2 * ADXRS450 Digital Output Gyroscope Driver
4 * Copyright 2011 Analog Devices Inc.
6 * Licensed under the GPL-2.
9 #include <linux/interrupt.h>
10 #include <linux/irq.h>
11 #include <linux/delay.h>
12 #include <linux/mutex.h>
13 #include <linux/device.h>
14 #include <linux/kernel.h>
15 #include <linux/spi/spi.h>
16 #include <linux/slab.h>
17 #include <linux/sysfs.h>
18 #include <linux/list.h>
19 #include <linux/module.h>
27 * adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
28 * @dev: device associated with child of actual iio_dev
29 * @reg_address: the address of the lower of the two registers,which should be an even address,
30 * Second register's address is reg_address + 1.
31 * @val: somewhere to pass back the value read
33 static int adxrs450_spi_read_reg_16(struct iio_dev *indio_dev,
37 struct adxrs450_state *st = iio_priv(indio_dev);
40 mutex_lock(&st->buf_lock);
41 st->tx[0] = ADXRS450_READ_DATA | (reg_address >> 7);
42 st->tx[1] = reg_address << 1;
46 if (!(hweight32(be32_to_cpu(*(u32 *)st->tx)) & 1))
47 st->tx[3] |= ADXRS450_P;
49 ret = spi_write(st->us, st->tx, 4);
51 dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
55 ret = spi_read(st->us, st->rx, 4);
57 dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
62 *val = (be32_to_cpu(*(u32 *)st->rx) >> 5) & 0xFFFF;
65 mutex_unlock(&st->buf_lock);
70 * adxrs450_spi_write_reg_16() - write 2 bytes data to a register pair
71 * @dev: device associated with child of actual actual iio_dev
72 * @reg_address: the address of the lower of the two registers,which should be an even address,
73 * Second register's address is reg_address + 1.
74 * @val: value to be written.
76 static int adxrs450_spi_write_reg_16(struct iio_dev *indio_dev,
80 struct adxrs450_state *st = iio_priv(indio_dev);
83 mutex_lock(&st->buf_lock);
84 st->tx[0] = ADXRS450_WRITE_DATA | reg_address >> 7;
85 st->tx[1] = reg_address << 1 | val >> 15;
89 if (!(hweight32(be32_to_cpu(*(u32 *)st->tx)) & 1))
90 st->tx[3] |= ADXRS450_P;
92 ret = spi_write(st->us, st->tx, 4);
94 dev_err(&st->us->dev, "problem while writing 16 bit register 0x%02x\n",
96 msleep(1); /* enforce sequential transfer delay 0.1ms */
97 mutex_unlock(&st->buf_lock);
102 * adxrs450_spi_sensor_data() - read 2 bytes sensor data
103 * @dev: device associated with child of actual iio_dev
104 * @val: somewhere to pass back the value read
106 static int adxrs450_spi_sensor_data(struct iio_dev *indio_dev, s16 *val)
108 struct adxrs450_state *st = iio_priv(indio_dev);
111 mutex_lock(&st->buf_lock);
112 st->tx[0] = ADXRS450_SENSOR_DATA;
117 ret = spi_write(st->us, st->tx, 4);
119 dev_err(&st->us->dev, "Problem while reading sensor data\n");
123 ret = spi_read(st->us, st->rx, 4);
125 dev_err(&st->us->dev, "Problem while reading sensor data\n");
129 *val = (be32_to_cpu(*(u32 *)st->rx) >> 10) & 0xFFFF;
132 mutex_unlock(&st->buf_lock);
137 * adxrs450_spi_initial() - use for initializing procedure.
