xref: /linux/drivers/iio/magnetometer/bmc150_magn.c (revision 68a052239fc4b351e961f698b824f7654a346091)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Bosch BMC150 three-axis magnetic field sensor driver
4  *
5  * Copyright (c) 2015, Intel Corporation.
6  *
7  * This code is based on bmm050_api.c authored by contact@bosch.sensortec.com:
8  *
9  * (C) Copyright 2011~2014 Bosch Sensortec GmbH All Rights Reserved
10  */
11 
12 #include <linux/module.h>
13 #include <linux/i2c.h>
14 #include <linux/interrupt.h>
15 #include <linux/delay.h>
16 #include <linux/slab.h>
17 #include <linux/pm.h>
18 #include <linux/pm_runtime.h>
19 #include <linux/iio/iio.h>
20 #include <linux/iio/sysfs.h>
21 #include <linux/iio/buffer.h>
22 #include <linux/iio/events.h>
23 #include <linux/iio/trigger.h>
24 #include <linux/iio/trigger_consumer.h>
25 #include <linux/iio/triggered_buffer.h>
26 #include <linux/regmap.h>
27 #include <linux/regulator/consumer.h>
28 
29 #include "bmc150_magn.h"
30 
31 #define BMC150_MAGN_REG_CHIP_ID			0x40
32 #define BMC150_MAGN_CHIP_ID_VAL			0x32
33 
34 #define BMC150_MAGN_REG_X_L			0x42
35 #define BMC150_MAGN_REG_X_M			0x43
36 #define BMC150_MAGN_REG_Y_L			0x44
37 #define BMC150_MAGN_REG_Y_M			0x45
38 #define BMC150_MAGN_SHIFT_XY_L			3
39 #define BMC150_MAGN_REG_Z_L			0x46
40 #define BMC150_MAGN_REG_Z_M			0x47
41 #define BMC150_MAGN_SHIFT_Z_L			1
42 #define BMC150_MAGN_REG_RHALL_L			0x48
43 #define BMC150_MAGN_REG_RHALL_M			0x49
44 #define BMC150_MAGN_SHIFT_RHALL_L		2
45 
46 #define BMC150_MAGN_REG_INT_STATUS		0x4A
47 
48 #define BMC150_MAGN_REG_POWER			0x4B
49 #define BMC150_MAGN_MASK_POWER_CTL		BIT(0)
50 
51 #define BMC150_MAGN_REG_OPMODE_ODR		0x4C
52 #define BMC150_MAGN_MASK_OPMODE			GENMASK(2, 1)
53 #define BMC150_MAGN_SHIFT_OPMODE		1
54 #define BMC150_MAGN_MODE_NORMAL			0x00
55 #define BMC150_MAGN_MODE_FORCED			0x01
56 #define BMC150_MAGN_MODE_SLEEP			0x03
57 #define BMC150_MAGN_MASK_ODR			GENMASK(5, 3)
58 #define BMC150_MAGN_SHIFT_ODR			3
59 
60 #define BMC150_MAGN_REG_INT			0x4D
61 
62 #define BMC150_MAGN_REG_INT_DRDY		0x4E
63 #define BMC150_MAGN_MASK_DRDY_EN		BIT(7)
64 #define BMC150_MAGN_SHIFT_DRDY_EN		7
65 #define BMC150_MAGN_MASK_DRDY_INT3		BIT(6)
66 #define BMC150_MAGN_MASK_DRDY_Z_EN		BIT(5)
67 #define BMC150_MAGN_MASK_DRDY_Y_EN		BIT(4)
68 #define BMC150_MAGN_MASK_DRDY_X_EN		BIT(3)
69 #define BMC150_MAGN_MASK_DRDY_DR_POLARITY	BIT(2)
70 #define BMC150_MAGN_MASK_DRDY_LATCHING		BIT(1)
71 #define BMC150_MAGN_MASK_DRDY_INT3_POLARITY	BIT(0)
72 
73 #define BMC150_MAGN_REG_LOW_THRESH		0x4F
74 #define BMC150_MAGN_REG_HIGH_THRESH		0x50
75 #define BMC150_MAGN_REG_REP_XY			0x51
76 #define BMC150_MAGN_REG_REP_Z			0x52
77 #define BMC150_MAGN_REG_REP_DATAMASK		GENMASK(7, 0)
78 
79 #define BMC150_MAGN_REG_TRIM_START		0x5D
80 #define BMC150_MAGN_REG_TRIM_END		0x71
81 
82 #define BMC150_MAGN_XY_OVERFLOW_VAL		-4096
83 #define BMC150_MAGN_Z_OVERFLOW_VAL		-16384
84 
85 /* Time from SUSPEND to SLEEP */
86 #define BMC150_MAGN_START_UP_TIME_MS		3
87 
88 #define BMC150_MAGN_AUTO_SUSPEND_DELAY_MS	2000
89 
90 #define BMC150_MAGN_REGVAL_TO_REPXY(regval) (((regval) * 2) + 1)
91 #define BMC150_MAGN_REGVAL_TO_REPZ(regval) ((regval) + 1)
92 #define BMC150_MAGN_REPXY_TO_REGVAL(rep) (((rep) - 1) / 2)
93 #define BMC150_MAGN_REPZ_TO_REGVAL(rep) ((rep) - 1)
94 
95 enum bmc150_magn_axis {
96 	AXIS_X,
97 	AXIS_Y,
98 	AXIS_Z,
99 	RHALL,
100 	AXIS_XYZ_MAX = RHALL,
101 	AXIS_XYZR_MAX,
102 };
103 
104 enum bmc150_magn_power_modes {
105 	BMC150_MAGN_POWER_MODE_SUSPEND,
106 	BMC150_MAGN_POWER_MODE_SLEEP,
107 	BMC150_MAGN_POWER_MODE_NORMAL,
108 };
109 
110 struct bmc150_magn_trim_regs {
111 	s8 x1;
112 	s8 y1;
113 	__le16 reserved1;
114 	u8 reserved2;
115 	__le16 z4;
116 	s8 x2;
117 	s8 y2;
118 	__le16 reserved3;
119 	__le16 z2;
120 	__le16 z1;
121 	__le16 xyz1;
122 	__le16 z3;
123 	s8 xy2;
124 	u8 xy1;
125 } __packed;
126 
127 struct bmc150_magn_data {
128 	struct device *dev;
129 	/*
130 	 * 1. Protect this structure.
