drivers/staging/iio/accel/adis16240_core.c

   1 /*
   2  * ADIS16240 Programmable Impact Sensor and Recorder driver
   3  *
   4  * Copyright 2010 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2 or later.
   7  */
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/irq.h>
  11 #include <linux/gpio.h>
  12 #include <linux/delay.h>
  13 #include <linux/mutex.h>
  14 #include <linux/device.h>
  15 #include <linux/kernel.h>
  16 #include <linux/spi/spi.h>
  17 #include <linux/slab.h>
  18 #include <linux/sysfs.h>
  19 #include <linux/list.h>
  20 #include <linux/module.h>
  21
  22 #include "../iio.h"
  23 #include "../sysfs.h"
  24 #include "../ring_generic.h"
  25
  26 #include "adis16240.h"
  27
  28 #define DRIVER_NAME             "adis16240"
  29
  30 static int adis16240_check_status(struct iio_dev *indio_dev);
  31
  32 /**
  33  * adis16240_spi_write_reg_8() - write single byte to a register
  34  * @indio_dev: iio_dev associated with device
  35  * @reg_address: the address of the register to be written
  36  * @val: the value to write
  37  **/
  38 static int adis16240_spi_write_reg_8(struct iio_dev *indio_dev,
  39                                      u8 reg_address,
  40                                      u8 val)
  41 {
  42         int ret;
  43         struct adis16240_state *st = iio_priv(indio_dev);
  44
  45         mutex_lock(&st->buf_lock);
  46         st->tx[0] = ADIS16240_WRITE_REG(reg_address);
  47         st->tx[1] = val;
  48
  49         ret = spi_write(st->us, st->tx, 2);
  50         mutex_unlock(&st->buf_lock);
  51
  52         return ret;
  53 }
  54
  55 /**
  56  * adis16240_spi_write_reg_16() - write 2 bytes to a pair of registers
  57  * @indio_dev: iio_dev for this device
  58  * @reg_address: the address of the lower of the two registers. Second register
  59  *               is assumed to have address one greater.
  60  * @val: value to be written
  61  **/
  62 static int adis16240_spi_write_reg_16(struct iio_dev *indio_dev,
  63                                       u8 lower_reg_address,
  64                                       u16 value)
  65 {
  66         int ret;
  67         struct spi_message msg;
  68         struct adis16240_state *st = iio_priv(indio_dev);
  69         struct spi_transfer xfers[] = {
  70                 {
  71                         .tx_buf = st->tx,
  72                         .bits_per_word = 8,
  73                         .len = 2,
  74                         .cs_change = 1,
  75                         .delay_usecs = 35,
  76                 }, {
  77                         .tx_buf = st->tx + 2,
  78                         .bits_per_word = 8,
  79                         .len = 2,
  80                         .delay_usecs = 35,
  81                 },
  82         };
  83
  84         mutex_lock(&st->buf_lock);
  85         st->tx[0] = ADIS16240_WRITE_REG(lower_reg_address);
  86         st->tx[1] = value & 0xFF;
  87         st->tx[2] = ADIS16240_WRITE_REG(lower_reg_address + 1);
  88         st->tx[3] = (value >> 8) & 0xFF;
  89
  90         spi_message_init(&msg);
  91         spi_message_add_tail(&xfers[0], &msg);
  92         spi_message_add_tail(&xfers[1], &msg);
  93         ret = spi_sync(st->us, &msg);
  94         mutex_unlock(&st->buf_lock);
  95
  96         return ret;
  97 }
  98
  99 /**
 100  * adis16240_spi_read_reg_16() - read 2 bytes from a 16-bit register
 101  * @indio_dev: iio_dev for this device
 102  * @reg_address: the address of the lower of the two registers. Second register
 103  *               is assumed to have address one greater.
