drivers/staging/iio/accel/adis16220_core.c

   1 /*
   2  * ADIS16220 Programmable Digital Vibration Sensor 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
  21 #include "../iio.h"
  22 #include "../sysfs.h"
  23 #include "accel.h"
  24 #include "../adc/adc.h"
  25
  26 #include "adis16220.h"
  27
  28 #define DRIVER_NAME             "adis16220"
  29
  30 /**
  31  * adis16220_spi_write_reg_8() - write single byte to a register
  32  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  33  * @reg_address: the address of the register to be written
  34  * @val: the value to write
  35  **/
  36 static int adis16220_spi_write_reg_8(struct device *dev,
  37                 u8 reg_address,
  38                 u8 val)
  39 {
  40         int ret;
  41         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  42         struct adis16220_state *st = iio_dev_get_devdata(indio_dev);
  43
  44         mutex_lock(&st->buf_lock);
  45         st->tx[0] = ADIS16220_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  * adis16220_spi_write_reg_16() - write 2 bytes to a pair of registers
  56  * @dev: device associated with child of actual device (iio_dev or iio_trig)
  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 adis16220_spi_write_reg_16(struct device *dev,
  62                 u8 lower_reg_address,
  63                 u16 value)
  64 {
  65         int ret;
  66         struct spi_message msg;
  67         struct iio_dev *indio_dev = dev_get_drvdata(dev);
  68         struct adis16220_state *st = iio_dev_get_devdata(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                         .cs_change = 1,
  81                         .delay_usecs = 35,
  82                 },
  83         };
  84
  85         mutex_lock(&st->buf_lock);
  86         st->tx[0] = ADIS16220_WRITE_REG(lower_reg_address);
  87         st->tx[1] = value & 0xFF;
  88         st->tx[2] = ADIS16220_WRITE_REG(lower_reg_address + 1);
  89         st->tx[3] = (value >> 8) & 0xFF;
  90
  91         spi_message_init(&msg);
  92         spi_message_add_tail(&xfers[0], &msg);
  93         spi_message_add_tail(&xfers[1], &msg);
  94         ret = spi_sync(st->us, &msg);
  95         mutex_unlock(&st->buf_lock);
  96
  97         return ret;
  98 }
  99
 100 /**
 101  * adis16220_spi_read_reg_16() - read 2 bytes from a 16-bit register
 102  * @dev: device associated with child of actual device (iio_dev or iio_trig)
 103  * @reg_address: the address of the lower of the two registers. Second register
 104  *               is assumed to have address one greater.
 105  * @val: somewhere to pass back the value read
 106  **/
 107 static int adis16220_spi_read_reg_16(struct device *dev,
 108                 u8 lower_reg_address,
 109                 u16 *val)
 110 {
 111         struct spi_message msg;
 112         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 113         struct adis16220_state *st = iio_dev_get_devdata(indio_dev);
 114         int ret;
 115         struct spi_transfer xfers[] = {
 116                 {
 117                         .tx_buf = st->tx,
 118                         .bits_per_word = 8,
 119                         .len = 2,
 120                         .cs_change = 1,
 121                         .delay_usecs = 35,
 122                 }, {
 123                         .rx_buf = st->rx,
 124                         .bits_per_word = 8,
 125                         .len = 2,
 126                         .cs_change = 1,
 127                         .delay_usecs = 35,
 128                 },
 129         };
 130
 131         mutex_lock(&st->buf_lock);
 132         st->tx[0] = ADIS16220_READ_REG(lower_reg_address);
 133         st->tx[1] = 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 adis16220_spi_read_signed(struct device *dev,
 153                 struct device_attribute *attr,
 154                 char *buf,
 155                 unsigned bits)
 156 {
 157         int ret;
 158         s16 val = 0;
 159         unsigned shift = 16 - bits;
 160         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 161
 162         ret = adis16220_spi_read_reg_16(dev, this_attr->address, (u16 *)&val);
 163         if (ret)
 164                 return ret;
 165
 166         val = ((s16)(val << shift) >> shift);
 167         return sprintf(buf, "%d\n", val);
 168 }
 169
 170 static ssize_t adis16220_read_12bit_unsigned(struct device *dev,
 171                 struct device_attribute *attr,
 172                 char *buf)
 173 {
 174         int ret;
 175         u16 val = 0;
 176         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 177
 178         ret = adis16220_spi_read_reg_16(dev, this_attr->address, &val);
 179         if (ret)
 180                 return ret;
 181
 182         return sprintf(buf, "%u\n", val & 0x0FFF);
 183 }
 184
 185 static ssize_t adis16220_read_16bit(struct device *dev,
 186                 struct device_attribute *attr,
 187                 char *buf)
 188 {
 189         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 190         ssize_t ret;
 191
 192         /* Take the iio_dev status lock */
 193         mutex_lock(&indio_dev->mlock);
 194         ret =  adis16220_spi_read_signed(dev, attr, buf, 16);
 195         mutex_unlock(&indio_dev->mlock);
 196
 197         return ret;
 198 }
 199
 200 static ssize_t adis16220_write_16bit(struct device *dev,
 201                 struct device_attribute *attr,
 202                 const char *buf,
 203                 size_t len)
 204 {
 205         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 206         int ret;
 207         long val;
 208
 209         ret = strict_strtol(buf, 10, &val);
