xref: /linux/drivers/iio/imu/bno055/bno055.c (revision ae22a94997b8a03dcb3c922857c203246711f9d4)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * IIO driver for Bosch BNO055 IMU
4  *
5  * Copyright (C) 2021-2022 Istituto Italiano di Tecnologia
6  * Electronic Design Laboratory
7  * Written by Andrea Merello <andrea.merello@iit.it>
8  *
9  * Portions of this driver are taken from the BNO055 driver patch
10  * from Vlad Dogaru which is Copyright (c) 2016, Intel Corporation.
11  *
12  * This driver is also based on BMI160 driver, which is:
13  *	Copyright (c) 2016, Intel Corporation.
14  *	Copyright (c) 2019, Martin Kelly.
15  */
16 
17 #include <linux/bitfield.h>
18 #include <linux/bitmap.h>
19 #include <linux/clk.h>
20 #include <linux/debugfs.h>
21 #include <linux/device.h>
22 #include <linux/firmware.h>
23 #include <linux/gpio/consumer.h>
24 #include <linux/module.h>
25 #include <linux/mutex.h>
26 #include <linux/regmap.h>
27 #include <linux/util_macros.h>
28 
29 #include <linux/iio/buffer.h>
30 #include <linux/iio/iio.h>
31 #include <linux/iio/sysfs.h>
32 #include <linux/iio/trigger_consumer.h>
33 #include <linux/iio/triggered_buffer.h>
34 
35 #include "bno055.h"
36 
37 #define BNO055_FW_UID_FMT "bno055-caldata-%*phN.dat"
38 #define BNO055_FW_GENERIC_NAME "bno055-caldata.dat"
39 
40 /* common registers */
41 #define BNO055_PAGESEL_REG		0x7
42 
43 /* page 0 registers */
44 #define BNO055_CHIP_ID_REG		0x0
45 #define BNO055_CHIP_ID_MAGIC 0xA0
46 #define BNO055_SW_REV_LSB_REG		0x4
47 #define BNO055_SW_REV_MSB_REG		0x5
48 #define BNO055_ACC_DATA_X_LSB_REG	0x8
49 #define BNO055_ACC_DATA_Y_LSB_REG	0xA
50 #define BNO055_ACC_DATA_Z_LSB_REG	0xC
51 #define BNO055_MAG_DATA_X_LSB_REG	0xE
52 #define BNO055_MAG_DATA_Y_LSB_REG	0x10
53 #define BNO055_MAG_DATA_Z_LSB_REG	0x12
54 #define BNO055_GYR_DATA_X_LSB_REG	0x14
55 #define BNO055_GYR_DATA_Y_LSB_REG	0x16
56 #define BNO055_GYR_DATA_Z_LSB_REG	0x18
57 #define BNO055_EUL_DATA_X_LSB_REG	0x1A
58 #define BNO055_EUL_DATA_Y_LSB_REG	0x1C
59 #define BNO055_EUL_DATA_Z_LSB_REG	0x1E
60 #define BNO055_QUAT_DATA_W_LSB_REG	0x20
61 #define BNO055_LIA_DATA_X_LSB_REG	0x28
62 #define BNO055_LIA_DATA_Y_LSB_REG	0x2A
63 #define BNO055_LIA_DATA_Z_LSB_REG	0x2C
64 #define BNO055_GRAVITY_DATA_X_LSB_REG	0x2E
65 #define BNO055_GRAVITY_DATA_Y_LSB_REG	0x30
66 #define BNO055_GRAVITY_DATA_Z_LSB_REG	0x32
67 #define BNO055_SCAN_CH_COUNT ((BNO055_GRAVITY_DATA_Z_LSB_REG - BNO055_ACC_DATA_X_LSB_REG) / 2)
68 #define BNO055_TEMP_REG			0x34
69 #define BNO055_CALIB_STAT_REG		0x35
70 #define BNO055_CALIB_STAT_MAGN_SHIFT 0
71 #define BNO055_CALIB_STAT_ACCEL_SHIFT 2
72 #define BNO055_CALIB_STAT_GYRO_SHIFT 4
73 #define BNO055_CALIB_STAT_SYS_SHIFT 6
74 #define BNO055_SYS_ERR_REG		0x3A
75 #define BNO055_POWER_MODE_REG		0x3E
76 #define BNO055_POWER_MODE_NORMAL 0
77 #define BNO055_SYS_TRIGGER_REG		0x3F
78 #define BNO055_SYS_TRIGGER_RST_SYS BIT(5)
79 #define BNO055_SYS_TRIGGER_CLK_SEL BIT(7)
80 #define BNO055_OPR_MODE_REG		0x3D
81 #define BNO055_OPR_MODE_CONFIG 0x0
82 #define BNO055_OPR_MODE_AMG 0x7
83 #define BNO055_OPR_MODE_FUSION_FMC_OFF 0xB
84 #define BNO055_OPR_MODE_FUSION 0xC
85 #define BNO055_UNIT_SEL_REG		0x3B
86 /* Android orientation mode means: pitch value decreases turning clockwise */
87 #define BNO055_UNIT_SEL_ANDROID BIT(7)
88 #define BNO055_UNIT_SEL_GYR_RPS BIT(1)
89 #define BNO055_CALDATA_START		0x55
90 #define BNO055_CALDATA_END		0x6A
91 #define BNO055_CALDATA_LEN 22
92 
93 /*
94  * The difference in address between the register that contains the
95  * value and the register that contains the offset.  This applies for
96  * accel, gyro and magn channels.
97  */
98 #define BNO055_REG_OFFSET_ADDR		0x4D
99 
100 /* page 1 registers */
101 #define BNO055_PG1(x) ((x) | 0x80)
102 #define BNO055_ACC_CONFIG_REG		BNO055_PG1(0x8)
103 #define BNO055_ACC_CONFIG_LPF_MASK GENMASK(4, 2)
104 #define BNO055_ACC_CONFIG_RANGE_MASK GENMASK(1, 0)
105 #define BNO055_MAG_CONFIG_REG		BNO055_PG1(0x9)
106 #define BNO055_MAG_CONFIG_HIGHACCURACY 0x18
107 #define BNO055_MAG_CONFIG_ODR_MASK GENMASK(2, 0)
108 #define BNO055_GYR_CONFIG_REG		BNO055_PG1(0xA)
109 #define BNO055_GYR_CONFIG_RANGE_MASK GENMASK(2, 0)
110 #define BNO055_GYR_CONFIG_LPF_MASK GENMASK(5, 3)
111 #define BNO055_GYR_AM_SET_REG		BNO055_PG1(0x1F)
112 #define BNO055_UID_LOWER_REG		BNO055_PG1(0x50)
113 #define BNO055_UID_HIGHER_REG		BNO055_PG1(0x5F)
114 #define BNO055_UID_LEN 16
115 
116 struct bno055_sysfs_attr {
117 	int *vals;
118 	int len;
119 	int *fusion_vals;
120 	int *hw_xlate;
121 	int type;
122 };
123 
124 static int bno055_acc_lpf_vals[] = {
125 	7, 810000, 15, 630000, 31, 250000, 62, 500000,
126 	125, 0, 250, 0, 500, 0, 1000, 0,
127 };
128 
129 static struct bno055_sysfs_attr bno055_acc_lpf = {
130 	.vals = bno055_acc_lpf_vals,
131 	.len = ARRAY_SIZE(bno055_acc_lpf_vals),
132 	.fusion_vals = (int[]){62, 500000},
133 	.type = IIO_VAL_INT_PLUS_MICRO,
134 };
135 
136 static int bno055_acc_range_vals[] = {
137   /* G:    2,    4,    8,    16 */
138 	1962, 3924, 7848, 15696
139 };
140 
141 static struct bno055_sysfs_attr bno055_acc_range = {
142 	.vals = bno055_acc_range_vals,
143 	.len = ARRAY_SIZE(bno055_acc_range_vals),
144 	.fusion_vals = (int[]){3924}, /* 4G */
145 	.type = IIO_VAL_INT,
146 };
147 
148 /*
149  * Theoretically the IMU should return data in a given (i.e. fixed) unit
150  * regardless of the range setting. This happens for the accelerometer, but not
151  * for the gyroscope; the gyroscope range setting affects the scale.
152  * This is probably due to this[0] bug.
153  * For this reason we map the internal range setting onto the standard IIO scale
154  * attribute for gyro.
155  * Since the bug[0] may be fixed in future, we check for the IMU FW version and
156  * eventually warn the user.
157  * Currently we just don't care about "range" attributes for gyro.
