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/delay.h>
16 #include <linux/slab.h>
17 #include <linux/acpi.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_DRV_NAME			"bmc150_magn"
33 #define BMC150_MAGN_IRQ_NAME			"bmc150_magn_event"
34 
35 #define BMC150_MAGN_REG_CHIP_ID			0x40
36 #define BMC150_MAGN_CHIP_ID_VAL			0x32
37 
38 #define BMC150_MAGN_REG_X_L			0x42
39 #define BMC150_MAGN_REG_X_M			0x43
40 #define BMC150_MAGN_REG_Y_L			0x44
41 #define BMC150_MAGN_REG_Y_M			0x45
42 #define BMC150_MAGN_SHIFT_XY_L			3
43 #define BMC150_MAGN_REG_Z_L			0x46
44 #define BMC150_MAGN_REG_Z_M			0x47
45 #define BMC150_MAGN_SHIFT_Z_L			1
46 #define BMC150_MAGN_REG_RHALL_L			0x48
47 #define BMC150_MAGN_REG_RHALL_M			0x49
48 #define BMC150_MAGN_SHIFT_RHALL_L		2
49 
50 #define BMC150_MAGN_REG_INT_STATUS		0x4A
51 
52 #define BMC150_MAGN_REG_POWER			0x4B
53 #define BMC150_MAGN_MASK_POWER_CTL		BIT(0)
54 
55 #define BMC150_MAGN_REG_OPMODE_ODR		0x4C
56 #define BMC150_MAGN_MASK_OPMODE			GENMASK(2, 1)
57 #define BMC150_MAGN_SHIFT_OPMODE		1
58 #define BMC150_MAGN_MODE_NORMAL			0x00
59 #define BMC150_MAGN_MODE_FORCED			0x01
60 #define BMC150_MAGN_MODE_SLEEP			0x03
61 #define BMC150_MAGN_MASK_ODR			GENMASK(5, 3)
62 #define BMC150_MAGN_SHIFT_ODR			3
63 
64 #define BMC150_MAGN_REG_INT			0x4D
65 
66 #define BMC150_MAGN_REG_INT_DRDY		0x4E
67 #define BMC150_MAGN_MASK_DRDY_EN		BIT(7)
68 #define BMC150_MAGN_SHIFT_DRDY_EN		7
69 #define BMC150_MAGN_MASK_DRDY_INT3		BIT(6)
70 #define BMC150_MAGN_MASK_DRDY_Z_EN		BIT(5)
71 #define BMC150_MAGN_MASK_DRDY_Y_EN		BIT(4)
72 #define BMC150_MAGN_MASK_DRDY_X_EN		BIT(3)
73 #define BMC150_MAGN_MASK_DRDY_DR_POLARITY	BIT(2)
74 #define BMC150_MAGN_MASK_DRDY_LATCHING		BIT(1)
75 #define BMC150_MAGN_MASK_DRDY_INT3_POLARITY	BIT(0)
76 
77 #define BMC150_MAGN_REG_LOW_THRESH		0x4F
78 #define BMC150_MAGN_REG_HIGH_THRESH		0x50
79 #define BMC150_MAGN_REG_REP_XY			0x51
80 #define BMC150_MAGN_REG_REP_Z			0x52
81 #define BMC150_MAGN_REG_REP_DATAMASK		GENMASK(7, 0)
82 
83 #define BMC150_MAGN_REG_TRIM_START		0x5D
84 #define BMC150_MAGN_REG_TRIM_END		0x71
85 
86 #define BMC150_MAGN_XY_OVERFLOW_VAL		-4096
87 #define BMC150_MAGN_Z_OVERFLOW_VAL		-16384
88 
89 /* Time from SUSPEND to SLEEP */
90 #define BMC150_MAGN_START_UP_TIME_MS		3
91 
92 #define BMC150_MAGN_AUTO_SUSPEND_DELAY_MS	2000
93 
94 #define BMC150_MAGN_REGVAL_TO_REPXY(regval) (((regval) * 2) + 1)
95 #define BMC150_MAGN_REGVAL_TO_REPZ(regval) ((regval) + 1)
96 #define BMC150_MAGN_REPXY_TO_REGVAL(rep) (((rep) - 1) / 2)
97 #define BMC150_MAGN_REPZ_TO_REGVAL(rep) ((rep) - 1)
98 
99 enum bmc150_magn_axis {
100 	AXIS_X,
101 	AXIS_Y,
102 	AXIS_Z,
103 	RHALL,
104 	AXIS_XYZ_MAX = RHALL,
105 	AXIS_XYZR_MAX,
106 };
107 
108 enum bmc150_magn_power_modes {
109 	BMC150_MAGN_POWER_MODE_SUSPEND,
110 	BMC150_MAGN_POWER_MODE_SLEEP,
111 	BMC150_MAGN_POWER_MODE_NORMAL,
112 };
113 
114 struct bmc150_magn_trim_regs {
115 	s8 x1;
116 	s8 y1;
117 	__le16 reserved1;
118 	u8 reserved2;
119 	__le16 z4;
120 	s8 x2;
121 	s8 y2;
122 	__le16 reserved3;
123 	__le16 z2;
124 	__le16 z1;
125 	__le16 xyz1;
126 	__le16 z3;
127 	s8 xy2;
128 	u8 xy1;
129 } __packed;
130 
131 struct bmc150_magn_data {
132 	struct device *dev;
133 	/*
134 	 * 1. Protect this structure.
