1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
|
// SPDX-License-Identifier: GPL-2.0
/*
* MS5611 pressure and temperature sensor driver (SPI bus)
*
* Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
*
*/
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/spi/spi.h>
#include <linux/mod_devicetable.h>
#include <asm/unaligned.h>
#include "ms5611.h"
static int ms5611_spi_reset(struct ms5611_state *st)
{
u8 cmd = MS5611_RESET;
return spi_write_then_read(st->client, &cmd, 1, NULL, 0);
}
static int ms5611_spi_read_prom_word(struct ms5611_state *st, int index,
u16 *word)
{
int ret;
ret = spi_w8r16be(st->client, MS5611_READ_PROM_WORD + (index << 1));
if (ret < 0)
return ret;
*word = ret;
return 0;
}
static int ms5611_spi_read_adc(struct ms5611_state *st, s32 *val)
{
int ret;
u8 buf[3] = { MS5611_READ_ADC };
ret = spi_write_then_read(st->client, buf, 1, buf, 3);
if (ret < 0)
return ret;
*val = get_unaligned_be24(&buf[0]);
return 0;
}
static int ms5611_spi_read_adc_temp_and_pressure(struct ms5611_state *st,
s32 *temp, s32 *pressure)
{
int ret;
const struct ms5611_osr *osr = st->temp_osr;
/*
* Warning: &osr->cmd MUST be aligned on a word boundary since used as
* 2nd argument (void*) of spi_write_then_read.
*/
ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
if (ret < 0)
return ret;
usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
ret = ms5611_spi_read_adc(st, temp);
if (ret < 0)
return ret;
osr = st->pressure_osr;
ret = spi_write_then_read(st->client, &osr->cmd, 1, NULL, 0);
if (ret < 0)
return ret;
usleep_range(osr->conv_usec, osr->conv_usec + (osr->conv_usec / 10UL));
return ms5611_spi_read_adc(st, pressure);
}
static int ms5611_spi_probe(struct spi_device *spi)
{
int ret;
struct ms5611_state *st;
struct iio_dev *indio_dev;
indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
if (!indio_dev)
return -ENOMEM;
spi_set_drvdata(spi, indio_dev);
spi->mode = SPI_MODE_0;
spi->max_speed_hz = min(spi->max_speed_hz, 20000000U);
spi->bits_per_word = 8;
ret = spi_setup(spi);
if (ret < 0)
return ret;
st = iio_priv(indio_dev);
st->reset = ms5611_spi_reset;
st->read_prom_word = ms5611_spi_read_prom_word;
st->read_adc_temp_and_pressure = ms5611_spi_read_adc_temp_and_pressure;
st->client = spi;
return ms5611_probe(indio_dev, &spi->dev, spi_get_device_id(spi)->name,
spi_get_device_id(spi)->driver_data);
}
static const struct of_device_id ms5611_spi_matches[] = {
{ .compatible = "meas,ms5611" },
{ .compatible = "meas,ms5607" },
{ }
};
MODULE_DEVICE_TABLE(of, ms5611_spi_matches);
static const struct spi_device_id ms5611_id[] = {
{ "ms5611", MS5611 },
{ "ms5607", MS5607 },
{ }
};
MODULE_DEVICE_TABLE(spi, ms5611_id);
static struct spi_driver ms5611_driver = {
.driver = {
.name = "ms5611",
.of_match_table = ms5611_spi_matches
},
.id_table = ms5611_id,
.probe = ms5611_spi_probe,
};
module_spi_driver(ms5611_driver);
MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
MODULE_DESCRIPTION("MS5611 spi driver");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS(IIO_MS5611);
|