131 	 * 2. Serialize sequences that power on/off the device and access HW.
132 	 */
133 	struct mutex mutex;
134 	struct regmap *regmap;
135 	struct regulator_bulk_data regulators[2];
136 	struct iio_mount_matrix orientation;
137 	/* Ensure timestamp is naturally aligned */
138 	struct {
139 		s32 chans[3];
140 		aligned_s64 timestamp;
141 	} scan;
142 	struct iio_trigger *dready_trig;
143 	bool dready_trigger_on;
144 	int max_odr;
145 	int irq;
146 };
147 
148 static const struct {
149 	int freq;
150 	u8 reg_val;
151 } bmc150_magn_samp_freq_table[] = { {2, 0x01},
152 				    {6, 0x02},
153 				    {8, 0x03},
154 				    {10, 0x00},
155 				    {15, 0x04},
156 				    {20, 0x05},
157 				    {25, 0x06},
158 				    {30, 0x07} };
159 
160 enum bmc150_magn_presets {
161 	LOW_POWER_PRESET,
162 	REGULAR_PRESET,
163 	ENHANCED_REGULAR_PRESET,
164 	HIGH_ACCURACY_PRESET
165 };
166 
167 static const struct bmc150_magn_preset {
168 	u8 rep_xy;
169 	u8 rep_z;
170 	u8 odr;
171 } bmc150_magn_presets_table[] = {
172 	[LOW_POWER_PRESET] = {3, 3, 10},
173 	[REGULAR_PRESET] =  {9, 15, 10},
174 	[ENHANCED_REGULAR_PRESET] =  {15, 27, 10},
175 	[HIGH_ACCURACY_PRESET] =  {47, 83, 20},
176 };
177 
178 #define BMC150_MAGN_DEFAULT_PRESET REGULAR_PRESET
179 
180 static bool bmc150_magn_is_writeable_reg(struct device *dev, unsigned int reg)
181 {
182 	switch (reg) {
183 	case BMC150_MAGN_REG_POWER:
184 	case BMC150_MAGN_REG_OPMODE_ODR:
185 	case BMC150_MAGN_REG_INT:
186 	case BMC150_MAGN_REG_INT_DRDY:
187 	case BMC150_MAGN_REG_LOW_THRESH:
188 	case BMC150_MAGN_REG_HIGH_THRESH:
189 	case BMC150_MAGN_REG_REP_XY:
190 	case BMC150_MAGN_REG_REP_Z:
191 		return true;
192 	default:
193 		return false;
194 	}
195 }
196 
197 static bool bmc150_magn_is_volatile_reg(struct device *dev, unsigned int reg)
198 {
199 	switch (reg) {
200 	case BMC150_MAGN_REG_X_L:
201 	case BMC150_MAGN_REG_X_M:
202 	case BMC150_MAGN_REG_Y_L:
203 	case BMC150_MAGN_REG_Y_M:
204 	case BMC150_MAGN_REG_Z_L:
205 	case BMC150_MAGN_REG_Z_M:
206 	case BMC150_MAGN_REG_RHALL_L:
207 	case BMC150_MAGN_REG_RHALL_M:
208 	case BMC150_MAGN_REG_INT_STATUS:
209 		return true;
210 	default:
211 		return false;
212 	}
213 }
214 
215 const struct regmap_config bmc150_magn_regmap_config = {
216 	.reg_bits = 8,
217 	.val_bits = 8,
218 
219 	.max_register = BMC150_MAGN_REG_TRIM_END,
220 	.cache_type = REGCACHE_RBTREE,
221 
222 	.writeable_reg = bmc150_magn_is_writeable_reg,
223 	.volatile_reg = bmc150_magn_is_volatile_reg,
224 };
225 EXPORT_SYMBOL_NS(bmc150_magn_regmap_config, "IIO_BMC150_MAGN");
226 
227 static int bmc150_magn_set_power_mode(struct bmc150_magn_data *data,
228 				      enum bmc150_magn_power_modes mode,
229 				      bool state)
230 {
231 	int ret;
232 
233 	switch (mode) {
234 	case BMC150_MAGN_POWER_MODE_SUSPEND:
235 		ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_POWER,
236 					 BMC150_MAGN_MASK_POWER_CTL, !state);
237 		if (ret < 0)
238 			return ret;
239 		usleep_range(BMC150_MAGN_START_UP_TIME_MS * 1000, 20000);
240 		return 0;
241 	case BMC150_MAGN_POWER_MODE_SLEEP:
242 		return regmap_update_bits(data->regmap,
243 					  BMC150_MAGN_REG_OPMODE_ODR,
244 					  BMC150_MAGN_MASK_OPMODE,
245 					  BMC150_MAGN_MODE_SLEEP <<
246 					  BMC150_MAGN_SHIFT_OPMODE);
247 	case BMC150_MAGN_POWER_MODE_NORMAL:
248 		return regmap_update_bits(data->regmap,
249 					  BMC150_MAGN_REG_OPMODE_ODR,
250 					  BMC150_MAGN_MASK_OPMODE,
