1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * ADIS16130 Digital Output, High Precision Angular Rate Sensor driver
4 *
5 * Copyright 2010 Analog Devices Inc.
6 */
7
8#include <linux/mutex.h>
9#include <linux/kernel.h>
10#include <linux/spi/spi.h>
11#include <linux/module.h>
12
13#include <linux/iio/iio.h>
14
15#include <asm/unaligned.h>
16
17#define ADIS16130_CON 0x0
18#define ADIS16130_CON_RD (1 << 6)
19#define ADIS16130_IOP 0x1
20
21/* 1 = data-ready signal low when unread data on all channels; */
22#define ADIS16130_IOP_ALL_RDY (1 << 3)
23#define ADIS16130_IOP_SYNC (1 << 0) /* 1 = synchronization enabled */
24#define ADIS16130_RATEDATA 0x8 /* Gyroscope output, rate of rotation */
25#define ADIS16130_TEMPDATA 0xA /* Temperature output */
26#define ADIS16130_RATECS 0x28 /* Gyroscope channel setup */
27#define ADIS16130_RATECS_EN (1 << 3) /* 1 = channel enable; */
28#define ADIS16130_TEMPCS 0x2A /* Temperature channel setup */
29#define ADIS16130_TEMPCS_EN (1 << 3)
30#define ADIS16130_RATECONV 0x30
31#define ADIS16130_TEMPCONV 0x32
32#define ADIS16130_MODE 0x38
33#define ADIS16130_MODE_24BIT (1 << 1) /* 1 = 24-bit resolution; */
34
35/**
36 * struct adis16130_state - device instance specific data
37 * @us: actual spi_device to write data
38 * @buf_lock: mutex to protect tx and rx
39 * @buf: unified tx/rx buffer
40 **/
41struct adis16130_state {
42 struct spi_device *us;
43 struct mutex buf_lock;
44 u8 buf[4] __aligned(IIO_DMA_MINALIGN);
45};
46
47static int adis16130_spi_read(struct iio_dev *indio_dev, u8 reg_addr, u32 *val)
48{
49 int ret;
50 struct adis16130_state *st = iio_priv(indio_dev);
51 struct spi_transfer xfer = {
52 .tx_buf = st->buf,
53 .rx_buf = st->buf,
54 .len = 4,
55 };
56
57 mutex_lock(&st->buf_lock);
58
59 st->buf[0] = ADIS16130_CON_RD | reg_addr;
60 st->buf[1] = st->buf[2] = st->buf[3] = 0;
61
62 ret = spi_sync_transfer(spi: st->us, xfers: &xfer, num_xfers: 1);
63 if (ret == 0)
64 *val = get_unaligned_be24(p: &st->buf[1]);
65 mutex_unlock(lock: &st->buf_lock);
66
67 return ret;
68}
69
70static int adis16130_read_raw(struct iio_dev *indio_dev,
71 struct iio_chan_spec const *chan,
72 int *val, int *val2,
73 long mask)
74{
75 int ret;
76 u32 temp;
77
78 switch (mask) {
79 case IIO_CHAN_INFO_RAW:
80 /* Take the iio_dev status lock */
81 ret = adis16130_spi_read(indio_dev, reg_addr: chan->address, val: &temp);
82 if (ret)
83 return ret;
84 *val = temp;
85 return IIO_VAL_INT;
86 case IIO_CHAN_INFO_SCALE:
87 switch (chan->type) {
88 case IIO_ANGL_VEL:
89 /* 0 degree = 838860, 250 degree = 14260608 */
90 *val = 250;
91 *val2 = 336440817; /* RAD_TO_DEGREE(14260608 - 8388608) */
92 return IIO_VAL_FRACTIONAL;
93 case IIO_TEMP:
94 /* 0C = 8036283, 105C = 9516048 */
95 *val = 105000;
96 *val2 = 9516048 - 8036283;
97 return IIO_VAL_FRACTIONAL;
98 default:
99 return -EINVAL;
100 }
101 case IIO_CHAN_INFO_OFFSET:
102 switch (chan->type) {
103 case IIO_ANGL_VEL:
104 *val = -8388608;
105 return IIO_VAL_INT;
106 case IIO_TEMP:
107 *val = -8036283;
108 return IIO_VAL_INT;
109 default:
110 return -EINVAL;
111 }
112 }
113
114 return -EINVAL;
115}
116
117static const struct iio_chan_spec adis16130_channels[] = {
118 {
119 .type = IIO_ANGL_VEL,
120 .modified = 1,
121 .channel2 = IIO_MOD_Z,
122 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
123 BIT(IIO_CHAN_INFO_SCALE) |
124 BIT(IIO_CHAN_INFO_OFFSET),
125 .address = ADIS16130_RATEDATA,
126 }, {
127 .type = IIO_TEMP,
128 .indexed = 1,
129 .channel = 0,
130 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
131 BIT(IIO_CHAN_INFO_SCALE) |
132 BIT(IIO_CHAN_INFO_OFFSET),
133 .address = ADIS16130_TEMPDATA,
134 }
135};
136
137static const struct iio_info adis16130_info = {
138 .read_raw = &adis16130_read_raw,
139};
140
141static int adis16130_probe(struct spi_device *spi)
142{
143 struct adis16130_state *st;
144 struct iio_dev *indio_dev;
145
146 /* setup the industrialio driver allocated elements */
147 indio_dev = devm_iio_device_alloc(parent: &spi->dev, sizeof_priv: sizeof(*st));
148 if (!indio_dev)
149 return -ENOMEM;
150 st = iio_priv(indio_dev);
151 /* this is only used for removal purposes */
152 spi_set_drvdata(spi, data: indio_dev);
153 st->us = spi;
154 mutex_init(&st->buf_lock);
155 indio_dev->name = spi->dev.driver->name;
156 indio_dev->channels = adis16130_channels;
157 indio_dev->num_channels = ARRAY_SIZE(adis16130_channels);
158 indio_dev->info = &adis16130_info;
159 indio_dev->modes = INDIO_DIRECT_MODE;
160
161 return devm_iio_device_register(&spi->dev, indio_dev);
162}
163
164static struct spi_driver adis16130_driver = {
165 .driver = {
166 .name = "adis16130",
167 },
168 .probe = adis16130_probe,
169};
170module_spi_driver(adis16130_driver);
171
172MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
173MODULE_DESCRIPTION("Analog Devices ADIS16130 High Precision Angular Rate");
174MODULE_LICENSE("GPL v2");
175MODULE_ALIAS("spi:adis16130");
176

source code of linux/drivers/iio/gyro/adis16130.c