xref: /linux/drivers/iio/magnetometer/bmc150_magn.c (revision cb4eb6771c0f8fd1c52a8f6fdec7762fb087380a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Bosch BMC150 three-axis magnetic field sensor driver
4  *
5  * Copyright (c) 2015, Intel Corporation.
6  *
7  * This code is based on bmm050_api.c authored by contact@bosch.sensortec.com:
8  *
9  * (C) Copyright 2011~2014 Bosch Sensortec GmbH All Rights Reserved
10  */
11 
12 #include <linux/module.h>
13 #include <linux/i2c.h>
14 #include <linux/interrupt.h>
15 #include <linux/cleanup.h>
16 #include <linux/delay.h>
17 #include <linux/slab.h>
18 #include <linux/pm.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/buffer.h>
23 #include <linux/iio/events.h>
24 #include <linux/iio/trigger.h>
25 #include <linux/iio/trigger_consumer.h>
26 #include <linux/iio/triggered_buffer.h>
27 #include <linux/regmap.h>
28 #include <linux/regulator/consumer.h>
29 
30 #include "bmc150_magn.h"
31 
32 #define BMC150_MAGN_REG_CHIP_ID			0x40
33 #define BMC150_MAGN_CHIP_ID_VAL			0x32
34 
35 #define BMC150_MAGN_REG_X_L			0x42
36 #define BMC150_MAGN_REG_X_M			0x43
37 #define BMC150_MAGN_REG_Y_L			0x44
38 #define BMC150_MAGN_REG_Y_M			0x45
39 #define BMC150_MAGN_SHIFT_XY_L			3
40 #define BMC150_MAGN_REG_Z_L			0x46
41 #define BMC150_MAGN_REG_Z_M			0x47
42 #define BMC150_MAGN_SHIFT_Z_L			1
43 #define BMC150_MAGN_REG_RHALL_L			0x48
44 #define BMC150_MAGN_REG_RHALL_M			0x49
45 #define BMC150_MAGN_SHIFT_RHALL_L		2
46 
47 #define BMC150_MAGN_REG_INT_STATUS		0x4A
48 
49 #define BMC150_MAGN_REG_POWER			0x4B
50 #define BMC150_MAGN_MASK_POWER_CTL		BIT(0)
51 
52 #define BMC150_MAGN_REG_OPMODE_ODR		0x4C
53 #define BMC150_MAGN_MASK_OPMODE			GENMASK(2, 1)
54 #define BMC150_MAGN_SHIFT_OPMODE		1
55 #define BMC150_MAGN_MODE_NORMAL			0x00
56 #define BMC150_MAGN_MODE_FORCED			0x01
57 #define BMC150_MAGN_MODE_SLEEP			0x03
58 #define BMC150_MAGN_MASK_ODR			GENMASK(5, 3)
59 #define BMC150_MAGN_SHIFT_ODR			3
60 
61 #define BMC150_MAGN_REG_INT			0x4D
62 
63 #define BMC150_MAGN_REG_INT_DRDY		0x4E
64 #define BMC150_MAGN_MASK_DRDY_EN		BIT(7)
65 #define BMC150_MAGN_SHIFT_DRDY_EN		7
66 #define BMC150_MAGN_MASK_DRDY_INT3		BIT(6)
67 #define BMC150_MAGN_MASK_DRDY_Z_EN		BIT(5)
68 #define BMC150_MAGN_MASK_DRDY_Y_EN		BIT(4)
69 #define BMC150_MAGN_MASK_DRDY_X_EN		BIT(3)
70 #define BMC150_MAGN_MASK_DRDY_DR_POLARITY	BIT(2)
71 #define BMC150_MAGN_MASK_DRDY_LATCHING		BIT(1)
72 #define BMC150_MAGN_MASK_DRDY_INT3_POLARITY	BIT(0)
73 
74 #define BMC150_MAGN_REG_LOW_THRESH		0x4F
75 #define BMC150_MAGN_REG_HIGH_THRESH		0x50
76 #define BMC150_MAGN_REG_REP_XY			0x51
77 #define BMC150_MAGN_REG_REP_Z			0x52
78 #define BMC150_MAGN_REG_REP_DATAMASK		GENMASK(7, 0)
79 
80 #define BMC150_MAGN_REG_TRIM_START		0x5D
81 #define BMC150_MAGN_REG_TRIM_END		0x71
82 
83 #define BMC150_MAGN_XY_OVERFLOW_VAL		-4096
84 #define BMC150_MAGN_Z_OVERFLOW_VAL		-16384
85 
86 /* Time from SUSPEND to SLEEP */
87 #define BMC150_MAGN_START_UP_TIME_MS		3
88 
89 #define BMC150_MAGN_AUTO_SUSPEND_DELAY_MS	2000
90 
91 #define BMC150_MAGN_REGVAL_TO_REPXY(regval) (((regval) * 2) + 1)
92 #define BMC150_MAGN_REGVAL_TO_REPZ(regval) ((regval) + 1)
93 #define BMC150_MAGN_REPXY_TO_REGVAL(rep) (((rep) - 1) / 2)
94 #define BMC150_MAGN_REPZ_TO_REGVAL(rep) ((rep) - 1)
95 
96 enum bmc150_magn_axis {
97 	AXIS_X,
98 	AXIS_Y,
99 	AXIS_Z,
100 	RHALL,
101 	AXIS_XYZ_MAX = RHALL,
102 	AXIS_XYZR_MAX,
103 };
104 
105 enum bmc150_magn_power_modes {
106 	BMC150_MAGN_POWER_MODE_SUSPEND,
107 	BMC150_MAGN_POWER_MODE_SLEEP,
108 	BMC150_MAGN_POWER_MODE_NORMAL,
109 };
110 
111 struct bmc150_magn_trim_regs {
112 	s8 x1;
113 	s8 y1;
114 	__le16 reserved1;
115 	u8 reserved2;
116 	__le16 z4;
117 	s8 x2;
118 	s8 y2;
119 	__le16 reserved3;
120 	__le16 z2;
121 	__le16 z1;
122 	__le16 xyz1;
123 	__le16 z3;
124 	s8 xy2;
125 	u8 xy1;
126 } __packed;
127 
128 struct bmc150_magn_data {
129 	struct device *dev;
130 	/*
131 	 * 1. Protect this structure.
