drivers/iio/common/st_sensors/st_sensors_core.c

   1 /*
   2  * STMicroelectronics sensors core library driver
   3  *
   4  * Copyright 2012-2013 STMicroelectronics Inc.
   5  *
   6  * Denis Ciocca <denis.ciocca@st.com>
   7  *
   8  * Licensed under the GPL-2.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/delay.h>
  15 #include <linux/iio/iio.h>
  16 #include <linux/regulator/consumer.h>
  17 #include <linux/of.h>
  18 #include <linux/of_device.h>
  19 #include <asm/unaligned.h>
  20 #include <linux/iio/common/st_sensors.h>
  21
  22 #include "st_sensors_core.h"
  23
  24 static inline u32 st_sensors_get_unaligned_le24(const u8 *p)
  25 {
  26         return (s32)((p[0] | p[1] << 8 | p[2] << 16) << 8) >> 8;
  27 }
  28
  29 int st_sensors_write_data_with_mask(struct iio_dev *indio_dev,
  30                                     u8 reg_addr, u8 mask, u8 data)
  31 {
  32         int err;
  33         u8 new_data;
  34         struct st_sensor_data *sdata = iio_priv(indio_dev);
  35
  36         err = sdata->tf->read_byte(&sdata->tb, sdata->dev, reg_addr, &new_data);
  37         if (err < 0)
  38                 goto st_sensors_write_data_with_mask_error;
  39
  40         new_data = ((new_data & (~mask)) | ((data << __ffs(mask)) & mask));
  41         err = sdata->tf->write_byte(&sdata->tb, sdata->dev, reg_addr, new_data);
  42
  43 st_sensors_write_data_with_mask_error:
  44         return err;
  45 }
  46
  47 int st_sensors_debugfs_reg_access(struct iio_dev *indio_dev,
  48                                   unsigned reg, unsigned writeval,
  49                                   unsigned *readval)
  50 {
  51         struct st_sensor_data *sdata = iio_priv(indio_dev);
  52         u8 readdata;
  53         int err;
  54
  55         if (!readval)
  56                 return sdata->tf->write_byte(&sdata->tb, sdata->dev,
  57                                              (u8)reg, (u8)writeval);
  58
  59         err = sdata->tf->read_byte(&sdata->tb, sdata->dev, (u8)reg, &readdata);
  60         if (err < 0)
  61                 return err;
  62
  63         *readval = (unsigned)readdata;
  64
  65         return 0;
  66 }
  67 EXPORT_SYMBOL(st_sensors_debugfs_reg_access);
  68
  69 static int st_sensors_match_odr(struct st_sensor_settings *sensor_settings,
  70                         unsigned int odr, struct st_sensor_odr_avl *odr_out)
  71 {
  72         int i, ret = -EINVAL;
  73
  74         for (i = 0; i < ST_SENSORS_ODR_LIST_MAX; i++) {
  75                 if (sensor_settings->odr.odr_avl[i].hz == 0)
  76                         goto st_sensors_match_odr_error;
  77
  78                 if (sensor_settings->odr.odr_avl[i].hz == odr) {
  79                         odr_out->hz = sensor_settings->odr.odr_avl[i].hz;
  80                         odr_out->value = sensor_settings->odr.odr_avl[i].value;
  81                         ret = 0;
  82                         break;
  83                 }
  84         }
  85
  86 st_sensors_match_odr_error:
  87         return ret;
  88 }
  89
  90 int st_sensors_set_odr(struct iio_dev *indio_dev, unsigned int odr)
  91 {
  92         int err;
  93         struct st_sensor_odr_avl odr_out = {0, 0};
  94         struct st_sensor_data *sdata = iio_priv(indio_dev);
  95
  96         if (!sdata->sensor_settings->odr.addr)
  97                 return 0;
  98
  99         err = st_sensors_match_odr(sdata->sensor_settings, odr, &odr_out);
 100         if (err < 0)
 101                 goto st_sensors_match_odr_error;
 102
 103         if ((sdata->sensor_settings->odr.addr ==
 104                                         sdata->sensor_settings->pw.addr) &&
 105                                 (sdata->sensor_settings->odr.mask ==
 106                                         sdata->sensor_settings->pw.mask)) {
 107                 if (sdata->enabled == true) {
 108                         err = st_sensors_write_data_with_mask(indio_dev,
 109                                 sdata->sensor_settings->odr.addr,
 110                                 sdata->sensor_settings->odr.mask,
 111                                 odr_out.value);
 112                 } else {
 113                         err = 0;
 114                 }
 115         } else {