158  *
159  * [0]  https://community.bosch-sensortec.com/t5/MEMS-sensors-forum/BNO055-Wrong-sensitivity-resolution-in-datasheet/td-p/10266
160  */
161 
162 /*
163  * dps = hwval * (dps_range/2^15)
164  * rps = hwval * (rps_range/2^15)
165  *     = hwval * (dps_range/(2^15 * k))
166  * where k is rad-to-deg factor
167  */
168 static int bno055_gyr_scale_vals[] = {
169 	125, 1877467, 250, 1877467, 500, 1877467,
170 	1000, 1877467, 2000, 1877467,
171 };
172 
173 static struct bno055_sysfs_attr bno055_gyr_scale = {
174 	.vals = bno055_gyr_scale_vals,
175 	.len = ARRAY_SIZE(bno055_gyr_scale_vals),
176 	.fusion_vals = (int[]){1, 900},
177 	.hw_xlate = (int[]){4, 3, 2, 1, 0},
178 	.type = IIO_VAL_FRACTIONAL,
179 };
180 
181 static int bno055_gyr_lpf_vals[] = {12, 23, 32, 47, 64, 116, 230, 523};
182 static struct bno055_sysfs_attr bno055_gyr_lpf = {
183 	.vals = bno055_gyr_lpf_vals,
184 	.len = ARRAY_SIZE(bno055_gyr_lpf_vals),
185 	.fusion_vals = (int[]){32},
186 	.hw_xlate = (int[]){5, 4, 7, 3, 6, 2, 1, 0},
187 	.type = IIO_VAL_INT,
188 };
189 
190 static int bno055_mag_odr_vals[] = {2, 6, 8, 10, 15, 20, 25, 30};
191 static struct bno055_sysfs_attr bno055_mag_odr = {
192 	.vals = bno055_mag_odr_vals,
193 	.len =  ARRAY_SIZE(bno055_mag_odr_vals),
194 	.fusion_vals = (int[]){20},
195 	.type = IIO_VAL_INT,
196 };
197 
198 struct bno055_priv {
199 	struct regmap *regmap;
200 	struct device *dev;
201 	struct clk *clk;
202 	int operation_mode;
203 	int xfer_burst_break_thr;
204 	struct mutex lock;
205 	u8 uid[BNO055_UID_LEN];
206 	struct gpio_desc *reset_gpio;
207 	bool sw_reset;
208 	struct {
209 		__le16 chans[BNO055_SCAN_CH_COUNT];
210 		s64 timestamp __aligned(8);
211 	} buf;
212 	struct dentry *debugfs;
213 };
214 
215 static bool bno055_regmap_volatile(struct device *dev, unsigned int reg)
216 {
217 	/* data and status registers */
218 	if (reg >= BNO055_ACC_DATA_X_LSB_REG && reg <= BNO055_SYS_ERR_REG)
219 		return true;
220 
221 	/* when in fusion mode, config is updated by chip */
222 	if (reg == BNO055_MAG_CONFIG_REG ||
223 	    reg == BNO055_ACC_CONFIG_REG ||
224 	    reg == BNO055_GYR_CONFIG_REG)
225 		return true;
226 
227 	/* calibration data may be updated by the IMU */
228 	if (reg >= BNO055_CALDATA_START && reg <= BNO055_CALDATA_END)
229 		return true;
230 
231 	return false;
232 }
233 
234 static bool bno055_regmap_readable(struct device *dev, unsigned int reg)
235 {
236 	/* unnamed PG0 reserved areas */
237 	if ((reg < BNO055_PG1(0) && reg > BNO055_CALDATA_END) ||
238 	    reg == 0x3C)
239 		return false;
240 
241 	/* unnamed PG1 reserved areas */
242 	if (reg > BNO055_PG1(BNO055_UID_HIGHER_REG) ||
243 	    (reg < BNO055_PG1(BNO055_UID_LOWER_REG) && reg > BNO055_PG1(BNO055_GYR_AM_SET_REG)) ||
244 	    reg == BNO055_PG1(0xE) ||
245 	    (reg < BNO055_PG1(BNO055_PAGESEL_REG) && reg >= BNO055_PG1(0x0)))
246 		return false;
247 	return true;
248 }
249 
250 static bool bno055_regmap_writeable(struct device *dev, unsigned int reg)
251 {
252 	/*
253 	 * Unreadable registers are indeed reserved; there are no WO regs
254 	 * (except for a single bit in SYS_TRIGGER register)
255 	 */
256 	if (!bno055_regmap_readable(dev, reg))
257 		return false;
258 
259 	/* data and status registers */
260 	if (reg >= BNO055_ACC_DATA_X_LSB_REG && reg <= BNO055_SYS_ERR_REG)
261 		return false;
262 
263 	/* ID areas */
264 	if (reg < BNO055_PAGESEL_REG ||
265 	    (reg <= BNO055_UID_HIGHER_REG && reg >= BNO055_UID_LOWER_REG))
266 		return false;
267 
268 	return true;
269 }
270 
271 static const struct regmap_range_cfg bno055_regmap_ranges[] = {
272 	{
273 		.range_min = 0,
274 		.range_max = 0x7f * 2,
275 		.selector_reg = BNO055_PAGESEL_REG,
276 		.selector_mask = GENMASK(7, 0),
277 		.selector_shift = 0,
278 		.window_start = 0,
279 		.window_len = 0x80,
280 	},
281 };
282 
283 const struct regmap_config bno055_regmap_config = {
284 	.name = "bno055",
285 	.reg_bits = 8,
286 	.val_bits = 8,
287 	.ranges = bno055_regmap_ranges,
288 	.num_ranges = 1,
289 	.volatile_reg = bno055_regmap_volatile,
290 	.max_register = 0x80 * 2,
291 	.writeable_reg = bno055_regmap_writeable,
292 	.readable_reg = bno055_regmap_readable,
293 	.cache_type = REGCACHE_RBTREE,
294 };
295 EXPORT_SYMBOL_NS_GPL(bno055_regmap_config, IIO_BNO055);
296 
297 /* must be called in configuration mode */
298 static int bno055_calibration_load(struct bno055_priv *priv, const u8 *data, int len)
299 {
300 	if (len != BNO055_CALDATA_LEN) {
301 		dev_dbg(priv->dev, "Invalid calibration file size %d (expected %d)",
302 			len, BNO055_CALDATA_LEN);
303 		return -EINVAL;
304 	}
305 
306 	dev_dbg(priv->dev, "loading cal data: %*ph", BNO055_CALDATA_LEN, data);
307 	return regmap_bulk_write(priv->regmap, BNO055_CALDATA_START,
308 				 data, BNO055_CALDATA_LEN);
309 }
310 
311 static int bno055_operation_mode_do_set(struct bno055_priv *priv,
312 					int operation_mode)
313 {
314 	int ret;
315 
316 	ret = regmap_write(priv->regmap, BNO055_OPR_MODE_REG,
317 			   operation_mode);
318 	if (ret)
319 		return ret;
320 
321 	/* Following datasheet specifications: sensor takes 7mS up to 19 mS to switch mode */
322 	msleep(20);
323 
324 	return 0;
325 }
326 
327 static int bno055_system_reset(struct bno055_priv *priv)
328 {
329 	int ret;
330 
331 	if (priv->reset_gpio) {
332 		gpiod_set_value_cansleep(priv->reset_gpio, 0);
333 		usleep_range(5000, 10000);
334 		gpiod_set_value_cansleep(priv->reset_gpio, 1);
335 	} else if (priv->sw_reset) {
336 		ret = regmap_write(priv->regmap, BNO055_SYS_TRIGGER_REG,
337 				   BNO055_SYS_TRIGGER_RST_SYS);
338 		if (ret)
339 			return ret;
340 	} else {
341 		return 0;
342 	}
343 
344 	regcache_drop_region(priv->regmap, 0x0, 0xff);
345 	usleep_range(650000, 700000);
346 
347 	return 0;
348 }
349 
350 static int bno055_init(struct bno055_priv *priv, const u8 *caldata, int len)
351 {
352 	int ret;
353 
354 	ret = bno055_operation_mode_do_set(priv, BNO055_OPR_MODE_CONFIG);
355 	if (ret)
356 		return ret;
357 
358 	ret = regmap_write(priv->regmap, BNO055_POWER_MODE_REG,
359 			   BNO055_POWER_MODE_NORMAL);
360 	if (ret)
361 		return ret;
362 
363 	ret = regmap_write(priv->regmap, BNO055_SYS_TRIGGER_REG,
364 			   priv->clk ? BNO055_SYS_TRIGGER_CLK_SEL : 0);
365 	if (ret)
366 		return ret;
367 
368 	/* use standard SI units */
369 	ret = regmap_write(priv->regmap, BNO055_UNIT_SEL_REG,
370 			   BNO055_UNIT_SEL_ANDROID | BNO055_UNIT_SEL_GYR_RPS);
371 	if (ret)
372 		return ret;
373 
374 	if (caldata) {
375 		ret = bno055_calibration_load(priv, caldata, len);
376 		if (ret)
377 			dev_warn(priv->dev, "failed to load calibration data with error %d\n",
378 				 ret);
379 	}
380 
381 	return 0;
382 }
383 
384 static ssize_t bno055_operation_mode_set(struct bno055_priv *priv,
385 					 int operation_mode)
386 {
387 	u8 caldata[BNO055_CALDATA_LEN];
388 	int ret;
389 
390 	mutex_lock(&priv->lock);
391 
392 	ret = bno055_operation_mode_do_set(priv, BNO055_OPR_MODE_CONFIG);
393 	if (ret)
394 		goto exit_unlock;
395 
396 	if (operation_mode == BNO055_OPR_MODE_FUSION ||
397 	    operation_mode == BNO055_OPR_MODE_FUSION_FMC_OFF) {
398 		/* for entering fusion mode, reset the chip to clear the algo state */
399 		ret = regmap_bulk_read(priv->regmap, BNO055_CALDATA_START, caldata,
400 				       BNO055_CALDATA_LEN);
401 		if (ret)
402 			goto exit_unlock;
403 
404 		ret = bno055_system_reset(priv);
405 		if (ret)
