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 static int st_sensors_match_odr(struct st_sensor_settings *sensor_settings,
  48                         unsigned int odr, struct st_sensor_odr_avl *odr_out)
  49 {
  50         int i, ret = -EINVAL;
  51
  52         for (i = 0; i < ST_SENSORS_ODR_LIST_MAX; i++) {
  53                 if (sensor_settings->odr.odr_avl[i].hz == 0)
  54                         goto st_sensors_match_odr_error;
  55
  56                 if (sensor_settings->odr.odr_avl[i].hz == odr) {
  57                         odr_out->hz = sensor_settings->odr.odr_avl[i].hz;
  58                         odr_out->value = sensor_settings->odr.odr_avl[i].value;
  59                         ret = 0;
  60                         break;
  61                 }
  62         }
  63
  64 st_sensors_match_odr_error:
  65         return ret;
  66 }
  67
  68 int st_sensors_set_odr(struct iio_dev *indio_dev, unsigned int odr)
  69 {
  70         int err;
  71         struct st_sensor_odr_avl odr_out = {0, 0};
  72         struct st_sensor_data *sdata = iio_priv(indio_dev);
  73
  74         err = st_sensors_match_odr(sdata->sensor_settings, odr, &odr_out);
  75         if (err < 0)
  76                 goto st_sensors_match_odr_error;
  77
  78         if ((sdata->sensor_settings->odr.addr ==
  79                                         sdata->sensor_settings->pw.addr) &&
  80                                 (sdata->sensor_settings->odr.mask ==
  81                                         sdata->sensor_settings->pw.mask)) {
  82                 if (sdata->enabled == true) {
  83                         err = st_sensors_write_data_with_mask(indio_dev,
  84                                 sdata->sensor_settings->odr.addr,
  85                                 sdata->sensor_settings->odr.mask,
  86                                 odr_out.value);
  87                 } else {
  88                         err = 0;
  89                 }
  90         } else {
  91                 err = st_sensors_write_data_with_mask(indio_dev,
  92                         sdata->sensor_settings->odr.addr,
  93                         sdata->sensor_settings->odr.mask,
  94                         odr_out.value);
  95         }
  96         if (err >= 0)
  97                 sdata->odr = odr_out.hz;
  98
  99 st_sensors_match_odr_error:
 100         return err;
 101 }
 102 EXPORT_SYMBOL(st_sensors_set_odr);
 103
 104 static int st_sensors_match_fs(struct st_sensor_settings *sensor_settings,
 105                                         unsigned int fs, int *index_fs_avl)
 106 {
 107         int i, ret = -EINVAL;
 108
 109         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 110                 if (sensor_settings->fs.fs_avl[i].num == 0)
 111                         goto st_sensors_match_odr_error;
 112
 113                 if (sensor_settings->fs.fs_avl[i].num == fs) {
 114                         *index_fs_avl = i;
 115                         ret = 0;
 116                         break;
 117                 }
 118         }
 119
 120 st_sensors_match_odr_error:
 121         return ret;
 122 }
 123
 124 static int st_sensors_set_fullscale(struct iio_dev *indio_dev, unsigned int fs)
 125 {
 126         int err, i = 0;
 127         struct st_sensor_data *sdata = iio_priv(indio_dev);
 128
 129         err = st_sensors_match_fs(sdata->sensor_settings, fs, &i);
 130         if (err < 0)
 131                 goto st_accel_set_fullscale_error;
 132
 133         err = st_sensors_write_data_with_mask(indio_dev,
 134                                 sdata->sensor_settings->fs.addr,
 135                                 sdata->sensor_settings->fs.mask,
 136                                 sdata->sensor_settings->fs.fs_avl[i].value);
 137         if (err < 0)
 138                 goto st_accel_set_fullscale_error;
 139
 140         sdata->current_fullscale = (struct st_sensor_fullscale_avl *)
 141                                         &sdata->sensor_settings->fs.fs_avl[i];
 142         return err;
 143
 144 st_accel_set_fullscale_error:
 145         dev_err(&indio_dev->dev, "failed to set new fullscale.\n");
 146         return err;
 147 }
 148
 149 int st_sensors_set_enable(struct iio_dev *indio_dev, bool enable)
 150 {
 151         u8 tmp_value;
 152         int err = -EINVAL;
 153         bool found = false;
 154         struct st_sensor_odr_avl odr_out = {0, 0};
 155         struct st_sensor_data *sdata = iio_priv(indio_dev);
 156
 157         if (enable) {
 158                 tmp_value = sdata->sensor_settings->pw.value_on;
 159                 if ((sdata->sensor_settings->odr.addr ==
 160                                         sdata->sensor_settings->pw.addr) &&
 161                                 (sdata->sensor_settings->odr.mask ==
 162                                         sdata->sensor_settings->pw.mask)) {
 163                         err = st_sensors_match_odr(sdata->sensor_settings,
 164                                                         sdata->odr, &odr_out);
 165                         if (err < 0)
 166                                 goto set_enable_error;
 167                         tmp_value = odr_out.value;
 168                         found = true;
 169                 }
 170                 err = st_sensors_write_data_with_mask(indio_dev,
 171                                 sdata->sensor_settings->pw.addr,
 172                                 sdata->sensor_settings->pw.mask, tmp_value);
 173                 if (err < 0)
 174                         goto set_enable_error;
 175
 176                 sdata->enabled = true;
 177
 178                 if (found)
 179                         sdata->odr = odr_out.hz;
 180         } else {
 181                 err = st_sensors_write_data_with_mask(indio_dev,
 182                                 sdata->sensor_settings->pw.addr,
 183                                 sdata->sensor_settings->pw.mask,
 184                                 sdata->sensor_settings->pw.value_off);
 185                 if (err < 0)
 186                         goto set_enable_error;
 187
 188                 sdata->enabled = false;
 189         }
 190
 191 set_enable_error:
 192         return err;
 193 }
 194 EXPORT_SYMBOL(st_sensors_set_enable);
 195
 196 int st_sensors_set_axis_enable(struct iio_dev *indio_dev, u8 axis_enable)
 197 {
 198         struct st_sensor_data *sdata = iio_priv(indio_dev);
 199
 200         return st_sensors_write_data_with_mask(indio_dev,
 201                                 sdata->sensor_settings->enable_axis.addr,
 202                                 sdata->sensor_settings->enable_axis.mask,
 203                                 axis_enable);
 204 }
 205 EXPORT_SYMBOL(st_sensors_set_axis_enable);
 206
 207 void st_sensors_power_enable(struct iio_dev *indio_dev)
 208 {
 209         struct st_sensor_data *pdata = iio_priv(indio_dev);
 210         int err;
 211
 212         /* Regulators not mandatory, but if requested we should enable them. */
 213         pdata->vdd = devm_regulator_get_optional(indio_dev->dev.parent, "vdd");
 214         if (!IS_ERR(pdata->vdd)) {
 215                 err = regulator_enable(pdata->vdd);
 216                 if (err != 0)
 217                         dev_warn(&indio_dev->dev,
 218                                  "Failed to enable specified Vdd supply\n");
 219         }
 220
 221         pdata->vdd_io = devm_regulator_get_optional(indio_dev->dev.parent, "vddio");
 222         if (!IS_ERR(pdata->vdd_io)) {
 223                 err = regulator_enable(pdata->vdd_io);
 224                 if (err != 0)
 225                         dev_warn(&indio_dev->dev,
 226                                  "Failed to enable specified Vdd_IO supply\n");
 227         }
 228 }
 229 EXPORT_SYMBOL(st_sensors_power_enable);
 230
 231 void st_sensors_power_disable(struct iio_dev *indio_dev)
 232 {
 233         struct st_sensor_data *pdata = iio_priv(indio_dev);
 234
 235         if (!IS_ERR(pdata->vdd))
 236                 regulator_disable(pdata->vdd);
 237
 238         if (!IS_ERR(pdata->vdd_io))
 239                 regulator_disable(pdata->vdd_io);
 240 }
 241 EXPORT_SYMBOL(st_sensors_power_disable);