 116                 err = st_sensors_write_data_with_mask(indio_dev,
 117                         sdata->sensor_settings->odr.addr,
 118                         sdata->sensor_settings->odr.mask,
 119                         odr_out.value);
 120         }
 121         if (err >= 0)
 122                 sdata->odr = odr_out.hz;
 123
 124 st_sensors_match_odr_error:
 125         return err;
 126 }
 127 EXPORT_SYMBOL(st_sensors_set_odr);
 128
 129 static int st_sensors_match_fs(struct st_sensor_settings *sensor_settings,
 130                                         unsigned int fs, int *index_fs_avl)
 131 {
 132         int i, ret = -EINVAL;
 133
 134         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 135                 if (sensor_settings->fs.fs_avl[i].num == 0)
 136                         goto st_sensors_match_odr_error;
 137
 138                 if (sensor_settings->fs.fs_avl[i].num == fs) {
 139                         *index_fs_avl = i;
 140                         ret = 0;
 141                         break;
 142                 }
 143         }
 144
 145 st_sensors_match_odr_error:
 146         return ret;
 147 }
 148
 149 static int st_sensors_set_fullscale(struct iio_dev *indio_dev, unsigned int fs)
 150 {
 151         int err, i = 0;
 152         struct st_sensor_data *sdata = iio_priv(indio_dev);
 153
 154         if (sdata->sensor_settings->fs.addr == 0)
 155                 return 0;
 156
 157         err = st_sensors_match_fs(sdata->sensor_settings, fs, &i);
 158         if (err < 0)
 159                 goto st_accel_set_fullscale_error;
 160
 161         err = st_sensors_write_data_with_mask(indio_dev,
 162                                 sdata->sensor_settings->fs.addr,
 163                                 sdata->sensor_settings->fs.mask,
 164                                 sdata->sensor_settings->fs.fs_avl[i].value);
 165         if (err < 0)
 166                 goto st_accel_set_fullscale_error;
 167
 168         sdata->current_fullscale = (struct st_sensor_fullscale_avl *)
 169                                         &sdata->sensor_settings->fs.fs_avl[i];
 170         return err;
 171
 172 st_accel_set_fullscale_error:
 173         dev_err(&indio_dev->dev, "failed to set new fullscale.\n");
 174         return err;
 175 }
 176
 177 int st_sensors_set_enable(struct iio_dev *indio_dev, bool enable)
 178 {
 179         u8 tmp_value;
 180         int err = -EINVAL;
 181         bool found = false;
 182         struct st_sensor_odr_avl odr_out = {0, 0};
 183         struct st_sensor_data *sdata = iio_priv(indio_dev);
 184
 185         if (enable) {
 186                 tmp_value = sdata->sensor_settings->pw.value_on;
 187                 if ((sdata->sensor_settings->odr.addr ==
 188                                         sdata->sensor_settings->pw.addr) &&
 189                                 (sdata->sensor_settings->odr.mask ==
 190                                         sdata->sensor_settings->pw.mask)) {
 191                         err = st_sensors_match_odr(sdata->sensor_settings,
 192                                                         sdata->odr, &odr_out);
 193                         if (err < 0)
 194                                 goto set_enable_error;
 195                         tmp_value = odr_out.value;
 196                         found = true;
 197                 }
 198                 err = st_sensors_write_data_with_mask(indio_dev,
 199                                 sdata->sensor_settings->pw.addr,
 200                                 sdata->sensor_settings->pw.mask, tmp_value);
 201                 if (err < 0)
 202                         goto set_enable_error;
 203
 204                 sdata->enabled = true;
 205
 206                 if (found)
 207                         sdata->odr = odr_out.hz;
 208         } else {
 209                 err = st_sensors_write_data_with_mask(indio_dev,
 210                                 sdata->sensor_settings->pw.addr,
 211                                 sdata->sensor_settings->pw.mask,
 212                                 sdata->sensor_settings->pw.value_off);
 213                 if (err < 0)
 214                         goto set_enable_error;
 215
 216                 sdata->enabled = false;
 217         }
 218
