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 		fxas21002c_pm_put(data);
403 		goto data_unlock;
404 	}
405 
406 	*val = sign_extend32(temp, 7);
407 
408 	ret = fxas21002c_pm_put(data);
409 	if (ret < 0)
410 		goto data_unlock;
411 
412 	ret = IIO_VAL_INT;
413 
414 data_unlock:
415 	mutex_unlock(&data->lock);
416 
417 	return ret;
418 }
419 
420 static int fxas21002c_axis_get(struct fxas21002c_data *data,
421 			       int index, int *val)
422 {
423 	struct device *dev = regmap_get_device(data->regmap);
424 	__be16 axis_be;
425 	int ret;
426 
427 	mutex_lock(&data->lock);
428 	ret = fxas21002c_pm_get(data);
429 	if (ret < 0)
430 		goto data_unlock;
431 
432 	ret = regmap_bulk_read(data->regmap, FXAS21002C_AXIS_TO_REG(index),
433 			       &axis_be, sizeof(axis_be));
434 	if (ret < 0) {
435 		dev_err(dev, "failed to read axis: %d: %d\n", index, ret);
436 		fxas21002c_pm_put(data);
437 		goto data_unlock;
438 	}
439 
440 	*val = sign_extend32(be16_to_cpu(axis_be), 15);
441 
442 	ret = fxas21002c_pm_put(data);
443 	if (ret < 0)
444 		goto data_unlock;
445 
446 	ret = IIO_VAL_INT;
447 
448 data_unlock:
449 	mutex_unlock(&data->lock);
450 
451 	return ret;
452 }
453 
454 static int fxas21002c_odr_get(struct fxas21002c_data *data, int *odr)
455 {
456 	unsigned int odr_bits;
457 	int ret;
458 
459 	mutex_lock(&data->lock);
460 	ret = regmap_field_read(data->regmap_fields[F_DR], &odr_bits);
461 	if (ret < 0)
462 		goto data_unlock;
463 
464 	*odr = fxas21002c_odr_hz_from_value(data, odr_bits);
465 
466 	ret = IIO_VAL_INT;
467 
468 data_unlock:
469 	mutex_unlock(&data->lock);
470 
471 	return ret;
472 }
473 
474 static int fxas21002c_odr_set(struct fxas21002c_data *data, int odr)
475 {
476 	int odr_bits;
477 
478 	odr_bits = fxas21002c_odr_value_from_hz(data, odr);
479 	if (odr_bits < 0)
480 		return odr_bits;
481 
482 	return fxas21002c_write(data, F_DR, odr_bits);
483 }
484 
485 static int fxas21002c_lpf_get(struct fxas21002c_data *data, int *val2)
486 {
487 	unsigned int bw_bits;
488 	int ret;
489 
490 	mutex_lock(&data->lock);
491 	ret = regmap_field_read(data->regmap_fields[F_BW], &bw_bits);
492 	if (ret < 0)
493 		goto data_unlock;
494 
495 	*val2 = fxas21002c_lpf_bw_from_value(data, bw_bits) * 10000;
496 
497 	ret = IIO_VAL_INT_PLUS_MICRO;
498 
499 data_unlock:
500 	mutex_unlock(&data->lock);
501 
502 	return ret;
503 }
504 
505 static int fxas21002c_lpf_set(struct fxas21002c_data *data, int bw)
506 {
507 	int bw_bits;
508 	int odr;
509 	int ret;
510 
511 	bw_bits = fxas21002c_lpf_value_from_bw(data, bw);
512 	if (bw_bits < 0)
513 		return bw_bits;
514 
515 	/*
516 	 * From table 33 of the device spec, for ODR = 25Hz and 12.5 value 0.08
517 	 * is not allowed and for ODR = 12.5 value 0.16 is also not allowed
518 	 */
519 	ret = fxas21002c_odr_get(data, &odr);
520 	if (ret < 0)
521 		return -EINVAL;
522 
523 	if ((odr == 25 && bw_bits > 0x01) || (odr == 12 && bw_bits > 0))
524 		return -EINVAL;
525 
526 	return fxas21002c_write(data, F_BW, bw_bits);
527 }
528 