 104  * @val: somewhere to pass back the value read
 105  **/
 106 static int adis16240_spi_read_reg_16(struct iio_dev *indio_dev,
 107                 u8 lower_reg_address,
 108                 u16 *val)
 109 {
 110         struct spi_message msg;
 111         struct adis16240_state *st = iio_priv(indio_dev);
 112         int ret;
 113         struct spi_transfer xfers[] = {
 114                 {
 115                         .tx_buf = st->tx,
 116                         .bits_per_word = 8,
 117                         .len = 2,
 118                         .cs_change = 1,
 119                         .delay_usecs = 35,
 120                 }, {
 121                         .rx_buf = st->rx,
 122                         .bits_per_word = 8,
 123                         .len = 2,
 124                         .cs_change = 1,
 125                         .delay_usecs = 35,
 126                 },
 127         };
 128
 129         mutex_lock(&st->buf_lock);
 130         st->tx[0] = ADIS16240_READ_REG(lower_reg_address);
 131         st->tx[1] = 0;
 132         st->tx[2] = 0;
 133         st->tx[3] = 0;
 134
 135         spi_message_init(&msg);
 136         spi_message_add_tail(&xfers[0], &msg);
 137         spi_message_add_tail(&xfers[1], &msg);
 138         ret = spi_sync(st->us, &msg);
 139         if (ret) {
 140                 dev_err(&st->us->dev,
 141                         "problem when reading 16 bit register 0x%02X",
 142                         lower_reg_address);
 143                 goto error_ret;
 144         }
 145         *val = (st->rx[0] << 8) | st->rx[1];
 146
 147 error_ret:
 148         mutex_unlock(&st->buf_lock);
 149         return ret;
 150 }
 151
 152 static ssize_t adis16240_spi_read_signed(struct device *dev,
 153                 struct device_attribute *attr,
 154                 char *buf,
 155                 unsigned bits)
 156 {
 157         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 158         int ret;
 159         s16 val = 0;
 160         unsigned shift = 16 - bits;
 161         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 162
 163         ret = adis16240_spi_read_reg_16(indio_dev,
 164                                         this_attr->address, (u16 *)&val);
 165         if (ret)
 166                 return ret;
 167
 168         if (val & ADIS16240_ERROR_ACTIVE)
 169                 adis16240_check_status(indio_dev);
 170
 171         val = ((s16)(val << shift) >> shift);
 172         return sprintf(buf, "%d\n", val);
 173 }
 174
 175 static ssize_t adis16240_read_12bit_signed(struct device *dev,
 176                 struct device_attribute *attr,
 177                 char *buf)
 178 {
 179         ssize_t ret;
 180         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 181
 182         /* Take the iio_dev status lock */
 183         mutex_lock(&indio_dev->mlock);
 184         ret =  adis16240_spi_read_signed(dev, attr, buf, 12);
 185         mutex_unlock(&indio_dev->mlock);
 186
 187         return ret;
 188 }
 189
 190 static int adis16240_reset(struct iio_dev *indio_dev)
 191 {
 192         int ret;
 193         ret = adis16240_spi_write_reg_8(indio_dev,
 194                         ADIS16240_GLOB_CMD,
 195                         ADIS16240_GLOB_CMD_SW_RESET);
 196         if (ret)
 197                 dev_err(&indio_dev->dev, "problem resetting device");
 198
 199         return ret;
 200 }
 201
 202 static ssize_t adis16240_write_reset(struct device *dev,
 203                 struct device_attribute *attr,
 204                 const char *buf, size_t len)
 205 {
 206         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 207
 208         if (len < 1)
 209                 return -EINVAL;
 210         switch (buf[0]) {
 211         case '1':
 212         case 'y':
 213         case 'Y':
 214                 return adis16240_reset(indio_dev);
 215         }
 216         return -EINVAL;
 217 }
 218