132 	 * 2. Serialize sequences that power on/off the device and access HW.
133 	 */
134 	struct mutex mutex;
135 	struct regmap *regmap;
136 	struct regulator_bulk_data regulators[2];
137 	struct iio_mount_matrix orientation;
138 	/* Ensure timestamp is naturally aligned */
139 	struct {
140 		s32 chans[3];
141 		aligned_s64 timestamp;
142 	} scan;
143 	struct iio_trigger *dready_trig;
144 	bool dready_trigger_on;
145 	int max_odr;
146 	int irq;
147 };
148 
149 static const struct {
150 	int freq;
151 	u8 reg_val;
152 } bmc150_magn_samp_freq_table[] = {
153 	{ 2, 0x01 },
154 	{ 6, 0x02 },
155 	{ 8, 0x03 },
156 	{ 10, 0x00 },
157 	{ 15, 0x04 },
158 	{ 20, 0x05 },
159 	{ 25, 0x06 },
160 	{ 30, 0x07 },
161 };
162 
163 enum bmc150_magn_presets {
164 	LOW_POWER_PRESET,
165 	REGULAR_PRESET,
166 	ENHANCED_REGULAR_PRESET,
167 	HIGH_ACCURACY_PRESET
168 };
169 
170 static const struct bmc150_magn_preset {
171 	u8 rep_xy;
172 	u8 rep_z;
173 	u8 odr;
174 } bmc150_magn_presets_table[] = {
175 	[LOW_POWER_PRESET] = { 3, 3, 10 },
176 	[REGULAR_PRESET] = { 9, 15, 10 },
177 	[ENHANCED_REGULAR_PRESET] = { 15, 27, 10 },
178 	[HIGH_ACCURACY_PRESET] = { 47, 83, 20 },
179 };
180 
181 #define BMC150_MAGN_DEFAULT_PRESET REGULAR_PRESET
182 
bmc150_magn_is_writeable_reg(struct device * dev,unsigned int reg)183 static bool bmc150_magn_is_writeable_reg(struct device *dev, unsigned int reg)
184 {
185 	switch (reg) {
186 	case BMC150_MAGN_REG_POWER:
187 	case BMC150_MAGN_REG_OPMODE_ODR:
188 	case BMC150_MAGN_REG_INT:
189 	case BMC150_MAGN_REG_INT_DRDY:
190 	case BMC150_MAGN_REG_LOW_THRESH:
191 	case BMC150_MAGN_REG_HIGH_THRESH:
192 	case BMC150_MAGN_REG_REP_XY:
193 	case BMC150_MAGN_REG_REP_Z:
194 		return true;
195 	default:
196 		return false;
197 	}
198 }
199 
bmc150_magn_is_volatile_reg(struct device * dev,unsigned int reg)200 static bool bmc150_magn_is_volatile_reg(struct device *dev, unsigned int reg)
201 {
202 	switch (reg) {
203 	case BMC150_MAGN_REG_X_L:
204 	case BMC150_MAGN_REG_X_M:
205 	case BMC150_MAGN_REG_Y_L:
206 	case BMC150_MAGN_REG_Y_M:
207 	case BMC150_MAGN_REG_Z_L:
208 	case BMC150_MAGN_REG_Z_M:
209 	case BMC150_MAGN_REG_RHALL_L:
210 	case BMC150_MAGN_REG_RHALL_M:
211 	case BMC150_MAGN_REG_INT_STATUS:
212 		return true;
213 	default:
214 		return false;
215 	}
216 }
217 
218 const struct regmap_config bmc150_magn_regmap_config = {
219 	.reg_bits = 8,
220 	.val_bits = 8,
221 
222 	.max_register = BMC150_MAGN_REG_TRIM_END,
223 	.cache_type = REGCACHE_RBTREE,
224 
225 	.writeable_reg = bmc150_magn_is_writeable_reg,
226 	.volatile_reg = bmc150_magn_is_volatile_reg,
227 };
228 EXPORT_SYMBOL_NS(bmc150_magn_regmap_config, "IIO_BMC150_MAGN");
229 
bmc150_magn_set_power_mode(struct bmc150_magn_data * data,enum bmc150_magn_power_modes mode,bool state)230 static int bmc150_magn_set_power_mode(struct bmc150_magn_data *data,
231 				      enum bmc150_magn_power_modes mode,
232 				      bool state)
233 {
234 	int ret;
235 
236 	switch (mode) {
237 	case BMC150_MAGN_POWER_MODE_SUSPEND:
238 		ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_POWER,
239 					 BMC150_MAGN_MASK_POWER_CTL, !state);
240 		if (ret < 0)
241 			return ret;
242 		usleep_range(BMC150_MAGN_START_UP_TIME_MS * 1000, 20000);
243 		return 0;
244 	case BMC150_MAGN_POWER_MODE_SLEEP:
245 		return regmap_update_bits(data->regmap,
246 					  BMC150_MAGN_REG_OPMODE_ODR,
247 					  BMC150_MAGN_MASK_OPMODE,
248 					  BMC150_MAGN_MODE_SLEEP <<
249 					  BMC150_MAGN_SHIFT_OPMODE);
250 	case BMC150_MAGN_POWER_MODE_NORMAL:
251 		return regmap_update_bits(data->regmap,
252 					  BMC150_MAGN_REG_OPMODE_ODR,
253 					  BMC150_MAGN_MASK_OPMODE,
254 					  BMC150_MAGN_MODE_NORMAL <<
255 					  BMC150_MAGN_SHIFT_OPMODE);
256 	}
257 
258 	return -EINVAL;
259 }
260 
