1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for the TI TMAG5273 Low-Power Linear 3D Hall-Effect Sensor
4 *
5 * Copyright (C) 2022 WolfVision GmbH
6 *
7 * Author: Gerald Loacker <gerald.loacker@wolfvision.net>
8 */
9
10#include <linux/bitfield.h>
11#include <linux/bits.h>
12#include <linux/delay.h>
13#include <linux/module.h>
14#include <linux/i2c.h>
15#include <linux/regmap.h>
16#include <linux/pm_runtime.h>
17
18#include <linux/iio/iio.h>
19#include <linux/iio/sysfs.h>
20
21#define TMAG5273_DEVICE_CONFIG_1	 0x00
22#define TMAG5273_DEVICE_CONFIG_2	 0x01
23#define TMAG5273_SENSOR_CONFIG_1	 0x02
24#define TMAG5273_SENSOR_CONFIG_2	 0x03
25#define TMAG5273_X_THR_CONFIG		 0x04
26#define TMAG5273_Y_THR_CONFIG		 0x05
27#define TMAG5273_Z_THR_CONFIG		 0x06
28#define TMAG5273_T_CONFIG		 0x07
29#define TMAG5273_INT_CONFIG_1		 0x08
30#define TMAG5273_MAG_GAIN_CONFIG	 0x09
31#define TMAG5273_MAG_OFFSET_CONFIG_1	 0x0A
32#define TMAG5273_MAG_OFFSET_CONFIG_2	 0x0B
33#define TMAG5273_I2C_ADDRESS		 0x0C
34#define TMAG5273_DEVICE_ID		 0x0D
35#define TMAG5273_MANUFACTURER_ID_LSB	 0x0E
36#define TMAG5273_MANUFACTURER_ID_MSB	 0x0F
37#define TMAG5273_T_MSB_RESULT		 0x10
38#define TMAG5273_T_LSB_RESULT		 0x11
39#define TMAG5273_X_MSB_RESULT		 0x12
40#define TMAG5273_X_LSB_RESULT		 0x13
41#define TMAG5273_Y_MSB_RESULT		 0x14
42#define TMAG5273_Y_LSB_RESULT		 0x15
43#define TMAG5273_Z_MSB_RESULT		 0x16
44#define TMAG5273_Z_LSB_RESULT		 0x17
45#define TMAG5273_CONV_STATUS		 0x18
46#define TMAG5273_ANGLE_RESULT_MSB	 0x19
47#define TMAG5273_ANGLE_RESULT_LSB	 0x1A
48#define TMAG5273_MAGNITUDE_RESULT	 0x1B
49#define TMAG5273_DEVICE_STATUS		 0x1C
50#define TMAG5273_MAX_REG		 TMAG5273_DEVICE_STATUS
51
52#define TMAG5273_AUTOSLEEP_DELAY_MS	 5000
53#define TMAG5273_MAX_AVERAGE             32
54
55/*
56 * bits in the TMAG5273_MANUFACTURER_ID_LSB / MSB register
57 * 16-bit unique manufacturer ID 0x49 / 0x54 = "TI"
58 */
59#define TMAG5273_MANUFACTURER_ID	 0x5449
60
61/* bits in the TMAG5273_DEVICE_CONFIG_1 register */
62#define TMAG5273_AVG_MODE_MASK		 GENMASK(4, 2)
63#define TMAG5273_AVG_1_MODE		 FIELD_PREP(TMAG5273_AVG_MODE_MASK, 0)
64#define TMAG5273_AVG_2_MODE		 FIELD_PREP(TMAG5273_AVG_MODE_MASK, 1)
65#define TMAG5273_AVG_4_MODE		 FIELD_PREP(TMAG5273_AVG_MODE_MASK, 2)
66#define TMAG5273_AVG_8_MODE		 FIELD_PREP(TMAG5273_AVG_MODE_MASK, 3)
67#define TMAG5273_AVG_16_MODE		 FIELD_PREP(TMAG5273_AVG_MODE_MASK, 4)
68#define TMAG5273_AVG_32_MODE		 FIELD_PREP(TMAG5273_AVG_MODE_MASK, 5)
69
70/* bits in the TMAG5273_DEVICE_CONFIG_2 register */
71#define TMAG5273_OP_MODE_MASK		 GENMASK(1, 0)
72#define TMAG5273_OP_MODE_STANDBY	 FIELD_PREP(TMAG5273_OP_MODE_MASK, 0)
73#define TMAG5273_OP_MODE_SLEEP		 FIELD_PREP(TMAG5273_OP_MODE_MASK, 1)
74#define TMAG5273_OP_MODE_CONT		 FIELD_PREP(TMAG5273_OP_MODE_MASK, 2)
75#define TMAG5273_OP_MODE_WAKEUP		 FIELD_PREP(TMAG5273_OP_MODE_MASK, 3)