 219 int adis16240_set_irq(struct iio_dev *indio_dev, bool enable)
 220 {
 221         int ret = 0;
 222         u16 msc;
 223
 224         ret = adis16240_spi_read_reg_16(indio_dev,
 225                                         ADIS16240_MSC_CTRL, &msc);
 226         if (ret)
 227                 goto error_ret;
 228
 229         msc |= ADIS16240_MSC_CTRL_ACTIVE_HIGH;
 230         msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_DIO2;
 231         if (enable)
 232                 msc |= ADIS16240_MSC_CTRL_DATA_RDY_EN;
 233         else
 234                 msc &= ~ADIS16240_MSC_CTRL_DATA_RDY_EN;
 235
 236         ret = adis16240_spi_write_reg_16(indio_dev,
 237                                          ADIS16240_MSC_CTRL, msc);
 238
 239 error_ret:
 240         return ret;
 241 }
 242
 243 static int adis16240_self_test(struct iio_dev *indio_dev)
 244 {
 245         int ret;
 246         ret = adis16240_spi_write_reg_16(indio_dev,
 247                         ADIS16240_MSC_CTRL,
 248                         ADIS16240_MSC_CTRL_SELF_TEST_EN);
 249         if (ret) {
 250                 dev_err(&indio_dev->dev, "problem starting self test");
 251                 goto err_ret;
 252         }
 253
 254         msleep(ADIS16240_STARTUP_DELAY);
 255
 256         adis16240_check_status(indio_dev);
 257
 258 err_ret:
 259         return ret;
 260 }
 261
 262 static int adis16240_check_status(struct iio_dev *indio_dev)
 263 {
 264         u16 status;
 265         int ret;
 266         struct device *dev = &indio_dev->dev;
 267
 268         ret = adis16240_spi_read_reg_16(indio_dev,
 269                                         ADIS16240_DIAG_STAT, &status);
 270
 271         if (ret < 0) {
 272                 dev_err(dev, "Reading status failed\n");
 273                 goto error_ret;
 274         }
 275
 276         ret = status & 0x2F;
 277         if (status & ADIS16240_DIAG_STAT_PWRON_FAIL)
 278                 dev_err(dev, "Power-on, self-test fail\n");
 279         if (status & ADIS16240_DIAG_STAT_SPI_FAIL)
 280                 dev_err(dev, "SPI failure\n");
 281         if (status & ADIS16240_DIAG_STAT_FLASH_UPT)
 282                 dev_err(dev, "Flash update failed\n");
 283         if (status & ADIS16240_DIAG_STAT_POWER_HIGH)
 284                 dev_err(dev, "Power supply above 3.625V\n");
 285         if (status & ADIS16240_DIAG_STAT_POWER_LOW)
 286                 dev_err(dev, "Power supply below 2.225V\n");
 287
 288 error_ret:
 289         return ret;
 290 }
 291
 292 static int adis16240_initial_setup(struct iio_dev *indio_dev)
 293 {
 294         int ret;
 295         struct device *dev = &indio_dev->dev;
 296
 297         /* Disable IRQ */
 298         ret = adis16240_set_irq(indio_dev, false);
 299         if (ret) {
 300                 dev_err(dev, "disable irq failed");
 301                 goto err_ret;
 302         }
 303
 304         /* Do self test */
 305         ret = adis16240_self_test(indio_dev);
 306         if (ret) {
 307                 dev_err(dev, "self test failure");
 308                 goto err_ret;
 309         }
 310
 311         /* Read status register to check the result */
 312         ret = adis16240_check_status(indio_dev);
 313         if (ret) {
 314                 adis16240_reset(indio_dev);
 315                 dev_err(dev, "device not playing ball -> reset");
 316                 msleep(ADIS16240_STARTUP_DELAY);
 317                 ret = adis16240_check_status(indio_dev);
 318                 if (ret) {
 319                         dev_err(dev, "giving up");
 320                         goto err_ret;
 321                 }
 322         }
 323
 324 err_ret:
 325         return ret;
 326 }
 327
 328 static IIO_DEVICE_ATTR(accel_xyz_squared_peak_raw, S_IRUGO,
 329                        adis16240_read_12bit_signed, NULL,
 330                        ADIS16240_XYZPEAK_OUT);
 331
 332 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16240_write_reset, 0);
 333