251 					  BMC150_MAGN_MODE_NORMAL <<
252 					  BMC150_MAGN_SHIFT_OPMODE);
253 	}
254 
255 	return -EINVAL;
256 }
257 
258 static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
259 {
260 	int ret = 0;
261 
262 	if (on)
263 		ret = pm_runtime_resume_and_get(data->dev);
264 	else
265 		pm_runtime_put_autosuspend(data->dev);
266 	if (ret < 0) {
267 		dev_err(data->dev,
268 			"failed to change power state to %d\n", on);
269 		return ret;
270 	}
271 
272 	return 0;
273 }
274 
275 static int bmc150_magn_get_odr(struct bmc150_magn_data *data, int *val)
276 {
277 	int ret, reg_val;
278 	u8 i, odr_val;
279 
280 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_OPMODE_ODR, &reg_val);
281 	if (ret < 0)
282 		return ret;
283 	odr_val = (reg_val & BMC150_MAGN_MASK_ODR) >> BMC150_MAGN_SHIFT_ODR;
284 
285 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++)
286 		if (bmc150_magn_samp_freq_table[i].reg_val == odr_val) {
287 			*val = bmc150_magn_samp_freq_table[i].freq;
288 			return 0;
289 		}
290 
291 	return -EINVAL;
292 }
293 
294 static int bmc150_magn_set_odr(struct bmc150_magn_data *data, int val)
295 {
296 	int ret;
297 	u8 i;
298 
299 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
300 		if (bmc150_magn_samp_freq_table[i].freq == val) {
301 			ret = regmap_update_bits(data->regmap,
302 						 BMC150_MAGN_REG_OPMODE_ODR,
303 						 BMC150_MAGN_MASK_ODR,
304 						 bmc150_magn_samp_freq_table[i].
305 						 reg_val <<
306 						 BMC150_MAGN_SHIFT_ODR);
307 			if (ret < 0)
308 				return ret;
309 			return 0;
310 		}
311 	}
312 
313 	return -EINVAL;
314 }
315 
316 static int bmc150_magn_set_max_odr(struct bmc150_magn_data *data, int rep_xy,
317 				   int rep_z, int odr)
318 {
319 	int ret, reg_val, max_odr;
320 
321 	if (rep_xy <= 0) {
322 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
323 				  &reg_val);
324 		if (ret < 0)
325 			return ret;
326 		rep_xy = BMC150_MAGN_REGVAL_TO_REPXY(reg_val);
327 	}
328 	if (rep_z <= 0) {
329 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
330 				  &reg_val);
331 		if (ret < 0)
332 			return ret;
333 		rep_z = BMC150_MAGN_REGVAL_TO_REPZ(reg_val);
334 	}
335 	if (odr <= 0) {
336 		ret = bmc150_magn_get_odr(data, &odr);
337 		if (ret < 0)
338 			return ret;
339 	}
340 	/* the maximum selectable read-out frequency from datasheet */
341 	max_odr = 1000000 / (145 * rep_xy + 500 * rep_z + 980);
342 	if (odr > max_odr) {
343 		dev_err(data->dev,
344 			"Can't set oversampling with sampling freq %d\n",
345 			odr);
346 		return -EINVAL;
347 	}
348 	data->max_odr = max_odr;
349 
350 	return 0;
351 }
352 
353 static s32 bmc150_magn_compensate_x(struct bmc150_magn_trim_regs *tregs, s16 x,
354 				    u16 rhall)
355 {
356 	s16 val;
357 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
358 
359 	if (x == BMC150_MAGN_XY_OVERFLOW_VAL)
360 		return S32_MIN;
361 
362 	if (!rhall)
363 		rhall = xyz1;
364 
365 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
366 	val = ((s16)((((s32)x) * ((((((((s32)tregs->xy2) * ((((s32)val) *
367 	      ((s32)val)) >> 7)) + (((s32)val) *
368 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
369 	      ((s32)(((s16)tregs->x2) + ((s16)0xA0)))) >> 12)) >> 13)) +
370 	      (((s16)tregs->x1) << 3);
371 
372 	return (s32)val;
373 }
374 
375 static s32 bmc150_magn_compensate_y(struct bmc150_magn_trim_regs *tregs, s16 y,
376 				    u16 rhall)
377 {
378 	s16 val;