bmc150_magn_set_power_mode_locked(struct bmc150_magn_data * data,enum bmc150_magn_power_modes mode)261 static int bmc150_magn_set_power_mode_locked(struct bmc150_magn_data *data,
262 					     enum bmc150_magn_power_modes mode)
263 {
264 	guard(mutex)(&data->mutex);
265 	return bmc150_magn_set_power_mode(data, mode, true);
266 }
267 
bmc150_magn_set_power_state(struct bmc150_magn_data * data,bool on)268 static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
269 {
270 	int ret = 0;
271 
272 	if (on)
273 		ret = pm_runtime_resume_and_get(data->dev);
274 	else
275 		pm_runtime_put_autosuspend(data->dev);
276 	if (ret < 0) {
277 		dev_err(data->dev,
278 			"failed to change power state to %d\n", on);
279 		return ret;
280 	}
281 
282 	return 0;
283 }
284 
bmc150_magn_get_odr(struct bmc150_magn_data * data,int * val)285 static int bmc150_magn_get_odr(struct bmc150_magn_data *data, int *val)
286 {
287 	int ret, reg_val;
288 	u8 i, odr_val;
289 
290 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_OPMODE_ODR, &reg_val);
291 	if (ret < 0)
292 		return ret;
293 	odr_val = (reg_val & BMC150_MAGN_MASK_ODR) >> BMC150_MAGN_SHIFT_ODR;
294 
295 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++)
296 		if (bmc150_magn_samp_freq_table[i].reg_val == odr_val) {
297 			*val = bmc150_magn_samp_freq_table[i].freq;
298 			return 0;
299 		}
300 
301 	return -EINVAL;
302 }
303 
bmc150_magn_set_odr(struct bmc150_magn_data * data,int val)304 static int bmc150_magn_set_odr(struct bmc150_magn_data *data, int val)
305 {
306 	int ret;
307 	u8 i;
308 
309 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
310 		if (bmc150_magn_samp_freq_table[i].freq == val) {
311 			ret = regmap_update_bits(data->regmap,
312 						 BMC150_MAGN_REG_OPMODE_ODR,
313 						 BMC150_MAGN_MASK_ODR,
314 						 bmc150_magn_samp_freq_table[i].
315 						 reg_val <<
316 						 BMC150_MAGN_SHIFT_ODR);
317 			if (ret < 0)
318 				return ret;
319 			return 0;
320 		}
321 	}
322 
323 	return -EINVAL;
324 }
325 
bmc150_magn_set_max_odr(struct bmc150_magn_data * data,int rep_xy,int rep_z,int odr)326 static int bmc150_magn_set_max_odr(struct bmc150_magn_data *data, int rep_xy,
327 				   int rep_z, int odr)
328 {
329 	int ret, reg_val, max_odr;
330 
331 	if (rep_xy <= 0) {
332 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
333 				  &reg_val);
334 		if (ret < 0)
335 			return ret;
336 		rep_xy = BMC150_MAGN_REGVAL_TO_REPXY(reg_val);
337 	}
338 	if (rep_z <= 0) {
339 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
340 				  &reg_val);
341 		if (ret < 0)
342 			return ret;
343 		rep_z = BMC150_MAGN_REGVAL_TO_REPZ(reg_val);
344 	}
345 	if (odr <= 0) {
346 		ret = bmc150_magn_get_odr(data, &odr);
347 		if (ret < 0)
348 			return ret;
349 	}
350 	/* the maximum selectable read-out frequency from datasheet */
351 	max_odr = 1000000 / (145 * rep_xy + 500 * rep_z + 980);
352 	if (odr > max_odr) {
353 		dev_err(data->dev,
354 			"Can't set oversampling with sampling freq %d\n",
355 			odr);
356 		return -EINVAL;
357 	}
358 	data->max_odr = max_odr;
359 
360 	return 0;
361 }
362 
bmc150_magn_compensate_x(struct bmc150_magn_trim_regs * tregs,s16 x,u16 rhall)363 static s32 bmc150_magn_compensate_x(struct bmc150_magn_trim_regs *tregs, s16 x,
364 				    u16 rhall)
365 {
366 	s16 val;
367 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
368 
369 	if (x == BMC150_MAGN_XY_OVERFLOW_VAL)
370 		return S32_MIN;
371 
372 	if (!rhall)
373 		rhall = xyz1;
374 
375 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
376 	val = ((s16)((((s32)x) * ((((((((s32)tregs->xy2) * ((((s32)val) *
377 	      ((s32)val)) >> 7)) + (((s32)val) *
378 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
379 	      ((s32)(((s16)tregs->x2) + ((s16)0xA0)))) >> 12)) >> 13)) +