135 	 * 2. Serialize sequences that power on/off the device and access HW.
136 	 */
137 	struct mutex mutex;
138 	struct regmap *regmap;
139 	struct regulator_bulk_data regulators[2];
140 	struct iio_mount_matrix orientation;
141 	/* Ensure timestamp is naturally aligned */
142 	struct {
143 		s32 chans[3];
144 		s64 timestamp __aligned(8);
145 	} scan;
146 	struct iio_trigger *dready_trig;
147 	bool dready_trigger_on;
148 	int max_odr;
149 	int irq;
150 };
151 
152 static const struct {
153 	int freq;
154 	u8 reg_val;
155 } bmc150_magn_samp_freq_table[] = { {2, 0x01},
156 				    {6, 0x02},
157 				    {8, 0x03},
158 				    {10, 0x00},
159 				    {15, 0x04},
160 				    {20, 0x05},
161 				    {25, 0x06},
162 				    {30, 0x07} };
163 
164 enum bmc150_magn_presets {
165 	LOW_POWER_PRESET,
166 	REGULAR_PRESET,
167 	ENHANCED_REGULAR_PRESET,
168 	HIGH_ACCURACY_PRESET
169 };
170 
171 static const struct bmc150_magn_preset {
172 	u8 rep_xy;
173 	u8 rep_z;
174 	u8 odr;
175 } bmc150_magn_presets_table[] = {
176 	[LOW_POWER_PRESET] = {3, 3, 10},
177 	[REGULAR_PRESET] =  {9, 15, 10},
178 	[ENHANCED_REGULAR_PRESET] =  {15, 27, 10},
179 	[HIGH_ACCURACY_PRESET] =  {47, 83, 20},
180 };
181 
182 #define BMC150_MAGN_DEFAULT_PRESET REGULAR_PRESET
183 
bmc150_magn_is_writeable_reg(struct device * dev,unsigned int reg)184 static bool bmc150_magn_is_writeable_reg(struct device *dev, unsigned int reg)
185 {
186 	switch (reg) {
187 	case BMC150_MAGN_REG_POWER:
188 	case BMC150_MAGN_REG_OPMODE_ODR:
189 	case BMC150_MAGN_REG_INT:
190 	case BMC150_MAGN_REG_INT_DRDY:
191 	case BMC150_MAGN_REG_LOW_THRESH:
192 	case BMC150_MAGN_REG_HIGH_THRESH:
193 	case BMC150_MAGN_REG_REP_XY:
194 	case BMC150_MAGN_REG_REP_Z:
195 		return true;
196 	default:
197 		return false;
198 	}
199 }
200 
bmc150_magn_is_volatile_reg(struct device * dev,unsigned int reg)201 static bool bmc150_magn_is_volatile_reg(struct device *dev, unsigned int reg)
202 {
203 	switch (reg) {
204 	case BMC150_MAGN_REG_X_L:
205 	case BMC150_MAGN_REG_X_M:
206 	case BMC150_MAGN_REG_Y_L:
207 	case BMC150_MAGN_REG_Y_M:
208 	case BMC150_MAGN_REG_Z_L:
209 	case BMC150_MAGN_REG_Z_M:
210 	case BMC150_MAGN_REG_RHALL_L:
211 	case BMC150_MAGN_REG_RHALL_M:
212 	case BMC150_MAGN_REG_INT_STATUS:
213 		return true;
214 	default:
215 		return false;
216 	}
217 }
218 
219 const struct regmap_config bmc150_magn_regmap_config = {
220 	.reg_bits = 8,
221 	.val_bits = 8,
222 
223 	.max_register = BMC150_MAGN_REG_TRIM_END,
224 	.cache_type = REGCACHE_RBTREE,
225 
226 	.writeable_reg = bmc150_magn_is_writeable_reg,
227 	.volatile_reg = bmc150_magn_is_volatile_reg,
228 };
229 EXPORT_SYMBOL(bmc150_magn_regmap_config);
230 
bmc150_magn_set_power_mode(struct bmc150_magn_data * data,enum bmc150_magn_power_modes mode,bool state)231 static int bmc150_magn_set_power_mode(struct bmc150_magn_data *data,
232 				      enum bmc150_magn_power_modes mode,
233 				      bool state)
234 {
235 	int ret;
236 
237 	switch (mode) {
238 	case BMC150_MAGN_POWER_MODE_SUSPEND:
239 		ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_POWER,
240 					 BMC150_MAGN_MASK_POWER_CTL, !state);
241 		if (ret < 0)
242 			return ret;
243 		usleep_range(BMC150_MAGN_START_UP_TIME_MS * 1000, 20000);
244 		return 0;
245 	case BMC150_MAGN_POWER_MODE_SLEEP:
246 		return regmap_update_bits(data->regmap,
247 					  BMC150_MAGN_REG_OPMODE_ODR,
248 					  BMC150_MAGN_MASK_OPMODE,
249 					  BMC150_MAGN_MODE_SLEEP <<
250 					  BMC150_MAGN_SHIFT_OPMODE);
251 	case BMC150_MAGN_POWER_MODE_NORMAL:
252 		return regmap_update_bits(data->regmap,
253 					  BMC150_MAGN_REG_OPMODE_ODR,
254 					  BMC150_MAGN_MASK_OPMODE,
255 					  BMC150_MAGN_MODE_NORMAL <<
256 					  BMC150_MAGN_SHIFT_OPMODE);
257 	}
258 
