summaryrefslogblamecommitdiff
path: root/drivers/iio/accel/adxl372.c
blob: d6e926de955e93e391a00cac67463fddd9036bcd (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525












































































































































































































































































































































































































































































































































                                                                            
// SPDX-License-Identifier: GPL-2.0+
/*
 * ADXL372 3-Axis Digital Accelerometer SPI driver
 *
 * Copyright 2018 Analog Devices Inc.
 */

#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/spi/spi.h>

#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

/* ADXL372 registers definition */
#define ADXL372_DEVID			0x00
#define ADXL372_DEVID_MST		0x01
#define ADXL372_PARTID			0x02
#define ADXL372_REVID			0x03
#define ADXL372_STATUS_1		0x04
#define ADXL372_STATUS_2		0x05
#define ADXL372_FIFO_ENTRIES_2		0x06
#define ADXL372_FIFO_ENTRIES_1		0x07
#define ADXL372_X_DATA_H		0x08
#define ADXL372_X_DATA_L		0x09
#define ADXL372_Y_DATA_H		0x0A
#define ADXL372_Y_DATA_L		0x0B
#define ADXL372_Z_DATA_H		0x0C
#define ADXL372_Z_DATA_L		0x0D
#define ADXL372_X_MAXPEAK_H		0x15
#define ADXL372_X_MAXPEAK_L		0x16
#define ADXL372_Y_MAXPEAK_H		0x17
#define ADXL372_Y_MAXPEAK_L		0x18
#define ADXL372_Z_MAXPEAK_H		0x19
#define ADXL372_Z_MAXPEAK_L		0x1A
#define ADXL372_OFFSET_X		0x20
#define ADXL372_OFFSET_Y		0x21
#define ADXL372_OFFSET_Z		0x22
#define ADXL372_X_THRESH_ACT_H		0x23
#define ADXL372_X_THRESH_ACT_L		0x24
#define ADXL372_Y_THRESH_ACT_H		0x25
#define ADXL372_Y_THRESH_ACT_L		0x26
#define ADXL372_Z_THRESH_ACT_H		0x27
#define ADXL372_Z_THRESH_ACT_L		0x28
#define ADXL372_TIME_ACT		0x29
#define ADXL372_X_THRESH_INACT_H	0x2A
#define ADXL372_X_THRESH_INACT_L	0x2B
#define ADXL372_Y_THRESH_INACT_H	0x2C
#define ADXL372_Y_THRESH_INACT_L	0x2D
#define ADXL372_Z_THRESH_INACT_H	0x2E
#define ADXL372_Z_THRESH_INACT_L	0x2F
#define ADXL372_TIME_INACT_H		0x30
#define ADXL372_TIME_INACT_L		0x31
#define ADXL372_X_THRESH_ACT2_H		0x32
#define ADXL372_X_THRESH_ACT2_L		0x33
#define ADXL372_Y_THRESH_ACT2_H		0x34
#define ADXL372_Y_THRESH_ACT2_L		0x35
#define ADXL372_Z_THRESH_ACT2_H		0x36
#define ADXL372_Z_THRESH_ACT2_L		0x37
#define ADXL372_HPF			0x38
#define ADXL372_FIFO_SAMPLES		0x39
#define ADXL372_FIFO_CTL		0x3A
#define ADXL372_INT1_MAP		0x3B
#define ADXL372_INT2_MAP		0x3C
#define ADXL372_TIMING			0x3D
#define ADXL372_MEASURE			0x3E
#define ADXL372_POWER_CTL		0x3F
#define ADXL372_SELF_TEST		0x40
#define ADXL372_RESET			0x41
#define ADXL372_FIFO_DATA		0x42

#define ADXL372_DEVID_VAL		0xAD
#define ADXL372_PARTID_VAL		0xFA
#define ADXL372_RESET_CODE		0x52

/* ADXL372_POWER_CTL */
#define ADXL372_POWER_CTL_MODE_MSK		GENMASK_ULL(1, 0)
#define ADXL372_POWER_CTL_MODE(x)		(((x) & 0x3) << 0)

