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/acpi.h>
18 #include <linux/pm.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/buffer.h>
23 #include <linux/iio/events.h>
24 #include <linux/iio/trigger.h>
25 #include <linux/iio/trigger_consumer.h>
26 #include <linux/iio/triggered_buffer.h>
27 #include <linux/regmap.h>
28 
29 #include "bmc150_magn.h"
30 
31 #define BMC150_MAGN_DRV_NAME			"bmc150_magn"
32 #define BMC150_MAGN_IRQ_NAME			"bmc150_magn_event"
33 
34 #define BMC150_MAGN_REG_CHIP_ID			0x40
35 #define BMC150_MAGN_CHIP_ID_VAL			0x32
36 
37 #define BMC150_MAGN_REG_X_L			0x42
38 #define BMC150_MAGN_REG_X_M			0x43
39 #define BMC150_MAGN_REG_Y_L			0x44
40 #define BMC150_MAGN_REG_Y_M			0x45
41 #define BMC150_MAGN_SHIFT_XY_L			3
42 #define BMC150_MAGN_REG_Z_L			0x46
43 #define BMC150_MAGN_REG_Z_M			0x47
44 #define BMC150_MAGN_SHIFT_Z_L			1
45 #define BMC150_MAGN_REG_RHALL_L			0x48
46 #define BMC150_MAGN_REG_RHALL_M			0x49
47 #define BMC150_MAGN_SHIFT_RHALL_L		2
48 
49 #define BMC150_MAGN_REG_INT_STATUS		0x4A
50 
51 #define BMC150_MAGN_REG_POWER			0x4B
52 #define BMC150_MAGN_MASK_POWER_CTL		BIT(0)
53 
54 #define BMC150_MAGN_REG_OPMODE_ODR		0x4C
55 #define BMC150_MAGN_MASK_OPMODE			GENMASK(2, 1)
56 #define BMC150_MAGN_SHIFT_OPMODE		1
57 #define BMC150_MAGN_MODE_NORMAL			0x00
58 #define BMC150_MAGN_MODE_FORCED			0x01
59 #define BMC150_MAGN_MODE_SLEEP			0x03
60 #define BMC150_MAGN_MASK_ODR			GENMASK(5, 3)
61 #define BMC150_MAGN_SHIFT_ODR			3
62 
63 #define BMC150_MAGN_REG_INT			0x4D
64 
65 #define BMC150_MAGN_REG_INT_DRDY		0x4E
66 #define BMC150_MAGN_MASK_DRDY_EN		BIT(7)
67 #define BMC150_MAGN_SHIFT_DRDY_EN		7
68 #define BMC150_MAGN_MASK_DRDY_INT3		BIT(6)
69 #define BMC150_MAGN_MASK_DRDY_Z_EN		BIT(5)
70 #define BMC150_MAGN_MASK_DRDY_Y_EN		BIT(4)
71 #define BMC150_MAGN_MASK_DRDY_X_EN		BIT(3)
72 #define BMC150_MAGN_MASK_DRDY_DR_POLARITY	BIT(2)
73 #define BMC150_MAGN_MASK_DRDY_LATCHING		BIT(1)
74 #define BMC150_MAGN_MASK_DRDY_INT3_POLARITY	BIT(0)
75 
76 #define BMC150_MAGN_REG_LOW_THRESH		0x4F
77 #define BMC150_MAGN_REG_HIGH_THRESH		0x50
78 #define BMC150_MAGN_REG_REP_XY			0x51
79 #define BMC150_MAGN_REG_REP_Z			0x52
80 #define BMC150_MAGN_REG_REP_DATAMASK		GENMASK(7, 0)
81 
82 #define BMC150_MAGN_REG_TRIM_START		0x5D
83 #define BMC150_MAGN_REG_TRIM_END		0x71
84 
85 #define BMC150_MAGN_XY_OVERFLOW_VAL		-4096
86 #define BMC150_MAGN_Z_OVERFLOW_VAL		-16384
87 
88 /* Time from SUSPEND to SLEEP */
89 #define BMC150_MAGN_START_UP_TIME_MS		3
90 
91 #define BMC150_MAGN_AUTO_SUSPEND_DELAY_MS	2000
92 
93 #define BMC150_MAGN_REGVAL_TO_REPXY(regval) (((regval) * 2) + 1)
94 #define BMC150_MAGN_REGVAL_TO_REPZ(regval) ((regval) + 1)
95 #define BMC150_MAGN_REPXY_TO_REGVAL(rep) (((rep) - 1) / 2)
96 #define BMC150_MAGN_REPZ_TO_REGVAL(rep) ((rep) - 1)
97 
98 enum bmc150_magn_axis {
99 	AXIS_X,
100 	AXIS_Y,
101 	AXIS_Z,
102 	RHALL,
103 	AXIS_XYZ_MAX = RHALL,
104 	AXIS_XYZR_MAX,
105 };
106 
107 enum bmc150_magn_power_modes {
108 	BMC150_MAGN_POWER_MODE_SUSPEND,
109 	BMC150_MAGN_POWER_MODE_SLEEP,
110 	BMC150_MAGN_POWER_MODE_NORMAL,
111 };
112 
113 struct bmc150_magn_trim_regs {
114 	s8 x1;
115 	s8 y1;
116 	__le16 reserved1;
117 	u8 reserved2;
118 	__le16 z4;
119 	s8 x2;
120 	s8 y2;
121 	__le16 reserved3;
122 	__le16 z2;
123 	__le16 z1;
124 	__le16 xyz1;
125 	__le16 z3;
126 	s8 xy2;
127 	u8 xy1;
128 } __packed;
129 
130 struct bmc150_magn_data {
131 	struct device *dev;
132 	/*
133 	 * 1. Protect this structure.
