xref: /openbmc/linux/drivers/iio/gyro/mpu3050-core.c (revision b8265621)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * MPU3050 gyroscope driver
4  *
5  * Copyright (C) 2016 Linaro Ltd.
6  * Author: Linus Walleij <linus.walleij@linaro.org>
7  *
8  * Based on the input subsystem driver, Copyright (C) 2011 Wistron Co.Ltd
9  * Joseph Lai <joseph_lai@wistron.com> and trimmed down by
10  * Alan Cox <alan@linux.intel.com> in turn based on bma023.c.
11  * Device behaviour based on a misc driver posted by Nathan Royer in 2011.
12  *
13  * TODO: add support for setting up the low pass 3dB frequency.
14  */
15 
16 #include <linux/bitops.h>
17 #include <linux/delay.h>
18 #include <linux/err.h>
19 #include <linux/iio/buffer.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/trigger.h>
23 #include <linux/iio/trigger_consumer.h>
24 #include <linux/iio/triggered_buffer.h>
25 #include <linux/interrupt.h>
26 #include <linux/module.h>
27 #include <linux/pm_runtime.h>
28 #include <linux/random.h>
29 #include <linux/slab.h>
30 
31 #include "mpu3050.h"
32 
33 #define MPU3050_CHIP_ID		0x68
34 #define MPU3050_CHIP_ID_MASK	0x7E
35 
36 /*
37  * Register map: anything suffixed *_H is a big-endian high byte and always
38  * followed by the corresponding low byte (*_L) even though these are not
39  * explicitly included in the register definitions.
40  */
41 #define MPU3050_CHIP_ID_REG	0x00
42 #define MPU3050_PRODUCT_ID_REG	0x01
43 #define MPU3050_XG_OFFS_TC	0x05
44 #define MPU3050_YG_OFFS_TC	0x08
45 #define MPU3050_ZG_OFFS_TC	0x0B
46 #define MPU3050_X_OFFS_USR_H	0x0C
47 #define MPU3050_Y_OFFS_USR_H	0x0E
48 #define MPU3050_Z_OFFS_USR_H	0x10
49 #define MPU3050_FIFO_EN		0x12
50 #define MPU3050_AUX_VDDIO	0x13
51 #define MPU3050_SLV_ADDR	0x14
52 #define MPU3050_SMPLRT_DIV	0x15
53 #define MPU3050_DLPF_FS_SYNC	0x16
54 #define MPU3050_INT_CFG		0x17
55 #define MPU3050_AUX_ADDR	0x18
56 #define MPU3050_INT_STATUS	0x1A
57 #define MPU3050_TEMP_H		0x1B
58 #define MPU3050_XOUT_H		0x1D
59 #define MPU3050_YOUT_H		0x1F
60 #define MPU3050_ZOUT_H		0x21
61 #define MPU3050_DMP_CFG1	0x35
62 #define MPU3050_DMP_CFG2	0x36
63 #define MPU3050_BANK_SEL	0x37
64 #define MPU3050_MEM_START_ADDR	0x38
65 #define MPU3050_MEM_R_W		0x39
66 #define MPU3050_FIFO_COUNT_H	0x3A
67 #define MPU3050_FIFO_R		0x3C
68 #define MPU3050_USR_CTRL	0x3D
69 #define MPU3050_PWR_MGM		0x3E
70 
71 /* MPU memory bank read options */
72 #define MPU3050_MEM_PRFTCH	BIT(5)
73 #define MPU3050_MEM_USER_BANK	BIT(4)
74 /* Bits 8-11 select memory bank */
75 #define MPU3050_MEM_RAM_BANK_0	0
76 #define MPU3050_MEM_RAM_BANK_1	1
77 #define MPU3050_MEM_RAM_BANK_2	2
78 #define MPU3050_MEM_RAM_BANK_3	3
79 #define MPU3050_MEM_OTP_BANK_0	4
80 
81 #define MPU3050_AXIS_REGS(axis) (MPU3050_XOUT_H + (axis * 2))
82 
83 /* Register bits */
84 
85 /* FIFO Enable */
86 #define MPU3050_FIFO_EN_FOOTER		BIT(0)
87 #define MPU3050_FIFO_EN_AUX_ZOUT	BIT(1)
88 #define MPU3050_FIFO_EN_AUX_YOUT	BIT(2)
89 #define MPU3050_FIFO_EN_AUX_XOUT	BIT(3)
90 #define MPU3050_FIFO_EN_GYRO_ZOUT	BIT(4)
91 #define MPU3050_FIFO_EN_GYRO_YOUT	BIT(5)
92 #define MPU3050_FIFO_EN_GYRO_XOUT	BIT(6)
93 #define MPU3050_FIFO_EN_TEMP_OUT	BIT(7)
94 
95 /*
96  * Digital Low Pass filter (DLPF)
97  * Full Scale (FS)
98  * and Synchronization
99  */
100 #define MPU3050_EXT_SYNC_NONE		0x00
101 #define MPU3050_EXT_SYNC_TEMP		0x20
102 #define MPU3050_EXT_SYNC_GYROX		0x40
103 #define MPU3050_EXT_SYNC_GYROY		0x60
104 #define MPU3050_EXT_SYNC_GYROZ		0x80
105 #define MPU3050_EXT_SYNC_ACCELX	0xA0
106 #define MPU3050_EXT_SYNC_ACCELY	0xC0
107 #define MPU3050_EXT_SYNC_ACCELZ	0xE0
108 #define MPU3050_EXT_SYNC_MASK		0xE0
109 #define MPU3050_EXT_SYNC_SHIFT		5
110 
111 #define MPU3050_FS_250DPS		0x00
112 #define MPU3050_FS_500DPS		0x08
113 #define MPU3050_FS_1000DPS		0x10
114 #define MPU3050_FS_2000DPS		0x18
115 #define MPU3050_FS_MASK			0x18
116 #define MPU3050_FS_SHIFT		3
