2 * ADIS16130 Digital Output, High Precision Angular Rate Sensor driver
4 * Copyright 2010 Analog Devices Inc.
6 * Licensed under the GPL-2 or later.
9 #include <linux/delay.h>
10 #include <linux/mutex.h>
11 #include <linux/device.h>
12 #include <linux/kernel.h>
13 #include <linux/spi/spi.h>
14 #include <linux/slab.h>
15 #include <linux/sysfs.h>
16 #include <linux/list.h>
17 #include <linux/module.h>
22 #define ADIS16130_CON 0x0
23 #define ADIS16130_CON_RD (1 << 6)
24 #define ADIS16130_IOP 0x1
26 /* 1 = data-ready signal low when unread data on all channels; */
27 #define ADIS16130_IOP_ALL_RDY (1 << 3)
28 #define ADIS16130_IOP_SYNC (1 << 0) /* 1 = synchronization enabled */
29 #define ADIS16130_RATEDATA 0x8 /* Gyroscope output, rate of rotation */
30 #define ADIS16130_TEMPDATA 0xA /* Temperature output */
31 #define ADIS16130_RATECS 0x28 /* Gyroscope channel setup */
32 #define ADIS16130_RATECS_EN (1 << 3) /* 1 = channel enable; */
33 #define ADIS16130_TEMPCS 0x2A /* Temperature channel setup */
34 #define ADIS16130_TEMPCS_EN (1 << 3)
35 #define ADIS16130_RATECONV 0x30
36 #define ADIS16130_TEMPCONV 0x32
37 #define ADIS16130_MODE 0x38
38 #define ADIS16130_MODE_24BIT (1 << 1) /* 1 = 24-bit resolution; */
41 * struct adis16130_state - device instance specific data
42 * @us: actual spi_device to write data
43 * @buf_lock: mutex to protect tx and rx
44 * @buf: unified tx/rx buffer
46 struct adis16130_state {
47 struct spi_device *us;
48 struct mutex buf_lock;
49 u8 buf[4] ____cacheline_aligned;
52 static int adis16130_spi_read(struct iio_dev *indio_dev, u8 reg_addr, u32 *val)
55 struct adis16130_state *st = iio_priv(indio_dev);
56 struct spi_message msg;
57 struct spi_transfer xfer = {
63 mutex_lock(&st->buf_lock);
65 st->buf[0] = ADIS16130_CON_RD | reg_addr;
66 st->buf[1] = st->buf[2] = st->buf[3] = 0;
68 spi_message_init(&msg);
69 spi_message_add_tail(&xfer, &msg);
70 ret = spi_sync(st->us, &msg);
71 ret = spi_read(st->us, st->buf, 4);
74 *val = (st->buf[1] << 16) | (st->buf[2] << 8) | st->buf[3];
75 mutex_unlock(&st->buf_lock);
80 static int adis16130_read_raw(struct iio_dev *indio_dev,
81 struct iio_chan_spec const *chan,
88 /* Take the iio_dev status lock */
89 mutex_lock(&indio_dev->mlock);
90 ret = adis16130_spi_read(indio_dev, chan->address, &temp);
91 mutex_unlock(&indio_dev->mlock);
98 static const struct iio_chan_spec adis16130_channels[] = {
102 .channel2 = IIO_MOD_Z,
103 .address = ADIS16130_RATEDATA,
108 .address = ADIS16130_TEMPDATA,
112 static const struct iio_info adis16130_info = {
113 .read_raw = &adis16130_read_raw,
114 .driver_module = THIS_MODULE,
117 static int __devinit adis16130_probe(struct spi_device *spi)
120 struct adis16130_state *st;
121 struct iio_dev *indio_dev;
123 /* setup the industrialio driver allocated elements */
124 indio_dev = iio_allocate_device(sizeof(*st));
125 if (indio_dev == NULL) {
129 st = iio_priv(indio_dev);
130 /* this is only used for removal purposes */
131 spi_set_drvdata(spi, indio_dev);
133 mutex_init(&st->buf_lock);
134 indio_dev->name = spi->dev.driver->name;
135 indio_dev->channels = adis16130_channels;
136 indio_dev->num_channels = ARRAY_SIZE(adis16130_channels);
137 indio_dev->dev.parent = &spi->dev;
138 indio_dev->info = &adis16130_info;
139 indio_dev->modes = INDIO_DIRECT_MODE;
141 ret = iio_device_register(indio_dev);
148 iio_free_device(indio_dev);
154 /* fixme, confirm ordering in this function */
155 static int adis16130_remove(struct spi_device *spi)
157 iio_device_unregister(spi_get_drvdata(spi));
162 static struct spi_driver adis16130_driver = {
165 .owner = THIS_MODULE,
167 .probe = adis16130_probe,
168 .remove = __devexit_p(adis16130_remove),
171 static __init int adis16130_init(void)
173 return spi_register_driver(&adis16130_driver);
175 module_init(adis16130_init);
177 static __exit void adis16130_exit(void)
179 spi_unregister_driver(&adis16130_driver);
181 module_exit(adis16130_exit);
183 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
184 MODULE_DESCRIPTION("Analog Devices ADIS16130 High Precision Angular Rate");
185 MODULE_LICENSE("GPL v2");