 334 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("4096");
 335
 336 enum adis16240_chan {
 337         in_supply,
 338         in_aux,
 339         accel_x,
 340         accel_y,
 341         accel_z,
 342         temp,
 343 };
 344
 345 static const u8 adis16240_addresses[6][3] = {
 346         [in_supply] = { ADIS16240_SUPPLY_OUT },
 347         [in_aux] = { ADIS16240_AUX_ADC },
 348         [accel_x] = { ADIS16240_XACCL_OUT, ADIS16240_XACCL_OFF,
 349                       ADIS16240_XPEAK_OUT },
 350         [accel_y] = { ADIS16240_YACCL_OUT, ADIS16240_YACCL_OFF,
 351                       ADIS16240_YPEAK_OUT },
 352         [accel_z] = { ADIS16240_ZACCL_OUT, ADIS16240_ZACCL_OFF,
 353                       ADIS16240_ZPEAK_OUT },
 354         [temp] = { ADIS16240_TEMP_OUT },
 355 };
 356
 357 static int adis16240_read_raw(struct iio_dev *indio_dev,
 358                               struct iio_chan_spec const *chan,
 359                               int *val, int *val2,
 360                               long mask)
 361 {
 362         int ret;
 363         int bits;
 364         u8 addr;
 365         s16 val16;
 366
 367         switch (mask) {
 368         case 0:
 369                 mutex_lock(&indio_dev->mlock);
 370                 addr = adis16240_addresses[chan->address][0];
 371                 ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
 372                 if (ret) {
 373                         mutex_unlock(&indio_dev->mlock);
 374                         return ret;
 375                 }
 376
 377                 if (val16 & ADIS16240_ERROR_ACTIVE) {
 378                         ret = adis16240_check_status(indio_dev);
 379                         if (ret) {
 380                                 mutex_unlock(&indio_dev->mlock);
 381                                 return ret;
 382                         }
 383                 }
 384                 val16 = val16 & ((1 << chan->scan_type.realbits) - 1);
 385                 if (chan->scan_type.sign == 's')
 386                         val16 = (s16)(val16 <<
 387                                       (16 - chan->scan_type.realbits)) >>
 388                                 (16 - chan->scan_type.realbits);
 389                 *val = val16;
 390                 mutex_unlock(&indio_dev->mlock);
 391                 return IIO_VAL_INT;
 392         case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
 393         case (1 << IIO_CHAN_INFO_SCALE_SHARED):
 394                 switch (chan->type) {
 395                 case IIO_IN:
 396                         *val = 0;
 397                         if (chan->channel == 0)
 398                                 *val2 = 4880;
 399                         else
 400                                 return -EINVAL;
 401                         return IIO_VAL_INT_PLUS_MICRO;
 402                 case IIO_TEMP:
 403                         *val = 0;
 404                         *val2 = 244000;
 405                         return IIO_VAL_INT_PLUS_MICRO;
 406                 case IIO_ACCEL:
 407                         *val = 0;
 408                         *val2 = 504062;
 409                         return IIO_VAL_INT_PLUS_MICRO;
 410                 default:
 411                         return -EINVAL;
 412                 }
 413                 break;
 414         case (1 << IIO_CHAN_INFO_PEAK_SCALE_SHARED):
 415                 *val = 6;
 416                 *val2 = 629295;
 417                 return IIO_VAL_INT_PLUS_MICRO;
 418         case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
 419                 *val = 25;
 420                 return IIO_VAL_INT;
 421         case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
 422                 bits = 10;
 423                 mutex_lock(&indio_dev->mlock);
 424                 addr = adis16240_addresses[chan->address][1];
 425                 ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