 242
 243 static int st_sensors_set_drdy_int_pin(struct iio_dev *indio_dev,
 244                                         struct st_sensors_platform_data *pdata)
 245 {
 246         struct st_sensor_data *sdata = iio_priv(indio_dev);
 247
 248         switch (pdata->drdy_int_pin) {
 249         case 1:
 250                 if (sdata->sensor_settings->drdy_irq.mask_int1 == 0) {
 251                         dev_err(&indio_dev->dev,
 252                                         "DRDY on INT1 not available.\n");
 253                         return -EINVAL;
 254                 }
 255                 sdata->drdy_int_pin = 1;
 256                 break;
 257         case 2:
 258                 if (sdata->sensor_settings->drdy_irq.mask_int2 == 0) {
 259                         dev_err(&indio_dev->dev,
 260                                         "DRDY on INT2 not available.\n");
 261                         return -EINVAL;
 262                 }
 263                 sdata->drdy_int_pin = 2;
 264                 break;
 265         default:
 266                 dev_err(&indio_dev->dev, "DRDY on pdata not valid.\n");
 267                 return -EINVAL;
 268         }
 269
 270         return 0;
 271 }
 272
 273 #ifdef CONFIG_OF
 274 static struct st_sensors_platform_data *st_sensors_of_probe(struct device *dev,
 275                 struct st_sensors_platform_data *defdata)
 276 {
 277         struct st_sensors_platform_data *pdata;
 278         struct device_node *np = dev->of_node;
 279         u32 val;
 280
 281         if (!np)
 282                 return NULL;
 283
 284         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 285         if (!of_property_read_u32(np, "st,drdy-int-pin", &val) && (val <= 2))
 286                 pdata->drdy_int_pin = (u8) val;
 287         else
 288                 pdata->drdy_int_pin = defdata ? defdata->drdy_int_pin : 1;
 289
 290         return pdata;
 291 }
 292 #else
 293 static struct st_sensors_platform_data *st_sensors_of_probe(struct device *dev,
 294                 struct st_sensors_platform_data *defdata)
 295 {
 296         return NULL;
 297 }
 298 #endif
 299
 300 int st_sensors_init_sensor(struct iio_dev *indio_dev,
 301                                         struct st_sensors_platform_data *pdata)
 302 {
 303         struct st_sensor_data *sdata = iio_priv(indio_dev);
 304         struct st_sensors_platform_data *of_pdata;
 305         int err = 0;
 306
 307         /* If OF/DT pdata exists, it will take precedence of anything else */
 308         of_pdata = st_sensors_of_probe(indio_dev->dev.parent, pdata);
 309         if (of_pdata)
 310                 pdata = of_pdata;
 311
 312         if (pdata) {
 313                 err = st_sensors_set_drdy_int_pin(indio_dev, pdata);
 314                 if (err < 0)
 315                         return err;
 316         }
 317
 318         err = st_sensors_set_enable(indio_dev, false);
 319         if (err < 0)
 320                 return err;
 321
 322         if (sdata->current_fullscale) {
 323                 err = st_sensors_set_fullscale(indio_dev,
 324                                                 sdata->current_fullscale->num);
 325                 if (err < 0)
 326                         return err;
 327         } else
 328                 dev_info(&indio_dev->dev, "Full-scale not possible\n");
 329
 330         err = st_sensors_set_odr(indio_dev, sdata->odr);
 331         if (err < 0)
 332                 return err;
 333
 334         /* set BDU */
 335         err = st_sensors_write_data_with_mask(indio_dev,
 336                                         sdata->sensor_settings->bdu.addr,
 337                                         sdata->sensor_settings->bdu.mask, true);
 338         if (err < 0)
 339                 return err;
 340
 341         err = st_sensors_set_axis_enable(indio_dev, ST_SENSORS_ENABLE_ALL_AXIS);
 342
 343         return err;
 344 }
 345 EXPORT_SYMBOL(st_sensors_init_sensor);
 346
 347 int st_sensors_set_dataready_irq(struct iio_dev *indio_dev, bool enable)
 348 {
 349         int err;
 350         u8 drdy_mask;