76
77/* bits in the TMAG5273_SENSOR_CONFIG_1 register */
78#define TMAG5273_MAG_CH_EN_MASK		 GENMASK(7, 4)
79#define TMAG5273_MAG_CH_EN_X_Y_Z	 7
80
81/* bits in the TMAG5273_SENSOR_CONFIG_2 register */
82#define TMAG5273_Z_RANGE_MASK		 BIT(0)
83#define TMAG5273_X_Y_RANGE_MASK		 BIT(1)
84#define TMAG5273_ANGLE_EN_MASK		 GENMASK(3, 2)
85#define TMAG5273_ANGLE_EN_OFF		 0
86#define TMAG5273_ANGLE_EN_X_Y		 1
87#define TMAG5273_ANGLE_EN_Y_Z		 2
88#define TMAG5273_ANGLE_EN_X_Z		 3
89
90/* bits in the TMAG5273_T_CONFIG register */
91#define TMAG5273_T_CH_EN		 BIT(0)
92
93/* bits in the TMAG5273_DEVICE_ID register */
94#define TMAG5273_VERSION_MASK		 GENMASK(1, 0)
95
96/* bits in the TMAG5273_CONV_STATUS register */
97#define TMAG5273_CONV_STATUS_COMPLETE	 BIT(0)
98
99enum tmag5273_channels {
100	TEMPERATURE = 0,
101	AXIS_X,
102	AXIS_Y,
103	AXIS_Z,
104	ANGLE,
105	MAGNITUDE,
106};
107
108enum tmag5273_scale_index {
109	MAGN_RANGE_LOW = 0,
110	MAGN_RANGE_HIGH,
111	MAGN_RANGE_NUM
112};
113
114/* state container for the TMAG5273 driver */
115struct tmag5273_data {
116	struct device *dev;
117	unsigned int devid;
118	unsigned int version;
119	char name[16];
120	unsigned int conv_avg;
121	unsigned int scale;
122	enum tmag5273_scale_index scale_index;
123	unsigned int angle_measurement;
124	struct regmap *map;
125	struct regulator *vcc;
126
127	/*
128	 * Locks the sensor for exclusive use during a measurement (which
129	 * involves several register transactions so the regmap lock is not
130	 * enough) so that measurements get serialized in a
131	 * first-come-first-serve manner.
132	 */
133	struct mutex lock;
134};
135
136static const char *const tmag5273_angle_names[] = { "off", "x-y", "y-z", "x-z" };
137
138/*
139 * Averaging enables additional sampling of the sensor data to reduce the noise
140 * effect, but also increases conversion time.
141 */
142static const unsigned int tmag5273_avg_table[] = {
143	1, 2, 4, 8, 16, 32,
144};
145
146/*
147 * Magnetic resolution in Gauss for different TMAG5273 versions.
148 * Scale[Gauss] = Range[mT] * 1000 / 2^15 * 10, (1 mT = 10 Gauss)
149 * Only version 1 and 2 are valid, version 0 and 3 are reserved.
150 */
151static const struct iio_val_int_plus_micro tmag5273_scale[][MAGN_RANGE_NUM] = {
152	{ { 0,     0 }, { 0,     0 } },
153	{ { 0, 12200 }, { 0, 24400 } },
154	{ { 0, 40600 }, { 0, 81200 } },
155	{ { 0,     0 }, { 0,     0 } },
156};
157
158static int tmag5273_get_measure(struct tmag5273_data *data, s16 *t, s16 *x,
159				s16 *y, s16 *z, u16 *angle, u16 *magnitude)
160{
161	unsigned int status, val;
162	__be16 reg_data[4];
163	int ret;
164
165	mutex_lock(&data->lock);
166
167	/*
168	 * Max. conversion time is 2425 us in 32x averaging mode for all three
169	 * channels. Since we are in continuous measurement mode, a measurement
170	 * may already be there, so poll for completed measurement with
171	 * timeout.
