111 { }112};113MODULE_DEVICE_TABLE(of, ms5611_i2c_matches);114 115static const struct i2c_device_id ms5611_id[] = {116 { "ms5611", MS5611 },117 { "ms5607", MS5607 },118 { }119};120MODULE_DEVICE_TABLE(i2c, ms5611_id);121 122static struct i2c_driver ms5611_driver = {123 .driver = {124 .name = "ms5611",125 .of_match_table = ms5611_i2c_matches,126 },127 .id_table = ms5611_id,128 .probe = ms5611_i2c_probe,129};130module_i2c_driver(ms5611_driver);131 132MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");133MODULE_DESCRIPTION("MS5611 i2c driver");134MODULE_LICENSE("GPL v2");135MODULE_IMPORT_NS(IIO_MS5611);136