259 	return -EINVAL;
260 }
261 
bmc150_magn_set_power_state(struct bmc150_magn_data * data,bool on)262 static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
263 {
264 #ifdef CONFIG_PM
265 	int ret;
266 
267 	if (on) {
268 		ret = pm_runtime_resume_and_get(data->dev);
269 	} else {
270 		pm_runtime_mark_last_busy(data->dev);
271 		ret = pm_runtime_put_autosuspend(data->dev);
272 	}
273 
274 	if (ret < 0) {
275 		dev_err(data->dev,
276 			"failed to change power state to %d\n", on);
277 		return ret;
278 	}
279 #endif
280 
281 	return 0;
282 }
283 
bmc150_magn_get_odr(struct bmc150_magn_data * data,int * val)284 static int bmc150_magn_get_odr(struct bmc150_magn_data *data, int *val)
285 {
286 	int ret, reg_val;
287 	u8 i, odr_val;
288 
289 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_OPMODE_ODR, &reg_val);
290 	if (ret < 0)
291 		return ret;
292 	odr_val = (reg_val & BMC150_MAGN_MASK_ODR) >> BMC150_MAGN_SHIFT_ODR;
293 
294 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++)
295 		if (bmc150_magn_samp_freq_table[i].reg_val == odr_val) {
296 			*val = bmc150_magn_samp_freq_table[i].freq;
297 			return 0;
298 		}
299 
300 	return -EINVAL;
301 }
302 
bmc150_magn_set_odr(struct bmc150_magn_data * data,int val)303 static int bmc150_magn_set_odr(struct bmc150_magn_data *data, int val)
304 {
305 	int ret;
306 	u8 i;
307 
308 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
309 		if (bmc150_magn_samp_freq_table[i].freq == val) {
310 			ret = regmap_update_bits(data->regmap,
311 						 BMC150_MAGN_REG_OPMODE_ODR,
312 						 BMC150_MAGN_MASK_ODR,
313 						 bmc150_magn_samp_freq_table[i].
314 						 reg_val <<
315 						 BMC150_MAGN_SHIFT_ODR);
316 			if (ret < 0)
317 				return ret;
318 			return 0;
319 		}
320 	}
321 
322 	return -EINVAL;
323 }
324 
bmc150_magn_set_max_odr(struct bmc150_magn_data * data,int rep_xy,int rep_z,int odr)325 static int bmc150_magn_set_max_odr(struct bmc150_magn_data *data, int rep_xy,
326 				   int rep_z, int odr)
327 {
328 	int ret, reg_val, max_odr;
329 
330 	if (rep_xy <= 0) {
331 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
332 				  &reg_val);
333 		if (ret < 0)
334 			return ret;
335 		rep_xy = BMC150_MAGN_REGVAL_TO_REPXY(reg_val);
336 	}
337 	if (rep_z <= 0) {
338 		ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
339 				  &reg_val);
340 		if (ret < 0)
341 			return ret;
342 		rep_z = BMC150_MAGN_REGVAL_TO_REPZ(reg_val);
343 	}
344 	if (odr <= 0) {
345 		ret = bmc150_magn_get_odr(data, &odr);
346 		if (ret < 0)
347 			return ret;
348 	}
349 	/* the maximum selectable read-out frequency from datasheet */
350 	max_odr = 1000000 / (145 * rep_xy + 500 * rep_z + 980);
351 	if (odr > max_odr) {
352 		dev_err(data->dev,
353 			"Can't set oversampling with sampling freq %d\n",
354 			odr);
355 		return -EINVAL;
356 	}
357 	data->max_odr = max_odr;
358 
359 	return 0;
360 }
361 
bmc150_magn_compensate_x(struct bmc150_magn_trim_regs * tregs,s16 x,u16 rhall)362 static s32 bmc150_magn_compensate_x(struct bmc150_magn_trim_regs *tregs, s16 x,
363 				    u16 rhall)
364 {
365 	s16 val;
366 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
367 
368 	if (x == BMC150_MAGN_XY_OVERFLOW_VAL)
369 		return S32_MIN;
370 
371 	if (!rhall)
372 		rhall = xyz1;
373 
374 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
375 	val = ((s16)((((s32)x) * ((((((((s32)tregs->xy2) * ((((s32)val) *
376 	      ((s32)val)) >> 7)) + (((s32)val) *
377 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
378 	      ((s32)(((s16)tregs->x2) + ((s16)0xA0)))) >> 12)) >> 13)) +
379 	      (((s16)tregs->x1) << 3);
380 
381 	return (s32)val;
382 }
383 
bmc150_magn_compensate_y(struct bmc150_magn_trim_regs * tregs,s16 y,u16 rhall)384 static s32 bmc150_magn_compensate_y(struct bmc150_magn_trim_regs *tregs, s16 y,