172	 */
173	ret = regmap_read_poll_timeout(data->map, TMAG5273_CONV_STATUS, status,
174				       status & TMAG5273_CONV_STATUS_COMPLETE,
175				       100, 10000);
176	if (ret) {
177		dev_err(data->dev, "timeout waiting for measurement\n");
178		goto out_unlock;
179	}
180
181	ret = regmap_bulk_read(data->map, TMAG5273_T_MSB_RESULT, reg_data,
182			       sizeof(reg_data));
183	if (ret)
184		goto out_unlock;
185	*t = be16_to_cpu(reg_data[0]);
186	*x = be16_to_cpu(reg_data[1]);
187	*y = be16_to_cpu(reg_data[2]);
188	*z = be16_to_cpu(reg_data[3]);
189
190	ret = regmap_bulk_read(data->map, TMAG5273_ANGLE_RESULT_MSB,
191			       &reg_data[0], sizeof(reg_data[0]));
192	if (ret)
193		goto out_unlock;
194	/*
195	 * angle has 9 bits integer value and 4 bits fractional part
196	 * 15 14 13 12 11 10 9  8  7  6  5  4  3  2  1  0
197	 * 0  0  0  a  a  a  a  a  a  a  a  a  f  f  f  f
198	 */
199	*angle = be16_to_cpu(reg_data[0]);
200
201	ret = regmap_read(data->map, TMAG5273_MAGNITUDE_RESULT, &val);
202	if (ret < 0)
203		goto out_unlock;
204	*magnitude = val;
205
206out_unlock:
207	mutex_unlock(&data->lock);
208	return ret;
209}
210
211static int tmag5273_write_osr(struct tmag5273_data *data, int val)
212{
213	int i;
214
215	if (val == data->conv_avg)
216		return 0;
217
218	for (i = 0; i < ARRAY_SIZE(tmag5273_avg_table); i++) {
219		if (tmag5273_avg_table[i] == val)
220			break;
221	}
222	if (i == ARRAY_SIZE(tmag5273_avg_table))
223		return -EINVAL;
224	data->conv_avg = val;
225
226	return regmap_update_bits(data->map, TMAG5273_DEVICE_CONFIG_1,
227				  TMAG5273_AVG_MODE_MASK,
228				  FIELD_PREP(TMAG5273_AVG_MODE_MASK, i));
229}
230
231static int tmag5273_write_scale(struct tmag5273_data *data, int scale_micro)
232{
233	u32 value;
234	int i;
235
236	for (i = 0; i < ARRAY_SIZE(tmag5273_scale[0]); i++) {
237		if (tmag5273_scale[data->version][i].micro == scale_micro)
238			break;
239	}
240	if (i == ARRAY_SIZE(tmag5273_scale[0]))
241		return -EINVAL;
242	data->scale_index = i;
243
244	if (data->scale_index == MAGN_RANGE_LOW)
245		value = 0;
246	else
247		value = TMAG5273_Z_RANGE_MASK | TMAG5273_X_Y_RANGE_MASK;
248
249	return regmap_update_bits(data->map, TMAG5273_SENSOR_CONFIG_2,
250				  TMAG5273_Z_RANGE_MASK | TMAG5273_X_Y_RANGE_MASK, value);
251}
252
253static int tmag5273_read_avail(struct iio_dev *indio_dev,
254			       struct iio_chan_spec const *chan,
255			       const int **vals, int *type, int *length,