529 static int fxas21002c_hpf_get(struct fxas21002c_data *data, int *val2)
530 {
531 	unsigned int sel_bits;
532 	int ret;
533 
534 	mutex_lock(&data->lock);
535 	ret = regmap_field_read(data->regmap_fields[F_SEL], &sel_bits);
536 	if (ret < 0)
537 		goto data_unlock;
538 
539 	*val2 = fxas21002c_hpf_sel_from_value(data, sel_bits);
540 
541 	ret = IIO_VAL_INT_PLUS_MICRO;
542 
543 data_unlock:
544 	mutex_unlock(&data->lock);
545 
546 	return ret;
547 }
548 
549 static int fxas21002c_hpf_set(struct fxas21002c_data *data, int sel)
550 {
551 	int sel_bits;
552 
553 	sel_bits = fxas21002c_hpf_value_from_sel(data, sel);
554 	if (sel_bits < 0)
555 		return sel_bits;
556 
557 	return fxas21002c_write(data, F_SEL, sel_bits);
558 }
559 
560 static int fxas21002c_scale_get(struct fxas21002c_data *data, int *val)
561 {
562 	int fs_bits;
563 	int scale;
564 	int ret;
565 
566 	mutex_lock(&data->lock);
567 	ret = regmap_field_read(data->regmap_fields[F_FS], &fs_bits);
568 	if (ret < 0)
569 		goto data_unlock;
570 
571 	scale = fxas21002c_range_fs_from_value(data, fs_bits);
572 	if (scale < 0) {
573 		ret = scale;
574 		goto data_unlock;
575 	}
576 
577 	*val = scale;
578 
579 data_unlock:
580 	mutex_unlock(&data->lock);
581 
582 	return ret;
583 }
584 
585 static int fxas21002c_scale_set(struct fxas21002c_data *data, int range)
586 {
587 	int fs_bits;
588 
589 	fs_bits = fxas21002c_range_value_from_fs(data, range);
590 	if (fs_bits < 0)
591 		return fs_bits;
592 
593 	return fxas21002c_write(data, F_FS, fs_bits);
594 }
595 
596 static int fxas21002c_read_raw(struct iio_dev *indio_dev,
597 			       struct iio_chan_spec const *chan, int *val,
598 			       int *val2, long mask)
599 {
600 	struct fxas21002c_data *data = iio_priv(indio_dev);
601 	int ret;
602 
603 	switch (mask) {
604 	case IIO_CHAN_INFO_RAW:
605 		switch (chan->type) {
606 		case IIO_TEMP:
607 			return fxas21002c_temp_get(data, val);
608 		case IIO_ANGL_VEL:
609 			return fxas21002c_axis_get(data, chan->scan_index, val);
610 		default:
611 			return -EINVAL;
612 		}
613 	case IIO_CHAN_INFO_SCALE:
614 		switch (chan->type) {
615 		case IIO_ANGL_VEL:
616 			*val2 = FXAS21002C_SCALE_FRACTIONAL;
617 			ret = fxas21002c_scale_get(data, val);
618 			if (ret < 0)
619 				return ret;
620 
621 			return IIO_VAL_FRACTIONAL;
622 		default:
623 			return -EINVAL;
624 		}
625 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
626 		*val = 0;
627 		return fxas21002c_lpf_get(data, val2);
628 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
629 		*val = 0;
630 		return fxas21002c_hpf_get(data, val2);
631 	case IIO_CHAN_INFO_SAMP_FREQ:
632 		*val2 = 0;
633 		return fxas21002c_odr_get(data, val);
634 	default:
635 		return -EINVAL;
636 	}
637 }
638 
639 static int fxas21002c_write_raw(struct iio_dev *indio_dev,
640 				struct iio_chan_spec const *chan, int val,
641 				int val2, long mask)
642 {
643 	struct fxas21002c_data *data = iio_priv(indio_dev);
644 	int range;
645 
646 	switch (mask) {
647 	case IIO_CHAN_INFO_SAMP_FREQ:
648 		if (val2)