 219 set_enable_error:
 220         return err;
 221 }
 222 EXPORT_SYMBOL(st_sensors_set_enable);
 223
 224 int st_sensors_set_axis_enable(struct iio_dev *indio_dev, u8 axis_enable)
 225 {
 226         struct st_sensor_data *sdata = iio_priv(indio_dev);
 227         int err = 0;
 228
 229         if (sdata->sensor_settings->enable_axis.addr)
 230                 err = st_sensors_write_data_with_mask(indio_dev,
 231                                 sdata->sensor_settings->enable_axis.addr,
 232                                 sdata->sensor_settings->enable_axis.mask,
 233                                 axis_enable);
 234         return err;
 235 }
 236 EXPORT_SYMBOL(st_sensors_set_axis_enable);
 237
 238 int st_sensors_power_enable(struct iio_dev *indio_dev)
 239 {
 240         struct st_sensor_data *pdata = iio_priv(indio_dev);
 241         int err;
 242
 243         /* Regulators not mandatory, but if requested we should enable them. */
 244         pdata->vdd = devm_regulator_get(indio_dev->dev.parent, "vdd");
 245         if (IS_ERR(pdata->vdd)) {
 246                 dev_err(&indio_dev->dev, "unable to get Vdd supply\n");
 247                 return PTR_ERR(pdata->vdd);
 248         }
 249         err = regulator_enable(pdata->vdd);
 250         if (err != 0) {
 251                 dev_warn(&indio_dev->dev,
 252                          "Failed to enable specified Vdd supply\n");
 253                 return err;
 254         }
 255
 256         pdata->vdd_io = devm_regulator_get(indio_dev->dev.parent, "vddio");
 257         if (IS_ERR(pdata->vdd_io)) {
 258                 dev_err(&indio_dev->dev, "unable to get Vdd_IO supply\n");
 259                 err = PTR_ERR(pdata->vdd_io);
 260                 goto st_sensors_disable_vdd;
 261         }
 262         err = regulator_enable(pdata->vdd_io);
 263         if (err != 0) {
 264                 dev_warn(&indio_dev->dev,
 265                          "Failed to enable specified Vdd_IO supply\n");
 266                 goto st_sensors_disable_vdd;
 267         }
 268
 269         return 0;
 270
 271 st_sensors_disable_vdd:
 272         regulator_disable(pdata->vdd);
 273         return err;
 274 }
 275 EXPORT_SYMBOL(st_sensors_power_enable);
 276
 277 void st_sensors_power_disable(struct iio_dev *indio_dev)
 278 {
 279         struct st_sensor_data *pdata = iio_priv(indio_dev);
 280
 281         regulator_disable(pdata->vdd);
 282         regulator_disable(pdata->vdd_io);
 283 }
 284 EXPORT_SYMBOL(st_sensors_power_disable);
 285
 286 static int st_sensors_set_drdy_int_pin(struct iio_dev *indio_dev,
 287                                         struct st_sensors_platform_data *pdata)
 288 {
 289         struct st_sensor_data *sdata = iio_priv(indio_dev);
 290
 291         /* Sensor does not support interrupts */
 292         if (!sdata->sensor_settings->drdy_irq.int1.addr &&
 293             !sdata->sensor_settings->drdy_irq.int2.addr) {
 294                 if (pdata->drdy_int_pin)
 295                         dev_info(&indio_dev->dev,
 296                                  "DRDY on pin INT%d specified, but sensor "
 297                                  "does not support interrupts\n",
 298                                  pdata->drdy_int_pin);
 299                 return 0;
 300         }
 301
 302         switch (pdata->drdy_int_pin) {
 303         case 1:
 304                 if (!sdata->sensor_settings->drdy_irq.int1.mask) {
 305                         dev_err(&indio_dev->dev,
 306                                         "DRDY on INT1 not available.\n");
 307                         return -EINVAL;
 308                 }
 309                 sdata->drdy_int_pin = 1;
 310                 break;
 311         case 2:
 312                 if (!sdata->sensor_settings->drdy_irq.int2.mask) {
 313                         dev_err(&indio_dev->dev,
 314                                         "DRDY on INT2 not available.\n");
 315                         return -EINVAL;
 316                 }
 317                 sdata->drdy_int_pin = 2;
 318                 break;
 319         default:
 320                 dev_err(&indio_dev->dev, "DRDY on pdata not valid.\n");
 321                 return -EINVAL;
 322         }
 323
 324         if (pdata->open_drain) {
