xref: /linux/drivers/iio/accel/bma400_core.c (revision 566ab427f827b0256d3e8ce0235d088e6a9c28bd)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Core IIO driver for Bosch BMA400 triaxial acceleration sensor.
4  *
5  * Copyright 2019 Dan Robertson <dan@dlrobertson.com>
6  *
7  * TODO:
8  *  - Support for power management
9  *  - Support events and interrupts
10  *  - Create channel for step count
11  *  - Create channel for sensor time
12  */
13 
14 #include <linux/bitfield.h>
15 #include <linux/bitops.h>
16 #include <linux/cleanup.h>
17 #include <linux/device.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/mutex.h>
21 #include <linux/regmap.h>
22 #include <linux/regulator/consumer.h>
23 #include <linux/slab.h>
24 
25 #include <linux/unaligned.h>
26 
27 #include <linux/iio/iio.h>
28 #include <linux/iio/buffer.h>
29 #include <linux/iio/events.h>
30 #include <linux/iio/sysfs.h>
31 #include <linux/iio/trigger.h>
32 #include <linux/iio/trigger_consumer.h>
33 #include <linux/iio/triggered_buffer.h>
34 
35 #include "bma400.h"
36 
37 /*
38  * The G-range selection may be one of 2g, 4g, 8, or 16g. The scale may
39  * be selected with the acc_range bits of the ACC_CONFIG1 register.
40  * NB: This buffer is populated in the device init.
41  */
42 static int bma400_scales[8];
43 
44 /*
45  * See the ACC_CONFIG1 section of the datasheet.
46  * NB: This buffer is populated in the device init.
47  */
48 static int bma400_sample_freqs[14];
49 
50 static const int bma400_osr_range[] = { 0, 1, 3 };
51 
52 static int tap_reset_timeout[BMA400_TAP_TIM_LIST_LEN] = {
53 	300000,
54 	400000,
55 	500000,
56 	600000
57 };
58 
59 static int tap_max2min_time[BMA400_TAP_TIM_LIST_LEN] = {
60 	30000,
61 	45000,
62 	60000,
63 	90000
64 };
65 
66 static int double_tap2_min_delay[BMA400_TAP_TIM_LIST_LEN] = {
67 	20000,
68 	40000,
69 	60000,
70 	80000
71 };
72 
73 /* See the ACC_CONFIG0 section of the datasheet */
74 enum bma400_power_mode {
75 	POWER_MODE_SLEEP   = 0x00,
76 	POWER_MODE_LOW     = 0x01,
77 	POWER_MODE_NORMAL  = 0x02,
78 	POWER_MODE_INVALID = 0x03,
79 };
80 
81 enum bma400_scan {
82 	BMA400_ACCL_X,
83 	BMA400_ACCL_Y,
84 	BMA400_ACCL_Z,
85 	BMA400_TEMP,
86 };
87 
88 struct bma400_sample_freq {
89 	int hz;
90 	int uhz;
91 };
92 
93 enum bma400_activity {
94 	BMA400_STILL,
95 	BMA400_WALKING,
96 	BMA400_RUNNING,
97 };
98 
99 struct bma400_data {
100 	struct device *dev;
101 	struct regmap *regmap;
102 	struct mutex mutex; /* data register lock */
103 	struct iio_mount_matrix orientation;
104 	enum bma400_power_mode power_mode;
105 	struct bma400_sample_freq sample_freq;
106 	int oversampling_ratio;
107 	int scale;
108 	struct iio_trigger *trig;
109 	int steps_enabled;
110 	bool step_event_en;
111 	bool activity_event_en;
112 	unsigned int generic_event_en;
113 	unsigned int tap_event_en_bitmask;
114 	/* Correct time stamp alignment */
115 	struct {
116 		__le16 buff[3];
117 		u8 temperature;
118 		s64 ts __aligned(8);
119 	} buffer __aligned(IIO_DMA_MINALIGN);
120 	__le16 status;
121 	__be16 duration;
122 };
123 
124 static bool bma400_is_writable_reg(struct device *dev, unsigned int reg)
125 {
126 	switch (reg) {
127 	case BMA400_CHIP_ID_REG:
128 	case BMA400_ERR_REG:
129 	case BMA400_STATUS_REG:
130 	case BMA400_X_AXIS_LSB_REG:
131 	case BMA400_X_AXIS_MSB_REG:
132 	case BMA400_Y_AXIS_LSB_REG:
133 	case BMA400_Y_AXIS_MSB_REG:
134 	case BMA400_Z_AXIS_LSB_REG:
135 	case BMA400_Z_AXIS_MSB_REG:
136 	case BMA400_SENSOR_TIME0:
137 	case BMA400_SENSOR_TIME1:
138 	case BMA400_SENSOR_TIME2:
139 	case BMA400_EVENT_REG:
140 	case BMA400_INT_STAT0_REG:
141 	case BMA400_INT_STAT1_REG:
142 	case BMA400_INT_STAT2_REG:
143 	case BMA400_TEMP_DATA_REG:
144 	case BMA400_FIFO_LENGTH0_REG:
145 	case BMA400_FIFO_LENGTH1_REG:
146 	case BMA400_FIFO_DATA_REG:
147 	case BMA400_STEP_CNT0_REG:
148 	case BMA400_STEP_CNT1_REG:
149 	case BMA400_STEP_CNT3_REG:
150 	case BMA400_STEP_STAT_REG:
151 		return false;
152 	default:
153 		return true;
154 	}
155 }
156 
157 static bool bma400_is_volatile_reg(struct device *dev, unsigned int reg)
158 {
159 	switch (reg) {
160 	case BMA400_ERR_REG:
161 	case BMA400_STATUS_REG:
162 	case BMA400_X_AXIS_LSB_REG:
163 	case BMA400_X_AXIS_MSB_REG:
164 	case BMA400_Y_AXIS_LSB_REG:
165 	case BMA400_Y_AXIS_MSB_REG:
166 	case BMA400_Z_AXIS_LSB_REG:
167 	case BMA400_Z_AXIS_MSB_REG:
168 	case BMA400_SENSOR_TIME0:
169 	case BMA400_SENSOR_TIME1:
170 	case BMA400_SENSOR_TIME2:
171 	case BMA400_EVENT_REG:
172 	case BMA400_INT_STAT0_REG:
173 	case BMA400_INT_STAT1_REG:
174 	case BMA400_INT_STAT2_REG:
175 	case BMA400_TEMP_DATA_REG:
176 	case BMA400_FIFO_LENGTH0_REG:
177 	case BMA400_FIFO_LENGTH1_REG:
178 	case BMA400_FIFO_DATA_REG:
179 	case BMA400_STEP_CNT0_REG:
180 	case BMA400_STEP_CNT1_REG:
181 	case BMA400_STEP_CNT3_REG:
182 	case BMA400_STEP_STAT_REG:
183 		return true;
184 	default:
185 		return false;
186 	}
187 }
188 
189 const struct regmap_config bma400_regmap_config = {
190 	.reg_bits = 8,
191 	.val_bits = 8,
192 	.max_register = BMA400_CMD_REG,
193 	.cache_type = REGCACHE_RBTREE,
194 	.writeable_reg = bma400_is_writable_reg,
195 	.volatile_reg = bma400_is_volatile_reg,
196 };
197 EXPORT_SYMBOL_NS(bma400_regmap_config, IIO_BMA400);
198 
199 static const struct iio_mount_matrix *
200 bma400_accel_get_mount_matrix(const struct iio_dev *indio_dev,
201 			      const struct iio_chan_spec *chan)
202 {
203 	struct bma400_data *data = iio_priv(indio_dev);
204 
205 	return &data->orientation;
206 }
207 
208 static const struct iio_chan_spec_ext_info bma400_ext_info[] = {
209 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bma400_accel_get_mount_matrix),
210 	{ }
211 };
212 
213 static const struct iio_event_spec bma400_step_detect_event = {
214 	.type = IIO_EV_TYPE_CHANGE,
215 	.dir = IIO_EV_DIR_NONE,
216 	.mask_separate = BIT(IIO_EV_INFO_ENABLE),
217 };
218 
219 static const struct iio_event_spec bma400_activity_event = {
220 	.type = IIO_EV_TYPE_CHANGE,
221 	.dir = IIO_EV_DIR_NONE,
222 	.mask_shared_by_type = BIT(IIO_EV_INFO_ENABLE),
223 };
224 
225 static const struct iio_event_spec bma400_accel_event[] = {
226 	{
227 		.type = IIO_EV_TYPE_MAG,
228 		.dir = IIO_EV_DIR_FALLING,
229 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
230 				       BIT(IIO_EV_INFO_PERIOD) |
231 				       BIT(IIO_EV_INFO_HYSTERESIS) |
232 				       BIT(IIO_EV_INFO_ENABLE),
233 	},
234 	{
235 		.type = IIO_EV_TYPE_MAG,
236 		.dir = IIO_EV_DIR_RISING,
237 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
238 				       BIT(IIO_EV_INFO_PERIOD) |
239 				       BIT(IIO_EV_INFO_HYSTERESIS) |
240 				       BIT(IIO_EV_INFO_ENABLE),
241 	},
242 	{
243 		.type = IIO_EV_TYPE_GESTURE,
244 		.dir = IIO_EV_DIR_SINGLETAP,
245 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
246 				       BIT(IIO_EV_INFO_ENABLE) |
247 				       BIT(IIO_EV_INFO_RESET_TIMEOUT),
248 	},
249 	{
250 		.type = IIO_EV_TYPE_GESTURE,
251 		.dir = IIO_EV_DIR_DOUBLETAP,
252 		.mask_shared_by_type = BIT(IIO_EV_INFO_VALUE) |
253 				       BIT(IIO_EV_INFO_ENABLE) |
254 				       BIT(IIO_EV_INFO_RESET_TIMEOUT) |
255 				       BIT(IIO_EV_INFO_TAP2_MIN_DELAY),
256 	},
257 };
258 
259 static int usec_to_tapreg_raw(int usec, const int *time_list)
260 {
261 	int index;
262 
263 	for (index = 0; index < BMA400_TAP_TIM_LIST_LEN; index++) {
