drivers/staging/iio/accel/adis16204_core.c

   1 /*
   2  * ADIS16204 Programmable High-g Digital Impact Sensor and Recorder
   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
  21 #include "../iio.h"
  22 #include "../sysfs.h"
  23 #include "../ring_generic.h"
  24 #include "accel.h"
  25 #include "../adc/adc.h"
  26
  27 #include "adis16204.h"
  28
  29 #define DRIVER_NAME             "adis16204"
  30
  31 /**
  32  * adis16204_spi_write_reg_8() - write single byte to a register
  33  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  34  * @reg_address: the address of the register to be written
  35  * @val: the value to write
  36  **/
  37 static int adis16204_spi_write_reg_8(struct iio_dev *indio_dev,
  38                 u8 reg_address,
  39                 u8 val)
  40 {
  41         int ret;
  42         struct adis16204_state *st = iio_priv(indio_dev);
  43
  44         mutex_lock(&st->buf_lock);
  45         st->tx[0] = ADIS16204_WRITE_REG(reg_address);
  46         st->tx[1] = val;
  47
  48         ret = spi_write(st->us, st->tx, 2);
  49         mutex_unlock(&st->buf_lock);
  50
  51         return ret;
  52 }
  53
  54 /**
  55  * adis16204_spi_write_reg_16() - write 2 bytes to a pair of registers
  56  * @indio_dev: iio device associated with child of actual device
  57  * @reg_address: the address of the lower of the two registers. Second register
  58  *               is assumed to have address one greater.
  59  * @val: value to be written
  60  **/
  61 static int adis16204_spi_write_reg_16(struct iio_dev *indio_dev,
  62                 u8 lower_reg_address,
  63                 u16 value)
  64 {
  65         int ret;
  66         struct spi_message msg;
  67         struct adis16204_state *st = iio_priv(indio_dev);
  68         struct spi_transfer xfers[] = {
  69                 {
  70                         .tx_buf = st->tx,
  71                         .bits_per_word = 8,
  72                         .len = 2,
  73                         .cs_change = 1,
  74                 }, {
  75                         .tx_buf = st->tx + 2,
  76                         .bits_per_word = 8,
  77                         .len = 2,
  78                         .cs_change = 1,
  79                 },
  80         };
  81
  82         mutex_lock(&st->buf_lock);
  83         st->tx[0] = ADIS16204_WRITE_REG(lower_reg_address);
  84         st->tx[1] = value & 0xFF;
  85         st->tx[2] = ADIS16204_WRITE_REG(lower_reg_address + 1);
  86         st->tx[3] = (value >> 8) & 0xFF;
  87
  88         spi_message_init(&msg);
  89         spi_message_add_tail(&xfers[0], &msg);
  90         spi_message_add_tail(&xfers[1], &msg);
  91         ret = spi_sync(st->us, &msg);
  92         mutex_unlock(&st->buf_lock);
  93
  94         return ret;
  95 }
  96
  97 /**
  98  * adis16204_spi_read_reg_16() - read 2 bytes from a 16-bit register
  99  * @indio_dev: iio device associated with child of actual device
 100  * @reg_address: the address of the lower of the two registers. Second register
 101  *               is assumed to have address one greater.