385 				    u16 rhall)
386 {
387 	s16 val;
388 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
389 
390 	if (y == BMC150_MAGN_XY_OVERFLOW_VAL)
391 		return S32_MIN;
392 
393 	if (!rhall)
394 		rhall = xyz1;
395 
396 	val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
397 	val = ((s16)((((s32)y) * ((((((((s32)tregs->xy2) * ((((s32)val) *
398 	      ((s32)val)) >> 7)) + (((s32)val) *
399 	      ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
400 	      ((s32)(((s16)tregs->y2) + ((s16)0xA0)))) >> 12)) >> 13)) +
401 	      (((s16)tregs->y1) << 3);
402 
403 	return (s32)val;
404 }
405 
bmc150_magn_compensate_z(struct bmc150_magn_trim_regs * tregs,s16 z,u16 rhall)406 static s32 bmc150_magn_compensate_z(struct bmc150_magn_trim_regs *tregs, s16 z,
407 				    u16 rhall)
408 {
409 	s32 val;
410 	u16 xyz1 = le16_to_cpu(tregs->xyz1);
411 	u16 z1 = le16_to_cpu(tregs->z1);
412 	s16 z2 = le16_to_cpu(tregs->z2);
413 	s16 z3 = le16_to_cpu(tregs->z3);
414 	s16 z4 = le16_to_cpu(tregs->z4);
415 
416 	if (z == BMC150_MAGN_Z_OVERFLOW_VAL)
417 		return S32_MIN;
418 
419 	val = (((((s32)(z - z4)) << 15) - ((((s32)z3) * ((s32)(((s16)rhall) -
420 	      ((s16)xyz1)))) >> 2)) / (z2 + ((s16)(((((s32)z1) *
421 	      ((((s16)rhall) << 1))) + (1 << 15)) >> 16))));
422 
423 	return val;
424 }
425 
bmc150_magn_read_xyz(struct bmc150_magn_data * data,s32 * buffer)426 static int bmc150_magn_read_xyz(struct bmc150_magn_data *data, s32 *buffer)
427 {
428 	int ret;
429 	__le16 values[AXIS_XYZR_MAX];
430 	s16 raw_x, raw_y, raw_z;
431 	u16 rhall;
432 	struct bmc150_magn_trim_regs tregs;
433 
434 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_X_L,
435 			       values, sizeof(values));
436 	if (ret < 0)
437 		return ret;
438 
439 	raw_x = (s16)le16_to_cpu(values[AXIS_X]) >> BMC150_MAGN_SHIFT_XY_L;
440 	raw_y = (s16)le16_to_cpu(values[AXIS_Y]) >> BMC150_MAGN_SHIFT_XY_L;
441 	raw_z = (s16)le16_to_cpu(values[AXIS_Z]) >> BMC150_MAGN_SHIFT_Z_L;
442 	rhall = le16_to_cpu(values[RHALL]) >> BMC150_MAGN_SHIFT_RHALL_L;
443 
444 	ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_TRIM_START,
445 			       &tregs, sizeof(tregs));
446 	if (ret < 0)
447 		return ret;
448 
449 	buffer[AXIS_X] = bmc150_magn_compensate_x(&tregs, raw_x, rhall);
450 	buffer[AXIS_Y] = bmc150_magn_compensate_y(&tregs, raw_y, rhall);
451 	buffer[AXIS_Z] = bmc150_magn_compensate_z(&tregs, raw_z, rhall);
452 
453 	return 0;
454 }
455 
bmc150_magn_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)456 static int bmc150_magn_read_raw(struct iio_dev *indio_dev,
457 				struct iio_chan_spec const *chan,
458 				int *val, int *val2, long mask)
459 {
460 	struct bmc150_magn_data *data = iio_priv(indio_dev);
461 	int ret, tmp;
462 	s32 values[AXIS_XYZ_MAX];
463 
464 	switch (mask) {
465 	case IIO_CHAN_INFO_RAW:
466 		if (iio_buffer_enabled(indio_dev))
467 			return -EBUSY;
468 		mutex_lock(&data->mutex);
469 
470 		ret = bmc150_magn_set_power_state(data, true);
471 		if (ret < 0) {
472 			mutex_unlock(&data->mutex);
473 			return ret;
474 		}
475 
476 		ret = bmc150_magn_read_xyz(data, values);
477 		if (ret < 0) {
478 			bmc150_magn_set_power_state(data, false);
479 			mutex_unlock(&data->mutex);
480 			return ret;
481 		}
482 		*val = values[chan->scan_index];
483 
484 		ret = bmc150_magn_set_power_state(data, false);
485 		if (ret < 0) {
486 			mutex_unlock(&data->mutex);
487 			return ret;
488 		}
489 
490 		mutex_unlock(&data->mutex);
491 		return IIO_VAL_INT;
492 	case IIO_CHAN_INFO_SCALE:
493 		/*
494 		 * The API/driver performs an off-chip temperature
495 		 * compensation and outputs x/y/z magnetic field data in
496 		 * 16 LSB/uT to the upper application layer.
