xref: /linux/drivers/iio/gyro/mpu3050-core.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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/bitfield.h>
17 #include <linux/bitops.h>
18 #include <linux/delay.h>
19 #include <linux/err.h>
20 #include <linux/iio/buffer.h>
21 #include <linux/iio/iio.h>
22 #include <linux/iio/sysfs.h>
23 #include <linux/iio/trigger.h>
24 #include <linux/iio/trigger_consumer.h>
25 #include <linux/iio/triggered_buffer.h>
26 #include <linux/interrupt.h>
27 #include <linux/module.h>
28 #include <linux/pm_runtime.h>
29 #include <linux/property.h>
30 #include <linux/random.h>
31 #include <linux/slab.h>
32 
33 #include "mpu3050.h"
34 
35 #define MPU3050_CHIP_ID		0x68
36 #define MPU3050_CHIP_ID_MASK	0x7E
37 
38 /*
39  * Register map: anything suffixed *_H is a big-endian high byte and always
40  * followed by the corresponding low byte (*_L) even though these are not
41  * explicitly included in the register definitions.
42  */
43 #define MPU3050_CHIP_ID_REG	0x00
44 #define MPU3050_PRODUCT_ID_REG	0x01
45 #define MPU3050_XG_OFFS_TC	0x05
46 #define MPU3050_YG_OFFS_TC	0x08
47 #define MPU3050_ZG_OFFS_TC	0x0B
48 #define MPU3050_X_OFFS_USR_H	0x0C
49 #define MPU3050_Y_OFFS_USR_H	0x0E
50 #define MPU3050_Z_OFFS_USR_H	0x10
51 #define MPU3050_FIFO_EN		0x12
52 #define MPU3050_AUX_VDDIO	0x13
53 #define MPU3050_SLV_ADDR	0x14
54 #define MPU3050_SMPLRT_DIV	0x15
55 #define MPU3050_DLPF_FS_SYNC	0x16
56 #define MPU3050_INT_CFG		0x17
57 #define MPU3050_AUX_ADDR	0x18
58 #define MPU3050_INT_STATUS	0x1A
59 #define MPU3050_TEMP_H		0x1B
60 #define MPU3050_XOUT_H		0x1D
61 #define MPU3050_YOUT_H		0x1F
62 #define MPU3050_ZOUT_H		0x21
63 #define MPU3050_DMP_CFG1	0x35
64 #define MPU3050_DMP_CFG2	0x36
65 #define MPU3050_BANK_SEL	0x37
66 #define MPU3050_MEM_START_ADDR	0x38
67 #define MPU3050_MEM_R_W		0x39
68 #define MPU3050_FIFO_COUNT_H	0x3A
69 #define MPU3050_FIFO_R		0x3C
70 #define MPU3050_USR_CTRL	0x3D
71 #define MPU3050_PWR_MGM		0x3E
72 
73 /* MPU memory bank read options */
74 #define MPU3050_MEM_PRFTCH	BIT(5)
75 #define MPU3050_MEM_USER_BANK	BIT(4)
76 /* Bits 8-11 select memory bank */
77 #define MPU3050_MEM_RAM_BANK_0	0
78 #define MPU3050_MEM_RAM_BANK_1	1
79 #define MPU3050_MEM_RAM_BANK_2	2
80 #define MPU3050_MEM_RAM_BANK_3	3
81 #define MPU3050_MEM_OTP_BANK_0	4
82 
83 #define MPU3050_AXIS_REGS(axis) (MPU3050_XOUT_H + (axis * 2))
84 
85 /* Register bits */
86 
87 /* FIFO Enable */
88 #define MPU3050_FIFO_EN_FOOTER		BIT(0)
89 #define MPU3050_FIFO_EN_AUX_ZOUT	BIT(1)
90 #define MPU3050_FIFO_EN_AUX_YOUT	BIT(2)
91 #define MPU3050_FIFO_EN_AUX_XOUT	BIT(3)
92 #define MPU3050_FIFO_EN_GYRO_ZOUT	BIT(4)
93 #define MPU3050_FIFO_EN_GYRO_YOUT	BIT(5)
94 #define MPU3050_FIFO_EN_GYRO_XOUT	BIT(6)
95 #define MPU3050_FIFO_EN_TEMP_OUT	BIT(7)
96 
97 /*
98  * Digital Low Pass filter (DLPF)
99  * Full Scale (FS)
100  * and Synchronization
101  */
102 #define MPU3050_EXT_SYNC_NONE		0x00
103 #define MPU3050_EXT_SYNC_TEMP		0x20
104 #define MPU3050_EXT_SYNC_GYROX		0x40
105 #define MPU3050_EXT_SYNC_GYROY		0x60
106 #define MPU3050_EXT_SYNC_GYROZ		0x80
107 #define MPU3050_EXT_SYNC_ACCELX	0xA0
108 #define MPU3050_EXT_SYNC_ACCELY	0xC0
109 #define MPU3050_EXT_SYNC_ACCELZ	0xE0
110 #define MPU3050_EXT_SYNC_MASK		0xE0
111 #define MPU3050_EXT_SYNC_SHIFT		5
112 
113 #define MPU3050_FS_250DPS		0x00
114 #define MPU3050_FS_500DPS		0x08
115 #define MPU3050_FS_1000DPS		0x10
116 #define MPU3050_FS_2000DPS		0x18
117 #define MPU3050_FS_MASK			0x18
118 #define MPU3050_FS_SHIFT		3
119 
120 #define MPU3050_DLPF_CFG_256HZ_NOLPF2	0x00
121 #define MPU3050_DLPF_CFG_188HZ		0x01
122 #define MPU3050_DLPF_CFG_98HZ		0x02
123 #define MPU3050_DLPF_CFG_42HZ		0x03
124 #define MPU3050_DLPF_CFG_20HZ		0x04
125 #define MPU3050_DLPF_CFG_10HZ		0x05
126 #define MPU3050_DLPF_CFG_5HZ		0x06
127 #define MPU3050_DLPF_CFG_2100HZ_NOLPF	0x07
128 #define MPU3050_DLPF_CFG_MASK		0x07
129 #define MPU3050_DLPF_CFG_SHIFT		0
130 
131 /* Interrupt config */
132 #define MPU3050_INT_RAW_RDY_EN		BIT(0)
133 #define MPU3050_INT_DMP_DONE_EN		BIT(1)
134 #define MPU3050_INT_MPU_RDY_EN		BIT(2)
135 #define MPU3050_INT_ANYRD_2CLEAR	BIT(4)
136 #define MPU3050_INT_LATCH_EN		BIT(5)
137 #define MPU3050_INT_OPEN		BIT(6)
138 #define MPU3050_INT_ACTL		BIT(7)
139 /* Interrupt status */