 102  * @val: somewhere to pass back the value read
 103  **/
 104 static int adis16204_spi_read_reg_16(struct iio_dev *indio_dev,
 105                                      u8 lower_reg_address,
 106                                      u16 *val)
 107 {
 108         struct spi_message msg;
 109         struct adis16204_state *st = iio_priv(indio_dev);
 110         int ret;
 111         struct spi_transfer xfers[] = {
 112                 {
 113                         .tx_buf = st->tx,
 114                         .bits_per_word = 8,
 115                         .len = 2,
 116                         .cs_change = 1,
 117                         .delay_usecs = 20,
 118                 }, {
 119                         .rx_buf = st->rx,
 120                         .bits_per_word = 8,
 121                         .len = 2,
 122                         .delay_usecs = 20,
 123                 },
 124         };
 125
 126         mutex_lock(&st->buf_lock);
 127         st->tx[0] = ADIS16204_READ_REG(lower_reg_address);
 128         st->tx[1] = 0;
 129
 130         spi_message_init(&msg);
 131         spi_message_add_tail(&xfers[0], &msg);
 132         spi_message_add_tail(&xfers[1], &msg);
 133         ret = spi_sync(st->us, &msg);
 134         if (ret) {
 135                 dev_err(&st->us->dev, "problem when reading 16 bit register 0x%02X",
 136                                 lower_reg_address);
 137                 goto error_ret;
 138         }
 139         *val = (st->rx[0] << 8) | st->rx[1];
 140
 141 error_ret:
 142         mutex_unlock(&st->buf_lock);
 143         return ret;
 144 }
 145
 146 static int adis16204_check_status(struct iio_dev *indio_dev)
 147 {
 148         u16 status;
 149         int ret;
 150
 151         ret = adis16204_spi_read_reg_16(indio_dev,
 152                                         ADIS16204_DIAG_STAT, &status);
 153         if (ret < 0) {
 154                 dev_err(&indio_dev->dev, "Reading status failed\n");
 155                 goto error_ret;
 156         }
 157         ret = status & 0x1F;
 158
 159         if (status & ADIS16204_DIAG_STAT_SELFTEST_FAIL)
 160                 dev_err(&indio_dev->dev, "Self test failure\n");
 161         if (status & ADIS16204_DIAG_STAT_SPI_FAIL)
 162                 dev_err(&indio_dev->dev, "SPI failure\n");
 163         if (status & ADIS16204_DIAG_STAT_FLASH_UPT)
 164                 dev_err(&indio_dev->dev, "Flash update failed\n");
 165         if (status & ADIS16204_DIAG_STAT_POWER_HIGH)
 166                 dev_err(&indio_dev->dev, "Power supply above 3.625V\n");
 167         if (status & ADIS16204_DIAG_STAT_POWER_LOW)
 168                 dev_err(&indio_dev->dev, "Power supply below 2.975V\n");
 169
 170 error_ret:
 171         return ret;
 172 }
 173
 174 static ssize_t adis16204_read_14bit_signed(struct device *dev,
 175                 struct device_attribute *attr,
 176                 char *buf)
 177 {
 178         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 179         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 180         s16 val = 0;
 181         ssize_t ret;
 182
 183         mutex_lock(&indio_dev->mlock);
 184
 185         ret = adis16204_spi_read_reg_16(indio_dev,
 186                                         this_attr->address, (u16 *)&val);
 187         if (!ret) {
 188                 if (val & ADIS16204_ERROR_ACTIVE)
 189                         adis16204_check_status(indio_dev);
 190
 191                 val = ((s16)(val << 2) >> 2);
 192                 ret = sprintf(buf, "%d\n", val);
 193         }
 194
 195         mutex_unlock(&indio_dev->mlock);
 196
 197         return ret;
 198 }
 199
 200 static int adis16204_reset(struct iio_dev *indio_dev)
 201 {
 202         int ret;
 203         ret = adis16204_spi_write_reg_8(indio_dev,
 204                         ADIS16204_GLOB_CMD,
 205                         ADIS16204_GLOB_CMD_SW_RESET);
 206         if (ret)
 207                 dev_err(&indio_dev->dev, "problem resetting device");
 208
 209         return ret;
 210 }
 211
 212 static ssize_t adis16204_write_reset(struct device *dev,
 213                 struct device_attribute *attr,
 214                 const char *buf, size_t len)
 215 {
 216         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 217
 218         if (len < 1)
 219                 return -EINVAL;
 220         switch (buf[0]) {
 221         case '1':
 222         case 'y':
 223         case 'Y':
 224                 return adis16204_reset(indio_dev);
 225         }
 226         return -EINVAL;
 227 }
 228
 229 int adis16204_set_irq(struct iio_dev *indio_dev, bool enable)
 230 {
 231         int ret = 0;
