1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * BMI160 - Bosch IMU (accel, gyro plus external magnetometer)
4  *
5  * Copyright (c) 2016, Intel Corporation.
6  * Copyright (c) 2019, Martin Kelly.
7  *
8  * IIO core driver for BMI160, with support for I2C/SPI busses
9  *
10  * TODO: magnetometer, hardware FIFO
11  */
12 #include <linux/module.h>
13 #include <linux/regmap.h>
14 #include <linux/acpi.h>
15 #include <linux/delay.h>
16 #include <linux/irq.h>
17 #include <linux/of_irq.h>
18 
19 #include <linux/iio/iio.h>
20 #include <linux/iio/triggered_buffer.h>
21 #include <linux/iio/trigger_consumer.h>
22 #include <linux/iio/buffer.h>
23 #include <linux/iio/sysfs.h>
24 #include <linux/iio/trigger.h>
25 
26 #include "bmi160.h"
27 
28 #define BMI160_REG_CHIP_ID	0x00
29 #define BMI160_CHIP_ID_VAL	0xD1
30 
31 #define BMI160_REG_PMU_STATUS	0x03
32 
33 /* X axis data low byte address, the rest can be obtained using axis offset */
34 #define BMI160_REG_DATA_MAGN_XOUT_L	0x04
35 #define BMI160_REG_DATA_GYRO_XOUT_L	0x0C
36 #define BMI160_REG_DATA_ACCEL_XOUT_L	0x12
37 
38 #define BMI160_REG_ACCEL_CONFIG		0x40
39 #define BMI160_ACCEL_CONFIG_ODR_MASK	GENMASK(3, 0)
40 #define BMI160_ACCEL_CONFIG_BWP_MASK	GENMASK(6, 4)
41 
42 #define BMI160_REG_ACCEL_RANGE		0x41
43 #define BMI160_ACCEL_RANGE_2G		0x03
44 #define BMI160_ACCEL_RANGE_4G		0x05
45 #define BMI160_ACCEL_RANGE_8G		0x08
46 #define BMI160_ACCEL_RANGE_16G		0x0C
47 
48 #define BMI160_REG_GYRO_CONFIG		0x42
49 #define BMI160_GYRO_CONFIG_ODR_MASK	GENMASK(3, 0)
50 #define BMI160_GYRO_CONFIG_BWP_MASK	GENMASK(5, 4)
51 
52 #define BMI160_REG_GYRO_RANGE		0x43
53 #define BMI160_GYRO_RANGE_2000DPS	0x00
54 #define BMI160_GYRO_RANGE_1000DPS	0x01
55 #define BMI160_GYRO_RANGE_500DPS	0x02
56 #define BMI160_GYRO_RANGE_250DPS	0x03
57 #define BMI160_GYRO_RANGE_125DPS	0x04
58 
59 #define BMI160_REG_CMD			0x7E
60 #define BMI160_CMD_ACCEL_PM_SUSPEND	0x10
61 #define BMI160_CMD_ACCEL_PM_NORMAL	0x11
62 #define BMI160_CMD_ACCEL_PM_LOW_POWER	0x12
63 #define BMI160_CMD_GYRO_PM_SUSPEND	0x14
64 #define BMI160_CMD_GYRO_PM_NORMAL	0x15
65 #define BMI160_CMD_GYRO_PM_FAST_STARTUP	0x17
66 #define BMI160_CMD_SOFTRESET		0xB6
67 
68 #define BMI160_REG_INT_EN		0x51
69 #define BMI160_DRDY_INT_EN		BIT(4)
70 
71 #define BMI160_REG_INT_OUT_CTRL		0x53
72 #define BMI160_INT_OUT_CTRL_MASK	0x0f
73 #define BMI160_INT1_OUT_CTRL_SHIFT	0
74 #define BMI160_INT2_OUT_CTRL_SHIFT	4
75 #define BMI160_EDGE_TRIGGERED		BIT(0)
76 #define BMI160_ACTIVE_HIGH		BIT(1)
77 #define BMI160_OPEN_DRAIN		BIT(2)
78 #define BMI160_OUTPUT_EN		BIT(3)
79 
80 #define BMI160_REG_INT_LATCH		0x54
81 #define BMI160_INT1_LATCH_MASK		BIT(4)
82 #define BMI160_INT2_LATCH_MASK		BIT(5)
83 
84 /* INT1 and INT2 are in the opposite order as in INT_OUT_CTRL! */
85 #define BMI160_REG_INT_MAP		0x56
86 #define BMI160_INT1_MAP_DRDY_EN		0x80
87 #define BMI160_INT2_MAP_DRDY_EN		0x08
88 
89 #define BMI160_REG_DUMMY		0x7F
90 
91 #define BMI160_NORMAL_WRITE_USLEEP	2
92 #define BMI160_SUSPENDED_WRITE_USLEEP	450
93 
94 #define BMI160_ACCEL_PMU_MIN_USLEEP	3800
95 #define BMI160_GYRO_PMU_MIN_USLEEP	80000
