xref: /openbmc/linux/drivers/iio/gyro/adxrs450.c (revision 966d2f4e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ADXRS450/ADXRS453 Digital Output Gyroscope Driver
4  *
5  * Copyright 2011 Analog Devices Inc.
6  */
7 
8 #include <linux/interrupt.h>
9 #include <linux/irq.h>
10 #include <linux/delay.h>
11 #include <linux/mutex.h>
12 #include <linux/device.h>
13 #include <linux/kernel.h>
14 #include <linux/spi/spi.h>
15 #include <linux/slab.h>
16 #include <linux/sysfs.h>
17 #include <linux/list.h>
18 #include <linux/module.h>
19 
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 
23 #define ADXRS450_STARTUP_DELAY	50 /* ms */
24 
25 /* The MSB for the spi commands */
26 #define ADXRS450_SENSOR_DATA    (0x20 << 24)
27 #define ADXRS450_WRITE_DATA	(0x40 << 24)
28 #define ADXRS450_READ_DATA	(0x80 << 24)
29 
30 #define ADXRS450_RATE1	0x00	/* Rate Registers */
31 #define ADXRS450_TEMP1	0x02	/* Temperature Registers */
32 #define ADXRS450_LOCST1	0x04	/* Low CST Memory Registers */
33 #define ADXRS450_HICST1	0x06	/* High CST Memory Registers */
34 #define ADXRS450_QUAD1	0x08	/* Quad Memory Registers */
35 #define ADXRS450_FAULT1	0x0A	/* Fault Registers */
36 #define ADXRS450_PID1	0x0C	/* Part ID Register 1 */
37 #define ADXRS450_SNH	0x0E	/* Serial Number Registers, 4 bytes */
38 #define ADXRS450_SNL	0x10
39 #define ADXRS450_DNC1	0x12	/* Dynamic Null Correction Registers */
40 /* Check bits */
41 #define ADXRS450_P	0x01
42 #define ADXRS450_CHK	0x02
43 #define ADXRS450_CST	0x04
44 #define ADXRS450_PWR	0x08
45 #define ADXRS450_POR	0x10
46 #define ADXRS450_NVM	0x20
47 #define ADXRS450_Q	0x40
48 #define ADXRS450_PLL	0x80
49 #define ADXRS450_UV	0x100
50 #define ADXRS450_OV	0x200
51 #define ADXRS450_AMP	0x400
52 #define ADXRS450_FAIL	0x800
53 
54 #define ADXRS450_WRERR_MASK	(0x7 << 29)
55 
56 #define ADXRS450_MAX_RX 4
57 #define ADXRS450_MAX_TX 4
58 
59 #define ADXRS450_GET_ST(a)	((a >> 26) & 0x3)
60 
61 enum {
62 	ID_ADXRS450,
63 	ID_ADXRS453,
64 };
65 
66 /**
67  * struct adxrs450_state - device instance specific data
68  * @us:			actual spi_device
69  * @buf_lock:		mutex to protect tx and rx
70  * @tx:			transmit buffer
71  * @rx:			receive buffer
72  **/
73 struct adxrs450_state {
74 	struct spi_device	*us;
75 	struct mutex		buf_lock;
76 	__be32			tx __aligned(IIO_DMA_MINALIGN);
77 	__be32			rx;
78 
79 };
80 
81 /**
82  * adxrs450_spi_read_reg_16() - read 2 bytes from a register pair
83  * @indio_dev: device associated with child of actual iio_dev
84  * @reg_address: the address of the lower of the two registers, which should be
85  *	an even address, the second register's address is reg_address + 1.