649 			return -EINVAL;
650 
651 		return fxas21002c_odr_set(data, val);
652 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
653 		if (val)
654 			return -EINVAL;
655 
656 		val2 = val2 / 10000;
657 		return fxas21002c_lpf_set(data, val2);
658 	case IIO_CHAN_INFO_SCALE:
659 		switch (chan->type) {
660 		case IIO_ANGL_VEL:
661 			range = (((val * 1000 + val2 / 1000) *
662 				  FXAS21002C_SCALE_FRACTIONAL) / 1000);
663 			return fxas21002c_scale_set(data, range);
664 		default:
665 			return -EINVAL;
666 		}
667 	case IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY:
668 		return fxas21002c_hpf_set(data, val2);
669 	default:
670 		return -EINVAL;
671 	}
672 }
673 
674 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("12.5 25 50 100 200 400 800");
675 
676 static IIO_CONST_ATTR(in_anglvel_filter_low_pass_3db_frequency_available,
677 		      "0.32 0.16 0.08");
678 
679 static IIO_CONST_ATTR(in_anglvel_filter_high_pass_3db_frequency_available,
680 		      "0.018750 0.009625 0.004875 0.002475");
681 
682 static IIO_CONST_ATTR(in_anglvel_scale_available,
683 		      "125.0 62.5 31.25 15.625 7.8125");
684 
685 static struct attribute *fxas21002c_attributes[] = {
686 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
687 	&iio_const_attr_in_anglvel_filter_low_pass_3db_frequency_available.dev_attr.attr,
688 	&iio_const_attr_in_anglvel_filter_high_pass_3db_frequency_available.dev_attr.attr,
689 	&iio_const_attr_in_anglvel_scale_available.dev_attr.attr,
690 	NULL,
691 };
692 
693 static const struct attribute_group fxas21002c_attrs_group = {
694 	.attrs = fxas21002c_attributes,
695 };
696 
697 #define FXAS21002C_CHANNEL(_axis) {					\
698 	.type = IIO_ANGL_VEL,						\
699 	.modified = 1,							\
700 	.channel2 = IIO_MOD_##_axis,					\
701 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
702 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
703 		BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |	\
704 		BIT(IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY) |	\
705 		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
706 	.scan_index = CHANNEL_SCAN_INDEX_##_axis,			\
707 	.scan_type = {							\
708 		.sign = 's',						\
709 		.realbits = 16,						\
710 		.storagebits = 16,					\
711 		.endianness = IIO_BE,					\
712 	},								\
713 }
714 
715 static const struct iio_chan_spec fxas21002c_channels[] = {
716 	{
717 		.type = IIO_TEMP,
718 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
719 		.scan_index = -1,
720 	},
721 	FXAS21002C_CHANNEL(X),
722 	FXAS21002C_CHANNEL(Y),
723 	FXAS21002C_CHANNEL(Z),
724 };
725 
726 static const struct iio_info fxas21002c_info = {
727 	.attrs			= &fxas21002c_attrs_group,
728 	.read_raw		= &fxas21002c_read_raw,
729 	.write_raw		= &fxas21002c_write_raw,
730 };
731 
732 static irqreturn_t fxas21002c_trigger_handler(int irq, void *p)
733 {
734 	struct iio_poll_func *pf = p;
735 	struct iio_dev *indio_dev = pf->indio_dev;
736 	struct fxas21002c_data *data = iio_priv(indio_dev);
737 	int ret;
738 
