drivers/iio/magnetometer/bmc150_magn.c

   1 /*
   2  * Bosch BMC150 three-axis magnetic field sensor driver
   3  *
   4  * Copyright (c) 2015, Intel Corporation.
   5  *
   6  * This code is based on bmm050_api.c authored by contact@bosch.sensortec.com:
   7  *
   8  * (C) Copyright 2011~2014 Bosch Sensortec GmbH All Rights Reserved
   9  *
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms and conditions of the GNU General Public License,
  12  * version 2, as published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope it will be useful, but WITHOUT
  15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  17  * more details.
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/i2c.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/delay.h>
  24 #include <linux/slab.h>
  25 #include <linux/acpi.h>
  26 #include <linux/gpio/consumer.h>
  27 #include <linux/pm.h>
  28 #include <linux/pm_runtime.h>
  29 #include <linux/iio/iio.h>
  30 #include <linux/iio/sysfs.h>
  31 #include <linux/iio/buffer.h>
  32 #include <linux/iio/events.h>
  33 #include <linux/iio/trigger.h>
  34 #include <linux/iio/trigger_consumer.h>
  35 #include <linux/iio/triggered_buffer.h>
  36 #include <linux/regmap.h>
  37
  38 #define BMC150_MAGN_DRV_NAME                    "bmc150_magn"
  39 #define BMC150_MAGN_IRQ_NAME                    "bmc150_magn_event"
  40 #define BMC150_MAGN_GPIO_INT                    "interrupt"
  41
  42 #define BMC150_MAGN_REG_CHIP_ID                 0x40
  43 #define BMC150_MAGN_CHIP_ID_VAL                 0x32
  44
  45 #define BMC150_MAGN_REG_X_L                     0x42
  46 #define BMC150_MAGN_REG_X_M                     0x43
  47 #define BMC150_MAGN_REG_Y_L                     0x44
  48 #define BMC150_MAGN_REG_Y_M                     0x45
  49 #define BMC150_MAGN_SHIFT_XY_L                  3
  50 #define BMC150_MAGN_REG_Z_L                     0x46
  51 #define BMC150_MAGN_REG_Z_M                     0x47
  52 #define BMC150_MAGN_SHIFT_Z_L                   1
  53 #define BMC150_MAGN_REG_RHALL_L                 0x48
  54 #define BMC150_MAGN_REG_RHALL_M                 0x49
  55 #define BMC150_MAGN_SHIFT_RHALL_L               2
  56
  57 #define BMC150_MAGN_REG_INT_STATUS              0x4A
  58
  59 #define BMC150_MAGN_REG_POWER                   0x4B
  60 #define BMC150_MAGN_MASK_POWER_CTL              BIT(0)
  61
  62 #define BMC150_MAGN_REG_OPMODE_ODR              0x4C
  63 #define BMC150_MAGN_MASK_OPMODE                 GENMASK(2, 1)
  64 #define BMC150_MAGN_SHIFT_OPMODE                1
  65 #define BMC150_MAGN_MODE_NORMAL                 0x00
  66 #define BMC150_MAGN_MODE_FORCED                 0x01
  67 #define BMC150_MAGN_MODE_SLEEP                  0x03
  68 #define BMC150_MAGN_MASK_ODR                    GENMASK(5, 3)
  69 #define BMC150_MAGN_SHIFT_ODR                   3
  70
  71 #define BMC150_MAGN_REG_INT                     0x4D
  72
  73 #define BMC150_MAGN_REG_INT_DRDY                0x4E
  74 #define BMC150_MAGN_MASK_DRDY_EN                BIT(7)
  75 #define BMC150_MAGN_SHIFT_DRDY_EN               7
  76 #define BMC150_MAGN_MASK_DRDY_INT3              BIT(6)
  77 #define BMC150_MAGN_MASK_DRDY_Z_EN              BIT(5)
  78 #define BMC150_MAGN_MASK_DRDY_Y_EN              BIT(4)
  79 #define BMC150_MAGN_MASK_DRDY_X_EN              BIT(3)
  80 #define BMC150_MAGN_MASK_DRDY_DR_POLARITY       BIT(2)
  81 #define BMC150_MAGN_MASK_DRDY_LATCHING          BIT(1)
  82 #define BMC150_MAGN_MASK_DRDY_INT3_POLARITY     BIT(0)
  83
  84 #define BMC150_MAGN_REG_LOW_THRESH              0x4F
  85 #define BMC150_MAGN_REG_HIGH_THRESH             0x50
  86 #define BMC150_MAGN_REG_REP_XY                  0x51
  87 #define BMC150_MAGN_REG_REP_Z                   0x52
  88
  89 #define BMC150_MAGN_REG_TRIM_START              0x5D
  90 #define BMC150_MAGN_REG_TRIM_END                0x71
  91
  92 #define BMC150_MAGN_XY_OVERFLOW_VAL             -4096
  93 #define BMC150_MAGN_Z_OVERFLOW_VAL              -16384
  94