264 		if (usec == time_list[index])
265 			return index;
266 	}
267 	return -EINVAL;
268 }
269 
270 static ssize_t in_accel_gesture_tap_maxtomin_time_show(struct device *dev,
271 						       struct device_attribute *attr,
272 						       char *buf)
273 {
274 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
275 	struct bma400_data *data = iio_priv(indio_dev);
276 	int ret, reg_val, raw, vals[2];
277 
278 	ret = regmap_read(data->regmap, BMA400_TAP_CONFIG1, &reg_val);
279 	if (ret)
280 		return ret;
281 
282 	raw = FIELD_GET(BMA400_TAP_TICSTH_MSK, reg_val);
283 	vals[0] = 0;
284 	vals[1] = tap_max2min_time[raw];
285 
286 	return iio_format_value(buf, IIO_VAL_INT_PLUS_MICRO, 2, vals);
287 }
288 
289 static ssize_t in_accel_gesture_tap_maxtomin_time_store(struct device *dev,
290 							struct device_attribute *attr,
291 							const char *buf, size_t len)
292 {
293 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
294 	struct bma400_data *data = iio_priv(indio_dev);
295 	int ret, val_int, val_fract, raw;
296 
297 	ret = iio_str_to_fixpoint(buf, 100000, &val_int, &val_fract);
298 	if (ret)
299 		return ret;
300 
301 	raw = usec_to_tapreg_raw(val_fract, tap_max2min_time);
302 	if (raw < 0)
303 		return -EINVAL;
304 
305 	ret = regmap_update_bits(data->regmap, BMA400_TAP_CONFIG1,
306 				 BMA400_TAP_TICSTH_MSK,
307 				 FIELD_PREP(BMA400_TAP_TICSTH_MSK, raw));
308 	if (ret)
309 		return ret;
310 
311 	return len;
312 }
313 
314 static IIO_DEVICE_ATTR_RW(in_accel_gesture_tap_maxtomin_time, 0);
315 
316 /*
317  * Tap interrupts works with 200 Hz input data rate and the time based tap
318  * controls are in the terms of data samples so the below calculation is
319  * used to convert the configuration values into seconds.
320  * e.g.:
321  * 60 data samples * 0.005 ms = 0.3 seconds.
322  * 80 data samples * 0.005 ms = 0.4 seconds.
323  */
324 
325 /* quiet configuration values in seconds */
326 static IIO_CONST_ATTR(in_accel_gesture_tap_reset_timeout_available,
327 		      "0.3 0.4 0.5 0.6");
328 
329 /* tics_th configuration values in seconds */
330 static IIO_CONST_ATTR(in_accel_gesture_tap_maxtomin_time_available,
331 		      "0.03 0.045 0.06 0.09");
332 
333 /* quiet_dt configuration values in seconds */
334 static IIO_CONST_ATTR(in_accel_gesture_doubletap_tap2_min_delay_available,
335 		      "0.02 0.04 0.06 0.08");
336 
337 /* List of sensitivity values available to configure tap interrupts */
338 static IIO_CONST_ATTR(in_accel_gesture_tap_value_available, "0 1 2 3 4 5 6 7");
339 
340 static struct attribute *bma400_event_attributes[] = {
341 	&iio_const_attr_in_accel_gesture_tap_value_available.dev_attr.attr,
342 	&iio_const_attr_in_accel_gesture_tap_reset_timeout_available.dev_attr.attr,
343 	&iio_const_attr_in_accel_gesture_tap_maxtomin_time_available.dev_attr.attr,
344 	&iio_const_attr_in_accel_gesture_doubletap_tap2_min_delay_available.dev_attr.attr,
345 	&iio_dev_attr_in_accel_gesture_tap_maxtomin_time.dev_attr.attr,
346 	NULL
347 };
348 
349 static const struct attribute_group bma400_event_attribute_group = {
350 	.attrs = bma400_event_attributes,
351 };
352 
353 #define BMA400_ACC_CHANNEL(_index, _axis) { \
354 	.type = IIO_ACCEL, \
355 	.modified = 1, \
356 	.channel2 = IIO_MOD_##_axis, \
357 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
358 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
359 		BIT(IIO_CHAN_INFO_SCALE) | \
360 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
361 	.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SAMP_FREQ) | \
362 		BIT(IIO_CHAN_INFO_SCALE) | \
363 		BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
364 	.ext_info = bma400_ext_info, \
365 	.scan_index = _index,	\
366 	.scan_type = {		\
367 		.sign = 's',	\
368 		.realbits = 12,		\
369 		.storagebits = 16,	\
370 		.endianness = IIO_LE,	\
371 	},				\
372 	.event_spec = bma400_accel_event,			\
373 	.num_event_specs = ARRAY_SIZE(bma400_accel_event)	\
374 }
375 
376 #define BMA400_ACTIVITY_CHANNEL(_chan2) {	\
377 	.type = IIO_ACTIVITY,			\
378 	.modified = 1,				\
379 	.channel2 = _chan2,			\
380 	.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),	\
381 	.scan_index = -1, /* No buffer support */		\
382 	.event_spec = &bma400_activity_event,			\
383 	.num_event_specs = 1,					\
384 }
385 
386 static const struct iio_chan_spec bma400_channels[] = {
387 	BMA400_ACC_CHANNEL(0, X),
388 	BMA400_ACC_CHANNEL(1, Y),
389 	BMA400_ACC_CHANNEL(2, Z),
390 	{
391 		.type = IIO_TEMP,
392 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
393 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ),
394 		.scan_index = 3,
395 		.scan_type = {
396 			.sign = 's',
397 			.realbits = 8,
398 			.storagebits = 8,
399 			.endianness = IIO_LE,
400 		},
401 	},
402 	{
403 		.type = IIO_STEPS,
404 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
405 				      BIT(IIO_CHAN_INFO_ENABLE),
406 		.scan_index = -1, /* No buffer support */
407 		.event_spec = &bma400_step_detect_event,
408 		.num_event_specs = 1,
409 	},
410 	BMA400_ACTIVITY_CHANNEL(IIO_MOD_STILL),
411 	BMA400_ACTIVITY_CHANNEL(IIO_MOD_WALKING),
412 	BMA400_ACTIVITY_CHANNEL(IIO_MOD_RUNNING),
413 	IIO_CHAN_SOFT_TIMESTAMP(4),
414 };
415 
416 static int bma400_get_temp_reg(struct bma400_data *data, int *val, int *val2)
417 {
418 	unsigned int raw_temp;
419 	int host_temp;
420 	int ret;
421 
422 	if (data->power_mode == POWER_MODE_SLEEP)
423 		return -EBUSY;
424 
425 	ret = regmap_read(data->regmap, BMA400_TEMP_DATA_REG, &raw_temp);
426 	if (ret)
427 		return ret;
428 
429 	host_temp = sign_extend32(raw_temp, 7);
430 	/*
431 	 * The formula for the TEMP_DATA register in the datasheet
432 	 * is: x * 0.5 + 23
433 	 */
434 	*val = (host_temp >> 1) + 23;
435 	*val2 = (host_temp & 0x1) * 500000;
436 	return IIO_VAL_INT_PLUS_MICRO;
437 }
438 
439 static int bma400_get_accel_reg(struct bma400_data *data,
440 				const struct iio_chan_spec *chan,
441 				int *val)
442 {
443 	__le16 raw_accel;
444 	int lsb_reg;
445 	int ret;
446 
447 	if (data->power_mode == POWER_MODE_SLEEP)
448 		return -EBUSY;
449 
450 	switch (chan->channel2) {
451 	case IIO_MOD_X:
452 		lsb_reg = BMA400_X_AXIS_LSB_REG;
453 		break;
454 	case IIO_MOD_Y:
455 		lsb_reg = BMA400_Y_AXIS_LSB_REG;
456 		break;
457 	case IIO_MOD_Z:
458 		lsb_reg = BMA400_Z_AXIS_LSB_REG;
459 		break;
460 	default:
461 		dev_err(data->dev, "invalid axis channel modifier\n");
462 		return -EINVAL;
463 	}
464 
465 	/* bulk read two registers, with the base being the LSB register */
466 	ret = regmap_bulk_read(data->regmap, lsb_reg, &raw_accel,
467 			       sizeof(raw_accel));
468 	if (ret)
469 		return ret;
470 
471 	*val = sign_extend32(le16_to_cpu(raw_accel), 11);
472 	return IIO_VAL_INT;
473 }
474 
475 static void bma400_output_data_rate_from_raw(int raw, unsigned int *val,
476 					     unsigned int *val2)
477 {
478 	*val = BMA400_ACC_ODR_MAX_HZ >> (BMA400_ACC_ODR_MAX_RAW - raw);
479 	if (raw > BMA400_ACC_ODR_MIN_RAW)
480 		*val2 = 0;
481 	else
482 		*val2 = 500000;
483 }
484 
485 static int bma400_get_accel_output_data_rate(struct bma400_data *data)
486 {
487 	unsigned int val;
488 	unsigned int odr;
489 	int ret;
490 
491 	switch (data->power_mode) {
492 	case POWER_MODE_LOW:
493 		/*
494 		 * Runs at a fixed rate in low-power mode. See section 4.3
495 		 * in the datasheet.
