1 // SPDX-License-Identifier: GPL-2.0 2 /* 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 <asm/unaligned.h> 20 21 #include "ms5611.h" 22 23 static int ms5611_i2c_reset(struct ms5611_state *st) 24 { 25 return i2c_smbus_write_byte(st->client, MS5611_RESET); 26 } 27 28 static 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 43 static 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 58 static 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 82 static 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 } 107 108 static const struct of_device_id ms5611_i2c_matches[] = { 109 { .compatible = "meas,ms5611" }, 110 { .compatible = "meas,ms5607" }, 111 { } 112 }; 113 MODULE_DEVICE_TABLE(of, ms5611_i2c_matches); 114 115 static const struct i2c_device_id ms5611_id[] = { 116 { "ms5611", MS5611 }, 117 { "ms5607", MS5607 }, 118 { } 119 }; 120 MODULE_DEVICE_TABLE(i2c, ms5611_id); 121 122 static 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_new = ms5611_i2c_probe, 129 }; 130 module_i2c_driver(ms5611_driver); 131 132 MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>"); 133 MODULE_DESCRIPTION("MS5611 i2c driver"); 134 MODULE_LICENSE("GPL v2"); 135 MODULE_IMPORT_NS(IIO_MS5611); 136