/* ADXL372_MEASURE */
#define ADXL372_MEASURE_LINKLOOP_MSK		GENMASK_ULL(5, 4)
#define ADXL372_MEASURE_LINKLOOP_MODE(x)	(((x) & 0x3) << 4)
#define ADXL372_MEASURE_BANDWIDTH_MSK		GENMASK_ULL(2, 0)
#define ADXL372_MEASURE_BANDWIDTH_MODE(x)	(((x) & 0x7) << 0)

/* ADXL372_TIMING */
#define ADXL372_TIMING_ODR_MSK			GENMASK_ULL(7, 5)
#define ADXL372_TIMING_ODR_MODE(x)		(((x) & 0x7) << 5)

/* ADXL372_FIFO_CTL */
#define ADXL372_FIFO_CTL_FORMAT_MSK		GENMASK(5, 3)
#define ADXL372_FIFO_CTL_FORMAT_MODE(x)		(((x) & 0x7) << 3)
#define ADXL372_FIFO_CTL_MODE_MSK		GENMASK(2, 1)
#define ADXL372_FIFO_CTL_MODE_MODE(x)		(((x) & 0x3) << 1)
#define ADXL372_FIFO_CTL_SAMPLES_MSK		BIT(1)
#define ADXL372_FIFO_CTL_SAMPLES_MODE(x)	(((x) > 0xFF) ? 1 : 0)

/* ADXL372_STATUS_1 */
#define ADXL372_STATUS_1_DATA_RDY(x)		(((x) >> 0) & 0x1)
#define ADXL372_STATUS_1_FIFO_RDY(x)		(((x) >> 1) & 0x1)
#define ADXL372_STATUS_1_FIFO_FULL(x)		(((x) >> 2) & 0x1)
#define ADXL372_STATUS_1_FIFO_OVR(x)		(((x) >> 3) & 0x1)
#define ADXL372_STATUS_1_USR_NVM_BUSY(x)	(((x) >> 5) & 0x1)
#define ADXL372_STATUS_1_AWAKE(x)		(((x) >> 6) & 0x1)
#define ADXL372_STATUS_1_ERR_USR_REGS(x)	(((x) >> 7) & 0x1)

/* ADXL372_INT1_MAP */
#define ADXL372_INT1_MAP_DATA_RDY_MSK		BIT(0)
#define ADXL372_INT1_MAP_DATA_RDY_MODE(x)	(((x) & 0x1) << 0)
#define ADXL372_INT1_MAP_FIFO_RDY_MSK		BIT(1)
#define ADXL372_INT1_MAP_FIFO_RDY_MODE(x)	(((x) & 0x1) << 1)
#define ADXL372_INT1_MAP_FIFO_FULL_MSK		BIT(2)
#define ADXL372_INT1_MAP_FIFO_FULL_MODE(x)	(((x) & 0x1) << 2)
#define ADXL372_INT1_MAP_FIFO_OVR_MSK		BIT(3)
#define ADXL372_INT1_MAP_FIFO_OVR_MODE(x)	(((x) & 0x1) << 3)
#define ADXL372_INT1_MAP_INACT_MSK		BIT(4)
#define ADXL372_INT1_MAP_INACT_MODE(x)		(((x) & 0x1) << 4)
#define ADXL372_INT1_MAP_ACT_MSK		BIT(5)
#define ADXL372_INT1_MAP_ACT_MODE(x)		(((x) & 0x1) << 5)
#define ADXL372_INT1_MAP_AWAKE_MSK		BIT(6)
#define ADXL372_INT1_MAP_AWAKE_MODE(x)		(((x) & 0x1) << 6)
#define ADXL372_INT1_MAP_LOW_MSK		BIT(7)
#define ADXL372_INT1_MAP_LOW_MODE(x)		(((x) & 0x1) << 7)