496 		 */
497 		bma400_output_data_rate_from_raw(BMA400_ACC_ODR_LP_RAW,
498 						 &data->sample_freq.hz,
499 						 &data->sample_freq.uhz);
500 		return 0;
501 	case POWER_MODE_NORMAL:
502 		/*
503 		 * In normal mode the ODR can be found in the ACC_CONFIG1
504 		 * register.
505 		 */
506 		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
507 		if (ret)
508 			goto error;
509 
510 		odr = val & BMA400_ACC_ODR_MASK;
511 		if (odr < BMA400_ACC_ODR_MIN_RAW ||
512 		    odr > BMA400_ACC_ODR_MAX_RAW) {
513 			ret = -EINVAL;
514 			goto error;
515 		}
516 
517 		bma400_output_data_rate_from_raw(odr, &data->sample_freq.hz,
518 						 &data->sample_freq.uhz);
519 		return 0;
520 	case POWER_MODE_SLEEP:
521 		data->sample_freq.hz = 0;
522 		data->sample_freq.uhz = 0;
523 		return 0;
524 	default:
525 		ret = 0;
526 		goto error;
527 	}
528 error:
529 	data->sample_freq.hz = -1;
530 	data->sample_freq.uhz = -1;
531 	return ret;
532 }
533 
534 static int bma400_set_accel_output_data_rate(struct bma400_data *data,
535 					     int hz, int uhz)
536 {
537 	unsigned int idx;
538 	unsigned int odr;
539 	unsigned int val;
540 	int ret;
541 
542 	if (hz >= BMA400_ACC_ODR_MIN_WHOLE_HZ) {
543 		if (uhz || hz > BMA400_ACC_ODR_MAX_HZ)
544 			return -EINVAL;
545 
546 		/* Note this works because MIN_WHOLE_HZ is odd */
547 		idx = __ffs(hz);
548 
549 		if (hz >> idx != BMA400_ACC_ODR_MIN_WHOLE_HZ)
550 			return -EINVAL;
551 
552 		idx += BMA400_ACC_ODR_MIN_RAW + 1;
553 	} else if (hz == BMA400_ACC_ODR_MIN_HZ && uhz == 500000) {
554 		idx = BMA400_ACC_ODR_MIN_RAW;
555 	} else {
556 		return -EINVAL;
557 	}
558 
559 	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
560 	if (ret)
561 		return ret;
562 
563 	/* preserve the range and normal mode osr */
564 	odr = (~BMA400_ACC_ODR_MASK & val) | idx;
565 
566 	ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG, odr);
567 	if (ret)
568 		return ret;
569 
570 	bma400_output_data_rate_from_raw(idx, &data->sample_freq.hz,
571 					 &data->sample_freq.uhz);
572 	return 0;
573 }
574 
575 static int bma400_get_accel_oversampling_ratio(struct bma400_data *data)
576 {
577 	unsigned int val;
578 	unsigned int osr;
579 	int ret;
580 
581 	/*
582 	 * The oversampling ratio is stored in a different register
583 	 * based on the power-mode. In normal mode the OSR is stored
584 	 * in ACC_CONFIG1. In low-power mode it is stored in
585 	 * ACC_CONFIG0.
586 	 */
587 	switch (data->power_mode) {
588 	case POWER_MODE_LOW:
589 		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG, &val);
590 		if (ret) {
591 			data->oversampling_ratio = -1;
592 			return ret;
593 		}
594 
595 		osr = (val & BMA400_LP_OSR_MASK) >> BMA400_LP_OSR_SHIFT;
596 
597 		data->oversampling_ratio = osr;
598 		return 0;
599 	case POWER_MODE_NORMAL:
600 		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
601 		if (ret) {
602 			data->oversampling_ratio = -1;
603 			return ret;
604 		}
605 
606 		osr = (val & BMA400_NP_OSR_MASK) >> BMA400_NP_OSR_SHIFT;
607 
608 		data->oversampling_ratio = osr;
609 		return 0;
610 	case POWER_MODE_SLEEP:
611 		data->oversampling_ratio = 0;
612 		return 0;
613 	default:
614 		data->oversampling_ratio = -1;
615 		return -EINVAL;
616 	}
617 }
618 
619 static int bma400_set_accel_oversampling_ratio(struct bma400_data *data,
620 					       int val)
621 {
622 	unsigned int acc_config;
623 	int ret;
624 
625 	if (val & ~BMA400_TWO_BITS_MASK)
626 		return -EINVAL;
627 
628 	/*
629 	 * The oversampling ratio is stored in a different register
630 	 * based on the power-mode.