140 #define MPU3050_INT_STATUS_RAW_RDY	BIT(0)
141 #define MPU3050_INT_STATUS_DMP_DONE	BIT(1)
142 #define MPU3050_INT_STATUS_MPU_RDY	BIT(2)
143 #define MPU3050_INT_STATUS_FIFO_OVFLW	BIT(7)
144 /* USR_CTRL */
145 #define MPU3050_USR_CTRL_FIFO_EN	BIT(6)
146 #define MPU3050_USR_CTRL_AUX_IF_EN	BIT(5)
147 #define MPU3050_USR_CTRL_AUX_IF_RST	BIT(3)
148 #define MPU3050_USR_CTRL_FIFO_RST	BIT(1)
149 #define MPU3050_USR_CTRL_GYRO_RST	BIT(0)
150 /* PWR_MGM */
151 #define MPU3050_PWR_MGM_PLL_X		0x01
152 #define MPU3050_PWR_MGM_PLL_Y		0x02
153 #define MPU3050_PWR_MGM_PLL_Z		0x03
154 #define MPU3050_PWR_MGM_CLKSEL_MASK	0x07
155 #define MPU3050_PWR_MGM_STBY_ZG		BIT(3)
156 #define MPU3050_PWR_MGM_STBY_YG		BIT(4)
157 #define MPU3050_PWR_MGM_STBY_XG		BIT(5)
158 #define MPU3050_PWR_MGM_SLEEP		BIT(6)
159 #define MPU3050_PWR_MGM_RESET		BIT(7)
160 #define MPU3050_PWR_MGM_MASK		0xff
161 
162 /*
163  * Fullscale precision is (for finest precision) +/- 250 deg/s, so the full
164  * scale is actually 500 deg/s. All 16 bits are then used to cover this scale,
165  * in two's complement.
166  */
167 static unsigned int mpu3050_fs_precision[] = {
168 	IIO_DEGREE_TO_RAD(250),
169 	IIO_DEGREE_TO_RAD(500),
170 	IIO_DEGREE_TO_RAD(1000),
171 	IIO_DEGREE_TO_RAD(2000)
172 };
173 
174 /*
175  * Regulator names
176  */
177 static const char mpu3050_reg_vdd[] = "vdd";
178 static const char mpu3050_reg_vlogic[] = "vlogic";
179 
180 static unsigned int mpu3050_get_freq(struct mpu3050 *mpu3050)
181 {
182 	unsigned int freq;
183 
184 	if (mpu3050->lpf == MPU3050_DLPF_CFG_256HZ_NOLPF2)
185 		freq = 8000;
186 	else
187 		freq = 1000;
188 	freq /= (mpu3050->divisor + 1);
189 
190 	return freq;
191 }
192 
193 static int mpu3050_start_sampling(struct mpu3050 *mpu3050)
194 {
195 	__be16 raw_val[3];
196 	int ret;
197 	int i;
198 
199 	/* Reset */
200 	ret = regmap_set_bits(mpu3050->map, MPU3050_PWR_MGM,
201 			      MPU3050_PWR_MGM_RESET);
202 	if (ret)
203 		return ret;
204 
205 	/* Turn on the Z-axis PLL */
206 	ret = regmap_update_bits(mpu3050->map, MPU3050_PWR_MGM,
207 				 MPU3050_PWR_MGM_CLKSEL_MASK,
208 				 MPU3050_PWR_MGM_PLL_Z);
209 	if (ret)
210 		return ret;
211 
212 	/* Write calibration offset registers */
213 	for (i = 0; i < 3; i++)
214 		raw_val[i] = cpu_to_be16(mpu3050->calibration[i]);
215 
216 	ret = regmap_bulk_write(mpu3050->map, MPU3050_X_OFFS_USR_H, raw_val,
217 				sizeof(raw_val));
218 	if (ret)
219 		return ret;
220 
221 	/* Set low pass filter (sample rate), sync and full scale */
222 	ret = regmap_write(mpu3050->map, MPU3050_DLPF_FS_SYNC,
223 			   MPU3050_EXT_SYNC_NONE << MPU3050_EXT_SYNC_SHIFT |
224 			   mpu3050->fullscale << MPU3050_FS_SHIFT |
225 			   mpu3050->lpf << MPU3050_DLPF_CFG_SHIFT);
226 	if (ret)
227 		return ret;
228 
229 	/* Set up sampling frequency */
230 	ret = regmap_write(mpu3050->map, MPU3050_SMPLRT_DIV, mpu3050->divisor);
231 	if (ret)
232 		return ret;
233 
234 	/*
235 	 * Max 50 ms start-up time after setting DLPF_FS_SYNC
236 	 * according to the data sheet, then wait for the next sample
237 	 * at this frequency T = 1000/f ms.
238 	 */
239 	msleep(50 + 1000 / mpu3050_get_freq(mpu3050));
240 
241 	return 0;
242 }
243 
244 static int mpu3050_set_8khz_samplerate(struct mpu3050 *mpu3050)
245 {
246 	int ret;
247 	u8 divisor;
248 	enum mpu3050_lpf lpf;
249 
250 	lpf = mpu3050->lpf;
251 	divisor = mpu3050->divisor;
252 
253 	mpu3050->lpf = LPF_256_HZ_NOLPF; /* 8 kHz base frequency */
254 	mpu3050->divisor = 0; /* Divide by 1 */
255 	ret = mpu3050_start_sampling(mpu3050);
256 
257 	mpu3050->lpf = lpf;
258 	mpu3050->divisor = divisor;
259 
260 	return ret;
261 }
262 
263 static int mpu3050_read_raw(struct iio_dev *indio_dev,
264 			    struct iio_chan_spec const *chan,
265 			    int *val, int *val2,
266 			    long mask)
267 {
268 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
269 	int ret;
270 	__be16 raw_val;
271 
272 	switch (mask) {
273 	case IIO_CHAN_INFO_OFFSET:
274 		switch (chan->type) {
275 		case IIO_TEMP:
276 			/*
277 			 * The temperature scaling is (x+23000)/280 Celsius
278 			 * for the "best fit straight line" temperature range
279 			 * of -30C..85C.  The 23000 includes room temperature
280 			 * offset of +35C, 280 is the precision scale and x is
281 			 * the 16-bit signed integer reported by hardware.