379 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
380 
381 	if (y == BMC150_MAGN_XY_OVERFLOW_VAL)
382 		return S32_MIN;
383 
384 	if (!rhall)
385 		rhall = xyz1;
386 
387 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
388 	val = ((s16)((((s32)y) * ((((((((s32)tregs->xy2) * ((((s32)val) *
389 	      ((s32)val)) >> 7)) + (((s32)val) *
390 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
391 	      ((s32)(((s16)tregs->y2) + ((s16)0xA0)))) >> 12)) >> 13)) +
392 	      (((s16)tregs->y1) << 3);
393 
394 	return (s32)val;
395 }
396 
397 static s32 bmc150_magn_compensate_z(struct bmc150_magn_trim_regs *tregs, s16 z,
398 				    u16 rhall)
399 {
400 	s32 val;
401 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
402 	u16 z1 = le16_to_cpu(tregs->z1);
403 	s16 z2 = le16_to_cpu(tregs->z2);
404 	s16 z3 = le16_to_cpu(tregs->z3);
405 	s16 z4 = le16_to_cpu(tregs->z4);
406 
407 	if (z == BMC150_MAGN_Z_OVERFLOW_VAL)
408 		return S32_MIN;
409 
410 	val = (((((s32)(z - z4)) << 15) - ((((s32)z3) * ((s32)(((s16)rhall) -
411 	      ((s16)xyz1)))) >> 2)) / (z2 + ((s16)(((((s32)z1) *
412 	      ((((s16)rhall) << 1))) + (1 << 15)) >> 16))));
413 
414 	return val;
415 }
416 
417 static int bmc150_magn_read_xyz(struct bmc150_magn_data *data, s32 *buffer)
418 {
419 	int ret;
420 	__le16 values[AXIS_XYZR_MAX];
421 	s16 raw_x, raw_y, raw_z;
422 	u16 rhall;
423 	struct bmc150_magn_trim_regs tregs;
424 
425 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_X_L,
426 			       values, sizeof(values));
427 	if (ret < 0)
428 		return ret;
429 
430 	raw_x = (s16)le16_to_cpu(values[AXIS_X]) >> BMC150_MAGN_SHIFT_XY_L;
431 	raw_y = (s16)le16_to_cpu(values[AXIS_Y]) >> BMC150_MAGN_SHIFT_XY_L;
432 	raw_z = (s16)le16_to_cpu(values[AXIS_Z]) >> BMC150_MAGN_SHIFT_Z_L;
433 	rhall = le16_to_cpu(values[RHALL]) >> BMC150_MAGN_SHIFT_RHALL_L;
434 
435 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_TRIM_START,
436 			       &tregs, sizeof(tregs));
437 	if (ret < 0)
438 		return ret;
439 
440 	buffer[AXIS_X] = bmc150_magn_compensate_x(&tregs, raw_x, rhall);
441 	buffer[AXIS_Y] = bmc150_magn_compensate_y(&tregs, raw_y, rhall);
442 	buffer[AXIS_Z] = bmc150_magn_compensate_z(&tregs, raw_z, rhall);
443 
444 	return 0;
445 }
446 
447 static int bmc150_magn_read_raw(struct iio_dev *indio_dev,
448 				struct iio_chan_spec const *chan,
449 				int *val, int *val2, long mask)
450 {
451 	struct bmc150_magn_data *data = iio_priv(indio_dev);
452 	int ret, tmp;
453 	s32 values[AXIS_XYZ_MAX];
454 
455 	switch (mask) {
456 	case IIO_CHAN_INFO_RAW:
457 		if (iio_buffer_enabled(indio_dev))
458 			return -EBUSY;
459 		mutex_lock(&data->mutex);
460 
461 		ret = bmc150_magn_set_power_state(data, true);
462 		if (ret < 0) {
463 			mutex_unlock(&data->mutex);
464 			return ret;
465 		}
466 
467 		ret = bmc150_magn_read_xyz(data, values);
468 		if (ret < 0) {
469 			bmc150_magn_set_power_state(data, false);
470 			mutex_unlock(&data->mutex);
471 			return ret;
472 		}
473 		*val = values[chan->scan_index];
474 
475 		ret = bmc150_magn_set_power_state(data, false);
476 		if (ret < 0) {
477 			mutex_unlock(&data->mutex);
478 			return ret;
479 		}
480 
481 		mutex_unlock(&data->mutex);
482 		return IIO_VAL_INT;
483 	case IIO_CHAN_INFO_SCALE:
484 		/*
485 		 * The API/driver performs an off-chip temperature
486 		 * compensation and outputs x/y/z magnetic field data in
487 		 * 16 LSB/uT to the upper application layer.
