LXR linux/drivers/iio/pressure/ms5611

   1/*
   2 * MS5611 pressure and temperature sensor driver (I2C bus)
   3 *
   4 * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 *
  10 * 7-bit I2C slave addresses:
  11 *
  12 * 0x77 (CSB pin low)
  13 * 0x76 (CSB pin high)
  14 *
  15 */
  16
  17#include <linux/delay.h>
  18#include <linux/i2c.h>
  19#include <linux/module.h>
  20#include <linux/of_device.h>
  21
  22#include "ms5611.h"
  23
  24static int ms5611_i2c_reset(struct device *dev)
  25{
  26        struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
  27
  28        return i2c_smbus_write_byte(st->client, MS5611_RESET);
  29}
  30
  31static int ms5611_i2c_read_prom_word(struct device *dev, int index, u16 *word)
  32{
  33        int ret;
  34        struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
  35
  36        ret = i2c_smbus_read_word_swapped(st->client,
  37                        MS5611_READ_PROM_WORD + (index << 1));
  38        if (ret < 0)
  39                return ret;
  40
  41        *word = ret;
  42
  43        return 0;
  44}
  45
  46static int ms5611_i2c_read_adc(struct ms5611_state *st, s32 *val)
  47{
  48        int ret;
  49        u8 buf[3];
  50
  51        ret = i2c_smbus_read_i2c_block_data(st->client, MS5611_READ_ADC,
  52                                            3, buf);
  53        if (ret < 0)
  54                return ret;
  55
  56        *val = (buf[0] << 16) | (buf[1] << 8) | buf[2];
  57
  58        return 0;
  59}
  60
  61static int ms5611_i2c_read_adc_temp_and_pressure(struct device *dev,
  62                                                 s32 *temp, s32 *pressure)
  63{
  64        int ret;
  65        struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
  66        const struct ms5611_osr *osr = st->temp_osr;
  67
  68        ret = i2c_smbus_write_byte(st->client, osr->cmd);
  69        if (ret < 0)
  70                return ret;
  71
  72        usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
  73        ret = ms5611_i2c_read_adc(st, temp);
  74        if (ret < 0)
  75                return ret;
  76
  77        osr = st->pressure_osr;
  78        ret = i2c_smbus_write_byte(st->client, osr->cmd);
  79        if (ret < 0)
  80                return ret;
  81
  82        usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
  83        return ms5611_i2c_read_adc(st, pressure);
  84}
  85
  86static int ms5611_i2c_probe(struct i2c_client *client,
  87                            const struct i2c_device_id *id)
  88{
  89        struct ms5611_state *st;
  90        struct iio_dev *indio_dev;
  91
  92        if (!i2c_check_functionality(client->adapter,
  93                                     I2C_FUNC_SMBUS_WRITE_BYTE |
  94                                     I2C_FUNC_SMBUS_READ_WORD_DATA |
  95                                     I2C_FUNC_SMBUS_READ_I2C_BLOCK))
  96                return -EOPNOTSUPP;
  97
  98        indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
  99        if (!indio_dev)
 100                return -ENOMEM;
 101
 102        st = iio_priv(indio_dev);
 103        i2c_set_clientdata(client, indio_dev);
 104        st->reset = ms5611_i2c_reset;
 105        st->read_prom_word = ms5611_i2c_read_prom_word;
 106        st->read_adc_temp_and_pressure = ms5611_i2c_read_adc_temp_and_pressure;
 107        st->client = client;
 108
 109        return ms5611_probe(indio_dev, &client->dev, id->name, id->driver_data);
 110}
 111
 112static int ms5611_i2c_remove(struct i2c_client *client)
 113{
 114        return ms5611_remove(i2c_get_clientdata(client));
 115}
 116
 117#if defined(CONFIG_OF)
 118static const struct of_device_id ms5611_i2c_matches[] = {
 119        { .compatible = "meas,ms5611" },
 120        { .compatible = "ms5611" },
 121        { .compatible = "meas,ms5607" },
 122        { .compatible = "ms5607" },
 123        { }
 124};
 125MODULE_DEVICE_TABLE(of, ms5611_i2c_matches);
 126#endif
 127
 128static const struct i2c_device_id ms5611_id[] = {
 129        { "ms5611", MS5611 },
 130        { "ms5607", MS5607 },
 131        { }
 132};
 133MODULE_DEVICE_TABLE(i2c, ms5611_id);
 134
 135static struct i2c_driver ms5611_driver = {
 136        .driver = {
 137                .name = "ms5611",
 138                .of_match_table = of_match_ptr(ms5611_i2c_matches)
 139        },
 140        .id_table = ms5611_id,
 141        .probe = ms5611_i2c_probe,
 142        .remove = ms5611_i2c_remove,
 143};
 144module_i2c_driver(ms5611_driver);
 145
 146MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
 147MODULE_DESCRIPTION("MS5611 i2c driver");
 148MODULE_LICENSE("GPL v2");
 149