86  * @val: somewhere to pass back the value read
87  **/
adxrs450_spi_read_reg_16(struct iio_dev * indio_dev,u8 reg_address,u16 * val)88 static int adxrs450_spi_read_reg_16(struct iio_dev *indio_dev,
89 				    u8 reg_address,
90 				    u16 *val)
91 {
92 	struct adxrs450_state *st = iio_priv(indio_dev);
93 	u32 tx;
94 	int ret;
95 	struct spi_transfer xfers[] = {
96 		{
97 			.tx_buf = &st->tx,
98 			.bits_per_word = 8,
99 			.len = sizeof(st->tx),
100 			.cs_change = 1,
101 		}, {
102 			.rx_buf = &st->rx,
103 			.bits_per_word = 8,
104 			.len = sizeof(st->rx),
105 		},
106 	};
107 
108 	mutex_lock(&st->buf_lock);
109 	tx = ADXRS450_READ_DATA | (reg_address << 17);
110 
111 	if (!(hweight32(tx) & 1))
112 		tx |= ADXRS450_P;
113 
114 	st->tx = cpu_to_be32(tx);
115 	ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
116 	if (ret) {
117 		dev_err(&st->us->dev, "problem while reading 16 bit register 0x%02x\n",
118 				reg_address);
119 		goto error_ret;
120 	}
121 
122 	*val = (be32_to_cpu(st->rx) >> 5) & 0xFFFF;
123 
124 error_ret:
125 	mutex_unlock(&st->buf_lock);
126 	return ret;
127 }
128 
129 /**
130  * adxrs450_spi_write_reg_16() - write 2 bytes data to a register pair
131  * @indio_dev: device associated with child of actual actual iio_dev
132  * @reg_address: the address of the lower of the two registers,which should be
133  *	an even address, the second register's address is reg_address + 1.
134  * @val: value to be written.
135  **/
adxrs450_spi_write_reg_16(struct iio_dev * indio_dev,u8 reg_address,u16 val)136 static int adxrs450_spi_write_reg_16(struct iio_dev *indio_dev,
137 				     u8 reg_address,
138 				     u16 val)
139 {
140 	struct adxrs450_state *st = iio_priv(indio_dev);
141 	u32 tx;
142 	int ret;
143 
144 	mutex_lock(&st->buf_lock);
145 	tx = ADXRS450_WRITE_DATA | (reg_address << 17) | (val << 1);
146 
147 	if (!(hweight32(tx) & 1))
148 		tx |= ADXRS450_P;
149 
150 	st->tx = cpu_to_be32(tx);
151 	ret = spi_write(st->us, &st->tx, sizeof(st->tx));
152 	if (ret)
153 		dev_err(&st->us->dev, "problem while writing 16 bit register 0x%02x\n",
154 			reg_address);
155 	usleep_range(100, 1000); /* enforce sequential transfer delay 0.1ms */
156 	mutex_unlock(&st->buf_lock);
157 	return ret;
158 }
159 
160 /**
161  * adxrs450_spi_sensor_data() - read 2 bytes sensor data
162  * @indio_dev: device associated with child of actual iio_dev
163  * @val: somewhere to pass back the value read
164  **/
adxrs450_spi_sensor_data(struct iio_dev * indio_dev,s16 * val)165 static int adxrs450_spi_sensor_data(struct iio_dev *indio_dev, s16 *val)
166 {
167 	struct adxrs450_state *st = iio_priv(indio_dev);
168 	int ret;
169 	struct spi_transfer xfers[] = {
170 		{
171 			.tx_buf = &st->tx,
172 			.bits_per_word = 8,
173 			.len = sizeof(st->tx),
174 			.cs_change = 1,
175 		}, {
176 			.rx_buf = &st->rx,
177 			.bits_per_word = 8,
178 			.len = sizeof(st->rx),
179 		},
180 	};
181 
182 	mutex_lock(&st->buf_lock);
183 	st->tx = cpu_to_be32(ADXRS450_SENSOR_DATA);
184 
185 	ret = spi_sync_transfer(st->us, xfers, ARRAY_SIZE(xfers));
186 	if (ret) {
187 		dev_err(&st->us->dev, "Problem while reading sensor data\n");
188 		goto error_ret;
189 	}
190 
191 	*val = (be32_to_cpu(st->rx) >> 10) & 0xFFFF;
192 
193 error_ret:
194 	mutex_unlock(&st->buf_lock);
195 	return ret;
196 }
197 
198 /**
199  * adxrs450_spi_initial() - use for initializing procedure.