117 
118 #define MPU3050_DLPF_CFG_256HZ_NOLPF2	0x00
119 #define MPU3050_DLPF_CFG_188HZ		0x01
120 #define MPU3050_DLPF_CFG_98HZ		0x02
121 #define MPU3050_DLPF_CFG_42HZ		0x03
122 #define MPU3050_DLPF_CFG_20HZ		0x04
123 #define MPU3050_DLPF_CFG_10HZ		0x05
124 #define MPU3050_DLPF_CFG_5HZ		0x06
125 #define MPU3050_DLPF_CFG_2100HZ_NOLPF	0x07
126 #define MPU3050_DLPF_CFG_MASK		0x07
127 #define MPU3050_DLPF_CFG_SHIFT		0
128 
129 /* Interrupt config */
130 #define MPU3050_INT_RAW_RDY_EN		BIT(0)
131 #define MPU3050_INT_DMP_DONE_EN		BIT(1)
132 #define MPU3050_INT_MPU_RDY_EN		BIT(2)
133 #define MPU3050_INT_ANYRD_2CLEAR	BIT(4)
134 #define MPU3050_INT_LATCH_EN		BIT(5)
135 #define MPU3050_INT_OPEN		BIT(6)
136 #define MPU3050_INT_ACTL		BIT(7)
137 /* Interrupt status */
138 #define MPU3050_INT_STATUS_RAW_RDY	BIT(0)
139 #define MPU3050_INT_STATUS_DMP_DONE	BIT(1)
140 #define MPU3050_INT_STATUS_MPU_RDY	BIT(2)
141 #define MPU3050_INT_STATUS_FIFO_OVFLW	BIT(7)
142 /* USR_CTRL */
143 #define MPU3050_USR_CTRL_FIFO_EN	BIT(6)
144 #define MPU3050_USR_CTRL_AUX_IF_EN	BIT(5)
145 #define MPU3050_USR_CTRL_AUX_IF_RST	BIT(3)
146 #define MPU3050_USR_CTRL_FIFO_RST	BIT(1)
147 #define MPU3050_USR_CTRL_GYRO_RST	BIT(0)
148 /* PWR_MGM */
149 #define MPU3050_PWR_MGM_PLL_X		0x01
150 #define MPU3050_PWR_MGM_PLL_Y		0x02
151 #define MPU3050_PWR_MGM_PLL_Z		0x03
152 #define MPU3050_PWR_MGM_CLKSEL_MASK	0x07
153 #define MPU3050_PWR_MGM_STBY_ZG		BIT(3)
154 #define MPU3050_PWR_MGM_STBY_YG		BIT(4)
155 #define MPU3050_PWR_MGM_STBY_XG		BIT(5)
156 #define MPU3050_PWR_MGM_SLEEP		BIT(6)
157 #define MPU3050_PWR_MGM_RESET		BIT(7)
158 #define MPU3050_PWR_MGM_MASK		0xff
159 
160 /*
161  * Fullscale precision is (for finest precision) +/- 250 deg/s, so the full
162  * scale is actually 500 deg/s. All 16 bits are then used to cover this scale,
163  * in two's complement.
164  */
165 static unsigned int mpu3050_fs_precision[] = {
166 	IIO_DEGREE_TO_RAD(250),
167 	IIO_DEGREE_TO_RAD(500),
168 	IIO_DEGREE_TO_RAD(1000),
169 	IIO_DEGREE_TO_RAD(2000)
170 };
171 
172 /*
173  * Regulator names
174  */
175 static const char mpu3050_reg_vdd[] = "vdd";
176 static const char mpu3050_reg_vlogic[] = "vlogic";
177 
178 static unsigned int mpu3050_get_freq(struct mpu3050 *mpu3050)
179 {
180 	unsigned int freq;
181 
182 	if (mpu3050->lpf == MPU3050_DLPF_CFG_256HZ_NOLPF2)
183 		freq = 8000;
184 	else
185 		freq = 1000;
186 	freq /= (mpu3050->divisor + 1);
187 
188 	return freq;
189 }
190 
191 static int mpu3050_start_sampling(struct mpu3050 *mpu3050)
192 {
193 	__be16 raw_val[3];
194 	int ret;
195 	int i;
196 
197 	/* Reset */
198 	ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
199 				 MPU3050_PWR_MGM_RESET, MPU3050_PWR_MGM_RESET);
200 	if (ret)
201 		return ret;
202 
203 	/* Turn on the Z-axis PLL */
204 	ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
205 				 MPU3050_PWR_MGM_CLKSEL_MASK,
206 				 MPU3050_PWR_MGM_PLL_Z);
207 	if (ret)
208 		return ret;
209 
210 	/* Write calibration offset registers */
211 	for (i = 0; i < 3; i++)
212 		raw_val[i] = cpu_to_be16(mpu3050->calibration[i]);
213 
214 	ret = regmap_bulk_write(mpu3050->map, MPU3050_X_OFFS_USR_H, raw_val,
215 				sizeof(raw_val));
216 	if (ret)
217 		return ret;
218 
219 	/* Set low pass filter (sample rate), sync and full scale */
220 	ret = regmap_write(mpu3050->map, MPU3050_DLPF_FS_SYNC,
221 			   MPU3050_EXT_SYNC_NONE << MPU3050_EXT_SYNC_SHIFT |
222 			   mpu3050->fullscale << MPU3050_FS_SHIFT |
223 			   mpu3050->lpf << MPU3050_DLPF_CFG_SHIFT);
224 	if (ret)
225 		return ret;
226 
227 	/* Set up sampling frequency */
228 	ret = regmap_write(mpu3050->map, MPU3050_SMPLRT_DIV, mpu3050->divisor);
229 	if (ret)
230 		return ret;
231 
232 	/*
233 	 * Max 50 ms start-up time after setting DLPF_FS_SYNC
234 	 * according to the data sheet, then wait for the next sample
235 	 * at this frequency T = 1000/f ms.