282 			 *
283 			 * Temperature value itself represents temperature of
284 			 * the sensor die.
285 			 */
286 			*val = 23000;
287 			return IIO_VAL_INT;
288 		default:
289 			return -EINVAL;
290 		}
291 	case IIO_CHAN_INFO_CALIBBIAS:
292 		switch (chan->type) {
293 		case IIO_ANGL_VEL:
294 			*val = mpu3050->calibration[chan->scan_index-1];
295 			return IIO_VAL_INT;
296 		default:
297 			return -EINVAL;
298 		}
299 	case IIO_CHAN_INFO_SAMP_FREQ:
300 		*val = mpu3050_get_freq(mpu3050);
301 		return IIO_VAL_INT;
302 	case IIO_CHAN_INFO_SCALE:
303 		switch (chan->type) {
304 		case IIO_TEMP:
305 			/* Millidegrees, see about temperature scaling above */
306 			*val = 1000;
307 			*val2 = 280;
308 			return IIO_VAL_FRACTIONAL;
309 		case IIO_ANGL_VEL:
310 			/*
311 			 * Convert to the corresponding full scale in
312 			 * radians. All 16 bits are used with sign to
313 			 * span the available scale: to account for the one
314 			 * missing value if we multiply by 1/S16_MAX, instead
315 			 * multiply with 2/U16_MAX.
316 			 */
317 			*val = mpu3050_fs_precision[mpu3050->fullscale] * 2;
318 			*val2 = U16_MAX;
319 			return IIO_VAL_FRACTIONAL;
320 		default:
321 			return -EINVAL;
322 		}
323 	case IIO_CHAN_INFO_RAW:
324 		/* Resume device */
325 		pm_runtime_get_sync(mpu3050->dev);
326 		mutex_lock(&mpu3050->lock);
327 
328 		ret = mpu3050_set_8khz_samplerate(mpu3050);
329 		if (ret)
330 			goto out_read_raw_unlock;
331 
332 		switch (chan->type) {
333 		case IIO_TEMP:
334 			ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H,
335 					       &raw_val, sizeof(raw_val));
336 			if (ret) {
337 				dev_err(mpu3050->dev,
338 					"error reading temperature\n");
339 				goto out_read_raw_unlock;
340 			}
341 
342 			*val = (s16)be16_to_cpu(raw_val);
343 			ret = IIO_VAL_INT;
344 
345 			goto out_read_raw_unlock;
346 		case IIO_ANGL_VEL:
347 			ret = regmap_bulk_read(mpu3050->map,
348 				       MPU3050_AXIS_REGS(chan->scan_index-1),
349 				       &raw_val,
350 				       sizeof(raw_val));
351 			if (ret) {
352 				dev_err(mpu3050->dev,
353 					"error reading axis data\n");
354 				goto out_read_raw_unlock;
355 			}
356 
357 			*val = be16_to_cpu(raw_val);
358 			ret = IIO_VAL_INT;
359 
360 			goto out_read_raw_unlock;
361 		default:
362 			ret = -EINVAL;
363 			goto out_read_raw_unlock;
364 		}
365 	default:
366 		break;
367 	}
368 
369 	return -EINVAL;
370 
371 out_read_raw_unlock:
372 	mutex_unlock(&mpu3050->lock);
373 	pm_runtime_mark_last_busy(mpu3050->dev);
374 	pm_runtime_put_autosuspend(mpu3050->dev);
375 
376 	return ret;
377 }
378 
379 static int mpu3050_write_raw(struct iio_dev *indio_dev,
380 			     const struct iio_chan_spec *chan,
381 			     int val, int val2, long mask)
382 {
383 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
384 	/*
385 	 * Couldn't figure out a way to precalculate these at compile time.
386 	 */
387 	unsigned int fs250 =
388 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[0] * 1000000 * 2,
389 				  U16_MAX);
390 	unsigned int fs500 =
391 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[1] * 1000000 * 2,
392 				  U16_MAX);
393 	unsigned int fs1000 =
394 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[2] * 1000000 * 2,
395 				  U16_MAX);
396 	unsigned int fs2000 =
397 		DIV_ROUND_CLOSEST(mpu3050_fs_precision[3] * 1000000 * 2,
398 				  U16_MAX);
399 
400 	switch (mask) {
401 	case IIO_CHAN_INFO_CALIBBIAS:
402 		if (chan->type != IIO_ANGL_VEL)
403 			return -EINVAL;
404 		mpu3050->calibration[chan->scan_index-1] = val;
405 		return 0;
406 	case IIO_CHAN_INFO_SAMP_FREQ:
407 		/*
408 		 * The max samplerate is 8000 Hz, the minimum
409 		 * 1000 / 256 ~= 4 Hz
410 		 */
411 		if (val < 4 || val > 8000)
412 			return -EINVAL;
413 
414 		/*
415 		 * Above 1000 Hz we must turn off the digital low pass filter
416 		 * so we get a base frequency of 8kHz to the divider
417 		 */
418 		if (val > 1000) {
419 			mpu3050->lpf = LPF_256_HZ_NOLPF;
420 			mpu3050->divisor = DIV_ROUND_CLOSEST(8000, val) - 1;
421 			return 0;
422 		}
423 
424 		mpu3050->lpf = LPF_188_HZ;
425 		mpu3050->divisor = DIV_ROUND_CLOSEST(1000, val) - 1;
426 		return 0;
427 	case IIO_CHAN_INFO_SCALE:
428 		if (chan->type != IIO_ANGL_VEL)
429 			return -EINVAL;
430 		/*
431 		 * We support +/-250, +/-500, +/-1000 and +/2000 deg/s
432 		 * which means we need to round to the closest radians
433 		 * which will be roughly +/-4.3, +/-8.7, +/-17.5, +/-35
434 		 * rad/s. The scale is then for the 16 bits used to cover
435 		 * it 2/(2^16) of that.
436 		 */
437 
438 		/* Just too large, set the max range */
439 		if (val != 0) {
440 			mpu3050->fullscale = FS_2000_DPS;
441 			return 0;
442 		}
443 
444 		/*
445 		 * Now we're dealing with fractions below zero in millirad/s
446 		 * do some integer interpolation and match with the closest
447 		 * fullscale in the table.