380 	      (((s16)tregs->x1) << 3);
381 
382 	return (s32)val;
383 }
384 
bmc150_magn_compensate_y(struct bmc150_magn_trim_regs * tregs,s16 y,u16 rhall)385 static s32 bmc150_magn_compensate_y(struct bmc150_magn_trim_regs *tregs, s16 y,
386 				    u16 rhall)
387 {
388 	s16 val;
389 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
390 
391 	if (y == BMC150_MAGN_XY_OVERFLOW_VAL)
392 		return S32_MIN;
393 
394 	if (!rhall)
395 		rhall = xyz1;
396 
397 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
398 	val = ((s16)((((s32)y) * ((((((((s32)tregs->xy2) * ((((s32)val) *
399 	      ((s32)val)) >> 7)) + (((s32)val) *
400 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
401 	      ((s32)(((s16)tregs->y2) + ((s16)0xA0)))) >> 12)) >> 13)) +
402 	      (((s16)tregs->y1) << 3);
403 
404 	return (s32)val;
405 }
406 
bmc150_magn_compensate_z(struct bmc150_magn_trim_regs * tregs,s16 z,u16 rhall)407 static s32 bmc150_magn_compensate_z(struct bmc150_magn_trim_regs *tregs, s16 z,
408 				    u16 rhall)
409 {
410 	s32 val;
411 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
412 	u16 z1 = le16_to_cpu(tregs->z1);
413 	s16 z2 = le16_to_cpu(tregs->z2);
414 	s16 z3 = le16_to_cpu(tregs->z3);
415 	s16 z4 = le16_to_cpu(tregs->z4);
416 
417 	if (z == BMC150_MAGN_Z_OVERFLOW_VAL)
418 		return S32_MIN;
419 
420 	val = (((((s32)(z - z4)) << 15) - ((((s32)z3) * ((s32)(((s16)rhall) -
421 	      ((s16)xyz1)))) >> 2)) / (z2 + ((s16)(((((s32)z1) *
422 	      ((((s16)rhall) << 1))) + (1 << 15)) >> 16))));
423 
424 	return val;
425 }
426 
bmc150_magn_read_xyz(struct bmc150_magn_data * data,s32 * buffer)427 static int bmc150_magn_read_xyz(struct bmc150_magn_data *data, s32 *buffer)
428 {
429 	int ret;
430 	__le16 values[AXIS_XYZR_MAX];
431 	s16 raw_x, raw_y, raw_z;
432 	u16 rhall;
433 	struct bmc150_magn_trim_regs tregs;
434 
435 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_X_L,
436 			       values, sizeof(values));
437 	if (ret < 0)
438 		return ret;
439 
440 	raw_x = (s16)le16_to_cpu(values[AXIS_X]) >> BMC150_MAGN_SHIFT_XY_L;
441 	raw_y = (s16)le16_to_cpu(values[AXIS_Y]) >> BMC150_MAGN_SHIFT_XY_L;
442 	raw_z = (s16)le16_to_cpu(values[AXIS_Z]) >> BMC150_MAGN_SHIFT_Z_L;
443 	rhall = le16_to_cpu(values[RHALL]) >> BMC150_MAGN_SHIFT_RHALL_L;
444 
445 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_TRIM_START,
446 			       &tregs, sizeof(tregs));
447 	if (ret < 0)
448 		return ret;
449 
450 	buffer[AXIS_X] = bmc150_magn_compensate_x(&tregs, raw_x, rhall);
451 	buffer[AXIS_Y] = bmc150_magn_compensate_y(&tregs, raw_y, rhall);
452 	buffer[AXIS_Z] = bmc150_magn_compensate_z(&tregs, raw_z, rhall);
453 
454 	return 0;
455 }
456 
bmc150_magn_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)457 static int bmc150_magn_read_raw(struct iio_dev *indio_dev,
458 				struct iio_chan_spec const *chan,
459 				int *val, int *val2, long mask)
460 {
461 	struct bmc150_magn_data *data = iio_priv(indio_dev);
462 	int ret, tmp;
463 	s32 values[AXIS_XYZ_MAX];
464 
465 	switch (mask) {
466 	case IIO_CHAN_INFO_RAW: {
467 		if (iio_buffer_enabled(indio_dev))
468 			return -EBUSY;
469 
470 		guard(mutex)(&data->mutex);
471 
472 		ret = bmc150_magn_set_power_state(data, true);
473 		if (ret < 0)
474 			return ret;
475 
476 		ret = bmc150_magn_read_xyz(data, values);
477 		if (ret < 0) {
478 			bmc150_magn_set_power_state(data, false);
479 			return ret;
480 		}
481 		*val = values[chan->scan_index];
482 
483 		ret = bmc150_magn_set_power_state(data, false);
484 		if (ret < 0)
485 			return ret;
486 
487 		return IIO_VAL_INT;
488 	}
489 	case IIO_CHAN_INFO_SCALE:
490 		/*
491 		 * The API/driver performs an off-chip temperature
492 		 * compensation and outputs x/y/z magnetic field data in
493 		 * 16 LSB/uT to the upper application layer.