  95 /* Time from SUSPEND to SLEEP */
  96 #define BMC150_MAGN_START_UP_TIME_MS            3
  97
  98 #define BMC150_MAGN_AUTO_SUSPEND_DELAY_MS       2000
  99
 100 #define BMC150_MAGN_REGVAL_TO_REPXY(regval) (((regval) * 2) + 1)
 101 #define BMC150_MAGN_REGVAL_TO_REPZ(regval) ((regval) + 1)
 102 #define BMC150_MAGN_REPXY_TO_REGVAL(rep) (((rep) - 1) / 2)
 103 #define BMC150_MAGN_REPZ_TO_REGVAL(rep) ((rep) - 1)
 104
 105 enum bmc150_magn_axis {
 106         AXIS_X,
 107         AXIS_Y,
 108         AXIS_Z,
 109         RHALL,
 110         AXIS_XYZ_MAX = RHALL,
 111         AXIS_XYZR_MAX,
 112 };
 113
 114 enum bmc150_magn_power_modes {
 115         BMC150_MAGN_POWER_MODE_SUSPEND,
 116         BMC150_MAGN_POWER_MODE_SLEEP,
 117         BMC150_MAGN_POWER_MODE_NORMAL,
 118 };
 119
 120 struct bmc150_magn_trim_regs {
 121         s8 x1;
 122         s8 y1;
 123         __le16 reserved1;
 124         u8 reserved2;
 125         __le16 z4;
 126         s8 x2;
 127         s8 y2;
 128         __le16 reserved3;
 129         __le16 z2;
 130         __le16 z1;
 131         __le16 xyz1;
 132         __le16 z3;
 133         s8 xy2;
 134         u8 xy1;
 135 } __packed;
 136
 137 struct bmc150_magn_data {
 138         struct i2c_client *client;
 139         /*
 140          * 1. Protect this structure.
 141          * 2. Serialize sequences that power on/off the device and access HW.
 142          */
 143         struct mutex mutex;
 144         struct regmap *regmap;
 145         /* 4 x 32 bits for x, y z, 4 bytes align, 64 bits timestamp */
 146         s32 buffer[6];
 147         struct iio_trigger *dready_trig;
 148         bool dready_trigger_on;
 149         int max_odr;
 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
 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
 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 static 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
 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
 261 static int bmc150_magn_set_power_state(struct bmc150_magn_data *data, bool on)
 262 {
 263 #ifdef CONFIG_PM
 264         int ret;
 265
 266         if (on) {
 267                 ret = pm_runtime_get_sync(&data->client->dev);
 268         } else {
 269                 pm_runtime_mark_last_busy(&data->client->dev);
 270                 ret = pm_runtime_put_autosuspend(&data->client->dev);
 271         }
 272
 273         if (ret < 0) {
 274                 dev_err(&data->client->dev,
 275                         "failed to change power state to %d\n", on);
 276                 if (on)
 277                         pm_runtime_put_noidle(&data->client->dev);
 278
 279                 return ret;
 280         }
 281 #endif
 282
 283         return 0;
 284 }
 285
 286 static int bmc150_magn_get_odr(struct bmc150_magn_data *data, int *val)
 287 {
 288         int ret, reg_val;
 289         u8 i, odr_val;
 290
 291         ret = regmap_read(data->regmap, BMC150_MAGN_REG_OPMODE_ODR, &reg_val);
 292         if (ret < 0)
 293                 return ret;
 294         odr_val = (reg_val & BMC150_MAGN_MASK_ODR) >> BMC150_MAGN_SHIFT_ODR;
 295
 296         for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++)
 297                 if (bmc150_magn_samp_freq_table[i].reg_val == odr_val) {
 298                         *val = bmc150_magn_samp_freq_table[i].freq;
 299                         return 0;
 300                 }
 301
 302         return -EINVAL;
 303 }
 304
 305 static int bmc150_magn_set_odr(struct bmc150_magn_data *data, int val)
 306 {
 307         int ret;
 308         u8 i;
 309
 310         for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
 311                 if (bmc150_magn_samp_freq_table[i].freq == val) {
 312                         ret = regmap_update_bits(data->regmap,
 313                                                  BMC150_MAGN_REG_OPMODE_ODR,
 314                                                  BMC150_MAGN_MASK_ODR,
 315                                                  bmc150_magn_samp_freq_table[i].