236 	 */
237 	msleep(50 + 1000 / mpu3050_get_freq(mpu3050));
238 
239 	return 0;
240 }
241 
242 static int mpu3050_set_8khz_samplerate(struct mpu3050 *mpu3050)
243 {
244 	int ret;
245 	u8 divisor;
246 	enum mpu3050_lpf lpf;
247 
248 	lpf = mpu3050->lpf;
249 	divisor = mpu3050->divisor;
250 
251 	mpu3050->lpf = LPF_256_HZ_NOLPF; /* 8 kHz base frequency */
252 	mpu3050->divisor = 0; /* Divide by 1 */
253 	ret = mpu3050_start_sampling(mpu3050);
254 
255 	mpu3050->lpf = lpf;
256 	mpu3050->divisor = divisor;
257 
258 	return ret;
259 }
260 
261 static int mpu3050_read_raw(struct iio_dev *indio_dev,
262 			    struct iio_chan_spec const *chan,
263 			    int *val, int *val2,
264 			    long mask)
265 {
266 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
267 	int ret;
268 	__be16 raw_val;
269 
270 	switch (mask) {
271 	case IIO_CHAN_INFO_OFFSET:
272 		switch (chan->type) {
273 		case IIO_TEMP:
274 			/* The temperature scaling is (x+23000)/280 Celsius */
275 			*val = 23000;
276 			return IIO_VAL_INT;
277 		default:
278 			return -EINVAL;
279 		}
280 	case IIO_CHAN_INFO_CALIBBIAS:
281 		switch (chan->type) {
282 		case IIO_ANGL_VEL:
283 			*val = mpu3050->calibration[chan->scan_index-1];
284 			return IIO_VAL_INT;
285 		default:
286 			return -EINVAL;
287 		}
288 	case IIO_CHAN_INFO_SAMP_FREQ:
289 		*val = mpu3050_get_freq(mpu3050);
290 		return IIO_VAL_INT;
291 	case IIO_CHAN_INFO_SCALE:
292 		switch (chan->type) {
293 		case IIO_TEMP:
294 			/* Millidegrees, see about temperature scaling above */
295 			*val = 1000;
296 			*val2 = 280;
297 			return IIO_VAL_FRACTIONAL;
298 		case IIO_ANGL_VEL:
299 			/*
300 			 * Convert to the corresponding full scale in
301 			 * radians. All 16 bits are used with sign to
302 			 * span the available scale: to account for the one
303 			 * missing value if we multiply by 1/S16_MAX, instead
304 			 * multiply with 2/U16_MAX.
305 			 */
306 			*val = mpu3050_fs_precision[mpu3050->fullscale] * 2;
307 			*val2 = U16_MAX;
308 			return IIO_VAL_FRACTIONAL;
309 		default:
310 			return -EINVAL;
311 		}
312 	case IIO_CHAN_INFO_RAW:
313 		/* Resume device */
314 		pm_runtime_get_sync(mpu3050->dev);
315 		mutex_lock(&mpu3050->lock);
316 
317 		ret = mpu3050_set_8khz_samplerate(mpu3050);
318 		if (ret)
319 			goto out_read_raw_unlock;
320 
321 		switch (chan->type) {
322 		case IIO_TEMP:
323 			ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H,
324 					       &raw_val, sizeof(raw_val));
325 			if (ret) {
326 				dev_err(mpu3050->dev,
327 					"error reading temperature\n");
328 				goto out_read_raw_unlock;
329 			}
330 
331 			*val = be16_to_cpu(raw_val);
332 			ret = IIO_VAL_INT;
333 
334 			goto out_read_raw_unlock;
335 		case IIO_ANGL_VEL:
336 			ret = regmap_bulk_read(mpu3050->map,
337 				       MPU3050_AXIS_REGS(chan->scan_index-1),
338 				       &raw_val,
339 				       sizeof(raw_val));
340 			if (ret) {
341 				dev_err(mpu3050->dev,
342 					"error reading axis data\n");
343 				goto out_read_raw_unlock;
344 			}
345 
346 			*val = be16_to_cpu(raw_val);
347 			ret = IIO_VAL_INT;
348 
349 			goto out_read_raw_unlock;
350 		default:
351 			ret = -EINVAL;
352 			goto out_read_raw_unlock;
353 		}
354 	default:
355 		break;
356 	}
357 
358 	return -EINVAL;
359 
360 out_read_raw_unlock:
361 	mutex_unlock(&mpu3050->lock);
362 	pm_runtime_mark_last_busy(mpu3050->dev);
363 	pm_runtime_put_autosuspend(mpu3050->dev);
364 
365 	return ret;
366 }
367 
368 static int mpu3050_write_raw(struct iio_dev *indio_dev,
369 			     const struct iio_chan_spec *chan,
370 			     int val, int val2, long mask)
371 {
372 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
373 	/*
374 	 * Couldn't figure out a way to precalculate these at compile time.
375 	 */
376 	unsigned int fs250 =
377 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[0] * 1000000 * 2,
378 				  U16_MAX);
379 	unsigned int fs500 =
380 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[1] * 1000000 * 2,
381 				  U16_MAX);
382 	unsigned int fs1000 =
383 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[2] * 1000000 * 2,
384 				  U16_MAX);
385 	unsigned int fs2000 =
386 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[3] * 1000000 * 2,
387 				  U16_MAX);
388 
389 	switch (mask) {
390 	case IIO_CHAN_INFO_CALIBBIAS:
391 		if (chan->type != IIO_ANGL_VEL)
392 			return -EINVAL;
393 		mpu3050->calibration[chan->scan_index-1] = val;
394 		return 0;
395 	case IIO_CHAN_INFO_SAMP_FREQ:
396 		/*
397 		 * The max samplerate is 8000 Hz, the minimum
398 		 * 1000 / 256 ~= 4 Hz
399 		 */
400 		if (val < 4 || val > 8000)
401 			return -EINVAL;
402 
403 		/*
404 		 * Above 1000 Hz we must turn off the digital low pass filter
405 		 * so we get a base frequency of 8kHz to the divider
406 		 */
407 		if (val > 1000) {
408 			mpu3050->lpf = LPF_256_HZ_NOLPF;
409 			mpu3050->divisor = DIV_ROUND_CLOSEST(8000, val) - 1;
410 			return 0;
411 		}
412 
413 		mpu3050->lpf = LPF_188_HZ;
414 		mpu3050->divisor = DIV_ROUND_CLOSEST(1000, val) - 1;
415 		return 0;
416 	case IIO_CHAN_INFO_SCALE:
417 		if (chan->type != IIO_ANGL_VEL)
418 			return -EINVAL;
419 		/*
420 		 * We support +/-250, +/-500, +/-1000 and +/2000 deg/s
421 		 * which means we need to round to the closest radians
422 		 * which will be roughly +/-4.3, +/-8.7, +/-17.5, +/-35
423 		 * rad/s. The scale is then for the 16 bits used to cover
424 		 * it 2/(2^16) of that.
425 		 */
426 
427 		/* Just too large, set the max range */
428 		if (val != 0) {
429 			mpu3050->fullscale = FS_2000_DPS;
430 			return 0;
431 		}
432 
433 		/*
434 		 * Now we're dealing with fractions below zero in millirad/s
435 		 * do some integer interpolation and match with the closest
436 		 * fullscale in the table.