 426                 if (ret) {
 427                         mutex_unlock(&indio_dev->mlock);
 428                         return ret;
 429                 }
 430                 val16 &= (1 << bits) - 1;
 431                 val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
 432                 *val = val16;
 433                 mutex_unlock(&indio_dev->mlock);
 434                 return IIO_VAL_INT;
 435         case (1 << IIO_CHAN_INFO_PEAK_SEPARATE):
 436                 bits = 10;
 437                 mutex_lock(&indio_dev->mlock);
 438                 addr = adis16240_addresses[chan->address][2];
 439                 ret = adis16240_spi_read_reg_16(indio_dev, addr, &val16);
 440                 if (ret) {
 441                         mutex_unlock(&indio_dev->mlock);
 442                         return ret;
 443                 }
 444                 val16 &= (1 << bits) - 1;
 445                 val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
 446                 *val = val16;
 447                 mutex_unlock(&indio_dev->mlock);
 448                 return IIO_VAL_INT;
 449         }
 450         return -EINVAL;
 451 }
 452
 453 static int adis16240_write_raw(struct iio_dev *indio_dev,
 454                                struct iio_chan_spec const *chan,
 455                                int val,
 456                                int val2,
 457                                long mask)
 458 {
 459         int bits = 10;
 460         s16 val16;
 461         u8 addr;
 462         switch (mask) {
 463         case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
 464                 val16 = val & ((1 << bits) - 1);
 465                 addr = adis16240_addresses[chan->address][1];
 466                 return adis16240_spi_write_reg_16(indio_dev, addr, val16);
 467         }
 468         return -EINVAL;
 469 }
 470
 471 static struct iio_chan_spec adis16240_channels[] = {
 472         IIO_CHAN(IIO_IN, 0, 1, 0, "supply", 0, 0,
 473                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
 474                  in_supply, ADIS16240_SCAN_SUPPLY,
 475                  IIO_ST('u', 10, 16, 0), 0),
 476         IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 1, 0,
 477                  0,
 478                  in_aux, ADIS16240_SCAN_AUX_ADC,
 479                  IIO_ST('u', 10, 16, 0), 0),
 480         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_X,
 481                  (1 << IIO_CHAN_INFO_SCALE_SHARED) |
 482                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 483                  accel_x, ADIS16240_SCAN_ACC_X,
 484                  IIO_ST('s', 10, 16, 0), 0),
 485         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Y,
 486                  (1 << IIO_CHAN_INFO_SCALE_SHARED) |
 487                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 488                  accel_y, ADIS16240_SCAN_ACC_Y,
 489                  IIO_ST('s', 10, 16, 0), 0),
 490         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Z,
 491                  (1 << IIO_CHAN_INFO_SCALE_SHARED) |
 492                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 493                  accel_z, ADIS16240_SCAN_ACC_Z,
 494                  IIO_ST('s', 10, 16, 0), 0),
 495         IIO_CHAN(IIO_TEMP, 0, 1, 0, NULL, 0, 0,
 496                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
 497                  temp, ADIS16240_SCAN_TEMP,
 498                  IIO_ST('u', 10, 16, 0), 0),
 499         IIO_CHAN_SOFT_TIMESTAMP(6)
 500 };
 501
 502 static struct attribute *adis16240_attributes[] = {
 503         &iio_dev_attr_accel_xyz_squared_peak_raw.dev_attr.attr,
 504         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 505         &iio_dev_attr_reset.dev_attr.attr,
 506         NULL
 507 };
 508
 509 static const struct attribute_group adis16240_attribute_group = {
 510         .attrs = adis16240_attributes,
 511 };
 512