134 	 * 2. Serialize sequences that power on/off the device and access HW.
135 	 */
136 	struct mutex mutex;
137 	struct regmap *regmap;
138 	struct iio_mount_matrix orientation;
139 	/* 4 x 32 bits for x, y z, 4 bytes align, 64 bits timestamp */
140 	s32 buffer[6];
141 	struct iio_trigger *dready_trig;
142 	bool dready_trigger_on;
143 	int max_odr;
144 	int irq;
145 };
146 
147 static const struct {
148 	int freq;
149 	u8 reg_val;
150 } bmc150_magn_samp_freq_table[] = { {2, 0x01},
151 				    {6, 0x02},
152 				    {8, 0x03},
153 				    {10, 0x00},
154 				    {15, 0x04},
155 				    {20, 0x05},
156 				    {25, 0x06},
157 				    {30, 0x07} };
158 
159 enum bmc150_magn_presets {
160 	LOW_POWER_PRESET,
161 	REGULAR_PRESET,
162 	ENHANCED_REGULAR_PRESET,
163 	HIGH_ACCURACY_PRESET
164 };
165 
166 static const struct bmc150_magn_preset {
167 	u8 rep_xy;
168 	u8 rep_z;
169 	u8 odr;
170 } bmc150_magn_presets_table[] = {
171 	[LOW_POWER_PRESET] = {3, 3, 10},
172 	[REGULAR_PRESET] =  {9, 15, 10},
173 	[ENHANCED_REGULAR_PRESET] =  {15, 27, 10},
174 	[HIGH_ACCURACY_PRESET] =  {47, 83, 20},
175 };
176 
177 #define BMC150_MAGN_DEFAULT_PRESET REGULAR_PRESET
178 
179 static bool bmc150_magn_is_writeable_reg(struct device *dev, unsigned int reg)
180 {
181 	switch (reg) {
182 	case BMC150_MAGN_REG_POWER:
183 	case BMC150_MAGN_REG_OPMODE_ODR:
184 	case BMC150_MAGN_REG_INT:
185 	case BMC150_MAGN_REG_INT_DRDY:
186 	case BMC150_MAGN_REG_LOW_THRESH:
187 	case BMC150_MAGN_REG_HIGH_THRESH:
188 	case BMC150_MAGN_REG_REP_XY:
189 	case BMC150_MAGN_REG_REP_Z:
190 		return true;
191 	default:
192 		return false;
193 	}
194 }
195 
196 static bool bmc150_magn_is_volatile_reg(struct device *dev, unsigned int reg)
197 {
198 	switch (reg) {
199 	case BMC150_MAGN_REG_X_L:
200 	case BMC150_MAGN_REG_X_M:
201 	case BMC150_MAGN_REG_Y_L:
202 	case BMC150_MAGN_REG_Y_M:
203 	case BMC150_MAGN_REG_Z_L:
204 	case BMC150_MAGN_REG_Z_M:
205 	case BMC150_MAGN_REG_RHALL_L:
206 	case BMC150_MAGN_REG_RHALL_M:
207 	case BMC150_MAGN_REG_INT_STATUS:
208 		return true;
209 	default:
210 		return false;
211 	}
212 }
213 
214 const struct regmap_config bmc150_magn_regmap_config = {
215 	.reg_bits = 8,
216 	.val_bits = 8,
217 
218 	.max_register = BMC150_MAGN_REG_TRIM_END,
219 	.cache_type = REGCACHE_RBTREE,
220 
221 	.writeable_reg = bmc150_magn_is_writeable_reg,
222 	.volatile_reg = bmc150_magn_is_volatile_reg,
223 };
224 EXPORT_SYMBOL(bmc150_magn_regmap_config);