 351         struct st_sensor_data *sdata = iio_priv(indio_dev);
 352
 353         if (!sdata->sensor_settings->drdy_irq.addr)
 354                 return 0;
 355
 356         /* Enable/Disable the interrupt generator 1. */
 357         if (sdata->sensor_settings->drdy_irq.ig1.en_addr > 0) {
 358                 err = st_sensors_write_data_with_mask(indio_dev,
 359                                 sdata->sensor_settings->drdy_irq.ig1.en_addr,
 360                                 sdata->sensor_settings->drdy_irq.ig1.en_mask,
 361                                 (int)enable);
 362                 if (err < 0)
 363                         goto st_accel_set_dataready_irq_error;
 364         }
 365
 366         if (sdata->drdy_int_pin == 1)
 367                 drdy_mask = sdata->sensor_settings->drdy_irq.mask_int1;
 368         else
 369                 drdy_mask = sdata->sensor_settings->drdy_irq.mask_int2;
 370
 371         /* Enable/Disable the interrupt generator for data ready. */
 372         err = st_sensors_write_data_with_mask(indio_dev,
 373                                         sdata->sensor_settings->drdy_irq.addr,
 374                                         drdy_mask, (int)enable);
 375
 376 st_accel_set_dataready_irq_error:
 377         return err;
 378 }
 379 EXPORT_SYMBOL(st_sensors_set_dataready_irq);
 380
 381 int st_sensors_set_fullscale_by_gain(struct iio_dev *indio_dev, int scale)
 382 {
 383         int err = -EINVAL, i;
 384         struct st_sensor_data *sdata = iio_priv(indio_dev);
 385
 386         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 387                 if ((sdata->sensor_settings->fs.fs_avl[i].gain == scale) &&
 388                                 (sdata->sensor_settings->fs.fs_avl[i].gain != 0)) {
 389                         err = 0;
 390                         break;
 391                 }
 392         }
 393         if (err < 0)
 394                 goto st_sensors_match_scale_error;
 395
 396         err = st_sensors_set_fullscale(indio_dev,
 397                                 sdata->sensor_settings->fs.fs_avl[i].num);
 398
 399 st_sensors_match_scale_error:
 400         return err;
 401 }
 402 EXPORT_SYMBOL(st_sensors_set_fullscale_by_gain);
 403
 404 static int st_sensors_read_axis_data(struct iio_dev *indio_dev,
 405                                 struct iio_chan_spec const *ch, int *data)
 406 {
 407         int err;
 408         u8 *outdata;
 409         struct st_sensor_data *sdata = iio_priv(indio_dev);
 410         unsigned int byte_for_channel = ch->scan_type.storagebits >> 3;
 411
 412         outdata = kmalloc(byte_for_channel, GFP_KERNEL);
 413         if (!outdata)
 414                 return -ENOMEM;
 415
 416         err = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
 417                                 ch->address, byte_for_channel,
 418                                 outdata, sdata->multiread_bit);
 419         if (err < 0)
 420                 goto st_sensors_free_memory;
 421
 422         if (byte_for_channel == 2)
 423                 *data = (s16)get_unaligned_le16(outdata);
 424         else if (byte_for_channel == 3)
 425                 *data = (s32)st_sensors_get_unaligned_le24(outdata);
 426
 427 st_sensors_free_memory:
 428         kfree(outdata);
 429
 430         return err;
 431 }
 432
 433 int st_sensors_read_info_raw(struct iio_dev *indio_dev,
 434                                 struct iio_chan_spec const *ch, int *val)
 435 {
 436         int err;
 437         struct st_sensor_data *sdata = iio_priv(indio_dev);
 438
 439         mutex_lock(&indio_dev->mlock);
 440         if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
 441                 err = -EBUSY;
 442                 goto out;
 443         } else {
 444                 err = st_sensors_set_enable(indio_dev, true);
 445                 if (err < 0)
 446                         goto out;
 447
 448                 msleep((sdata->sensor_settings->bootime * 1000) / sdata->odr);
 449                 err = st_sensors_read_axis_data(indio_dev, ch, val);
 450                 if (err < 0)