/*
 * At +/- 200g with 12-bit resolution, scale is computed as:
 * (200 + 200) * 9.81 / (2^12 - 1) = 0.958241
 */
#define ADXL372_USCALE	958241

enum adxl372_op_mode {
	ADXL372_STANDBY,
	ADXL372_WAKE_UP,
	ADXL372_INSTANT_ON,
	ADXL372_FULL_BW_MEASUREMENT,
};

enum adxl372_act_proc_mode {
	ADXL372_DEFAULT,
	ADXL372_LINKED,
	ADXL372_LOOPED,
};

enum adxl372_th_activity {
	ADXL372_ACTIVITY,
	ADXL372_ACTIVITY2,
	ADXL372_INACTIVITY,
};

enum adxl372_odr {
	ADXL372_ODR_400HZ,
	ADXL372_ODR_800HZ,
	ADXL372_ODR_1600HZ,
	ADXL372_ODR_3200HZ,
	ADXL372_ODR_6400HZ,
};

enum adxl372_bandwidth {
	ADXL372_BW_200HZ,
	ADXL372_BW_400HZ,
	ADXL372_BW_800HZ,
	ADXL372_BW_1600HZ,
	ADXL372_BW_3200HZ,
};

static const unsigned int adxl372_th_reg_high_addr[3] = {
	[ADXL372_ACTIVITY] = ADXL372_X_THRESH_ACT_H,
	[ADXL372_ACTIVITY2] = ADXL372_X_THRESH_ACT2_H,
	[ADXL372_INACTIVITY] = ADXL372_X_THRESH_INACT_H,
};

#define ADXL372_ACCEL_CHANNEL(index, reg, axis) {			\
	.type = IIO_ACCEL,						\
	.address = reg,							\
	.modified = 1,							\
	.channel2 = IIO_MOD_##axis,					\
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),			\
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),		\
}

static const struct iio_chan_spec adxl372_channels[] = {
	ADXL372_ACCEL_CHANNEL(0, ADXL372_X_DATA_H, X),
	ADXL372_ACCEL_CHANNEL(1, ADXL372_Y_DATA_H, Y),
	ADXL372_ACCEL_CHANNEL(2, ADXL372_Z_DATA_H, Z),
};

struct adxl372_state {
	struct spi_device		*spi;
	struct regmap			*regmap;
	enum adxl372_op_mode		op_mode;
	enum adxl372_act_proc_mode	act_proc_mode;
	enum adxl372_odr		odr;
	enum adxl372_bandwidth		bw;
	u32				act_time_ms;
	u32				inact_time_ms;
};

static int adxl372_read_axis(struct adxl372_state *st, u8 addr)
{
	__be16 regval;
	int ret;

	ret = regmap_bulk_read(st->regmap, addr, &regval, sizeof(regval));
	if (ret < 0)
		return ret;

	return be16_to_cpu(regval);
}

static int adxl372_set_op_mode(struct adxl372_state *st,
			       enum adxl372_op_mode op_mode)
{
	int ret;

	ret = regmap_update_bits(st->regmap, ADXL372_POWER_CTL,
				 ADXL372_POWER_CTL_MODE_MSK,
				 ADXL372_POWER_CTL_MODE(op_mode));
	if (ret < 0)
		return ret;

	st->op_mode = op_mode;

	return ret;
}

static int adxl372_set_odr(struct adxl372_state *st,
			   enum adxl372_odr odr)
{
	int ret;

	ret = regmap_update_bits(st->regmap, ADXL372_TIMING,
				 ADXL372_TIMING_ODR_MSK,
				 ADXL372_TIMING_ODR_MODE(odr));
	if (ret < 0)
		return ret;

	st->odr = odr;

	return ret;
}

static int adxl372_set_bandwidth(struct adxl372_state *st,
				 enum adxl372_bandwidth bw)
{
	int ret;

	ret = regmap_update_bits(st->regmap, ADXL372_MEASURE,
				 ADXL372_MEASURE_BANDWIDTH_MSK,
				 ADXL372_MEASURE_BANDWIDTH_MODE(bw));
	if (ret < 0)
		return ret;

	st->bw = bw;

	return ret;
}

static int adxl372_set_act_proc_mode(struct adxl372_state *st,
				     enum adxl372_act_proc_mode mode)
{
	int ret;

	ret = regmap_update_bits(st->regmap,
				 ADXL372_MEASURE,
				 ADXL372_MEASURE_LINKLOOP_MSK,
				 ADXL372_MEASURE_LINKLOOP_MODE(mode));
	if (ret < 0)
		return ret;

	st->act_proc_mode = mode;

	return ret;
}

static int adxl372_set_activity_threshold(struct adxl372_state *st,
					  enum adxl372_th_activity act,
					  bool ref_en, bool enable,
					  unsigned int threshold)
{
	unsigned char buf[6];
	unsigned char th_reg_high_val, th_reg_low_val, th_reg_high_addr;