494 		 */
495 		*val = 0;
496 		*val2 = 625;
497 		return IIO_VAL_INT_PLUS_MICRO;
498 	case IIO_CHAN_INFO_SAMP_FREQ:
499 		ret = bmc150_magn_get_odr(data, val);
500 		if (ret < 0)
501 			return ret;
502 		return IIO_VAL_INT;
503 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
504 		switch (chan->channel2) {
505 		case IIO_MOD_X:
506 		case IIO_MOD_Y:
507 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
508 					  &tmp);
509 			if (ret < 0)
510 				return ret;
511 			*val = BMC150_MAGN_REGVAL_TO_REPXY(tmp);
512 			return IIO_VAL_INT;
513 		case IIO_MOD_Z:
514 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
515 					  &tmp);
516 			if (ret < 0)
517 				return ret;
518 			*val = BMC150_MAGN_REGVAL_TO_REPZ(tmp);
519 			return IIO_VAL_INT;
520 		default:
521 			return -EINVAL;
522 		}
523 	default:
524 		return -EINVAL;
525 	}
526 }
527 
bmc150_magn_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)528 static int bmc150_magn_write_raw(struct iio_dev *indio_dev,
529 				 struct iio_chan_spec const *chan,
530 				 int val, int val2, long mask)
531 {
532 	struct bmc150_magn_data *data = iio_priv(indio_dev);
533 	int ret;
534 
535 	switch (mask) {
536 	case IIO_CHAN_INFO_SAMP_FREQ: {
537 		if (val > data->max_odr)
538 			return -EINVAL;
539 		guard(mutex)(&data->mutex);
540 		return bmc150_magn_set_odr(data, val);
541 	}
542 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
543 		switch (chan->channel2) {
544 		case IIO_MOD_X:
545 		case IIO_MOD_Y: {
546 			if (val < 1 || val > 511)
547 				return -EINVAL;
548 			guard(mutex)(&data->mutex);
549 			ret = bmc150_magn_set_max_odr(data, val, 0, 0);
550 			if (ret < 0)
551 				return ret;
552 			return regmap_update_bits(data->regmap,
553 						 BMC150_MAGN_REG_REP_XY,
554 						 BMC150_MAGN_REG_REP_DATAMASK,
555 						 BMC150_MAGN_REPXY_TO_REGVAL(val));
556 		}
557 		case IIO_MOD_Z: {
558 			if (val < 1 || val > 256)
559 				return -EINVAL;
560 			guard(mutex)(&data->mutex);
561 			ret = bmc150_magn_set_max_odr(data, 0, val, 0);
562 			if (ret < 0)
563 				return ret;
564 			return regmap_update_bits(data->regmap,
565 						 BMC150_MAGN_REG_REP_Z,
566 						 BMC150_MAGN_REG_REP_DATAMASK,
567 						 BMC150_MAGN_REPZ_TO_REGVAL(val));
568 		}
569 		default:
570 			return -EINVAL;
571 		}
572 	default:
573 		return -EINVAL;
574 	}
575 }
576 
bmc150_magn_show_samp_freq_avail(struct device * dev,struct device_attribute * attr,char * buf)577 static ssize_t bmc150_magn_show_samp_freq_avail(struct device *dev,
578 						struct device_attribute *attr,
579 						char *buf)
580 {
581 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
582 	struct bmc150_magn_data *data = iio_priv(indio_dev);
583 	size_t len = 0;
584 	u8 i;
585 
586 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
587 		if (bmc150_magn_samp_freq_table[i].freq > data->max_odr)
588 			break;
589 		len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
590 				 bmc150_magn_samp_freq_table[i].freq);
591 	}
592 	/* replace last space with a newline */
593 	buf[len - 1] = '\n';
594 
595 	return len;
596 }
597 
598 static const struct iio_mount_matrix *
bmc150_magn_get_mount_matrix(const struct iio_dev * indio_dev,const struct iio_chan_spec * chan)599 bmc150_magn_get_mount_matrix(const struct iio_dev *indio_dev,
600 			      const struct iio_chan_spec *chan)
601 {
602 	struct bmc150_magn_data *data = iio_priv(indio_dev);
603 
604 	return &data->orientation;
605 }
606 
607 static const struct iio_chan_spec_ext_info bmc150_magn_ext_info[] = {
608 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bmc150_magn_get_mount_matrix),
609 	{ }
610 };
611 
612 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(bmc150_magn_show_samp_freq_avail);
613 
614 static struct attribute *bmc150_magn_attributes[] = {
615 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
616 	NULL,
617 };
618 
619 static const struct attribute_group bmc150_magn_attrs_group = {
620 	.attrs = bmc150_magn_attributes,
621 };
622 
623 #define BMC150_MAGN_CHANNEL(_axis) {					\
624 	.type = IIO_MAGN,						\
625 	.modified = 1,							\
626 	.channel2 = IIO_MOD_##_axis,					\
627 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
628 			      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
