kernel/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 <asm/unaligned.h>
  19 #include <linux/iio/common/st_sensors.h>
  20
  21
  22 #define ST_SENSORS_WAI_ADDRESS          0x0f
  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 static 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         err = st_sensors_match_odr(sdata->sensor_settings, odr, &odr_out);
  97         if (err < 0)
  98                 goto st_sensors_match_odr_error;
  99
 100         if ((sdata->sensor_settings->odr.addr ==
 101                                         sdata->sensor_settings->pw.addr) &&
 102                                 (sdata->sensor_settings->odr.mask ==
 103                                         sdata->sensor_settings->pw.mask)) {
 104                 if (sdata->enabled == true) {
 105                         err = st_sensors_write_data_with_mask(indio_dev,
 106                                 sdata->sensor_settings->odr.addr,
 107                                 sdata->sensor_settings->odr.mask,
 108                                 odr_out.value);
 109                 } else {
 110                         err = 0;
 111                 }
 112         } else {
 113                 err = st_sensors_write_data_with_mask(indio_dev,
 114                         sdata->sensor_settings->odr.addr,
 115                         sdata->sensor_settings->odr.mask,
 116                         odr_out.value);
 117         }
 118         if (err >= 0)
 119                 sdata->odr = odr_out.hz;
 120
 121 st_sensors_match_odr_error:
 122         return err;
 123 }
 124 EXPORT_SYMBOL(st_sensors_set_odr);
 125
 126 static int st_sensors_match_fs(struct st_sensor_settings *sensor_settings,
 127                                         unsigned int fs, int *index_fs_avl)
 128 {
 129         int i, ret = -EINVAL;
 130
 131         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 132                 if (sensor_settings->fs.fs_avl[i].num == 0)
 133                         goto st_sensors_match_odr_error;
 134
 135                 if (sensor_settings->fs.fs_avl[i].num == fs) {
 136                         *index_fs_avl = i;
 137                         ret = 0;
 138                         break;
 139                 }
 140         }
 141
 142 st_sensors_match_odr_error:
 143         return ret;
 144 }
 145
 146 static int st_sensors_set_fullscale(struct iio_dev *indio_dev, unsigned int fs)
 147 {
 148         int err, i = 0;
 149         struct st_sensor_data *sdata = iio_priv(indio_dev);
 150
 151         if (sdata->sensor_settings->fs.addr == 0)
 152                 return 0;
 153
 154         err = st_sensors_match_fs(sdata->sensor_settings, fs, &i);
 155         if (err < 0)
 156                 goto st_accel_set_fullscale_error;
 157
 158         err = st_sensors_write_data_with_mask(indio_dev,
 159                                 sdata->sensor_settings->fs.addr,
 160                                 sdata->sensor_settings->fs.mask,
 161                                 sdata->sensor_settings->fs.fs_avl[i].value);
 162         if (err < 0)
 163                 goto st_accel_set_fullscale_error;
 164
 165         sdata->current_fullscale = (struct st_sensor_fullscale_avl *)
 166                                         &sdata->sensor_settings->fs.fs_avl[i];
 167         return err;
 168
 169 st_accel_set_fullscale_error:
 170         dev_err(&indio_dev->dev, "failed to set new fullscale.\n");
 171         return err;
 172 }
 173
 174 int st_sensors_set_enable(struct iio_dev *indio_dev, bool enable)
 175 {
 176         u8 tmp_value;
 177         int err = -EINVAL;
 178         bool found = false;
 179         struct st_sensor_odr_avl odr_out = {0, 0};
 180         struct st_sensor_data *sdata = iio_priv(indio_dev);
 181
 182         if (enable) {
 183                 tmp_value = sdata->sensor_settings->pw.value_on;
 184                 if ((sdata->sensor_settings->odr.addr ==
 185                                         sdata->sensor_settings->pw.addr) &&
 186                                 (sdata->sensor_settings->odr.mask ==