631 	 */
632 	switch (data->power_mode) {
633 	case POWER_MODE_LOW:
634 		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG,
635 				  &acc_config);
636 		if (ret)
637 			return ret;
638 
639 		ret = regmap_write(data->regmap, BMA400_ACC_CONFIG0_REG,
640 				   (acc_config & ~BMA400_LP_OSR_MASK) |
641 				   (val << BMA400_LP_OSR_SHIFT));
642 		if (ret) {
643 			dev_err(data->dev, "Failed to write out OSR\n");
644 			return ret;
645 		}
646 
647 		data->oversampling_ratio = val;
648 		return 0;
649 	case POWER_MODE_NORMAL:
650 		ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG,
651 				  &acc_config);
652 		if (ret)
653 			return ret;
654 
655 		ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG,
656 				   (acc_config & ~BMA400_NP_OSR_MASK) |
657 				   (val << BMA400_NP_OSR_SHIFT));
658 		if (ret) {
659 			dev_err(data->dev, "Failed to write out OSR\n");
660 			return ret;
661 		}
662 
663 		data->oversampling_ratio = val;
664 		return 0;
665 	default:
666 		return -EINVAL;
667 	}
668 	return ret;
669 }
670 
671 static int bma400_accel_scale_to_raw(struct bma400_data *data,
672 				     unsigned int val)
673 {
674 	int raw;
675 
676 	if (val == 0)
677 		return -EINVAL;
678 
679 	/* Note this works because BMA400_SCALE_MIN is odd */
680 	raw = __ffs(val);
681 
682 	if (val >> raw != BMA400_SCALE_MIN)
683 		return -EINVAL;
684 
685 	return raw;
686 }
687 
688 static int bma400_get_accel_scale(struct bma400_data *data)
689 {
690 	unsigned int raw_scale;
691 	unsigned int val;
692 	int ret;
693 
694 	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &val);
695 	if (ret)
696 		return ret;
697 
698 	raw_scale = (val & BMA400_ACC_SCALE_MASK) >> BMA400_SCALE_SHIFT;
699 	if (raw_scale > BMA400_TWO_BITS_MASK)
700 		return -EINVAL;
701 
702 	data->scale = BMA400_SCALE_MIN << raw_scale;
703 
704 	return 0;
705 }
706 
707 static int bma400_set_accel_scale(struct bma400_data *data, unsigned int val)
708 {
709 	unsigned int acc_config;
710 	int raw;
711 	int ret;
712 
713 	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG1_REG, &acc_config);
714 	if (ret)
715 		return ret;
716 
717 	raw = bma400_accel_scale_to_raw(data, val);
718 	if (raw < 0)
719 		return raw;
720 
721 	ret = regmap_write(data->regmap, BMA400_ACC_CONFIG1_REG,
722 			   (acc_config & ~BMA400_ACC_SCALE_MASK) |
723 			   (raw << BMA400_SCALE_SHIFT));
724 	if (ret)
725 		return ret;
726 
727 	data->scale = val;
728 	return 0;
729 }
730 
731 static int bma400_get_power_mode(struct bma400_data *data)
732 {
733 	unsigned int val;
734 	int ret;
735 
736 	ret = regmap_read(data->regmap, BMA400_STATUS_REG, &val);
737 	if (ret) {
738 		dev_err(data->dev, "Failed to read status register\n");
739 		return ret;
740 	}
741 
742 	data->power_mode = (val >> 1) & BMA400_TWO_BITS_MASK;
743 	return 0;
744 }
745 
746 static int bma400_set_power_mode(struct bma400_data *data,
747 				 enum bma400_power_mode mode)
748 {
749 	unsigned int val;
750 	int ret;
751 
752 	ret = regmap_read(data->regmap, BMA400_ACC_CONFIG0_REG, &val);
753 	if (ret)
754 		return ret;
755 
756 	if (data->power_mode == mode)
757 		return 0;
758 
759 	if (mode == POWER_MODE_INVALID)
760 		return -EINVAL;
761 
762 	/* Preserve the low-power oversample ratio etc */
763 	ret = regmap_write(data->regmap, BMA400_ACC_CONFIG0_REG,
764 			   mode | (val & ~BMA400_TWO_BITS_MASK));
765 	if (ret) {
766 		dev_err(data->dev, "Failed to write to power-mode\n");
767 		return ret;
768 	}
769 
770 	data->power_mode = mode;
771 
772 	/*
773 	 * Update our cached osr and odr based on the new
774 	 * power-mode.
775 	 */
776 	bma400_get_accel_output_data_rate(data);
777 	bma400_get_accel_oversampling_ratio(data);
778 	return 0;
779 }
780 
781 static int bma400_enable_steps(struct bma400_data *data, int val)
782 {
783 	int ret;
784 
785 	if (data->steps_enabled == val)
786 		return 0;
787 
788 	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG1_REG,
789 				 BMA400_STEP_INT_MSK,
790 				 FIELD_PREP(BMA400_STEP_INT_MSK, val ? 1 : 0));
791 	if (ret)
792 		return ret;
793 	data->steps_enabled = val;
794 	return ret;
795 }
796 
797 static int bma400_get_steps_reg(struct bma400_data *data, int *val)
798 {
799 	int ret;
800 
801 	u8 *steps_raw __free(kfree) = kmalloc(BMA400_STEP_RAW_LEN, GFP_KERNEL);
802 	if (!steps_raw)
803 		return -ENOMEM;
804 
805 	ret = regmap_bulk_read(data->regmap, BMA400_STEP_CNT0_REG,
806 			       steps_raw, BMA400_STEP_RAW_LEN);
807 	if (ret)
808 		return ret;
809 
810 	*val = get_unaligned_le24(steps_raw);
811 
812 	return IIO_VAL_INT;
813 }
814 
815 static void bma400_init_tables(void)
816 {
817 	int raw;
818 	int i;
819 
820 	for (i = 0; i + 1 < ARRAY_SIZE(bma400_sample_freqs); i += 2) {
821 		raw = (i / 2) + 5;
822 		bma400_output_data_rate_from_raw(raw, &bma400_sample_freqs[i],
823 						 &bma400_sample_freqs[i + 1]);
824 	}
825 
826 	for (i = 0; i + 1 < ARRAY_SIZE(bma400_scales); i += 2) {
827 		raw = i / 2;
828 		bma400_scales[i] = 0;
829 		bma400_scales[i + 1] = BMA400_SCALE_MIN << raw;
830 	}
831 }
832 
833 static void bma400_power_disable(void *data_ptr)
834 {
835 	struct bma400_data *data = data_ptr;
836 	int ret;
837 
838 	mutex_lock(&data->mutex);
839 	ret = bma400_set_power_mode(data, POWER_MODE_SLEEP);
840 	mutex_unlock(&data->mutex);
841 	if (ret)
842 		dev_warn(data->dev, "Failed to put device into sleep mode (%pe)\n",
843 			 ERR_PTR(ret));
844 }
845 
846 static enum iio_modifier bma400_act_to_mod(enum bma400_activity activity)
847 {
848 	switch (activity) {
849 	case BMA400_STILL:
850 		return IIO_MOD_STILL;
851 	case BMA400_WALKING:
852 		return IIO_MOD_WALKING;
853 	case BMA400_RUNNING:
854 		return IIO_MOD_RUNNING;
855 	default:
856 		return IIO_NO_MOD;
857 	}
858 }
859 
860 static int bma400_init(struct bma400_data *data)
861 {
862 	static const char * const regulator_names[] = { "vdd", "vddio" };
863 	unsigned int val;
864 	int ret;
865 
866 	ret = devm_regulator_bulk_get_enable(data->dev,
867 					     ARRAY_SIZE(regulator_names),
868 					     regulator_names);
869 	if (ret)
870 		return dev_err_probe(data->dev, ret, "Failed to get regulators\n");
871 
872 	/* Try to read chip_id register. It must return 0x90. */
873 	ret = regmap_read(data->regmap, BMA400_CHIP_ID_REG, &val);
874 	if (ret) {
875 		dev_err(data->dev, "Failed to read chip id register\n");
876 		return ret;
877 	}
878 
879 	if (val != BMA400_ID_REG_VAL) {
880 		dev_err(data->dev, "Chip ID mismatch\n");
881 		return -ENODEV;
882 	}
883 
884 	ret = bma400_get_power_mode(data);
885 	if (ret) {
886 		dev_err(data->dev, "Failed to get the initial power-mode\n");
887 		return ret;
888 	}
889 
890 	if (data->power_mode != POWER_MODE_NORMAL) {
891 		ret = bma400_set_power_mode(data, POWER_MODE_NORMAL);
892 		if (ret) {
893 			dev_err(data->dev, "Failed to wake up the device\n");
894 			return ret;
895 		}
896 		/*
897 		 * TODO: The datasheet waits 1500us here in the example, but
898 		 * lists 2/ODR as the wakeup time.
899 		 */
900 		usleep_range(1500, 2000);
901 	}
902 
903 	ret = devm_add_action_or_reset(data->dev, bma400_power_disable, data);
904 	if (ret)
905 		return ret;
906 
907 	bma400_init_tables();
908 
909 	ret = bma400_get_accel_output_data_rate(data);
910 	if (ret)
911 		return ret;
912 
913 	ret = bma400_get_accel_oversampling_ratio(data);
914 	if (ret)
915 		return ret;
916 
917 	ret = bma400_get_accel_scale(data);
918 	if (ret)
919 		return ret;
920 
921 	/* Configure INT1 pin to open drain */
922 	ret = regmap_write(data->regmap, BMA400_INT_IO_CTRL_REG, 0x06);
923 	if (ret)
924 		return ret;
925 	/*
926 	 * Once the interrupt engine is supported we might use the
927 	 * data_src_reg, but for now ensure this is set to the
928 	 * variable ODR filter selectable by the sample frequency
929 	 * channel.