406 			goto exit_unlock;
407 
408 		ret = bno055_init(priv, caldata, BNO055_CALDATA_LEN);
409 		if (ret)
410 			goto exit_unlock;
411 	}
412 
413 	ret = bno055_operation_mode_do_set(priv, operation_mode);
414 	if (ret)
415 		goto exit_unlock;
416 
417 	priv->operation_mode = operation_mode;
418 
419 exit_unlock:
420 	mutex_unlock(&priv->lock);
421 	return ret;
422 }
423 
424 static void bno055_uninit(void *arg)
425 {
426 	struct bno055_priv *priv = arg;
427 
428 	/* stop the IMU */
429 	bno055_operation_mode_do_set(priv, BNO055_OPR_MODE_CONFIG);
430 }
431 
432 #define BNO055_CHANNEL(_type, _axis, _index, _address, _sep, _sh, _avail) {	\
433 	.address = _address,							\
434 	.type = _type,								\
435 	.modified = 1,								\
436 	.channel2 = IIO_MOD_##_axis,						\
437 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | (_sep),			\
438 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | (_sh),		\
439 	.info_mask_shared_by_type_available = _avail,				\
440 	.scan_index = _index,							\
441 	.scan_type = {								\
442 		.sign = 's',							\
443 		.realbits = 16,							\
444 		.storagebits = 16,						\
445 		.endianness = IIO_LE,						\
446 		.repeat = IIO_MOD_##_axis == IIO_MOD_QUATERNION ? 4 : 0,        \
447 	},									\
448 }
449 
450 /* scan indexes follow DATA register order */
451 enum bno055_scan_axis {
452 	BNO055_SCAN_ACCEL_X,
453 	BNO055_SCAN_ACCEL_Y,
454 	BNO055_SCAN_ACCEL_Z,
455 	BNO055_SCAN_MAGN_X,
456 	BNO055_SCAN_MAGN_Y,
457 	BNO055_SCAN_MAGN_Z,
458 	BNO055_SCAN_GYRO_X,
459 	BNO055_SCAN_GYRO_Y,
460 	BNO055_SCAN_GYRO_Z,
461 	BNO055_SCAN_YAW,
462 	BNO055_SCAN_ROLL,
463 	BNO055_SCAN_PITCH,
464 	BNO055_SCAN_QUATERNION,
465 	BNO055_SCAN_LIA_X,
466 	BNO055_SCAN_LIA_Y,
467 	BNO055_SCAN_LIA_Z,
468 	BNO055_SCAN_GRAVITY_X,
469 	BNO055_SCAN_GRAVITY_Y,
470 	BNO055_SCAN_GRAVITY_Z,
471 	BNO055_SCAN_TIMESTAMP,
472 	_BNO055_SCAN_MAX
473 };
474 
475 static const struct iio_chan_spec bno055_channels[] = {
476 	/* accelerometer */
477 	BNO055_CHANNEL(IIO_ACCEL, X, BNO055_SCAN_ACCEL_X,
478 		       BNO055_ACC_DATA_X_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
479 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
480 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)),
481 	BNO055_CHANNEL(IIO_ACCEL, Y, BNO055_SCAN_ACCEL_Y,
482 		       BNO055_ACC_DATA_Y_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
483 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
484 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)),
485 	BNO055_CHANNEL(IIO_ACCEL, Z, BNO055_SCAN_ACCEL_Z,
486 		       BNO055_ACC_DATA_Z_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
487 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
488 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)),
489 	/* gyroscope */
490 	BNO055_CHANNEL(IIO_ANGL_VEL, X, BNO055_SCAN_GYRO_X,
491 		       BNO055_GYR_DATA_X_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
492 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
493 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |
494 		       BIT(IIO_CHAN_INFO_SCALE)),
495 	BNO055_CHANNEL(IIO_ANGL_VEL, Y, BNO055_SCAN_GYRO_Y,
496 		       BNO055_GYR_DATA_Y_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
497 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
498 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |
499 		       BIT(IIO_CHAN_INFO_SCALE)),
500 	BNO055_CHANNEL(IIO_ANGL_VEL, Z, BNO055_SCAN_GYRO_Z,
501 		       BNO055_GYR_DATA_Z_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
502 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
503 		       BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY) |
504 		       BIT(IIO_CHAN_INFO_SCALE)),
505 	/* magnetometer */
506 	BNO055_CHANNEL(IIO_MAGN, X, BNO055_SCAN_MAGN_X,
507 		       BNO055_MAG_DATA_X_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
508 		       BIT(IIO_CHAN_INFO_SAMP_FREQ), BIT(IIO_CHAN_INFO_SAMP_FREQ)),
509 	BNO055_CHANNEL(IIO_MAGN, Y, BNO055_SCAN_MAGN_Y,
510 		       BNO055_MAG_DATA_Y_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
511 		       BIT(IIO_CHAN_INFO_SAMP_FREQ), BIT(IIO_CHAN_INFO_SAMP_FREQ)),
512 	BNO055_CHANNEL(IIO_MAGN, Z, BNO055_SCAN_MAGN_Z,
513 		       BNO055_MAG_DATA_Z_LSB_REG, BIT(IIO_CHAN_INFO_OFFSET),
514 		       BIT(IIO_CHAN_INFO_SAMP_FREQ), BIT(IIO_CHAN_INFO_SAMP_FREQ)),
515 	/* euler angle */
516 	BNO055_CHANNEL(IIO_ROT, YAW, BNO055_SCAN_YAW,
517 		       BNO055_EUL_DATA_X_LSB_REG, 0, 0, 0),
518 	BNO055_CHANNEL(IIO_ROT, ROLL, BNO055_SCAN_ROLL,
519 		       BNO055_EUL_DATA_Y_LSB_REG, 0, 0, 0),
520 	BNO055_CHANNEL(IIO_ROT, PITCH, BNO055_SCAN_PITCH,
521 		       BNO055_EUL_DATA_Z_LSB_REG, 0, 0, 0),
522 	/* quaternion */
523 	BNO055_CHANNEL(IIO_ROT, QUATERNION, BNO055_SCAN_QUATERNION,
524 		       BNO055_QUAT_DATA_W_LSB_REG, 0, 0, 0),
525 
526 	/* linear acceleration */
527 	BNO055_CHANNEL(IIO_ACCEL, LINEAR_X, BNO055_SCAN_LIA_X,
528 		       BNO055_LIA_DATA_X_LSB_REG, 0, 0, 0),
529 	BNO055_CHANNEL(IIO_ACCEL, LINEAR_Y, BNO055_SCAN_LIA_Y,
530 		       BNO055_LIA_DATA_Y_LSB_REG, 0, 0, 0),
531 	BNO055_CHANNEL(IIO_ACCEL, LINEAR_Z, BNO055_SCAN_LIA_Z,
532 		       BNO055_LIA_DATA_Z_LSB_REG, 0, 0, 0),
533 
534 	/* gravity vector */
535 	BNO055_CHANNEL(IIO_GRAVITY, X, BNO055_SCAN_GRAVITY_X,
536 		       BNO055_GRAVITY_DATA_X_LSB_REG, 0, 0, 0),
537 	BNO055_CHANNEL(IIO_GRAVITY, Y, BNO055_SCAN_GRAVITY_Y,
538 		       BNO055_GRAVITY_DATA_Y_LSB_REG, 0, 0, 0),
539 	BNO055_CHANNEL(IIO_GRAVITY, Z, BNO055_SCAN_GRAVITY_Z,
540 		       BNO055_GRAVITY_DATA_Z_LSB_REG, 0, 0, 0),
541 
542 	{
543 		.type = IIO_TEMP,
544 		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
545 		.scan_index = -1,
546 	},
547 	IIO_CHAN_SOFT_TIMESTAMP(BNO055_SCAN_TIMESTAMP),
548 };
549 
550 static int bno055_get_regmask(struct bno055_priv *priv, int *val, int *val2,
551 			      int reg, int mask, struct bno055_sysfs_attr *attr)
552 {
553 	const int shift = __ffs(mask);
554 	int hwval, idx;
555 	int ret;
556 	int i;
557 
558 	ret = regmap_read(priv->regmap, reg, &hwval);
559 	if (ret)
560 		return ret;
561 
562 	idx = (hwval & mask) >> shift;
563 	if (attr->hw_xlate)
564 		for (i = 0; i < attr->len; i++)
565 			if (attr->hw_xlate[i] == idx) {
566 				idx = i;
567 				break;
568 			}
569 	if (attr->type == IIO_VAL_INT) {
570 		*val = attr->vals[idx];
571 	} else { /* IIO_VAL_INT_PLUS_MICRO or IIO_VAL_FRACTIONAL */
572 		*val = attr->vals[idx * 2];
573 		*val2 = attr->vals[idx * 2 + 1];
574 	}
575 
576 	return attr->type;
577 }
578 
579 static int bno055_set_regmask(struct bno055_priv *priv, int val, int val2,
580 			      int reg, int mask, struct bno055_sysfs_attr *attr)
581 {
582 	const int shift = __ffs(mask);
583 	int best_delta;
584 	int req_val;
585 	int tbl_val;
586 	bool first;
587 	int delta;
588 	int hwval;
589 	int ret;
590 	int len;
591 	int i;
592 
593 	/*
594 	 * The closest value the HW supports is only one in fusion mode,
595 	 * and it is autoselected, so don't do anything, just return OK,
596 	 * as the closest possible value has been (virtually) selected
597 	 */
598 	if (priv->operation_mode != BNO055_OPR_MODE_AMG)
599 		return 0;
600 
601 	len = attr->len;
602 
603 	/*
604 	 * We always get a request in INT_PLUS_MICRO, but we
605 	 * take care of the micro part only when we really have
606 	 * non-integer tables. This prevents 32-bit overflow with
607 	 * larger integers contained in integer tables.
