1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for NXP FXAS21002C Gyroscope - Core
4  *
5  * Copyright (C) 2019 Linaro Ltd.
6  */
7 
8 #include <linux/interrupt.h>
9 #include <linux/module.h>
10 #include <linux/of_irq.h>
11 #include <linux/pm.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/regmap.h>
14 #include <linux/regulator/consumer.h>
15 
16 #include <linux/iio/events.h>
17 #include <linux/iio/iio.h>
18 #include <linux/iio/buffer.h>
19 #include <linux/iio/sysfs.h>
20 #include <linux/iio/trigger.h>
21 #include <linux/iio/trigger_consumer.h>
22 #include <linux/iio/triggered_buffer.h>
23 
24 #include "fxas21002c.h"
25 
26 #define FXAS21002C_CHIP_ID_1	0xD6
27 #define FXAS21002C_CHIP_ID_2	0xD7
28 
29 enum fxas21002c_mode_state {
30 	FXAS21002C_MODE_STANDBY,
31 	FXAS21002C_MODE_READY,
32 	FXAS21002C_MODE_ACTIVE,
33 };
34 
35 #define FXAS21002C_STANDBY_ACTIVE_TIME_MS	62
36 #define FXAS21002C_READY_ACTIVE_TIME_MS		7
37 
38 #define FXAS21002C_ODR_LIST_MAX		10
39 
40 #define FXAS21002C_SCALE_FRACTIONAL	32
41 #define FXAS21002C_RANGE_LIMIT_DOUBLE	2000
42 
43 #define FXAS21002C_AXIS_TO_REG(axis) (FXAS21002C_REG_OUT_X_MSB + ((axis) * 2))
44 
45 static const struct reg_field fxas21002c_reg_fields[] = {
46 	[F_DR_STATUS]		= REG_FIELD(FXAS21002C_REG_STATUS, 0, 7),
47 	[F_OUT_X_MSB]		= REG_FIELD(FXAS21002C_REG_OUT_X_MSB, 0, 7),
48 	[F_OUT_X_LSB]		= REG_FIELD(FXAS21002C_REG_OUT_X_LSB, 0, 7),
49 	[F_OUT_Y_MSB]		= REG_FIELD(FXAS21002C_REG_OUT_Y_MSB, 0, 7),
50 	[F_OUT_Y_LSB]		= REG_FIELD(FXAS21002C_REG_OUT_Y_LSB, 0, 7),
51 	[F_OUT_Z_MSB]		= REG_FIELD(FXAS21002C_REG_OUT_Z_MSB, 0, 7),
52 	[F_OUT_Z_LSB]		= REG_FIELD(FXAS21002C_REG_OUT_Z_LSB, 0, 7),
53 	[F_ZYX_OW]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 7, 7),
54 	[F_Z_OW]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 6, 6),
55 	[F_Y_OW]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 5, 5),
56 	[F_X_OW]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 4, 4),
57 	[F_ZYX_DR]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 3, 3),
58 	[F_Z_DR]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 2, 2),
59 	[F_Y_DR]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 1, 1),
60 	[F_X_DR]		= REG_FIELD(FXAS21002C_REG_DR_STATUS, 0, 0),
61 	[F_OVF]			= REG_FIELD(FXAS21002C_REG_F_STATUS, 7, 7),
62 	[F_WMKF]		= REG_FIELD(FXAS21002C_REG_F_STATUS, 6, 6),
63 	[F_CNT]			= REG_FIELD(FXAS21002C_REG_F_STATUS, 0, 5),
64 	[F_MODE]		= REG_FIELD(FXAS21002C_REG_F_SETUP, 6, 7),
65 	[F_WMRK]		= REG_FIELD(FXAS21002C_REG_F_SETUP, 0, 5),
66 	[F_EVENT]		= REG_FIELD(FXAS21002C_REG_F_EVENT, 5, 5),
67 	[FE_TIME]		= REG_FIELD(FXAS21002C_REG_F_EVENT, 0, 4),
68 	[F_BOOTEND]		= REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 3, 3),
69 	[F_SRC_FIFO]		= REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 2, 2),
70 	[F_SRC_RT]		= REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 1, 1),
71 	[F_SRC_DRDY]		= REG_FIELD(FXAS21002C_REG_INT_SRC_FLAG, 0, 0),
72 	[F_WHO_AM_I]		= REG_FIELD(FXAS21002C_REG_WHO_AM_I, 0, 7),
73 	[F_BW]			= REG_FIELD(FXAS21002C_REG_CTRL0, 6, 7),
74 	[F_SPIW]		= REG_FIELD(FXAS21002C_REG_CTRL0, 5, 5),
75 	[F_SEL]			= REG_FIELD(FXAS21002C_REG_CTRL0, 3, 4),
76 	[F_HPF_EN]		= REG_FIELD(FXAS21002C_REG_CTRL0, 2, 2),