930 	 */
931 	return regmap_write(data->regmap, BMA400_ACC_CONFIG2_REG, 0x00);
932 }
933 
934 static int bma400_read_raw(struct iio_dev *indio_dev,
935 			   struct iio_chan_spec const *chan, int *val,
936 			   int *val2, long mask)
937 {
938 	struct bma400_data *data = iio_priv(indio_dev);
939 	unsigned int activity;
940 	int ret;
941 
942 	switch (mask) {
943 	case IIO_CHAN_INFO_PROCESSED:
944 		switch (chan->type) {
945 		case IIO_TEMP:
946 			mutex_lock(&data->mutex);
947 			ret = bma400_get_temp_reg(data, val, val2);
948 			mutex_unlock(&data->mutex);
949 			return ret;
950 		case IIO_STEPS:
951 			return bma400_get_steps_reg(data, val);
952 		case IIO_ACTIVITY:
953 			ret = regmap_read(data->regmap, BMA400_STEP_STAT_REG,
954 					  &activity);
955 			if (ret)
956 				return ret;
957 			/*
958 			 * The device does not support confidence value levels,
959 			 * so we will always have 100% for current activity and
960 			 * 0% for the others.
961 			 */
962 			if (chan->channel2 == bma400_act_to_mod(activity))
963 				*val = 100;
964 			else
965 				*val = 0;
966 			return IIO_VAL_INT;
967 		default:
968 			return -EINVAL;
969 		}
970 	case IIO_CHAN_INFO_RAW:
971 		mutex_lock(&data->mutex);
972 		ret = bma400_get_accel_reg(data, chan, val);
973 		mutex_unlock(&data->mutex);
974 		return ret;
975 	case IIO_CHAN_INFO_SAMP_FREQ:
976 		switch (chan->type) {
977 		case IIO_ACCEL:
978 			if (data->sample_freq.hz < 0)
979 				return -EINVAL;
980 
981 			*val = data->sample_freq.hz;
982 			*val2 = data->sample_freq.uhz;
983 			return IIO_VAL_INT_PLUS_MICRO;
984 		case IIO_TEMP:
985 			/*
986 			 * Runs at a fixed sampling frequency. See Section 4.4
987 			 * of the datasheet.
988 			 */
989 			*val = 6;
990 			*val2 = 250000;
991 			return IIO_VAL_INT_PLUS_MICRO;
992 		default:
993 			return -EINVAL;
994 		}
995 	case IIO_CHAN_INFO_SCALE:
996 		*val = 0;
997 		*val2 = data->scale;
998 		return IIO_VAL_INT_PLUS_MICRO;
999 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1000 		/*
1001 		 * TODO: We could avoid this logic and returning -EINVAL here if
1002 		 * we set both the low-power and normal mode OSR registers when
1003 		 * we configure the device.
1004 		 */
1005 		if (data->oversampling_ratio < 0)
1006 			return -EINVAL;
1007 
1008 		*val = data->oversampling_ratio;
1009 		return IIO_VAL_INT;
1010 	case IIO_CHAN_INFO_ENABLE:
1011 		*val = data->steps_enabled;
1012 		return IIO_VAL_INT;
1013 	default:
1014 		return -EINVAL;
1015 	}
1016 }
1017 
1018 static int bma400_read_avail(struct iio_dev *indio_dev,
1019 			     struct iio_chan_spec const *chan,
1020 			     const int **vals, int *type, int *length,
1021 			     long mask)
1022 {
1023 	switch (mask) {
1024 	case IIO_CHAN_INFO_SCALE:
1025 		*type = IIO_VAL_INT_PLUS_MICRO;
1026 		*vals = bma400_scales;
1027 		*length = ARRAY_SIZE(bma400_scales);
1028 		return IIO_AVAIL_LIST;
1029 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1030 		*type = IIO_VAL_INT;
1031 		*vals = bma400_osr_range;
1032 		*length = ARRAY_SIZE(bma400_osr_range);
1033 		return IIO_AVAIL_RANGE;
1034 	case IIO_CHAN_INFO_SAMP_FREQ:
1035 		*type = IIO_VAL_INT_PLUS_MICRO;
1036 		*vals = bma400_sample_freqs;
1037 		*length = ARRAY_SIZE(bma400_sample_freqs);
1038 		return IIO_AVAIL_LIST;
1039 	default:
1040 		return -EINVAL;
1041 	}
1042 }
1043 
1044 static int bma400_write_raw(struct iio_dev *indio_dev,
1045 			    struct iio_chan_spec const *chan, int val, int val2,
1046 			    long mask)
1047 {
1048 	struct bma400_data *data = iio_priv(indio_dev);
1049 	int ret;
1050 
1051 	switch (mask) {
1052 	case IIO_CHAN_INFO_SAMP_FREQ:
1053 		/*
1054 		 * The sample frequency is readonly for the temperature
1055 		 * register and a fixed value in low-power mode.
1056 		 */
1057 		if (chan->type != IIO_ACCEL)
1058 			return -EINVAL;
1059 
1060 		mutex_lock(&data->mutex);
1061 		ret = bma400_set_accel_output_data_rate(data, val, val2);
1062 		mutex_unlock(&data->mutex);
1063 		return ret;
1064 	case IIO_CHAN_INFO_SCALE:
1065 		if (val != 0 ||
1066 		    val2 < BMA400_SCALE_MIN || val2 > BMA400_SCALE_MAX)
1067 			return -EINVAL;
1068 
1069 		mutex_lock(&data->mutex);
1070 		ret = bma400_set_accel_scale(data, val2);
1071 		mutex_unlock(&data->mutex);
1072 		return ret;
1073 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1074 		mutex_lock(&data->mutex);
1075 		ret = bma400_set_accel_oversampling_ratio(data, val);
1076 		mutex_unlock(&data->mutex);
1077 		return ret;
1078 	case IIO_CHAN_INFO_ENABLE:
1079 		mutex_lock(&data->mutex);
1080 		ret = bma400_enable_steps(data, val);
1081 		mutex_unlock(&data->mutex);
1082 		return ret;
1083 	default:
1084 		return -EINVAL;
1085 	}
1086 }
1087 
1088 static int bma400_write_raw_get_fmt(struct iio_dev *indio_dev,
1089 				    struct iio_chan_spec const *chan,
1090 				    long mask)
1091 {
1092 	switch (mask) {
1093 	case IIO_CHAN_INFO_SAMP_FREQ:
1094 		return IIO_VAL_INT_PLUS_MICRO;
1095 	case IIO_CHAN_INFO_SCALE:
1096 		return IIO_VAL_INT_PLUS_MICRO;
1097 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
1098 		return IIO_VAL_INT;
1099 	case IIO_CHAN_INFO_ENABLE:
1100 		return IIO_VAL_INT;
1101 	default:
1102 		return -EINVAL;
1103 	}
1104 }
1105 
1106 static int bma400_read_event_config(struct iio_dev *indio_dev,
1107 				    const struct iio_chan_spec *chan,
1108 				    enum iio_event_type type,
1109 				    enum iio_event_direction dir)
1110 {
1111 	struct bma400_data *data = iio_priv(indio_dev);
1112 
1113 	switch (chan->type) {
1114 	case IIO_ACCEL:
1115 		switch (dir) {
1116 		case IIO_EV_DIR_RISING:
1117 			return FIELD_GET(BMA400_INT_GEN1_MSK,
1118 					 data->generic_event_en);
1119 		case IIO_EV_DIR_FALLING:
1120 			return FIELD_GET(BMA400_INT_GEN2_MSK,
1121 					 data->generic_event_en);
1122 		case IIO_EV_DIR_SINGLETAP:
1123 			return FIELD_GET(BMA400_S_TAP_MSK,
1124 					 data->tap_event_en_bitmask);
1125 		case IIO_EV_DIR_DOUBLETAP:
1126 			return FIELD_GET(BMA400_D_TAP_MSK,
1127 					 data->tap_event_en_bitmask);
1128 		default:
1129 			return -EINVAL;
1130 		}
1131 	case IIO_STEPS:
1132 		return data->step_event_en;
1133 	case IIO_ACTIVITY:
1134 		return data->activity_event_en;
1135 	default:
1136 		return -EINVAL;
1137 	}
1138 }
1139 
1140 static int bma400_steps_event_enable(struct bma400_data *data, int state)
1141 {
1142 	int ret;
1143 
1144 	ret = bma400_enable_steps(data, 1);
1145 	if (ret)
1146 		return ret;
1147 
1148 	ret = regmap_update_bits(data->regmap, BMA400_INT12_MAP_REG,
1149 				 BMA400_STEP_INT_MSK,
1150 				 FIELD_PREP(BMA400_STEP_INT_MSK,
1151 					    state));
1152 	if (ret)
1153 		return ret;
1154 	data->step_event_en = state;
1155 	return 0;
1156 }
1157 
1158 static int bma400_activity_event_en(struct bma400_data *data,
1159 				    enum iio_event_direction dir,
1160 				    int state)
1161 {
1162 	int ret, reg, msk, value;
1163 	int field_value = 0;