 325                 if (!sdata->sensor_settings->drdy_irq.int1.addr_od &&
 326                     !sdata->sensor_settings->drdy_irq.int2.addr_od)
 327                         dev_err(&indio_dev->dev,
 328                                 "open drain requested but unsupported.\n");
 329                 else
 330                         sdata->int_pin_open_drain = true;
 331         }
 332
 333         return 0;
 334 }
 335
 336 #ifdef CONFIG_OF
 337 static struct st_sensors_platform_data *st_sensors_of_probe(struct device *dev,
 338                 struct st_sensors_platform_data *defdata)
 339 {
 340         struct st_sensors_platform_data *pdata;
 341         struct device_node *np = dev->of_node;
 342         u32 val;
 343
 344         if (!np)
 345                 return NULL;
 346
 347         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 348         if (!of_property_read_u32(np, "st,drdy-int-pin", &val) && (val <= 2))
 349                 pdata->drdy_int_pin = (u8) val;
 350         else
 351                 pdata->drdy_int_pin = defdata ? defdata->drdy_int_pin : 0;
 352
 353         pdata->open_drain = of_property_read_bool(np, "drive-open-drain");
 354
 355         return pdata;
 356 }
 357
 358 /**
 359  * st_sensors_of_name_probe() - device tree probe for ST sensor name
 360  * @dev: driver model representation of the device.
 361  * @match: the OF match table for the device, containing compatible strings
 362  *      but also a .data field with the corresponding internal kernel name
 363  *      used by this sensor.
 364  * @name: device name buffer reference.
 365  * @len: device name buffer length.
 366  *
 367  * In effect this function matches a compatible string to an internal kernel
 368  * name for a certain sensor device, so that the rest of the autodetection can
 369  * rely on that name from this point on. I2C/SPI devices will be renamed
 370  * to match the internal kernel convention.
 371  */
 372 void st_sensors_of_name_probe(struct device *dev,
 373                               const struct of_device_id *match,
 374                               char *name, int len)
 375 {
 376         const struct of_device_id *of_id;
 377
 378         of_id = of_match_device(match, dev);
 379         if (!of_id || !of_id->data)
 380                 return;
 381
 382         /* The name from the OF match takes precedence if present */
 383         strlcpy(name, of_id->data, len);
 384 }
 385 EXPORT_SYMBOL(st_sensors_of_name_probe);
 386 #else
 387 static struct st_sensors_platform_data *st_sensors_of_probe(struct device *dev,
 388                 struct st_sensors_platform_data *defdata)
 389 {
 390         return NULL;
 391 }
 392 #endif
 393
 394 int st_sensors_init_sensor(struct iio_dev *indio_dev,
 395                                         struct st_sensors_platform_data *pdata)
 396 {
 397         struct st_sensor_data *sdata = iio_priv(indio_dev);
 398         struct st_sensors_platform_data *of_pdata;
 399         int err = 0;
 400
 401         /* If OF/DT pdata exists, it will take precedence of anything else */
 402         of_pdata = st_sensors_of_probe(indio_dev->dev.parent, pdata);
 403         if (of_pdata)
 404                 pdata = of_pdata;
 405
 406         if (pdata) {
 407                 err = st_sensors_set_drdy_int_pin(indio_dev, pdata);
 408                 if (err < 0)
 409                         return err;
 410         }
 411
 412         err = st_sensors_set_enable(indio_dev, false);
 413         if (err < 0)
 414                 return err;
 415
 416         /* Disable DRDY, this might be still be enabled after reboot. */
 417         err = st_sensors_set_dataready_irq(indio_dev, false);
 418         if (err < 0)
 419                 return err;
 420
 421         if (sdata->current_fullscale) {
 422                 err = st_sensors_set_fullscale(indio_dev,
 423                                                 sdata->current_fullscale->num);
 424                 if (err < 0)
 425                         return err;
 426         } else
 427                 dev_info(&indio_dev->dev, "Full-scale not possible\n");
 428
 429         err = st_sensors_set_odr(indio_dev, sdata->odr);
 430         if (err < 0)
 431                 return err;
 432
 433         /* set BDU */