497 		 */
498 		*val = 0;
499 		*val2 = 625;
500 		return IIO_VAL_INT_PLUS_MICRO;
501 	case IIO_CHAN_INFO_SAMP_FREQ:
502 		ret = bmc150_magn_get_odr(data, val);
503 		if (ret < 0)
504 			return ret;
505 		return IIO_VAL_INT;
506 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
507 		switch (chan->channel2) {
508 		case IIO_MOD_X:
509 		case IIO_MOD_Y:
510 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
511 					  &tmp);
512 			if (ret < 0)
513 				return ret;
514 			*val = BMC150_MAGN_REGVAL_TO_REPXY(tmp);
515 			return IIO_VAL_INT;
516 		case IIO_MOD_Z:
517 			ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
518 					  &tmp);
519 			if (ret < 0)
520 				return ret;
521 			*val = BMC150_MAGN_REGVAL_TO_REPZ(tmp);
522 			return IIO_VAL_INT;
523 		default:
524 			return -EINVAL;
525 		}
526 	default:
527 		return -EINVAL;
528 	}
529 }
530 
bmc150_magn_write_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int val,int val2,long mask)531 static int bmc150_magn_write_raw(struct iio_dev *indio_dev,
532 				 struct iio_chan_spec const *chan,
533 				 int val, int val2, long mask)
534 {
535 	struct bmc150_magn_data *data = iio_priv(indio_dev);
536 	int ret;
537 
538 	switch (mask) {
539 	case IIO_CHAN_INFO_SAMP_FREQ:
540 		if (val > data->max_odr)
541 			return -EINVAL;
542 		mutex_lock(&data->mutex);
543 		ret = bmc150_magn_set_odr(data, val);
544 		mutex_unlock(&data->mutex);
545 		return ret;
546 	case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
547 		switch (chan->channel2) {
548 		case IIO_MOD_X:
549 		case IIO_MOD_Y:
550 			if (val < 1 || val > 511)
551 				return -EINVAL;
552 			mutex_lock(&data->mutex);
553 			ret = bmc150_magn_set_max_odr(data, val, 0, 0);
554 			if (ret < 0) {
555 				mutex_unlock(&data->mutex);
556 				return ret;
557 			}
558 			ret = regmap_update_bits(data->regmap,
559 						 BMC150_MAGN_REG_REP_XY,
560 						 BMC150_MAGN_REG_REP_DATAMASK,
561 						 BMC150_MAGN_REPXY_TO_REGVAL
562 						 (val));
563 			mutex_unlock(&data->mutex);
564 			return ret;
565 		case IIO_MOD_Z:
566 			if (val < 1 || val > 256)
567 				return -EINVAL;
568 			mutex_lock(&data->mutex);
569 			ret = bmc150_magn_set_max_odr(data, 0, val, 0);
570 			if (ret < 0) {
571 				mutex_unlock(&data->mutex);
572 				return ret;
573 			}
574 			ret = regmap_update_bits(data->regmap,
575 						 BMC150_MAGN_REG_REP_Z,
576 						 BMC150_MAGN_REG_REP_DATAMASK,
577 						 BMC150_MAGN_REPZ_TO_REGVAL
578 						 (val));
579 			mutex_unlock(&data->mutex);
580 			return ret;
581 		default:
582 			return -EINVAL;
583 		}
584 	default:
585 		return -EINVAL;
586 	}
587 }
588 
bmc150_magn_show_samp_freq_avail(struct device * dev,struct device_attribute * attr,char * buf)589 static ssize_t bmc150_magn_show_samp_freq_avail(struct device *dev,
590 						struct device_attribute *attr,
591 						char *buf)
592 {
593 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
594 	struct bmc150_magn_data *data = iio_priv(indio_dev);
595 	size_t len = 0;
596 	u8 i;
597 
598 	for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
599 		if (bmc150_magn_samp_freq_table[i].freq > data->max_odr)
600 			break;
601 		len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
602 				 bmc150_magn_samp_freq_table[i].freq);
603 	}
604 	/* replace last space with a newline */
605 	buf[len - 1] = '\n';
606 
607 	return len;
608 }
609 
610 static const struct iio_mount_matrix *
bmc150_magn_get_mount_matrix(const struct iio_dev * indio_dev,const struct iio_chan_spec * chan)611 bmc150_magn_get_mount_matrix(const struct iio_dev *indio_dev,
612 			      const struct iio_chan_spec *chan)
613 {
614 	struct bmc150_magn_data *data = iio_priv(indio_dev);
615 
616 	return &data->orientation;
617 }
618 
619 static const struct iio_chan_spec_ext_info bmc150_magn_ext_info[] = {
620 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, bmc150_magn_get_mount_matrix),
621 	{ }
622 };
623 
624 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(bmc150_magn_show_samp_freq_avail);
625 
626 static struct attribute *bmc150_magn_attributes[] = {
627 	&iio_dev_attr_sampling_frequency_available.dev_attr.attr,
628 	NULL,
629 };
630 
631 static const struct attribute_group bmc150_magn_attrs_group = {
632 	.attrs = bmc150_magn_attributes,
633 };
634 
635 #define BMC150_MAGN_CHANNEL(_axis) {					\
636 	.type = IIO_MAGN,						\
637 	.modified = 1,							\