1164 
1165 	switch (dir) {
1166 	case IIO_EV_DIR_RISING:
1167 		reg = BMA400_GEN1INT_CONFIG0;
1168 		msk = BMA400_INT_GEN1_MSK;
1169 		value = 2;
1170 		set_mask_bits(&field_value, BMA400_INT_GEN1_MSK,
1171 			      FIELD_PREP(BMA400_INT_GEN1_MSK, state));
1172 		break;
1173 	case IIO_EV_DIR_FALLING:
1174 		reg = BMA400_GEN2INT_CONFIG0;
1175 		msk = BMA400_INT_GEN2_MSK;
1176 		value = 0;
1177 		set_mask_bits(&field_value, BMA400_INT_GEN2_MSK,
1178 			      FIELD_PREP(BMA400_INT_GEN2_MSK, state));
1179 		break;
1180 	default:
1181 		return -EINVAL;
1182 	}
1183 
1184 	/* Enabling all axis for interrupt evaluation */
1185 	ret = regmap_write(data->regmap, reg, 0xF8);
1186 	if (ret)
1187 		return ret;
1188 
1189 	/* OR combination of all axis for interrupt evaluation */
1190 	ret = regmap_write(data->regmap, reg + BMA400_GEN_CONFIG1_OFF, value);
1191 	if (ret)
1192 		return ret;
1193 
1194 	/* Initial value to avoid interrupts while enabling*/
1195 	ret = regmap_write(data->regmap, reg + BMA400_GEN_CONFIG2_OFF, 0x0A);
1196 	if (ret)
1197 		return ret;
1198 
1199 	/* Initial duration value to avoid interrupts while enabling*/
1200 	ret = regmap_write(data->regmap, reg + BMA400_GEN_CONFIG31_OFF, 0x0F);
1201 	if (ret)
1202 		return ret;
1203 
1204 	ret = regmap_update_bits(data->regmap, BMA400_INT1_MAP_REG, msk,
1205 				 field_value);
1206 	if (ret)
1207 		return ret;
1208 
1209 	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG0_REG, msk,
1210 				 field_value);
1211 	if (ret)
1212 		return ret;
1213 
1214 	set_mask_bits(&data->generic_event_en, msk, field_value);
1215 	return 0;
1216 }
1217 
1218 static int bma400_tap_event_en(struct bma400_data *data,
1219 			       enum iio_event_direction dir, int state)
1220 {
1221 	unsigned int mask, field_value;
1222 	int ret;
1223 
1224 	/*
1225 	 * Tap interrupts can be configured only in normal mode.
1226 	 * See table in section 4.3 "Power modes - performance modes" of
1227 	 * datasheet v1.2.
1228 	 */
1229 	if (data->power_mode != POWER_MODE_NORMAL)
1230 		return -EINVAL;
1231 
1232 	/*
1233 	 * Tap interrupts are operating with a data rate of 200Hz.
1234 	 * See section 4.7 "Tap sensing interrupt" in datasheet v1.2.
1235 	 */
1236 	if (data->sample_freq.hz != 200 && state) {
1237 		dev_err(data->dev, "Invalid data rate for tap interrupts.\n");
1238 		return -EINVAL;
1239 	}
1240 
1241 	ret = regmap_update_bits(data->regmap, BMA400_INT12_MAP_REG,
1242 				 BMA400_S_TAP_MSK,
1243 				 FIELD_PREP(BMA400_S_TAP_MSK, state));
1244 	if (ret)
1245 		return ret;
1246 
1247 	switch (dir) {
1248 	case IIO_EV_DIR_SINGLETAP:
1249 		mask = BMA400_S_TAP_MSK;
1250 		set_mask_bits(&field_value, BMA400_S_TAP_MSK,
1251 			      FIELD_PREP(BMA400_S_TAP_MSK, state));
1252 		break;
1253 	case IIO_EV_DIR_DOUBLETAP:
1254 		mask = BMA400_D_TAP_MSK;
1255 		set_mask_bits(&field_value, BMA400_D_TAP_MSK,
1256 			      FIELD_PREP(BMA400_D_TAP_MSK, state));
1257 		break;
1258 	default:
1259 		return -EINVAL;
1260 	}
1261 
1262 	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG1_REG, mask,
1263 				 field_value);
1264 	if (ret)
1265 		return ret;
1266 
1267 	set_mask_bits(&data->tap_event_en_bitmask, mask, field_value);
1268 
1269 	return 0;
1270 }
1271 
1272 static int bma400_disable_adv_interrupt(struct bma400_data *data)
1273 {
1274 	int ret;
1275 
1276 	ret = regmap_write(data->regmap, BMA400_INT_CONFIG0_REG, 0);
1277 	if (ret)
1278 		return ret;
1279 
1280 	ret = regmap_write(data->regmap, BMA400_INT_CONFIG1_REG, 0);
1281 	if (ret)
1282 		return ret;
1283 
1284 	data->tap_event_en_bitmask = 0;
1285 	data->generic_event_en = 0;
1286 	data->step_event_en = false;
1287 	data->activity_event_en = false;
1288 
1289 	return 0;
1290 }
1291 
1292 static int bma400_write_event_config(struct iio_dev *indio_dev,
1293 				     const struct iio_chan_spec *chan,
1294 				     enum iio_event_type type,
1295 				     enum iio_event_direction dir, int state)
1296 {
1297 	struct bma400_data *data = iio_priv(indio_dev);
1298 	int ret;
1299 
1300 	switch (chan->type) {
1301 	case IIO_ACCEL:
1302 		switch (type) {
1303 		case IIO_EV_TYPE_MAG:
1304 			mutex_lock(&data->mutex);
1305 			ret = bma400_activity_event_en(data, dir, state);
1306 			mutex_unlock(&data->mutex);
1307 			return ret;
1308 		case IIO_EV_TYPE_GESTURE:
1309 			mutex_lock(&data->mutex);
1310 			ret = bma400_tap_event_en(data, dir, state);
1311 			mutex_unlock(&data->mutex);
1312 			return ret;
1313 		default:
1314 			return -EINVAL;
1315 		}
1316 	case IIO_STEPS:
1317 		mutex_lock(&data->mutex);
1318 		ret = bma400_steps_event_enable(data, state);
1319 		mutex_unlock(&data->mutex);
1320 		return ret;
1321 	case IIO_ACTIVITY:
1322 		mutex_lock(&data->mutex);
1323 		if (!data->step_event_en) {
1324 			ret = bma400_steps_event_enable(data, true);
1325 			if (ret) {
1326 				mutex_unlock(&data->mutex);
1327 				return ret;
1328 			}
1329 		}
1330 		data->activity_event_en = state;
1331 		mutex_unlock(&data->mutex);
1332 		return 0;
1333 	default:
1334 		return -EINVAL;
1335 	}
1336 }
1337 
1338 static int get_gen_config_reg(enum iio_event_direction dir)
1339 {
1340 	switch (dir) {
1341 	case IIO_EV_DIR_FALLING:
1342 		return BMA400_GEN2INT_CONFIG0;
1343 	case IIO_EV_DIR_RISING:
1344 		return BMA400_GEN1INT_CONFIG0;
1345 	default:
1346 		return -EINVAL;
1347 	}
1348 }
1349 
1350 static int bma400_read_event_value(struct iio_dev *indio_dev,
1351 				   const struct iio_chan_spec *chan,
1352 				   enum iio_event_type type,
1353 				   enum iio_event_direction dir,
1354 				   enum iio_event_info info,
1355 				   int *val, int *val2)
1356 {
1357 	struct bma400_data *data = iio_priv(indio_dev);
1358 	int ret, reg, reg_val, raw;
1359 
1360 	if (chan->type != IIO_ACCEL)
1361 		return -EINVAL;
1362 
1363 	switch (type) {
1364 	case IIO_EV_TYPE_MAG:
1365 		reg = get_gen_config_reg(dir);
1366 		if (reg < 0)
1367 			return -EINVAL;
1368 
1369 		*val2 = 0;
1370 		switch (info) {
1371 		case IIO_EV_INFO_VALUE:
1372 			ret = regmap_read(data->regmap,
1373 					  reg + BMA400_GEN_CONFIG2_OFF,
1374 					  val);
1375 			if (ret)
1376 				return ret;
1377 			return IIO_VAL_INT;
1378 		case IIO_EV_INFO_PERIOD:
1379 			mutex_lock(&data->mutex);
1380 			ret = regmap_bulk_read(data->regmap,
1381 					       reg + BMA400_GEN_CONFIG3_OFF,
1382 					       &data->duration,
1383 					       sizeof(data->duration));
1384 			if (ret) {
1385 				mutex_unlock(&data->mutex);
1386 				return ret;
1387 			}
1388 			*val = be16_to_cpu(data->duration);
1389 			mutex_unlock(&data->mutex);
1390 			return IIO_VAL_INT;
1391 		case IIO_EV_INFO_HYSTERESIS:
1392 			ret = regmap_read(data->regmap, reg, val);
1393 			if (ret)
1394 				return ret;
1395 			*val = FIELD_GET(BMA400_GEN_HYST_MSK, *val);
1396 			return IIO_VAL_INT;
1397 		default:
1398 			return -EINVAL;
1399 		}
1400 	case IIO_EV_TYPE_GESTURE:
1401 		switch (info) {