225 
226 static int bmc150_magn_set_power_mode(struct bmc150_magn_data *data,
227 				      enum bmc150_magn_power_modes mode,
228 				      bool state)
229 {
230 	int ret;
231 
232 	switch (mode) {
233 	case BMC150_MAGN_POWER_MODE_SUSPEND:
234 		ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_POWER,
235 					 BMC150_MAGN_MASK_POWER_CTL, !state);
236 		if (ret < 0)
237 			return ret;
238 		usleep_range(BMC150_MAGN_START_UP_TIME_MS * 1000, 20000);
239 		return 0;
240 	case BMC150_MAGN_POWER_MODE_SLEEP:
241 		return regmap_update_bits(data->regmap,
242 					  BMC150_MAGN_REG_OPMODE_ODR,
243 					  BMC150_MAGN_MASK_OPMODE,
244 					  BMC150_MAGN_MODE_SLEEP <<
245 					  BMC150_MAGN_SHIFT_OPMODE);
246 	case BMC150_MAGN_POWER_MODE_NORMAL:
247 		return regmap_update_bits(data->regmap,
248 					  BMC150_MAGN_REG_OPMODE_ODR,
249 					  BMC150_MAGN_MASK_OPMODE,
250 					  BMC150_MAGN_MODE_NORMAL <<
251 					  BMC150_MAGN_SHIFT_OPMODE);
252 	}
253 
254 	return -EINVAL;
255 }
256 
257 static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
258 {
259 #ifdef CONFIG_PM
260 	int ret;
261 
262 	if (on) {
263 		ret = pm_runtime_get_sync(data->dev);
264 	} else {
265 		pm_runtime_mark_last_busy(data->dev);
266 		ret = pm_runtime_put_autosuspend(data->dev);
267 	}
268 
269 	if (ret < 0) {
270 		dev_err(data->dev,
271 			"failed to change power state to %d\n", on);
272 		if (on)
273 			pm_runtime_put_noidle(data->dev);
274 
275 		return ret;
276 	}
277 #endif
278 
279 	return 0;
280 }
281 
282 static int bmc150_magn_get_odr(struct bmc150_magn_data *data, int *val)
283 {
284 	int ret, reg_val;
285 	u8 i, odr_val;
286 
287 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_OPMODE_ODR, &reg_val);
288 	if (ret < 0)
289 		return ret;
290 	odr_val = (reg_val & BMC150_MAGN_MASK_ODR) >> BMC150_MAGN_SHIFT_ODR;
291 
292 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++)
293 		if (bmc150_magn_samp_freq_table[i].reg_val == odr_val) {
294 			*val = bmc150_magn_samp_freq_table[i].freq;
295 			return 0;
296 		}
297 
298 	return -EINVAL;
299 }
300 
301 static int bmc150_magn_set_odr(struct bmc150_magn_data *data, int val)
302 {
303 	int ret;
304 	u8 i;
305 
306 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
307 		if (bmc150_magn_samp_freq_table[i].freq == val) {
308 			ret = regmap_update_bits(data->regmap,
309 						 BMC150_MAGN_REG_OPMODE_ODR,
310 						 BMC150_MAGN_MASK_ODR,
311 						 bmc150_magn_samp_freq_table[i].