 316                                                  reg_val <<
 317                                                  BMC150_MAGN_SHIFT_ODR);
 318                         if (ret < 0)
 319                                 return ret;
 320                         return 0;
 321                 }
 322         }
 323
 324         return -EINVAL;
 325 }
 326
 327 static int bmc150_magn_set_max_odr(struct bmc150_magn_data *data, int rep_xy,
 328                                    int rep_z, int odr)
 329 {
 330         int ret, reg_val, max_odr;
 331
 332         if (rep_xy <= 0) {
 333                 ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
 334                                   &reg_val);
 335                 if (ret < 0)
 336                         return ret;
 337                 rep_xy = BMC150_MAGN_REGVAL_TO_REPXY(reg_val);
 338         }
 339         if (rep_z <= 0) {
 340                 ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
 341                                   &reg_val);
 342                 if (ret < 0)
 343                         return ret;
 344                 rep_z = BMC150_MAGN_REGVAL_TO_REPZ(reg_val);
 345         }
 346         if (odr <= 0) {
 347                 ret = bmc150_magn_get_odr(data, &odr);
 348                 if (ret < 0)
 349                         return ret;
 350         }
 351         /* the maximum selectable read-out frequency from datasheet */
 352         max_odr = 1000000 / (145 * rep_xy + 500 * rep_z + 980);
 353         if (odr > max_odr) {
 354                 dev_err(&data->client->dev,
 355                         "Can't set oversampling with sampling freq %d\n",
 356                         odr);
 357                 return -EINVAL;
 358         }
 359         data->max_odr = max_odr;
 360
 361         return 0;
 362 }
 363
 364 static s32 bmc150_magn_compensate_x(struct bmc150_magn_trim_regs *tregs, s16 x,
 365                                     u16 rhall)
 366 {
 367         s16 val;
 368         u16 xyz1 = le16_to_cpu(tregs->xyz1);
 369
 370         if (x == BMC150_MAGN_XY_OVERFLOW_VAL)
 371                 return S32_MIN;
 372
 373         if (!rhall)
 374                 rhall = xyz1;
 375
 376         val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
 377         val = ((s16)((((s32)x) * ((((((((s32)tregs->xy2) * ((((s32)val) *
 378               ((s32)val)) >> 7)) + (((s32)val) *
 379               ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
 380               ((s32)(((s16)tregs->x2) + ((s16)0xA0)))) >> 12)) >> 13)) +
 381               (((s16)tregs->x1) << 3);
 382
 383         return (s32)val;
 384 }
 385
 386 static s32 bmc150_magn_compensate_y(struct bmc150_magn_trim_regs *tregs, s16 y,
 387                                     u16 rhall)
 388 {
 389         s16 val;
 390         u16 xyz1 = le16_to_cpu(tregs->xyz1);
 391
 392         if (y == BMC150_MAGN_XY_OVERFLOW_VAL)
 393                 return S32_MIN;
 394
 395         if (!rhall)
 396                 rhall = xyz1;
 397
 398         val = ((s16)(((u16)((((s32)xyz1) << 14) / rhall)) - ((u16)0x4000)));
 399         val = ((s16)((((s32)y) * ((((((((s32)tregs->xy2) * ((((s32)val) *
 400               ((s32)val)) >> 7)) + (((s32)val) *
 401               ((s32)(((s16)tregs->xy1) << 7)))) >> 9) + ((s32)0x100000)) *
 402               ((s32)(((s16)tregs->y2) + ((s16)0xA0)))) >> 12)) >> 13)) +
 403               (((s16)tregs->y1) << 3);
 404
 405         return (s32)val;
 406 }
 407
 408 static s32 bmc150_magn_compensate_z(struct bmc150_magn_trim_regs *tregs, s16 z,
 409                                     u16 rhall)
 410 {
 411         s32 val;
 412         u16 xyz1 = le16_to_cpu(tregs->xyz1);
 413         u16 z1 = le16_to_cpu(tregs->z1);
 414         s16 z2 = le16_to_cpu(tregs->z2);
 415         s16 z3 = le16_to_cpu(tregs->z3);
 416         s16 z4 = le16_to_cpu(tregs->z4);
 417
 418         if (z == BMC150_MAGN_Z_OVERFLOW_VAL)
 419                 return S32_MIN;
 420
 421         val = (((((s32)(z - z4)) << 15) - ((((s32)z3) * ((s32)(((s16)rhall) -
 422               ((s16)xyz1)))) >> 2)) / (z2 + ((s16)(((((s32)z1) *
 423               ((((s16)rhall) << 1))) + (1 << 15)) >> 16))));
 424
 425         return val;
 426 }
 427
 428 static int bmc150_magn_read_xyz(struct bmc150_magn_data *data, s32 *buffer)
 429 {
 430         int ret;
 431         __le16 values[AXIS_XYZR_MAX];
 432         s16 raw_x, raw_y, raw_z;
 433         u16 rhall;
 434         struct bmc150_magn_trim_regs tregs;
 435
 436         ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_X_L,
 437                                values, sizeof(values));
 438         if (ret < 0)
 439                 return ret;
 440
 441         raw_x = (s16)le16_to_cpu(values[AXIS_X]) >> BMC150_MAGN_SHIFT_XY_L;
 442         raw_y = (s16)le16_to_cpu(values[AXIS_Y]) >> BMC150_MAGN_SHIFT_XY_L;
 443         raw_z = (s16)le16_to_cpu(values[AXIS_Z]) >> BMC150_MAGN_SHIFT_Z_L;
 444         rhall = le16_to_cpu(values[RHALL]) >> BMC150_MAGN_SHIFT_RHALL_L;
 445
 446         ret = regmap_bulk_read(data->regmap, BMC150_MAGN_REG_TRIM_START,
 447                                &tregs, sizeof(tregs));
 448         if (ret < 0)
 449                 return ret;