437 		 */
438 		if (val2 <= fs250 ||
439 		    val2 < ((fs500 + fs250) / 2))
440 			mpu3050->fullscale = FS_250_DPS;
441 		else if (val2 <= fs500 ||
442 			 val2 < ((fs1000 + fs500) / 2))
443 			mpu3050->fullscale = FS_500_DPS;
444 		else if (val2 <= fs1000 ||
445 			 val2 < ((fs2000 + fs1000) / 2))
446 			mpu3050->fullscale = FS_1000_DPS;
447 		else
448 			/* Catch-all */
449 			mpu3050->fullscale = FS_2000_DPS;
450 		return 0;
451 	default:
452 		break;
453 	}
454 
455 	return -EINVAL;
456 }
457 
458 static irqreturn_t mpu3050_trigger_handler(int irq, void *p)
459 {
460 	const struct iio_poll_func *pf = p;
461 	struct iio_dev *indio_dev = pf->indio_dev;
462 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
463 	int ret;
464 	/*
465 	 * Temperature 1*16 bits
466 	 * Three axes 3*16 bits
467 	 * Timestamp 64 bits (4*16 bits)
468 	 * Sum total 8*16 bits
469 	 */
470 	__be16 hw_values[8];
471 	s64 timestamp;
472 	unsigned int datums_from_fifo = 0;
473 
474 	/*
475 	 * If we're using the hardware trigger, get the precise timestamp from
476 	 * the top half of the threaded IRQ handler. Otherwise get the
477 	 * timestamp here so it will be close in time to the actual values
478 	 * read from the registers.
479 	 */
480 	if (iio_trigger_using_own(indio_dev))
481 		timestamp = mpu3050->hw_timestamp;
482 	else
483 		timestamp = iio_get_time_ns(indio_dev);
484 
485 	mutex_lock(&mpu3050->lock);
486 
487 	/* Using the hardware IRQ trigger? Check the buffer then. */
488 	if (mpu3050->hw_irq_trigger) {
489 		__be16 raw_fifocnt;
490 		u16 fifocnt;
491 		/* X, Y, Z + temperature */
492 		unsigned int bytes_per_datum = 8;
493 		bool fifo_overflow = false;
494 
495 		ret = regmap_bulk_read(mpu3050->map,
496 				       MPU3050_FIFO_COUNT_H,
497 				       &raw_fifocnt,
498 				       sizeof(raw_fifocnt));
499 		if (ret)
500 			goto out_trigger_unlock;
501 		fifocnt = be16_to_cpu(raw_fifocnt);
502 
503 		if (fifocnt == 512) {
504 			dev_info(mpu3050->dev,
505 				 "FIFO overflow! Emptying and resetting FIFO\n");
506 			fifo_overflow = true;
507 			/* Reset and enable the FIFO */
508 			ret = regmap_update_bits(mpu3050->map,
509 						 MPU3050_USR_CTRL,
510 						 MPU3050_USR_CTRL_FIFO_EN |
511 						 MPU3050_USR_CTRL_FIFO_RST,
512 						 MPU3050_USR_CTRL_FIFO_EN |
513 						 MPU3050_USR_CTRL_FIFO_RST);
514 			if (ret) {
515 				dev_info(mpu3050->dev, "error resetting FIFO\n");
516 				goto out_trigger_unlock;
517 			}
518 			mpu3050->pending_fifo_footer = false;
519 		}
520 
521 		if (fifocnt)
522 			dev_dbg(mpu3050->dev,
523 				"%d bytes in the FIFO\n",
524 				fifocnt);
525 
526 		while (!fifo_overflow && fifocnt > bytes_per_datum) {
527 			unsigned int toread;
528 			unsigned int offset;
529 			__be16 fifo_values[5];
530 
531 			/*
532 			 * If there is a FIFO footer in the pipe, first clear
533 			 * that out. This follows the complex algorithm in the
534 			 * datasheet that states that you may never leave the
535 			 * FIFO empty after the first reading: you have to
536 			 * always leave two footer bytes in it. The footer is
537 			 * in practice just two zero bytes.
538 			 */
539 			if (mpu3050->pending_fifo_footer) {
540 				toread = bytes_per_datum + 2;
541 				offset = 0;
542 			} else {
543 				toread = bytes_per_datum;
544 				offset = 1;
545 				/* Put in some dummy value */
546 				fifo_values[0] = cpu_to_be16(0xAAAA);
547 			}
548 
549 			ret = regmap_bulk_read(mpu3050->map,
550 					       MPU3050_FIFO_R,
551 					       &fifo_values[offset],
552 					       toread);
553 
554 			dev_dbg(mpu3050->dev,
555 				"%04x %04x %04x %04x %04x\n",
556 				fifo_values[0],
557 				fifo_values[1],
558 				fifo_values[2],
559 				fifo_values[3],
560 				fifo_values[4]);
561 
562 			/* Index past the footer (fifo_values[0]) and push */
563 			iio_push_to_buffers_with_timestamp(indio_dev,
564 							   &fifo_values[1],
565 							   timestamp);
566 
567 			fifocnt -= toread;
568 			datums_from_fifo++;
569 			mpu3050->pending_fifo_footer = true;
570 
571 			/*
572 			 * If we're emptying the FIFO, just make sure to
573 			 * check if something new appeared.
574 			 */
575 			if (fifocnt < bytes_per_datum) {
576 				ret = regmap_bulk_read(mpu3050->map,
577 						       MPU3050_FIFO_COUNT_H,
578 						       &raw_fifocnt,
579 						       sizeof(raw_fifocnt));
580 				if (ret)
581 					goto out_trigger_unlock;
582 				fifocnt = be16_to_cpu(raw_fifocnt);
583 			}
584 
585 			if (fifocnt < bytes_per_datum)
586 				dev_dbg(mpu3050->dev,
587 					"%d bytes left in the FIFO\n",
588 					fifocnt);
589 
590 			/*
591 			 * At this point, the timestamp that triggered the
592 			 * hardware interrupt is no longer valid for what
593 			 * we are reading (the interrupt likely fired for
594 			 * the value on the top of the FIFO), so set the
595 			 * timestamp to zero and let userspace deal with it.
596 			 */
597 			timestamp = 0;
598 		}
599 	}
600 
601 	/*
602 	 * If we picked some datums from the FIFO that's enough, else
603 	 * fall through and just read from the current value registers.
604 	 * This happens in two cases:
605 	 *
606 	 * - We are using some other trigger (external, like an HRTimer)
607 	 *   than the sensor's own sample generator. In this case the
608 	 *   sensor is just set to the max sampling frequency and we give
609 	 *   the trigger a copy of the latest value every time we get here.