1402 		case IIO_EV_INFO_VALUE:
1403 			ret = regmap_read(data->regmap, BMA400_TAP_CONFIG,
1404 					  &reg_val);
1405 			if (ret)
1406 				return ret;
1407 
1408 			*val = FIELD_GET(BMA400_TAP_SEN_MSK, reg_val);
1409 			return IIO_VAL_INT;
1410 		case IIO_EV_INFO_RESET_TIMEOUT:
1411 			ret = regmap_read(data->regmap, BMA400_TAP_CONFIG1,
1412 					  &reg_val);
1413 			if (ret)
1414 				return ret;
1415 
1416 			raw = FIELD_GET(BMA400_TAP_QUIET_MSK, reg_val);
1417 			*val = 0;
1418 			*val2 = tap_reset_timeout[raw];
1419 			return IIO_VAL_INT_PLUS_MICRO;
1420 		case IIO_EV_INFO_TAP2_MIN_DELAY:
1421 			ret = regmap_read(data->regmap, BMA400_TAP_CONFIG1,
1422 					  &reg_val);
1423 			if (ret)
1424 				return ret;
1425 
1426 			raw = FIELD_GET(BMA400_TAP_QUIETDT_MSK, reg_val);
1427 			*val = 0;
1428 			*val2 = double_tap2_min_delay[raw];
1429 			return IIO_VAL_INT_PLUS_MICRO;
1430 		default:
1431 			return -EINVAL;
1432 		}
1433 	default:
1434 		return -EINVAL;
1435 	}
1436 }
1437 
1438 static int bma400_write_event_value(struct iio_dev *indio_dev,
1439 				    const struct iio_chan_spec *chan,
1440 				    enum iio_event_type type,
1441 				    enum iio_event_direction dir,
1442 				    enum iio_event_info info,
1443 				    int val, int val2)
1444 {
1445 	struct bma400_data *data = iio_priv(indio_dev);
1446 	int reg, ret, raw;
1447 
1448 	if (chan->type != IIO_ACCEL)
1449 		return -EINVAL;
1450 
1451 	switch (type) {
1452 	case IIO_EV_TYPE_MAG:
1453 		reg = get_gen_config_reg(dir);
1454 		if (reg < 0)
1455 			return -EINVAL;
1456 
1457 		switch (info) {
1458 		case IIO_EV_INFO_VALUE:
1459 			if (val < 1 || val > 255)
1460 				return -EINVAL;
1461 
1462 			return regmap_write(data->regmap,
1463 					    reg + BMA400_GEN_CONFIG2_OFF,
1464 					    val);
1465 		case IIO_EV_INFO_PERIOD:
1466 			if (val < 1 || val > 65535)
1467 				return -EINVAL;
1468 
1469 			mutex_lock(&data->mutex);
1470 			put_unaligned_be16(val, &data->duration);
1471 			ret = regmap_bulk_write(data->regmap,
1472 						reg + BMA400_GEN_CONFIG3_OFF,
1473 						&data->duration,
1474 						sizeof(data->duration));
1475 			mutex_unlock(&data->mutex);
1476 			return ret;
1477 		case IIO_EV_INFO_HYSTERESIS:
1478 			if (val < 0 || val > 3)
1479 				return -EINVAL;
1480 
1481 			return regmap_update_bits(data->regmap, reg,
1482 						  BMA400_GEN_HYST_MSK,
1483 						  FIELD_PREP(BMA400_GEN_HYST_MSK,
1484 							     val));
1485 		default:
1486 			return -EINVAL;
1487 		}
1488 	case IIO_EV_TYPE_GESTURE:
1489 		switch (info) {
1490 		case IIO_EV_INFO_VALUE:
1491 			if (val < 0 || val > 7)
1492 				return -EINVAL;
1493 
1494 			return regmap_update_bits(data->regmap,
1495 						  BMA400_TAP_CONFIG,
1496 						  BMA400_TAP_SEN_MSK,
1497 						  FIELD_PREP(BMA400_TAP_SEN_MSK,
1498 							     val));
1499 		case IIO_EV_INFO_RESET_TIMEOUT:
1500 			raw = usec_to_tapreg_raw(val2, tap_reset_timeout);
1501 			if (raw < 0)
1502 				return -EINVAL;
1503 
1504 			return regmap_update_bits(data->regmap,
1505 						  BMA400_TAP_CONFIG1,
1506 						  BMA400_TAP_QUIET_MSK,
1507 						  FIELD_PREP(BMA400_TAP_QUIET_MSK,
1508 							     raw));
1509 		case IIO_EV_INFO_TAP2_MIN_DELAY:
1510 			raw = usec_to_tapreg_raw(val2, double_tap2_min_delay);
1511 			if (raw < 0)
1512 				return -EINVAL;
1513 
1514 			return regmap_update_bits(data->regmap,
1515 						  BMA400_TAP_CONFIG1,
1516 						  BMA400_TAP_QUIETDT_MSK,
1517 						  FIELD_PREP(BMA400_TAP_QUIETDT_MSK,
1518 							     raw));
1519 		default:
1520 			return -EINVAL;
1521 		}
1522 	default:
1523 		return -EINVAL;
1524 	}
1525 }
1526 
1527 static int bma400_data_rdy_trigger_set_state(struct iio_trigger *trig,
1528 					     bool state)
1529 {
1530 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
1531 	struct bma400_data *data = iio_priv(indio_dev);
1532 	int ret;
1533 
1534 	ret = regmap_update_bits(data->regmap, BMA400_INT_CONFIG0_REG,
1535 				 BMA400_INT_DRDY_MSK,
1536 				 FIELD_PREP(BMA400_INT_DRDY_MSK, state));
1537 	if (ret)
1538 		return ret;
1539 
1540 	return regmap_update_bits(data->regmap, BMA400_INT1_MAP_REG,
1541 				  BMA400_INT_DRDY_MSK,
1542 				  FIELD_PREP(BMA400_INT_DRDY_MSK, state));
1543 }
1544 
1545 static const unsigned long bma400_avail_scan_masks[] = {
1546 	BIT(BMA400_ACCL_X) | BIT(BMA400_ACCL_Y) | BIT(BMA400_ACCL_Z),
1547 	BIT(BMA400_ACCL_X) | BIT(BMA400_ACCL_Y) | BIT(BMA400_ACCL_Z)
1548 	| BIT(BMA400_TEMP),
1549 	0
1550 };
1551 
1552 static const struct iio_info bma400_info = {
1553 	.read_raw          = bma400_read_raw,
1554 	.read_avail        = bma400_read_avail,
1555 	.write_raw         = bma400_write_raw,
1556 	.write_raw_get_fmt = bma400_write_raw_get_fmt,
1557 	.read_event_config = bma400_read_event_config,
1558 	.write_event_config = bma400_write_event_config,
1559 	.write_event_value = bma400_write_event_value,
1560 	.read_event_value = bma400_read_event_value,
1561 	.event_attrs = &bma400_event_attribute_group,
1562 };
1563 
1564 static const struct iio_trigger_ops bma400_trigger_ops = {
1565 	.set_trigger_state = &bma400_data_rdy_trigger_set_state,
1566 	.validate_device = &iio_trigger_validate_own_device,
1567 };
1568 
1569 static irqreturn_t bma400_trigger_handler(int irq, void *p)
1570 {
1571 	struct iio_poll_func *pf = p;
1572 	struct iio_dev *indio_dev = pf->indio_dev;
1573 	struct bma400_data *data = iio_priv(indio_dev);
1574 	int ret, temp;
1575 
1576 	/* Lock to protect the data->buffer */
1577 	mutex_lock(&data->mutex);
1578 
1579 	/* bulk read six registers, with the base being the LSB register */
1580 	ret = regmap_bulk_read(data->regmap, BMA400_X_AXIS_LSB_REG,
1581 			       &data->buffer.buff, sizeof(data->buffer.buff));
1582 	if (ret)
1583 		goto unlock_err;
1584 
1585 	if (test_bit(BMA400_TEMP, indio_dev->active_scan_mask)) {
1586 		ret = regmap_read(data->regmap, BMA400_TEMP_DATA_REG, &temp);
1587 		if (ret)
1588 			goto unlock_err;
1589 
1590 		data->buffer.temperature = temp;
1591 	}
1592 
1593 	iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer,
1594 					   iio_get_time_ns(indio_dev));
1595 
1596 	mutex_unlock(&data->mutex);
1597 	iio_trigger_notify_done(indio_dev->trig);
1598 	return IRQ_HANDLED;
1599 
1600 unlock_err:
1601 	mutex_unlock(&data->mutex);
1602 	return IRQ_NONE;
1603 }
1604 
1605 static irqreturn_t bma400_interrupt(int irq, void *private)
1606 {
1607 	struct iio_dev *indio_dev = private;
1608 	struct bma400_data *data = iio_priv(indio_dev);
1609 	s64 timestamp = iio_get_time_ns(indio_dev);
1610 	unsigned int act, ev_dir = IIO_EV_DIR_NONE;
1611 	int ret;
1612 
1613 	/* Lock to protect the data->status */
1614 	mutex_lock(&data->mutex);
1615 	ret = regmap_bulk_read(data->regmap, BMA400_INT_STAT0_REG,
1616 			       &data->status,
1617 			       sizeof(data->status));
1618 	/*
1619 	 * if none of the bit is set in the status register then it is
1620 	 * spurious interrupt.
