summaryrefslogtreecommitdiff
path: root/drivers/iio/gyro/adis16130.c
blob: de3f66f89496c43870d8611ae57501643036048c (plain)
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
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * ADIS16130 Digital Output, High Precision Angular Rate Sensor driver
 *
 * Copyright 2010 Analog Devices Inc.
 */

#include <linux/mutex.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/module.h>

#include <linux/iio/iio.h>

#define ADIS16130_CON         0x0
#define ADIS16130_CON_RD      (1 << 6)
#define ADIS16130_IOP         0x1

/* 1 = data-ready signal low when unread data on all channels; */
#define ADIS16130_IOP_ALL_RDY (1 << 3)
#define ADIS16130_IOP_SYNC    (1 << 0) /* 1 = synchronization enabled */
#define ADIS16130_RATEDATA    0x8 /* Gyroscope output, rate of rotation */
#define ADIS16130_TEMPDATA    0xA /* Temperature output */
#define ADIS16130_RATECS      0x28 /* Gyroscope channel setup */
#define ADIS16130_RATECS_EN   (1 << 3) /* 1 = channel enable; */
#define ADIS16130_TEMPCS      0x2A /* Temperature channel setup */
#define ADIS16130_TEMPCS_EN   (1 << 3)
#define ADIS16130_RATECONV    0x30
#define ADIS16130_TEMPCONV    0x32
#define ADIS16130_MODE        0x38
#define ADIS16130_MODE_24BIT  (1 << 1) /* 1 = 24-bit resolution; */

/**
 * struct adis16130_state - device instance specific data
 * @us:			actual spi_device to write data
 * @buf_lock:		mutex to protect tx and rx
 * @buf:		unified tx/rx buffer
 **/
struct adis16130_state {
	struct spi_device		*us;
	struct mutex			buf_lock;
	u8				buf[4] ____cacheline_aligned;
};

static int adis16130_spi_read(struct iio_dev *indio_dev, u8 reg_addr, u32 *val)
{
	int ret;
	struct adis16130_state *st = iio_priv(indio_dev);
	struct spi_transfer xfer = {
		.tx_buf = st->buf,
		.rx_buf = st->buf,
		.len = 4,
	};

	mutex_lock(&st->buf_lock);

	st->buf[0] = ADIS16130_CON_RD | reg_addr;
	st->buf[1] = st->buf[2] = st->buf[3] = 0;

	ret = spi_sync_transfer(st->us, &xfer, 1);
	if (ret == 0)
		*val = (st->buf[1] << 16) | (st->buf[2] << 8) | st->buf[3];
	mutex_unlock(&st->buf_lock);

	return ret;
}

static int adis16130_read_raw(struct iio_dev *indio_dev,
			      struct iio_chan_spec const *chan,
			      int *val, int *val2,
			      long mask)
{
	int ret;
	u32 temp;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
		/* Take the iio_dev status lock */
		mutex_lock(&indio_dev->mlock);
		ret = adis16130_spi_read(indio_dev, chan->address, &temp);
		mutex_unlock(&indio_dev->mlock);
		if (ret)
			return ret;
		*val = temp;
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		switch (chan->type) {
		case IIO_ANGL_VEL:
			/* 0 degree = 838860, 250 degree = 14260608 */
			*val = 250;
			*val2 = 336440817; /* RAD_TO_DEGREE(14260608 - 8388608) */
			return IIO_VAL_FRACTIONAL;
		case IIO_TEMP:
			/* 0C = 8036283, 105C = 9516048 */
			*val = 105000;
			*val2 = 9516048 - 8036283;
			return IIO_VAL_FRACTIONAL;
		default:
			return -EINVAL;
		}
	case IIO_CHAN_INFO_OFFSET:
		switch (chan->type) {
		case IIO_ANGL_VEL:
			*val = -8388608;
			return IIO_VAL_INT;
		case IIO_TEMP:
			*val = -8036283;
			return IIO_VAL_INT;
		default:
			return -EINVAL;
		}
	}

	return -EINVAL;
}

static const struct iio_chan_spec adis16130_channels[] = {
	{
		.type = IIO_ANGL_VEL,
		.modified = 1,
		.channel2 = IIO_MOD_Z,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
			BIT(IIO_CHAN_INFO_SCALE) |
			BIT(IIO_CHAN_INFO_OFFSET),
		.address = ADIS16130_RATEDATA,
	}, {
		.type = IIO_TEMP,
		.indexed = 1,
		.channel = 0,
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
			BIT(IIO_CHAN_INFO_SCALE) |
			BIT(IIO_CHAN_INFO_OFFSET),
		.address = ADIS16130_TEMPDATA,
	}
};

static const struct iio_info adis16130_info = {
	.read_raw = &adis16130_read_raw,
};

static int adis16130_probe(struct spi_device *spi)
{
	struct adis16130_state *st;
	struct iio_dev *indio_dev;

	/* setup the industrialio driver allocated elements */
	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
	if (!indio_dev)
		return -ENOMEM;
	st = iio_priv(indio_dev);
	/* this is only used for removal purposes */
	spi_set_drvdata(spi, indio_dev);
	st->us = spi;
	mutex_init(&st->buf_lock);
	indio_dev->name = spi->dev.driver->name;
	indio_dev->channels = adis16130_channels;
	indio_dev->num_channels = ARRAY_SIZE(adis16130_channels);
	indio_dev->dev.parent = &spi->dev;
	indio_dev->info = &adis16130_info;
	indio_dev->modes = INDIO_DIRECT_MODE;

	return devm_iio_device_register(&spi->dev, indio_dev);
}

static struct spi_driver adis16130_driver = {
	.driver = {
		.name = "adis16130",
	},
	.probe = adis16130_probe,
};
module_spi_driver(adis16130_driver);

MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
MODULE_DESCRIPTION("Analog Devices ADIS16130 High Precision Angular Rate");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("spi:adis16130");