2 * ADXRS450/ADXRS453 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>
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
24 #define ADXRS450_STARTUP_DELAY 50 /* ms */
26 /* The MSB for the spi commands */
27 #define ADXRS450_SENSOR_DATA (0x20 << 24)
28 #define ADXRS450_WRITE_DATA (0x40 << 24)
29 #define ADXRS450_READ_DATA (0x80 << 24)
31 #define ADXRS450_RATE1 0x00 /* Rate Registers */
32 #define ADXRS450_TEMP1 0x02 /* Temperature Registers */
33 #define ADXRS450_LOCST1 0x04 /* Low CST Memory Registers */
34 #define ADXRS450_HICST1 0x06 /* High CST Memory Registers */
35 #define ADXRS450_QUAD1 0x08 /* Quad Memory Registers */
36 #define ADXRS450_FAULT1 0x0A /* Fault Registers */
37 #define ADXRS450_PID1 0x0C /* Part ID Register 1 */
38 #define ADXRS450_SNH 0x0E /* Serial Number Registers, 4 bytes */
39 #define ADXRS450_SNL 0x10
40 #define ADXRS450_DNC1 0x12 /* Dynamic Null Correction Registers */
42 #define ADXRS450_P 0x01
43 #define ADXRS450_CHK 0x02
44 #define ADXRS450_CST 0x04
45 #define ADXRS450_PWR 0x08
46 #define ADXRS450_POR 0x10
47 #define ADXRS450_NVM 0x20
48 #define ADXRS450_Q 0x40
49 #define ADXRS450_PLL 0x80
50 #define ADXRS450_UV 0x100
51 #define ADXRS450_OV 0x200
52 #define ADXRS450_AMP 0x400
53 #define ADXRS450_FAIL 0x800
55 #define ADXRS450_WRERR_MASK (0x7 << 29)
57 #define ADXRS450_MAX_RX 4
58 #define ADXRS450_MAX_TX 4
60 #define ADXRS450_GET_ST(a) ((a >> 26) & 0x3)
68 * struct adxrs450_state - device instance specific data
69 * @us: actual spi_device
70 * @buf_lock: mutex to protect tx and rx
71 * @tx: transmit buffer
74 struct adxrs450_state {
75 struct spi_device *us;
76 struct mutex buf_lock;
77 __be32 tx ____cacheline_aligned;
83 * adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
84 * @indio_dev: device associated with child of actual iio_dev
85 * @reg_address: the address of the lower of the two registers, which should be
86 * an even address, the second register's address is reg_address + 1.
87 * @val: somewhere to pass back the value read
89 static int adxrs450_spi_read_reg_16(struct iio_dev *indio_dev,
93 struct spi_message msg;
94 struct adxrs450_state *st = iio_priv(indio_dev);
97 struct spi_transfer xfers[] = {
101 .len = sizeof(st->tx),
106 .len = sizeof(st->rx),
110 mutex_lock(&st->buf_lock);
111 tx = ADXRS450_READ_DATA | (reg_address << 17);
113 if (!(hweight32(tx) & 1))
116 st->tx = cpu_to_be32(tx);
117 spi_message_init(&msg);
118 spi_message_add_tail(&xfers[0], &msg);
119 spi_message_add_tail(&xfers[1], &msg);
120 ret = spi_sync(st->us, &msg);
122 dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
127 *val = (be32_to_cpu(st->rx) >> 5) & 0xFFFF;
130 mutex_unlock(&st->buf_lock);
135 * adxrs450_spi_write_reg_16() - write 2 bytes data to a register pair
136 * @indio_dev: device associated with child of actual actual iio_dev
137 * @reg_address: the address of the lower of the two registers,which should be
138 * an even address, the second register's address is reg_address + 1.
139 * @val: value to be written.
141 static int adxrs450_spi_write_reg_16(struct iio_dev *indio_dev,
145 struct adxrs450_state *st = iio_priv(indio_dev);
149 mutex_lock(&st->buf_lock);
150 tx = ADXRS450_WRITE_DATA | (reg_address << 17) | (val << 1);
152 if (!(hweight32(tx) & 1))
155 st->tx = cpu_to_be32(tx);
156 ret = spi_write(st->us, &st->tx, sizeof(st->tx));
158 dev_err(&st->us->dev, "problem while writing 16 bit register 0x%02x\n",
160 usleep_range(100, 1000); /* enforce sequential transfer delay 0.1ms */
161 mutex_unlock(&st->buf_lock);
166 * adxrs450_spi_sensor_data() - read 2 bytes sensor data
167 * @indio_dev: device associated with child of actual iio_dev
168 * @val: somewhere to pass back the value read
170 static int adxrs450_spi_sensor_data(struct iio_dev *indio_dev, s16 *val)
172 struct spi_message msg;
173 struct adxrs450_state *st = iio_priv(indio_dev);
175 struct spi_transfer xfers[] = {
179 .len = sizeof(st->tx),
184 .len = sizeof(st->rx),
188 mutex_lock(&st->buf_lock);
189 st->tx = cpu_to_be32(ADXRS450_SENSOR_DATA);
191 spi_message_init(&msg);
192 spi_message_add_tail(&xfers[0], &msg);
193 spi_message_add_tail(&xfers[1], &msg);
194 ret = spi_sync(st->us, &msg);
196 dev_err(&st->us->dev, "Problem while reading sensor data\n");
200 *val = (be32_to_cpu(st->rx) >> 10) & 0xFFFF;
203 mutex_unlock(&st->buf_lock);
208 * adxrs450_spi_initial() - use for initializing procedure.