138 * @st: device instance specific data
139 * @val: somewhere to pass back the value read
141 static int adxrs450_spi_initial(struct adxrs450_state *st,
144 struct spi_message msg;
146 struct spi_transfer xfers = {
153 mutex_lock(&st->buf_lock);
154 st->tx[0] = ADXRS450_SENSOR_DATA;
159 st->tx[3] |= (ADXRS450_CHK | ADXRS450_P);
160 spi_message_init(&msg);
161 spi_message_add_tail(&xfers, &msg);
162 ret = spi_sync(st->us, &msg);
164 dev_err(&st->us->dev, "Problem while reading initializing data\n");
168 *val = be32_to_cpu(*(u32 *)st->rx);
171 mutex_unlock(&st->buf_lock);
175 /* Recommended Startup Sequence by spec */
176 static int adxrs450_initial_setup(struct iio_dev *indio_dev)
181 struct adxrs450_state *st = iio_priv(indio_dev);
183 msleep(ADXRS450_STARTUP_DELAY*2);
184 ret = adxrs450_spi_initial(st, &t, 1);
188 dev_warn(&st->us->dev, "The initial power on response "
189 "is not correct! Restart without reset?\n");
191 msleep(ADXRS450_STARTUP_DELAY);
192 ret = adxrs450_spi_initial(st, &t, 0);
196 msleep(ADXRS450_STARTUP_DELAY);
197 ret = adxrs450_spi_initial(st, &t, 0);
200 if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
201 dev_err(&st->us->dev, "The second response is not correct!\n");
205 ret = adxrs450_spi_initial(st, &t, 0);
208 if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
209 dev_err(&st->us->dev, "The third response is not correct!\n");
213 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_FAULT1, &data);
217 dev_err(&st->us->dev, "The device is not in normal status!\n");
220 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_PID1, &data);
223 dev_info(&st->us->dev, "The Part ID is 0x%x\n", data);
225 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_SNL, &data);
229 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_SNH, &data);
233 dev_info(&st->us->dev, "The Serial Number is 0x%x\n", t);
238 static int adxrs450_write_raw(struct iio_dev *indio_dev,
239 struct iio_chan_spec const *chan,
246 case IIO_CHAN_INFO_CALIBBIAS:
247 ret = adxrs450_spi_write_reg_16(indio_dev,
258 static int adxrs450_read_raw(struct iio_dev *indio_dev,
259 struct iio_chan_spec const *chan,
269 switch (chan->type) {
271 ret = adxrs450_spi_sensor_data(indio_dev, &t);
278 ret = adxrs450_spi_read_reg_16(indio_dev,
279 ADXRS450_TEMP1, &ut);
290 case IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW:
291 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_QUAD1, &t);
305 static const struct iio_chan_spec adxrs450_channels[] = {
307 .type = IIO_ANGL_VEL,
309 .channel2 = IIO_MOD_Z,
310 .info_mask = IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT |
311 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SEPARATE_BIT,
319 static const struct iio_info adxrs450_info = {
320 .driver_module = THIS_MODULE,
321 .read_raw = &adxrs450_read_raw,
322 .write_raw = &adxrs450_write_raw,
325 static int __devinit adxrs450_probe(struct spi_device *spi)
328 struct adxrs450_state *st;
329 struct iio_dev *indio_dev;
331 /* setup the industrialio driver allocated elements */
332 indio_dev = iio_allocate_device(sizeof(*st));
333 if (indio_dev == NULL) {
337 st = iio_priv(indio_dev);
339 mutex_init(&st->buf_lock);
340 /* This is only used for removal purposes */
341 spi_set_drvdata(spi, indio_dev);
343 indio_dev->dev.parent = &spi->dev;
344 indio_dev->info = &adxrs450_info;
345 indio_dev->modes = INDIO_DIRECT_MODE;
346 indio_dev->channels = adxrs450_channels;
347 indio_dev->num_channels = ARRAY_SIZE(adxrs450_channels);
348 indio_dev->name = spi->dev.driver->name;
350 ret = iio_device_register(indio_dev);
354 /* Get the device into a sane initial state */
355 ret = adxrs450_initial_setup(indio_dev);
360 iio_device_unregister(indio_dev);
362 iio_free_device(indio_dev);
368 static int adxrs450_remove(struct spi_device *spi)
370 iio_device_unregister(spi_get_drvdata(spi));
371 iio_free_device(spi_get_drvdata(spi));
376 static struct spi_driver adxrs450_driver = {
379 .owner = THIS_MODULE,
381 .probe = adxrs450_probe,
382 .remove = __devexit_p(adxrs450_remove),
384 module_spi_driver(adxrs450_driver);
386 MODULE_AUTHOR("Cliff Cai <cliff.cai@xxxxxxxxxx>");
387 MODULE_DESCRIPTION("Analog Devices ADXRS450 Gyroscope SPI driver");
388 MODULE_LICENSE("GPL v2");
389 MODULE_ALIAS("spi:adxrs450");