 187                                         sdata->sensor_settings->pw.mask)) {
 188                         err = st_sensors_match_odr(sdata->sensor_settings,
 189                                                         sdata->odr, &odr_out);
 190                         if (err < 0)
 191                                 goto set_enable_error;
 192                         tmp_value = odr_out.value;
 193                         found = true;
 194                 }
 195                 err = st_sensors_write_data_with_mask(indio_dev,
 196                                 sdata->sensor_settings->pw.addr,
 197                                 sdata->sensor_settings->pw.mask, tmp_value);
 198                 if (err < 0)
 199                         goto set_enable_error;
 200
 201                 sdata->enabled = true;
 202
 203                 if (found)
 204                         sdata->odr = odr_out.hz;
 205         } else {
 206                 err = st_sensors_write_data_with_mask(indio_dev,
 207                                 sdata->sensor_settings->pw.addr,
 208                                 sdata->sensor_settings->pw.mask,
 209                                 sdata->sensor_settings->pw.value_off);
 210                 if (err < 0)
 211                         goto set_enable_error;
 212
 213                 sdata->enabled = false;
 214         }
 215
 216 set_enable_error:
 217         return err;
 218 }
 219 EXPORT_SYMBOL(st_sensors_set_enable);
 220
 221 int st_sensors_set_axis_enable(struct iio_dev *indio_dev, u8 axis_enable)
 222 {
 223         struct st_sensor_data *sdata = iio_priv(indio_dev);
 224
 225         return st_sensors_write_data_with_mask(indio_dev,
 226                                 sdata->sensor_settings->enable_axis.addr,
 227                                 sdata->sensor_settings->enable_axis.mask,
 228                                 axis_enable);
 229 }
 230 EXPORT_SYMBOL(st_sensors_set_axis_enable);
 231
 232 void st_sensors_power_enable(struct iio_dev *indio_dev)
 233 {
 234         struct st_sensor_data *pdata = iio_priv(indio_dev);
 235         int err;
 236
 237         /* Regulators not mandatory, but if requested we should enable them. */
 238         pdata->vdd = devm_regulator_get_optional(indio_dev->dev.parent, "vdd");
 239         if (!IS_ERR(pdata->vdd)) {
 240                 err = regulator_enable(pdata->vdd);
 241                 if (err != 0)
 242                         dev_warn(&indio_dev->dev,
 243                                  "Failed to enable specified Vdd supply\n");
 244         }
 245
 246         pdata->vdd_io = devm_regulator_get_optional(indio_dev->dev.parent, "vddio");
 247         if (!IS_ERR(pdata->vdd_io)) {
 248                 err = regulator_enable(pdata->vdd_io);
 249                 if (err != 0)
 250                         dev_warn(&indio_dev->dev,
 251                                  "Failed to enable specified Vdd_IO supply\n");
 252         }
 253 }
 254 EXPORT_SYMBOL(st_sensors_power_enable);
 255
 256 void st_sensors_power_disable(struct iio_dev *indio_dev)
 257 {
 258         struct st_sensor_data *pdata = iio_priv(indio_dev);
 259
 260         if (!IS_ERR(pdata->vdd))
 261                 regulator_disable(pdata->vdd);
 262
 263         if (!IS_ERR(pdata->vdd_io))
 264                 regulator_disable(pdata->vdd_io);
 265 }
 266 EXPORT_SYMBOL(st_sensors_power_disable);
 267
 268 static int st_sensors_set_drdy_int_pin(struct iio_dev *indio_dev,
 269                                         struct st_sensors_platform_data *pdata)
 270 {
 271         struct st_sensor_data *sdata = iio_priv(indio_dev);
 272
 273         /* Sensor does not support interrupts */
 274         if (sdata->sensor_settings->drdy_irq.addr == 0) {
 275                 if (pdata->drdy_int_pin)
 276                         dev_info(&indio_dev->dev,
 277                                  "DRDY on pin INT%d specified, but sensor "
 278                                  "does not support interrupts\n",
 279                                  pdata->drdy_int_pin);