448 		 */
449 		if (val2 <= fs250 ||
450 		    val2 < ((fs500 + fs250) / 2))
451 			mpu3050->fullscale = FS_250_DPS;
452 		else if (val2 <= fs500 ||
453 			 val2 < ((fs1000 + fs500) / 2))
454 			mpu3050->fullscale = FS_500_DPS;
455 		else if (val2 <= fs1000 ||
456 			 val2 < ((fs2000 + fs1000) / 2))
457 			mpu3050->fullscale = FS_1000_DPS;
458 		else
459 			/* Catch-all */
460 			mpu3050->fullscale = FS_2000_DPS;
461 		return 0;
462 	default:
463 		break;
464 	}
465 
466 	return -EINVAL;
467 }
468 
469 static irqreturn_t mpu3050_trigger_handler(int irq, void *p)
470 {
471 	const struct iio_poll_func *pf = p;
472 	struct iio_dev *indio_dev = pf->indio_dev;
473 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
474 	int ret;
475 	struct {
476 		__be16 chans[4];
477 		s64 timestamp __aligned(8);
478 	} scan;
479 	s64 timestamp;
480 	unsigned int datums_from_fifo = 0;
481 
482 	/*
483 	 * If we're using the hardware trigger, get the precise timestamp from
484 	 * the top half of the threaded IRQ handler. Otherwise get the
485 	 * timestamp here so it will be close in time to the actual values
486 	 * read from the registers.
487 	 */
488 	if (iio_trigger_using_own(indio_dev))
489 		timestamp = mpu3050->hw_timestamp;
490 	else
491 		timestamp = iio_get_time_ns(indio_dev);
492 
493 	mutex_lock(&mpu3050->lock);
494 
495 	/* Using the hardware IRQ trigger? Check the buffer then. */
496 	if (mpu3050->hw_irq_trigger) {
497 		__be16 raw_fifocnt;
498 		u16 fifocnt;
499 		/* X, Y, Z + temperature */
500 		unsigned int bytes_per_datum = 8;
501 		bool fifo_overflow = false;
502 
503 		ret = regmap_bulk_read(mpu3050->map,
504 				       MPU3050_FIFO_COUNT_H,
505 				       &raw_fifocnt,
506 				       sizeof(raw_fifocnt));
507 		if (ret)
508 			goto out_trigger_unlock;
509 		fifocnt = be16_to_cpu(raw_fifocnt);
510 
511 		if (fifocnt == 512) {
512 			dev_info(mpu3050->dev,
513 				 "FIFO overflow! Emptying and resetting FIFO\n");
514 			fifo_overflow = true;
515 			/* Reset and enable the FIFO */
516 			ret = regmap_set_bits(mpu3050->map, MPU3050_USR_CTRL,
517 					      MPU3050_USR_CTRL_FIFO_EN |
518 					      MPU3050_USR_CTRL_FIFO_RST);
519 			if (ret) {
520 				dev_info(mpu3050->dev, "error resetting FIFO\n");
521 				goto out_trigger_unlock;
522 			}
523 			mpu3050->pending_fifo_footer = false;
524 		}
525 
526 		if (fifocnt)
527 			dev_dbg(mpu3050->dev,
528 				"%d bytes in the FIFO\n",
529 				fifocnt);
530 
531 		while (!fifo_overflow && fifocnt > bytes_per_datum) {
532 			unsigned int toread;
533 			unsigned int offset;
534 			__be16 fifo_values[5];
535 
536 			/*
537 			 * If there is a FIFO footer in the pipe, first clear
538 			 * that out. This follows the complex algorithm in the
539 			 * datasheet that states that you may never leave the
540 			 * FIFO empty after the first reading: you have to
541 			 * always leave two footer bytes in it. The footer is
542 			 * in practice just two zero bytes.
543 			 */
544 			if (mpu3050->pending_fifo_footer) {
545 				toread = bytes_per_datum + 2;
546 				offset = 0;
547 			} else {
548 				toread = bytes_per_datum;
549 				offset = 1;
550 				/* Put in some dummy value */
551 				fifo_values[0] = cpu_to_be16(0xAAAA);
552 			}
553 
554 			ret = regmap_bulk_read(mpu3050->map,
555 					       MPU3050_FIFO_R,
556 					       &fifo_values[offset],
557 					       toread);
558 			if (ret)
559 				goto out_trigger_unlock;
560 
561 			dev_dbg(mpu3050->dev,
562 				"%04x %04x %04x %04x %04x\n",
563 				fifo_values[0],
564 				fifo_values[1],
565 				fifo_values[2],
566 				fifo_values[3],
567 				fifo_values[4]);
568 
569 			/* Index past the footer (fifo_values[0]) and push */
570 			iio_push_to_buffers_with_ts_unaligned(indio_dev,
571 							      &fifo_values[1],
572 							      sizeof(__be16) * 4,
573 							      timestamp);
574 
575 			fifocnt -= toread;
576 			datums_from_fifo++;
577 			mpu3050->pending_fifo_footer = true;
578 
579 			/*
580 			 * If we're emptying the FIFO, just make sure to
581 			 * check if something new appeared.
582 			 */
583 			if (fifocnt < bytes_per_datum) {
584 				ret = regmap_bulk_read(mpu3050->map,
585 						       MPU3050_FIFO_COUNT_H,
586 						       &raw_fifocnt,
587 						       sizeof(raw_fifocnt));
588 				if (ret)
589 					goto out_trigger_unlock;
590 				fifocnt = be16_to_cpu(raw_fifocnt);
591 			}
592 
593 			if (fifocnt < bytes_per_datum)
594 				dev_dbg(mpu3050->dev,
595 					"%d bytes left in the FIFO\n",
596 					fifocnt);
597 
598 			/*
599 			 * At this point, the timestamp that triggered the
600 			 * hardware interrupt is no longer valid for what
601 			 * we are reading (the interrupt likely fired for
602 			 * the value on the top of the FIFO), so set the
603 			 * timestamp to zero and let userspace deal with it.
604 			 */
605 			timestamp = 0;
606 		}
607 	}
608 
609 	/*
610 	 * If we picked some datums from the FIFO that's enough, else
611 	 * fall through and just read from the current value registers.
612 	 * This happens in two cases:
613 	 *
614 	 * - We are using some other trigger (external, like an HRTimer)
615 	 *   than the sensor's own sample generator. In this case the
616 	 *   sensor is just set to the max sampling frequency and we give
617 	 *   the trigger a copy of the latest value every time we get here.