638 	.channel2 = IIO_MOD_##_axis,					\
639 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |			\
640 			      BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),	\
641 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |	\
642 				    BIT(IIO_CHAN_INFO_SCALE),		\
643 	.scan_index = AXIS_##_axis,					\
644 	.scan_type = {							\
645 		.sign = 's',						\
646 		.realbits = 32,						\
647 		.storagebits = 32,					\
648 		.endianness = IIO_LE					\
649 	},								\
650 	.ext_info = bmc150_magn_ext_info,				\
651 }
652 
653 static const struct iio_chan_spec bmc150_magn_channels[] = {
654 	BMC150_MAGN_CHANNEL(X),
655 	BMC150_MAGN_CHANNEL(Y),
656 	BMC150_MAGN_CHANNEL(Z),
657 	IIO_CHAN_SOFT_TIMESTAMP(3),
658 };
659 
660 static const struct iio_info bmc150_magn_info = {
661 	.attrs = &bmc150_magn_attrs_group,
662 	.read_raw = bmc150_magn_read_raw,
663 	.write_raw = bmc150_magn_write_raw,
664 };
665 
666 static const unsigned long bmc150_magn_scan_masks[] = {
667 					BIT(AXIS_X) | BIT(AXIS_Y) | BIT(AXIS_Z),
668 					0};
669 
bmc150_magn_trigger_handler(int irq,void * p)670 static irqreturn_t bmc150_magn_trigger_handler(int irq, void *p)
671 {
672 	struct iio_poll_func *pf = p;
673 	struct iio_dev *indio_dev = pf->indio_dev;
674 	struct bmc150_magn_data *data = iio_priv(indio_dev);
675 	int ret;
676 
677 	mutex_lock(&data->mutex);
678 	ret = bmc150_magn_read_xyz(data, data->scan.chans);
679 	if (ret < 0)
680 		goto err;
681 
682 	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
683 					   pf->timestamp);
684 
685 err:
686 	mutex_unlock(&data->mutex);
687 	iio_trigger_notify_done(indio_dev->trig);
688 
689 	return IRQ_HANDLED;
690 }
691 
bmc150_magn_init(struct bmc150_magn_data * data)692 static int bmc150_magn_init(struct bmc150_magn_data *data)
693 {
694 	int ret, chip_id;
695 	struct bmc150_magn_preset preset;
696 
697 	ret = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
698 				    data->regulators);
699 	if (ret < 0) {
700 		dev_err(data->dev, "Failed to enable regulators: %d\n", ret);
701 		return ret;
702 	}
703 	/*
704 	 * 3ms power-on time according to datasheet, let's better
705 	 * be safe than sorry and set this delay to 5ms.
706 	 */
707 	msleep(5);
708 
709 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND,
710 					 false);
711 	if (ret < 0) {
712 		dev_err(data->dev,
713 			"Failed to bring up device from suspend mode\n");
714 		goto err_regulator_disable;
715 	}
716 
717 	ret = regmap_read(data->regmap, BMC150_MAGN_REG_CHIP_ID, &chip_id);
718 	if (ret < 0) {
719 		dev_err(data->dev, "Failed reading chip id\n");
720 		goto err_poweroff;
721 	}
722 	if (chip_id != BMC150_MAGN_CHIP_ID_VAL) {
723 		dev_err(data->dev, "Invalid chip id 0x%x\n", chip_id);
724 		ret = -ENODEV;
725 		goto err_poweroff;
726 	}
727 	dev_dbg(data->dev, "Chip id %x\n", chip_id);
728 
729 	preset = bmc150_magn_presets_table[BMC150_MAGN_DEFAULT_PRESET];
730 	ret = bmc150_magn_set_odr(data, preset.odr);
731 	if (ret < 0) {
732 		dev_err(data->dev, "Failed to set ODR to %d\n",
733 			preset.odr);
734 		goto err_poweroff;
735 	}
736 
737 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_XY,
738 			   BMC150_MAGN_REPXY_TO_REGVAL(preset.rep_xy));
739 	if (ret < 0) {
740 		dev_err(data->dev, "Failed to set REP XY to %d\n",
741 			preset.rep_xy);
742 		goto err_poweroff;
743 	}
744 
745 	ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_Z,
746 			   BMC150_MAGN_REPZ_TO_REGVAL(preset.rep_z));
747 	if (ret < 0) {
748 		dev_err(data->dev, "Failed to set REP Z to %d\n",
749 			preset.rep_z);
750 		goto err_poweroff;
751 	}
752 
753 	ret = bmc150_magn_set_max_odr(data, preset.rep_xy, preset.rep_z,
754 				      preset.odr);
755 	if (ret < 0)
756 		goto err_poweroff;
757 
758 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
759 					 true);
760 	if (ret < 0) {
761 		dev_err(data->dev, "Failed to power on device\n");
762 		goto err_poweroff;
763 	}
764 
765 	return 0;
766 
767 err_poweroff:
768 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
769 err_regulator_disable:
770 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
771 	return ret;
772 }
773 
bmc150_magn_reset_intr(struct bmc150_magn_data * data)774 static int bmc150_magn_reset_intr(struct bmc150_magn_data *data)
775 {
776 	int tmp;
777 
778 	/*
779 	 * Data Ready (DRDY) is always cleared after
780 	 * readout of data registers ends.