96 #define BMI160_SOFTRESET_USLEEP		1000
97 
98 #define BMI160_CHANNEL(_type, _axis, _index) {			\
99 	.type = _type,						\
100 	.modified = 1,						\
101 	.channel2 = IIO_MOD_##_axis,				\
102 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
103 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |  \
104 		BIT(IIO_CHAN_INFO_SAMP_FREQ),			\
105 	.scan_index = _index,					\
106 	.scan_type = {						\
107 		.sign = 's',					\
108 		.realbits = 16,					\
109 		.storagebits = 16,				\
110 		.endianness = IIO_LE,				\
111 	},							\
112 }
113 
114 /* scan indexes follow DATA register order */
115 enum bmi160_scan_axis {
116 	BMI160_SCAN_EXT_MAGN_X = 0,
117 	BMI160_SCAN_EXT_MAGN_Y,
118 	BMI160_SCAN_EXT_MAGN_Z,
119 	BMI160_SCAN_RHALL,
120 	BMI160_SCAN_GYRO_X,
121 	BMI160_SCAN_GYRO_Y,
122 	BMI160_SCAN_GYRO_Z,
123 	BMI160_SCAN_ACCEL_X,
124 	BMI160_SCAN_ACCEL_Y,
125 	BMI160_SCAN_ACCEL_Z,
126 	BMI160_SCAN_TIMESTAMP,
127 };
128 
129 enum bmi160_sensor_type {
130 	BMI160_ACCEL	= 0,
131 	BMI160_GYRO,
132 	BMI160_EXT_MAGN,
133 	BMI160_NUM_SENSORS /* must be last */
134 };
135 
136 enum bmi160_int_pin {
137 	BMI160_PIN_INT1,
138 	BMI160_PIN_INT2
139 };
140 
141 const struct regmap_config bmi160_regmap_config = {
142 	.reg_bits = 8,
143 	.val_bits = 8,
144 };
145 EXPORT_SYMBOL(bmi160_regmap_config);
146 
147 struct bmi160_regs {
148 	u8 data; /* LSB byte register for X-axis */
149 	u8 config;
150 	u8 config_odr_mask;
151 	u8 config_bwp_mask;
152 	u8 range;
153 	u8 pmu_cmd_normal;
154 	u8 pmu_cmd_suspend;
155 };
156 
157 static struct bmi160_regs bmi160_regs[] = {
158 	[BMI160_ACCEL] = {
159 		.data	= BMI160_REG_DATA_ACCEL_XOUT_L,
160 		.config	= BMI160_REG_ACCEL_CONFIG,
161 		.config_odr_mask = BMI160_ACCEL_CONFIG_ODR_MASK,
162 		.config_bwp_mask = BMI160_ACCEL_CONFIG_BWP_MASK,
163 		.range	= BMI160_REG_ACCEL_RANGE,
164 		.pmu_cmd_normal = BMI160_CMD_ACCEL_PM_NORMAL,
165 		.pmu_cmd_suspend = BMI160_CMD_ACCEL_PM_SUSPEND,
166 	},
167 	[BMI160_GYRO] = {
168 		.data	= BMI160_REG_DATA_GYRO_XOUT_L,
169 		.config	= BMI160_REG_GYRO_CONFIG,
170 		.config_odr_mask = BMI160_GYRO_CONFIG_ODR_MASK,
171 		.config_bwp_mask = BMI160_GYRO_CONFIG_BWP_MASK,
172 		.range	= BMI160_REG_GYRO_RANGE,
173 		.pmu_cmd_normal = BMI160_CMD_GYRO_PM_NORMAL,
174 		.pmu_cmd_suspend = BMI160_CMD_GYRO_PM_SUSPEND,
175 	},
176 };
177 
178 static unsigned long bmi160_pmu_time[] = {
179 	[BMI160_ACCEL] = BMI160_ACCEL_PMU_MIN_USLEEP,
180 	[BMI160_GYRO] = BMI160_GYRO_PMU_MIN_USLEEP,
181 };
182 
183 struct bmi160_scale {
184 	u8 bits;
185 	int uscale;
186 };
187 
188 struct bmi160_odr {
189 	u8 bits;
190 	int odr;
191 	int uodr;
192 };
193 
194 static const struct bmi160_scale bmi160_accel_scale[] = {
195 	{ BMI160_ACCEL_RANGE_2G, 598},
196 	{ BMI160_ACCEL_RANGE_4G, 1197},
197 	{ BMI160_ACCEL_RANGE_8G, 2394},
198 	{ BMI160_ACCEL_RANGE_16G, 4788},
199 };
200 
201 static const struct bmi160_scale bmi160_gyro_scale[] = {
202 	{ BMI160_GYRO_RANGE_2000DPS, 1065},
203 	{ BMI160_GYRO_RANGE_1000DPS, 532},
204 	{ BMI160_GYRO_RANGE_500DPS, 266},
205 	{ BMI160_GYRO_RANGE_250DPS, 133},