739 	mutex_lock(&data->lock);
740 	ret = regmap_bulk_read(data->regmap, FXAS21002C_REG_OUT_X_MSB,
741 			       data->buffer, CHANNEL_SCAN_MAX * sizeof(s16));
742 	if (ret < 0)
743 		goto out_unlock;
744 
745 	iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
746 					   data->timestamp);
747 
748 out_unlock:
749 	mutex_unlock(&data->lock);
750 
751 	iio_trigger_notify_done(indio_dev->trig);
752 
753 	return IRQ_HANDLED;
754 }
755 
756 static int fxas21002c_chip_init(struct fxas21002c_data *data)
757 {
758 	struct device *dev = regmap_get_device(data->regmap);
759 	unsigned int chip_id;
760 	int ret;
761 
762 	ret = regmap_field_read(data->regmap_fields[F_WHO_AM_I], &chip_id);
763 	if (ret < 0)
764 		return ret;
765 
766 	if (chip_id != FXAS21002C_CHIP_ID_1 &&
767 	    chip_id != FXAS21002C_CHIP_ID_2) {
768 		dev_err(dev, "chip id 0x%02x is not supported\n", chip_id);
769 		return -EINVAL;
770 	}
771 
772 	data->chip_id = chip_id;
773 
774 	ret = fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
775 	if (ret < 0)
776 		return ret;
777 
778 	/* Set ODR to 200HZ as default */
779 	ret = fxas21002c_odr_set(data, 200);
780 	if (ret < 0)
781 		dev_err(dev, "failed to set ODR: %d\n", ret);
782 
783 	return ret;
784 }
785 
786 static int fxas21002c_data_rdy_trigger_set_state(struct iio_trigger *trig,
787 						 bool state)
788 {
789 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
790 	struct fxas21002c_data *data = iio_priv(indio_dev);
791 
792 	return regmap_field_write(data->regmap_fields[F_INT_EN_DRDY], state);
793 }
794 
795 static const struct iio_trigger_ops fxas21002c_trigger_ops = {
796 	.set_trigger_state = &fxas21002c_data_rdy_trigger_set_state,
797 };
798 
799 static irqreturn_t fxas21002c_data_rdy_handler(int irq, void *private)
800 {
801 	struct iio_dev *indio_dev = private;
802 	struct fxas21002c_data *data = iio_priv(indio_dev);
803 
804 	data->timestamp = iio_get_time_ns(indio_dev);
805 
806 	return IRQ_WAKE_THREAD;
807 }
808 
809 static irqreturn_t fxas21002c_data_rdy_thread(int irq, void *private)
810 {
811 	struct iio_dev *indio_dev = private;
812 	struct fxas21002c_data *data = iio_priv(indio_dev);
813 	unsigned int data_ready;
814 	int ret;
815 
816 	ret = regmap_field_read(data->regmap_fields[F_SRC_DRDY], &data_ready);
817 	if (ret < 0)
818 		return IRQ_NONE;
819 
820 	if (!data_ready)
821 		return IRQ_NONE;
822 
823 	iio_trigger_poll_chained(data->dready_trig);
824 
825 	return IRQ_HANDLED;
826 }
827 
828 static int fxas21002c_trigger_probe(struct fxas21002c_data *data)
829 {
830 	struct device *dev = regmap_get_device(data->regmap);
831 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
832 	struct device_node *np = indio_dev->dev.of_node;
833 	unsigned long irq_trig;
834 	bool irq_open_drain;
835 	int irq1;
836 	int ret;
837 
838 	if (!data->irq)
839 		return 0;
840 
841 	irq1 = of_irq_get_byname(np, "INT1");
842 
843 	if (irq1 == data->irq) {
844 		dev_info(dev, "using interrupt line INT1\n");
845 		ret = regmap_field_write(data->regmap_fields[F_INT_CFG_DRDY],