200  * @st: device instance specific data
201  * @val: somewhere to pass back the value read
202  * @chk: Whether to perform fault check
203  **/
adxrs450_spi_initial(struct adxrs450_state * st,u32 * val,char chk)204 static int adxrs450_spi_initial(struct adxrs450_state *st,
205 		u32 *val, char chk)
206 {
207 	int ret;
208 	u32 tx;
209 	struct spi_transfer xfers = {
210 		.tx_buf = &st->tx,
211 		.rx_buf = &st->rx,
212 		.bits_per_word = 8,
213 		.len = sizeof(st->tx),
214 	};
215 
216 	mutex_lock(&st->buf_lock);
217 	tx = ADXRS450_SENSOR_DATA;
218 	if (chk)
219 		tx |= (ADXRS450_CHK | ADXRS450_P);
220 	st->tx = cpu_to_be32(tx);
221 	ret = spi_sync_transfer(st->us, &xfers, 1);
222 	if (ret) {
223 		dev_err(&st->us->dev, "Problem while reading initializing data\n");
224 		goto error_ret;
225 	}
226 
227 	*val = be32_to_cpu(st->rx);
228 
229 error_ret:
230 	mutex_unlock(&st->buf_lock);
231 	return ret;
232 }
233 
234 /* Recommended Startup Sequence by spec */
adxrs450_initial_setup(struct iio_dev * indio_dev)235 static int adxrs450_initial_setup(struct iio_dev *indio_dev)
236 {
237 	u32 t;
238 	u16 data;
239 	int ret;
240 	struct adxrs450_state *st = iio_priv(indio_dev);
241 
242 	msleep(ADXRS450_STARTUP_DELAY*2);
243 	ret = adxrs450_spi_initial(st, &t, 1);
244 	if (ret)
245 		return ret;
246 	if (t != 0x01)
247 		dev_warn(&st->us->dev, "The initial power on response is not correct! Restart without reset?\n");
248 
249 	msleep(ADXRS450_STARTUP_DELAY);
250 	ret = adxrs450_spi_initial(st, &t, 0);
251 	if (ret)
252 		return ret;
253 
254 	msleep(ADXRS450_STARTUP_DELAY);
255 	ret = adxrs450_spi_initial(st, &t, 0);
256 	if (ret)
257 		return ret;
258 	if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
259 		dev_err(&st->us->dev, "The second response is not correct!\n");
260 		return -EIO;
261 
262 	}
263 	ret = adxrs450_spi_initial(st, &t, 0);
264 	if (ret)
265 		return ret;
266 	if (((t & 0xff) | 0x01) != 0xff || ADXRS450_GET_ST(t) != 2) {
267 		dev_err(&st->us->dev, "The third response is not correct!\n");
268 		return -EIO;
269 
270 	}
271 	ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_FAULT1, &data);
272 	if (ret)
273 		return ret;
274 	if (data & 0x0fff) {
275 		dev_err(&st->us->dev, "The device is not in normal status!\n");
276 		return -EINVAL;
277 	}
278 
279 	return 0;
280 }
281 
adxrs450_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)282 static int adxrs450_write_raw(struct iio_dev *indio_dev,
283 			      struct iio_chan_spec const *chan,
284 			      int val,
285 			      int val2,
286 			      long mask)
287 {
288 	int ret;
289 	switch (mask) {
290 	case IIO_CHAN_INFO_CALIBBIAS:
291 		if (val < -0x400 || val >= 0x400)
292 			return -EINVAL;
293 		ret = adxrs450_spi_write_reg_16(indio_dev,
294 						ADXRS450_DNC1, val);
295 		break;
296 	default:
297 		ret = -EINVAL;
298 		break;
299 	}
300 	return ret;
301 }
302 
adxrs450_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)303 static int adxrs450_read_raw(struct iio_dev *indio_dev,
304 			     struct iio_chan_spec const *chan,
305 			     int *val,
306 			     int *val2,
307 			     long mask)
308 {
309 	int ret;
310 	s16 t;
311 
312 	switch (mask) {
313 	case IIO_CHAN_INFO_RAW:
314 		switch (chan->type) {
315 		case IIO_ANGL_VEL:
316 			ret = adxrs450_spi_sensor_data(indio_dev, &t);
317 			if (ret)
318 				break;
319 			*val = t;
320 			ret = IIO_VAL_INT;
321 			break;
322 		case IIO_TEMP:
323 			ret = adxrs450_spi_read_reg_16(indio_dev,
324 						       ADXRS450_TEMP1, &t);
325 			if (ret)
326 				break;
327 			*val = (t >> 6) + 225;
328 			ret = IIO_VAL_INT;
329 			break;
330 		default:
331 			ret = -EINVAL;