77 	[F_FS]			= REG_FIELD(FXAS21002C_REG_CTRL0, 0, 1),
78 	[F_ELE]			= REG_FIELD(FXAS21002C_REG_RT_CFG, 3, 3),
79 	[F_ZTEFE]		= REG_FIELD(FXAS21002C_REG_RT_CFG, 2, 2),
80 	[F_YTEFE]		= REG_FIELD(FXAS21002C_REG_RT_CFG, 1, 1),
81 	[F_XTEFE]		= REG_FIELD(FXAS21002C_REG_RT_CFG, 0, 0),
82 	[F_EA]			= REG_FIELD(FXAS21002C_REG_RT_SRC, 6, 6),
83 	[F_ZRT]			= REG_FIELD(FXAS21002C_REG_RT_SRC, 5, 5),
84 	[F_ZRT_POL]		= REG_FIELD(FXAS21002C_REG_RT_SRC, 4, 4),
85 	[F_YRT]			= REG_FIELD(FXAS21002C_REG_RT_SRC, 3, 3),
86 	[F_YRT_POL]		= REG_FIELD(FXAS21002C_REG_RT_SRC, 2, 2),
87 	[F_XRT]			= REG_FIELD(FXAS21002C_REG_RT_SRC, 1, 1),
88 	[F_XRT_POL]		= REG_FIELD(FXAS21002C_REG_RT_SRC, 0, 0),
89 	[F_DBCNTM]		= REG_FIELD(FXAS21002C_REG_RT_THS, 7, 7),
90 	[F_THS]			= REG_FIELD(FXAS21002C_REG_RT_SRC, 0, 6),
91 	[F_RT_COUNT]		= REG_FIELD(FXAS21002C_REG_RT_COUNT, 0, 7),
92 	[F_TEMP]		= REG_FIELD(FXAS21002C_REG_TEMP, 0, 7),
93 	[F_RST]			= REG_FIELD(FXAS21002C_REG_CTRL1, 6, 6),
94 	[F_ST]			= REG_FIELD(FXAS21002C_REG_CTRL1, 5, 5),
95 	[F_DR]			= REG_FIELD(FXAS21002C_REG_CTRL1, 2, 4),
96 	[F_ACTIVE]		= REG_FIELD(FXAS21002C_REG_CTRL1, 1, 1),
97 	[F_READY]		= REG_FIELD(FXAS21002C_REG_CTRL1, 0, 0),
98 	[F_INT_CFG_FIFO]	= REG_FIELD(FXAS21002C_REG_CTRL2, 7, 7),
99 	[F_INT_EN_FIFO]		= REG_FIELD(FXAS21002C_REG_CTRL2, 6, 6),
100 	[F_INT_CFG_RT]		= REG_FIELD(FXAS21002C_REG_CTRL2, 5, 5),
101 	[F_INT_EN_RT]		= REG_FIELD(FXAS21002C_REG_CTRL2, 4, 4),
102 	[F_INT_CFG_DRDY]	= REG_FIELD(FXAS21002C_REG_CTRL2, 3, 3),
103 	[F_INT_EN_DRDY]		= REG_FIELD(FXAS21002C_REG_CTRL2, 2, 2),
104 	[F_IPOL]		= REG_FIELD(FXAS21002C_REG_CTRL2, 1, 1),
105 	[F_PP_OD]		= REG_FIELD(FXAS21002C_REG_CTRL2, 0, 0),
106 	[F_WRAPTOONE]		= REG_FIELD(FXAS21002C_REG_CTRL3, 3, 3),
107 	[F_EXTCTRLEN]		= REG_FIELD(FXAS21002C_REG_CTRL3, 2, 2),
108 	[F_FS_DOUBLE]		= REG_FIELD(FXAS21002C_REG_CTRL3, 0, 0),
109 };
110 
111 static const int fxas21002c_odr_values[] = {
112 	800, 400, 200, 100, 50, 25, 12, 12
113 };
114 
115 /*
116  * These values are taken from the low-pass filter cutoff frequency calculated
117  * ODR * 0.lpf_values. So, for ODR = 800Hz with a lpf value = 0.32
118  * => LPF cutoff frequency = 800 * 0.32 = 256 Hz
119  */
120 static const int fxas21002c_lpf_values[] = {
121 	32, 16, 8
122 };
123 
124 /*
125  * These values are taken from the high-pass filter cutoff frequency calculated
126  * ODR * 0.0hpf_values. So, for ODR = 800Hz with a hpf value = 0.018750
127  * => HPF cutoff frequency = 800 * 0.018750 = 15 Hz
128  */
129 static const int fxas21002c_hpf_values[] = {
130 	18750, 9625, 4875, 2475
131 };
132 
133 static const int fxas21002c_range_values[] = {
134 	4000, 2000, 1000, 500, 250
135 };
136 
137 struct fxas21002c_data {
138 	u8 chip_id;
139 	enum fxas21002c_mode_state mode;
140 	enum fxas21002c_mode_state prev_mode;
141 
142 	struct mutex lock;		/* serialize data access */
143 	struct regmap *regmap;
144 	struct regmap_field *regmap_fields[F_MAX_FIELDS];
145 	struct iio_trigger *dready_trig;
146 	s64 timestamp;
147 	int irq;
148 
149 	struct regulator *vdd;
150 	struct regulator *vddio;
151 
152 	/*
153 	 * DMA (thus cache coherency maintenance) requires the
154 	 * transfer buffers to live in their own cache lines.