608 	 */
609 	req_val = val;
610 	if (attr->type != IIO_VAL_INT) {
611 		len /= 2;
612 		req_val = min(val, 2147) * 1000000 + val2;
613 	}
614 
615 	first = true;
616 	for (i = 0; i < len; i++) {
617 		switch (attr->type) {
618 		case IIO_VAL_INT:
619 			tbl_val = attr->vals[i];
620 			break;
621 		case IIO_VAL_INT_PLUS_MICRO:
622 			WARN_ON(attr->vals[i * 2] > 2147);
623 			tbl_val = attr->vals[i * 2] * 1000000 +
624 				attr->vals[i * 2 + 1];
625 			break;
626 		case IIO_VAL_FRACTIONAL:
627 			WARN_ON(attr->vals[i * 2] > 4294);
628 			tbl_val = attr->vals[i * 2] * 1000000 /
629 				attr->vals[i * 2 + 1];
630 			break;
631 		default:
632 			return -EINVAL;
633 		}
634 		delta = abs(tbl_val - req_val);
635 		if (first || delta < best_delta) {
636 			best_delta = delta;
637 			hwval = i;
638 			first = false;
639 		}
640 	}
641 
642 	if (attr->hw_xlate)
643 		hwval = attr->hw_xlate[hwval];
644 
645 	ret = bno055_operation_mode_do_set(priv, BNO055_OPR_MODE_CONFIG);
646 	if (ret)
647 		return ret;
648 
649 	ret = regmap_update_bits(priv->regmap, reg, mask, hwval << shift);
650 	if (ret)
651 		return ret;
652 
653 	return bno055_operation_mode_do_set(priv, BNO055_OPR_MODE_AMG);
654 }
655 
656 static int bno055_read_simple_chan(struct iio_dev *indio_dev,
657 				   struct iio_chan_spec const *chan,
658 				   int *val, int *val2, long mask)
659 {
660 	struct bno055_priv *priv = iio_priv(indio_dev);
661 	__le16 raw_val;
662 	int ret;
663 
664 	switch (mask) {
665 	case IIO_CHAN_INFO_RAW:
666 		ret = regmap_bulk_read(priv->regmap, chan->address,
667 				       &raw_val, sizeof(raw_val));
668 		if (ret < 0)
669 			return ret;
670 		*val = sign_extend32(le16_to_cpu(raw_val), 15);
671 		return IIO_VAL_INT;
672 	case IIO_CHAN_INFO_OFFSET:
673 		if (priv->operation_mode != BNO055_OPR_MODE_AMG) {
674 			*val = 0;
675 		} else {
676 			ret = regmap_bulk_read(priv->regmap,
677 					       chan->address +
678 					       BNO055_REG_OFFSET_ADDR,
679 					       &raw_val, sizeof(raw_val));
680 			if (ret < 0)
681 				return ret;
682 			/*
683 			 * IMU reports sensor offsets; IIO wants correction
684 			 * offsets, thus we need the 'minus' here.
685 			 */
686 			*val = -sign_extend32(le16_to_cpu(raw_val), 15);
687 		}
688 		return IIO_VAL_INT;
689 	case IIO_CHAN_INFO_SCALE:
690 		*val = 1;
691 		switch (chan->type) {
692 		case IIO_GRAVITY:
693 			/* Table 3-35: 1 m/s^2 = 100 LSB */
694 		case IIO_ACCEL:
695 			/* Table 3-17: 1 m/s^2 = 100 LSB */
696 			*val2 = 100;
697 			break;
698 		case IIO_MAGN:
699 			/*
700 			 * Table 3-19: 1 uT = 16 LSB.  But we need
701 			 * Gauss: 1G = 0.1 uT.
702 			 */
703 			*val2 = 160;
704 			break;
705 		case IIO_ANGL_VEL:
706 			/*
707 			 * Table 3-22: 1 Rps = 900 LSB
708 			 * .. but this is not exactly true. See comment at the
709 			 * beginning of this file.
710 			 */
711 			if (priv->operation_mode != BNO055_OPR_MODE_AMG) {
712 				*val = bno055_gyr_scale.fusion_vals[0];
713 				*val2 = bno055_gyr_scale.fusion_vals[1];
714 				return IIO_VAL_FRACTIONAL;
715 			}
716 
717 			return bno055_get_regmask(priv, val, val2,
718 						  BNO055_GYR_CONFIG_REG,
719 						  BNO055_GYR_CONFIG_RANGE_MASK,
720 						  &bno055_gyr_scale);
721 			break;
722 		case IIO_ROT:
723 			/* Table 3-28: 1 degree = 16 LSB */
724 			*val2 = 16;
725 			break;
726 		default:
727 			return -EINVAL;
728 		}
729 		return IIO_VAL_FRACTIONAL;
730 
731 	case IIO_CHAN_INFO_SAMP_FREQ:
732 		if (chan->type != IIO_MAGN)
733 			return -EINVAL;
734 
735 		return bno055_get_regmask(priv, val, val2,
736 					  BNO055_MAG_CONFIG_REG,
737 					  BNO055_MAG_CONFIG_ODR_MASK,
738 					  &bno055_mag_odr);
739 
740 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
741 		switch (chan->type) {
742 		case IIO_ANGL_VEL:
743 			return bno055_get_regmask(priv, val, val2,
744 						  BNO055_GYR_CONFIG_REG,
745 						  BNO055_GYR_CONFIG_LPF_MASK,
746 						  &bno055_gyr_lpf);
747 		case IIO_ACCEL:
748 			return bno055_get_regmask(priv, val, val2,
749 						  BNO055_ACC_CONFIG_REG,
750 						  BNO055_ACC_CONFIG_LPF_MASK,
751 						  &bno055_acc_lpf);
752 		default:
753 			return -EINVAL;
754 		}
755 
756 	default:
757 		return -EINVAL;
758 	}
759 }
760 
761 static int bno055_sysfs_attr_avail(struct bno055_priv *priv, struct bno055_sysfs_attr *attr,
762 				   const int **vals, int *length)
763 {
764 	if (priv->operation_mode != BNO055_OPR_MODE_AMG) {
765 		/* locked when fusion enabled */
766 		*vals = attr->fusion_vals;
767 		if (attr->type == IIO_VAL_INT)
768 			*length = 1;
769 		else
770 			*length = 2; /* IIO_VAL_INT_PLUS_MICRO or IIO_VAL_FRACTIONAL*/
771 	} else {
772 		*vals = attr->vals;
773 		*length = attr->len;
774 	}
775 
776 	return attr->type;
777 }
778 
779 static int bno055_read_avail(struct iio_dev *indio_dev,
780 			     struct iio_chan_spec const *chan,
781 			     const int **vals, int *type, int *length,
782 			     long mask)
783 {
784 	struct bno055_priv *priv = iio_priv(indio_dev);
785 
786 	switch (mask) {
787 	case IIO_CHAN_INFO_SCALE:
788 		switch (chan->type) {
789 		case IIO_ANGL_VEL:
790 			*type = bno055_sysfs_attr_avail(priv, &bno055_gyr_scale,
791 							vals, length);
792 			return IIO_AVAIL_LIST;
793 		default:
794 			return -EINVAL;
795 		}
796 	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
797 		switch (chan->type) {
798 		case IIO_ANGL_VEL:
799 			*type = bno055_sysfs_attr_avail(priv, &bno055_gyr_lpf,
800 							vals, length);
801 			return IIO_AVAIL_LIST;
802 		case IIO_ACCEL:
803 			*type = bno055_sysfs_attr_avail(priv, &bno055_acc_lpf,
804 							vals, length);
805 			return IIO_AVAIL_LIST;
806 		default:
807 			return -EINVAL;
808 		}
809 
810 		break;
811 	case IIO_CHAN_INFO_SAMP_FREQ:
812 		switch (chan->type) {
813 		case IIO_MAGN:
814 			*type = bno055_sysfs_attr_avail(priv, &bno055_mag_odr,
815 							vals, length);
816 			return IIO_AVAIL_LIST;
817 		default:
818 			return -EINVAL;
819 		}
820 	default:
821 		return -EINVAL;
822 	}
823 }
824 
825 static int bno055_read_temp_chan(struct iio_dev *indio_dev, int *val)
826 {
827 	struct bno055_priv *priv = iio_priv(indio_dev);
828 	unsigned int raw_val;
829 	int ret;
830 
831 	ret = regmap_read(priv->regmap, BNO055_TEMP_REG, &raw_val);
832 	if (ret < 0)
833 		return ret;
834 
835 	/*
836 	 * Tables 3-36 and 3-37: one byte of priv, signed, 1 LSB = 1C.