 450
 451         buffer[AXIS_X] = bmc150_magn_compensate_x(&tregs, raw_x, rhall);
 452         buffer[AXIS_Y] = bmc150_magn_compensate_y(&tregs, raw_y, rhall);
 453         buffer[AXIS_Z] = bmc150_magn_compensate_z(&tregs, raw_z, rhall);
 454
 455         return 0;
 456 }
 457
 458 static int bmc150_magn_read_raw(struct iio_dev *indio_dev,
 459                                 struct iio_chan_spec const *chan,
 460                                 int *val, int *val2, long mask)
 461 {
 462         struct bmc150_magn_data *data = iio_priv(indio_dev);
 463         int ret, tmp;
 464         s32 values[AXIS_XYZ_MAX];
 465
 466         switch (mask) {
 467         case IIO_CHAN_INFO_RAW:
 468                 if (iio_buffer_enabled(indio_dev))
 469                         return -EBUSY;
 470                 mutex_lock(&data->mutex);
 471
 472                 ret = bmc150_magn_set_power_state(data, true);
 473                 if (ret < 0) {
 474                         mutex_unlock(&data->mutex);
 475                         return ret;
 476                 }
 477
 478                 ret = bmc150_magn_read_xyz(data, values);
 479                 if (ret < 0) {
 480                         bmc150_magn_set_power_state(data, false);
 481                         mutex_unlock(&data->mutex);
 482                         return ret;
 483                 }
 484                 *val = values[chan->scan_index];
 485
 486                 ret = bmc150_magn_set_power_state(data, false);
 487                 if (ret < 0) {
 488                         mutex_unlock(&data->mutex);
 489                         return ret;
 490                 }
 491
 492                 mutex_unlock(&data->mutex);
 493                 return IIO_VAL_INT;
 494         case IIO_CHAN_INFO_SCALE:
 495                 /*
 496                  * The API/driver performs an off-chip temperature
 497                  * compensation and outputs x/y/z magnetic field data in
 498                  * 16 LSB/uT to the upper application layer.
 499                  */
 500                 *val = 0;
 501                 *val2 = 625;
 502                 return IIO_VAL_INT_PLUS_MICRO;
 503         case IIO_CHAN_INFO_SAMP_FREQ:
 504                 ret = bmc150_magn_get_odr(data, val);
 505                 if (ret < 0)
 506                         return ret;
 507                 return IIO_VAL_INT;
 508         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 509                 switch (chan->channel2) {
 510                 case IIO_MOD_X:
 511                 case IIO_MOD_Y:
 512                         ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_XY,
 513                                           &tmp);
 514                         if (ret < 0)
 515                                 return ret;
 516                         *val = BMC150_MAGN_REGVAL_TO_REPXY(tmp);
 517                         return IIO_VAL_INT;
 518                 case IIO_MOD_Z:
 519                         ret = regmap_read(data->regmap, BMC150_MAGN_REG_REP_Z,
 520                                           &tmp);
 521                         if (ret < 0)
 522                                 return ret;
 523                         *val = BMC150_MAGN_REGVAL_TO_REPZ(tmp);
 524                         return IIO_VAL_INT;
 525                 default:
 526                         return -EINVAL;
 527                 }
 528         default:
 529                 return -EINVAL;
 530         }
 531 }
 532
 533 static int bmc150_magn_write_raw(struct iio_dev *indio_dev,
 534                                  struct iio_chan_spec const *chan,
 535                                  int val, int val2, long mask)
 536 {
 537         struct bmc150_magn_data *data = iio_priv(indio_dev);
 538         int ret;
 539
 540         switch (mask) {
 541         case IIO_CHAN_INFO_SAMP_FREQ:
 542                 if (val > data->max_odr)
 543                         return -EINVAL;
 544                 mutex_lock(&data->mutex);
 545                 ret = bmc150_magn_set_odr(data, val);
 546                 mutex_unlock(&data->mutex);
 547                 return ret;
 548         case IIO_CHAN_INFO_OVERSAMPLING_RATIO:
 549                 switch (chan->channel2) {
 550                 case IIO_MOD_X:
 551                 case IIO_MOD_Y:
 552                         if (val < 1 || val > 511)
 553                                 return -EINVAL;
 554                         mutex_lock(&data->mutex);
 555                         ret = bmc150_magn_set_max_odr(data, val, 0, 0);
 556                         if (ret < 0) {
 557                                 mutex_unlock(&data->mutex);
 558                                 return ret;
 559                         }
 560                         ret = regmap_update_bits(data->regmap,
 561                                                  BMC150_MAGN_REG_REP_XY,
 562                                                  0xFF,
 563                                                  BMC150_MAGN_REPXY_TO_REGVAL
 564                                                  (val));
 565                         mutex_unlock(&data->mutex);
 566                         return ret;
 567                 case IIO_MOD_Z:
 568                         if (val < 1 || val > 256)
 569                                 return -EINVAL;
 570                         mutex_lock(&data->mutex);
 571                         ret = bmc150_magn_set_max_odr(data, 0, val, 0);
 572                         if (ret < 0) {
 573                                 mutex_unlock(&data->mutex);
 574                                 return ret;
 575                         }
 576                         ret = regmap_update_bits(data->regmap,
 577                                                  BMC150_MAGN_REG_REP_Z,
 578                                                  0xFF,
 579                                                  BMC150_MAGN_REPZ_TO_REGVAL
 580                                                  (val));
 581                         mutex_unlock(&data->mutex);
 582                         return ret;
 583                 default:
 584                         return -EINVAL;
 585                 }
 586         default:
 587                 return -EINVAL;
 588         }
 589 }
 590
 591 static int bmc150_magn_validate_trigger(struct iio_dev *indio_dev,
 592                                         struct iio_trigger *trig)
 593 {
 594         struct bmc150_magn_data *data = iio_priv(indio_dev);
 595
 596         if (data->dready_trig != trig)
 597                 return -EINVAL;
 598
 599         return 0;
 600 }
 601
 602 static ssize_t bmc150_magn_show_samp_freq_avail(struct device *dev,
 603                                                 struct device_attribute *attr,
 604                                                 char *buf)
 605 {
 606         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 607         struct bmc150_magn_data *data = iio_priv(indio_dev);
 608         size_t len = 0;
 609         u8 i;
 610
 611         for (i = 0; i < ARRAY_SIZE(bmc150_magn_samp_freq_table); i++) {
 612                 if (bmc150_magn_samp_freq_table[i].freq > data->max_odr)
 613                         break;
 614                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
 615                                  bmc150_magn_samp_freq_table[i].freq);
 616         }
 617         /* replace last space with a newline */
 618         buf[len - 1] = '\n';
 619
 620         return len;
 621 }
 622
 623 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(bmc150_magn_show_samp_freq_avail);
 624
 625 static struct attribute *bmc150_magn_attributes[] = {
 626         &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 627         NULL,
 628 };
 629
 630 static const struct attribute_group bmc150_magn_attrs_group = {
 631         .attrs = bmc150_magn_attributes,
 632 };
 633
 634 #define BMC150_MAGN_CHANNEL(_axis) {                                    \
 635         .type = IIO_MAGN,                                               \
 636         .modified = 1,                                                  \
 637         .channel2 = IIO_MOD_##_axis,                                    \
 638         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |                  \
 639                               BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),    \
 640         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ) |      \
 641                                     BIT(IIO_CHAN_INFO_SCALE),           \
 642         .scan_index = AXIS_##_axis,                                     \
 643         .scan_type = {                                                  \
 644                 .sign = 's',                                            \
 645                 .realbits = 32,                                         \
 646                 .storagebits = 32,                                      \
 647                 .endianness = IIO_LE                                    \
 648         },                                                              \
 649 }
 650
 651 static const struct iio_chan_spec bmc150_magn_channels[] = {
 652         BMC150_MAGN_CHANNEL(X),
 653         BMC150_MAGN_CHANNEL(Y),
 654         BMC150_MAGN_CHANNEL(Z),
 655         IIO_CHAN_SOFT_TIMESTAMP(3),
 656 };
 657
 658 static const struct iio_info bmc150_magn_info = {
 659         .attrs = &bmc150_magn_attrs_group,
 660         .read_raw = bmc150_magn_read_raw,
 661         .write_raw = bmc150_magn_write_raw,
 662         .validate_trigger = bmc150_magn_validate_trigger,
 663         .driver_module = THIS_MODULE,
 664 };
 665
 666 static const unsigned long bmc150_magn_scan_masks[] = {0x07, 0};
 667
 668 static irqreturn_t bmc150_magn_trigger_handler(int irq, void *p)
 669 {
 670         struct iio_poll_func *pf = p;
 671         struct iio_dev *indio_dev = pf->indio_dev;
 672         struct bmc150_magn_data *data = iio_priv(indio_dev);
 673         int ret;
 674
 675         mutex_lock(&data->mutex);
 676         ret = bmc150_magn_read_xyz(data, data->buffer);
 677         mutex_unlock(&data->mutex);
 678         if (ret < 0)
 679                 goto err;
 680
 681         iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 682                                            pf->timestamp);
 683
 684 err:
 685         iio_trigger_notify_done(data->dready_trig);
 686
 687         return IRQ_HANDLED;