629 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |	\
630 				    BIT(IIO_CHAN_INFO_SCALE),		\
631 	.scan_index = AXIS_##_axis,					\
632 	.scan_type = {							\
633 		.sign = 's',						\
634 		.realbits = 32,						\
635 		.storagebits = 32,					\
636 		.endianness = IIO_LE					\
637 	},								\
638 	.ext_info = bmc150_magn_ext_info,				\
639 }
640 
641 static const struct iio_chan_spec bmc150_magn_channels[] = {
642 	BMC150_MAGN_CHANNEL(X),
643 	BMC150_MAGN_CHANNEL(Y),
644 	BMC150_MAGN_CHANNEL(Z),
645 	IIO_CHAN_SOFT_TIMESTAMP(3),
646 };
647 
648 static const struct iio_info bmc150_magn_info = {
649 	.attrs = &bmc150_magn_attrs_group,
650 	.read_raw = bmc150_magn_read_raw,
651 	.write_raw = bmc150_magn_write_raw,
652 };
653 
654 static const unsigned long bmc150_magn_scan_masks[] = {
655 	BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
656 	0
657 };
658 
bmc150_magn_trigger_handler(int irq,void * p)659 static irqreturn_t bmc150_magn_trigger_handler(int irq, void *p)
660 {
661 	struct iio_poll_func *pf = p;
662 	struct iio_dev *indio_dev = pf->indio_dev;
663 	struct bmc150_magn_data *data = iio_priv(indio_dev);
664 	int ret;
665 
666 	mutex_lock(&data->mutex);
667 	ret = bmc150_magn_read_xyz(data, data->scan.chans);
668 	if (ret < 0)
669 		goto err;
670 
671 	iio_push_to_buffers_with_ts(indio_dev, &data->scan, sizeof(data->scan),
672 				    pf->timestamp);
673 
674 err:
675 	mutex_unlock(&data->mutex);
676 	iio_trigger_notify_done(indio_dev->trig);
677 
678 	return IRQ_HANDLED;
679 }
680 
bmc150_magn_init(struct bmc150_magn_data * data)681 static int bmc150_magn_init(struct bmc150_magn_data *data)
682 {
683 	int ret, chip_id;
684 	struct bmc150_magn_preset preset;
685 
686 	ret = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
687 				    data->regulators);
688 	if (ret < 0) {
689 		dev_err(data->dev, "Failed to enable regulators: %d\n", ret);
690 		return ret;
691 	}
692 	/*
693 	 * 3ms power-on time according to datasheet, let's better
694 	 * be safe than sorry and set this delay to 5ms.
695 	 */
696 	fsleep(5 * USEC_PER_MSEC);
697 
698 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND,
699 					 false);
700 	if (ret < 0) {
701 		dev_err(data->dev,
702 			"Failed to bring up device from suspend mode\n");
703 		goto err_regulator_disable;
704 	}
705 
706 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_CHIP_ID, &chip_id);
707 	if (ret < 0) {
708 		dev_err(data->dev, "Failed reading chip id\n");
709 		goto err_poweroff;
710 	}
711 	if (chip_id != BMC150_MAGN_CHIP_ID_VAL) {
712 		dev_err(data->dev, "Invalid chip id 0x%x\n", chip_id);
713 		ret = -ENODEV;
714 		goto err_poweroff;
715 	}
716 	dev_dbg(data->dev, "Chip id %x\n", chip_id);
717 
718 	preset = bmc150_magn_presets_table[BMC150_MAGN_DEFAULT_PRESET];
719 	ret = bmc150_magn_set_odr(data, preset.odr);
720 	if (ret < 0) {
721 		dev_err(data->dev, "Failed to set ODR to %d\n",
722 			preset.odr);
723 		goto err_poweroff;
724 	}
725 
726 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_XY,
727 			   BMC150_MAGN_REPXY_TO_REGVAL(preset.rep_xy));
728 	if (ret < 0) {
729 		dev_err(data->dev, "Failed to set REP XY to %d\n",
730 			preset.rep_xy);
731 		goto err_poweroff;
732 	}
733 
734 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_Z,
735 			   BMC150_MAGN_REPZ_TO_REGVAL(preset.rep_z));
736 	if (ret < 0) {
737 		dev_err(data->dev, "Failed to set REP Z to %d\n",
738 			preset.rep_z);
739 		goto err_poweroff;
740 	}
741 
742 	ret = bmc150_magn_set_max_odr(data, preset.rep_xy, preset.rep_z,
743 				      preset.odr);
744 	if (ret < 0)
745 		goto err_poweroff;
746 
747 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
748 					 true);
749 	if (ret < 0) {
750 		dev_err(data->dev, "Failed to power on device\n");
751 		goto err_poweroff;
752 	}
753 
754 	return 0;
755 
756 err_poweroff:
757 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
758 err_regulator_disable:
759 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
760 	return ret;
761 }
762 
bmc150_magn_reset_intr(struct bmc150_magn_data * data)763 static int bmc150_magn_reset_intr(struct bmc150_magn_data *data)
764 {
765 	int tmp;
766 
767 	/*
768 	 * Data Ready (DRDY) is always cleared after
769 	 * readout of data registers ends.