206 	{ BMI160_GYRO_RANGE_125DPS, 66},
207 };
208 
209 struct bmi160_scale_item {
210 	const struct bmi160_scale *tbl;
211 	int num;
212 };
213 
214 static const struct  bmi160_scale_item bmi160_scale_table[] = {
215 	[BMI160_ACCEL] = {
216 		.tbl	= bmi160_accel_scale,
217 		.num	= ARRAY_SIZE(bmi160_accel_scale),
218 	},
219 	[BMI160_GYRO] = {
220 		.tbl	= bmi160_gyro_scale,
221 		.num	= ARRAY_SIZE(bmi160_gyro_scale),
222 	},
223 };
224 
225 static const struct bmi160_odr bmi160_accel_odr[] = {
226 	{0x01, 0, 781250},
227 	{0x02, 1, 562500},
228 	{0x03, 3, 125000},
229 	{0x04, 6, 250000},
230 	{0x05, 12, 500000},
231 	{0x06, 25, 0},
232 	{0x07, 50, 0},
233 	{0x08, 100, 0},
234 	{0x09, 200, 0},
235 	{0x0A, 400, 0},
236 	{0x0B, 800, 0},
237 	{0x0C, 1600, 0},
238 };
239 
240 static const struct bmi160_odr bmi160_gyro_odr[] = {
241 	{0x06, 25, 0},
242 	{0x07, 50, 0},
243 	{0x08, 100, 0},
244 	{0x09, 200, 0},
245 	{0x0A, 400, 0},
246 	{0x0B, 800, 0},
247 	{0x0C, 1600, 0},
248 	{0x0D, 3200, 0},
249 };
250 
251 struct bmi160_odr_item {
252 	const struct bmi160_odr *tbl;
253 	int num;
254 };
255 
256 static const struct  bmi160_odr_item bmi160_odr_table[] = {
257 	[BMI160_ACCEL] = {
258 		.tbl	= bmi160_accel_odr,
259 		.num	= ARRAY_SIZE(bmi160_accel_odr),
260 	},
261 	[BMI160_GYRO] = {
262 		.tbl	= bmi160_gyro_odr,
263 		.num	= ARRAY_SIZE(bmi160_gyro_odr),
264 	},
265 };
266 
267 static const struct iio_chan_spec bmi160_channels[] = {
268 	BMI160_CHANNEL(IIO_ACCEL, X, BMI160_SCAN_ACCEL_X),
269 	BMI160_CHANNEL(IIO_ACCEL, Y, BMI160_SCAN_ACCEL_Y),
270 	BMI160_CHANNEL(IIO_ACCEL, Z, BMI160_SCAN_ACCEL_Z),
271 	BMI160_CHANNEL(IIO_ANGL_VEL, X, BMI160_SCAN_GYRO_X),
272 	BMI160_CHANNEL(IIO_ANGL_VEL, Y, BMI160_SCAN_GYRO_Y),
273 	BMI160_CHANNEL(IIO_ANGL_VEL, Z, BMI160_SCAN_GYRO_Z),
274 	IIO_CHAN_SOFT_TIMESTAMP(BMI160_SCAN_TIMESTAMP),
275 };
276 
277 static enum bmi160_sensor_type bmi160_to_sensor(enum iio_chan_type iio_type)
278 {
279 	switch (iio_type) {
280 	case IIO_ACCEL:
281 		return BMI160_ACCEL;
282 	case IIO_ANGL_VEL:
283 		return BMI160_GYRO;
284 	default:
285 		return -EINVAL;
286 	}
287 }
288 
289 static
290 int bmi160_set_mode(struct bmi160_data *data, enum bmi160_sensor_type t,
291 		    bool mode)
292 {
293 	int ret;
294 	u8 cmd;
295 
296 	if (mode)
297 		cmd = bmi160_regs[t].pmu_cmd_normal;
298 	else
299 		cmd = bmi160_regs[t].pmu_cmd_suspend;
300 
301 	ret = regmap_write(data->regmap, BMI160_REG_CMD, cmd);
302 	if (ret)
303 		return ret;
304 
305 	usleep_range(bmi160_pmu_time[t], bmi160_pmu_time[t] + 1000);
306 
307 	return 0;
308 }
309 
310 static
311 int bmi160_set_scale(struct bmi160_data *data, enum bmi160_sensor_type t,
312 		     int uscale)
313 {
314 	int i;
315 
316 	for (i = 0; i < bmi160_scale_table[t].num; i++)
317 		if (bmi160_scale_table[t].tbl[i].uscale == uscale)
318 			break;
319 
320 	if (i == bmi160_scale_table[t].num)
321 		return -EINVAL;
322 
323 	return regmap_write(data->regmap, bmi160_regs[t].range,
324 			    bmi160_scale_table[t].tbl[i].bits);
325 }
326 
327 static
328 int bmi160_get_scale(struct bmi160_data *data, enum bmi160_sensor_type t,
