2 * ADIS16080/100 Yaw Rate Gyroscope with SPI driver
4 * Copyright 2010 Analog Devices Inc.
6 * Licensed under the GPL-2 or later.
8 #include <linux/gpio.h>
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>
20 #include "../adc/adc.h"
22 #define ADIS16080_DIN_GYRO (0 << 10) /* Gyroscope output */
23 #define ADIS16080_DIN_TEMP (1 << 10) /* Temperature output */
24 #define ADIS16080_DIN_AIN1 (2 << 10)
25 #define ADIS16080_DIN_AIN2 (3 << 10)
28 * 1: Write contents on DIN to control register.
29 * 0: No changes to control register.
32 #define ADIS16080_DIN_WRITE (1 << 15)
35 * struct adis16080_state - device instance specific data
36 * @us: actual spi_device to write data
37 * @indio_dev: industrial I/O device structure
38 * @buf: transmit or receive buffer
39 * @buf_lock: mutex to protect tx and rx
41 struct adis16080_state {
42 struct spi_device *us;
43 struct iio_dev *indio_dev;
44 struct mutex buf_lock;
46 u8 buf[2] ____cacheline_aligned;
49 static int adis16080_spi_write(struct device *dev,
53 struct iio_dev *indio_dev = dev_get_drvdata(dev);
54 struct adis16080_state *st = iio_dev_get_devdata(indio_dev);
56 mutex_lock(&st->buf_lock);
57 st->buf[0] = val >> 8;
60 ret = spi_write(st->us, st->buf, 2);
61 mutex_unlock(&st->buf_lock);
66 static int adis16080_spi_read(struct device *dev,
70 struct iio_dev *indio_dev = dev_get_drvdata(dev);
71 struct adis16080_state *st = iio_dev_get_devdata(indio_dev);
73 mutex_lock(&st->buf_lock);
75 ret = spi_read(st->us, st->buf, 2);
78 *val = ((st->buf[0] & 0xF) << 8) | st->buf[1];
79 mutex_unlock(&st->buf_lock);
84 static ssize_t adis16080_read(struct device *dev,
85 struct device_attribute *attr,
88 struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
89 struct iio_dev *indio_dev = dev_get_drvdata(dev);
93 /* Take the iio_dev status lock */
94 mutex_lock(&indio_dev->mlock);
95 ret = adis16080_spi_write(dev,
96 this_attr->address | ADIS16080_DIN_WRITE);
99 ret = adis16080_spi_read(dev, &val);
101 mutex_unlock(&indio_dev->mlock);
104 return sprintf(buf, "%d\n", val);
108 static IIO_DEV_ATTR_GYRO_Z(adis16080_read, ADIS16080_DIN_GYRO);
109 static IIO_DEVICE_ATTR(temp_raw, S_IRUGO, adis16080_read, NULL,
111 static IIO_DEV_ATTR_IN_RAW(0, adis16080_read, ADIS16080_DIN_AIN1);
112 static IIO_DEV_ATTR_IN_RAW(1, adis16080_read, ADIS16080_DIN_AIN2);
114 static struct attribute *adis16080_attributes[] = {
115 &iio_dev_attr_gyro_z_raw.dev_attr.attr,
116 &iio_dev_attr_temp_raw.dev_attr.attr,
117 &iio_dev_attr_in0_raw.dev_attr.attr,
118 &iio_dev_attr_in1_raw.dev_attr.attr,
122 static const struct attribute_group adis16080_attribute_group = {
123 .attrs = adis16080_attributes,
126 static const struct iio_info adis16080_info = {
127 .attrs = &adis16080_attribute_group,
128 .driver_module = THIS_MODULE,
131 static int __devinit adis16080_probe(struct spi_device *spi)
133 int ret, regdone = 0;
134 struct adis16080_state *st = kzalloc(sizeof *st, GFP_KERNEL);
139 /* this is only used for removal purposes */
140 spi_set_drvdata(spi, st);
142 /* Allocate the comms buffers */
144 mutex_init(&st->buf_lock);
145 /* setup the industrialio driver allocated elements */
146 st->indio_dev = iio_allocate_device(0);
147 if (st->indio_dev == NULL) {
152 st->indio_dev->name = spi->dev.driver->name;
153 st->indio_dev->dev.parent = &spi->dev;
154 st->indio_dev->info = &adis16080_info;
155 st->indio_dev->dev_data = (void *)(st);
156 st->indio_dev->modes = INDIO_DIRECT_MODE;
158 ret = iio_device_register(st->indio_dev);
167 iio_device_unregister(st->indio_dev);
169 iio_free_device(st->indio_dev);
176 /* fixme, confirm ordering in this function */
177 static int adis16080_remove(struct spi_device *spi)
179 struct adis16080_state *st = spi_get_drvdata(spi);
180 struct iio_dev *indio_dev = st->indio_dev;
182 iio_device_unregister(indio_dev);
188 static struct spi_driver adis16080_driver = {
191 .owner = THIS_MODULE,
193 .probe = adis16080_probe,
194 .remove = __devexit_p(adis16080_remove),
197 static __init int adis16080_init(void)
199 return spi_register_driver(&adis16080_driver);
201 module_init(adis16080_init);
203 static __exit void adis16080_exit(void)
205 spi_unregister_driver(&adis16080_driver);
207 module_exit(adis16080_exit);
209 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
210 MODULE_DESCRIPTION("Analog Devices ADIS16080/100 Yaw Rate Gyroscope Driver");
211 MODULE_LICENSE("GPL v2");