332 			break;
333 		}
334 		break;
335 	case IIO_CHAN_INFO_SCALE:
336 		switch (chan->type) {
337 		case IIO_ANGL_VEL:
338 			*val = 0;
339 			*val2 = 218166;
340 			return IIO_VAL_INT_PLUS_NANO;
341 		case IIO_TEMP:
342 			*val = 200;
343 			*val2 = 0;
344 			return IIO_VAL_INT;
345 		default:
346 			return -EINVAL;
347 		}
348 	case IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW:
349 		ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_QUAD1, &t);
350 		if (ret)
351 			break;
352 		*val = t;
353 		ret = IIO_VAL_INT;
354 		break;
355 	case IIO_CHAN_INFO_CALIBBIAS:
356 		ret = adxrs450_spi_read_reg_16(indio_dev, ADXRS450_DNC1, &t);
357 		if (ret)
358 			break;
359 		*val = sign_extend32(t, 9);
360 		ret = IIO_VAL_INT;
361 		break;
362 	default:
363 		ret = -EINVAL;
364 		break;
365 	}
366 
367 	return ret;
368 }
369 
370 static const struct iio_chan_spec adxrs450_channels[2][2] = {
371 	[ID_ADXRS450] = {
372 		{
373 			.type = IIO_ANGL_VEL,
374 			.modified = 1,
375 			.channel2 = IIO_MOD_Z,
376 			.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
377 			BIT(IIO_CHAN_INFO_CALIBBIAS) |
378 			BIT(IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW) |
379 			BIT(IIO_CHAN_INFO_SCALE),
380 		}, {
381 			.type = IIO_TEMP,
382 			.indexed = 1,
383 			.channel = 0,
384 			.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
385 			BIT(IIO_CHAN_INFO_SCALE),
386 		}
387 	},
388 	[ID_ADXRS453] = {
389 		{
390 			.type = IIO_ANGL_VEL,
391 			.modified = 1,
392 			.channel2 = IIO_MOD_Z,
393 			.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
394 			BIT(IIO_CHAN_INFO_SCALE) |
395 			BIT(IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW),
396 		}, {
397 			.type = IIO_TEMP,
398 			.indexed = 1,
399 			.channel = 0,
400 			.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
401 			BIT(IIO_CHAN_INFO_SCALE),
402 		}
403 	},
404 };
405 
406 static const struct iio_info adxrs450_info = {
407 	.read_raw = &adxrs450_read_raw,
408 	.write_raw = &adxrs450_write_raw,
409 };
410 
adxrs450_probe(struct spi_device * spi)411 static int adxrs450_probe(struct spi_device *spi)
412 {
413 	int ret;
414 	struct adxrs450_state *st;
415 	struct iio_dev *indio_dev;
416 
417 	/* setup the industrialio driver allocated elements */
418 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
419 	if (!indio_dev)
420 		return -ENOMEM;
421 	st = iio_priv(indio_dev);
422 	st->us = spi;
423 	mutex_init(&st->buf_lock);
424 	/* This is only used for removal purposes */
425 	spi_set_drvdata(spi, indio_dev);
426 
427 	indio_dev->info = &adxrs450_info;
428 	indio_dev->modes = INDIO_DIRECT_MODE;
429 	indio_dev->channels =
430 		adxrs450_channels[spi_get_device_id(spi)->driver_data];
431 	indio_dev->num_channels = ARRAY_SIZE(adxrs450_channels);
432 	indio_dev->name = spi->dev.driver->name;
433 
434 	ret = devm_iio_device_register(&spi->dev, indio_dev);
435 	if (ret)
436 		return ret;
437 
438 	/* Get the device into a sane initial state */
439 	ret = adxrs450_initial_setup(indio_dev);
440 	if (ret)
441 		return ret;
442 
443 	return 0;
444 }
445 
446 static const struct spi_device_id adxrs450_id[] = {
447 	{"adxrs450", ID_ADXRS450},
448 	{"adxrs453", ID_ADXRS453},
449 	{}
450 };
451 MODULE_DEVICE_TABLE(spi, adxrs450_id);
452 
453 static struct spi_driver adxrs450_driver = {
454 	.driver = {
455 		.name = "adxrs450",
456 	},
457 	.probe = adxrs450_probe,
458 	.id_table	= adxrs450_id,
459 };
460 module_spi_driver(adxrs450_driver);
461 
462 MODULE_AUTHOR("Cliff Cai <cliff.cai@xxxxxxxxxx>");
463 MODULE_DESCRIPTION("Analog Devices ADXRS450/ADXRS453 Gyroscope SPI driver");
464 MODULE_LICENSE("GPL v2");
465