329 		     int *uscale)
330 {
331 	int i, ret, val;
332 
333 	ret = regmap_read(data->regmap, bmi160_regs[t].range, &val);
334 	if (ret)
335 		return ret;
336 
337 	for (i = 0; i < bmi160_scale_table[t].num; i++)
338 		if (bmi160_scale_table[t].tbl[i].bits == val) {
339 			*uscale = bmi160_scale_table[t].tbl[i].uscale;
340 			return 0;
341 		}
342 
343 	return -EINVAL;
344 }
345 
346 static int bmi160_get_data(struct bmi160_data *data, int chan_type,
347 			   int axis, int *val)
348 {
349 	u8 reg;
350 	int ret;
351 	__le16 sample;
352 	enum bmi160_sensor_type t = bmi160_to_sensor(chan_type);
353 
354 	reg = bmi160_regs[t].data + (axis - IIO_MOD_X) * sizeof(sample);
355 
356 	ret = regmap_bulk_read(data->regmap, reg, &sample, sizeof(sample));
357 	if (ret)
358 		return ret;
359 
360 	*val = sign_extend32(le16_to_cpu(sample), 15);
361 
362 	return 0;
363 }
364 
365 static
366 int bmi160_set_odr(struct bmi160_data *data, enum bmi160_sensor_type t,
367 		   int odr, int uodr)
368 {
369 	int i;
370 
371 	for (i = 0; i < bmi160_odr_table[t].num; i++)
372 		if (bmi160_odr_table[t].tbl[i].odr == odr &&
373 		    bmi160_odr_table[t].tbl[i].uodr == uodr)
374 			break;
375 
376 	if (i >= bmi160_odr_table[t].num)
377 		return -EINVAL;
378 
379 	return regmap_update_bits(data->regmap,
380 				  bmi160_regs[t].config,
381 				  bmi160_regs[t].config_odr_mask,
382 				  bmi160_odr_table[t].tbl[i].bits);
383 }
384 
385 static int bmi160_get_odr(struct bmi160_data *data, enum bmi160_sensor_type t,
386 			  int *odr, int *uodr)
387 {
388 	int i, val, ret;
389 
390 	ret = regmap_read(data->regmap, bmi160_regs[t].config, &val);
391 	if (ret)
392 		return ret;
393 
394 	val &= bmi160_regs[t].config_odr_mask;
395 
396 	for (i = 0; i < bmi160_odr_table[t].num; i++)
397 		if (val == bmi160_odr_table[t].tbl[i].bits)
398 			break;
399 
400 	if (i >= bmi160_odr_table[t].num)
401 		return -EINVAL;
402 
403 	*odr = bmi160_odr_table[t].tbl[i].odr;
404 	*uodr = bmi160_odr_table[t].tbl[i].uodr;
405 
406 	return 0;
407 }
408 
409 static irqreturn_t bmi160_trigger_handler(int irq, void *p)
410 {
411 	struct iio_poll_func *pf = p;
412 	struct iio_dev *indio_dev = pf->indio_dev;
413 	struct bmi160_data *data = iio_priv(indio_dev);
414 	__le16 buf[16];
415 	/* 3 sens x 3 axis x __le16 + 3 x __le16 pad + 4 x __le16 tstamp */
416 	int i, ret, j = 0, base = BMI160_REG_DATA_MAGN_XOUT_L;
417 	__le16 sample;
418 
419 	for_each_set_bit(i, indio_dev->active_scan_mask,
420 			 indio_dev->masklength) {
421 		ret = regmap_bulk_read(data->regmap, base + i * sizeof(sample),
422 				       &sample, sizeof(sample));
423 		if (ret)
424 			goto done;
425 		buf[j++] = sample;
426 	}
427 
428 	iio_push_to_buffers_with_timestamp(indio_dev, buf, pf->timestamp);
429 done:
430 	iio_trigger_notify_done(indio_dev->trig);
431 	return IRQ_HANDLED;
432 }
433 
434 static int bmi160_read_raw(struct iio_dev *indio_dev,
435 			   struct iio_chan_spec const *chan,
436 			   int *val, int *val2, long mask)
437 {
438 	int ret;
439 	struct bmi160_data *data = iio_priv(indio_dev);