610 	 *
611 	 * - The hardware trigger is active but unused and we actually use
612 	 *   another trigger which calls here with a frequency higher
613 	 *   than what the device provides data. We will then just read
614 	 *   duplicate values directly from the hardware registers.
615 	 */
616 	if (datums_from_fifo) {
617 		dev_dbg(mpu3050->dev,
618 			"read %d datums from the FIFO\n",
619 			datums_from_fifo);
620 		goto out_trigger_unlock;
621 	}
622 
623 	ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H, &hw_values,
624 			       sizeof(hw_values));
625 	if (ret) {
626 		dev_err(mpu3050->dev,
627 			"error reading axis data\n");
628 		goto out_trigger_unlock;
629 	}
630 
631 	iio_push_to_buffers_with_timestamp(indio_dev, hw_values, timestamp);
632 
633 out_trigger_unlock:
634 	mutex_unlock(&mpu3050->lock);
635 	iio_trigger_notify_done(indio_dev->trig);
636 
637 	return IRQ_HANDLED;
638 }
639 
640 static int mpu3050_buffer_preenable(struct iio_dev *indio_dev)
641 {
642 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
643 
644 	pm_runtime_get_sync(mpu3050->dev);
645 
646 	/* Unless we have OUR trigger active, run at full speed */
647 	if (!mpu3050->hw_irq_trigger)
648 		return mpu3050_set_8khz_samplerate(mpu3050);
649 
650 	return 0;
651 }
652 
653 static int mpu3050_buffer_postdisable(struct iio_dev *indio_dev)
654 {
655 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
656 
657 	pm_runtime_mark_last_busy(mpu3050->dev);
658 	pm_runtime_put_autosuspend(mpu3050->dev);
659 
660 	return 0;
661 }
662 
663 static const struct iio_buffer_setup_ops mpu3050_buffer_setup_ops = {
664 	.preenable = mpu3050_buffer_preenable,
665 	.postenable = iio_triggered_buffer_postenable,
666 	.predisable = iio_triggered_buffer_predisable,
667 	.postdisable = mpu3050_buffer_postdisable,
668 };
669 
670 static const struct iio_mount_matrix *
671 mpu3050_get_mount_matrix(const struct iio_dev *indio_dev,
672 			 const struct iio_chan_spec *chan)
673 {
674 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
675 
676 	return &mpu3050->orientation;
677 }
678 
679 static const struct iio_chan_spec_ext_info mpu3050_ext_info[] = {
680 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, mpu3050_get_mount_matrix),
681 	{ },
682 };
683 
684 #define MPU3050_AXIS_CHANNEL(axis, index)				\
685 	{								\
686 		.type = IIO_ANGL_VEL,					\
687 		.modified = 1,						\
688 		.channel2 = IIO_MOD_##axis,				\
689 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
690 			BIT(IIO_CHAN_INFO_CALIBBIAS),			\
691 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
692 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
693 		.ext_info = mpu3050_ext_info,				\
694 		.scan_index = index,					\
695 		.scan_type = {						\
696 			.sign = 's',					\
697 			.realbits = 16,					\
698 			.storagebits = 16,				\
699 			.endianness = IIO_BE,				\
700 		},							\
701 	}
702 
703 static const struct iio_chan_spec mpu3050_channels[] = {
704 	{
705 		.type = IIO_TEMP,
706 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
707 				      BIT(IIO_CHAN_INFO_SCALE) |
708 				      BIT(IIO_CHAN_INFO_OFFSET),
709 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
710 		.scan_index = 0,
711 		.scan_type = {
712 			.sign = 's',
713 			.realbits = 16,
714 			.storagebits = 16,
715 			.endianness = IIO_BE,
716 		},
717 	},
718 	MPU3050_AXIS_CHANNEL(X, 1),
719 	MPU3050_AXIS_CHANNEL(Y, 2),
720 	MPU3050_AXIS_CHANNEL(Z, 3),
721 	IIO_CHAN_SOFT_TIMESTAMP(4),
722 };
723 
724 /* Four channels apart from timestamp, scan mask = 0x0f */
725 static const unsigned long mpu3050_scan_masks[] = { 0xf, 0 };
726 
727 /*
728  * These are just the hardcoded factors resulting from the more elaborate
729  * calculations done with fractions in the scale raw get/set functions.
730  */
731 static IIO_CONST_ATTR(anglevel_scale_available,
732 		      "0.000122070 "
733 		      "0.000274658 "
734 		      "0.000518798 "
735 		      "0.001068115");
736 
737 static struct attribute *mpu3050_attributes[] = {
738 	&iio_const_attr_anglevel_scale_available.dev_attr.attr,
739 	NULL,
740 };
741 
742 static const struct attribute_group mpu3050_attribute_group = {
743 	.attrs = mpu3050_attributes,
744 };
745 
746 static const struct iio_info mpu3050_info = {
747 	.read_raw = mpu3050_read_raw,
748 	.write_raw = mpu3050_write_raw,
749 	.attrs = &mpu3050_attribute_group,
750 };
751 
752 /**
753  * mpu3050_read_mem() - read MPU-3050 internal memory
754  * @mpu3050: device to read from
755  * @bank: target bank
756  * @addr: target address
757  * @len: number of bytes
758  * @buf: the buffer to store the read bytes in
759  */
760 static int mpu3050_read_mem(struct mpu3050 *mpu3050,
761 			    u8 bank,
762 			    u8 addr,
763 			    u8 len,
764 			    u8 *buf)
765 {
766 	int ret;
767 
768 	ret = regmap_write(mpu3050->map,
769 			   MPU3050_BANK_SEL,
770 			   bank);
771 	if (ret)
772 		return ret;
773 
774 	ret = regmap_write(mpu3050->map,
775 			   MPU3050_MEM_START_ADDR,
776 			   addr);
777 	if (ret)
778 		return ret;
779 
780 	return regmap_bulk_read(mpu3050->map,
781 				MPU3050_MEM_R_W,
782 				buf,
783 				len);
784 }
785 