781 	 */
782 	return regmap_read(data->regmap, BMC150_MAGN_REG_X_L, &tmp);
783 }
784 
bmc150_magn_trig_reen(struct iio_trigger * trig)785 static void bmc150_magn_trig_reen(struct iio_trigger *trig)
786 {
787 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
788 	struct bmc150_magn_data *data = iio_priv(indio_dev);
789 	int ret;
790 
791 	if (!data->dready_trigger_on)
792 		return;
793 
794 	mutex_lock(&data->mutex);
795 	ret = bmc150_magn_reset_intr(data);
796 	mutex_unlock(&data->mutex);
797 	if (ret)
798 		dev_err(data->dev, "Failed to reset interrupt\n");
799 }
800 
bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger * trig,bool state)801 static int bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger *trig,
802 						  bool state)
803 {
804 	struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
805 	struct bmc150_magn_data *data = iio_priv(indio_dev);
806 	int ret = 0;
807 
808 	mutex_lock(&data->mutex);
809 	if (state == data->dready_trigger_on)
810 		goto err_unlock;
811 
812 	ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_INT_DRDY,
813 				 BMC150_MAGN_MASK_DRDY_EN,
814 				 state << BMC150_MAGN_SHIFT_DRDY_EN);
815 	if (ret < 0)
816 		goto err_unlock;
817 
818 	data->dready_trigger_on = state;
819 
820 	if (state) {
821 		ret = bmc150_magn_reset_intr(data);
822 		if (ret < 0)
823 			goto err_unlock;
824 	}
825 	mutex_unlock(&data->mutex);
826 
827 	return 0;
828 
829 err_unlock:
830 	mutex_unlock(&data->mutex);
831 	return ret;
832 }
833 
834 static const struct iio_trigger_ops bmc150_magn_trigger_ops = {
835 	.set_trigger_state = bmc150_magn_data_rdy_trigger_set_state,
836 	.reenable = bmc150_magn_trig_reen,
837 };
838 
bmc150_magn_buffer_preenable(struct iio_dev * indio_dev)839 static int bmc150_magn_buffer_preenable(struct iio_dev *indio_dev)
840 {
841 	struct bmc150_magn_data *data = iio_priv(indio_dev);
842 
843 	return bmc150_magn_set_power_state(data, true);
844 }
845 
bmc150_magn_buffer_postdisable(struct iio_dev * indio_dev)846 static int bmc150_magn_buffer_postdisable(struct iio_dev *indio_dev)
847 {
848 	struct bmc150_magn_data *data = iio_priv(indio_dev);
849 
850 	return bmc150_magn_set_power_state(data, false);
851 }
852 
853 static const struct iio_buffer_setup_ops bmc150_magn_buffer_setup_ops = {
854 	.preenable = bmc150_magn_buffer_preenable,
855 	.postdisable = bmc150_magn_buffer_postdisable,
856 };
857 
bmc150_magn_match_acpi_device(struct device * dev)858 static const char *bmc150_magn_match_acpi_device(struct device *dev)
859 {
860 	const struct acpi_device_id *id;
861 
862 	id = acpi_match_device(dev->driver->acpi_match_table, dev);
863 	if (!id)
864 		return NULL;
865 
866 	return dev_name(dev);
867 }
868 
bmc150_magn_probe(struct device * dev,struct regmap * regmap,int irq,const char * name)869 int bmc150_magn_probe(struct device *dev, struct regmap *regmap,
870 		      int irq, const char *name)
871 {
872 	struct bmc150_magn_data *data;
873 	struct iio_dev *indio_dev;
874 	int ret;
875 
876 	indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
877 	if (!indio_dev)
878 		return -ENOMEM;
879 
880 	data = iio_priv(indio_dev);
881 	dev_set_drvdata(dev, indio_dev);
882 	data->regmap = regmap;
883 	data->irq = irq;
884 	data->dev = dev;
885 
886 	data->regulators[0].supply = "vdd";
887 	data->regulators[1].supply = "vddio";
888 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
889 				      data->regulators);
890 	if (ret)
891 		return dev_err_probe(dev, ret, "failed to get regulators\n");
892 
893 	ret = iio_read_mount_matrix(dev, &data->orientation);
894 	if (ret)
895 		return ret;
896 
897 	if (!name && ACPI_HANDLE(dev))
898 		name = bmc150_magn_match_acpi_device(dev);
899 
900 	mutex_init(&data->mutex);
901 
902 	ret = bmc150_magn_init(data);
903 	if (ret < 0)
904 		return ret;
905 
906 	indio_dev->channels = bmc150_magn_channels;
907 	indio_dev->num_channels = ARRAY_SIZE(bmc150_magn_channels);
908 	indio_dev->available_scan_masks = bmc150_magn_scan_masks;
909 	indio_dev->name = name;
910 	indio_dev->modes = INDIO_DIRECT_MODE;
911 	indio_dev->info = &bmc150_magn_info;
912 
913 	if (irq > 0) {
914 		data->dready_trig = devm_iio_trigger_alloc(dev,
915 							   "%s-dev%d",
916 							   indio_dev->name,
917 							   iio_device_id(indio_dev));
918 		if (!data->dready_trig) {
919 			ret = -ENOMEM;
920 			dev_err(dev, "iio trigger alloc failed\n");
921 			goto err_poweroff;
922 		}
923 
924 		data->dready_trig->ops = &bmc150_magn_trigger_ops;
925 		iio_trigger_set_drvdata(data->dready_trig, indio_dev);
926 		ret = iio_trigger_register(data->dready_trig);
927 		if (ret) {
928 			dev_err(dev, "iio trigger register failed\n");