312 						 reg_val <<
313 						 BMC150_MAGN_SHIFT_ODR);
314 			if (ret < 0)
315 				return ret;
316 			return 0;
317 		}
318 	}
319 
320 	return -EINVAL;
321 }
322 
323 static int bmc150_magn_set_max_odr(struct bmc150_magn_data *data, int rep_xy,
324 				   int rep_z, int odr)
325 {
326 	int ret, reg_val, max_odr;
327 
328 	if (rep_xy <= 0) {
329 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
330 				  &reg_val);
331 		if (ret < 0)
332 			return ret;
333 		rep_xy = BMC150_MAGN_REGVAL_TO_REPXY(reg_val);
334 	}
335 	if (rep_z <= 0) {
336 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
337 				  &reg_val);
338 		if (ret < 0)
339 			return ret;
340 		rep_z = BMC150_MAGN_REGVAL_TO_REPZ(reg_val);
341 	}
342 	if (odr <= 0) {
343 		ret = bmc150_magn_get_odr(data, &odr);
344 		if (ret < 0)
345 			return ret;
346 	}
347 	/* the maximum selectable read-out frequency from datasheet */
348 	max_odr = 1000000 / (145 * rep_xy + 500 * rep_z + 980);
349 	if (odr > max_odr) {
350 		dev_err(data->dev,
351 			"Can't set oversampling with sampling freq %d\n",
352 			odr);
353 		return -EINVAL;
354 	}
355 	data->max_odr = max_odr;
356 
357 	return 0;
358 }
359 
360 static s32 bmc150_magn_compensate_x(struct bmc150_magn_trim_regs *tregs, s16 x,
361 				    u16 rhall)
362 {
363 	s16 val;
364 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
365 
366 	if (x == BMC150_MAGN_XY_OVERFLOW_VAL)
367 		return S32_MIN;
368 
369 	if (!rhall)
370 		rhall = xyz1;
371 
372 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
373 	val = ((s16)((((s32)x) * ((((((((s32)tregs->xy2) * ((((s32)val) *
374 	      ((s32)val)) >> 7)) + (((s32)val) *
375 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
376 	      ((s32)(((s16)tregs->x2) + ((s16)0xA0)))) >> 12)) >> 13)) +
377 	      (((s16)tregs->x1) << 3);
378 
379 	return (s32)val;
380 }
381 
382 static s32 bmc150_magn_compensate_y(struct bmc150_magn_trim_regs *tregs, s16 y,
383 				    u16 rhall)
384 {
385 	s16 val;
386 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
387 
388 	if (y == BMC150_MAGN_XY_OVERFLOW_VAL)
389 		return S32_MIN;
390 
391 	if (!rhall)
392 		rhall = xyz1;
393 
394 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
395 	val = ((s16)((((s32)y) * ((((((((s32)tregs->xy2) * ((((s32)val) *
396 	      ((s32)val)) >> 7)) + (((s32)val) *
397 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
398 	      ((s32)(((s16)tregs->y2) + ((s16)0xA0)))) >> 12)) >> 13)) +
399 	      (((s16)tregs->y1) << 3);
400 
401 	return (s32)val;
402 }
403 
404 static s32 bmc150_magn_compensate_z(struct bmc150_magn_trim_regs *tregs, s16 z,
405 				    u16 rhall)
406 {
407 	s32 val;
408 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
409 	u16 z1 = le16_to_cpu(tregs->z1);
410 	s16 z2 = le16_to_cpu(tregs->z2);
411 	s16 z3 = le16_to_cpu(tregs->z3);
412 	s16 z4 = le16_to_cpu(tregs->z4);
413 
414 	if (z == BMC150_MAGN_Z_OVERFLOW_VAL)
415 		return S32_MIN;
416 
417 	val = (((((s32)(z - z4)) << 15) - ((((s32)z3) * ((s32)(((s16)rhall) -
418 	      ((s16)xyz1)))) >> 2)) / (z2 + ((s16)(((((s32)z1) *
419 	      ((((s16)rhall) << 1))) + (1 << 15)) >> 16))));
420 
421 	return val;
422 }
423 
424 static int bmc150_magn_read_xyz(struct bmc150_magn_data *data, s32 *buffer)
425 {
426 	int ret;
427 	__le16 values[AXIS_XYZR_MAX];
428 	s16 raw_x, raw_y, raw_z;
429 	u16 rhall;
430 	struct bmc150_magn_trim_regs tregs;
431 
432 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_X_L,
433 			       values, sizeof(values));
434 	if (ret < 0)
435 		return ret;
436 
437 	raw_x = (s16)le16_to_cpu(values[AXIS_X]) >> BMC150_MAGN_SHIFT_XY_L;
438 	raw_y = (s16)le16_to_cpu(values[AXIS_Y]) >> BMC150_MAGN_SHIFT_XY_L;
439 	raw_z = (s16)le16_to_cpu(values[AXIS_Z]) >> BMC150_MAGN_SHIFT_Z_L;
440 	rhall = le16_to_cpu(values[RHALL]) >> BMC150_MAGN_SHIFT_RHALL_L;
441 
442 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_TRIM_START,