 513 static const struct iio_info adis16240_info = {
 514         .attrs = &adis16240_attribute_group,
 515         .read_raw = &adis16240_read_raw,
 516         .write_raw = &adis16240_write_raw,
 517         .driver_module = THIS_MODULE,
 518 };
 519
 520 static int __devinit adis16240_probe(struct spi_device *spi)
 521 {
 522         int ret, regdone = 0;
 523         struct adis16240_state *st;
 524         struct iio_dev *indio_dev;
 525
 526         /* setup the industrialio driver allocated elements */
 527         indio_dev = iio_allocate_device(sizeof(*st));
 528         if (indio_dev == NULL) {
 529                 ret = -ENOMEM;
 530                 goto error_ret;
 531         }
 532         st = iio_priv(indio_dev);
 533         /* this is only used for removal purposes */
 534         spi_set_drvdata(spi, indio_dev);
 535
 536         st->us = spi;
 537         mutex_init(&st->buf_lock);
 538
 539         indio_dev->name = spi->dev.driver->name;
 540         indio_dev->dev.parent = &spi->dev;
 541         indio_dev->info = &adis16240_info;
 542         indio_dev->channels = adis16240_channels;
 543         indio_dev->num_channels = ARRAY_SIZE(adis16240_channels);
 544         indio_dev->modes = INDIO_DIRECT_MODE;
 545
 546         ret = adis16240_configure_ring(indio_dev);
 547         if (ret)
 548                 goto error_free_dev;
 549
 550         ret = iio_device_register(indio_dev);
 551         if (ret)
 552                 goto error_unreg_ring_funcs;
 553         regdone = 1;
 554
 555         ret = iio_ring_buffer_register_ex(indio_dev->ring, 0,
 556                                           adis16240_channels,
 557                                           ARRAY_SIZE(adis16240_channels));
 558         if (ret) {
 559                 printk(KERN_ERR "failed to initialize the ring\n");
 560                 goto error_unreg_ring_funcs;
 561         }
 562
 563         if (spi->irq) {
 564                 ret = adis16240_probe_trigger(indio_dev);
 565                 if (ret)
 566                         goto error_uninitialize_ring;
 567         }
 568
 569         /* Get the device into a sane initial state */
 570         ret = adis16240_initial_setup(indio_dev);
 571         if (ret)
 572                 goto error_remove_trigger;
 573         return 0;
 574
 575 error_remove_trigger:
 576         adis16240_remove_trigger(indio_dev);
 577 error_uninitialize_ring:
 578         iio_ring_buffer_unregister(indio_dev->ring);
 579 error_unreg_ring_funcs:
 580         adis16240_unconfigure_ring(indio_dev);
 581 error_free_dev:
 582         if (regdone)
 583                 iio_device_unregister(indio_dev);
 584         else
 585                 iio_free_device(indio_dev);
 586 error_ret:
 587         return ret;
 588 }
 589
 590 static int adis16240_remove(struct spi_device *spi)
 591 {
 592
 593         struct iio_dev *indio_dev = spi_get_drvdata(spi);
 594
 595         flush_scheduled_work();
 596
 597         adis16240_remove_trigger(indio_dev);
 598         iio_ring_buffer_unregister(indio_dev->ring);
 599         iio_device_unregister(indio_dev);
 600         adis16240_unconfigure_ring(indio_dev);
 601
 602         return 0;
 603 }
 604
 605 static struct spi_driver adis16240_driver = {
 606         .driver = {
 607                 .name = "adis16240",
 608                 .owner = THIS_MODULE,
 609         },
 610         .probe = adis16240_probe,
 611         .remove = __devexit_p(adis16240_remove),
 612 };
 613
 614 static __init int adis16240_init(void)
 615 {
 616         return spi_register_driver(&adis16240_driver);
 617 }
 618 module_init(adis16240_init);
 619
 620 static __exit void adis16240_exit(void)
 621 {
 622         spi_unregister_driver(&adis16240_driver);
 623 }
 624 module_exit(adis16240_exit);
 625
 626 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 627 MODULE_DESCRIPTION("Analog Devices Programmable Impact Sensor and Recorder");
 628 MODULE_LICENSE("GPL v2");