786 static int mpu3050_hw_init(struct mpu3050 *mpu3050)
787 {
788 	int ret;
789 	u8 otp[8];
790 
791 	/* Reset */
792 	ret = regmap_update_bits(mpu3050->map,
793 				 MPU3050_PWR_MGM,
794 				 MPU3050_PWR_MGM_RESET,
795 				 MPU3050_PWR_MGM_RESET);
796 	if (ret)
797 		return ret;
798 
799 	/* Turn on the PLL */
800 	ret = regmap_update_bits(mpu3050->map,
801 				 MPU3050_PWR_MGM,
802 				 MPU3050_PWR_MGM_CLKSEL_MASK,
803 				 MPU3050_PWR_MGM_PLL_Z);
804 	if (ret)
805 		return ret;
806 
807 	/* Disable IRQs */
808 	ret = regmap_write(mpu3050->map,
809 			   MPU3050_INT_CFG,
810 			   0);
811 	if (ret)
812 		return ret;
813 
814 	/* Read out the 8 bytes of OTP (one-time-programmable) memory */
815 	ret = mpu3050_read_mem(mpu3050,
816 			       (MPU3050_MEM_PRFTCH |
817 				MPU3050_MEM_USER_BANK |
818 				MPU3050_MEM_OTP_BANK_0),
819 			       0,
820 			       sizeof(otp),
821 			       otp);
822 	if (ret)
823 		return ret;
824 
825 	/* This is device-unique data so it goes into the entropy pool */
826 	add_device_randomness(otp, sizeof(otp));
827 
828 	dev_info(mpu3050->dev,
829 		 "die ID: %04X, wafer ID: %02X, A lot ID: %04X, "
830 		 "W lot ID: %03X, WP ID: %01X, rev ID: %02X\n",
831 		 /* Die ID, bits 0-12 */
832 		 (otp[1] << 8 | otp[0]) & 0x1fff,
833 		 /* Wafer ID, bits 13-17 */
834 		 ((otp[2] << 8 | otp[1]) & 0x03e0) >> 5,
835 		 /* A lot ID, bits 18-33 */
836 		 ((otp[4] << 16 | otp[3] << 8 | otp[2]) & 0x3fffc) >> 2,
837 		 /* W lot ID, bits 34-45 */
838 		 ((otp[5] << 8 | otp[4]) & 0x3ffc) >> 2,
839 		 /* WP ID, bits 47-49 */
840 		 ((otp[6] << 8 | otp[5]) & 0x0380) >> 7,
841 		 /* rev ID, bits 50-55 */
842 		 otp[6] >> 2);
843 
844 	return 0;
845 }
846 
847 static int mpu3050_power_up(struct mpu3050 *mpu3050)
848 {
849 	int ret;
850 
851 	ret = regulator_bulk_enable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs);
852 	if (ret) {
853 		dev_err(mpu3050->dev, "cannot enable regulators\n");
854 		return ret;
855 	}
856 	/*
857 	 * 20-100 ms start-up time for register read/write according to
858 	 * the datasheet, be on the safe side and wait 200 ms.
859 	 */
860 	msleep(200);
861 
862 	/* Take device out of sleep mode */
863 	ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
864 				 MPU3050_PWR_MGM_SLEEP, 0);
865 	if (ret) {
866 		dev_err(mpu3050->dev, "error setting power mode\n");
867 		return ret;
868 	}
869 	usleep_range(10000, 20000);
870 
871 	return 0;
872 }
873 
874 static int mpu3050_power_down(struct mpu3050 *mpu3050)
875 {
876 	int ret;
877 
878 	/*
879 	 * Put MPU-3050 into sleep mode before cutting regulators.
880 	 * This is important, because we may not be the sole user
881 	 * of the regulator so the power may stay on after this, and
882 	 * then we would be wasting power unless we go to sleep mode
883 	 * first.
884 	 */
885 	ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
886 				 MPU3050_PWR_MGM_SLEEP, MPU3050_PWR_MGM_SLEEP);
887 	if (ret)
888 		dev_err(mpu3050->dev, "error putting to sleep\n");
889 
890 	ret = regulator_bulk_disable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs);
891 	if (ret)
892 		dev_err(mpu3050->dev, "error disabling regulators\n");
893 
894 	return 0;
895 }
896 
897 static irqreturn_t mpu3050_irq_handler(int irq, void *p)
898 {
899 	struct iio_trigger *trig = p;
900 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
901 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
902 
903 	if (!mpu3050->hw_irq_trigger)
904 		return IRQ_NONE;
905 
906 	/* Get the time stamp as close in time as possible */
907 	mpu3050->hw_timestamp = iio_get_time_ns(indio_dev);
908 
909 	return IRQ_WAKE_THREAD;
910 }
911 
912 static irqreturn_t mpu3050_irq_thread(int irq, void *p)
913 {
914 	struct iio_trigger *trig = p;
915 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
916 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
917 	unsigned int val;
918 	int ret;
919 
920 	/* ACK IRQ and check if it was from us */
921 	ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
922 	if (ret) {
923 		dev_err(mpu3050->dev, "error reading IRQ status\n");
924 		return IRQ_HANDLED;
925 	}
926 	if (!(val & MPU3050_INT_STATUS_RAW_RDY))
927 		return IRQ_NONE;
928 
929 	iio_trigger_poll_chained(p);
930 
931 	return IRQ_HANDLED;
932 }
933 
934 /**
935  * mpu3050_drdy_trigger_set_state() - set data ready interrupt state
936  * @trig: trigger instance
937  * @enable: true if trigger should be enabled, false to disable
938  */
939 static int mpu3050_drdy_trigger_set_state(struct iio_trigger *trig,
940 					  bool enable)
941 {
942 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
943 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
944 	unsigned int val;
945 	int ret;
946 
947 	/* Disabling trigger: disable interrupt and return */
948 	if (!enable) {
949 		/* Disable all interrupts */
950 		ret = regmap_write(mpu3050->map,
951 				   MPU3050_INT_CFG,
952 				   0);
953 		if (ret)
954 			dev_err(mpu3050->dev, "error disabling IRQ\n");
955 
956 		/* Clear IRQ flag */
957 		ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
958 		if (ret)
959 			dev_err(mpu3050->dev, "error clearing IRQ status\n");