443 			       &tregs, sizeof(tregs));
444 	if (ret < 0)
445 		return ret;
446 
447 	buffer[AXIS_X] = bmc150_magn_compensate_x(&tregs, raw_x, rhall);
448 	buffer[AXIS_Y] = bmc150_magn_compensate_y(&tregs, raw_y, rhall);
449 	buffer[AXIS_Z] = bmc150_magn_compensate_z(&tregs, raw_z, rhall);
450 
451 	return 0;
452 }
453 
454 static int bmc150_magn_read_raw(struct iio_dev *indio_dev,
455 				struct iio_chan_spec const *chan,
456 				int *val, int *val2, long mask)
457 {
458 	struct bmc150_magn_data *data = iio_priv(indio_dev);
459 	int ret, tmp;
460 	s32 values[AXIS_XYZ_MAX];
461 
462 	switch (mask) {
463 	case IIO_CHAN_INFO_RAW:
464 		if (iio_buffer_enabled(indio_dev))
465 			return -EBUSY;
466 		mutex_lock(&data->mutex);
467 
468 		ret = bmc150_magn_set_power_state(data, true);
469 		if (ret < 0) {
470 			mutex_unlock(&data->mutex);
471 			return ret;
472 		}
473 
474 		ret = bmc150_magn_read_xyz(data, values);
475 		if (ret < 0) {
476 			bmc150_magn_set_power_state(data, false);
477 			mutex_unlock(&data->mutex);
478 			return ret;
479 		}
480 		*val = values[chan->scan_index];
481 
482 		ret = bmc150_magn_set_power_state(data, false);
483 		if (ret < 0) {
484 			mutex_unlock(&data->mutex);
485 			return ret;
486 		}
487 
488 		mutex_unlock(&data->mutex);
489 		return IIO_VAL_INT;
490 	case IIO_CHAN_INFO_SCALE:
491 		/*
492 		 * The API/driver performs an off-chip temperature
493 		 * compensation and outputs x/y/z magnetic field data in
494 		 * 16 LSB/uT to the upper application layer.
495 		 */
496 		*val = 0;
497 		*val2 = 625;
498 		return IIO_VAL_INT_PLUS_MICRO;
499 	case IIO_CHAN_INFO_SAMP_FREQ:
500 		ret = bmc150_magn_get_odr(data, val);
501 		if (ret < 0)
502 			return ret;
503 		return IIO_VAL_INT;
504 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
505 		switch (chan->channel2) {
506 		case IIO_MOD_X:
507 		case IIO_MOD_Y:
508 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
509 					  &tmp);
510 			if (ret < 0)
511 				return ret;
512 			*val = BMC150_MAGN_REGVAL_TO_REPXY(tmp);
513 			return IIO_VAL_INT;
514 		case IIO_MOD_Z:
515 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
516 					  &tmp);
517 			if (ret < 0)
518 				return ret;
519 			*val = BMC150_MAGN_REGVAL_TO_REPZ(tmp);
520 			return IIO_VAL_INT;
521 		default:
522 			return -EINVAL;
523 		}
524 	default:
525 		return -EINVAL;
526 	}
527 }
528 
529 static int bmc150_magn_write_raw(struct iio_dev *indio_dev,
530 				 struct iio_chan_spec const *chan,
531 				 int val, int val2, long mask)
532 {
533 	struct bmc150_magn_data *data = iio_priv(indio_dev);
534 	int ret;
535 
536 	switch (mask) {
537 	case IIO_CHAN_INFO_SAMP_FREQ:
538 		if (val > data->max_odr)
539 			return -EINVAL;
540 		mutex_lock(&data->mutex);
541 		ret = bmc150_magn_set_odr(data, val);
542 		mutex_unlock(&data->mutex);
543 		return ret;
544 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
545 		switch (chan->channel2) {
546 		case IIO_MOD_X:
547 		case IIO_MOD_Y:
548 			if (val < 1 || val > 511)
549 				return -EINVAL;
550 			mutex_lock(&data->mutex);
551 			ret = bmc150_magn_set_max_odr(data, val, 0, 0);
552 			if (ret < 0) {
553 				mutex_unlock(&data->mutex);
554 				return ret;
555 			}
556 			ret = regmap_update_bits(data->regmap,
557 						 BMC150_MAGN_REG_REP_XY,
558 						 BMC150_MAGN_REG_REP_DATAMASK,
559 						 BMC150_MAGN_REPXY_TO_REGVAL
560 						 (val));
561 			mutex_unlock(&data->mutex);
562 			return ret;
563 		case IIO_MOD_Z:
564 			if (val < 1 || val > 256)
565 				return -EINVAL;
566 			mutex_lock(&data->mutex);
567 			ret = bmc150_magn_set_max_odr(data, 0, val, 0);
568 			if (ret < 0) {
569 				mutex_unlock(&data->mutex);
570 				return ret;
571 			}
572 			ret = regmap_update_bits(data->regmap,
573 						 BMC150_MAGN_REG_REP_Z,
574 						 BMC150_MAGN_REG_REP_DATAMASK,
575 						 BMC150_MAGN_REPZ_TO_REGVAL
576 						 (val));