	/* scale factor is 100 mg/code */
	th_reg_high_val = (threshold / 100) >> 3;
	th_reg_low_val = ((threshold / 100) << 5) | (ref_en << 1) | enable;
	th_reg_high_addr = adxl372_th_reg_high_addr[act];

	buf[0] = th_reg_high_val;
	buf[1] = th_reg_low_val;
	buf[2] = th_reg_high_val;
	buf[3] = th_reg_low_val;
	buf[4] = th_reg_high_val;
	buf[5] = th_reg_low_val;

	return regmap_bulk_write(st->regmap, th_reg_high_addr,
				 buf, ARRAY_SIZE(buf));
}

static int adxl372_set_activity_time_ms(struct adxl372_state *st,
					unsigned int act_time_ms)
{
	unsigned int reg_val, scale_factor;
	int ret;

	/*
	 * 3.3 ms per code is the scale factor of the TIME_ACT register for
	 * ODR = 6400 Hz. It is 6.6 ms per code for ODR = 3200 Hz and below.
	 */
	if (st->odr == ADXL372_ODR_6400HZ)
		scale_factor = 3300;
	else
		scale_factor = 6600;

	reg_val = DIV_ROUND_CLOSEST(act_time_ms * 1000, scale_factor);

	/* TIME_ACT register is 8 bits wide */
	if (reg_val > 0xFF)
		reg_val = 0xFF;

	ret = regmap_write(st->regmap, ADXL372_TIME_ACT, reg_val);
	if (ret < 0)
		return ret;

	st->act_time_ms = act_time_ms;

	return ret;
}

static int adxl372_set_inactivity_time_ms(struct adxl372_state *st,
					  unsigned int inact_time_ms)
{
	unsigned int reg_val_h, reg_val_l, res, scale_factor;
	int ret;

	/*
	 * 13 ms per code is the scale factor of the TIME_INACT register for
	 * ODR = 6400 Hz. It is 26 ms per code for ODR = 3200 Hz and below.
	 */
	if (st->odr == ADXL372_ODR_6400HZ)
		scale_factor = 13;
	else
		scale_factor = 26;

	res = DIV_ROUND_CLOSEST(inact_time_ms, scale_factor);
	reg_val_h = (res >> 8) & 0xFF;
	reg_val_l = res & 0xFF;

	ret = regmap_write(st->regmap, ADXL372_TIME_INACT_H, reg_val_h);
	if (ret < 0)
		return ret;

	ret = regmap_write(st->regmap, ADXL372_TIME_INACT_L, reg_val_l);
	if (ret < 0)
		return ret;

	st->inact_time_ms = inact_time_ms;

	return ret;
}

static int adxl372_setup(struct adxl372_state *st)
{
	unsigned int regval;
	int ret;

	ret = regmap_read(st->regmap, ADXL372_DEVID, &regval);
	if (ret < 0)
		return ret;

	if (regval != ADXL372_DEVID_VAL) {
		dev_err(&st->spi->dev, "Invalid chip id %x\n", regval);
		return -ENODEV;
	}

	ret = adxl372_set_op_mode(st, ADXL372_STANDBY);
	if (ret < 0)
		return ret;

	/* Set threshold for activity detection to 1g */
	ret = adxl372_set_activity_threshold(st, ADXL372_ACTIVITY,
					     true, true, 1000);
	if (ret < 0)
		return ret;

	/* Set threshold for inactivity detection to 100mg */
	ret = adxl372_set_activity_threshold(st, ADXL372_INACTIVITY,
					     true, true, 100);
	if (ret < 0)
		return ret;