256			       long mask)
257{
258	struct tmag5273_data *data = iio_priv(indio_dev);
259
260	switch (mask) {
261	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
262		*vals = tmag5273_avg_table;
263		*type = IIO_VAL_INT;
264		*length = ARRAY_SIZE(tmag5273_avg_table);
265		return IIO_AVAIL_LIST;
266	case IIO_CHAN_INFO_SCALE:
267		switch (chan->type) {
268		case IIO_MAGN:
269			*type = IIO_VAL_INT_PLUS_MICRO;
270			*vals = (int *)tmag5273_scale[data->version];
271			*length = ARRAY_SIZE(tmag5273_scale[data->version]) *
272				  MAGN_RANGE_NUM;
273			return IIO_AVAIL_LIST;
274		default:
275			return -EINVAL;
276		}
277	default:
278		return -EINVAL;
279	}
280}
281
282static int tmag5273_read_raw(struct iio_dev *indio_dev,
283			     const struct iio_chan_spec *chan, int *val,
284			     int *val2, long mask)
285{
286	struct tmag5273_data *data = iio_priv(indio_dev);
287	s16 t, x, y, z;
288	u16 angle, magnitude;
289	int ret;
290
291	switch (mask) {
292	case IIO_CHAN_INFO_PROCESSED:
293	case IIO_CHAN_INFO_RAW:
294		ret = pm_runtime_resume_and_get(data->dev);
295		if (ret < 0)
296			return ret;
297
298		ret = tmag5273_get_measure(data, &t, &x, &y, &z, &angle, &magnitude);
299
300		pm_runtime_mark_last_busy(data->dev);
301		pm_runtime_put_autosuspend(data->dev);
302
303		if (ret)
304			return ret;
305
306		switch (chan->address) {
307		case TEMPERATURE:
308			*val = t;
309			return IIO_VAL_INT;
310		case AXIS_X:
311			*val = x;
312			return IIO_VAL_INT;
313		case AXIS_Y:
314			*val = y;
315			return IIO_VAL_INT;
316		case AXIS_Z:
317			*val = z;
318			return IIO_VAL_INT;
319		case ANGLE:
320			*val = angle;
321			return IIO_VAL_INT;
322		case MAGNITUDE:
323			*val = magnitude;
324			return IIO_VAL_INT;
325		default:
326			return -EINVAL;
327		}
328	case IIO_CHAN_INFO_SCALE:
329		switch (chan->type) {
330		case IIO_TEMP:
331			/*
332			 * Convert device specific value to millicelsius.
333			 * Resolution from the sensor is 60.1 LSB/celsius and
334			 * the reference value at 25 celsius is 17508 LSBs.
335			 */
336			*val = 10000;
337			*val2 = 601;
338			return IIO_VAL_FRACTIONAL;
339		case IIO_MAGN:
340			/* Magnetic resolution in uT */
341			*val = 0;
342			*val2 = tmag5273_scale[data->version]
343					      [data->scale_index].micro;
344			return IIO_VAL_INT_PLUS_MICRO;
345		case IIO_ANGL:
346			/*
347			 * Angle is in degrees and has four fractional bits,
348			 * therefore use 1/16 * pi/180 to convert to radians.