577 			mutex_unlock(&data->mutex);
578 			return ret;
579 		default:
580 			return -EINVAL;
581 		}
582 	default:
583 		return -EINVAL;
584 	}
585 }
586 
587 static ssize_t bmc150_magn_show_samp_freq_avail(struct device *dev,
588 						struct device_attribute *attr,
589 						char *buf)
590 {
591 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
592 	struct bmc150_magn_data *data = iio_priv(indio_dev);
593 	size_t len = 0;
594 	u8 i;
595 
596 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
597 		if (bmc150_magn_samp_freq_table[i].freq > data->max_odr)
598 			break;
599 		len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
600 				 bmc150_magn_samp_freq_table[i].freq);
601 	}
602 	/* replace last space with a newline */
603 	buf[len - 1] = '\n';
604 
605 	return len;
606 }
607 
608 static const struct iio_mount_matrix *
609 bmc150_magn_get_mount_matrix(const struct iio_dev *indio_dev,
610 			      const struct iio_chan_spec *chan)
611 {
612 	struct bmc150_magn_data *data = iio_priv(indio_dev);
613 
614 	return &data->orientation;
615 }
616 
617 static const struct iio_chan_spec_ext_info bmc150_magn_ext_info[] = {
618 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bmc150_magn_get_mount_matrix),
619 	{ }
620 };
621 
622 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(bmc150_magn_show_samp_freq_avail);
623 
624 static struct attribute *bmc150_magn_attributes[] = {
625 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
626 	NULL,
627 };
628 
629 static const struct attribute_group bmc150_magn_attrs_group = {
630 	.attrs = bmc150_magn_attributes,
631 };
632 
633 #define BMC150_MAGN_CHANNEL(_axis) {					\
634 	.type = IIO_MAGN,						\
635 	.modified = 1,							\
636 	.channel2 = IIO_MOD_##_axis,					\
637 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
638 			      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
639 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |	\
640 				    BIT(IIO_CHAN_INFO_SCALE),		\
641 	.scan_index = AXIS_##_axis,					\
642 	.scan_type = {							\
643 		.sign = 's',						\
644 		.realbits = 32,						\
645 		.storagebits = 32,					\
646 		.endianness = IIO_LE					\
647 	},								\
648 	.ext_info = bmc150_magn_ext_info,				\
649 }
650 
651 static const struct iio_chan_spec bmc150_magn_channels[] = {
652 	BMC150_MAGN_CHANNEL(X),
653 	BMC150_MAGN_CHANNEL(Y),
654 	BMC150_MAGN_CHANNEL(Z),
655 	IIO_CHAN_SOFT_TIMESTAMP(3),
656 };
657 
658 static const struct iio_info bmc150_magn_info = {
659 	.attrs = &bmc150_magn_attrs_group,
660 	.read_raw = bmc150_magn_read_raw,
661 	.write_raw = bmc150_magn_write_raw,
662 };
663 
664 static const unsigned long bmc150_magn_scan_masks[] = {
665 					BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
666 					0};
667 
668 static irqreturn_t bmc150_magn_trigger_handler(int irq, void *p)
669 {
670 	struct iio_poll_func *pf = p;
671 	struct iio_dev *indio_dev = pf->indio_dev;
672 	struct bmc150_magn_data *data = iio_priv(indio_dev);
673 	int ret;
674 
675 	mutex_lock(&data->mutex);
676 	ret = bmc150_magn_read_xyz(data, data->buffer);
677 	if (ret < 0)
678 		goto err;
679 
680 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
681 					   pf->timestamp);
682 
683 err:
684 	mutex_unlock(&data->mutex);
685 	iio_trigger_notify_done(indio_dev->trig);
686 
687 	return IRQ_HANDLED;
688 }
689 
690 static int bmc150_magn_init(struct bmc150_magn_data *data)
691 {
692 	int ret, chip_id;
693 	struct bmc150_magn_preset preset;
694 
695 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND,
696 					 false);
697 	if (ret < 0) {
698 		dev_err(data->dev,
699 			"Failed to bring up device from suspend mode\n");
700 		return ret;
701 	}
702 
703 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_CHIP_ID, &chip_id);
704 	if (ret < 0) {
705 		dev_err(data->dev, "Failed reading chip id\n");
706 		goto err_poweroff;
707 	}
708 	if (chip_id != BMC150_MAGN_CHIP_ID_VAL) {