440 
441 	switch (mask) {
442 	case IIO_CHAN_INFO_RAW:
443 		ret = bmi160_get_data(data, chan->type, chan->channel2, val);
444 		if (ret)
445 			return ret;
446 		return IIO_VAL_INT;
447 	case IIO_CHAN_INFO_SCALE:
448 		*val = 0;
449 		ret = bmi160_get_scale(data,
450 				       bmi160_to_sensor(chan->type), val2);
451 		return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
452 	case IIO_CHAN_INFO_SAMP_FREQ:
453 		ret = bmi160_get_odr(data, bmi160_to_sensor(chan->type),
454 				     val, val2);
455 		return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
456 	default:
457 		return -EINVAL;
458 	}
459 
460 	return 0;
461 }
462 
463 static int bmi160_write_raw(struct iio_dev *indio_dev,
464 			    struct iio_chan_spec const *chan,
465 			    int val, int val2, long mask)
466 {
467 	struct bmi160_data *data = iio_priv(indio_dev);
468 
469 	switch (mask) {
470 	case IIO_CHAN_INFO_SCALE:
471 		return bmi160_set_scale(data,
472 					bmi160_to_sensor(chan->type), val2);
473 		break;
474 	case IIO_CHAN_INFO_SAMP_FREQ:
475 		return bmi160_set_odr(data, bmi160_to_sensor(chan->type),
476 				      val, val2);
477 	default:
478 		return -EINVAL;
479 	}
480 
481 	return 0;
482 }
483 
484 static
485 IIO_CONST_ATTR(in_accel_sampling_frequency_available,
486 	       "0.78125 1.5625 3.125 6.25 12.5 25 50 100 200 400 800 1600");
487 static
488 IIO_CONST_ATTR(in_anglvel_sampling_frequency_available,
489 	       "25 50 100 200 400 800 1600 3200");
490 static
491 IIO_CONST_ATTR(in_accel_scale_available,
492 	       "0.000598 0.001197 0.002394 0.004788");
493 static
494 IIO_CONST_ATTR(in_anglvel_scale_available,
495 	       "0.001065 0.000532 0.000266 0.000133 0.000066");
496 
497 static struct attribute *bmi160_attrs[] = {
498 	&iio_const_attr_in_accel_sampling_frequency_available.dev_attr.attr,
499 	&iio_const_attr_in_anglvel_sampling_frequency_available.dev_attr.attr,
500 	&iio_const_attr_in_accel_scale_available.dev_attr.attr,
501 	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
502 	NULL,
503 };
504 
505 static const struct attribute_group bmi160_attrs_group = {
506 	.attrs = bmi160_attrs,
507 };
508 
509 static const struct iio_info bmi160_info = {
510 	.read_raw = bmi160_read_raw,
511 	.write_raw = bmi160_write_raw,
512 	.attrs = &bmi160_attrs_group,
513 };
514 
515 static const char *bmi160_match_acpi_device(struct device *dev)
516 {
517 	const struct acpi_device_id *id;
518 
519 	id = acpi_match_device(dev->driver->acpi_match_table, dev);
520 	if (!id)
521 		return NULL;
522 
523 	return dev_name(dev);
524 }
525 
526 static int bmi160_write_conf_reg(struct regmap *regmap, unsigned int reg,
527 				 unsigned int mask, unsigned int bits,
528 				 unsigned int write_usleep)
529 {
530 	int ret;
531 	unsigned int val;
532 
533 	ret = regmap_read(regmap, reg, &val);
534 	if (ret)
535 		return ret;
536 
537 	val = (val & ~mask) | bits;
538 
539 	ret = regmap_write(regmap, reg, val);
540 	if (ret)
541 		return ret;
542 
543 	/*
544 	 * We need to wait after writing before we can write again. See the
545 	 * datasheet, page 93.