349			 */
350			*val = 1000;
351			*val2 = 916732;
352			return IIO_VAL_FRACTIONAL;
353		default:
354			return -EINVAL;
355		}
356	case IIO_CHAN_INFO_OFFSET:
357		switch (chan->type) {
358		case IIO_TEMP:
359			*val = -16005;
360			return IIO_VAL_INT;
361		default:
362			return -EINVAL;
363		}
364	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
365		*val = data->conv_avg;
366		return IIO_VAL_INT;
367
368	default:
369		return -EINVAL;
370	}
371}
372
373static int tmag5273_write_raw(struct iio_dev *indio_dev,
374			      struct iio_chan_spec const *chan, int val,
375			      int val2, long mask)
376{
377	struct tmag5273_data *data = iio_priv(indio_dev);
378
379	switch (mask) {
380	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
381		return tmag5273_write_osr(data, val);
382	case IIO_CHAN_INFO_SCALE:
383		switch (chan->type) {
384		case IIO_MAGN:
385			if (val)
386				return -EINVAL;
387			return tmag5273_write_scale(data, val2);
388		default:
389			return -EINVAL;
390		}
391	default:
392		return -EINVAL;
393	}
394}
395
396#define TMAG5273_AXIS_CHANNEL(axis, index)				     \
397	{								     \
398		.type = IIO_MAGN,					     \
399		.modified = 1,						     \
400		.channel2 = IIO_MOD_##axis,				     \
401		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |		     \
402				      BIT(IIO_CHAN_INFO_SCALE),		     \
403		.info_mask_shared_by_type_available =			     \
404				      BIT(IIO_CHAN_INFO_SCALE),		     \
405		.info_mask_shared_by_all =				     \
406				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
407		.info_mask_shared_by_all_available =			     \
408				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO), \
409		.address = index,					     \
410		.scan_index = index,					     \
411		.scan_type = {						     \
412			.sign = 's',					     \
413			.realbits = 16,					     \
414			.storagebits = 16,				     \
415			.endianness = IIO_CPU,				     \
416		},							     \
417	}
418
419static const struct iio_chan_spec tmag5273_channels[] = {
420	{
421		.type = IIO_TEMP,
422		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
423			BIT(IIO_CHAN_INFO_SCALE) |
424			BIT(IIO_CHAN_INFO_OFFSET),
425		.address = TEMPERATURE,
426		.scan_index = TEMPERATURE,
427		.scan_type = {
428			.sign = 'u',
429			.realbits = 16,
430			.storagebits = 16,
431			.endianness = IIO_CPU,
432		},
433	},
434	TMAG5273_AXIS_CHANNEL(X, AXIS_X),
435	TMAG5273_AXIS_CHANNEL(Y, AXIS_Y),
436	TMAG5273_AXIS_CHANNEL(Z, AXIS_Z),
437	{
438		.type = IIO_ANGL,
439		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
440		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
441		.info_mask_shared_by_all =
442				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
443		.info_mask_shared_by_all_available =
444				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
445		.address = ANGLE,
446		.scan_index = ANGLE,
447		.scan_type = {
448			.sign = 'u',
449			.realbits = 16,
450			.storagebits = 16,
451			.endianness = IIO_CPU,
452		},
453	},
454	{
455		.type = IIO_DISTANCE,
456		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
457		.info_mask_shared_by_all =
458				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
459		.info_mask_shared_by_all_available =
460				      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
461		.address = MAGNITUDE,
462		.scan_index = MAGNITUDE,
463		.scan_type = {
464			.sign = 'u',
465			.realbits = 16,
466			.storagebits = 16,
467			.endianness = IIO_CPU,
468		},
469	},
470	IIO_CHAN_SOFT_TIMESTAMP(6),
471};
472
473static const struct iio_info tmag5273_info = {
474	.read_avail = tmag5273_read_avail,
475	.read_raw = tmag5273_read_raw,
476	.write_raw = tmag5273_write_raw,
477};
478
479static bool tmag5273_volatile_reg(struct device *dev, unsigned int reg)
480{
481	return reg >= TMAG5273_T_MSB_RESULT && reg <= TMAG5273_MAGNITUDE_RESULT;
482}
483
484static const struct regmap_config tmag5273_regmap_config = {
485	.reg_bits = 8,
486	.val_bits = 8,
487	.max_register = TMAG5273_MAX_REG,
488	.volatile_reg = tmag5273_volatile_reg,
489};
490
491static int tmag5273_set_operating_mode(struct tmag5273_data *data,
492				       unsigned int val)
493{
494	return regmap_write(data->map, TMAG5273_DEVICE_CONFIG_2, val);
495}
496
497static void tmag5273_read_device_property(struct tmag5273_data *data)
498{
499	struct device *dev = data->dev;
500	int ret;
501
502	data->angle_measurement = TMAG5273_ANGLE_EN_X_Y;
503
504	ret = device_property_match_property_string(dev, "ti,angle-measurement",
505						    tmag5273_angle_names,
506						    ARRAY_SIZE(tmag5273_angle_names));
507	if (ret >= 0)
508		data->angle_measurement = ret;
509}
510
511static void tmag5273_wake_up(struct tmag5273_data *data)
512{
513	int val;
514
515	/* Wake up the chip by sending a dummy I2C command */
516	regmap_read(data->map, TMAG5273_DEVICE_ID, &val);
517	/*
518	 * Time to go to stand-by mode from sleep mode is 50us
519	 * typically, during this time no I2C access is possible.