209 * @st: device instance specific data
210 * @val: somewhere to pass back the value read
211 * @chk: Whether to perform fault check
213 static int adxrs450_spi_initial(struct adxrs450_state *st,
218 struct spi_transfer xfers = {
222 .len = sizeof(st->tx),
225 mutex_lock(&st->buf_lock);
226 tx = ADXRS450_SENSOR_DATA;
228 tx |= (ADXRS450_CHK | ADXRS450_P);
229 st->tx = cpu_to_be32(tx);
230 ret = spi_sync_transfer(st->us, &xfers, 1);
232 dev_err(&st->us->dev, "Problem while reading initializing data\n");
236 *val = be32_to_cpu(st->rx);
239 mutex_unlock(&st->buf_lock);
243 /* Recommended Startup Sequence by spec */
244 static int adxrs450_initial_setup(struct iio_dev *indio_dev)
249 struct adxrs450_state *st = iio_priv(indio_dev);
251 msleep(ADXRS450_STARTUP_DELAY*2);
252 ret = adxrs450_spi_initial(st, &t, 1);
256 dev_warn(&st->us->dev, "The initial power on response is not correct! Restart without reset?\n");
258 msleep(ADXRS450_STARTUP_DELAY);
259 ret = adxrs450_spi_initial(st, &t, 0);
263 msleep(ADXRS450_STARTUP_DELAY);
264 ret = adxrs450_spi_initial(st, &t, 0);
267 if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
268 dev_err(&st->us->dev, "The second response is not correct!\n");
272 ret = adxrs450_spi_initial(st, &t, 0);
275 if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
276 dev_err(&st->us->dev, "The third response is not correct!\n");
280 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_FAULT1, &data);
284 dev_err(&st->us->dev, "The device is not in normal status!\n");
291 static int adxrs450_write_raw(struct iio_dev *indio_dev,
292 struct iio_chan_spec const *chan,
299 case IIO_CHAN_INFO_CALIBBIAS:
300 if (val < -0x400 || val >= 0x400)
302 ret = adxrs450_spi_write_reg_16(indio_dev,
312 static int adxrs450_read_raw(struct iio_dev *indio_dev,
313 struct iio_chan_spec const *chan,
322 case IIO_CHAN_INFO_RAW:
323 switch (chan->type) {
325 ret = adxrs450_spi_sensor_data(indio_dev, &t);
332 ret = adxrs450_spi_read_reg_16(indio_dev,
336 *val = (t >> 6) + 225;
344 case IIO_CHAN_INFO_SCALE:
345 switch (chan->type) {
349 return IIO_VAL_INT_PLUS_NANO;
358 case IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW:
359 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_QUAD1, &t);
365 case IIO_CHAN_INFO_CALIBBIAS:
366 ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_DNC1, &t);
369 *val = sign_extend32(t, 9);
380 static const struct iio_chan_spec adxrs450_channels[2][2] = {
383 .type = IIO_ANGL_VEL,
385 .channel2 = IIO_MOD_Z,
386 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
387 BIT(IIO_CHAN_INFO_CALIBBIAS) |
388 BIT(IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW) |
389 BIT(IIO_CHAN_INFO_SCALE),
394 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
395 BIT(IIO_CHAN_INFO_SCALE),
400 .type = IIO_ANGL_VEL,
402 .channel2 = IIO_MOD_Z,
403 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
404 BIT(IIO_CHAN_INFO_SCALE) |
405 BIT(IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW),
410 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
411 BIT(IIO_CHAN_INFO_SCALE),
416 static const struct iio_info adxrs450_info = {
417 .driver_module = THIS_MODULE,
418 .read_raw = &adxrs450_read_raw,
419 .write_raw = &adxrs450_write_raw,
422 static int adxrs450_probe(struct spi_device *spi)
425 struct adxrs450_state *st;
426 struct iio_dev *indio_dev;
428 /* setup the industrialio driver allocated elements */
429 indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
432 st = iio_priv(indio_dev);
434 mutex_init(&st->buf_lock);
435 /* This is only used for removal purposes */
436 spi_set_drvdata(spi, indio_dev);
438 indio_dev->dev.parent = &spi->dev;
439 indio_dev->info = &adxrs450_info;
440 indio_dev->modes = INDIO_DIRECT_MODE;
441 indio_dev->channels =
442 adxrs450_channels[spi_get_device_id(spi)->driver_data];
443 indio_dev->num_channels = ARRAY_SIZE(adxrs450_channels);
444 indio_dev->name = spi->dev.driver->name;
446 ret = iio_device_register(indio_dev);
450 /* Get the device into a sane initial state */
451 ret = adxrs450_initial_setup(indio_dev);
456 iio_device_unregister(indio_dev);
460 static int adxrs450_remove(struct spi_device *spi)
462 iio_device_unregister(spi_get_drvdata(spi));
467 static const struct spi_device_id adxrs450_id[] = {
468 {"adxrs450", ID_ADXRS450},
469 {"adxrs453", ID_ADXRS453},
472 MODULE_DEVICE_TABLE(spi, adxrs450_id);
474 static struct spi_driver adxrs450_driver = {
477 .owner = THIS_MODULE,
479 .probe = adxrs450_probe,
480 .remove = adxrs450_remove,
481 .id_table = adxrs450_id,
483 module_spi_driver(adxrs450_driver);
485 MODULE_AUTHOR("Cliff Cai <cliff.cai@xxxxxxxxxx>");
486 MODULE_DESCRIPTION("Analog Devices ADXRS450/ADXRS453 Gyroscope SPI driver");
487 MODULE_LICENSE("GPL v2");