546 	 */
547 	usleep_range(write_usleep, write_usleep + 1000);
548 
549 	return 0;
550 }
551 
552 static int bmi160_config_pin(struct regmap *regmap, enum bmi160_int_pin pin,
553 			     bool open_drain, u8 irq_mask,
554 			     unsigned long write_usleep)
555 {
556 	int ret;
557 	struct device *dev = regmap_get_device(regmap);
558 	u8 int_out_ctrl_shift;
559 	u8 int_latch_mask;
560 	u8 int_map_mask;
561 	u8 int_out_ctrl_mask;
562 	u8 int_out_ctrl_bits;
563 	const char *pin_name;
564 
565 	switch (pin) {
566 	case BMI160_PIN_INT1:
567 		int_out_ctrl_shift = BMI160_INT1_OUT_CTRL_SHIFT;
568 		int_latch_mask = BMI160_INT1_LATCH_MASK;
569 		int_map_mask = BMI160_INT1_MAP_DRDY_EN;
570 		break;
571 	case BMI160_PIN_INT2:
572 		int_out_ctrl_shift = BMI160_INT2_OUT_CTRL_SHIFT;
573 		int_latch_mask = BMI160_INT2_LATCH_MASK;
574 		int_map_mask = BMI160_INT2_MAP_DRDY_EN;
575 		break;
576 	}
577 	int_out_ctrl_mask = BMI160_INT_OUT_CTRL_MASK << int_out_ctrl_shift;
578 
579 	/*
580 	 * Enable the requested pin with the right settings:
581 	 * - Push-pull/open-drain
582 	 * - Active low/high
583 	 * - Edge/level triggered
584 	 */
585 	int_out_ctrl_bits = BMI160_OUTPUT_EN;
586 	if (open_drain)
587 		/* Default is push-pull. */
588 		int_out_ctrl_bits |= BMI160_OPEN_DRAIN;
589 	int_out_ctrl_bits |= irq_mask;
590 	int_out_ctrl_bits <<= int_out_ctrl_shift;
591 
592 	ret = bmi160_write_conf_reg(regmap, BMI160_REG_INT_OUT_CTRL,
593 				    int_out_ctrl_mask, int_out_ctrl_bits,
594 				    write_usleep);
595 	if (ret)
596 		return ret;
597 
598 	/* Set the pin to input mode with no latching. */
599 	ret = bmi160_write_conf_reg(regmap, BMI160_REG_INT_LATCH,
600 				    int_latch_mask, int_latch_mask,
601 				    write_usleep);
602 	if (ret)
603 		return ret;
604 
605 	/* Map interrupts to the requested pin. */
606 	ret = bmi160_write_conf_reg(regmap, BMI160_REG_INT_MAP,
607 				    int_map_mask, int_map_mask,
608 				    write_usleep);
609 	if (ret) {
610 		switch (pin) {
611 		case BMI160_PIN_INT1:
612 			pin_name = "INT1";
613 			break;
614 		case BMI160_PIN_INT2:
615 			pin_name = "INT2";
616 			break;
617 		}
618 		dev_err(dev, "Failed to configure %s IRQ pin", pin_name);
619 	}
620 
621 	return ret;
622 }
623 
624 int bmi160_enable_irq(struct regmap *regmap, bool enable)
625 {
626 	unsigned int enable_bit = 0;
627 
628 	if (enable)
629 		enable_bit = BMI160_DRDY_INT_EN;
630 
631 	return bmi160_write_conf_reg(regmap, BMI160_REG_INT_EN,
632 				     BMI160_DRDY_INT_EN, enable_bit,
633 				     BMI160_NORMAL_WRITE_USLEEP);
634 }
635 EXPORT_SYMBOL(bmi160_enable_irq);
636 
637 static int bmi160_get_irq(struct device_node *of_node, enum bmi160_int_pin *pin)
638 {
639 	int irq;
640 
641 	/* Use INT1 if possible, otherwise fall back to INT2. */
642 	irq = of_irq_get_byname(of_node, "INT1");
643 	if (irq > 0) {
644 		*pin = BMI160_PIN_INT1;
645 		return irq;
646 	}
647 
648 	irq = of_irq_get_byname(of_node, "INT2");
649 	if (irq > 0)
650 		*pin = BMI160_PIN_INT2;
651 
