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 24 static 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 31 static 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 46 static 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 61 static 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 86 static 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 } 111 112 static int ms5611_i2c_remove(struct i2c_client *client) 113 { 114 return ms5611_remove(i2c_get_clientdata(client)); 115 } 116 117 #if defined(CONFIG_OF) 118 static const struct of_device_id ms5611_i2c_matches[] = { 119 { .compatible = "meas,ms5611" }, 120 { .compatible = "ms5611" }, 121 { .compatible = "meas,ms5607" }, 122 { .compatible = "ms5607" }, 123 { } 124 }; 125 MODULE_DEVICE_TABLE(of, ms5611_i2c_matches); 126 #endif 127 128 static const struct i2c_device_id ms5611_id[] = { 129 { "ms5611", MS5611 }, 130 { "ms5607", MS5607 }, 131 { } 132 }; 133 MODULE_DEVICE_TABLE(i2c, ms5611_id); 134 135 static 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 }; 144 module_i2c_driver(ms5611_driver); 145 146 MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>"); 147 MODULE_DESCRIPTION("MS5611 i2c driver"); 148 MODULE_LICENSE("GPL v2"); 149