837 	 * ABI wants milliC.
838 	 */
839 	*val = raw_val * 1000;
840 
841 	return IIO_VAL_INT;
842 }
843 
844 static int bno055_read_quaternion(struct iio_dev *indio_dev,
845 				  struct iio_chan_spec const *chan,
846 				  int size, int *vals, int *val_len,
847 				  long mask)
848 {
849 	struct bno055_priv *priv = iio_priv(indio_dev);
850 	__le16 raw_vals[4];
851 	int i, ret;
852 
853 	switch (mask) {
854 	case IIO_CHAN_INFO_RAW:
855 		if (size < 4)
856 			return -EINVAL;
857 		ret = regmap_bulk_read(priv->regmap,
858 				       BNO055_QUAT_DATA_W_LSB_REG,
859 				       raw_vals, sizeof(raw_vals));
860 		if (ret < 0)
861 			return ret;
862 		for (i = 0; i < 4; i++)
863 			vals[i] = sign_extend32(le16_to_cpu(raw_vals[i]), 15);
864 		*val_len = 4;
865 		return IIO_VAL_INT_MULTIPLE;
866 	case IIO_CHAN_INFO_SCALE:
867 		/* Table 3-31: 1 quaternion = 2^14 LSB */
868 		if (size < 2)
869 			return -EINVAL;
870 		vals[0] = 1;
871 		vals[1] = 14;
872 		return IIO_VAL_FRACTIONAL_LOG2;
873 	default:
874 		return -EINVAL;
875 	}
876 }
877 
878 static bool bno055_is_chan_readable(struct iio_dev *indio_dev,
879 				    struct iio_chan_spec const *chan)
880 {
881 	struct bno055_priv *priv = iio_priv(indio_dev);
882 
883 	if (priv->operation_mode != BNO055_OPR_MODE_AMG)
884 		return true;
885 
886 	switch (chan->type) {
887 	case IIO_GRAVITY:
888 	case IIO_ROT:
889 		return false;
890 	case IIO_ACCEL:
891 		if (chan->channel2 == IIO_MOD_LINEAR_X ||
892 		    chan->channel2 == IIO_MOD_LINEAR_Y ||
893 		    chan->channel2 == IIO_MOD_LINEAR_Z)
894 			return false;
895 		return true;
896 	default:
897 		return true;
898 	}
899 }
900 
901 static int _bno055_read_raw_multi(struct iio_dev *indio_dev,
902 				  struct iio_chan_spec const *chan,
903 				  int size, int *vals, int *val_len,
904 				  long mask)
905 {
906 	if (!bno055_is_chan_readable(indio_dev, chan))
907 		return -EBUSY;
908 
909 	switch (chan->type) {
910 	case IIO_MAGN:
911 	case IIO_ACCEL:
912 	case IIO_ANGL_VEL:
913 	case IIO_GRAVITY:
914 		if (size < 2)
915 			return -EINVAL;
916 		*val_len = 2;
917 		return bno055_read_simple_chan(indio_dev, chan,
918 					       &vals[0], &vals[1],
919 					       mask);
920 	case IIO_TEMP:
921 		*val_len = 1;
922 		return bno055_read_temp_chan(indio_dev, &vals[0]);
923 	case IIO_ROT:
924 		/*
925 		 * Rotation is exposed as either a quaternion or three
926 		 * Euler angles.
927 		 */
928 		if (chan->channel2 == IIO_MOD_QUATERNION)
929 			return bno055_read_quaternion(indio_dev, chan,
930 						      size, vals,
931 						      val_len, mask);
932 		if (size < 2)
933 			return -EINVAL;
934 		*val_len = 2;
935 		return bno055_read_simple_chan(indio_dev, chan,
936 					       &vals[0], &vals[1],
937 					       mask);
938 	default:
939 		return -EINVAL;
940 	}
941 }
942 
943 static int bno055_read_raw_multi(struct iio_dev *indio_dev,
944 				 struct iio_chan_spec const *chan,
945 				 int size, int *vals, int *val_len,
946 				 long mask)
947 {
948 	struct bno055_priv *priv = iio_priv(indio_dev);
949 	int ret;
950 
951 	mutex_lock(&priv->lock);
952 	ret = _bno055_read_raw_multi(indio_dev, chan, size,
953 				     vals, val_len, mask);
954 	mutex_unlock(&priv->lock);
955 	return ret;
956 }
957 
958 static int _bno055_write_raw(struct iio_dev *iio_dev,
959 			     struct iio_chan_spec const *chan,
960 			     int val, int val2, long mask)
961 {
962 	struct bno055_priv *priv = iio_priv(iio_dev);
963 
964 	switch (chan->type) {
965 	case IIO_MAGN:
966 		switch (mask) {
967 		case IIO_CHAN_INFO_SAMP_FREQ:
968 			return bno055_set_regmask(priv, val, val2,
969 						  BNO055_MAG_CONFIG_REG,
970 						  BNO055_MAG_CONFIG_ODR_MASK,
971 						  &bno055_mag_odr);
972 		default:
973 			return -EINVAL;
974 		}
975 	case IIO_ACCEL:
976 		switch (mask) {
977 		case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
978 			return bno055_set_regmask(priv, val, val2,
979 						  BNO055_ACC_CONFIG_REG,
980 						  BNO055_ACC_CONFIG_LPF_MASK,
981 						  &bno055_acc_lpf);
982 
983 		default:
984 			return -EINVAL;
985 		}
986 	case IIO_ANGL_VEL:
987 		switch (mask) {
988 		case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
989 			return bno055_set_regmask(priv, val, val2,
990 						  BNO055_GYR_CONFIG_REG,
991 						  BNO055_GYR_CONFIG_LPF_MASK,
992 						  &bno055_gyr_lpf);
993 		case IIO_CHAN_INFO_SCALE:
994 			return bno055_set_regmask(priv, val, val2,
995 						  BNO055_GYR_CONFIG_REG,
996 						  BNO055_GYR_CONFIG_RANGE_MASK,
997 						  &bno055_gyr_scale);
998 		default:
999 			return -EINVAL;
1000 		}
1001 	default:
1002 		return -EINVAL;
1003 	}
1004 }
1005 
1006 static int bno055_write_raw(struct iio_dev *iio_dev,
1007 			    struct iio_chan_spec const *chan,
1008 			    int val, int val2, long mask)
1009 {
1010 	struct bno055_priv *priv = iio_priv(iio_dev);
1011 	int ret;
1012 
1013 	mutex_lock(&priv->lock);
1014 	ret = _bno055_write_raw(iio_dev, chan, val, val2, mask);
1015 	mutex_unlock(&priv->lock);
1016 
1017 	return ret;
1018 }
1019 
1020 static ssize_t in_accel_range_raw_available_show(struct device *dev,
1021 						 struct device_attribute *attr,
1022 						 char *buf)
1023 {
1024 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(dev));
1025 	int len = 0;
1026 	int i;
1027 
1028 	if (priv->operation_mode != BNO055_OPR_MODE_AMG)
1029 		return sysfs_emit(buf, "%d\n", bno055_acc_range.fusion_vals[0]);
1030 
1031 	for (i = 0; i < bno055_acc_range.len; i++)
1032 		len += sysfs_emit_at(buf, len, "%d ", bno055_acc_range.vals[i]);
1033 	buf[len - 1] = '\n';
1034 
1035 	return len;
1036 }
1037 
1038 static ssize_t fusion_enable_show(struct device *dev,
1039 				  struct device_attribute *attr,
1040 				  char *buf)
1041 {
1042 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(dev));
1043 
1044 	return sysfs_emit(buf, "%d\n",
1045 			  priv->operation_mode != BNO055_OPR_MODE_AMG);
1046 }
1047 
1048 static ssize_t fusion_enable_store(struct device *dev,
1049 				   struct device_attribute *attr,
1050 				   const char *buf, size_t len)
1051 {
1052 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1053 	struct bno055_priv *priv = iio_priv(indio_dev);
1054 	bool en;
1055 	int ret;
1056 
1057 	if (indio_dev->active_scan_mask &&
1058 	    !bitmap_empty(indio_dev->active_scan_mask, _BNO055_SCAN_MAX))
1059 		return -EBUSY;
1060 
1061 	ret = kstrtobool(buf, &en);
1062 	if (ret)
1063 		return -EINVAL;
1064 
1065 	if (!en)
1066 		return bno055_operation_mode_set(priv, BNO055_OPR_MODE_AMG) ?: len;
1067 
1068 	/*
1069 	 * Coming from AMG means the FMC was off, just switch to fusion but
1070 	 * don't change anything that doesn't belong to us (i.e let FMC stay off).