155 	 */
156 	s16 buffer[8] ____cacheline_aligned;
157 };
158 
159 enum fxas21002c_channel_index {
160 	CHANNEL_SCAN_INDEX_X,
161 	CHANNEL_SCAN_INDEX_Y,
162 	CHANNEL_SCAN_INDEX_Z,
163 	CHANNEL_SCAN_MAX,
164 };
165 
166 static int fxas21002c_odr_hz_from_value(struct fxas21002c_data *data, u8 value)
167 {
168 	int odr_value_max = ARRAY_SIZE(fxas21002c_odr_values) - 1;
169 
170 	value = min_t(u8, value, odr_value_max);
171 
172 	return fxas21002c_odr_values[value];
173 }
174 
175 static int fxas21002c_odr_value_from_hz(struct fxas21002c_data *data,
176 					unsigned int hz)
177 {
178 	int odr_table_size = ARRAY_SIZE(fxas21002c_odr_values);
179 	int i;
180 
181 	for (i = 0; i < odr_table_size; i++)
182 		if (fxas21002c_odr_values[i] == hz)
183 			return i;
184 
185 	return -EINVAL;
186 }
187 
188 static int fxas21002c_lpf_bw_from_value(struct fxas21002c_data *data, u8 value)
189 {
190 	int lpf_value_max = ARRAY_SIZE(fxas21002c_lpf_values) - 1;
191 
192 	value = min_t(u8, value, lpf_value_max);
193 
194 	return fxas21002c_lpf_values[value];
195 }
196 
197 static int fxas21002c_lpf_value_from_bw(struct fxas21002c_data *data,
198 					unsigned int hz)
199 {
200 	int lpf_table_size = ARRAY_SIZE(fxas21002c_lpf_values);
201 	int i;
202 
203 	for (i = 0; i < lpf_table_size; i++)
204 		if (fxas21002c_lpf_values[i] == hz)
205 			return i;
206 
207 	return -EINVAL;
208 }
209 
210 static int fxas21002c_hpf_sel_from_value(struct fxas21002c_data *data, u8 value)
211 {
212 	int hpf_value_max = ARRAY_SIZE(fxas21002c_hpf_values) - 1;
213 
214 	value = min_t(u8, value, hpf_value_max);
215 
216 	return fxas21002c_hpf_values[value];
217 }
218 
219 static int fxas21002c_hpf_value_from_sel(struct fxas21002c_data *data,
220 					 unsigned int hz)
221 {
222 	int hpf_table_size = ARRAY_SIZE(fxas21002c_hpf_values);
223 	int i;
224 
225 	for (i = 0; i < hpf_table_size; i++)
226 		if (fxas21002c_hpf_values[i] == hz)
227 			return i;
228 
229 	return -EINVAL;
230 }
231 
232 static int fxas21002c_range_fs_from_value(struct fxas21002c_data *data,
233 					  u8 value)
234 {
235 	int range_value_max = ARRAY_SIZE(fxas21002c_range_values) - 1;
236 	unsigned int fs_double;
237 	int ret;
238 
239 	/* We need to check if FS_DOUBLE is enabled to offset the value */
240 	ret = regmap_field_read(data->regmap_fields[F_FS_DOUBLE], &fs_double);
241 	if (ret < 0)
242 		return ret;
243 
244 	if (!fs_double)
245 		value += 1;
246 
247 	value = min_t(u8, value, range_value_max);
248 
249 	return fxas21002c_range_values[value];
250 }
251 
252 static int fxas21002c_range_value_from_fs(struct fxas21002c_data *data,
253 					  unsigned int range)
254 {
255 	int range_table_size = ARRAY_SIZE(fxas21002c_range_values);
256 	bool found = false;
257 	int fs_double = 0;
258 	int ret;
259 	int i;
260 
261 	for (i = 0; i < range_table_size; i++)
262 		if (fxas21002c_range_values[i] == range) {
263 			found = true;
264 			break;
265 		}
266 
267 	if (!found)
268 		return -EINVAL;
269 
270 	if (range > FXAS21002C_RANGE_LIMIT_DOUBLE)
271 		fs_double = 1;
272 
273 	ret = regmap_field_write(data->regmap_fields[F_FS_DOUBLE], fs_double);
274 	if (ret < 0)
275 		return ret;
276 
277 	return i;
278 }
279 
280 static int fxas21002c_mode_get(struct fxas21002c_data *data)
281 {
282 	unsigned int active;
283 	unsigned int ready;
284 	int ret;
285 
286 	ret = regmap_field_read(data->regmap_fields[F_ACTIVE], &active);
287 	if (ret < 0)
288 		return ret;
289 	if (active)
290 		return FXAS21002C_MODE_ACTIVE;
291 
292 	ret = regmap_field_read(data->regmap_fields[F_READY], &ready);
293 	if (ret < 0)
294 		return ret;
295 	if (ready)
296 		return FXAS21002C_MODE_READY;
297 
298 	return FXAS21002C_MODE_STANDBY;
299 }
300 
301 static int fxas21002c_mode_set(struct fxas21002c_data *data,
302 			       enum fxas21002c_mode_state mode)
303 {
304 	int ret;
305 
306 	if (mode == data->mode)
307 		return 0;
308 
309 	if (mode == FXAS21002C_MODE_READY)
310 		ret = regmap_field_write(data->regmap_fields[F_READY], 1);
311 	else
312 		ret = regmap_field_write(data->regmap_fields[F_READY], 0);