 232         u16 msc;
 233
 234         ret = adis16204_spi_read_reg_16(indio_dev, ADIS16204_MSC_CTRL, &msc);
 235         if (ret)
 236                 goto error_ret;
 237
 238         msc |= ADIS16204_MSC_CTRL_ACTIVE_HIGH;
 239         msc &= ~ADIS16204_MSC_CTRL_DATA_RDY_DIO2;
 240         if (enable)
 241                 msc |= ADIS16204_MSC_CTRL_DATA_RDY_EN;
 242         else
 243                 msc &= ~ADIS16204_MSC_CTRL_DATA_RDY_EN;
 244
 245         ret = adis16204_spi_write_reg_16(indio_dev, ADIS16204_MSC_CTRL, msc);
 246
 247 error_ret:
 248         return ret;
 249 }
 250
 251 static int adis16204_self_test(struct iio_dev *indio_dev)
 252 {
 253         int ret;
 254         ret = adis16204_spi_write_reg_16(indio_dev,
 255                         ADIS16204_MSC_CTRL,
 256                         ADIS16204_MSC_CTRL_SELF_TEST_EN);
 257         if (ret) {
 258                 dev_err(&indio_dev->dev, "problem starting self test");
 259                 goto err_ret;
 260         }
 261
 262         adis16204_check_status(indio_dev);
 263
 264 err_ret:
 265         return ret;
 266 }
 267
 268 static int adis16204_initial_setup(struct iio_dev *indio_dev)
 269 {
 270         int ret;
 271
 272         /* Disable IRQ */
 273         ret = adis16204_set_irq(indio_dev, false);
 274         if (ret) {
 275                 dev_err(&indio_dev->dev, "disable irq failed");
 276                 goto err_ret;
 277         }
 278
 279         /* Do self test */
 280         ret = adis16204_self_test(indio_dev);
 281         if (ret) {
 282                 dev_err(&indio_dev->dev, "self test failure");
 283                 goto err_ret;
 284         }
 285
 286         /* Read status register to check the result */
 287         ret = adis16204_check_status(indio_dev);
 288         if (ret) {
 289                 adis16204_reset(indio_dev);
 290                 dev_err(&indio_dev->dev, "device not playing ball -> reset");
 291                 msleep(ADIS16204_STARTUP_DELAY);
 292                 ret = adis16204_check_status(indio_dev);
 293                 if (ret) {
 294                         dev_err(&indio_dev->dev, "giving up");
 295                         goto err_ret;
 296                 }
 297         }
 298
 299 err_ret:
 300         return ret;
 301 }
 302 static IIO_DEV_ATTR_ACCEL_XY(adis16204_read_14bit_signed,
 303                 ADIS16204_XY_RSS_OUT);
 304 static IIO_DEV_ATTR_ACCEL_XPEAK(adis16204_read_14bit_signed,
 305                 ADIS16204_X_PEAK_OUT);
 306 static IIO_DEV_ATTR_ACCEL_YPEAK(adis16204_read_14bit_signed,
 307                 ADIS16204_Y_PEAK_OUT);
 308 static IIO_DEV_ATTR_ACCEL_XYPEAK(adis16204_read_14bit_signed,
 309                 ADIS16204_XY_PEAK_OUT);
 310 static IIO_CONST_ATTR(accel_xy_scale, "0.017125");
 311
 312 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, adis16204_write_reset, 0);
 313
 314 enum adis16204_channel {
 315         in_supply,
 316         in_aux,
 317         temp,
 318         accel_x,
 319         accel_y,
 320 };
 321
 322 static u8 adis16204_addresses[5][2] = {
 323         [in_supply] = { ADIS16204_SUPPLY_OUT },
 324         [in_aux] = { ADIS16204_AUX_ADC },
 325         [temp] = { ADIS16204_TEMP_OUT },
 326         [accel_x] = { ADIS16204_XACCL_OUT, ADIS16204_XACCL_NULL },
 327         [accel_y] = { ADIS16204_XACCL_OUT, ADIS16204_YACCL_NULL },
 328 };
 329 static int adis16204_read_raw(struct iio_dev *indio_dev,
 330                               struct iio_chan_spec const *chan,
 331                               int *val, int *val2,
 332                               long mask)
 333 {
 334         int ret;
 335         int bits;
 336         u8 addr;
 337         s16 val16;
 338
 339         switch (mask) {
 340         case 0:
 341                 mutex_lock(&indio_dev->mlock);
 342                 addr = adis16204_addresses[chan->address][0];
 343                 ret = adis16204_spi_read_reg_16(indio_dev, addr, &val16);
 344                 if (ret) {
 345                         mutex_unlock(&indio_dev->mlock);
 346                         return ret;
 347                 }
 348
 349                 if (val16 & ADIS16204_ERROR_ACTIVE) {
 350                         ret = adis16204_check_status(indio_dev);
 351                         if (ret) {
 352                                 mutex_unlock(&indio_dev->mlock);
 353                                 return ret;
 354                         }
 355                 }
 356                 val16 = val16 & ((1 << chan->scan_type.realbits) - 1);
 357                 if (chan->scan_type.sign == 's')
 358                         val16 = (s16)(val16 <<