 280                 return 0;
 281         }
 282
 283         switch (pdata->drdy_int_pin) {
 284         case 1:
 285                 if (sdata->sensor_settings->drdy_irq.mask_int1 == 0) {
 286                         dev_err(&indio_dev->dev,
 287                                         "DRDY on INT1 not available.\n");
 288                         return -EINVAL;
 289                 }
 290                 sdata->drdy_int_pin = 1;
 291                 break;
 292         case 2:
 293                 if (sdata->sensor_settings->drdy_irq.mask_int2 == 0) {
 294                         dev_err(&indio_dev->dev,
 295                                         "DRDY on INT2 not available.\n");
 296                         return -EINVAL;
 297                 }
 298                 sdata->drdy_int_pin = 2;
 299                 break;
 300         default:
 301                 dev_err(&indio_dev->dev, "DRDY on pdata not valid.\n");
 302                 return -EINVAL;
 303         }
 304
 305         return 0;
 306 }
 307
 308 #ifdef CONFIG_OF
 309 static struct st_sensors_platform_data *st_sensors_of_probe(struct device *dev,
 310                 struct st_sensors_platform_data *defdata)
 311 {
 312         struct st_sensors_platform_data *pdata;
 313         struct device_node *np = dev->of_node;
 314         u32 val;
 315
 316         if (!np)
 317                 return NULL;
 318
 319         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 320         if (!of_property_read_u32(np, "st,drdy-int-pin", &val) && (val <= 2))
 321                 pdata->drdy_int_pin = (u8) val;
 322         else
 323                 pdata->drdy_int_pin = defdata ? defdata->drdy_int_pin : 0;
 324
 325         return pdata;
 326 }
 327 #else
 328 static struct st_sensors_platform_data *st_sensors_of_probe(struct device *dev,
 329                 struct st_sensors_platform_data *defdata)
 330 {
 331         return NULL;
 332 }
 333 #endif
 334
 335 int st_sensors_init_sensor(struct iio_dev *indio_dev,
 336                                         struct st_sensors_platform_data *pdata)
 337 {
 338         struct st_sensor_data *sdata = iio_priv(indio_dev);
 339         struct st_sensors_platform_data *of_pdata;
 340         int err = 0;
 341
 342         /* If OF/DT pdata exists, it will take precedence of anything else */
 343         of_pdata = st_sensors_of_probe(indio_dev->dev.parent, pdata);
 344         if (of_pdata)
 345                 pdata = of_pdata;
 346
 347         if (pdata) {
 348                 err = st_sensors_set_drdy_int_pin(indio_dev, pdata);
 349                 if (err < 0)
 350                         return err;
 351         }
 352
 353         err = st_sensors_set_enable(indio_dev, false);
 354         if (err < 0)
 355                 return err;
 356
 357         if (sdata->current_fullscale) {
 358                 err = st_sensors_set_fullscale(indio_dev,
 359                                                 sdata->current_fullscale->num);
 360                 if (err < 0)
 361                         return err;
 362         } else
 363                 dev_info(&indio_dev->dev, "Full-scale not possible\n");
 364
 365         err = st_sensors_set_odr(indio_dev, sdata->odr);
 366         if (err < 0)
 367                 return err;
 368
 369         /* set BDU */
 370         if (sdata->sensor_settings->bdu.addr) {
 371                 err = st_sensors_write_data_with_mask(indio_dev,
 372                                         sdata->sensor_settings->bdu.addr,
 373                                         sdata->sensor_settings->bdu.mask, true);
 374                 if (err < 0)
 375                         return err;
 376         }
 377
 378         err = st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
 379
 380         return err;
 381 }
 382 EXPORT_SYMBOL(st_sensors_init_sensor);
 383
 384 int st_sensors_set_dataready_irq(struct iio_dev *indio_dev, bool enable)
 385 {
 386         int err;
 387         u8 drdy_mask;
 388         struct st_sensor_data *sdata = iio_priv(indio_dev);
 389
 390         if (!sdata->sensor_settings->drdy_irq.addr)