 688 }
 689
 690 static int bmc150_magn_init(struct bmc150_magn_data *data)
 691 {
 692         int ret, chip_id;
 693         struct bmc150_magn_preset preset;
 694
 695         ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND,
 696                                          false);
 697         if (ret < 0) {
 698                 dev_err(&data->client->dev,
 699                         "Failed to bring up device from suspend mode\n");
 700                 return ret;
 701         }
 702
 703         ret = regmap_read(data->regmap, BMC150_MAGN_REG_CHIP_ID, &chip_id);
 704         if (ret < 0) {
 705                 dev_err(&data->client->dev, "Failed reading chip id\n");
 706                 goto err_poweroff;
 707         }
 708         if (chip_id != BMC150_MAGN_CHIP_ID_VAL) {
 709                 dev_err(&data->client->dev, "Invalid chip id 0x%x\n", ret);
 710                 ret = -ENODEV;
 711                 goto err_poweroff;
 712         }
 713         dev_dbg(&data->client->dev, "Chip id %x\n", ret);
 714
 715         preset = bmc150_magn_presets_table[BMC150_MAGN_DEFAULT_PRESET];
 716         ret = bmc150_magn_set_odr(data, preset.odr);
 717         if (ret < 0) {
 718                 dev_err(&data->client->dev, "Failed to set ODR to %d\n",
 719                         preset.odr);
 720                 goto err_poweroff;
 721         }
 722
 723         ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_XY,
 724                            BMC150_MAGN_REPXY_TO_REGVAL(preset.rep_xy));
 725         if (ret < 0) {
 726                 dev_err(&data->client->dev, "Failed to set REP XY to %d\n",
 727                         preset.rep_xy);
 728                 goto err_poweroff;
 729         }
 730
 731         ret = regmap_write(data->regmap, BMC150_MAGN_REG_REP_Z,
 732                            BMC150_MAGN_REPZ_TO_REGVAL(preset.rep_z));
 733         if (ret < 0) {
 734                 dev_err(&data->client->dev, "Failed to set REP Z to %d\n",
 735                         preset.rep_z);
 736                 goto err_poweroff;
 737         }
 738
 739         ret = bmc150_magn_set_max_odr(data, preset.rep_xy, preset.rep_z,
 740                                       preset.odr);
 741         if (ret < 0)
 742                 goto err_poweroff;
 743
 744         ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
 745                                          true);
 746         if (ret < 0) {
 747                 dev_err(&data->client->dev, "Failed to power on device\n");
 748                 goto err_poweroff;
 749         }
 750
 751         return 0;
 752
 753 err_poweroff:
 754         bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
 755         return ret;
 756 }
 757
 758 static int bmc150_magn_reset_intr(struct bmc150_magn_data *data)
 759 {
 760         int tmp;
 761
 762         /*
 763          * Data Ready (DRDY) is always cleared after
 764          * readout of data registers ends.
 765          */
 766         return regmap_read(data->regmap, BMC150_MAGN_REG_X_L, &tmp);
 767 }
 768
 769 static int bmc150_magn_trig_try_reen(struct iio_trigger *trig)
 770 {
 771         struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
 772         struct bmc150_magn_data *data = iio_priv(indio_dev);
 773         int ret;
 774
 775         if (!data->dready_trigger_on)
 776                 return 0;
 777
 778         mutex_lock(&data->mutex);
 779         ret = bmc150_magn_reset_intr(data);
 780         mutex_unlock(&data->mutex);
 781
 782         return ret;
 783 }
 784
 785 static int bmc150_magn_data_rdy_trigger_set_state(struct iio_trigger *trig,
 786                                                   bool state)
 787 {
 788         struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
 789         struct bmc150_magn_data *data = iio_priv(indio_dev);
 790         int ret = 0;
 791
 792         mutex_lock(&data->mutex);
 793         if (state == data->dready_trigger_on)
 794                 goto err_unlock;
 795
 796         ret = bmc150_magn_set_power_state(data, state);
 797         if (ret < 0)
 798                 goto err_unlock;
 799
 800         ret = regmap_update_bits(data->regmap, BMC150_MAGN_REG_INT_DRDY,
 801                                  BMC150_MAGN_MASK_DRDY_EN,
 802                                  state << BMC150_MAGN_SHIFT_DRDY_EN);
 803         if (ret < 0)
 804                 goto err_poweroff;
 805
 806         data->dready_trigger_on = state;
 807
 808         if (state) {
 809                 ret = bmc150_magn_reset_intr(data);
 810                 if (ret < 0)
 811                         goto err_poweroff;
 812         }
 813         mutex_unlock(&data->mutex);
 814
 815         return 0;
 816
 817 err_poweroff:
 818         bmc150_magn_set_power_state(data, false);
 819 err_unlock:
 820         mutex_unlock(&data->mutex);
 821         return ret;
 822 }
 823
 824 static const struct iio_trigger_ops bmc150_magn_trigger_ops = {
 825         .set_trigger_state = bmc150_magn_data_rdy_trigger_set_state,
 826         .try_reenable = bmc150_magn_trig_try_reen,
 827         .owner = THIS_MODULE,
 828 };
 829
 830 static int bmc150_magn_gpio_probe(struct i2c_client *client)
 831 {