520	 */
521	usleep_range(80, 200);
522}
523
524static int tmag5273_chip_init(struct tmag5273_data *data)
525{
526	int ret;
527
528	ret = regmap_write(data->map, TMAG5273_DEVICE_CONFIG_1,
529			   TMAG5273_AVG_32_MODE);
530	if (ret)
531		return ret;
532	data->conv_avg = 32;
533
534	ret = regmap_write(data->map, TMAG5273_DEVICE_CONFIG_2,
535			   TMAG5273_OP_MODE_CONT);
536	if (ret)
537		return ret;
538
539	ret = regmap_write(data->map, TMAG5273_SENSOR_CONFIG_1,
540			   FIELD_PREP(TMAG5273_MAG_CH_EN_MASK,
541				      TMAG5273_MAG_CH_EN_X_Y_Z));
542	if (ret)
543		return ret;
544
545	ret = regmap_write(data->map, TMAG5273_SENSOR_CONFIG_2,
546			   FIELD_PREP(TMAG5273_ANGLE_EN_MASK,
547				      data->angle_measurement));
548	if (ret)
549		return ret;
550	data->scale_index = MAGN_RANGE_LOW;
551
552	return regmap_write(data->map, TMAG5273_T_CONFIG, TMAG5273_T_CH_EN);
553}
554
555static int tmag5273_check_device_id(struct tmag5273_data *data)
556{
557	__le16 devid;
558	int val, ret;
559
560	ret = regmap_read(data->map, TMAG5273_DEVICE_ID, &val);
561	if (ret)
562		return dev_err_probe(data->dev, ret, "failed to power on device\n");
563	data->version = FIELD_PREP(TMAG5273_VERSION_MASK, val);
564
565	ret = regmap_bulk_read(data->map, TMAG5273_MANUFACTURER_ID_LSB, &devid,
566			       sizeof(devid));
567	if (ret)
568		return dev_err_probe(data->dev, ret, "failed to read device ID\n");
569	data->devid = le16_to_cpu(devid);
570
571	switch (data->devid) {
572	case TMAG5273_MANUFACTURER_ID:
573		/*
574		 * The device name matches the orderable part number. 'x' stands
575		 * for A, B, C or D devices, which have different I2C addresses.
576		 * Versions 1 or 2 (0 and 3 is reserved) stands for different
577		 * magnetic strengths.
578		 */
579		snprintf(data->name, sizeof(data->name), "tmag5273x%1u", data->version);
580		if (data->version < 1 || data->version > 2)
581			dev_warn(data->dev, "Unsupported device %s\n", data->name);
582		return 0;
583	default:
584		/*
585		 * Only print warning in case of unknown device ID to allow
586		 * fallback compatible in device tree.
587		 */
588		dev_warn(data->dev, "Unknown device ID 0x%x\n", data->devid);
589		return 0;
590	}
591}
592
593static void tmag5273_power_down(void *data)
594{
595	tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_SLEEP);
596}
597
598static int tmag5273_probe(struct i2c_client *i2c)
599{
600	struct device *dev = &i2c->dev;
601	struct tmag5273_data *data;
602	struct iio_dev *indio_dev;
603	int ret;
604
605	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
606	if (!indio_dev)
607		return -ENOMEM;
608
609	data = iio_priv(indio_dev);
610	data->dev = dev;
611	i2c_set_clientdata(i2c, indio_dev);
612
613	data->map = devm_regmap_init_i2c(i2c, &tmag5273_regmap_config);
614	if (IS_ERR(data->map))
615		return dev_err_probe(dev, PTR_ERR(data->map),
616				     "failed to allocate register map\n");
617
618	mutex_init(&data->lock);
619
620	ret = devm_regulator_get_enable(dev, "vcc");
621	if (ret)
622		return dev_err_probe(dev, ret, "failed to enable regulator\n");
623
624	tmag5273_wake_up(data);
625
626	ret = tmag5273_check_device_id(data);
627	if (ret)
628		return ret;
629
630	ret = tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_CONT);
631	if (ret)
632		return dev_err_probe(dev, ret, "failed to power on device\n");
633
634	/*
635	 * Register powerdown deferred callback which suspends the chip
636	 * after module unloaded.