 434         if (sdata->sensor_settings->bdu.addr) {
 435                 err = st_sensors_write_data_with_mask(indio_dev,
 436                                         sdata->sensor_settings->bdu.addr,
 437                                         sdata->sensor_settings->bdu.mask, true);
 438                 if (err < 0)
 439                         return err;
 440         }
 441
 442         /* set DAS */
 443         if (sdata->sensor_settings->das.addr) {
 444                 err = st_sensors_write_data_with_mask(indio_dev,
 445                                         sdata->sensor_settings->das.addr,
 446                                         sdata->sensor_settings->das.mask, 1);
 447                 if (err < 0)
 448                         return err;
 449         }
 450
 451         if (sdata->int_pin_open_drain) {
 452                 u8 addr, mask;
 453
 454                 if (sdata->drdy_int_pin == 1) {
 455                         addr = sdata->sensor_settings->drdy_irq.int1.addr_od;
 456                         mask = sdata->sensor_settings->drdy_irq.int1.mask_od;
 457                 } else {
 458                         addr = sdata->sensor_settings->drdy_irq.int2.addr_od;
 459                         mask = sdata->sensor_settings->drdy_irq.int2.mask_od;
 460                 }
 461
 462                 dev_info(&indio_dev->dev,
 463                          "set interrupt line to open drain mode on pin %d\n",
 464                          sdata->drdy_int_pin);
 465                 err = st_sensors_write_data_with_mask(indio_dev, addr,
 466                                                       mask, 1);
 467                 if (err < 0)
 468                         return err;
 469         }
 470
 471         err = st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
 472
 473         return err;
 474 }
 475 EXPORT_SYMBOL(st_sensors_init_sensor);
 476
 477 int st_sensors_set_dataready_irq(struct iio_dev *indio_dev, bool enable)
 478 {
 479         int err;
 480         u8 drdy_addr, drdy_mask;
 481         struct st_sensor_data *sdata = iio_priv(indio_dev);
 482
 483         if (!sdata->sensor_settings->drdy_irq.int1.addr &&
 484             !sdata->sensor_settings->drdy_irq.int2.addr) {
 485                 /*
 486                  * there are some devices (e.g. LIS3MDL) where drdy line is
 487                  * routed to a given pin and it is not possible to select a
 488                  * different one. Take into account irq status register
 489                  * to understand if irq trigger can be properly supported
 490                  */
 491                 if (sdata->sensor_settings->drdy_irq.stat_drdy.addr)
 492                         sdata->hw_irq_trigger = enable;
 493                 return 0;
 494         }
 495
 496         /* Enable/Disable the interrupt generator 1. */
 497         if (sdata->sensor_settings->drdy_irq.ig1.en_addr > 0) {
 498                 err = st_sensors_write_data_with_mask(indio_dev,
 499                                 sdata->sensor_settings->drdy_irq.ig1.en_addr,
 500                                 sdata->sensor_settings->drdy_irq.ig1.en_mask,
 501                                 (int)enable);
 502                 if (err < 0)
 503                         goto st_accel_set_dataready_irq_error;
 504         }
 505
 506         if (sdata->drdy_int_pin == 1) {
 507                 drdy_addr = sdata->sensor_settings->drdy_irq.int1.addr;
 508                 drdy_mask = sdata->sensor_settings->drdy_irq.int1.mask;
 509         } else {
 510                 drdy_addr = sdata->sensor_settings->drdy_irq.int2.addr;
 511                 drdy_mask = sdata->sensor_settings->drdy_irq.int2.mask;
 512         }
 513
 514         /* Flag to the poll function that the hardware trigger is in use */
 515         sdata->hw_irq_trigger = enable;
 516
 517         /* Enable/Disable the interrupt generator for data ready. */
 518         err = st_sensors_write_data_with_mask(indio_dev, drdy_addr,
 519                                               drdy_mask, (int)enable);
 520
 521 st_accel_set_dataready_irq_error:
 522         return err;
 523 }
 524 EXPORT_SYMBOL(st_sensors_set_dataready_irq);
 525
 526 int st_sensors_set_fullscale_by_gain(struct iio_dev *indio_dev, int scale)