 391                 return 0;
 392
 393         /* Enable/Disable the interrupt generator 1. */
 394         if (sdata->sensor_settings->drdy_irq.ig1.en_addr > 0) {
 395                 err = st_sensors_write_data_with_mask(indio_dev,
 396                                 sdata->sensor_settings->drdy_irq.ig1.en_addr,
 397                                 sdata->sensor_settings->drdy_irq.ig1.en_mask,
 398                                 (int)enable);
 399                 if (err < 0)
 400                         goto st_accel_set_dataready_irq_error;
 401         }
 402
 403         if (sdata->drdy_int_pin == 1)
 404                 drdy_mask = sdata->sensor_settings->drdy_irq.mask_int1;
 405         else
 406                 drdy_mask = sdata->sensor_settings->drdy_irq.mask_int2;
 407
 408         /* Enable/Disable the interrupt generator for data ready. */
 409         err = st_sensors_write_data_with_mask(indio_dev,
 410                                         sdata->sensor_settings->drdy_irq.addr,
 411                                         drdy_mask, (int)enable);
 412
 413 st_accel_set_dataready_irq_error:
 414         return err;
 415 }
 416 EXPORT_SYMBOL(st_sensors_set_dataready_irq);
 417
 418 int st_sensors_set_fullscale_by_gain(struct iio_dev *indio_dev, int scale)
 419 {
 420         int err = -EINVAL, i;
 421         struct st_sensor_data *sdata = iio_priv(indio_dev);
 422
 423         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 424                 if ((sdata->sensor_settings->fs.fs_avl[i].gain == scale) &&
 425                                 (sdata->sensor_settings->fs.fs_avl[i].gain != 0)) {
 426                         err = 0;
 427                         break;
 428                 }
 429         }
 430         if (err < 0)
 431                 goto st_sensors_match_scale_error;
 432
 433         err = st_sensors_set_fullscale(indio_dev,
 434                                 sdata->sensor_settings->fs.fs_avl[i].num);
 435
 436 st_sensors_match_scale_error:
 437         return err;
 438 }
 439 EXPORT_SYMBOL(st_sensors_set_fullscale_by_gain);
 440
 441 static int st_sensors_read_axis_data(struct iio_dev *indio_dev,
 442                                 struct iio_chan_spec const *ch, int *data)
 443 {
 444         int err;
 445         u8 *outdata;
 446         struct st_sensor_data *sdata = iio_priv(indio_dev);
 447         unsigned int byte_for_channel = ch->scan_type.storagebits >> 3;
 448
 449         outdata = kmalloc(byte_for_channel, GFP_KERNEL);
 450         if (!outdata)
 451                 return -ENOMEM;
 452
 453         err = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
 454                                 ch->address, byte_for_channel,
 455                                 outdata, sdata->multiread_bit);
 456         if (err < 0)
 457                 goto st_sensors_free_memory;
 458
 459         if (byte_for_channel == 1)
 460                 *data = (s8)*outdata;
 461         else if (byte_for_channel == 2)
 462                 *data = (s16)get_unaligned_le16(outdata);
 463         else if (byte_for_channel == 3)
 464                 *data = (s32)st_sensors_get_unaligned_le24(outdata);
 465
 466 st_sensors_free_memory:
 467         kfree(outdata);
 468
 469         return err;
 470 }
 471
 472 int st_sensors_read_info_raw(struct iio_dev *indio_dev,
 473                                 struct iio_chan_spec const *ch, int *val)
 474 {
 475         int err;
 476         struct st_sensor_data *sdata = iio_priv(indio_dev);
 477
 478         mutex_lock(&indio_dev->mlock);
 479         if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
 480                 err = -EBUSY;
 481                 goto out;
 482         } else {
 483                 err = st_sensors_set_enable(indio_dev, true);
 484                 if (err < 0)
 485                         goto out;
 486
 487                 msleep((sdata->sensor_settings->bootime * 1000) / sdata->odr);
 488                 err = st_sensors_read_axis_data(indio_dev, ch, val);
 489                 if (err < 0)