618 	 *
619 	 * - The hardware trigger is active but unused and we actually use
620 	 *   another trigger which calls here with a frequency higher
621 	 *   than what the device provides data. We will then just read
622 	 *   duplicate values directly from the hardware registers.
623 	 */
624 	if (datums_from_fifo) {
625 		dev_dbg(mpu3050->dev,
626 			"read %d datums from the FIFO\n",
627 			datums_from_fifo);
628 		goto out_trigger_unlock;
629 	}
630 
631 	ret = regmap_bulk_read(mpu3050->map, MPU3050_TEMP_H, scan.chans,
632 			       sizeof(scan.chans));
633 	if (ret) {
634 		dev_err(mpu3050->dev,
635 			"error reading axis data\n");
636 		goto out_trigger_unlock;
637 	}
638 
639 	iio_push_to_buffers_with_timestamp(indio_dev, &scan, timestamp);
640 
641 out_trigger_unlock:
642 	mutex_unlock(&mpu3050->lock);
643 	iio_trigger_notify_done(indio_dev->trig);
644 
645 	return IRQ_HANDLED;
646 }
647 
648 static int mpu3050_buffer_preenable(struct iio_dev *indio_dev)
649 {
650 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
651 
652 	pm_runtime_get_sync(mpu3050->dev);
653 
654 	/* Unless we have OUR trigger active, run at full speed */
655 	if (!mpu3050->hw_irq_trigger)
656 		return mpu3050_set_8khz_samplerate(mpu3050);
657 
658 	return 0;
659 }
660 
661 static int mpu3050_buffer_postdisable(struct iio_dev *indio_dev)
662 {
663 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
664 
665 	pm_runtime_mark_last_busy(mpu3050->dev);
666 	pm_runtime_put_autosuspend(mpu3050->dev);
667 
668 	return 0;
669 }
670 
671 static const struct iio_buffer_setup_ops mpu3050_buffer_setup_ops = {
672 	.preenable = mpu3050_buffer_preenable,
673 	.postdisable = mpu3050_buffer_postdisable,
674 };
675 
676 static const struct iio_mount_matrix *
677 mpu3050_get_mount_matrix(const struct iio_dev *indio_dev,
678 			 const struct iio_chan_spec *chan)
679 {
680 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
681 
682 	return &mpu3050->orientation;
683 }
684 
685 static const struct iio_chan_spec_ext_info mpu3050_ext_info[] = {
686 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, mpu3050_get_mount_matrix),
687 	{ },
688 };
689 
690 #define MPU3050_AXIS_CHANNEL(axis, index)				\
691 	{								\
692 		.type = IIO_ANGL_VEL,					\
693 		.modified = 1,						\
694 		.channel2 = IIO_MOD_##axis,				\
695 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		\
696 			BIT(IIO_CHAN_INFO_CALIBBIAS),			\
697 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
698 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),\
699 		.ext_info = mpu3050_ext_info,				\
700 		.scan_index = index,					\
701 		.scan_type = {						\
702 			.sign = 's',					\
703 			.realbits = 16,					\
704 			.storagebits = 16,				\
705 			.endianness = IIO_BE,				\
706 		},							\
707 	}
708 
709 static const struct iio_chan_spec mpu3050_channels[] = {
710 	{
711 		.type = IIO_TEMP,
712 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
713 				      BIT(IIO_CHAN_INFO_SCALE) |
714 				      BIT(IIO_CHAN_INFO_OFFSET),
715 		.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
716 		.scan_index = 0,
717 		.scan_type = {
718 			.sign = 's',
719 			.realbits = 16,
720 			.storagebits = 16,
721 			.endianness = IIO_BE,
722 		},
723 	},
724 	MPU3050_AXIS_CHANNEL(X, 1),
725 	MPU3050_AXIS_CHANNEL(Y, 2),
726 	MPU3050_AXIS_CHANNEL(Z, 3),
727 	IIO_CHAN_SOFT_TIMESTAMP(4),
728 };
729 
730 /* Four channels apart from timestamp, scan mask = 0x0f */
731 static const unsigned long mpu3050_scan_masks[] = { 0xf, 0 };
732 
733 /*
734  * These are just the hardcoded factors resulting from the more elaborate
735  * calculations done with fractions in the scale raw get/set functions.
736  */
737 static IIO_CONST_ATTR(anglevel_scale_available,
738 		      "0.000122070 "
739 		      "0.000274658 "
740 		      "0.000518798 "
741 		      "0.001068115");
742 
743 static struct attribute *mpu3050_attributes[] = {
744 	&iio_const_attr_anglevel_scale_available.dev_attr.attr,
745 	NULL,
746 };
747 
748 static const struct attribute_group mpu3050_attribute_group = {
749 	.attrs = mpu3050_attributes,
750 };
751 
752 static const struct iio_info mpu3050_info = {
753 	.read_raw = mpu3050_read_raw,
754 	.write_raw = mpu3050_write_raw,
755 	.attrs = &mpu3050_attribute_group,
756 };
757 
758 /**
759  * mpu3050_read_mem() - read MPU-3050 internal memory
760  * @mpu3050: device to read from
761  * @bank: target bank
762  * @addr: target address
763  * @len: number of bytes
764  * @buf: the buffer to store the read bytes in
765  */
766 static int mpu3050_read_mem(struct mpu3050 *mpu3050,
767 			    u8 bank,
768 			    u8 addr,
769 			    u8 len,
770 			    u8 *buf)
771 {
772 	int ret;
773 
774 	ret = regmap_write(mpu3050->map,
775 			   MPU3050_BANK_SEL,
776 			   bank);
777 	if (ret)
778 		return ret;
779 
780 	ret = regmap_write(mpu3050->map,
781 			   MPU3050_MEM_START_ADDR,
782 			   addr);
783 	if (ret)
784 		return ret;
785 
786 	return regmap_bulk_read(mpu3050->map,
787 				MPU3050_MEM_R_W,
788 				buf,
789 				len);