 832         struct device *dev;
 833         struct gpio_desc *gpio;
 834         int ret;
 835
 836         if (!client)
 837                 return -EINVAL;
 838
 839         dev = &client->dev;
 840
 841         /* data ready GPIO interrupt pin */
 842         gpio = devm_gpiod_get_index(dev, BMC150_MAGN_GPIO_INT, 0);
 843         if (IS_ERR(gpio)) {
 844                 dev_err(dev, "ACPI GPIO get index failed\n");
 845                 return PTR_ERR(gpio);
 846         }
 847
 848         ret = gpiod_direction_input(gpio);
 849         if (ret)
 850                 return ret;
 851
 852         ret = gpiod_to_irq(gpio);
 853
 854         dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
 855
 856         return ret;
 857 }
 858
 859 static const char *bmc150_magn_match_acpi_device(struct device *dev)
 860 {
 861         const struct acpi_device_id *id;
 862
 863         id = acpi_match_device(dev->driver->acpi_match_table, dev);
 864         if (!id)
 865                 return NULL;
 866
 867         return dev_name(dev);
 868 }
 869
 870 static int bmc150_magn_probe(struct i2c_client *client,
 871                              const struct i2c_device_id *id)
 872 {
 873         struct bmc150_magn_data *data;
 874         struct iio_dev *indio_dev;
 875         const char *name = NULL;
 876         int ret;
 877
 878         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 879         if (!indio_dev)
 880                 return -ENOMEM;
 881
 882         data = iio_priv(indio_dev);
 883         i2c_set_clientdata(client, indio_dev);
 884         data->client = client;
 885
 886         if (id)
 887                 name = id->name;
 888         else if (ACPI_HANDLE(&client->dev))
 889                 name = bmc150_magn_match_acpi_device(&client->dev);
 890         else
 891                 return -ENOSYS;
 892
 893         mutex_init(&data->mutex);
 894         data->regmap = devm_regmap_init_i2c(client, &bmc150_magn_regmap_config);
 895         if (IS_ERR(data->regmap)) {
 896                 dev_err(&client->dev, "Failed to allocate register map\n");
 897                 return PTR_ERR(data->regmap);
 898         }
 899
 900         ret = bmc150_magn_init(data);
 901         if (ret < 0)
 902                 return ret;
 903
 904         indio_dev->dev.parent = &client->dev;
 905         indio_dev->channels = bmc150_magn_channels;
 906         indio_dev->num_channels = ARRAY_SIZE(bmc150_magn_channels);
 907         indio_dev->available_scan_masks = bmc150_magn_scan_masks;
 908         indio_dev->name = name;
 909         indio_dev->modes = INDIO_DIRECT_MODE;
 910         indio_dev->info = &bmc150_magn_info;
 911
 912         if (client->irq <= 0)
 913                 client->irq = bmc150_magn_gpio_probe(client);
 914
 915         if (client->irq > 0) {
 916                 data->dready_trig = devm_iio_trigger_alloc(&client->dev,
 917                                                            "%s-dev%d",
 918                                                            indio_dev->name,
 919                                                            indio_dev->id);
 920                 if (!data->dready_trig) {
 921                         ret = -ENOMEM;
 922                         dev_err(&client->dev, "iio trigger alloc failed\n");
 923                         goto err_poweroff;
 924                 }
 925
 926                 data->dready_trig->dev.parent = &client->dev;
 927                 data->dready_trig->ops = &bmc150_magn_trigger_ops;
 928                 iio_trigger_set_drvdata(data->dready_trig, indio_dev);
 929                 ret = iio_trigger_register(data->dready_trig);
 930                 if (ret) {
 931                         dev_err(&client->dev, "iio trigger register failed\n");
 932                         goto err_poweroff;
 933                 }
 934
 935                 ret = iio_triggered_buffer_setup(indio_dev,
 936                                                  &iio_pollfunc_store_time,
 937                                                  bmc150_magn_trigger_handler,
 938                                                  NULL);
 939                 if (ret < 0) {
 940                         dev_err(&client->dev,
 941                                 "iio triggered buffer setup failed\n");
 942                         goto err_trigger_unregister;
 943                 }
 944
 945                 ret = request_threaded_irq(client->irq,
 946                                            iio_trigger_generic_data_rdy_poll,
 947                                            NULL,
 948                                            IRQF_TRIGGER_RISING | IRQF_ONESHOT,
 949                                            BMC150_MAGN_IRQ_NAME,
 950                                            data->dready_trig);
 951                 if (ret < 0) {
 952                         dev_err(&client->dev, "request irq %d failed\n",
 953                                 client->irq);
 954                         goto err_buffer_cleanup;
 955                 }
 956         }
 957
 958         ret = iio_device_register(indio_dev);
 959         if (ret < 0) {
 960                 dev_err(&client->dev, "unable to register iio device\n");