 527 {
 528         int err = -EINVAL, i;
 529         struct st_sensor_data *sdata = iio_priv(indio_dev);
 530
 531         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 532                 if ((sdata->sensor_settings->fs.fs_avl[i].gain == scale) &&
 533                                 (sdata->sensor_settings->fs.fs_avl[i].gain != 0)) {
 534                         err = 0;
 535                         break;
 536                 }
 537         }
 538         if (err < 0)
 539                 goto st_sensors_match_scale_error;
 540
 541         err = st_sensors_set_fullscale(indio_dev,
 542                                 sdata->sensor_settings->fs.fs_avl[i].num);
 543
 544 st_sensors_match_scale_error:
 545         return err;
 546 }
 547 EXPORT_SYMBOL(st_sensors_set_fullscale_by_gain);
 548
 549 static int st_sensors_read_axis_data(struct iio_dev *indio_dev,
 550                                 struct iio_chan_spec const *ch, int *data)
 551 {
 552         int err;
 553         u8 *outdata;
 554         struct st_sensor_data *sdata = iio_priv(indio_dev);
 555         unsigned int byte_for_channel;
 556
 557         byte_for_channel = DIV_ROUND_UP(ch->scan_type.realbits +
 558                                         ch->scan_type.shift, 8);
 559         outdata = kmalloc(byte_for_channel, GFP_KERNEL);
 560         if (!outdata)
 561                 return -ENOMEM;
 562
 563         err = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
 564                                 ch->address, byte_for_channel,
 565                                 outdata, sdata->multiread_bit);
 566         if (err < 0)
 567                 goto st_sensors_free_memory;
 568
 569         if (byte_for_channel == 1)
 570                 *data = (s8)*outdata;
 571         else if (byte_for_channel == 2)
 572                 *data = (s16)get_unaligned_le16(outdata);
 573         else if (byte_for_channel == 3)
 574                 *data = (s32)st_sensors_get_unaligned_le24(outdata);
 575
 576 st_sensors_free_memory:
 577         kfree(outdata);
 578
 579         return err;
 580 }
 581
 582 int st_sensors_read_info_raw(struct iio_dev *indio_dev,
 583                                 struct iio_chan_spec const *ch, int *val)
 584 {
 585         int err;
 586         struct st_sensor_data *sdata = iio_priv(indio_dev);
 587
 588         mutex_lock(&indio_dev->mlock);
 589         if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
 590                 err = -EBUSY;
 591                 goto out;
 592         } else {
 593                 err = st_sensors_set_enable(indio_dev, true);
 594                 if (err < 0)
 595                         goto out;
 596
 597                 msleep((sdata->sensor_settings->bootime * 1000) / sdata->odr);
 598                 err = st_sensors_read_axis_data(indio_dev, ch, val);
 599                 if (err < 0)
 600                         goto out;
 601
 602                 *val = *val >> ch->scan_type.shift;
 603
 604                 err = st_sensors_set_enable(indio_dev, false);
 605         }
 606 out:
 607         mutex_unlock(&indio_dev->mlock);
 608
 609         return err;
 610 }
 611 EXPORT_SYMBOL(st_sensors_read_info_raw);
 612
 613 static int st_sensors_init_interface_mode(struct iio_dev *indio_dev,
 614                         const struct st_sensor_settings *sensor_settings)
 615 {
 616         struct st_sensor_data *sdata = iio_priv(indio_dev);
 617         struct device_node *np = sdata->dev->of_node;
 618         struct st_sensors_platform_data *pdata;
 619
 620         pdata = (struct st_sensors_platform_data *)sdata->dev->platform_data;
 621         if (((np && of_property_read_bool(np, "spi-3wire")) ||
 622              (pdata && pdata->spi_3wire)) && sensor_settings->sim.addr) {
 623                 int err;
 624
 625                 err = sdata->tf->write_byte(&sdata->tb, sdata->dev,
 626                                             sensor_settings->sim.addr,
 627                                             sensor_settings->sim.value);
 628                 if (err < 0) {
 629                         dev_err(&indio_dev->dev,
 630                                 "failed to init interface mode\n");
 631                         return err;