790 }
791 
792 static int mpu3050_hw_init(struct mpu3050 *mpu3050)
793 {
794 	int ret;
795 	__le64 otp_le;
796 	u64 otp;
797 
798 	/* Reset */
799 	ret = regmap_set_bits(mpu3050->map, MPU3050_PWR_MGM,
800 			      MPU3050_PWR_MGM_RESET);
801 	if (ret)
802 		return ret;
803 
804 	/* Turn on the PLL */
805 	ret = regmap_update_bits(mpu3050->map,
806 				 MPU3050_PWR_MGM,
807 				 MPU3050_PWR_MGM_CLKSEL_MASK,
808 				 MPU3050_PWR_MGM_PLL_Z);
809 	if (ret)
810 		return ret;
811 
812 	/* Disable IRQs */
813 	ret = regmap_write(mpu3050->map,
814 			   MPU3050_INT_CFG,
815 			   0);
816 	if (ret)
817 		return ret;
818 
819 	/* Read out the 8 bytes of OTP (one-time-programmable) memory */
820 	ret = mpu3050_read_mem(mpu3050,
821 			       (MPU3050_MEM_PRFTCH |
822 				MPU3050_MEM_USER_BANK |
823 				MPU3050_MEM_OTP_BANK_0),
824 			       0,
825 			       sizeof(otp_le),
826 			       (u8 *)&otp_le);
827 	if (ret)
828 		return ret;
829 
830 	/* This is device-unique data so it goes into the entropy pool */
831 	add_device_randomness(&otp_le, sizeof(otp_le));
832 
833 	otp = le64_to_cpu(otp_le);
834 
835 	dev_info(mpu3050->dev,
836 		 "die ID: %04llX, wafer ID: %02llX, A lot ID: %04llX, "
837 		 "W lot ID: %03llX, WP ID: %01llX, rev ID: %02llX\n",
838 		 /* Die ID, bits 0-12 */
839 		 FIELD_GET(GENMASK_ULL(12, 0), otp),
840 		 /* Wafer ID, bits 13-17 */
841 		 FIELD_GET(GENMASK_ULL(17, 13), otp),
842 		 /* A lot ID, bits 18-33 */
843 		 FIELD_GET(GENMASK_ULL(33, 18), otp),
844 		 /* W lot ID, bits 34-45 */
845 		 FIELD_GET(GENMASK_ULL(45, 34), otp),
846 		 /* WP ID, bits 47-49 */
847 		 FIELD_GET(GENMASK_ULL(49, 47), otp),
848 		 /* rev ID, bits 50-55 */
849 		 FIELD_GET(GENMASK_ULL(55, 50), otp));
850 
851 	return 0;
852 }
853 
854 static int mpu3050_power_up(struct mpu3050 *mpu3050)
855 {
856 	int ret;
857 
858 	ret = regulator_bulk_enable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs);
859 	if (ret) {
860 		dev_err(mpu3050->dev, "cannot enable regulators\n");
861 		return ret;
862 	}
863 	/*
864 	 * 20-100 ms start-up time for register read/write according to
865 	 * the datasheet, be on the safe side and wait 200 ms.
866 	 */
867 	msleep(200);
868 
869 	/* Take device out of sleep mode */
870 	ret = regmap_clear_bits(mpu3050->map, MPU3050_PWR_MGM,
871 				MPU3050_PWR_MGM_SLEEP);
872 	if (ret) {
873 		regulator_bulk_disable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs);
874 		dev_err(mpu3050->dev, "error setting power mode\n");
875 		return ret;
876 	}
877 	usleep_range(10000, 20000);
878 
879 	return 0;
880 }
881 
882 static int mpu3050_power_down(struct mpu3050 *mpu3050)
883 {
884 	int ret;
885 
886 	/*
887 	 * Put MPU-3050 into sleep mode before cutting regulators.
888 	 * This is important, because we may not be the sole user
889 	 * of the regulator so the power may stay on after this, and
890 	 * then we would be wasting power unless we go to sleep mode
891 	 * first.
892 	 */
893 	ret = regmap_set_bits(mpu3050->map, MPU3050_PWR_MGM,
894 			      MPU3050_PWR_MGM_SLEEP);
895 	if (ret)
896 		dev_err(mpu3050->dev, "error putting to sleep\n");
897 
898 	ret = regulator_bulk_disable(ARRAY_SIZE(mpu3050->regs), mpu3050->regs);
899 	if (ret)
900 		dev_err(mpu3050->dev, "error disabling regulators\n");
901 
902 	return 0;
903 }
904 
905 static irqreturn_t mpu3050_irq_handler(int irq, void *p)
906 {
907 	struct iio_trigger *trig = p;
908 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
909 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
910 
911 	if (!mpu3050->hw_irq_trigger)
912 		return IRQ_NONE;
913 
914 	/* Get the time stamp as close in time as possible */
915 	mpu3050->hw_timestamp = iio_get_time_ns(indio_dev);
916 
917 	return IRQ_WAKE_THREAD;
918 }
919 
920 static irqreturn_t mpu3050_irq_thread(int irq, void *p)
921 {
922 	struct iio_trigger *trig = p;
923 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
924 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
925 	unsigned int val;
926 	int ret;
927 
928 	/* ACK IRQ and check if it was from us */
929 	ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
930 	if (ret) {
931 		dev_err(mpu3050->dev, "error reading IRQ status\n");
932 		return IRQ_HANDLED;
933 	}
934 	if (!(val & MPU3050_INT_STATUS_RAW_RDY))
935 		return IRQ_NONE;
936 
937 	iio_trigger_poll_nested(p);
938 
939 	return IRQ_HANDLED;
940 }
941 
942 /**
943  * mpu3050_drdy_trigger_set_state() - set data ready interrupt state
944  * @trig: trigger instance
945  * @enable: true if trigger should be enabled, false to disable
946  */
947 static int mpu3050_drdy_trigger_set_state(struct iio_trigger *trig,
948 					  bool enable)
949 {
950 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
951 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
952 	unsigned int val;
953 	int ret;
954 
955 	/* Disabling trigger: disable interrupt and return */
956 	if (!enable) {
957 		/* Disable all interrupts */
958 		ret = regmap_write(mpu3050->map,
959 				   MPU3050_INT_CFG,
960 				   0);
961 		if (ret)