313 	if (ret < 0)
314 		return ret;
315 
316 	if (mode == FXAS21002C_MODE_ACTIVE)
317 		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 1);
318 	else
319 		ret = regmap_field_write(data->regmap_fields[F_ACTIVE], 0);
320 	if (ret < 0)
321 		return ret;
322 
323 	/* if going to active wait the setup times */
324 	if (mode == FXAS21002C_MODE_ACTIVE &&
325 	    data->mode == FXAS21002C_MODE_STANDBY)
326 		msleep_interruptible(FXAS21002C_STANDBY_ACTIVE_TIME_MS);
327 
328 	if (data->mode == FXAS21002C_MODE_READY)
329 		msleep_interruptible(FXAS21002C_READY_ACTIVE_TIME_MS);
330 
331 	data->prev_mode = data->mode;
332 	data->mode = mode;
333 
334 	return ret;
335 }
336 
337 static int fxas21002c_write(struct fxas21002c_data *data,
338 			    enum fxas21002c_fields field, int bits)
339 {
340 	int actual_mode;
341 	int ret;
342 
343 	mutex_lock(&data->lock);
344 
345 	actual_mode = fxas21002c_mode_get(data);
346 	if (actual_mode < 0) {
347 		ret = actual_mode;
348 		goto out_unlock;
349 	}
350 
351 	ret = fxas21002c_mode_set(data, FXAS21002C_MODE_READY);
352 	if (ret < 0)
353 		goto out_unlock;
354 
355 	ret = regmap_field_write(data->regmap_fields[field], bits);
356 	if (ret < 0)
357 		goto out_unlock;
358 
359 	ret = fxas21002c_mode_set(data, data->prev_mode);
360 
361 out_unlock:
362 	mutex_unlock(&data->lock);
363 
364 	return ret;
365 }
366 
367 static int  fxas21002c_pm_get(struct fxas21002c_data *data)
368 {
369 	struct device *dev = regmap_get_device(data->regmap);
370 	int ret;
371 
372 	ret = pm_runtime_get_sync(dev);
373 	if (ret < 0)
374 		pm_runtime_put_noidle(dev);
375 
376 	return ret;
377 }
378 
379 static int  fxas21002c_pm_put(struct fxas21002c_data *data)
380 {
381 	struct device *dev = regmap_get_device(data->regmap);
382 
383 	pm_runtime_mark_last_busy(dev);
384 
385 	return pm_runtime_put_autosuspend(dev);
386 }
387 
388 static int fxas21002c_temp_get(struct fxas21002c_data *data, int *val)
389 {
390 	struct device *dev = regmap_get_device(data->regmap);
391 	unsigned int temp;
392 	int ret;
393 
394 	mutex_lock(&data->lock);
395 	ret = fxas21002c_pm_get(data);
396 	if (ret < 0)
397 		goto data_unlock;
398 
399 	ret = regmap_field_read(data->regmap_fields[F_TEMP], &temp);
400 	if (ret < 0) {
401 		dev_err(dev, "failed to read temp: %d\n", ret);
402 		goto data_unlock;
403 	}
404 
405 	*val = sign_extend32(temp, 7);
406 
407 	ret = fxas21002c_pm_put(data);
408 	if (ret < 0)
409 		goto data_unlock;
410 
411 	ret = IIO_VAL_INT;
412 
413 data_unlock:
414 	mutex_unlock(&data->lock);
415 
416 	return ret;
417 }
418 
419 static int fxas21002c_axis_get(struct fxas21002c_data *data,
420 			       int index, int *val)
421 {
422 	struct device *dev = regmap_get_device(data->regmap);
423 	__be16 axis_be;
424 	int ret;
425 
426 	mutex_lock(&data->lock);
427 	ret = fxas21002c_pm_get(data);
428 	if (ret < 0)
429 		goto data_unlock;
430 
431 	ret = regmap_bulk_read(data->regmap, FXAS21002C_AXIS_TO_REG(index),
432 			       &axis_be, sizeof(axis_be));
433 	if (ret < 0) {
434 		dev_err(dev, "failed to read axis: %d: %d\n", index, ret);
435 		goto data_unlock;
436 	}
437 
438 	*val = sign_extend32(be16_to_cpu(axis_be), 15);
439 
440 	ret = fxas21002c_pm_put(data);
441 	if (ret < 0)
442 		goto data_unlock;
443 
444 	ret = IIO_VAL_INT;
445 
446 data_unlock:
447 	mutex_unlock(&data->lock);
448 
449 	return ret;
450 }
451 
452 static int fxas21002c_odr_get(struct fxas21002c_data *data, int *odr)
453 {
454 	unsigned int odr_bits;
455 	int ret;
456 
457 	mutex_lock(&data->lock);
458 	ret = regmap_field_read(data->regmap_fields[F_DR], &odr_bits);
459 	if (ret < 0)
460 		goto data_unlock;
461 
462 	*odr = fxas21002c_odr_hz_from_value(data, odr_bits);
463 
464 	ret = IIO_VAL_INT;
465 
466 data_unlock:
467 	mutex_unlock(&data->lock);
468 
469 	return ret;
470 }
471 
472 static int fxas21002c_odr_set(struct fxas21002c_data *data, int odr)
473 {
474 	int odr_bits;
475 
476 	odr_bits = fxas21002c_odr_value_from_hz(data, odr);
477 	if (odr_bits < 0)
478 		return odr_bits;
479 
480 	return fxas21002c_write(data, F_DR, odr_bits);