652 	return irq;
653 }
654 
655 static int bmi160_config_device_irq(struct iio_dev *indio_dev, int irq_type,
656 				    enum bmi160_int_pin pin)
657 {
658 	bool open_drain;
659 	u8 irq_mask;
660 	struct bmi160_data *data = iio_priv(indio_dev);
661 	struct device *dev = regmap_get_device(data->regmap);
662 
663 	/* Level-triggered, active-low is the default if we set all zeroes. */
664 	if (irq_type == IRQF_TRIGGER_RISING)
665 		irq_mask = BMI160_ACTIVE_HIGH | BMI160_EDGE_TRIGGERED;
666 	else if (irq_type == IRQF_TRIGGER_FALLING)
667 		irq_mask = BMI160_EDGE_TRIGGERED;
668 	else if (irq_type == IRQF_TRIGGER_HIGH)
669 		irq_mask = BMI160_ACTIVE_HIGH;
670 	else if (irq_type == IRQF_TRIGGER_LOW)
671 		irq_mask = 0;
672 	else {
673 		dev_err(&indio_dev->dev,
674 			"Invalid interrupt type 0x%x specified\n", irq_type);
675 		return -EINVAL;
676 	}
677 
678 	open_drain = of_property_read_bool(dev->of_node, "drive-open-drain");
679 
680 	return bmi160_config_pin(data->regmap, pin, open_drain, irq_mask,
681 				 BMI160_NORMAL_WRITE_USLEEP);
682 }
683 
684 static int bmi160_setup_irq(struct iio_dev *indio_dev, int irq,
685 			    enum bmi160_int_pin pin)
686 {
687 	struct irq_data *desc;
688 	u32 irq_type;
689 	int ret;
690 
691 	desc = irq_get_irq_data(irq);
692 	if (!desc) {
693 		dev_err(&indio_dev->dev, "Could not find IRQ %d\n", irq);
694 		return -EINVAL;
695 	}
696 
697 	irq_type = irqd_get_trigger_type(desc);
698 
699 	ret = bmi160_config_device_irq(indio_dev, irq_type, pin);
700 	if (ret)
701 		return ret;
702 
703 	return bmi160_probe_trigger(indio_dev, irq, irq_type);
704 }
705 
706 static int bmi160_chip_init(struct bmi160_data *data, bool use_spi)
707 {
708 	int ret;
709 	unsigned int val;
710 	struct device *dev = regmap_get_device(data->regmap);
711 
712 	ret = regmap_write(data->regmap, BMI160_REG_CMD, BMI160_CMD_SOFTRESET);
713 	if (ret)
714 		return ret;
715 
716 	usleep_range(BMI160_SOFTRESET_USLEEP, BMI160_SOFTRESET_USLEEP + 1);
717 
718 	/*
719 	 * CS rising edge is needed before starting SPI, so do a dummy read
720 	 * See Section 3.2.1, page 86 of the datasheet
721 	 */
722 	if (use_spi) {
723 		ret = regmap_read(data->regmap, BMI160_REG_DUMMY, &val);
724 		if (ret)
725 			return ret;
726 	}
727 
728 	ret = regmap_read(data->regmap, BMI160_REG_CHIP_ID, &val);
729 	if (ret) {
730 		dev_err(dev, "Error reading chip id\n");
731 		return ret;
732 	}
733 	if (val != BMI160_CHIP_ID_VAL) {
734 		dev_err(dev, "Wrong chip id, got %x expected %x\n",
735 			val, BMI160_CHIP_ID_VAL);
736 		return -ENODEV;
737 	}
738 
739 	ret = bmi160_set_mode(data, BMI160_ACCEL, true);
740 	if (ret)
741 		return ret;
742 
743 	ret = bmi160_set_mode(data, BMI160_GYRO, true);
744 	if (ret)
745 		return ret;
746 
747 	return 0;
748 }
749 
750 static int bmi160_data_rdy_trigger_set_state(struct iio_trigger *trig,
751 					     bool enable)
752 {
753 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
754 	struct bmi160_data *data = iio_priv(indio_dev);
755 