1071 	 * Coming from any other fusion mode means we don't need to do anything.
1072 	 */
1073 	if (priv->operation_mode == BNO055_OPR_MODE_AMG)
1074 		return  bno055_operation_mode_set(priv, BNO055_OPR_MODE_FUSION_FMC_OFF) ?: len;
1075 
1076 	return len;
1077 }
1078 
1079 static ssize_t in_magn_calibration_fast_enable_show(struct device *dev,
1080 						    struct device_attribute *attr,
1081 						    char *buf)
1082 {
1083 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(dev));
1084 
1085 	return sysfs_emit(buf, "%d\n",
1086 			  priv->operation_mode == BNO055_OPR_MODE_FUSION);
1087 }
1088 
1089 static ssize_t in_magn_calibration_fast_enable_store(struct device *dev,
1090 						     struct device_attribute *attr,
1091 						     const char *buf, size_t len)
1092 {
1093 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
1094 	struct bno055_priv *priv = iio_priv(indio_dev);
1095 	int ret;
1096 
1097 	if (indio_dev->active_scan_mask &&
1098 	    !bitmap_empty(indio_dev->active_scan_mask, _BNO055_SCAN_MAX))
1099 		return -EBUSY;
1100 
1101 	if (sysfs_streq(buf, "0")) {
1102 		if (priv->operation_mode == BNO055_OPR_MODE_FUSION) {
1103 			ret = bno055_operation_mode_set(priv, BNO055_OPR_MODE_FUSION_FMC_OFF);
1104 			if (ret)
1105 				return ret;
1106 		}
1107 	} else {
1108 		if (priv->operation_mode == BNO055_OPR_MODE_AMG)
1109 			return -EINVAL;
1110 
1111 		if (priv->operation_mode != BNO055_OPR_MODE_FUSION) {
1112 			ret = bno055_operation_mode_set(priv, BNO055_OPR_MODE_FUSION);
1113 			if (ret)
1114 				return ret;
1115 		}
1116 	}
1117 
1118 	return len;
1119 }
1120 
1121 static ssize_t in_accel_range_raw_show(struct device *dev,
1122 				       struct device_attribute *attr,
1123 				       char *buf)
1124 {
1125 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(dev));
1126 	int val;
1127 	int ret;
1128 
1129 	ret = bno055_get_regmask(priv, &val, NULL,
1130 				 BNO055_ACC_CONFIG_REG,
1131 				 BNO055_ACC_CONFIG_RANGE_MASK,
1132 				 &bno055_acc_range);
1133 	if (ret < 0)
1134 		return ret;
1135 
1136 	return sysfs_emit(buf, "%d\n", val);
1137 }
1138 
1139 static ssize_t in_accel_range_raw_store(struct device *dev,
1140 					struct device_attribute *attr,
1141 					const char *buf, size_t len)
1142 {
1143 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(dev));
1144 	unsigned long val;
1145 	int ret;
1146 
1147 	ret = kstrtoul(buf, 10, &val);
1148 	if (ret)
1149 		return ret;
1150 
1151 	mutex_lock(&priv->lock);
1152 	ret = bno055_set_regmask(priv, val, 0,
1153 				 BNO055_ACC_CONFIG_REG,
1154 				 BNO055_ACC_CONFIG_RANGE_MASK,
1155 				 &bno055_acc_range);
1156 	mutex_unlock(&priv->lock);
1157 
1158 	return ret ?: len;
1159 }
1160 
1161 static ssize_t bno055_get_calib_status(struct device *dev, char *buf, int which)
1162 {
1163 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(dev));
1164 	int calib;
1165 	int ret;
1166 	int val;
1167 
1168 	if (priv->operation_mode == BNO055_OPR_MODE_AMG ||
1169 	    (priv->operation_mode == BNO055_OPR_MODE_FUSION_FMC_OFF &&
1170 	     which == BNO055_CALIB_STAT_MAGN_SHIFT)) {
1171 		calib = 0;
1172 	} else {
1173 		mutex_lock(&priv->lock);
1174 		ret = regmap_read(priv->regmap, BNO055_CALIB_STAT_REG, &val);
1175 		mutex_unlock(&priv->lock);
1176 
1177 		if (ret)
1178 			return -EIO;
1179 
1180 		calib = ((val >> which) & GENMASK(1, 0)) + 1;
1181 	}
1182 
1183 	return sysfs_emit(buf, "%d\n", calib);
1184 }
1185 
1186 static ssize_t serialnumber_show(struct device *dev,
1187 				 struct device_attribute *attr,
1188 				 char *buf)
1189 {
1190 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(dev));
1191 
1192 	return sysfs_emit(buf, "%*ph\n", BNO055_UID_LEN, priv->uid);
1193 }
1194 
1195 static ssize_t calibration_data_read(struct file *filp, struct kobject *kobj,
1196 				     struct bin_attribute *bin_attr, char *buf,
1197 				     loff_t pos, size_t count)
1198 {
1199 	struct bno055_priv *priv = iio_priv(dev_to_iio_dev(kobj_to_dev(kobj)));
1200 	u8 data[BNO055_CALDATA_LEN];
1201 	int ret;
1202 
1203 	/*
1204 	 * Calibration data is volatile; reading it in chunks will possibly
1205 	 * results in inconsistent data. We require the user to read the whole
1206 	 * blob in a single chunk
1207 	 */
1208 	if (count < BNO055_CALDATA_LEN || pos)
1209 		return -EINVAL;
1210 
1211 	mutex_lock(&priv->lock);
1212 	ret = bno055_operation_mode_do_set(priv, BNO055_OPR_MODE_CONFIG);
1213 	if (ret)
1214 		goto exit_unlock;
1215 
1216 	ret = regmap_bulk_read(priv->regmap, BNO055_CALDATA_START, data,
1217 			       BNO055_CALDATA_LEN);
1218 	if (ret)
1219 		goto exit_unlock;
1220 
1221 	ret = bno055_operation_mode_do_set(priv, priv->operation_mode);
1222 	if (ret)
1223 		goto exit_unlock;
1224 
1225 	memcpy(buf, data, BNO055_CALDATA_LEN);
1226 
1227 	ret = BNO055_CALDATA_LEN;
1228 exit_unlock:
1229 	mutex_unlock(&priv->lock);
1230 	return ret;
1231 }
1232 
1233 static ssize_t sys_calibration_auto_status_show(struct device *dev,
1234 						struct device_attribute *a,
1235 						char *buf)
1236 {
1237 	return bno055_get_calib_status(dev, buf, BNO055_CALIB_STAT_SYS_SHIFT);
1238 }
1239 
1240 static ssize_t in_accel_calibration_auto_status_show(struct device *dev,
1241 						     struct device_attribute *a,
1242 						     char *buf)
1243 {
1244 	return bno055_get_calib_status(dev, buf, BNO055_CALIB_STAT_ACCEL_SHIFT);
1245 }
1246 
1247 static ssize_t in_gyro_calibration_auto_status_show(struct device *dev,
1248 						    struct device_attribute *a,
1249 						    char *buf)
1250 {
1251 	return bno055_get_calib_status(dev, buf, BNO055_CALIB_STAT_GYRO_SHIFT);
1252 }
1253 
1254 static ssize_t in_magn_calibration_auto_status_show(struct device *dev,
1255 						    struct device_attribute *a,
1256 						    char *buf)
1257 {
1258 	return bno055_get_calib_status(dev, buf, BNO055_CALIB_STAT_MAGN_SHIFT);
1259 }
1260 
1261 static int bno055_debugfs_reg_access(struct iio_dev *iio_dev, unsigned int reg,
1262 				     unsigned int writeval, unsigned int *readval)
1263 {
1264 	struct bno055_priv *priv = iio_priv(iio_dev);
1265 
1266 	if (readval)
1267 		return regmap_read(priv->regmap, reg, readval);
1268 	else
1269 		return regmap_write(priv->regmap, reg, writeval);
1270 }
1271 
1272 static ssize_t bno055_show_fw_version(struct file *file, char __user *userbuf,
1273 				      size_t count, loff_t *ppos)
1274 {
1275 	struct bno055_priv *priv = file->private_data;
1276 	int rev, ver;
1277 	char *buf;
1278 	int ret;
1279 
1280 	ret = regmap_read(priv->regmap, BNO055_SW_REV_LSB_REG, &rev);
1281 	if (ret)
1282 		return ret;
1283 
1284 	ret = regmap_read(priv->regmap, BNO055_SW_REV_MSB_REG, &ver);
1285 	if (ret)
1286 		return ret;
1287 