962 			dev_err(mpu3050->dev, "error disabling IRQ\n");
963 
964 		/* Clear IRQ flag */
965 		ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
966 		if (ret)
967 			dev_err(mpu3050->dev, "error clearing IRQ status\n");
968 
969 		/* Disable all things in the FIFO and reset it */
970 		ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0);
971 		if (ret)
972 			dev_err(mpu3050->dev, "error disabling FIFO\n");
973 
974 		ret = regmap_write(mpu3050->map, MPU3050_USR_CTRL,
975 				   MPU3050_USR_CTRL_FIFO_RST);
976 		if (ret)
977 			dev_err(mpu3050->dev, "error resetting FIFO\n");
978 
979 		pm_runtime_mark_last_busy(mpu3050->dev);
980 		pm_runtime_put_autosuspend(mpu3050->dev);
981 		mpu3050->hw_irq_trigger = false;
982 
983 		return 0;
984 	} else {
985 		/* Else we're enabling the trigger from this point */
986 		pm_runtime_get_sync(mpu3050->dev);
987 		mpu3050->hw_irq_trigger = true;
988 
989 		/* Disable all things in the FIFO */
990 		ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN, 0);
991 		if (ret)
992 			return ret;
993 
994 		/* Reset and enable the FIFO */
995 		ret = regmap_set_bits(mpu3050->map, MPU3050_USR_CTRL,
996 				      MPU3050_USR_CTRL_FIFO_EN |
997 				      MPU3050_USR_CTRL_FIFO_RST);
998 		if (ret)
999 			return ret;
1000 
1001 		mpu3050->pending_fifo_footer = false;
1002 
1003 		/* Turn on the FIFO for temp+X+Y+Z */
1004 		ret = regmap_write(mpu3050->map, MPU3050_FIFO_EN,
1005 				   MPU3050_FIFO_EN_TEMP_OUT |
1006 				   MPU3050_FIFO_EN_GYRO_XOUT |
1007 				   MPU3050_FIFO_EN_GYRO_YOUT |
1008 				   MPU3050_FIFO_EN_GYRO_ZOUT |
1009 				   MPU3050_FIFO_EN_FOOTER);
1010 		if (ret)
1011 			return ret;
1012 
1013 		/* Configure the sample engine */
1014 		ret = mpu3050_start_sampling(mpu3050);
1015 		if (ret)
1016 			return ret;
1017 
1018 		/* Clear IRQ flag */
1019 		ret = regmap_read(mpu3050->map, MPU3050_INT_STATUS, &val);
1020 		if (ret)
1021 			dev_err(mpu3050->dev, "error clearing IRQ status\n");
1022 
1023 		/* Give us interrupts whenever there is new data ready */
1024 		val = MPU3050_INT_RAW_RDY_EN;
1025 
1026 		if (mpu3050->irq_actl)
1027 			val |= MPU3050_INT_ACTL;
1028 		if (mpu3050->irq_latch)
1029 			val |= MPU3050_INT_LATCH_EN;
1030 		if (mpu3050->irq_opendrain)
1031 			val |= MPU3050_INT_OPEN;
1032 
1033 		ret = regmap_write(mpu3050->map, MPU3050_INT_CFG, val);
1034 		if (ret)
1035 			return ret;
1036 	}
1037 
1038 	return 0;
1039 }
1040 
1041 static const struct iio_trigger_ops mpu3050_trigger_ops = {
1042 	.set_trigger_state = mpu3050_drdy_trigger_set_state,
1043 };
1044 
1045 static int mpu3050_trigger_probe(struct iio_dev *indio_dev, int irq)
1046 {
1047 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
1048 	struct device *dev = mpu3050->dev;
1049 	unsigned long irq_trig;
1050 	int ret;
1051 
1052 	mpu3050->trig = devm_iio_trigger_alloc(&indio_dev->dev,
1053 					       "%s-dev%d",
1054 					       indio_dev->name,
1055 					       iio_device_id(indio_dev));
1056 	if (!mpu3050->trig)
1057 		return -ENOMEM;
1058 
1059 	/* Check if IRQ is open drain */
1060 	mpu3050->irq_opendrain = device_property_read_bool(dev, "drive-open-drain");
1061 
1062 	/*
1063 	 * Configure the interrupt generator hardware to supply whatever
1064 	 * the interrupt is configured for, edges low/high level low/high,
1065 	 * we can provide it all.
1066 	 */
1067 	irq_trig = irq_get_trigger_type(irq);
1068 	switch (irq_trig) {
1069 	case IRQF_TRIGGER_RISING:
1070 		dev_info(&indio_dev->dev,
1071 			 "pulse interrupts on the rising edge\n");
1072 		break;
1073 	case IRQF_TRIGGER_FALLING:
1074 		mpu3050->irq_actl = true;
1075 		dev_info(&indio_dev->dev,
1076 			 "pulse interrupts on the falling edge\n");
1077 		break;
1078 	case IRQF_TRIGGER_HIGH:
1079 		mpu3050->irq_latch = true;
1080 		dev_info(&indio_dev->dev,
1081 			 "interrupts active high level\n");
1082 		/*
1083 		 * With level IRQs, we mask the IRQ until it is processed,
1084 		 * but with edge IRQs (pulses) we can queue several interrupts
1085 		 * in the top half.
1086 		 */
1087 		irq_trig |= IRQF_ONESHOT;
1088 		break;
1089 	case IRQF_TRIGGER_LOW:
1090 		mpu3050->irq_latch = true;
1091 		mpu3050->irq_actl = true;
1092 		irq_trig |= IRQF_ONESHOT;
1093 		dev_info(&indio_dev->dev,
1094 			 "interrupts active low level\n");
1095 		break;
1096 	default:
1097 		/* This is the most preferred mode, if possible */
1098 		dev_err(&indio_dev->dev,
1099 			"unsupported IRQ trigger specified (%lx), enforce "
1100 			"rising edge\n", irq_trig);
1101 		irq_trig = IRQF_TRIGGER_RISING;
1102 		break;
1103 	}
1104 
1105 	/* An open drain line can be shared with several devices */
1106 	if (mpu3050->irq_opendrain)
1107 		irq_trig |= IRQF_SHARED;
1108 
1109 	ret = request_threaded_irq(irq,
1110 				   mpu3050_irq_handler,
1111 				   mpu3050_irq_thread,
1112 				   irq_trig,
1113 				   mpu3050->trig->name,
1114 				   mpu3050->trig);
1115 	if (ret) {
1116 		dev_err(dev, "can't get IRQ %d, error %d\n", irq, ret);
1117 		return ret;
1118 	}
1119 
1120 	mpu3050->irq = irq;