756 	return bmi160_enable_irq(data->regmap, enable);
757 }
758 
759 static const struct iio_trigger_ops bmi160_trigger_ops = {
760 	.set_trigger_state = &bmi160_data_rdy_trigger_set_state,
761 };
762 
763 int bmi160_probe_trigger(struct iio_dev *indio_dev, int irq, u32 irq_type)
764 {
765 	struct bmi160_data *data = iio_priv(indio_dev);
766 	int ret;
767 
768 	data->trig = devm_iio_trigger_alloc(&indio_dev->dev, "%s-dev%d",
769 					    indio_dev->name, indio_dev->id);
770 
771 	if (data->trig == NULL)
772 		return -ENOMEM;
773 
774 	ret = devm_request_irq(&indio_dev->dev, irq,
775 			       &iio_trigger_generic_data_rdy_poll,
776 			       irq_type, "bmi160", data->trig);
777 	if (ret)
778 		return ret;
779 
780 	data->trig->dev.parent = regmap_get_device(data->regmap);
781 	data->trig->ops = &bmi160_trigger_ops;
782 	iio_trigger_set_drvdata(data->trig, indio_dev);
783 
784 	ret = devm_iio_trigger_register(&indio_dev->dev, data->trig);
785 	if (ret)
786 		return ret;
787 
788 	indio_dev->trig = iio_trigger_get(data->trig);
789 
790 	return 0;
791 }
792 
793 static void bmi160_chip_uninit(void *data)
794 {
795 	struct bmi160_data *bmi_data = data;
796 
797 	bmi160_set_mode(bmi_data, BMI160_GYRO, false);
798 	bmi160_set_mode(bmi_data, BMI160_ACCEL, false);
799 }
800 
801 int bmi160_core_probe(struct device *dev, struct regmap *regmap,
802 		      const char *name, bool use_spi)
803 {
804 	struct iio_dev *indio_dev;
805 	struct bmi160_data *data;
806 	int irq;
807 	enum bmi160_int_pin int_pin;
808 	int ret;
809 
810 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
811 	if (!indio_dev)
812 		return -ENOMEM;
813 
814 	data = iio_priv(indio_dev);
815 	dev_set_drvdata(dev, indio_dev);
816 	data->regmap = regmap;
817 
818 	ret = bmi160_chip_init(data, use_spi);
819 	if (ret)
820 		return ret;
821 
822 	ret = devm_add_action_or_reset(dev, bmi160_chip_uninit, data);
823 	if (ret)
824 		return ret;
825 
826 	if (!name && ACPI_HANDLE(dev))
827 		name = bmi160_match_acpi_device(dev);
828 
829 	indio_dev->dev.parent = dev;
830 	indio_dev->channels = bmi160_channels;
831 	indio_dev->num_channels = ARRAY_SIZE(bmi160_channels);
832 	indio_dev->name = name;
833 	indio_dev->modes = INDIO_DIRECT_MODE;
834 	indio_dev->info = &bmi160_info;
835 
836 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
837 					      iio_pollfunc_store_time,
838 					      bmi160_trigger_handler, NULL);
839 	if (ret)
840 		return ret;
841 
842 	irq = bmi160_get_irq(dev->of_node, &int_pin);
843 	if (irq > 0) {
844 		ret = bmi160_setup_irq(indio_dev, irq, int_pin);
845 		if (ret)
846 			dev_err(&indio_dev->dev, "Failed to setup IRQ %d\n",
847 				irq);
848 	} else {
849 		dev_info(&indio_dev->dev, "Not setting up IRQ trigger\n");
850 	}
851 
852 	return devm_iio_device_register(dev, indio_dev);
853 }
854 EXPORT_SYMBOL_GPL(bmi160_core_probe);
855 
856 MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com");
857 MODULE_DESCRIPTION("Bosch BMI160 driver");
858 MODULE_LICENSE("GPL v2");
859