846 					 1);
847 		if (ret < 0)
848 			return ret;
849 	}
850 
851 	dev_info(dev, "using interrupt line INT2\n");
852 
853 	irq_open_drain = of_property_read_bool(np, "drive-open-drain");
854 
855 	data->dready_trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
856 						   indio_dev->name,
857 						   indio_dev->id);
858 	if (!data->dready_trig)
859 		return -ENOMEM;
860 
861 	irq_trig = irqd_get_trigger_type(irq_get_irq_data(data->irq));
862 
863 	if (irq_trig == IRQF_TRIGGER_RISING) {
864 		ret = regmap_field_write(data->regmap_fields[F_IPOL], 1);
865 		if (ret < 0)
866 			return ret;
867 	}
868 
869 	if (irq_open_drain)
870 		irq_trig |= IRQF_SHARED;
871 
872 	ret = devm_request_threaded_irq(dev, data->irq,
873 					fxas21002c_data_rdy_handler,
874 					fxas21002c_data_rdy_thread,
875 					irq_trig, "fxas21002c_data_ready",
876 					indio_dev);
877 	if (ret < 0)
878 		return ret;
879 
880 	data->dready_trig->ops = &fxas21002c_trigger_ops;
881 	iio_trigger_set_drvdata(data->dready_trig, indio_dev);
882 
883 	return devm_iio_trigger_register(dev, data->dready_trig);
884 }
885 
886 static int fxas21002c_power_enable(struct fxas21002c_data *data)
887 {
888 	int ret;
889 
890 	ret = regulator_enable(data->vdd);
891 	if (ret < 0)
892 		return ret;
893 
894 	ret = regulator_enable(data->vddio);
895 	if (ret < 0) {
896 		regulator_disable(data->vdd);
897 		return ret;
898 	}
899 
900 	return 0;
901 }
902 
903 static void fxas21002c_power_disable(struct fxas21002c_data *data)
904 {
905 	regulator_disable(data->vdd);
906 	regulator_disable(data->vddio);
907 }
908 
909 static void fxas21002c_power_disable_action(void *_data)
910 {
911 	struct fxas21002c_data *data = _data;
912 
913 	fxas21002c_power_disable(data);
914 }
915 
916 static int fxas21002c_regulators_get(struct fxas21002c_data *data)
917 {
918 	struct device *dev = regmap_get_device(data->regmap);
919 
920 	data->vdd = devm_regulator_get(dev->parent, "vdd");
921 	if (IS_ERR(data->vdd))
922 		return PTR_ERR(data->vdd);
923 
924 	data->vddio = devm_regulator_get(dev->parent, "vddio");
925 
926 	return PTR_ERR_OR_ZERO(data->vddio);
927 }
928 
929 int fxas21002c_core_probe(struct device *dev, struct regmap *regmap, int irq,
930 			  const char *name)
931 {
932 	struct fxas21002c_data *data;
933 	struct iio_dev *indio_dev;
934 	struct regmap_field *f;
935 	int i;
936 	int ret;
937 
938 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
939 	if (!indio_dev)
940 		return -ENOMEM;
941 
942 	data = iio_priv(indio_dev);
943 	dev_set_drvdata(dev, indio_dev);
944 	data->irq = irq;
945 	data->regmap = regmap;
946 
947 	for (i = 0; i < F_MAX_FIELDS; i++) {
948 		f = devm_regmap_field_alloc(dev, data->regmap,
949 					    fxas21002c_reg_fields[i]);
950 		if (IS_ERR(f))
951 			return PTR_ERR(f);
952 
953 		data->regmap_fields[i] = f;
954 	}
955 
956 	mutex_init(&data->lock);
957 
958 	ret = fxas21002c_regulators_get(data);
959 	if (ret < 0)
960 		return ret;
961 
962 	ret = fxas21002c_power_enable(data);