1621 	 */
1622 	if (ret || !data->status)
1623 		goto unlock_err;
1624 
1625 	/*
1626 	 * Disable all advance interrupts if interrupt engine overrun occurs.
1627 	 * See section 4.7 "Interrupt engine overrun" in datasheet v1.2.
1628 	 */
1629 	if (FIELD_GET(BMA400_INT_ENG_OVRUN_MSK, le16_to_cpu(data->status))) {
1630 		bma400_disable_adv_interrupt(data);
1631 		dev_err(data->dev, "Interrupt engine overrun\n");
1632 		goto unlock_err;
1633 	}
1634 
1635 	if (FIELD_GET(BMA400_INT_S_TAP_MSK, le16_to_cpu(data->status)))
1636 		iio_push_event(indio_dev,
1637 			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
1638 						  IIO_MOD_X_OR_Y_OR_Z,
1639 						  IIO_EV_TYPE_GESTURE,
1640 						  IIO_EV_DIR_SINGLETAP),
1641 			       timestamp);
1642 
1643 	if (FIELD_GET(BMA400_INT_D_TAP_MSK, le16_to_cpu(data->status)))
1644 		iio_push_event(indio_dev,
1645 			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
1646 						  IIO_MOD_X_OR_Y_OR_Z,
1647 						  IIO_EV_TYPE_GESTURE,
1648 						  IIO_EV_DIR_DOUBLETAP),
1649 			       timestamp);
1650 
1651 	if (FIELD_GET(BMA400_INT_GEN1_MSK, le16_to_cpu(data->status)))
1652 		ev_dir = IIO_EV_DIR_RISING;
1653 
1654 	if (FIELD_GET(BMA400_INT_GEN2_MSK, le16_to_cpu(data->status)))
1655 		ev_dir = IIO_EV_DIR_FALLING;
1656 
1657 	if (ev_dir != IIO_EV_DIR_NONE) {
1658 		iio_push_event(indio_dev,
1659 			       IIO_MOD_EVENT_CODE(IIO_ACCEL, 0,
1660 						  IIO_MOD_X_OR_Y_OR_Z,
1661 						  IIO_EV_TYPE_MAG, ev_dir),
1662 			       timestamp);
1663 	}
1664 
1665 	if (FIELD_GET(BMA400_STEP_STAT_MASK, le16_to_cpu(data->status))) {
1666 		iio_push_event(indio_dev,
1667 			       IIO_MOD_EVENT_CODE(IIO_STEPS, 0, IIO_NO_MOD,
1668 						  IIO_EV_TYPE_CHANGE,
1669 						  IIO_EV_DIR_NONE),
1670 			       timestamp);
1671 
1672 		if (data->activity_event_en) {
1673 			ret = regmap_read(data->regmap, BMA400_STEP_STAT_REG,
1674 					  &act);
1675 			if (ret)
1676 				goto unlock_err;
1677 
1678 			iio_push_event(indio_dev,
1679 				       IIO_MOD_EVENT_CODE(IIO_ACTIVITY, 0,
1680 							  bma400_act_to_mod(act),
1681 							  IIO_EV_TYPE_CHANGE,
1682 							  IIO_EV_DIR_NONE),
1683 				       timestamp);
1684 		}
1685 	}
1686 
1687 	if (FIELD_GET(BMA400_INT_DRDY_MSK, le16_to_cpu(data->status))) {
1688 		mutex_unlock(&data->mutex);
1689 		iio_trigger_poll_nested(data->trig);
1690 		return IRQ_HANDLED;
1691 	}
1692 
1693 	mutex_unlock(&data->mutex);
1694 	return IRQ_HANDLED;
1695 
1696 unlock_err:
1697 	mutex_unlock(&data->mutex);
1698 	return IRQ_NONE;
1699 }
1700 
1701 int bma400_probe(struct device *dev, struct regmap *regmap, int irq,
1702 		 const char *name)
1703 {
1704 	struct iio_dev *indio_dev;
1705 	struct bma400_data *data;
1706 	int ret;
1707 
1708 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
1709 	if (!indio_dev)
1710 		return -ENOMEM;
1711 
1712 	data = iio_priv(indio_dev);
1713 	data->regmap = regmap;
1714 	data->dev = dev;
1715 
1716 	ret = bma400_init(data);
1717 	if (ret)
1718 		return ret;
1719 
1720 	ret = iio_read_mount_matrix(dev, &data->orientation);
1721 	if (ret)
1722 		return ret;
1723 
1724 	mutex_init(&data->mutex);
1725 	indio_dev->name = name;
1726 	indio_dev->info = &bma400_info;
1727 	indio_dev->channels = bma400_channels;
1728 	indio_dev->num_channels = ARRAY_SIZE(bma400_channels);
1729 	indio_dev->available_scan_masks = bma400_avail_scan_masks;
1730 	indio_dev->modes = INDIO_DIRECT_MODE;
1731 
1732 	if (irq > 0) {
1733 		data->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
1734 						    indio_dev->name,
1735 						    iio_device_id(indio_dev));
1736 		if (!data->trig)
1737 			return -ENOMEM;
1738 
1739 		data->trig->ops = &bma400_trigger_ops;
1740 		iio_trigger_set_drvdata(data->trig, indio_dev);
1741 
1742 		ret = devm_iio_trigger_register(data->dev, data->trig);
1743 		if (ret)
1744 			return dev_err_probe(data->dev, ret,
1745 					     "iio trigger register fail\n");
1746 
1747 		indio_dev->trig = iio_trigger_get(data->trig);
1748 		ret = devm_request_threaded_irq(dev, irq, NULL,
1749 						&bma400_interrupt,
1750 						IRQF_TRIGGER_RISING | IRQF_ONESHOT,
1751 						indio_dev->name, indio_dev);
1752 		if (ret)
1753 			return dev_err_probe(data->dev, ret,
1754 					     "request irq %d failed\n", irq);
1755 	}
1756 
1757 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
1758 					      &bma400_trigger_handler, NULL);
1759 	if (ret)
1760 		return dev_err_probe(data->dev, ret,
1761 				     "iio triggered buffer setup failed\n");
1762 
1763 	return devm_iio_device_register(dev, indio_dev);
1764 }
1765 EXPORT_SYMBOL_NS(bma400_probe, IIO_BMA400);
1766 
1767 MODULE_AUTHOR("Dan Robertson <dan@dlrobertson.com>");
1768 MODULE_AUTHOR("Jagath Jog J <jagathjog1996@gmail.com>");
1769 MODULE_DESCRIPTION("Bosch BMA400 triaxial acceleration sensor core");
1770 MODULE_LICENSE("GPL");
1771