960 
961 		/* Disable all things in the FIFO and reset it */
962 		ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0);
963 		if (ret)
964 			dev_err(mpu3050->dev, "error disabling FIFO\n");
965 
966 		ret = regmap_write(mpu3050->map, MPU3050_USR_CTRL,
967 				   MPU3050_USR_CTRL_FIFO_RST);
968 		if (ret)
969 			dev_err(mpu3050->dev, "error resetting FIFO\n");
970 
971 		pm_runtime_mark_last_busy(mpu3050->dev);
972 		pm_runtime_put_autosuspend(mpu3050->dev);
973 		mpu3050->hw_irq_trigger = false;
974 
975 		return 0;
976 	} else {
977 		/* Else we're enabling the trigger from this point */
978 		pm_runtime_get_sync(mpu3050->dev);
979 		mpu3050->hw_irq_trigger = true;
980 
981 		/* Disable all things in the FIFO */
982 		ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0);
983 		if (ret)
984 			return ret;
985 
986 		/* Reset and enable the FIFO */
987 		ret = regmap_update_bits(mpu3050->map, MPU3050_USR_CTRL,
988 					 MPU3050_USR_CTRL_FIFO_EN |
989 					 MPU3050_USR_CTRL_FIFO_RST,
990 					 MPU3050_USR_CTRL_FIFO_EN |
991 					 MPU3050_USR_CTRL_FIFO_RST);
992 		if (ret)
993 			return ret;
994 
995 		mpu3050->pending_fifo_footer = false;
996 
997 		/* Turn on the FIFO for temp+X+Y+Z */
998 		ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN,
999 				   MPU3050_FIFO_EN_TEMP_OUT |
1000 				   MPU3050_FIFO_EN_GYRO_XOUT |
1001 				   MPU3050_FIFO_EN_GYRO_YOUT |
1002 				   MPU3050_FIFO_EN_GYRO_ZOUT |
1003 				   MPU3050_FIFO_EN_FOOTER);
1004 		if (ret)
1005 			return ret;
1006 
1007 		/* Configure the sample engine */
1008 		ret = mpu3050_start_sampling(mpu3050);
1009 		if (ret)
1010 			return ret;
1011 
1012 		/* Clear IRQ flag */
1013 		ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
1014 		if (ret)
1015 			dev_err(mpu3050->dev, "error clearing IRQ status\n");
1016 
1017 		/* Give us interrupts whenever there is new data ready */
1018 		val = MPU3050_INT_RAW_RDY_EN;
1019 
1020 		if (mpu3050->irq_actl)
1021 			val |= MPU3050_INT_ACTL;
1022 		if (mpu3050->irq_latch)
1023 			val |= MPU3050_INT_LATCH_EN;
1024 		if (mpu3050->irq_opendrain)
1025 			val |= MPU3050_INT_OPEN;
1026 
1027 		ret = regmap_write(mpu3050->map, MPU3050_INT_CFG, val);
1028 		if (ret)
1029 			return ret;
1030 	}
1031 
1032 	return 0;
1033 }
1034 
1035 static const struct iio_trigger_ops mpu3050_trigger_ops = {
1036 	.set_trigger_state = mpu3050_drdy_trigger_set_state,
1037 };
1038 
1039 static int mpu3050_trigger_probe(struct iio_dev *indio_dev, int irq)
1040 {
1041 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
1042 	unsigned long irq_trig;
1043 	int ret;
1044 
1045 	mpu3050->trig = devm_iio_trigger_alloc(&indio_dev->dev,
1046 					       "%s-dev%d",
1047 					       indio_dev->name,
1048 					       indio_dev->id);
1049 	if (!mpu3050->trig)
1050 		return -ENOMEM;
1051 
1052 	/* Check if IRQ is open drain */
1053 	if (of_property_read_bool(mpu3050->dev->of_node, "drive-open-drain"))
1054 		mpu3050->irq_opendrain = true;
1055 
1056 	irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));
1057 	/*
1058 	 * Configure the interrupt generator hardware to supply whatever
1059 	 * the interrupt is configured for, edges low/high level low/high,
1060 	 * we can provide it all.
1061 	 */
1062 	switch (irq_trig) {
1063 	case IRQF_TRIGGER_RISING:
1064 		dev_info(&indio_dev->dev,
1065 			 "pulse interrupts on the rising edge\n");
1066 		break;
1067 	case IRQF_TRIGGER_FALLING:
1068 		mpu3050->irq_actl = true;
1069 		dev_info(&indio_dev->dev,
1070 			 "pulse interrupts on the falling edge\n");
1071 		break;
1072 	case IRQF_TRIGGER_HIGH:
1073 		mpu3050->irq_latch = true;
1074 		dev_info(&indio_dev->dev,
1075 			 "interrupts active high level\n");
1076 		/*
1077 		 * With level IRQs, we mask the IRQ until it is processed,
1078 		 * but with edge IRQs (pulses) we can queue several interrupts
1079 		 * in the top half.
1080 		 */
1081 		irq_trig |= IRQF_ONESHOT;
1082 		break;
1083 	case IRQF_TRIGGER_LOW:
1084 		mpu3050->irq_latch = true;
1085 		mpu3050->irq_actl = true;
1086 		irq_trig |= IRQF_ONESHOT;
1087 		dev_info(&indio_dev->dev,
1088 			 "interrupts active low level\n");
1089 		break;
1090 	default:
1091 		/* This is the most preferred mode, if possible */
1092 		dev_err(&indio_dev->dev,
1093 			"unsupported IRQ trigger specified (%lx), enforce "
1094 			"rising edge\n", irq_trig);
1095 		irq_trig = IRQF_TRIGGER_RISING;
1096 		break;
1097 	}
1098 
1099 	/* An open drain line can be shared with several devices */
1100 	if (mpu3050->irq_opendrain)
1101 		irq_trig |= IRQF_SHARED;
1102 
1103 	ret = request_threaded_irq(irq,
1104 				   mpu3050_irq_handler,
1105 				   mpu3050_irq_thread,
1106 				   irq_trig,
1107 				   mpu3050->trig->name,
1108 				   mpu3050->trig);
1109 	if (ret) {
1110 		dev_err(mpu3050->dev,
1111 			"can't get IRQ %d, error %d\n", irq, ret);
1112 		return ret;
1113 	}
1114 
1115 	mpu3050->irq = irq;
1116 	mpu3050->trig->dev.parent = mpu3050->dev;
1117 	mpu3050->trig->ops = &mpu3050_trigger_ops;
1118 	iio_trigger_set_drvdata(mpu3050->trig, indio_dev);
1119 
1120 	ret = iio_trigger_register(mpu3050->trig);
1121 	if (ret)
1122 		return ret;
1123 