488 		 */
489 		*val = 0;
490 		*val2 = 625;
491 		return IIO_VAL_INT_PLUS_MICRO;
492 	case IIO_CHAN_INFO_SAMP_FREQ:
493 		ret = bmc150_magn_get_odr(data, val);
494 		if (ret < 0)
495 			return ret;
496 		return IIO_VAL_INT;
497 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
498 		switch (chan->channel2) {
499 		case IIO_MOD_X:
500 		case IIO_MOD_Y:
501 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
502 					  &tmp);
503 			if (ret < 0)
504 				return ret;
505 			*val = BMC150_MAGN_REGVAL_TO_REPXY(tmp);
506 			return IIO_VAL_INT;
507 		case IIO_MOD_Z:
508 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
509 					  &tmp);
510 			if (ret < 0)
511 				return ret;
512 			*val = BMC150_MAGN_REGVAL_TO_REPZ(tmp);
513 			return IIO_VAL_INT;
514 		default:
515 			return -EINVAL;
516 		}
517 	default:
518 		return -EINVAL;
519 	}
520 }
521 
522 static int bmc150_magn_write_raw(struct iio_dev *indio_dev,
523 				 struct iio_chan_spec const *chan,
524 				 int val, int val2, long mask)
525 {
526 	struct bmc150_magn_data *data = iio_priv(indio_dev);
527 	int ret;
528 
529 	switch (mask) {
530 	case IIO_CHAN_INFO_SAMP_FREQ:
531 		if (val > data->max_odr)
532 			return -EINVAL;
533 		mutex_lock(&data->mutex);
534 		ret = bmc150_magn_set_odr(data, val);
535 		mutex_unlock(&data->mutex);
536 		return ret;
537 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
538 		switch (chan->channel2) {
539 		case IIO_MOD_X:
540 		case IIO_MOD_Y:
541 			if (val < 1 || val > 511)
542 				return -EINVAL;
543 			mutex_lock(&data->mutex);
544 			ret = bmc150_magn_set_max_odr(data, val, 0, 0);
545 			if (ret < 0) {
546 				mutex_unlock(&data->mutex);
547 				return ret;
548 			}
549 			ret = regmap_update_bits(data->regmap,
550 						 BMC150_MAGN_REG_REP_XY,
551 						 BMC150_MAGN_REG_REP_DATAMASK,
552 						 BMC150_MAGN_REPXY_TO_REGVAL
553 						 (val));
554 			mutex_unlock(&data->mutex);
555 			return ret;
556 		case IIO_MOD_Z:
557 			if (val < 1 || val > 256)
558 				return -EINVAL;
559 			mutex_lock(&data->mutex);
560 			ret = bmc150_magn_set_max_odr(data, 0, val, 0);
561 			if (ret < 0) {
562 				mutex_unlock(&data->mutex);
563 				return ret;
564 			}
565 			ret = regmap_update_bits(data->regmap,
566 						 BMC150_MAGN_REG_REP_Z,
567 						 BMC150_MAGN_REG_REP_DATAMASK,
568 						 BMC150_MAGN_REPZ_TO_REGVAL
569 						 (val));
570 			mutex_unlock(&data->mutex);
571 			return ret;
572 		default:
573 			return -EINVAL;
574 		}
575 	default:
576 		return -EINVAL;
577 	}
578 }
579 
580 static ssize_t bmc150_magn_show_samp_freq_avail(struct device *dev,
581 						struct device_attribute *attr,
582 						char *buf)
583 {
584 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
585 	struct bmc150_magn_data *data = iio_priv(indio_dev);
586 	size_t len = 0;
587 	u8 i;
588 
589 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
590 		if (bmc150_magn_samp_freq_table[i].freq > data->max_odr)
591 			break;
592 		len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
593 				 bmc150_magn_samp_freq_table[i].freq);
594 	}
595 	/* replace last space with a newline */
596 	buf[len - 1] = '\n';
597 
598 	return len;
599 }
600 
601 static const struct iio_mount_matrix *
602 bmc150_magn_get_mount_matrix(const struct iio_dev *indio_dev,
603 			      const struct iio_chan_spec *chan)
604 {
605 	struct bmc150_magn_data *data = iio_priv(indio_dev);
606 
607 	return &data->orientation;
608 }
609 
610 static const struct iio_chan_spec_ext_info bmc150_magn_ext_info[] = {
611 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bmc150_magn_get_mount_matrix),
612 	{ }
613 };
614 
615 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(bmc150_magn_show_samp_freq_avail);
616 
617 static struct attribute *bmc150_magn_attributes[] = {
618 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
619 	NULL,
620 };
621 
622 static const struct attribute_group bmc150_magn_attrs_group = {
623 	.attrs = bmc150_magn_attributes,
624 };
625 
626 #define BMC150_MAGN_CHANNEL(_axis) {					\
627 	.type = IIO_MAGN,						\
628 	.modified = 1,							\
629 	.channel2 = IIO_MOD_##_axis,					\
630 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