481 }
482 
483 static int fxas21002c_lpf_get(struct fxas21002c_data *data, int *val2)
484 {
485 	unsigned int bw_bits;
486 	int ret;
487 
488 	mutex_lock(&data->lock);
489 	ret = regmap_field_read(data->regmap_fields[F_BW], &bw_bits);
490 	if (ret < 0)
491 		goto data_unlock;
492 
493 	*val2 = fxas21002c_lpf_bw_from_value(data, bw_bits) * 10000;
494 
495 	ret = IIO_VAL_INT_PLUS_MICRO;
496 
497 data_unlock:
498 	mutex_unlock(&data->lock);
499 
500 	return ret;
501 }
502 
503 static int fxas21002c_lpf_set(struct fxas21002c_data *data, int bw)
504 {
505 	int bw_bits;
506 	int odr;
507 	int ret;
508 
509 	bw_bits = fxas21002c_lpf_value_from_bw(data, bw);
510 	if (bw_bits < 0)
511 		return bw_bits;
512 
513 	/*
514 	 * From table 33 of the device spec, for ODR = 25Hz and 12.5 value 0.08
515 	 * is not allowed and for ODR = 12.5 value 0.16 is also not allowed
516 	 */
517 	ret = fxas21002c_odr_get(data, &odr);
518 	if (ret < 0)
519 		return -EINVAL;
520 
521 	if ((odr == 25 && bw_bits > 0x01) || (odr == 12 && bw_bits > 0))
522 		return -EINVAL;
523 
524 	return fxas21002c_write(data, F_BW, bw_bits);
525 }
526 
527 static int fxas21002c_hpf_get(struct fxas21002c_data *data, int *val2)
528 {
529 	unsigned int sel_bits;
530 	int ret;
531 
532 	mutex_lock(&data->lock);
533 	ret = regmap_field_read(data->regmap_fields[F_SEL], &sel_bits);
534 	if (ret < 0)
535 		goto data_unlock;
536 
537 	*val2 = fxas21002c_hpf_sel_from_value(data, sel_bits);
538 
539 	ret = IIO_VAL_INT_PLUS_MICRO;
540 
541 data_unlock:
542 	mutex_unlock(&data->lock);
543 
544 	return ret;
545 }
546 
547 static int fxas21002c_hpf_set(struct fxas21002c_data *data, int sel)
548 {
549 	int sel_bits;
550 
551 	sel_bits = fxas21002c_hpf_value_from_sel(data, sel);
552 	if (sel_bits < 0)
553 		return sel_bits;
554 
555 	return fxas21002c_write(data, F_SEL, sel_bits);
556 }
557 
558 static int fxas21002c_scale_get(struct fxas21002c_data *data, int *val)
559 {
560 	int fs_bits;
561 	int scale;
562 	int ret;
563 
564 	mutex_lock(&data->lock);
565 	ret = regmap_field_read(data->regmap_fields[F_FS], &fs_bits);
566 	if (ret < 0)
567 		goto data_unlock;
568 
569 	scale = fxas21002c_range_fs_from_value(data, fs_bits);
570 	if (scale < 0) {
571 		ret = scale;
572 		goto data_unlock;
573 	}
574 
575 	*val = scale;
576 
577 data_unlock:
578 	mutex_unlock(&data->lock);
579 
580 	return ret;
581 }
582 
583 static int fxas21002c_scale_set(struct fxas21002c_data *data, int range)
584 {
585 	int fs_bits;
586 
587 	fs_bits = fxas21002c_range_value_from_fs(data, range);
588 	if (fs_bits < 0)
589 		return fs_bits;
590 
591 	return fxas21002c_write(data, F_FS, fs_bits);
592 }
593 
594 static int fxas21002c_read_raw(struct iio_dev *indio_dev,
595 			       struct iio_chan_spec const *chan, int *val,
596 			       int *val2, long mask)
597 {
598 	struct fxas21002c_data *data = iio_priv(indio_dev);
599 	int ret;
600 
601 	switch (mask) {
602 	case IIO_CHAN_INFO_RAW:
603 		switch (chan->type) {
604 		case IIO_TEMP:
605 			return fxas21002c_temp_get(data, val);
606 		case IIO_ANGL_VEL:
607 			return fxas21002c_axis_get(data, chan->scan_index, val);
608 		default:
609 			return -EINVAL;
610 		}
611 	case IIO_CHAN_INFO_SCALE:
612 		switch (chan->type) {
613 		case IIO_ANGL_VEL:
614 			*val2 = FXAS21002C_SCALE_FRACTIONAL;
615 			ret = fxas21002c_scale_get(data, val);
616 			if (ret < 0)
617 				return ret;
618 
619 			return IIO_VAL_FRACTIONAL;
620 		default:
621 			return -EINVAL;
622 		}
623 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
624 		*val = 0;
625 		return fxas21002c_lpf_get(data, val2);
626 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
627 		*val = 0;
628 		return fxas21002c_hpf_get(data, val2);
629 	case IIO_CHAN_INFO_SAMP_FREQ:
630 		*val2 = 0;
631 		return fxas21002c_odr_get(data, val);
632 	default:
633 		return -EINVAL;
634 	}
635 }
636 
637 static int fxas21002c_write_raw(struct iio_dev *indio_dev,
638 				struct iio_chan_spec const *chan, int val,
639 				int val2, long mask)
640 {
641 	struct fxas21002c_data *data = iio_priv(indio_dev);