1288 	buf = kasprintf(GFP_KERNEL, "ver: 0x%x, rev: 0x%x\n", ver, rev);
1289 	if (!buf)
1290 		return -ENOMEM;
1291 
1292 	ret = simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
1293 	kfree(buf);
1294 
1295 	return ret;
1296 }
1297 
1298 static const struct file_operations bno055_fw_version_ops = {
1299 	.open = simple_open,
1300 	.read = bno055_show_fw_version,
1301 	.llseek = default_llseek,
1302 	.owner = THIS_MODULE,
1303 };
1304 
1305 static void bno055_debugfs_remove(void *_priv)
1306 {
1307 	struct bno055_priv *priv = _priv;
1308 
1309 	debugfs_remove(priv->debugfs);
1310 	priv->debugfs = NULL;
1311 }
1312 
1313 static void bno055_debugfs_init(struct iio_dev *iio_dev)
1314 {
1315 	struct bno055_priv *priv = iio_priv(iio_dev);
1316 
1317 	priv->debugfs = debugfs_create_file("firmware_version", 0400,
1318 					    iio_get_debugfs_dentry(iio_dev),
1319 					    priv, &bno055_fw_version_ops);
1320 	if (!IS_ERR(priv->debugfs))
1321 		devm_add_action_or_reset(priv->dev, bno055_debugfs_remove,
1322 					 priv);
1323 	if (IS_ERR_OR_NULL(priv->debugfs))
1324 		dev_warn(priv->dev, "failed to setup debugfs");
1325 }
1326 
1327 static IIO_DEVICE_ATTR_RW(fusion_enable, 0);
1328 static IIO_DEVICE_ATTR_RW(in_magn_calibration_fast_enable, 0);
1329 static IIO_DEVICE_ATTR_RW(in_accel_range_raw, 0);
1330 
1331 static IIO_DEVICE_ATTR_RO(in_accel_range_raw_available, 0);
1332 static IIO_DEVICE_ATTR_RO(sys_calibration_auto_status, 0);
1333 static IIO_DEVICE_ATTR_RO(in_accel_calibration_auto_status, 0);
1334 static IIO_DEVICE_ATTR_RO(in_gyro_calibration_auto_status, 0);
1335 static IIO_DEVICE_ATTR_RO(in_magn_calibration_auto_status, 0);
1336 static IIO_DEVICE_ATTR_RO(serialnumber, 0);
1337 
1338 static struct attribute *bno055_attrs[] = {
1339 	&iio_dev_attr_in_accel_range_raw_available.dev_attr.attr,
1340 	&iio_dev_attr_in_accel_range_raw.dev_attr.attr,
1341 	&iio_dev_attr_fusion_enable.dev_attr.attr,
1342 	&iio_dev_attr_in_magn_calibration_fast_enable.dev_attr.attr,
1343 	&iio_dev_attr_sys_calibration_auto_status.dev_attr.attr,
1344 	&iio_dev_attr_in_accel_calibration_auto_status.dev_attr.attr,
1345 	&iio_dev_attr_in_gyro_calibration_auto_status.dev_attr.attr,
1346 	&iio_dev_attr_in_magn_calibration_auto_status.dev_attr.attr,
1347 	&iio_dev_attr_serialnumber.dev_attr.attr,
1348 	NULL
1349 };
1350 
1351 static BIN_ATTR_RO(calibration_data, BNO055_CALDATA_LEN);
1352 
1353 static struct bin_attribute *bno055_bin_attrs[] = {
1354 	&bin_attr_calibration_data,
1355 	NULL
1356 };
1357 
1358 static const struct attribute_group bno055_attrs_group = {
1359 	.attrs = bno055_attrs,
1360 	.bin_attrs = bno055_bin_attrs,
1361 };
1362 
1363 static const struct iio_info bno055_info = {
1364 	.read_raw_multi = bno055_read_raw_multi,
1365 	.read_avail = bno055_read_avail,
1366 	.write_raw = bno055_write_raw,
1367 	.attrs = &bno055_attrs_group,
1368 	.debugfs_reg_access = bno055_debugfs_reg_access,
1369 };
1370 
1371 /*
1372  * Reads len samples from the HW, stores them in buf starting from buf_idx,
1373  * and applies mask to cull (skip) unneeded samples.
1374  * Updates buf_idx incrementing with the number of stored samples.
1375  * Samples from HW are transferred into buf, then in-place copy on buf is
1376  * performed in order to cull samples that need to be skipped.
1377  * This avoids copies of the first samples until we hit the 1st sample to skip,
1378  * and also avoids having an extra bounce buffer.
1379  * buf must be able to contain len elements in spite of how many samples we are
1380  * going to cull.
1381  */
1382 static int bno055_scan_xfer(struct bno055_priv *priv,
1383 			    int start_ch, int len, unsigned long mask,
1384 			    __le16 *buf, int *buf_idx)
1385 {
1386 	const int base = BNO055_ACC_DATA_X_LSB_REG;
1387 	bool quat_in_read = false;
1388 	int buf_base = *buf_idx;
1389 	__le16 *dst, *src;
1390 	int offs_fixup = 0;
1391 	int xfer_len = len;
1392 	int ret;
1393 	int i, n;
1394 
1395 	if (!mask)
1396 		return 0;
1397 
1398 	/*
1399 	 * All channels are made up 1 16-bit sample, except for quaternion that
1400 	 * is made up 4 16-bit values.
1401 	 * For us the quaternion CH is just like 4 regular CHs.
1402 	 * If our read starts past the quaternion make sure to adjust the
1403 	 * starting offset; if the quaternion is contained in our scan then make
1404 	 * sure to adjust the read len.
1405 	 */
1406 	if (start_ch > BNO055_SCAN_QUATERNION) {
1407 		start_ch += 3;
1408 	} else if ((start_ch <= BNO055_SCAN_QUATERNION) &&
1409 		 ((start_ch + len) > BNO055_SCAN_QUATERNION)) {
1410 		quat_in_read = true;
1411 		xfer_len += 3;
1412 	}
1413 
1414 	ret = regmap_bulk_read(priv->regmap,
1415 			       base + start_ch * sizeof(__le16),
1416 			       buf + buf_base,
1417 			       xfer_len * sizeof(__le16));
1418 	if (ret)
1419 		return ret;
1420 
1421 	for_each_set_bit(i, &mask, len) {
1422 		if (quat_in_read && ((start_ch + i) > BNO055_SCAN_QUATERNION))
1423 			offs_fixup = 3;
1424 
1425 		dst = buf + *buf_idx;
1426 		src = buf + buf_base + offs_fixup + i;
1427 
1428 		n = (start_ch + i == BNO055_SCAN_QUATERNION) ? 4 : 1;
1429 
1430 		if (dst != src)
1431 			memcpy(dst, src, n * sizeof(__le16));
1432 
1433 		*buf_idx += n;
1434 	}
1435 	return 0;
1436 }
1437 
1438 static irqreturn_t bno055_trigger_handler(int irq, void *p)
1439 {
1440 	struct iio_poll_func *pf = p;
1441 	struct iio_dev *iio_dev = pf->indio_dev;
1442 	struct bno055_priv *priv = iio_priv(iio_dev);
1443 	int xfer_start, start, end, prev_end;
1444 	unsigned long mask;
1445 	int quat_extra_len;
1446 	bool first = true;
1447 	int buf_idx = 0;
1448 	bool thr_hit;
1449 	int ret;
1450 
1451 	mutex_lock(&priv->lock);
1452 
1453 	/*
1454 	 * Walk the bitmap and eventually perform several transfers.
1455 	 * Bitmap ones-fields that are separated by gaps <= xfer_burst_break_thr
1456 	 * will be included in same transfer.
1457 	 * Every time the bitmap contains a gap wider than xfer_burst_break_thr
1458 	 * then we split the transfer, skipping the gap.
1459 	 */
1460 	for_each_set_bitrange(start, end, iio_dev->active_scan_mask,
1461 			      iio_dev->masklength) {
1462 		/*
1463 		 * First transfer will start from the beginning of the first
1464 		 * ones-field in the bitmap
1465 		 */
1466 		if (first) {
1467 			xfer_start = start;
1468 		} else {
1469 			/*
1470 			 * We found the next ones-field; check whether to
1471 			 * include it in * the current transfer or not (i.e.
1472 			 * let's perform the current * transfer and prepare for
1473 			 * another one).
1474 			 */
1475 
1476 			/*
1477 			 * In case the zeros-gap contains the quaternion bit,
1478 			 * then its length is actually 4 words instead of 1
1479 			 * (i.e. +3 wrt other channels).