770 	 */
771 	return regmap_read(data->regmap, BMC150_MAGN_REG_X_L, &tmp);
772 }
773 
bmc150_magn_trig_reen(struct iio_trigger * trig)774 static void bmc150_magn_trig_reen(struct iio_trigger *trig)
775 {
776 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
777 	struct bmc150_magn_data *data = iio_priv(indio_dev);
778 	int ret;
779 
780 	if (!data->dready_trigger_on)
781 		return;
782 
783 	guard(mutex)(&data->mutex);
784 	ret = bmc150_magn_reset_intr(data);
785 	if (ret)
786 		dev_err(data->dev, "Failed to reset interrupt\n");
787 }
788 
bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger * trig,bool state)789 static int bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger *trig,
790 						  bool state)
791 {
792 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
793 	struct bmc150_magn_data *data = iio_priv(indio_dev);
794 	int ret;
795 
796 	guard(mutex)(&data->mutex);
797 
798 	if (state == data->dready_trigger_on)
799 		return 0;
800 
801 	ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_INT_DRDY,
802 				 BMC150_MAGN_MASK_DRDY_EN,
803 				 state << BMC150_MAGN_SHIFT_DRDY_EN);
804 	if (ret < 0)
805 		return ret;
806 
807 	data->dready_trigger_on = state;
808 
809 	if (state) {
810 		ret = bmc150_magn_reset_intr(data);
811 		if (ret < 0)
812 			return ret;
813 	}
814 
815 	return 0;
816 }
817 
818 static const struct iio_trigger_ops bmc150_magn_trigger_ops = {
819 	.set_trigger_state = bmc150_magn_data_rdy_trigger_set_state,
820 	.reenable = bmc150_magn_trig_reen,
821 };
822 
bmc150_magn_buffer_preenable(struct iio_dev * indio_dev)823 static int bmc150_magn_buffer_preenable(struct iio_dev *indio_dev)
824 {
825 	struct bmc150_magn_data *data = iio_priv(indio_dev);
826 
827 	return bmc150_magn_set_power_state(data, true);
828 }
829 
bmc150_magn_buffer_postdisable(struct iio_dev * indio_dev)830 static int bmc150_magn_buffer_postdisable(struct iio_dev *indio_dev)
831 {
832 	struct bmc150_magn_data *data = iio_priv(indio_dev);
833 
834 	return bmc150_magn_set_power_state(data, false);
835 }
836 
837 static const struct iio_buffer_setup_ops bmc150_magn_buffer_setup_ops = {
838 	.preenable = bmc150_magn_buffer_preenable,
839 	.postdisable = bmc150_magn_buffer_postdisable,
840 };
841 
bmc150_magn_probe(struct device * dev,struct regmap * regmap,int irq,const char * name)842 int bmc150_magn_probe(struct device *dev, struct regmap *regmap,
843 		      int irq, const char *name)
844 {
845 	struct bmc150_magn_data *data;
846 	struct iio_dev *indio_dev;
847 	int ret;
848 
849 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
850 	if (!indio_dev)
851 		return -ENOMEM;
852 
853 	data = iio_priv(indio_dev);
854 	dev_set_drvdata(dev, indio_dev);
855 	data->regmap = regmap;
856 	data->irq = irq;
857 	data->dev = dev;
858 
859 	data->regulators[0].supply = "vdd";
860 	data->regulators[1].supply = "vddio";
861 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
862 				      data->regulators);
863 	if (ret)
864 		return dev_err_probe(dev, ret, "failed to get regulators\n");
865 
866 	ret = iio_read_mount_matrix(dev, &data->orientation);
867 	if (ret)
868 		return ret;
869 
870 	mutex_init(&data->mutex);
871 
872 	ret = bmc150_magn_init(data);
873 	if (ret < 0)
874 		return ret;
875 
876 	indio_dev->channels = bmc150_magn_channels;
877 	indio_dev->num_channels = ARRAY_SIZE(bmc150_magn_channels);
878 	indio_dev->available_scan_masks = bmc150_magn_scan_masks;
879 	indio_dev->name = name;
880 	indio_dev->modes = INDIO_DIRECT_MODE;
881 	indio_dev->info = &bmc150_magn_info;
882 
883 	if (irq > 0) {
884 		data->dready_trig = devm_iio_trigger_alloc(dev,
885 							   "%s-dev%d",
886 							   indio_dev->name,
887 							   iio_device_id(indio_dev));
888 		if (!data->dready_trig) {
889 			ret = -ENOMEM;
890 			dev_err(dev, "iio trigger alloc failed\n");
891 			goto err_poweroff;
892 		}
893 
894 		data->dready_trig->ops = &bmc150_magn_trigger_ops;
895 		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
896 		ret = iio_trigger_register(data->dready_trig);
897 		if (ret) {
898 			dev_err(dev, "iio trigger register failed\n");
899 			goto err_poweroff;
900 		}
901 
902 		ret = request_irq(irq, iio_trigger_generic_data_rdy_poll,
903 				  IRQF_TRIGGER_RISING | IRQF_NO_THREAD,