 359                                       (16 - chan->scan_type.realbits)) >>
 360                                 (16 - chan->scan_type.realbits);
 361                 *val = val16;
 362                 mutex_unlock(&indio_dev->mlock);
 363                 return IIO_VAL_INT;
 364         case (1 << IIO_CHAN_INFO_SCALE_SEPARATE):
 365                 switch (chan->type) {
 366                 case IIO_IN:
 367                         *val = 0;
 368                         if (chan->channel == 0)
 369                                 *val2 = 1220;
 370                         else
 371                                 *val2 = 610;
 372                         return IIO_VAL_INT_PLUS_MICRO;
 373                 case IIO_TEMP:
 374                         *val = 0;
 375                         *val2 = -470000;
 376                         return IIO_VAL_INT_PLUS_MICRO;
 377                 case IIO_ACCEL:
 378                         *val = 0;
 379                         if (chan->channel == 'x')
 380                                 *val2 = 17125;
 381                         else
 382                                 *val2 = 8407;
 383                         return IIO_VAL_INT_PLUS_MICRO;
 384                 default:
 385                         return -EINVAL;
 386                 }
 387                 break;
 388         case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
 389                 *val = 25;
 390                 return IIO_VAL_INT;
 391         case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
 392                 switch (chan->type) {
 393                 case IIO_ACCEL:
 394                         bits = 12;
 395                         break;
 396                 default:
 397                         return -EINVAL;
 398                 };
 399                 mutex_lock(&indio_dev->mlock);
 400                 addr = adis16204_addresses[chan->address][1];
 401                 ret = adis16204_spi_read_reg_16(indio_dev, addr, &val16);
 402                 if (ret) {
 403                         mutex_unlock(&indio_dev->mlock);
 404                         return ret;
 405                 }
 406                 val16 &= (1 << bits) - 1;
 407                 val16 = (s16)(val16 << (16 - bits)) >> (16 - bits);
 408                 *val = val16;
 409                 mutex_unlock(&indio_dev->mlock);
 410                 return IIO_VAL_INT;
 411         }
 412         return -EINVAL;
 413 }
 414
 415 static int adis16204_write_raw(struct iio_dev *indio_dev,
 416                                struct iio_chan_spec const *chan,
 417                                int val,
 418                                int val2,
 419                                long mask)
 420 {
 421         int bits;
 422         s16 val16;
 423         u8 addr;
 424         switch (mask) {
 425         case (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE):
 426                 switch (chan->type) {
 427                 case IIO_ACCEL:
 428                         bits = 12;
 429                         break;
 430                 default:
 431                         return -EINVAL;
 432                 };
 433                 val16 = val & ((1 << bits) - 1);
 434                 addr = adis16204_addresses[chan->address][1];
 435                 return adis16204_spi_write_reg_16(indio_dev, addr, val16);
 436         }
 437         return -EINVAL;
 438 }
 439
 440 static struct iio_chan_spec adis16204_channels[] = {
 441         IIO_CHAN(IIO_IN, 0, 0, 0, "supply", 0, 0,
 442                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
 443                  in_supply, ADIS16204_SCAN_SUPPLY,
 444                  IIO_ST('u', 12, 16, 0), 0),
 445         IIO_CHAN(IIO_IN, 0, 1, 0, NULL, 1, 0,
 446                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE),
 447                  in_aux, ADIS16204_SCAN_AUX_ADC,
 448                  IIO_ST('u', 12, 16, 0), 0),
 449         IIO_CHAN(IIO_TEMP, 0, 1, 0, NULL, 0, 0,
 450                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE) |
 451                  (1 << IIO_CHAN_INFO_OFFSET_SEPARATE),
 452                  temp, ADIS16204_SCAN_TEMP,
 453                  IIO_ST('u', 12, 16, 0), 0),
 454         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_X,
 455                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE) |
 456                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 457                  accel_x, ADIS16204_SCAN_ACC_X,
 458                  IIO_ST('s', 14, 16, 0), 0),
 459         IIO_CHAN(IIO_ACCEL, 1, 0, 0, NULL, 0, IIO_MOD_Y,
 460                  (1 << IIO_CHAN_INFO_SCALE_SEPARATE) |