929 			goto err_poweroff;
930 		}
931 
932 		ret = request_threaded_irq(irq,
933 					   iio_trigger_generic_data_rdy_poll,
934 					   NULL,
935 					   IRQF_TRIGGER_RISING | IRQF_ONESHOT,
936 					   BMC150_MAGN_IRQ_NAME,
937 					   data->dready_trig);
938 		if (ret < 0) {
939 			dev_err(dev, "request irq %d failed\n", irq);
940 			goto err_trigger_unregister;
941 		}
942 	}
943 
944 	ret = iio_triggered_buffer_setup(indio_dev,
945 					 iio_pollfunc_store_time,
946 					 bmc150_magn_trigger_handler,
947 					 &bmc150_magn_buffer_setup_ops);
948 	if (ret < 0) {
949 		dev_err(dev, "iio triggered buffer setup failed\n");
950 		goto err_free_irq;
951 	}
952 
953 	ret = pm_runtime_set_active(dev);
954 	if (ret)
955 		goto err_buffer_cleanup;
956 
957 	pm_runtime_enable(dev);
958 	pm_runtime_set_autosuspend_delay(dev,
959 					 BMC150_MAGN_AUTO_SUSPEND_DELAY_MS);
960 	pm_runtime_use_autosuspend(dev);
961 
962 	ret = iio_device_register(indio_dev);
963 	if (ret < 0) {
964 		dev_err(dev, "unable to register iio device\n");
965 		goto err_disable_runtime_pm;
966 	}
967 
968 	dev_dbg(dev, "Registered device %s\n", name);
969 	return 0;
970 
971 err_disable_runtime_pm:
972 	pm_runtime_disable(dev);
973 err_buffer_cleanup:
974 	iio_triggered_buffer_cleanup(indio_dev);
975 err_free_irq:
976 	if (irq > 0)
977 		free_irq(irq, data->dready_trig);
978 err_trigger_unregister:
979 	if (data->dready_trig)
980 		iio_trigger_unregister(data->dready_trig);
981 err_poweroff:
982 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
983 	return ret;
984 }
985 EXPORT_SYMBOL(bmc150_magn_probe);
986 
bmc150_magn_remove(struct device * dev)987 int bmc150_magn_remove(struct device *dev)
988 {
989 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
990 	struct bmc150_magn_data *data = iio_priv(indio_dev);
991 
992 	iio_device_unregister(indio_dev);
993 
994 	pm_runtime_disable(dev);
995 	pm_runtime_set_suspended(dev);
996 
997 	iio_triggered_buffer_cleanup(indio_dev);
998 
999 	if (data->irq > 0)
1000 		free_irq(data->irq, data->dready_trig);
1001 
1002 	if (data->dready_trig)
1003 		iio_trigger_unregister(data->dready_trig);
1004 
1005 	mutex_lock(&data->mutex);
1006 	bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
1007 	mutex_unlock(&data->mutex);
1008 
1009 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
1010 	return 0;
1011 }
1012 EXPORT_SYMBOL(bmc150_magn_remove);
1013 
1014 #ifdef CONFIG_PM
bmc150_magn_runtime_suspend(struct device * dev)1015 static int bmc150_magn_runtime_suspend(struct device *dev)
1016 {
1017 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1018 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1019 	int ret;
1020 
1021 	mutex_lock(&data->mutex);
1022 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
1023 					 true);
1024 	mutex_unlock(&data->mutex);
1025 	if (ret < 0) {
1026 		dev_err(dev, "powering off device failed\n");
1027 		return ret;
1028 	}
1029 	return 0;
1030 }
1031 
1032 /*
1033  * Should be called with data->mutex held.
1034  */
bmc150_magn_runtime_resume(struct device * dev)1035 static int bmc150_magn_runtime_resume(struct device *dev)
1036 {
1037 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1038 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1039 
1040 	return bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
1041 					  true);
1042 }
1043 #endif
1044 
1045 #ifdef CONFIG_PM_SLEEP
bmc150_magn_suspend(struct device * dev)1046 static int bmc150_magn_suspend(struct device *dev)
1047 {
1048 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1049 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1050 	int ret;
1051 
1052 	mutex_lock(&data->mutex);
1053 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
1054 					 true);
1055 	mutex_unlock(&data->mutex);
1056 
1057 	return ret;
1058 }
1059 
bmc150_magn_resume(struct device * dev)1060 static int bmc150_magn_resume(struct device *dev)
1061 {
1062 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
1063 	struct bmc150_magn_data *data = iio_priv(indio_dev);
1064 	int ret;
1065 
1066 	mutex_lock(&data->mutex);
1067 	ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
1068 					 true);
1069 	mutex_unlock(&data->mutex);
1070 
1071 	return ret;
1072 }
1073 #endif
1074 
1075 const struct dev_pm_ops bmc150_magn_pm_ops = {
1076 	SET_SYSTEM_SLEEP_PM_OPS(bmc150_magn_suspend, bmc150_magn_resume)
1077 	SET_RUNTIME_PM_OPS(bmc150_magn_runtime_suspend,
1078 			   bmc150_magn_runtime_resume, NULL)
1079 };
1080 EXPORT_SYMBOL(bmc150_magn_pm_ops);
1081 
1082 MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
1083 MODULE_LICENSE("GPL v2");
1084 MODULE_DESCRIPTION("BMC150 magnetometer core driver");
1085