904 				  "bmc150_magn_event", data->dready_trig);
905 		if (ret < 0) {
906 			dev_err(dev, "request irq %d failed\n", irq);
907 			goto err_trigger_unregister;
908 		}
909 	}
910 
911 	ret = iio_triggered_buffer_setup(indio_dev,
912 					 iio_pollfunc_store_time,
913 					 bmc150_magn_trigger_handler,
914 					 &bmc150_magn_buffer_setup_ops);
915 	if (ret < 0) {
916 		dev_err(dev, "iio triggered buffer setup failed\n");
917 		goto err_free_irq;
918 	}
919 
920 	ret = pm_runtime_set_active(dev);
921 	if (ret)
922 		goto err_buffer_cleanup;
923 
924 	pm_runtime_enable(dev);
925 	pm_runtime_set_autosuspend_delay(dev,
926 					 BMC150_MAGN_AUTO_SUSPEND_DELAY_MS);
927 	pm_runtime_use_autosuspend(dev);
928 
929 	ret = iio_device_register(indio_dev);
930 	if (ret < 0) {
931 		dev_err(dev, "unable to register iio device\n");
932 		goto err_pm_cleanup;
933 	}
934 
935 	dev_dbg(dev, "Registered device %s\n", name);
936 	return 0;
937 
938 err_pm_cleanup:
939 	pm_runtime_dont_use_autosuspend(dev);
940 	pm_runtime_disable(dev);
941 err_buffer_cleanup:
942 	iio_triggered_buffer_cleanup(indio_dev);
943 err_free_irq:
944 	if (irq > 0)
945 		free_irq(irq, data->dready_trig);
946 err_trigger_unregister:
947 	if (data->dready_trig)
948 		iio_trigger_unregister(data->dready_trig);
949 err_poweroff:
950 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
951 	return ret;
952 }
953 EXPORT_SYMBOL_NS(bmc150_magn_probe, "IIO_BMC150_MAGN");
954 
bmc150_magn_remove(struct device * dev)955 void bmc150_magn_remove(struct device *dev)
956 {
957 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
958 	struct bmc150_magn_data *data = iio_priv(indio_dev);
959 
960 	iio_device_unregister(indio_dev);
961 
962 	pm_runtime_disable(dev);
963 	pm_runtime_set_suspended(dev);
964 
965 	iio_triggered_buffer_cleanup(indio_dev);
966 
967 	if (data->irq > 0)
968 		free_irq(data->irq, data->dready_trig);
969 
970 	if (data->dready_trig)
971 		iio_trigger_unregister(data->dready_trig);
972 
973 	bmc150_magn_set_power_mode_locked(data, BMC150_MAGN_POWER_MODE_SUSPEND);
974 
975 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
976 }
977 EXPORT_SYMBOL_NS(bmc150_magn_remove, "IIO_BMC150_MAGN");
978 
979 #ifdef CONFIG_PM
bmc150_magn_runtime_suspend(struct device * dev)980 static int bmc150_magn_runtime_suspend(struct device *dev)
981 {
982 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
983 	struct bmc150_magn_data *data = iio_priv(indio_dev);
984 	int ret;
985 
986 	ret = bmc150_magn_set_power_mode_locked(data,
987 						BMC150_MAGN_POWER_MODE_SLEEP);
988 	if (ret < 0) {
989 		dev_err(dev, "powering off device failed\n");
990 		return ret;
991 	}
992 	return 0;
993 }
994 
995 /*
996  * Should be called with data->mutex held.
997  */
bmc150_magn_runtime_resume(struct device * dev)998 static int bmc150_magn_runtime_resume(struct device *dev)
999 {
1000 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1001 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1002 
1003 	return bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
1004 					  true);
1005 }
1006 #endif
1007 
1008 #ifdef CONFIG_PM_SLEEP
bmc150_magn_suspend(struct device * dev)1009 static int bmc150_magn_suspend(struct device *dev)
1010 {
1011 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1012 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1013 
1014 	return bmc150_magn_set_power_mode_locked(data,
1015 						 BMC150_MAGN_POWER_MODE_SLEEP);
1016 }
1017 
bmc150_magn_resume(struct device * dev)1018 static int bmc150_magn_resume(struct device *dev)
1019 {
1020 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1021 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1022 
1023 	return bmc150_magn_set_power_mode_locked(data,
1024 						 BMC150_MAGN_POWER_MODE_NORMAL);
1025 }
1026 #endif
1027 
1028 const struct dev_pm_ops bmc150_magn_pm_ops = {
1029 	SET_SYSTEM_SLEEP_PM_OPS(bmc150_magn_suspend, bmc150_magn_resume)
1030 	SET_RUNTIME_PM_OPS(bmc150_magn_runtime_suspend,
1031 			   bmc150_magn_runtime_resume, NULL)
1032 };
1033 EXPORT_SYMBOL_NS(bmc150_magn_pm_ops, "IIO_BMC150_MAGN");
1034 
1035 MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
1036 MODULE_LICENSE("GPL v2");
1037 MODULE_DESCRIPTION("BMC150 magnetometer core driver");
1038