1480 			 */
1481 			quat_extra_len = ((start > BNO055_SCAN_QUATERNION) &&
1482 					  (prev_end <= BNO055_SCAN_QUATERNION)) ? 3 : 0;
1483 
1484 			/* If the gap is wider than xfer_burst_break_thr then.. */
1485 			thr_hit = (start - prev_end + quat_extra_len) >
1486 				priv->xfer_burst_break_thr;
1487 
1488 			/*
1489 			 * .. transfer all the data up to the gap. Then set the
1490 			 * next transfer start index at right after the gap
1491 			 * (i.e. at the start of this ones-field).
1492 			 */
1493 			if (thr_hit) {
1494 				mask = *iio_dev->active_scan_mask >> xfer_start;
1495 				ret = bno055_scan_xfer(priv, xfer_start,
1496 						       prev_end - xfer_start,
1497 						       mask, priv->buf.chans, &buf_idx);
1498 				if (ret)
1499 					goto done;
1500 				xfer_start = start;
1501 			}
1502 		}
1503 		first = false;
1504 		prev_end = end;
1505 	}
1506 
1507 	/*
1508 	 * We finished walking the bitmap; no more gaps to check for. Just
1509 	 * perform the current transfer.
1510 	 */
1511 	mask = *iio_dev->active_scan_mask >> xfer_start;
1512 	ret = bno055_scan_xfer(priv, xfer_start,
1513 			       prev_end - xfer_start,
1514 			       mask, priv->buf.chans, &buf_idx);
1515 
1516 	if (!ret)
1517 		iio_push_to_buffers_with_timestamp(iio_dev,
1518 						   &priv->buf, pf->timestamp);
1519 done:
1520 	mutex_unlock(&priv->lock);
1521 	iio_trigger_notify_done(iio_dev->trig);
1522 	return IRQ_HANDLED;
1523 }
1524 
1525 static int bno055_buffer_preenable(struct iio_dev *indio_dev)
1526 {
1527 	struct bno055_priv *priv = iio_priv(indio_dev);
1528 	const unsigned long fusion_mask =
1529 		BIT(BNO055_SCAN_YAW) |
1530 		BIT(BNO055_SCAN_ROLL) |
1531 		BIT(BNO055_SCAN_PITCH) |
1532 		BIT(BNO055_SCAN_QUATERNION) |
1533 		BIT(BNO055_SCAN_LIA_X) |
1534 		BIT(BNO055_SCAN_LIA_Y) |
1535 		BIT(BNO055_SCAN_LIA_Z) |
1536 		BIT(BNO055_SCAN_GRAVITY_X) |
1537 		BIT(BNO055_SCAN_GRAVITY_Y) |
1538 		BIT(BNO055_SCAN_GRAVITY_Z);
1539 
1540 	if (priv->operation_mode == BNO055_OPR_MODE_AMG &&
1541 	    bitmap_intersects(indio_dev->active_scan_mask, &fusion_mask,
1542 			      _BNO055_SCAN_MAX))
1543 		return -EBUSY;
1544 	return 0;
1545 }
1546 
1547 static const struct iio_buffer_setup_ops bno055_buffer_setup_ops = {
1548 	.preenable = bno055_buffer_preenable,
1549 };
1550 
1551 int bno055_probe(struct device *dev, struct regmap *regmap,
1552 		 int xfer_burst_break_thr, bool sw_reset)
1553 {
1554 	const struct firmware *caldata = NULL;
1555 	struct bno055_priv *priv;
1556 	struct iio_dev *iio_dev;
1557 	char *fw_name_buf;
1558 	unsigned int val;
1559 	int rev, ver;
1560 	int ret;
1561 
1562 	iio_dev = devm_iio_device_alloc(dev, sizeof(*priv));
1563 	if (!iio_dev)
1564 		return -ENOMEM;
1565 
1566 	iio_dev->name = "bno055";
1567 	priv = iio_priv(iio_dev);
1568 	mutex_init(&priv->lock);
1569 	priv->regmap = regmap;
1570 	priv->dev = dev;
1571 	priv->xfer_burst_break_thr = xfer_burst_break_thr;
1572 	priv->sw_reset = sw_reset;
1573 
1574 	priv->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1575 	if (IS_ERR(priv->reset_gpio))
1576 		return dev_err_probe(dev, PTR_ERR(priv->reset_gpio), "Failed to get reset GPIO\n");
1577 
1578 	priv->clk = devm_clk_get_optional_enabled(dev, "clk");
1579 	if (IS_ERR(priv->clk))
1580 		return dev_err_probe(dev, PTR_ERR(priv->clk), "Failed to get CLK\n");
1581 
1582 	if (priv->reset_gpio) {
1583 		usleep_range(5000, 10000);
1584 		gpiod_set_value_cansleep(priv->reset_gpio, 1);
1585 		usleep_range(650000, 750000);
1586 	} else if (!sw_reset) {
1587 		dev_warn(dev, "No usable reset method; IMU may be unreliable\n");
1588 	}
1589 
1590 	ret = regmap_read(priv->regmap, BNO055_CHIP_ID_REG, &val);
1591 	if (ret)
1592 		return ret;
1593 
1594 	if (val != BNO055_CHIP_ID_MAGIC)
1595 		dev_warn(dev, "Unrecognized chip ID 0x%x\n", val);
1596 
1597 	/*
1598 	 * In case we haven't a HW reset pin, we can still reset the chip via
1599 	 * register write. This is probably nonsense in case we can't even
1600 	 * communicate with the chip or the chip isn't the one we expect (i.e.
1601 	 * we don't write to unknown chips), so we perform SW reset only after
1602 	 * chip magic ID check
1603 	 */
1604 	if (!priv->reset_gpio) {
1605 		ret = bno055_system_reset(priv);
1606 		if (ret)
1607 			return ret;
1608 	}
1609 
1610 	ret = regmap_read(priv->regmap, BNO055_SW_REV_LSB_REG, &rev);
1611 	if (ret)
1612 		return ret;
1613 
1614 	ret = regmap_read(priv->regmap, BNO055_SW_REV_MSB_REG, &ver);
1615 	if (ret)
1616 		return ret;
1617 
1618 	/*
1619 	 * The stock FW version contains a bug (see comment at the beginning of
1620 	 * this file) that causes the anglvel scale to be changed depending on
1621 	 * the chip range setting. We workaround this, but we don't know what
1622 	 * other FW versions might do.
1623 	 */
1624 	if (ver != 0x3 || rev != 0x11)
1625 		dev_warn(dev, "Untested firmware version. Anglvel scale may not work as expected\n");
1626 
1627 	ret = regmap_bulk_read(priv->regmap, BNO055_UID_LOWER_REG,
1628 			       priv->uid, BNO055_UID_LEN);
1629 	if (ret)
1630 		return ret;
1631 
1632 	/* Sensor calibration data */
1633 	fw_name_buf = kasprintf(GFP_KERNEL, BNO055_FW_UID_FMT,
1634 				BNO055_UID_LEN, priv->uid);
1635 	if (!fw_name_buf)
1636 		return -ENOMEM;
1637 
1638 	ret = request_firmware(&caldata, fw_name_buf, dev);
1639 	kfree(fw_name_buf);
1640 	if (ret)
1641 		ret = request_firmware(&caldata, BNO055_FW_GENERIC_NAME, dev);
1642 	if (ret) {
1643 		dev_notice(dev, "Calibration file load failed. See instruction in kernel Documentation/iio/bno055.rst\n");
1644 		ret = bno055_init(priv, NULL, 0);
1645 	} else {
1646 		ret = bno055_init(priv, caldata->data, caldata->size);
1647 		release_firmware(caldata);
1648 	}
1649 	if (ret)
1650 		return ret;
1651 
1652 	priv->operation_mode = BNO055_OPR_MODE_FUSION;
1653 	ret = bno055_operation_mode_do_set(priv, priv->operation_mode);
1654 	if (ret)
1655 		return ret;
1656 
1657 	ret = devm_add_action_or_reset(dev, bno055_uninit, priv);
1658 	if (ret)
1659 		return ret;
1660 
1661 	iio_dev->channels = bno055_channels;
1662 	iio_dev->num_channels = ARRAY_SIZE(bno055_channels);
1663 	iio_dev->info = &bno055_info;
1664 	iio_dev->modes = INDIO_DIRECT_MODE;
1665 
1666 	ret = devm_iio_triggered_buffer_setup(dev, iio_dev,
1667 					      iio_pollfunc_store_time,
1668 					      bno055_trigger_handler,
1669 					      &bno055_buffer_setup_ops);
1670 	if (ret)
1671 		return ret;
1672 
1673 	ret = devm_iio_device_register(dev, iio_dev);
1674 	if (ret)
1675 		return ret;
1676 
1677 	bno055_debugfs_init(iio_dev);
1678 
1679 	return 0;
1680 }
1681 EXPORT_SYMBOL_NS_GPL(bno055_probe, IIO_BNO055);
1682 
1683 MODULE_AUTHOR("Andrea Merello <andrea.merello@iit.it>");
1684 MODULE_DESCRIPTION("Bosch BNO055 driver");
1685 MODULE_LICENSE("GPL");
1686