631 			      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
632 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |	\
633 				    BIT(IIO_CHAN_INFO_SCALE),		\
634 	.scan_index = AXIS_##_axis,					\
635 	.scan_type = {							\
636 		.sign = 's',						\
637 		.realbits = 32,						\
638 		.storagebits = 32,					\
639 		.endianness = IIO_LE					\
640 	},								\
641 	.ext_info = bmc150_magn_ext_info,				\
642 }
643 
644 static const struct iio_chan_spec bmc150_magn_channels[] = {
645 	BMC150_MAGN_CHANNEL(X),
646 	BMC150_MAGN_CHANNEL(Y),
647 	BMC150_MAGN_CHANNEL(Z),
648 	IIO_CHAN_SOFT_TIMESTAMP(3),
649 };
650 
651 static const struct iio_info bmc150_magn_info = {
652 	.attrs = &bmc150_magn_attrs_group,
653 	.read_raw = bmc150_magn_read_raw,
654 	.write_raw = bmc150_magn_write_raw,
655 };
656 
657 static const unsigned long bmc150_magn_scan_masks[] = {
658 					BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
659 					0};
660 
661 static irqreturn_t bmc150_magn_trigger_handler(int irq, void *p)
662 {
663 	struct iio_poll_func *pf = p;
664 	struct iio_dev *indio_dev = pf->indio_dev;
665 	struct bmc150_magn_data *data = iio_priv(indio_dev);
666 	int ret;
667 
668 	mutex_lock(&data->mutex);
669 	ret = bmc150_magn_read_xyz(data, data->scan.chans);
670 	if (ret < 0)
671 		goto err;
672 
673 	iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
674 				    pf->timestamp);
675 
676 err:
677 	mutex_unlock(&data->mutex);
678 	iio_trigger_notify_done(indio_dev->trig);
679 
680 	return IRQ_HANDLED;
681 }
682 
683 static int bmc150_magn_init(struct bmc150_magn_data *data)
684 {
685 	int ret, chip_id;
686 	struct bmc150_magn_preset preset;
687 
688 	ret = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
689 				    data->regulators);
690 	if (ret < 0) {
691 		dev_err(data->dev, "Failed to enable regulators: %d\n", ret);
692 		return ret;
693 	}
694 	/*
695 	 * 3ms power-on time according to datasheet, let's better
696 	 * be safe than sorry and set this delay to 5ms.
697 	 */
698 	msleep(5);
699 
700 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND,
701 					 false);
702 	if (ret < 0) {
703 		dev_err(data->dev,
704 			"Failed to bring up device from suspend mode\n");
705 		goto err_regulator_disable;
706 	}
707 
708 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_CHIP_ID, &chip_id);
709 	if (ret < 0) {
710 		dev_err(data->dev, "Failed reading chip id\n");
711 		goto err_poweroff;
712 	}
713 	if (chip_id != BMC150_MAGN_CHIP_ID_VAL) {
714 		dev_err(data->dev, "Invalid chip id 0x%x\n", chip_id);
715 		ret = -ENODEV;
716 		goto err_poweroff;
717 	}
718 	dev_dbg(data->dev, "Chip id %x\n", chip_id);
719 
720 	preset = bmc150_magn_presets_table[BMC150_MAGN_DEFAULT_PRESET];
721 	ret = bmc150_magn_set_odr(data, preset.odr);
722 	if (ret < 0) {
723 		dev_err(data->dev, "Failed to set ODR to %d\n",
724 			preset.odr);
725 		goto err_poweroff;
726 	}
727 
728 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_XY,
729 			   BMC150_MAGN_REPXY_TO_REGVAL(preset.rep_xy));
730 	if (ret < 0) {
731 		dev_err(data->dev, "Failed to set REP XY to %d\n",
732 			preset.rep_xy);
733 		goto err_poweroff;
734 	}
735 
736 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_Z,
737 			   BMC150_MAGN_REPZ_TO_REGVAL(preset.rep_z));
738 	if (ret < 0) {
739 		dev_err(data->dev, "Failed to set REP Z to %d\n",
740 			preset.rep_z);
741 		goto err_poweroff;
742 	}
743 
744 	ret = bmc150_magn_set_max_odr(data, preset.rep_xy, preset.rep_z,
745 				      preset.odr);
746 	if (ret < 0)
747 		goto err_poweroff;
748 
749 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
750 					 true);
751 	if (ret < 0) {
752 		dev_err(data->dev, "Failed to power on device\n");
753 		goto err_poweroff;
754 	}
755 
756 	return 0;
757 
758 err_poweroff:
759 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
760 err_regulator_disable:
761 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
762 	return ret;
763 }
764 
765 static int bmc150_magn_reset_intr(struct bmc150_magn_data *data)
766 {
767 	int tmp;
768 
769 	/*
770 	 * Data Ready (DRDY) is always cleared after
771 	 * readout of data registers ends.