637	 *
638	 * TMAG5273 should be in SUSPEND mode in the two cases:
639	 * 1) When driver is loaded, but we do not have any data or
640	 *    configuration requests to it (we are solving it using
641	 *    autosuspend feature).
642	 * 2) When driver is unloaded and device is not used (devm action is
643	 *    used in this case).
644	 */
645	ret = devm_add_action_or_reset(dev, tmag5273_power_down, data);
646	if (ret)
647		return dev_err_probe(dev, ret, "failed to add powerdown action\n");
648
649	ret = pm_runtime_set_active(dev);
650	if (ret < 0)
651		return ret;
652
653	ret = devm_pm_runtime_enable(dev);
654	if (ret)
655		return ret;
656
657	pm_runtime_get_noresume(dev);
658	pm_runtime_set_autosuspend_delay(dev, TMAG5273_AUTOSLEEP_DELAY_MS);
659	pm_runtime_use_autosuspend(dev);
660
661	tmag5273_read_device_property(data);
662
663	ret = tmag5273_chip_init(data);
664	if (ret)
665		return dev_err_probe(dev, ret, "failed to init device\n");
666
667	indio_dev->info = &tmag5273_info;
668	indio_dev->modes = INDIO_DIRECT_MODE;
669	indio_dev->name = data->name;
670	indio_dev->channels = tmag5273_channels;
671	indio_dev->num_channels = ARRAY_SIZE(tmag5273_channels);
672
673	pm_runtime_mark_last_busy(dev);
674	pm_runtime_put_autosuspend(dev);
675
676	ret = devm_iio_device_register(dev, indio_dev);
677	if (ret)
678		return dev_err_probe(dev, ret, "device register failed\n");
679
680	return 0;
681}
682
683static int tmag5273_runtime_suspend(struct device *dev)
684{
685	struct iio_dev *indio_dev = dev_get_drvdata(dev);
686	struct tmag5273_data *data = iio_priv(indio_dev);
687	int ret;
688
689	ret = tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_SLEEP);
690	if (ret)
691		dev_err(dev, "failed to power off device (%pe)\n", ERR_PTR(ret));
692
693	return ret;
694}
695
696static int tmag5273_runtime_resume(struct device *dev)
697{
698	struct iio_dev *indio_dev = dev_get_drvdata(dev);
699	struct tmag5273_data *data = iio_priv(indio_dev);
700	int ret;
701
702	tmag5273_wake_up(data);
703
704	ret = tmag5273_set_operating_mode(data, TMAG5273_OP_MODE_CONT);
705	if (ret)
706		dev_err(dev, "failed to power on device (%pe)\n", ERR_PTR(ret));
707
708	return ret;
709}
710
711static DEFINE_RUNTIME_DEV_PM_OPS(tmag5273_pm_ops,
712				 tmag5273_runtime_suspend, tmag5273_runtime_resume,
713				 NULL);
714
715static const struct i2c_device_id tmag5273_id[] = {
716	{ "tmag5273" },
717	{ /* sentinel */ }
718};
719MODULE_DEVICE_TABLE(i2c, tmag5273_id);
720
721static const struct of_device_id tmag5273_of_match[] = {
722	{ .compatible = "ti,tmag5273" },
723	{ /* sentinel */ }
724};
725MODULE_DEVICE_TABLE(of, tmag5273_of_match);
726
727static struct i2c_driver tmag5273_driver = {
728	.driver	 = {
729		.name = "tmag5273",
730		.of_match_table = tmag5273_of_match,
731		.pm = pm_ptr(&tmag5273_pm_ops),
732	},
733	.probe = tmag5273_probe,
734	.id_table = tmag5273_id,
735};
736module_i2c_driver(tmag5273_driver);
737
738MODULE_DESCRIPTION("TI TMAG5273 Low-Power Linear 3D Hall-Effect Sensor driver");
739MODULE_AUTHOR("Gerald Loacker <gerald.loacker@wolfvision.net>");
740MODULE_LICENSE("GPL");
741