	/* Set activity processing in Looped mode */
	ret = adxl372_set_act_proc_mode(st, ADXL372_LOOPED);
	if (ret < 0)
		return ret;

	ret = adxl372_set_odr(st, ADXL372_ODR_6400HZ);
	if (ret < 0)
		return ret;

	ret = adxl372_set_bandwidth(st, ADXL372_BW_3200HZ);
	if (ret < 0)
		return ret;

	/* Set activity timer to 1ms */
	ret = adxl372_set_activity_time_ms(st, 1);
	if (ret < 0)
		return ret;

	/* Set inactivity timer to 10s */
	ret = adxl372_set_inactivity_time_ms(st, 10000);
	if (ret < 0)
		return ret;

	/* Set the mode of operation to full bandwidth measurement mode */
	return adxl372_set_op_mode(st, ADXL372_FULL_BW_MEASUREMENT);
}

static int adxl372_reg_access(struct iio_dev *indio_dev,
			      unsigned int reg,
			      unsigned int writeval,
			      unsigned int *readval)
{
	struct adxl372_state *st = iio_priv(indio_dev);

	if (readval)
		return regmap_read(st->regmap, reg, readval);
	else
		return regmap_write(st->regmap, reg, writeval);
}

static int adxl372_read_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int *val, int *val2, long info)
{
	struct adxl372_state *st = iio_priv(indio_dev);
	int ret;

	switch (info) {
	case IIO_CHAN_INFO_RAW:
		ret = adxl372_read_axis(st, chan->address);
		if (ret < 0)
			return ret;

		*val = sign_extend32(ret >> chan->scan_type.shift,
				     chan->scan_type.realbits - 1);
		return IIO_VAL_INT;
	case IIO_CHAN_INFO_SCALE:
		*val = 0;
		*val2 = ADXL372_USCALE;
		return IIO_VAL_INT_PLUS_MICRO;
	default:
		return -EINVAL;
	}
}

static const struct iio_info adxl372_info = {
	.read_raw = adxl372_read_raw,
	.debugfs_reg_access = &adxl372_reg_access,
};

static const struct regmap_config adxl372_spi_regmap_config = {
	.reg_bits = 7,
	.pad_bits = 1,
	.val_bits = 8,
	.read_flag_mask = BIT(0),
};

static int adxl372_probe(struct spi_device *spi)
{
	struct iio_dev *indio_dev;
	struct adxl372_state *st;
	struct regmap *regmap;
	int ret;

	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
	if (!indio_dev)
		return -ENOMEM;

	st = iio_priv(indio_dev);
	spi_set_drvdata(spi, indio_dev);

	st->spi = spi;

	regmap = devm_regmap_init_spi(spi, &adxl372_spi_regmap_config);
	if (IS_ERR(regmap))
		return PTR_ERR(regmap);

	st->regmap = regmap;

	indio_dev->channels = adxl372_channels;
	indio_dev->num_channels = ARRAY_SIZE(adxl372_channels);
	indio_dev->dev.parent = &spi->dev;
	indio_dev->name = spi_get_device_id(spi)->name;
	indio_dev->info = &adxl372_info;
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = adxl372_setup(st);
	if (ret < 0) {
		dev_err(&st->spi->dev, "ADXL372 setup failed\n");
		return ret;
	}

	return devm_iio_device_register(&st->spi->dev, indio_dev);
}

static const struct spi_device_id adxl372_id[] = {
	{ "adxl372", 0 },
	{}
};
MODULE_DEVICE_TABLE(spi, adxl372_id);

static struct spi_driver adxl372_driver = {
	.driver = {
		.name = KBUILD_MODNAME,
	},
	.probe = adxl372_probe,
	.id_table = adxl372_id,
};

module_spi_driver(adxl372_driver);

MODULE_AUTHOR("Stefan Popa <stefan.popa@analog.com>");
MODULE_DESCRIPTION("Analog Devices ADXL372 3-axis accelerometer driver");
MODULE_LICENSE("GPL");