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
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
/*
* ADIS16080/100 Yaw Rate Gyroscope with SPI driver
*
* Copyright 2010 Analog Devices Inc.
*
* Licensed under the GPL-2 or later.
*/
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include "../iio.h"
#include "../sysfs.h"
#include "gyro.h"
#include "../adc/adc.h"
#define ADIS16080_DIN_GYRO (0 << 10) /* Gyroscope output */
#define ADIS16080_DIN_TEMP (1 << 10) /* Temperature output */
#define ADIS16080_DIN_AIN1 (2 << 10)
#define ADIS16080_DIN_AIN2 (3 << 10)
/*
* 1: Write contents on DIN to control register.
* 0: No changes to control register.
*/
#define ADIS16080_DIN_WRITE (1 << 15)
/**
* struct adis16080_state - device instance specific data
* @us: actual spi_device to write data
* @indio_dev: industrial I/O device structure
* @buf: transmit or receive buffer
* @buf_lock: mutex to protect tx and rx
**/
struct adis16080_state {
struct spi_device *us;
struct iio_dev *indio_dev;
struct mutex buf_lock;
u8 buf[2] ____cacheline_aligned;
};
static int adis16080_spi_write(struct device *dev,
u16 val)
{
int ret;
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct adis16080_state *st = iio_dev_get_devdata(indio_dev);
mutex_lock(&st->buf_lock);
st->buf[0] = val >> 8;
st->buf[1] = val;
ret = spi_write(st->us, st->buf, 2);
mutex_unlock(&st->buf_lock);
return ret;
}
static int adis16080_spi_read(struct device *dev,
u16 *val)
{
int ret;
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct adis16080_state *st = iio_dev_get_devdata(indio_dev);
mutex_lock(&st->buf_lock);
ret = spi_read(st->us, st->buf, 2);
if (ret == 0)
*val = ((st->buf[0] & 0xF) << 8) | st->buf[1];
mutex_unlock(&st->buf_lock);
return ret;
}
static ssize_t adis16080_read(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
struct iio_dev *indio_dev = dev_get_drvdata(dev);
u16 val = 0;
ssize_t ret;
/* Take the iio_dev status lock */
mutex_lock(&indio_dev->mlock);
ret = adis16080_spi_write(dev,
this_attr->address | ADIS16080_DIN_WRITE);
if (ret < 0)
goto error_ret;
ret = adis16080_spi_read(dev, &val);
error_ret:
mutex_unlock(&indio_dev->mlock);
if (ret == 0)
return sprintf(buf, "%d\n", val);
else
return ret;
}
static IIO_DEV_ATTR_GYRO_Z(adis16080_read, ADIS16080_DIN_GYRO);
static IIO_DEVICE_ATTR(temp_raw, S_IRUGO, adis16080_read, NULL,
ADIS16080_DIN_TEMP);
static IIO_DEV_ATTR_IN_RAW(0, adis16080_read, ADIS16080_DIN_AIN1);
static IIO_DEV_ATTR_IN_RAW(1, adis16080_read, ADIS16080_DIN_AIN2);
static struct attribute *adis16080_attributes[] = {
&iio_dev_attr_gyro_z_raw.dev_attr.attr,
&iio_dev_attr_temp_raw.dev_attr.attr,
&iio_dev_attr_in0_raw.dev_attr.attr,
&iio_dev_attr_in1_raw.dev_attr.attr,
NULL
};
static const struct attribute_group adis16080_attribute_group = {
.attrs = adis16080_attributes,
};
static int __devinit adis16080_probe(struct spi_device *spi)
{
int ret, regdone = 0;
struct adis16080_state *st = kzalloc(sizeof *st, GFP_KERNEL);
if (!st) {
ret = -ENOMEM;
goto error_ret;
}
/* this is only used for removal purposes */
spi_set_drvdata(spi, st);
/* Allocate the comms buffers */
st->us = spi;
mutex_init(&st->buf_lock);
/* setup the industrialio driver allocated elements */
st->indio_dev = iio_allocate_device(0);
if (st->indio_dev == NULL) {
ret = -ENOMEM;
goto error_free_st;
}
st->indio_dev->name = spi->dev.driver->name;
st->indio_dev->dev.parent = &spi->dev;
st->indio_dev->attrs = &adis16080_attribute_group;
st->indio_dev->dev_data = (void *)(st);
st->indio_dev->driver_module = THIS_MODULE;
st->indio_dev->modes = INDIO_DIRECT_MODE;
ret = iio_device_register(st->indio_dev);
if (ret)
goto error_free_dev;
regdone = 1;
return 0;
error_free_dev:
if (regdone)
iio_device_unregister(st->indio_dev);
else
iio_free_device(st->indio_dev);
error_free_st:
kfree(st);
error_ret:
return ret;
}
/* fixme, confirm ordering in this function */
static int adis16080_remove(struct spi_device *spi)
{
struct adis16080_state *st = spi_get_drvdata(spi);
struct iio_dev *indio_dev = st->indio_dev;
iio_device_unregister(indio_dev);
kfree(st);
return 0;
}
static struct spi_driver adis16080_driver = {
.driver = {
.name = "adis16080",
.owner = THIS_MODULE,
},
.probe = adis16080_probe,
.remove = __devexit_p(adis16080_remove),
};
static __init int adis16080_init(void)
{
return spi_register_driver(&adis16080_driver);
}
module_init(adis16080_init);
static __exit void adis16080_exit(void)
{
spi_unregister_driver(&adis16080_driver);
}
module_exit(adis16080_exit);
MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
MODULE_DESCRIPTION("Analog Devices ADIS16080/100 Yaw Rate Gyroscope Driver");
MODULE_LICENSE("GPL v2");
|