 451                         goto out;
 452
 453                 *val = *val >> ch->scan_type.shift;
 454
 455                 err = st_sensors_set_enable(indio_dev, false);
 456         }
 457 out:
 458         mutex_unlock(&indio_dev->mlock);
 459
 460         return err;
 461 }
 462 EXPORT_SYMBOL(st_sensors_read_info_raw);
 463
 464 int st_sensors_check_device_support(struct iio_dev *indio_dev,
 465                         int num_sensors_list,
 466                         const struct st_sensor_settings *sensor_settings)
 467 {
 468         u8 wai;
 469         int i, n, err;
 470         struct st_sensor_data *sdata = iio_priv(indio_dev);
 471
 472         err = sdata->tf->read_byte(&sdata->tb, sdata->dev,
 473                                         ST_SENSORS_DEFAULT_WAI_ADDRESS, &wai);
 474         if (err < 0) {
 475                 dev_err(&indio_dev->dev, "failed to read Who-Am-I register.\n");
 476                 goto read_wai_error;
 477         }
 478
 479         for (i = 0; i < num_sensors_list; i++) {
 480                 if (sensor_settings[i].wai == wai)
 481                         break;
 482         }
 483         if (i == num_sensors_list)
 484                 goto device_not_supported;
 485
 486         for (n = 0; n < ARRAY_SIZE(sensor_settings[i].sensors_supported); n++) {
 487                 if (strcmp(indio_dev->name,
 488                                 &sensor_settings[i].sensors_supported[n][0]) == 0)
 489                         break;
 490         }
 491         if (n == ARRAY_SIZE(sensor_settings[i].sensors_supported)) {
 492                 dev_err(&indio_dev->dev, "device name and WhoAmI mismatch.\n");
 493                 goto sensor_name_mismatch;
 494         }
 495
 496         sdata->sensor_settings =
 497                         (struct st_sensor_settings *)&sensor_settings[i];
 498
 499         return i;
 500
 501 device_not_supported:
 502         dev_err(&indio_dev->dev, "device not supported: WhoAmI (0x%x).\n", wai);
 503 sensor_name_mismatch:
 504         err = -ENODEV;
 505 read_wai_error:
 506         return err;
 507 }
 508 EXPORT_SYMBOL(st_sensors_check_device_support);
 509
 510 ssize_t st_sensors_sysfs_sampling_frequency_avail(struct device *dev,
 511                                 struct device_attribute *attr, char *buf)
 512 {
 513         int i, len = 0;
 514         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 515         struct st_sensor_data *sdata = iio_priv(indio_dev);
 516
 517         mutex_lock(&indio_dev->mlock);
 518         for (i = 0; i < ST_SENSORS_ODR_LIST_MAX; i++) {
 519                 if (sdata->sensor_settings->odr.odr_avl[i].hz == 0)
 520                         break;
 521
 522                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d ",
 523                                 sdata->sensor_settings->odr.odr_avl[i].hz);
 524         }
 525         mutex_unlock(&indio_dev->mlock);
 526         buf[len - 1] = '\n';
 527
 528         return len;
 529 }
 530 EXPORT_SYMBOL(st_sensors_sysfs_sampling_frequency_avail);
 531
 532 ssize_t st_sensors_sysfs_scale_avail(struct device *dev,
 533                                 struct device_attribute *attr, char *buf)
 534 {
 535         int i, len = 0;
 536         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 537         struct st_sensor_data *sdata = iio_priv(indio_dev);
 538
 539         mutex_lock(&indio_dev->mlock);
 540         for (i = 0; i < ST_SENSORS_FULLSCALE_AVL_MAX; i++) {
 541                 if (sdata->sensor_settings->fs.fs_avl[i].num == 0)
 542                         break;
 543
 544                 len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06u ",
 545                                 sdata->sensor_settings->fs.fs_avl[i].gain);
 546         }
 547         mutex_unlock(&indio_dev->mlock);
 548         buf[len - 1] = '\n';
 549
 550         return len;
 551 }
 552 EXPORT_SYMBOL(st_sensors_sysfs_scale_avail);
 553
 554 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 555 MODULE_DESCRIPTION("STMicroelectronics ST-sensors core");
 556 MODULE_LICENSE("GPL v2");