709 		dev_err(data->dev, "Invalid chip id 0x%x\n", chip_id);
710 		ret = -ENODEV;
711 		goto err_poweroff;
712 	}
713 	dev_dbg(data->dev, "Chip id %x\n", chip_id);
714 
715 	preset = bmc150_magn_presets_table[BMC150_MAGN_DEFAULT_PRESET];
716 	ret = bmc150_magn_set_odr(data, preset.odr);
717 	if (ret < 0) {
718 		dev_err(data->dev, "Failed to set ODR to %d\n",
719 			preset.odr);
720 		goto err_poweroff;
721 	}
722 
723 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_XY,
724 			   BMC150_MAGN_REPXY_TO_REGVAL(preset.rep_xy));
725 	if (ret < 0) {
726 		dev_err(data->dev, "Failed to set REP XY to %d\n",
727 			preset.rep_xy);
728 		goto err_poweroff;
729 	}
730 
731 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_Z,
732 			   BMC150_MAGN_REPZ_TO_REGVAL(preset.rep_z));
733 	if (ret < 0) {
734 		dev_err(data->dev, "Failed to set REP Z to %d\n",
735 			preset.rep_z);
736 		goto err_poweroff;
737 	}
738 
739 	ret = bmc150_magn_set_max_odr(data, preset.rep_xy, preset.rep_z,
740 				      preset.odr);
741 	if (ret < 0)
742 		goto err_poweroff;
743 
744 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
745 					 true);
746 	if (ret < 0) {
747 		dev_err(data->dev, "Failed to power on device\n");
748 		goto err_poweroff;
749 	}
750 
751 	return 0;
752 
753 err_poweroff:
754 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
755 	return ret;
756 }
757 
758 static int bmc150_magn_reset_intr(struct bmc150_magn_data *data)
759 {
760 	int tmp;
761 
762 	/*
763 	 * Data Ready (DRDY) is always cleared after
764 	 * readout of data registers ends.
765 	 */
766 	return regmap_read(data->regmap, BMC150_MAGN_REG_X_L, &tmp);
767 }
768 
769 static void bmc150_magn_trig_reen(struct iio_trigger *trig)
770 {
771 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
772 	struct bmc150_magn_data *data = iio_priv(indio_dev);
773 	int ret;
774 
775 	if (!data->dready_trigger_on)
776 		return;
777 
778 	mutex_lock(&data->mutex);
779 	ret = bmc150_magn_reset_intr(data);
780 	mutex_unlock(&data->mutex);
781 	if (ret)
782 		dev_err(data->dev, "Failed to reset interrupt\n");
783 }
784 
785 static int bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger *trig,
786 						  bool state)
787 {
788 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
789 	struct bmc150_magn_data *data = iio_priv(indio_dev);
790 	int ret = 0;
791 
792 	mutex_lock(&data->mutex);
793 	if (state == data->dready_trigger_on)
794 		goto err_unlock;
795 
796 	ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_INT_DRDY,
797 				 BMC150_MAGN_MASK_DRDY_EN,
798 				 state << BMC150_MAGN_SHIFT_DRDY_EN);
799 	if (ret < 0)
800 		goto err_unlock;
801 
802 	data->dready_trigger_on = state;
803 
804 	if (state) {
805 		ret = bmc150_magn_reset_intr(data);
806 		if (ret < 0)
807 			goto err_unlock;
808 	}
809 	mutex_unlock(&data->mutex);
810 
811 	return 0;
812 
813 err_unlock:
814 	mutex_unlock(&data->mutex);
815 	return ret;
816 }
817 
818 static const struct iio_trigger_ops bmc150_magn_trigger_ops = {
819 	.set_trigger_state = bmc150_magn_data_rdy_trigger_set_state,
820 	.reenable = bmc150_magn_trig_reen,
821 };
822 
823 static int bmc150_magn_buffer_preenable(struct iio_dev *indio_dev)
824 {
825 	struct bmc150_magn_data *data = iio_priv(indio_dev);
826 
827 	return bmc150_magn_set_power_state(data, true);
828 }
829 
830 static int bmc150_magn_buffer_postdisable(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, false);
835 }
836 
837 static const struct iio_buffer_setup_ops bmc150_magn_buffer_setup_ops = {
838 	.preenable = bmc150_magn_buffer_preenable,
839 	.postdisable = bmc150_magn_buffer_postdisable,
840 };
841 
842 static const char *bmc150_magn_match_acpi_device(struct device *dev)
843 {
844 	const struct acpi_device_id *id;
845 
846 	id = acpi_match_device(dev->driver->acpi_match_table, dev);
847 	if (!id)
848 		return NULL;
849 