642 	int range;
643 
644 	switch (mask) {
645 	case IIO_CHAN_INFO_SAMP_FREQ:
646 		if (val2)
647 			return -EINVAL;
648 
649 		return fxas21002c_odr_set(data, val);
650 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
651 		if (val)
652 			return -EINVAL;
653 
654 		val2 = val2 / 10000;
655 		return fxas21002c_lpf_set(data, val2);
656 	case IIO_CHAN_INFO_SCALE:
657 		switch (chan->type) {
658 		case IIO_ANGL_VEL:
659 			range = (((val * 1000 + val2 / 1000) *
660 				  FXAS21002C_SCALE_FRACTIONAL) / 1000);
661 			return fxas21002c_scale_set(data, range);
662 		default:
663 			return -EINVAL;
664 		}
665 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
666 		return fxas21002c_hpf_set(data, val2);
667 	default:
668 		return -EINVAL;
669 	}
670 }
671 
672 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("12.5 25 50 100 200 400 800");
673 
674 static IIO_CONST_ATTR(in_anglvel_filter_low_pass_3db_frequency_available,
675 		      "0.32 0.16 0.08");
676 
677 static IIO_CONST_ATTR(in_anglvel_filter_high_pass_3db_frequency_available,
678 		      "0.018750 0.009625 0.004875 0.002475");
679 
680 static IIO_CONST_ATTR(in_anglvel_scale_available,
681 		      "125.0 62.5 31.25 15.625 7.8125");
682 
683 static struct attribute *fxas21002c_attributes[] = {
684 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
685 	&iio_const_attr_in_anglvel_filter_low_pass_3db_frequency_available.dev_attr.attr,
686 	&iio_const_attr_in_anglvel_filter_high_pass_3db_frequency_available.dev_attr.attr,
687 	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
688 	NULL,
689 };
690 
691 static const struct attribute_group fxas21002c_attrs_group = {
692 	.attrs = fxas21002c_attributes,
693 };
694 
695 #define FXAS21002C_CHANNEL(_axis) {					\
696 	.type = IIO_ANGL_VEL,						\
697 	.modified = 1,							\
698 	.channel2 = IIO_MOD_##_axis,					\
699 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
700 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
701 		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |	\
702 		BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY) |	\
703 		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
704 	.scan_index = CHANNEL_SCAN_INDEX_##_axis,			\
705 	.scan_type = {							\
706 		.sign = 's',						\
707 		.realbits = 16,						\
708 		.storagebits = 16,					\
709 		.endianness = IIO_BE,					\
710 	},								\
711 }
712 
713 static const struct iio_chan_spec fxas21002c_channels[] = {
714 	{
715 		.type = IIO_TEMP,
716 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
717 		.scan_index = -1,
718 	},
719 	FXAS21002C_CHANNEL(X),
720 	FXAS21002C_CHANNEL(Y),
721 	FXAS21002C_CHANNEL(Z),
722 };
723 
724 static const struct iio_info fxas21002c_info = {
725 	.attrs			= &fxas21002c_attrs_group,
726 	.read_raw		= &fxas21002c_read_raw,
727 	.write_raw		= &fxas21002c_write_raw,
728 };
729 
730 static irqreturn_t fxas21002c_trigger_handler(int irq, void *p)
731 {
732 	struct iio_poll_func *pf = p;
733 	struct iio_dev *indio_dev = pf->indio_dev;
734 	struct fxas21002c_data *data = iio_priv(indio_dev);
735 	int ret;
736 
737 	mutex_lock(&data->lock);
738 	ret = regmap_bulk_read(data->regmap, FXAS21002C_REG_OUT_X_MSB,
739 			       data->buffer, CHANNEL_SCAN_MAX * sizeof(s16));
740 	if (ret < 0)
741 		goto out_unlock;
742 
743 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
744 					   data->timestamp);
745 
746 out_unlock:
747 	mutex_unlock(&data->lock);
748 
749 	iio_trigger_notify_done(indio_dev->trig);
750 
751 	return IRQ_HANDLED;
752 }
753 
754 static int fxas21002c_chip_init(struct fxas21002c_data *data)
755 {
756 	struct device *dev = regmap_get_device(data->regmap);
757 	unsigned int chip_id;
758 	int ret;
759 
760 	ret = regmap_field_read(data->regmap_fields[F_WHO_AM_I], &chip_id);
761 	if (ret < 0)
762 		return ret;
763 
764 	if (chip_id != FXAS21002C_CHIP_ID_1 &&
765 	    chip_id != FXAS21002C_CHIP_ID_2) {
766 		dev_err(dev, "chip id 0x%02x is not supported\n", chip_id);
767 		return -EINVAL;
768 	}
769 
770 	data->chip_id = chip_id;
771 
