blob: aaa0c4ba91a7c9f14fda64b91d26df91e367d1ab [file] [log] [blame]
Tomasz Duszynskic0644162015-03-14 21:29:31 +01001/*
2 * MS5611 pressure and temperature sensor driver (SPI 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 */
11
12#include <linux/delay.h>
13#include <linux/module.h>
14#include <linux/spi/spi.h>
15
16#include "ms5611.h"
17
18static int ms5611_spi_reset(struct device *dev)
19{
20 u8 cmd = MS5611_RESET;
21 struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
22
23 return spi_write_then_read(st->client, &cmd, 1, NULL, 0);
24}
25
26static int ms5611_spi_read_prom_word(struct device *dev, int index, u16 *word)
27{
28 int ret;
29 struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
30
31 ret = spi_w8r16be(st->client, MS5611_READ_PROM_WORD + (index << 1));
32 if (ret < 0)
33 return ret;
34
35 *word = ret;
36
37 return 0;
38}
39
40static int ms5611_spi_read_adc(struct device *dev, s32 *val)
41{
42 int ret;
43 u8 buf[3] = { MS5611_READ_ADC };
44 struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
45
46 ret = spi_write_then_read(st->client, buf, 1, buf, 3);
47 if (ret < 0)
48 return ret;
49
50 *val = (buf[0] << 16) | (buf[1] << 8) | buf[2];
51
52 return 0;
53}
54
55static int ms5611_spi_read_adc_temp_and_pressure(struct device *dev,
56 s32 *temp, s32 *pressure)
57{
58 u8 cmd;
59 int ret;
60 struct ms5611_state *st = iio_priv(dev_to_iio_dev(dev));
61
62 cmd = MS5611_START_TEMP_CONV;
63 ret = spi_write_then_read(st->client, &cmd, 1, NULL, 0);
64 if (ret < 0)
65 return ret;
66
67 usleep_range(MS5611_CONV_TIME_MIN, MS5611_CONV_TIME_MAX);
68
69 ret = ms5611_spi_read_adc(dev, temp);
70 if (ret < 0)
71 return ret;
72
73 cmd = MS5611_START_PRESSURE_CONV;
74 ret = spi_write_then_read(st->client, &cmd, 1, NULL, 0);
75 if (ret < 0)
76 return ret;
77
78 usleep_range(MS5611_CONV_TIME_MIN, MS5611_CONV_TIME_MAX);
79
80 return ms5611_spi_read_adc(dev, pressure);
81}
82
83static int ms5611_spi_probe(struct spi_device *spi)
84{
85 int ret;
86 struct ms5611_state *st;
87 struct iio_dev *indio_dev;
88
89 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
90 if (!indio_dev)
91 return -ENOMEM;
92
93 spi->mode = SPI_MODE_0;
94 spi->max_speed_hz = 20000000;
95 spi->bits_per_word = 8;
96 ret = spi_setup(spi);
97 if (ret < 0)
98 return ret;
99
100 st = iio_priv(indio_dev);
101 st->reset = ms5611_spi_reset;
102 st->read_prom_word = ms5611_spi_read_prom_word;
103 st->read_adc_temp_and_pressure = ms5611_spi_read_adc_temp_and_pressure;
104 st->client = spi;
105
Tomasz Duszynski9690d81a2015-06-23 20:45:48 +0200106 return ms5611_probe(indio_dev, &spi->dev,
107 spi_get_device_id(spi)->driver_data);
Tomasz Duszynskic0644162015-03-14 21:29:31 +0100108}
109
110static const struct spi_device_id ms5611_id[] = {
Tomasz Duszynski9690d81a2015-06-23 20:45:48 +0200111 { "ms5611", MS5611 },
112 { "ms5607", MS5607 },
Tomasz Duszynskic0644162015-03-14 21:29:31 +0100113 { }
114};
115MODULE_DEVICE_TABLE(spi, ms5611_id);
116
117static struct spi_driver ms5611_driver = {
118 .driver = {
119 .name = "ms5611",
Tomasz Duszynskic0644162015-03-14 21:29:31 +0100120 },
121 .id_table = ms5611_id,
122 .probe = ms5611_spi_probe,
123};
124module_spi_driver(ms5611_driver);
125
126MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
127MODULE_DESCRIPTION("MS5611 spi driver");
128MODULE_LICENSE("GPL v2");