1124 	indio_dev->trig = iio_trigger_get(mpu3050->trig);
1125 
1126 	return 0;
1127 }
1128 
1129 int mpu3050_common_probe(struct device *dev,
1130 			 struct regmap *map,
1131 			 int irq,
1132 			 const char *name)
1133 {
1134 	struct iio_dev *indio_dev;
1135 	struct mpu3050 *mpu3050;
1136 	unsigned int val;
1137 	int ret;
1138 
1139 	indio_dev = devm_iio_device_alloc(dev, sizeof(*mpu3050));
1140 	if (!indio_dev)
1141 		return -ENOMEM;
1142 	mpu3050 = iio_priv(indio_dev);
1143 
1144 	mpu3050->dev = dev;
1145 	mpu3050->map = map;
1146 	mutex_init(&mpu3050->lock);
1147 	/* Default fullscale: 2000 degrees per second */
1148 	mpu3050->fullscale = FS_2000_DPS;
1149 	/* 1 kHz, divide by 100, default frequency = 10 Hz */
1150 	mpu3050->lpf = MPU3050_DLPF_CFG_188HZ;
1151 	mpu3050->divisor = 99;
1152 
1153 	/* Read the mounting matrix, if present */
1154 	ret = iio_read_mount_matrix(dev, "mount-matrix", &mpu3050->orientation);
1155 	if (ret)
1156 		return ret;
1157 
1158 	/* Fetch and turn on regulators */
1159 	mpu3050->regs[0].supply = mpu3050_reg_vdd;
1160 	mpu3050->regs[1].supply = mpu3050_reg_vlogic;
1161 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(mpu3050->regs),
1162 				      mpu3050->regs);
1163 	if (ret) {
1164 		dev_err(dev, "Cannot get regulators\n");
1165 		return ret;
1166 	}
1167 
1168 	ret = mpu3050_power_up(mpu3050);
1169 	if (ret)
1170 		return ret;
1171 
1172 	ret = regmap_read(map, MPU3050_CHIP_ID_REG, &val);
1173 	if (ret) {
1174 		dev_err(dev, "could not read device ID\n");
1175 		ret = -ENODEV;
1176 
1177 		goto err_power_down;
1178 	}
1179 
1180 	if ((val & MPU3050_CHIP_ID_MASK) != MPU3050_CHIP_ID) {
1181 		dev_err(dev, "unsupported chip id %02x\n",
1182 				(u8)(val & MPU3050_CHIP_ID_MASK));
1183 		ret = -ENODEV;
1184 		goto err_power_down;
1185 	}
1186 
1187 	ret = regmap_read(map, MPU3050_PRODUCT_ID_REG, &val);
1188 	if (ret) {
1189 		dev_err(dev, "could not read device ID\n");
1190 		ret = -ENODEV;
1191 
1192 		goto err_power_down;
1193 	}
1194 	dev_info(dev, "found MPU-3050 part no: %d, version: %d\n",
1195 		 ((val >> 4) & 0xf), (val & 0xf));
1196 
1197 	ret = mpu3050_hw_init(mpu3050);
1198 	if (ret)
1199 		goto err_power_down;
1200 
1201 	indio_dev->dev.parent = dev;
1202 	indio_dev->channels = mpu3050_channels;
1203 	indio_dev->num_channels = ARRAY_SIZE(mpu3050_channels);
1204 	indio_dev->info = &mpu3050_info;
1205 	indio_dev->available_scan_masks = mpu3050_scan_masks;
1206 	indio_dev->modes = INDIO_DIRECT_MODE;
1207 	indio_dev->name = name;
1208 
1209 	ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
1210 					 mpu3050_trigger_handler,
1211 					 &mpu3050_buffer_setup_ops);
1212 	if (ret) {
1213 		dev_err(dev, "triggered buffer setup failed\n");
1214 		goto err_power_down;
1215 	}
1216 
1217 	ret = iio_device_register(indio_dev);
1218 	if (ret) {
1219 		dev_err(dev, "device register failed\n");
1220 		goto err_cleanup_buffer;
1221 	}
1222 
1223 	dev_set_drvdata(dev, indio_dev);
1224 
1225 	/* Check if we have an assigned IRQ to use as trigger */
1226 	if (irq) {
1227 		ret = mpu3050_trigger_probe(indio_dev, irq);
1228 		if (ret)
1229 			dev_err(dev, "failed to register trigger\n");
1230 	}
1231 
1232 	/* Enable runtime PM */
1233 	pm_runtime_get_noresume(dev);
1234 	pm_runtime_set_active(dev);
1235 	pm_runtime_enable(dev);
1236 	/*
1237 	 * Set autosuspend to two orders of magnitude larger than the
1238 	 * start-up time. 100ms start-up time means 10000ms autosuspend,
1239 	 * i.e. 10 seconds.
1240 	 */
1241 	pm_runtime_set_autosuspend_delay(dev, 10000);
1242 	pm_runtime_use_autosuspend(dev);
1243 	pm_runtime_put(dev);
1244 
1245 	return 0;
1246 
1247 err_cleanup_buffer:
1248 	iio_triggered_buffer_cleanup(indio_dev);
1249 err_power_down:
1250 	mpu3050_power_down(mpu3050);
1251 
1252 	return ret;
1253 }
1254 EXPORT_SYMBOL(mpu3050_common_probe);
1255 
1256 int mpu3050_common_remove(struct device *dev)
1257 {
1258 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1259 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
1260 
1261 	pm_runtime_get_sync(dev);
1262 	pm_runtime_put_noidle(dev);
1263 	pm_runtime_disable(dev);
1264 	iio_triggered_buffer_cleanup(indio_dev);
1265 	if (mpu3050->irq)
1266 		free_irq(mpu3050->irq, mpu3050);
1267 	iio_device_unregister(indio_dev);
1268 	mpu3050_power_down(mpu3050);
1269 
1270 	return 0;
1271 }
1272 EXPORT_SYMBOL(mpu3050_common_remove);
1273 
1274 #ifdef CONFIG_PM
1275 static int mpu3050_runtime_suspend(struct device *dev)
1276 {
1277 	return mpu3050_power_down(iio_priv(dev_get_drvdata(dev)));
1278 }
1279 
1280 static int mpu3050_runtime_resume(struct device *dev)
1281 {
1282 	return mpu3050_power_up(iio_priv(dev_get_drvdata(dev)));
1283 }
1284 #endif /* CONFIG_PM */
1285 
1286 const struct dev_pm_ops mpu3050_dev_pm_ops = {
1287 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
1288 				pm_runtime_force_resume)
1289 	SET_RUNTIME_PM_OPS(mpu3050_runtime_suspend,
1290 			   mpu3050_runtime_resume, NULL)
1291 };
1292 EXPORT_SYMBOL(mpu3050_dev_pm_ops);
1293 
1294 MODULE_AUTHOR("Linus Walleij");
1295 MODULE_DESCRIPTION("MPU3050 gyroscope driver");
1296 MODULE_LICENSE("GPL");
1297