772 	 */
773 	return regmap_read(data->regmap, BMC150_MAGN_REG_X_L, &tmp);
774 }
775 
776 static void bmc150_magn_trig_reen(struct iio_trigger *trig)
777 {
778 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
779 	struct bmc150_magn_data *data = iio_priv(indio_dev);
780 	int ret;
781 
782 	if (!data->dready_trigger_on)
783 		return;
784 
785 	mutex_lock(&data->mutex);
786 	ret = bmc150_magn_reset_intr(data);
787 	mutex_unlock(&data->mutex);
788 	if (ret)
789 		dev_err(data->dev, "Failed to reset interrupt\n");
790 }
791 
792 static int bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger *trig,
793 						  bool state)
794 {
795 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
796 	struct bmc150_magn_data *data = iio_priv(indio_dev);
797 	int ret = 0;
798 
799 	mutex_lock(&data->mutex);
800 	if (state == data->dready_trigger_on)
801 		goto err_unlock;
802 
803 	ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_INT_DRDY,
804 				 BMC150_MAGN_MASK_DRDY_EN,
805 				 state << BMC150_MAGN_SHIFT_DRDY_EN);
806 	if (ret < 0)
807 		goto err_unlock;
808 
809 	data->dready_trigger_on = state;
810 
811 	if (state) {
812 		ret = bmc150_magn_reset_intr(data);
813 		if (ret < 0)
814 			goto err_unlock;
815 	}
816 	mutex_unlock(&data->mutex);
817 
818 	return 0;
819 
820 err_unlock:
821 	mutex_unlock(&data->mutex);
822 	return ret;
823 }
824 
825 static const struct iio_trigger_ops bmc150_magn_trigger_ops = {
826 	.set_trigger_state = bmc150_magn_data_rdy_trigger_set_state,
827 	.reenable = bmc150_magn_trig_reen,
828 };
829 
830 static int bmc150_magn_buffer_preenable(struct iio_dev *indio_dev)
831 {
832 	struct bmc150_magn_data *data = iio_priv(indio_dev);
833 
834 	return bmc150_magn_set_power_state(data, true);
835 }
836 
837 static int bmc150_magn_buffer_postdisable(struct iio_dev *indio_dev)
838 {
839 	struct bmc150_magn_data *data = iio_priv(indio_dev);
840 
841 	return bmc150_magn_set_power_state(data, false);
842 }
843 
844 static const struct iio_buffer_setup_ops bmc150_magn_buffer_setup_ops = {
845 	.preenable = bmc150_magn_buffer_preenable,
846 	.postdisable = bmc150_magn_buffer_postdisable,
847 };
848 
849 int bmc150_magn_probe(struct device *dev, struct regmap *regmap,
850 		      int irq, const char *name)
851 {
852 	struct bmc150_magn_data *data;
853 	struct iio_dev *indio_dev;
854 	int ret;
855 
856 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
857 	if (!indio_dev)
858 		return -ENOMEM;
859 
860 	data = iio_priv(indio_dev);
861 	dev_set_drvdata(dev, indio_dev);
862 	data->regmap = regmap;
863 	data->irq = irq;
864 	data->dev = dev;
865 
866 	data->regulators[0].supply = "vdd";
867 	data->regulators[1].supply = "vddio";
868 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
869 				      data->regulators);
870 	if (ret)
871 		return dev_err_probe(dev, ret, "failed to get regulators\n");
872 
873 	ret = iio_read_mount_matrix(dev, &data->orientation);
874 	if (ret)
875 		return ret;
876 
877 	mutex_init(&data->mutex);
878 
879 	ret = bmc150_magn_init(data);
880 	if (ret < 0)
881 		return ret;
882 
883 	indio_dev->channels = bmc150_magn_channels;
884 	indio_dev->num_channels = ARRAY_SIZE(bmc150_magn_channels);
885 	indio_dev->available_scan_masks = bmc150_magn_scan_masks;
886 	indio_dev->name = name;
887 	indio_dev->modes = INDIO_DIRECT_MODE;
888 	indio_dev->info = &bmc150_magn_info;
889 
890 	if (irq > 0) {
891 		data->dready_trig = devm_iio_trigger_alloc(dev,
892 							   "%s-dev%d",
893 							   indio_dev->name,
894 							   iio_device_id(indio_dev));
895 		if (!data->dready_trig) {
896 			ret = -ENOMEM;
897 			dev_err(dev, "iio trigger alloc failed\n");
898 			goto err_poweroff;
899 		}
900 
901 		data->dready_trig->ops = &bmc150_magn_trigger_ops;
902 		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
903 		ret = iio_trigger_register(data->dready_trig);
904 		if (ret) {
905 			dev_err(dev, "iio trigger register failed\n");
906 			goto err_poweroff;
907 		}
908 
909 		ret = request_threaded_irq(irq,
910 					   iio_trigger_generic_data_rdy_poll,
911 					   NULL,
912 					   IRQF_TRIGGER_RISING | IRQF_ONESHOT,
913 					   "bmc150_magn_event",
914 					   data->dready_trig);
915 		if (ret < 0) {