 461                  (1 << IIO_CHAN_INFO_CALIBBIAS_SEPARATE),
 462                  accel_y, ADIS16204_SCAN_ACC_Y,
 463                  IIO_ST('s', 14, 16, 0), 0),
 464         IIO_CHAN_SOFT_TIMESTAMP(5),
 465 };
 466 static struct attribute *adis16204_attributes[] = {
 467         &iio_dev_attr_reset.dev_attr.attr,
 468         &iio_dev_attr_accel_xy.dev_attr.attr,
 469         &iio_dev_attr_accel_xpeak.dev_attr.attr,
 470         &iio_dev_attr_accel_ypeak.dev_attr.attr,
 471         &iio_dev_attr_accel_xypeak.dev_attr.attr,
 472         &iio_const_attr_accel_xy_scale.dev_attr.attr,
 473         NULL
 474 };
 475
 476 static const struct attribute_group adis16204_attribute_group = {
 477         .attrs = adis16204_attributes,
 478 };
 479
 480 static const struct iio_info adis16204_info = {
 481         .attrs = &adis16204_attribute_group,
 482         .read_raw = &adis16204_read_raw,
 483         .write_raw = &adis16204_write_raw,
 484         .driver_module = THIS_MODULE,
 485 };
 486
 487 static int __devinit adis16204_probe(struct spi_device *spi)
 488 {
 489         int ret, regdone = 0;
 490         struct adis16204_state *st;
 491         struct iio_dev *indio_dev;
 492
 493         /* setup the industrialio driver allocated elements */
 494         indio_dev = iio_allocate_device(sizeof(*st));
 495         if (indio_dev == NULL) {
 496                 ret = -ENOMEM;
 497                 goto error_ret;
 498         }
 499         st = iio_priv(indio_dev);
 500         /* this is only used for removal purposes */
 501         spi_set_drvdata(spi, indio_dev);
 502         st->us = spi;
 503         mutex_init(&st->buf_lock);
 504
 505         indio_dev->name = spi->dev.driver->name;
 506         indio_dev->dev.parent = &spi->dev;
 507         indio_dev->info = &adis16204_info;
 508         indio_dev->channels = adis16204_channels;
 509         indio_dev->num_channels = ARRAY_SIZE(adis16204_channels);
 510         indio_dev->modes = INDIO_DIRECT_MODE;
 511
 512         ret = adis16204_configure_ring(indio_dev);
 513         if (ret)
 514                 goto error_free_dev;
 515
 516         ret = iio_device_register(indio_dev);
 517         if (ret)
 518                 goto error_unreg_ring_funcs;
 519         regdone = 1;
 520
 521         ret = iio_ring_buffer_register_ex(indio_dev->ring, 0,
 522                                           adis16204_channels,
 523                                           ARRAY_SIZE(adis16204_channels));
 524         if (ret) {
 525                 printk(KERN_ERR "failed to initialize the ring\n");
 526                 goto error_unreg_ring_funcs;
 527         }
 528
 529         if (spi->irq) {
 530                 ret = adis16204_probe_trigger(indio_dev);
 531                 if (ret)
 532                         goto error_uninitialize_ring;
 533         }
 534
 535         /* Get the device into a sane initial state */
 536         ret = adis16204_initial_setup(indio_dev);
 537         if (ret)
 538                 goto error_remove_trigger;
 539         return 0;
 540
 541 error_remove_trigger:
 542         adis16204_remove_trigger(indio_dev);
 543 error_uninitialize_ring:
 544         iio_ring_buffer_unregister(indio_dev->ring);
 545 error_unreg_ring_funcs:
 546         adis16204_unconfigure_ring(indio_dev);
 547 error_free_dev:
 548         if (regdone)
 549                 iio_device_unregister(indio_dev);
 550         else
 551                 iio_free_device(indio_dev);
 552 error_ret:
 553         return ret;
 554 }
 555
 556 static int adis16204_remove(struct spi_device *spi)
 557 {
 558         struct iio_dev *indio_dev = spi_get_drvdata(spi);
 559
 560         adis16204_remove_trigger(indio_dev);
 561         iio_ring_buffer_unregister(indio_dev->ring);
 562         iio_device_unregister(indio_dev);
 563         adis16204_unconfigure_ring(indio_dev);
 564
 565         return 0;
 566 }
 567
 568 static struct spi_driver adis16204_driver = {
 569         .driver = {
 570                 .name = "adis16204",
 571                 .owner = THIS_MODULE,
 572         },
 573         .probe = adis16204_probe,
 574         .remove = __devexit_p(adis16204_remove),
 575 };
 576
 577 static __init int adis16204_init(void)
 578 {
 579         return spi_register_driver(&adis16204_driver);
 580 }
 581 module_init(adis16204_init);
 582
 583 static __exit void adis16204_exit(void)
 584 {
 585         spi_unregister_driver(&adis16204_driver);
 586 }
 587 module_exit(adis16204_exit);
 588
 589 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 590 MODULE_DESCRIPTION("ADIS16204 High-g Digital Impact Sensor and Recorder");
 591 MODULE_LICENSE("GPL v2");