772 	ret = fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
773 	if (ret < 0)
774 		return ret;
775 
776 	/* Set ODR to 200HZ as default */
777 	ret = fxas21002c_odr_set(data, 200);
778 	if (ret < 0)
779 		dev_err(dev, "failed to set ODR: %d\n", ret);
780 
781 	return ret;
782 }
783 
784 static int fxas21002c_data_rdy_trigger_set_state(struct iio_trigger *trig,
785 						 bool state)
786 {
787 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
788 	struct fxas21002c_data *data = iio_priv(indio_dev);
789 
790 	return regmap_field_write(data->regmap_fields[F_INT_EN_DRDY], state);
791 }
792 
793 static const struct iio_trigger_ops fxas21002c_trigger_ops = {
794 	.set_trigger_state = &fxas21002c_data_rdy_trigger_set_state,
795 };
796 
797 static irqreturn_t fxas21002c_data_rdy_handler(int irq, void *private)
798 {
799 	struct iio_dev *indio_dev = private;
800 	struct fxas21002c_data *data = iio_priv(indio_dev);
801 
802 	data->timestamp = iio_get_time_ns(indio_dev);
803 
804 	return IRQ_WAKE_THREAD;
805 }
806 
807 static irqreturn_t fxas21002c_data_rdy_thread(int irq, void *private)
808 {
809 	struct iio_dev *indio_dev = private;
810 	struct fxas21002c_data *data = iio_priv(indio_dev);
811 	unsigned int data_ready;
812 	int ret;
813 
814 	ret = regmap_field_read(data->regmap_fields[F_SRC_DRDY], &data_ready);
815 	if (ret < 0)
816 		return IRQ_NONE;
817 
818 	if (!data_ready)
819 		return IRQ_NONE;
820 
821 	iio_trigger_poll_chained(data->dready_trig);
822 
823 	return IRQ_HANDLED;
824 }
825 
826 static int fxas21002c_trigger_probe(struct fxas21002c_data *data)
827 {
828 	struct device *dev = regmap_get_device(data->regmap);
829 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
830 	struct device_node *np = indio_dev->dev.of_node;
831 	unsigned long irq_trig;
832 	bool irq_open_drain;
833 	int irq1;
834 	int ret;
835 
836 	if (!data->irq)
837 		return 0;
838 
839 	irq1 = of_irq_get_byname(np, "INT1");
840 
841 	if (irq1 == data->irq) {
842 		dev_info(dev, "using interrupt line INT1\n");
843 		ret = regmap_field_write(data->regmap_fields[F_INT_CFG_DRDY],
844 					 1);
845 		if (ret < 0)
846 			return ret;
847 	}
848 
849 	dev_info(dev, "using interrupt line INT2\n");
850 
851 	irq_open_drain = of_property_read_bool(np, "drive-open-drain");
852 
853 	data->dready_trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
854 						   indio_dev->name,
855 						   indio_dev->id);
856 	if (!data->dready_trig)
857 		return -ENOMEM;
858 
859 	irq_trig = irqd_get_trigger_type(irq_get_irq_data(data->irq));
860 
861 	if (irq_trig == IRQF_TRIGGER_RISING) {
862 		ret = regmap_field_write(data->regmap_fields[F_IPOL], 1);
863 		if (ret < 0)
864 			return ret;
865 	}
866 
867 	if (irq_open_drain)
868 		irq_trig |= IRQF_SHARED;
869 
870 	ret = devm_request_threaded_irq(dev, data->irq,
871 					fxas21002c_data_rdy_handler,
872 					fxas21002c_data_rdy_thread,
873 					irq_trig, "fxas21002c_data_ready",
874 					indio_dev);
875 	if (ret < 0)
876 		return ret;
877 
878 	data->dready_trig->dev.parent = dev;
879 	data->dready_trig->ops = &fxas21002c_trigger_ops;
880 	iio_trigger_set_drvdata(data->dready_trig, indio_dev);
881 
882 	return devm_iio_trigger_register(dev, data->dready_trig);
883 }
884 
885 static int fxas21002c_power_enable(struct fxas21002c_data *data)
886 {
887 	int ret;
888 
889 	ret = regulator_enable(data->vdd);
890 	if (ret < 0)
891 		return ret;
892 
893 	ret = regulator_enable(data->vddio);
894 	if (ret < 0) {
895 		regulator_disable(data->vdd);
896 		return ret;
897 	}
898 
899 	return 0;
900 }
901 
902 static void fxas21002c_power_disable(struct fxas21002c_data *data)
903 {
904 	regulator_disable(data->vdd);
905 	regulator_disable(data->vddio);
906 }
907 
908 static void fxas21002c_power_disable_action(void *_data)
909 {
910 	struct fxas21002c_data *data = _data;
911 
912 	fxas21002c_power_disable(data);
913 }
914 
915 static int fxas21002c_regulators_get(struct fxas21002c_data *data)
916 {
917 	struct device *dev = regmap_get_device(data->regmap);
918 
919 	data->vdd = devm_regulator_get(dev->parent, "vdd");