963 	if (ret < 0)
964 		return ret;
965 
966 	ret = devm_add_action_or_reset(dev, fxas21002c_power_disable_action,
967 				       data);
968 	if (ret < 0)
969 		return ret;
970 
971 	ret = fxas21002c_chip_init(data);
972 	if (ret < 0)
973 		return ret;
974 
975 	indio_dev->channels = fxas21002c_channels;
976 	indio_dev->num_channels = ARRAY_SIZE(fxas21002c_channels);
977 	indio_dev->name = name;
978 	indio_dev->modes = INDIO_DIRECT_MODE;
979 	indio_dev->info = &fxas21002c_info;
980 
981 	ret = fxas21002c_trigger_probe(data);
982 	if (ret < 0)
983 		return ret;
984 
985 	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
986 					      fxas21002c_trigger_handler, NULL);
987 	if (ret < 0)
988 		return ret;
989 
990 	ret = pm_runtime_set_active(dev);
991 	if (ret)
992 		return ret;
993 
994 	pm_runtime_enable(dev);
995 	pm_runtime_set_autosuspend_delay(dev, 2000);
996 	pm_runtime_use_autosuspend(dev);
997 
998 	ret = iio_device_register(indio_dev);
999 	if (ret < 0)
1000 		goto pm_disable;
1001 
1002 	return 0;
1003 
1004 pm_disable:
1005 	pm_runtime_disable(dev);
1006 	pm_runtime_set_suspended(dev);
1007 	pm_runtime_put_noidle(dev);
1008 
1009 	return ret;
1010 }
1011 EXPORT_SYMBOL_GPL(fxas21002c_core_probe);
1012 
1013 void fxas21002c_core_remove(struct device *dev)
1014 {
1015 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1016 
1017 	iio_device_unregister(indio_dev);
1018 
1019 	pm_runtime_disable(dev);
1020 	pm_runtime_set_suspended(dev);
1021 	pm_runtime_put_noidle(dev);
1022 }
1023 EXPORT_SYMBOL_GPL(fxas21002c_core_remove);
1024 
1025 static int __maybe_unused fxas21002c_suspend(struct device *dev)
1026 {
1027 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1028 
1029 	fxas21002c_mode_set(data, FXAS21002C_MODE_STANDBY);
1030 	fxas21002c_power_disable(data);
1031 
1032 	return 0;
1033 }
1034 
1035 static int __maybe_unused fxas21002c_resume(struct device *dev)
1036 {
1037 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1038 	int ret;
1039 
1040 	ret = fxas21002c_power_enable(data);
1041 	if (ret < 0)
1042 		return ret;
1043 
1044 	return fxas21002c_mode_set(data, data->prev_mode);
1045 }
1046 
1047 static int __maybe_unused fxas21002c_runtime_suspend(struct device *dev)
1048 {
1049 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1050 
1051 	return fxas21002c_mode_set(data, FXAS21002C_MODE_READY);
1052 }
1053 
1054 static int __maybe_unused fxas21002c_runtime_resume(struct device *dev)
1055 {
1056 	struct fxas21002c_data *data = iio_priv(dev_get_drvdata(dev));
1057 
1058 	return fxas21002c_mode_set(data, FXAS21002C_MODE_ACTIVE);
1059 }
1060 
1061 const struct dev_pm_ops fxas21002c_pm_ops = {
1062 	SET_SYSTEM_SLEEP_PM_OPS(fxas21002c_suspend, fxas21002c_resume)
1063 	SET_RUNTIME_PM_OPS(fxas21002c_runtime_suspend,
1064 			   fxas21002c_runtime_resume, NULL)
1065 };
1066 EXPORT_SYMBOL_GPL(fxas21002c_pm_ops);
1067 
1068 MODULE_AUTHOR("Rui Miguel Silva <rui.silva@linaro.org>");
1069 MODULE_LICENSE("GPL v2");
1070 MODULE_DESCRIPTION("FXAS21002C Gyro driver");
1071