850 	return dev_name(dev);
851 }
852 
853 int bmc150_magn_probe(struct device *dev, struct regmap *regmap,
854 		      int irq, const char *name)
855 {
856 	struct bmc150_magn_data *data;
857 	struct iio_dev *indio_dev;
858 	int ret;
859 
860 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
861 	if (!indio_dev)
862 		return -ENOMEM;
863 
864 	data = iio_priv(indio_dev);
865 	dev_set_drvdata(dev, indio_dev);
866 	data->regmap = regmap;
867 	data->irq = irq;
868 	data->dev = dev;
869 
870 	ret = iio_read_mount_matrix(dev, "mount-matrix",
871 				&data->orientation);
872 	if (ret)
873 		return ret;
874 
875 	if (!name && ACPI_HANDLE(dev))
876 		name = bmc150_magn_match_acpi_device(dev);
877 
878 	mutex_init(&data->mutex);
879 
880 	ret = bmc150_magn_init(data);
881 	if (ret < 0)
882 		return ret;
883 
884 	indio_dev->channels = bmc150_magn_channels;
885 	indio_dev->num_channels = ARRAY_SIZE(bmc150_magn_channels);
886 	indio_dev->available_scan_masks = bmc150_magn_scan_masks;
887 	indio_dev->name = name;
888 	indio_dev->modes = INDIO_DIRECT_MODE;
889 	indio_dev->info = &bmc150_magn_info;
890 
891 	if (irq > 0) {
892 		data->dready_trig = devm_iio_trigger_alloc(dev,
893 							   "%s-dev%d",
894 							   indio_dev->name,
895 							   indio_dev->id);
896 		if (!data->dready_trig) {
897 			ret = -ENOMEM;
898 			dev_err(dev, "iio trigger alloc failed\n");
899 			goto err_poweroff;
900 		}
901 
902 		data->dready_trig->dev.parent = dev;
903 		data->dready_trig->ops = &bmc150_magn_trigger_ops;
904 		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
905 		ret = iio_trigger_register(data->dready_trig);
906 		if (ret) {
907 			dev_err(dev, "iio trigger register failed\n");
908 			goto err_poweroff;
909 		}
910 
911 		ret = request_threaded_irq(irq,
912 					   iio_trigger_generic_data_rdy_poll,
913 					   NULL,
914 					   IRQF_TRIGGER_RISING | IRQF_ONESHOT,
915 					   BMC150_MAGN_IRQ_NAME,
916 					   data->dready_trig);
917 		if (ret < 0) {
918 			dev_err(dev, "request irq %d failed\n", irq);
919 			goto err_trigger_unregister;
920 		}
921 	}
922 
923 	ret = iio_triggered_buffer_setup(indio_dev,
924 					 iio_pollfunc_store_time,
925 					 bmc150_magn_trigger_handler,
926 					 &bmc150_magn_buffer_setup_ops);
927 	if (ret < 0) {
928 		dev_err(dev, "iio triggered buffer setup failed\n");
929 		goto err_free_irq;
930 	}
931 
932 	ret = pm_runtime_set_active(dev);
933 	if (ret)
934 		goto err_buffer_cleanup;
935 
936 	pm_runtime_enable(dev);
937 	pm_runtime_set_autosuspend_delay(dev,
938 					 BMC150_MAGN_AUTO_SUSPEND_DELAY_MS);
939 	pm_runtime_use_autosuspend(dev);
940 
941 	ret = iio_device_register(indio_dev);
942 	if (ret < 0) {
943 		dev_err(dev, "unable to register iio device\n");
944 		goto err_buffer_cleanup;
945 	}
946 
947 	dev_dbg(dev, "Registered device %s\n", name);
948 	return 0;
949 
950 err_buffer_cleanup:
951 	iio_triggered_buffer_cleanup(indio_dev);
952 err_free_irq:
953 	if (irq > 0)
954 		free_irq(irq, data->dready_trig);
955 err_trigger_unregister:
956 	if (data->dready_trig)
957 		iio_trigger_unregister(data->dready_trig);
958 err_poweroff:
959 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
960 	return ret;
961 }
962 EXPORT_SYMBOL(bmc150_magn_probe);
963 
964 int bmc150_magn_remove(struct device *dev)
965 {
966 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
967 	struct bmc150_magn_data *data = iio_priv(indio_dev);
968 
969 	iio_device_unregister(indio_dev);
970 
971 	pm_runtime_disable(dev);
972 	pm_runtime_set_suspended(dev);
973 	pm_runtime_put_noidle(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 	return 0;
988 }
989 EXPORT_SYMBOL(bmc150_magn_remove);
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(bmc150_magn_pm_ops);
1058 
1059 MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
1060 MODULE_LICENSE("GPL v2");
1061 MODULE_DESCRIPTION("BMC150 magnetometer core driver");
1062