 961                 goto err_free_irq;
 962         }
 963
 964         ret = pm_runtime_set_active(&client->dev);
 965         if (ret)
 966                 goto err_iio_unregister;
 967
 968         pm_runtime_enable(&client->dev);
 969         pm_runtime_set_autosuspend_delay(&client->dev,
 970                                          BMC150_MAGN_AUTO_SUSPEND_DELAY_MS);
 971         pm_runtime_use_autosuspend(&client->dev);
 972
 973         dev_dbg(&indio_dev->dev, "Registered device %s\n", name);
 974
 975         return 0;
 976
 977 err_iio_unregister:
 978         iio_device_unregister(indio_dev);
 979 err_free_irq:
 980         if (client->irq > 0)
 981                 free_irq(client->irq, data->dready_trig);
 982 err_buffer_cleanup:
 983         if (data->dready_trig)
 984                 iio_triggered_buffer_cleanup(indio_dev);
 985 err_trigger_unregister:
 986         if (data->dready_trig)
 987                 iio_trigger_unregister(data->dready_trig);
 988 err_poweroff:
 989         bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
 990         return ret;
 991 }
 992
 993 static int bmc150_magn_remove(struct i2c_client *client)
 994 {
 995         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 996         struct bmc150_magn_data *data = iio_priv(indio_dev);
 997
 998         pm_runtime_disable(&client->dev);
 999         pm_runtime_set_suspended(&client->dev);
1000         pm_runtime_put_noidle(&client->dev);
1001
1002         iio_device_unregister(indio_dev);
1003
1004         if (client->irq > 0)
1005                 free_irq(data->client->irq, data->dready_trig);
1006
1007         if (data->dready_trig) {
1008                 iio_triggered_buffer_cleanup(indio_dev);
1009                 iio_trigger_unregister(data->dready_trig);
1010         }
1011
1012         mutex_lock(&data->mutex);
1013         bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SUSPEND, true);
1014         mutex_unlock(&data->mutex);
1015
1016         return 0;
1017 }
1018
1019 #ifdef CONFIG_PM
1020 static int bmc150_magn_runtime_suspend(struct device *dev)
1021 {
1022         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1023         struct bmc150_magn_data *data = iio_priv(indio_dev);
1024         int ret;
1025
1026         mutex_lock(&data->mutex);
1027         ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
1028                                          true);
1029         mutex_unlock(&data->mutex);
1030         if (ret < 0) {
1031                 dev_err(&data->client->dev, "powering off device failed\n");
1032                 return ret;
1033         }
1034         return 0;
1035 }
1036
1037 static int bmc150_magn_runtime_resume(struct device *dev)
1038 {
1039         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1040         struct bmc150_magn_data *data = iio_priv(indio_dev);
1041
1042         return bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
1043                                           true);
1044 }
1045 #endif
1046
1047 #ifdef CONFIG_PM_SLEEP
1048 static int bmc150_magn_suspend(struct device *dev)
1049 {
1050         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1051         struct bmc150_magn_data *data = iio_priv(indio_dev);
1052         int ret;
1053
1054         mutex_lock(&data->mutex);
1055         ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_SLEEP,
1056                                          true);
1057         mutex_unlock(&data->mutex);
1058
1059         return ret;
1060 }
1061
1062 static int bmc150_magn_resume(struct device *dev)
1063 {
1064         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1065         struct bmc150_magn_data *data = iio_priv(indio_dev);
1066         int ret;
1067
1068         mutex_lock(&data->mutex);
1069         ret = bmc150_magn_set_power_mode(data, BMC150_MAGN_POWER_MODE_NORMAL,
1070                                          true);
1071         mutex_unlock(&data->mutex);
1072
1073         return ret;
1074 }
1075 #endif
1076
1077 static const struct dev_pm_ops bmc150_magn_pm_ops = {
1078         SET_SYSTEM_SLEEP_PM_OPS(bmc150_magn_suspend, bmc150_magn_resume)
1079         SET_RUNTIME_PM_OPS(bmc150_magn_runtime_suspend,
1080                            bmc150_magn_runtime_resume, NULL)
1081 };
1082
1083 static const struct acpi_device_id bmc150_magn_acpi_match[] = {
1084         {"BMC150B", 0},
1085         {},
1086 };
1087 MODULE_DEVICE_TABLE(acpi, bmc150_magn_acpi_match);
1088
1089 static const struct i2c_device_id bmc150_magn_id[] = {
1090         {"bmc150_magn", 0},
1091         {},
1092 };
1093 MODULE_DEVICE_TABLE(i2c, bmc150_magn_id);
1094
1095 static struct i2c_driver bmc150_magn_driver = {
1096         .driver = {
1097                    .name = BMC150_MAGN_DRV_NAME,
1098                    .acpi_match_table = ACPI_PTR(bmc150_magn_acpi_match),
1099                    .pm = &bmc150_magn_pm_ops,
1100                    },
1101         .probe = bmc150_magn_probe,
1102         .remove = bmc150_magn_remove,
1103         .id_table = bmc150_magn_id,
1104 };
1105 module_i2c_driver(bmc150_magn_driver);
1106
1107 MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
1108 MODULE_LICENSE("GPL v2");
1109 MODULE_DESCRIPTION("BMC150 magnetometer driver");