 632                 }
 633         }
 634
 635         return 0;
 636 }
 637
 638 int st_sensors_check_device_support(struct iio_dev *indio_dev,
 639                         int num_sensors_list,
 640                         const struct st_sensor_settings *sensor_settings)
 641 {
 642         int i, n, err = 0;
 643         u8 wai;
 644         struct st_sensor_data *sdata = iio_priv(indio_dev);
 645
 646         for (i = 0; i < num_sensors_list; i++) {
 647                 for (n = 0; n < ST_SENSORS_MAX_4WAI; n++) {
 648                         if (strcmp(indio_dev->name,
 649                                 sensor_settings[i].sensors_supported[n]) == 0) {
 650                                 break;
 651                         }
 652                 }
 653                 if (n < ST_SENSORS_MAX_4WAI)
 654                         break;
 655         }
 656         if (i == num_sensors_list) {
 657                 dev_err(&indio_dev->dev, "device name %s not recognized.\n",
 658                                                         indio_dev->name);
 659                 return -ENODEV;
 660         }
 661
 662         err = st_sensors_init_interface_mode(indio_dev, &sensor_settings[i]);
 663         if (err < 0)
 664                 return err;
 665
 666         if (sensor_settings[i].wai_addr) {
 667                 err = sdata->tf->read_byte(&sdata->tb, sdata->dev,
 668                                            sensor_settings[i].wai_addr, &wai);
 669                 if (err < 0) {
 670                         dev_err(&indio_dev->dev,
 671                                 "failed to read Who-Am-I register.\n");
 672                         return err;
 673                 }
 674
 675                 if (sensor_settings[i].wai != wai) {
 676                         dev_err(&indio_dev->dev,
 677                                 "%s: WhoAmI mismatch (0x%x).\n",
 678                                 indio_dev->name, wai);
 679                         return -EINVAL;
 680                 }
 681         }
 682
 683         sdata->sensor_settings =
 684                         (struct st_sensor_settings *)&sensor_settings[i];
 685
 686         return i;
 687 }
 688 EXPORT_SYMBOL(st_sensors_check_device_support);
 689
 690 ssize_t st_sensors_sysfs_sampling_frequency_avail(struct device *dev,
 691                                 struct device_attribute *attr, char *buf)
 692 {
 693         int i, len = 0;
 694         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 695         struct st_sensor_data *sdata = iio_priv(indio_dev);
 696
 697         mutex_lock(&indio_dev->mlock);
 698         for (i = 0; i < ST_SENSORS_ODR_LIST_MAX; i++) {
 699                 if (sdata->sensor_settings->odr.odr_avl[i].hz == 0)
 700                         break;
 701
 702                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
 703                                 sdata->sensor_settings->odr.odr_avl[i].hz);
 704         }
 705         mutex_unlock(&indio_dev->mlock);
 706         buf[len - 1] = '\n';
 707
 708         return len;
 709 }
 710 EXPORT_SYMBOL(st_sensors_sysfs_sampling_frequency_avail);
 711
 712 ssize_t st_sensors_sysfs_scale_avail(struct device *dev,
 713                                 struct device_attribute *attr, char *buf)
 714 {
 715         int i, len = 0, q, r;
 716         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 717         struct st_sensor_data *sdata = iio_priv(indio_dev);
 718
 719         mutex_lock(&indio_dev->mlock);
 720         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 721                 if (sdata->sensor_settings->fs.fs_avl[i].num == 0)
 722                         break;
 723
 724                 q = sdata->sensor_settings->fs.fs_avl[i].gain / 1000000;
 725                 r = sdata->sensor_settings->fs.fs_avl[i].gain % 1000000;
 726
 727                 len += scnprintf(buf + len, PAGE_SIZE - len, "%u.%06u ", q, r);
 728         }
 729         mutex_unlock(&indio_dev->mlock);
 730         buf[len - 1] = '\n';
 731
 732         return len;
 733 }
 734 EXPORT_SYMBOL(st_sensors_sysfs_scale_avail);
 735
 736 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 737 MODULE_DESCRIPTION("STMicroelectronics ST-sensors core");
 738 MODULE_LICENSE("GPL v2");