916 			dev_err(dev, "request irq %d failed\n", irq);
917 			goto err_trigger_unregister;
918 		}
919 	}
920 
921 	ret = iio_triggered_buffer_setup(indio_dev,
922 					 iio_pollfunc_store_time,
923 					 bmc150_magn_trigger_handler,
924 					 &bmc150_magn_buffer_setup_ops);
925 	if (ret < 0) {
926 		dev_err(dev, "iio triggered buffer setup failed\n");
927 		goto err_free_irq;
928 	}
929 
930 	ret = pm_runtime_set_active(dev);
931 	if (ret)
932 		goto err_buffer_cleanup;
933 
934 	pm_runtime_enable(dev);
935 	pm_runtime_set_autosuspend_delay(dev,
936 					 BMC150_MAGN_AUTO_SUSPEND_DELAY_MS);
937 	pm_runtime_use_autosuspend(dev);
938 
939 	ret = iio_device_register(indio_dev);
940 	if (ret < 0) {
941 		dev_err(dev, "unable to register iio device\n");
942 		goto err_pm_cleanup;
943 	}
944 
945 	dev_dbg(dev, "Registered device %s\n", name);
946 	return 0;
947 
948 err_pm_cleanup:
949 	pm_runtime_dont_use_autosuspend(dev);
950 	pm_runtime_disable(dev);
951 err_buffer_cleanup:
952 	iio_triggered_buffer_cleanup(indio_dev);
953 err_free_irq:
954 	if (irq > 0)
955 		free_irq(irq, data->dready_trig);
956 err_trigger_unregister:
957 	if (data->dready_trig)
958 		iio_trigger_unregister(data->dready_trig);
959 err_poweroff:
960 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
961 	return ret;
962 }
963 EXPORT_SYMBOL_NS(bmc150_magn_probe, "IIO_BMC150_MAGN");
964 
965 void bmc150_magn_remove(struct device *dev)
966 {
967 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
968 	struct bmc150_magn_data *data = iio_priv(indio_dev);
969 
970 	iio_device_unregister(indio_dev);
971 
972 	pm_runtime_disable(dev);
973 	pm_runtime_set_suspended(dev);
974 
975 	iio_triggered_buffer_cleanup(indio_dev);
976 
977 	if (data->irq > 0)
978 		free_irq(data->irq, data->dready_trig);
979 
980 	if (data->dready_trig)
981 		iio_trigger_unregister(data->dready_trig);
982 
983 	mutex_lock(&data->mutex);
984 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
985 	mutex_unlock(&data->mutex);
986 
987 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
988 }
989 EXPORT_SYMBOL_NS(bmc150_magn_remove, "IIO_BMC150_MAGN");
990 
991 #ifdef CONFIG_PM
992 static int bmc150_magn_runtime_suspend(struct device *dev)
993 {
994 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
995 	struct bmc150_magn_data *data = iio_priv(indio_dev);
996 	int ret;
997 
998 	mutex_lock(&data->mutex);
999 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
1000 					 true);
1001 	mutex_unlock(&data->mutex);
1002 	if (ret < 0) {
1003 		dev_err(dev, "powering off device failed\n");
1004 		return ret;
1005 	}
1006 	return 0;
1007 }
1008 
1009 /*
1010  * Should be called with data->mutex held.
1011  */
1012 static int bmc150_magn_runtime_resume(struct device *dev)
1013 {
1014 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1015 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1016 
1017 	return bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
1018 					  true);
1019 }
1020 #endif
1021 
1022 #ifdef CONFIG_PM_SLEEP
1023 static int bmc150_magn_suspend(struct device *dev)
1024 {
1025 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1026 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1027 	int ret;
1028 
1029 	mutex_lock(&data->mutex);
1030 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
1031 					 true);
1032 	mutex_unlock(&data->mutex);
1033 
1034 	return ret;
1035 }
1036 
1037 static int bmc150_magn_resume(struct device *dev)
1038 {
1039 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1040 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1041 	int ret;
1042 
1043 	mutex_lock(&data->mutex);
1044 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
1045 					 true);
1046 	mutex_unlock(&data->mutex);
1047 
1048 	return ret;
1049 }
1050 #endif
1051 
1052 const struct dev_pm_ops bmc150_magn_pm_ops = {
1053 	SET_SYSTEM_SLEEP_PM_OPS(bmc150_magn_suspend, bmc150_magn_resume)
1054 	SET_RUNTIME_PM_OPS(bmc150_magn_runtime_suspend,
1055 			   bmc150_magn_runtime_resume, NULL)
1056 };
1057 EXPORT_SYMBOL_NS(bmc150_magn_pm_ops, "IIO_BMC150_MAGN");
1058 
1059 MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
1060 MODULE_LICENSE("GPL v2");
1061 MODULE_DESCRIPTION("BMC150 magnetometer core driver");
1062