 490                         goto out;
 491
 492                 *val = *val >> ch->scan_type.shift;
 493
 494                 err = st_sensors_set_enable(indio_dev, false);
 495         }
 496 out:
 497         mutex_unlock(&indio_dev->mlock);
 498
 499         return err;
 500 }
 501 EXPORT_SYMBOL(st_sensors_read_info_raw);
 502
 503 int st_sensors_check_device_support(struct iio_dev *indio_dev,
 504                         int num_sensors_list,
 505                         const struct st_sensor_settings *sensor_settings)
 506 {
 507         int i, n, err;
 508         u8 wai;
 509         struct st_sensor_data *sdata = iio_priv(indio_dev);
 510
 511         for (i = 0; i < num_sensors_list; i++) {
 512                 for (n = 0; n < ST_SENSORS_MAX_4WAI; n++) {
 513                         if (strcmp(indio_dev->name,
 514                                 sensor_settings[i].sensors_supported[n]) == 0) {
 515                                 break;
 516                         }
 517                 }
 518                 if (n < ST_SENSORS_MAX_4WAI)
 519                         break;
 520         }
 521         if (i == num_sensors_list) {
 522                 dev_err(&indio_dev->dev, "device name %s not recognized.\n",
 523                                                         indio_dev->name);
 524                 return -ENODEV;
 525         }
 526
 527         err = sdata->tf->read_byte(&sdata->tb, sdata->dev,
 528                                         sensor_settings[i].wai_addr, &wai);
 529         if (err < 0) {
 530                 dev_err(&indio_dev->dev, "failed to read Who-Am-I register.\n");
 531                 return err;
 532         }
 533
 534         if (sensor_settings[i].wai != wai) {
 535                 dev_err(&indio_dev->dev, "%s: WhoAmI mismatch (0x%x).\n",
 536                                                 indio_dev->name, wai);
 537                 return -EINVAL;
 538         }
 539
 540         sdata->sensor_settings =
 541                         (struct st_sensor_settings *)&sensor_settings[i];
 542
 543         return i;
 544 }
 545 EXPORT_SYMBOL(st_sensors_check_device_support);
 546
 547 ssize_t st_sensors_sysfs_sampling_frequency_avail(struct device *dev,
 548                                 struct device_attribute *attr, char *buf)
 549 {
 550         int i, len = 0;
 551         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 552         struct st_sensor_data *sdata = iio_priv(indio_dev);
 553
 554         mutex_lock(&indio_dev->mlock);
 555         for (i = 0; i < ST_SENSORS_ODR_LIST_MAX; i++) {
 556                 if (sdata->sensor_settings->odr.odr_avl[i].hz == 0)
 557                         break;
 558
 559                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
 560                                 sdata->sensor_settings->odr.odr_avl[i].hz);
 561         }
 562         mutex_unlock(&indio_dev->mlock);
 563         buf[len - 1] = '\n';
 564
 565         return len;
 566 }
 567 EXPORT_SYMBOL(st_sensors_sysfs_sampling_frequency_avail);
 568
 569 ssize_t st_sensors_sysfs_scale_avail(struct device *dev,
 570                                 struct device_attribute *attr, char *buf)
 571 {
 572         int i, len = 0;
 573         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 574         struct st_sensor_data *sdata = iio_priv(indio_dev);
 575
 576         mutex_lock(&indio_dev->mlock);
 577         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 578                 if (sdata->sensor_settings->fs.fs_avl[i].num == 0)
 579                         break;
 580
 581                 len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06u ",
 582                                 sdata->sensor_settings->fs.fs_avl[i].gain);
 583         }
 584         mutex_unlock(&indio_dev->mlock);
 585         buf[len - 1] = '\n';
 586
 587         return len;
 588 }
 589 EXPORT_SYMBOL(st_sensors_sysfs_scale_avail);
 590
 591 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 592 MODULE_DESCRIPTION("STMicroelectronics ST-sensors core");
 593 MODULE_LICENSE("GPL v2");