1121 	mpu3050->trig->dev.parent = dev;
1122 	mpu3050->trig->ops = &mpu3050_trigger_ops;
1123 	iio_trigger_set_drvdata(mpu3050->trig, indio_dev);
1124 
1125 	ret = iio_trigger_register(mpu3050->trig);
1126 	if (ret)
1127 		return ret;
1128 
1129 	indio_dev->trig = iio_trigger_get(mpu3050->trig);
1130 
1131 	return 0;
1132 }
1133 
1134 int mpu3050_common_probe(struct device *dev,
1135 			 struct regmap *map,
1136 			 int irq,
1137 			 const char *name)
1138 {
1139 	struct iio_dev *indio_dev;
1140 	struct mpu3050 *mpu3050;
1141 	unsigned int val;
1142 	int ret;
1143 
1144 	indio_dev = devm_iio_device_alloc(dev, sizeof(*mpu3050));
1145 	if (!indio_dev)
1146 		return -ENOMEM;
1147 	mpu3050 = iio_priv(indio_dev);
1148 
1149 	mpu3050->dev = dev;
1150 	mpu3050->map = map;
1151 	mutex_init(&mpu3050->lock);
1152 	/* Default fullscale: 2000 degrees per second */
1153 	mpu3050->fullscale = FS_2000_DPS;
1154 	/* 1 kHz, divide by 100, default frequency = 10 Hz */
1155 	mpu3050->lpf = MPU3050_DLPF_CFG_188HZ;
1156 	mpu3050->divisor = 99;
1157 
1158 	/* Read the mounting matrix, if present */
1159 	ret = iio_read_mount_matrix(dev, &mpu3050->orientation);
1160 	if (ret)
1161 		return ret;
1162 
1163 	/* Fetch and turn on regulators */
1164 	mpu3050->regs[0].supply = mpu3050_reg_vdd;
1165 	mpu3050->regs[1].supply = mpu3050_reg_vlogic;
1166 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(mpu3050->regs),
1167 				      mpu3050->regs);
1168 	if (ret) {
1169 		dev_err(dev, "Cannot get regulators\n");
1170 		return ret;
1171 	}
1172 
1173 	ret = mpu3050_power_up(mpu3050);
1174 	if (ret)
1175 		return ret;
1176 
1177 	ret = regmap_read(map, MPU3050_CHIP_ID_REG, &val);
1178 	if (ret) {
1179 		dev_err(dev, "could not read device ID\n");
1180 		ret = -ENODEV;
1181 
1182 		goto err_power_down;
1183 	}
1184 
1185 	if ((val & MPU3050_CHIP_ID_MASK) != MPU3050_CHIP_ID) {
1186 		dev_err(dev, "unsupported chip id %02x\n",
1187 				(u8)(val & MPU3050_CHIP_ID_MASK));
1188 		ret = -ENODEV;
1189 		goto err_power_down;
1190 	}
1191 
1192 	ret = regmap_read(map, MPU3050_PRODUCT_ID_REG, &val);
1193 	if (ret) {
1194 		dev_err(dev, "could not read device ID\n");
1195 		ret = -ENODEV;
1196 
1197 		goto err_power_down;
1198 	}
1199 	dev_info(dev, "found MPU-3050 part no: %d, version: %d\n",
1200 		 ((val >> 4) & 0xf), (val & 0xf));
1201 
1202 	ret = mpu3050_hw_init(mpu3050);
1203 	if (ret)
1204 		goto err_power_down;
1205 
1206 	indio_dev->channels = mpu3050_channels;
1207 	indio_dev->num_channels = ARRAY_SIZE(mpu3050_channels);
1208 	indio_dev->info = &mpu3050_info;
1209 	indio_dev->available_scan_masks = mpu3050_scan_masks;
1210 	indio_dev->modes = INDIO_DIRECT_MODE;
1211 	indio_dev->name = name;
1212 
1213 	ret = iio_triggered_buffer_setup(indio_dev, iio_pollfunc_store_time,
1214 					 mpu3050_trigger_handler,
1215 					 &mpu3050_buffer_setup_ops);
1216 	if (ret) {
1217 		dev_err(dev, "triggered buffer setup failed\n");
1218 		goto err_power_down;
1219 	}
1220 
1221 	ret = iio_device_register(indio_dev);
1222 	if (ret) {
1223 		dev_err(dev, "device register failed\n");
1224 		goto err_cleanup_buffer;
1225 	}
1226 
1227 	dev_set_drvdata(dev, indio_dev);
1228 
1229 	/* Check if we have an assigned IRQ to use as trigger */
1230 	if (irq) {
1231 		ret = mpu3050_trigger_probe(indio_dev, irq);
1232 		if (ret)
1233 			dev_err(dev, "failed to register trigger\n");
1234 	}
1235 
1236 	/* Enable runtime PM */
1237 	pm_runtime_get_noresume(dev);
1238 	pm_runtime_set_active(dev);
1239 	pm_runtime_enable(dev);
1240 	/*
1241 	 * Set autosuspend to two orders of magnitude larger than the
1242 	 * start-up time. 100ms start-up time means 10000ms autosuspend,
1243 	 * i.e. 10 seconds.
1244 	 */
1245 	pm_runtime_set_autosuspend_delay(dev, 10000);
1246 	pm_runtime_use_autosuspend(dev);
1247 	pm_runtime_put(dev);
1248 
1249 	return 0;
1250 
1251 err_cleanup_buffer:
1252 	iio_triggered_buffer_cleanup(indio_dev);
1253 err_power_down:
1254 	mpu3050_power_down(mpu3050);
1255 
1256 	return ret;
1257 }
1258 
1259 void mpu3050_common_remove(struct device *dev)
1260 {
1261 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1262 	struct mpu3050 *mpu3050 = iio_priv(indio_dev);
1263 
1264 	pm_runtime_get_sync(dev);
1265 	pm_runtime_put_noidle(dev);
1266 	pm_runtime_disable(dev);
1267 	iio_triggered_buffer_cleanup(indio_dev);
1268 	if (mpu3050->irq)
1269 		free_irq(mpu3050->irq, mpu3050);
1270 	iio_device_unregister(indio_dev);
1271 	mpu3050_power_down(mpu3050);
1272 }
1273 
1274 static int mpu3050_runtime_suspend(struct device *dev)
1275 {
1276 	return mpu3050_power_down(iio_priv(dev_get_drvdata(dev)));
1277 }
1278 
1279 static int mpu3050_runtime_resume(struct device *dev)
1280 {
1281 	return mpu3050_power_up(iio_priv(dev_get_drvdata(dev)));
1282 }
1283 
1284 DEFINE_RUNTIME_DEV_PM_OPS(mpu3050_dev_pm_ops, mpu3050_runtime_suspend,
1285 			  mpu3050_runtime_resume, NULL);
1286 MODULE_AUTHOR("Linus Walleij");
1287 MODULE_DESCRIPTION("MPU3050 gyroscope driver");
1288 MODULE_LICENSE("GPL");
1289