920 	if (IS_ERR(data->vdd))
921 		return PTR_ERR(data->vdd);
922 
923 	data->vddio = devm_regulator_get(dev->parent, "vddio");
924 
925 	return PTR_ERR_OR_ZERO(data->vddio);
926 }
927 
928 int fxas21002c_core_probe(struct device *dev, struct regmap *regmap, int irq,
929 			  const char *name)
930 {
931 	struct fxas21002c_data *data;
932 	struct iio_dev *indio_dev;
933 	struct regmap_field *f;
934 	int i;
935 	int ret;
936 
937 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
938 	if (!indio_dev)
939 		return -ENOMEM;
940 
941 	data = iio_priv(indio_dev);
942 	dev_set_drvdata(dev, indio_dev);
943 	data->irq = irq;
944 	data->regmap = regmap;
945 
946 	for (i = 0; i < F_MAX_FIELDS; i++) {
947 		f = devm_regmap_field_alloc(dev, data->regmap,
948 					    fxas21002c_reg_fields[i]);
949 		if (IS_ERR(f))
950 			return PTR_ERR(f);
951 
952 		data->regmap_fields[i] = f;
953 	}
954 
955 	mutex_init(&data->lock);
956 
957 	ret = fxas21002c_regulators_get(data);
958 	if (ret < 0)
959 		return ret;
960 
961 	ret = fxas21002c_power_enable(data);
962 	if (ret < 0)
963 		return ret;
964 
965 	ret = devm_add_action_or_reset(dev, fxas21002c_power_disable_action,
966 				       data);
967 	if (ret < 0)
968 		return ret;
969 
970 	ret = fxas21002c_chip_init(data);
971 	if (ret < 0)
972 		return ret;
973 
974 	indio_dev->channels = fxas21002c_channels;
975 	indio_dev->num_channels = ARRAY_SIZE(fxas21002c_channels);
976 	indio_dev->name = name;
977 	indio_dev->modes = INDIO_DIRECT_MODE;
978 	indio_dev->info = &fxas21002c_info;
979 
980 	ret = fxas21002c_trigger_probe(data);
981 	if (ret < 0)
982 		return ret;
983 
984 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
985 					      fxas21002c_trigger_handler, NULL);
986 	if (ret < 0)
987 		return ret;
988 
989 	ret = pm_runtime_set_active(dev);
990 	if (ret)
991 		return ret;
992 
993 	pm_runtime_enable(dev);
994 	pm_runtime_set_autosuspend_delay(dev, 2000);
995 	pm_runtime_use_autosuspend(dev);
996 
997 	ret = iio_device_register(indio_dev);
998 	if (ret < 0)
999 		goto pm_disable;
1000 
1001 	return 0;
1002 
1003 pm_disable:
1004 	pm_runtime_disable(dev);
1005 	pm_runtime_set_suspended(dev);
1006 	pm_runtime_put_noidle(dev);
1007 
1008 	return ret;
1009 }
1010 EXPORT_SYMBOL_GPL(fxas21002c_core_probe);
1011 
1012 void fxas21002c_core_remove(struct device *dev)
1013 {
1014 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1015 
1016 	iio_device_unregister(indio_dev);
1017 
1018 	pm_runtime_disable(dev);
1019 	pm_runtime_set_suspended(dev);
1020 	pm_runtime_put_noidle(dev);
1021 }
1022 EXPORT_SYMBOL_GPL(fxas21002c_core_remove);
1023 
1024 static int __maybe_unused fxas21002c_suspend(struct device *dev)
1025 {
1026 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1027 
1028 	fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
1029 	fxas21002c_power_disable(data);
1030 
1031 	return 0;
1032 }
1033 
1034 static int __maybe_unused fxas21002c_resume(struct device *dev)
1035 {
1036 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1037 	int ret;
1038 
1039 	ret = fxas21002c_power_enable(data);
1040 	if (ret < 0)
1041 		return ret;
1042 
1043 	return fxas21002c_mode_set(data, data->prev_mode);
1044 }
1045 
1046 static int __maybe_unused fxas21002c_runtime_suspend(struct device *dev)
1047 {
1048 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1049 
1050 	return fxas21002c_mode_set(data, FXAS21002C_MODE_READY);
1051 }
1052 
1053 static int __maybe_unused fxas21002c_runtime_resume(struct device *dev)
1054 {
1055 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1056 
1057 	return fxas21002c_mode_set(data, FXAS21002C_MODE_ACTIVE);
1058 }
1059 
1060 const struct dev_pm_ops fxas21002c_pm_ops = {
1061 	SET_SYSTEM_SLEEP_PM_OPS(fxas21002c_suspend, fxas21002c_resume)
1062 	SET_RUNTIME_PM_OPS(fxas21002c_runtime_suspend,
1063 			   fxas21002c_runtime_resume, NULL)
1064 };
1065 EXPORT_SYMBOL_GPL(fxas21002c_pm_ops);
1066 
1067 MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
1068 MODULE_LICENSE("GPL v2");
1069 MODULE_DESCRIPTION("FXAS21002C Gyro driver");
1070