 210         if (ret)
 211                 goto error_ret;
 212         ret = adis16220_spi_write_reg_16(dev, this_attr->address, val);
 213
 214 error_ret:
 215         return ret ? ret : len;
 216 }
 217
 218 static int adis16220_capture(struct device *dev)
 219 {
 220         int ret;
 221         ret = adis16220_spi_write_reg_16(dev,
 222                         ADIS16220_GLOB_CMD,
 223                         0xBF08); /* initiates a manual data capture */
 224         if (ret)
 225                 dev_err(dev, "problem beginning capture");
 226
 227         msleep(10); /* delay for capture to finish */
 228
 229         return ret;
 230 }
 231
 232 static int adis16220_reset(struct device *dev)
 233 {
 234         int ret;
 235         ret = adis16220_spi_write_reg_8(dev,
 236                         ADIS16220_GLOB_CMD,
 237                         ADIS16220_GLOB_CMD_SW_RESET);
 238         if (ret)
 239                 dev_err(dev, "problem resetting device");
 240
 241         return ret;
 242 }
 243
 244 static ssize_t adis16220_write_reset(struct device *dev,
 245                 struct device_attribute *attr,
 246                 const char *buf, size_t len)
 247 {
 248         if (len < 1)
 249                 return -1;
 250         switch (buf[0]) {
 251         case '1':
 252         case 'y':
 253         case 'Y':
 254                 return adis16220_reset(dev) == 0 ? len : -EIO;
 255         }
 256         return -1;
 257 }
 258
 259 static ssize_t adis16220_write_capture(struct device *dev,
 260                 struct device_attribute *attr,
 261                 const char *buf, size_t len)
 262 {
 263         if (len < 1)
 264                 return -1;
 265         switch (buf[0]) {
 266         case '1':
 267         case 'y':
 268         case 'Y':
 269                 return adis16220_capture(dev) == 0 ? len : -EIO;
 270         }
 271         return -1;
 272 }
 273
 274 static int adis16220_check_status(struct device *dev)
 275 {
 276         u16 status;
 277         int ret;
 278
 279         ret = adis16220_spi_read_reg_16(dev, ADIS16220_DIAG_STAT, &status);
 280
 281         if (ret < 0) {
 282                 dev_err(dev, "Reading status failed\n");
 283                 goto error_ret;
 284         }
 285         ret = status & 0x7F;
 286
 287         if (status & ADIS16220_DIAG_STAT_VIOLATION)
 288                 dev_err(dev, "Capture period violation/interruption\n");
 289         if (status & ADIS16220_DIAG_STAT_SPI_FAIL)
 290                 dev_err(dev, "SPI failure\n");
 291         if (status & ADIS16220_DIAG_STAT_FLASH_UPT)
 292                 dev_err(dev, "Flash update failed\n");
 293         if (status & ADIS16220_DIAG_STAT_POWER_HIGH)
 294                 dev_err(dev, "Power supply above 3.625V\n");
 295         if (status & ADIS16220_DIAG_STAT_POWER_LOW)
 296                 dev_err(dev, "Power supply below 3.15V\n");
 297
 298 error_ret:
 299         return ret;
 300 }
 301
 302 static int adis16220_self_test(struct device *dev)
 303 {
 304         int ret;
 305         ret = adis16220_spi_write_reg_16(dev,
 306                         ADIS16220_MSC_CTRL,
 307                         ADIS16220_MSC_CTRL_SELF_TEST_EN);
 308         if (ret) {
 309                 dev_err(dev, "problem starting self test");
 310                 goto err_ret;
 311         }
 312
 313         adis16220_check_status(dev);
 314
 315 err_ret:
 316         return ret;
 317 }
 318
 319 static int adis16220_initial_setup(struct adis16220_state *st)
 320 {
 321         int ret;
 322         struct device *dev = &st->indio_dev->dev;
 323
 324         /* Do self test */
 325         ret = adis16220_self_test(dev);
 326         if (ret) {
 327                 dev_err(dev, "self test failure");
 328                 goto err_ret;
 329         }
 330
 331         /* Read status register to check the result */
 332         ret = adis16220_check_status(dev);
 333         if (ret) {
 334                 adis16220_reset(dev);
 335                 dev_err(dev, "device not playing ball -> reset");
 336                 msleep(ADIS16220_STARTUP_DELAY);
 337                 ret = adis16220_check_status(dev);
 338                 if (ret) {
 339                         dev_err(dev, "giving up");
 340                         goto err_ret;
 341                 }
 342         }
 343
 344         printk(KERN_INFO DRIVER_NAME ": at CS%d (irq %d)\n",
 345                         st->us->chip_select, st->us->irq);
 346
 347 err_ret:
 348         return ret;
 349 }
 350
 351 static ssize_t adis16220_capture_buffer_read(struct adis16220_state *st,
 352                                         char *buf,
 353                                         loff_t off,
 354                                         size_t count,
 355                                         int addr)
 356 {
 357         struct spi_message msg;
 358         struct spi_transfer xfers[] = {
 359                 {
 360                         .tx_buf = st->tx,
 361                         .bits_per_word = 8,
 362                         .len = 2,
 363                         .cs_change = 1,
 364                         .delay_usecs = 25,
 365                 }, {
 366                         .tx_buf = st->tx,
 367                         .rx_buf = st->rx,
 368                         .bits_per_word = 8,
 369                         .cs_change = 1,
 370                         .delay_usecs = 25,
 371                 },
 372         };
 373         int ret;
 374         int i;
 375
 376         if (unlikely(!count))
 377                 return count;
 378
 379         if ((off >= ADIS16220_CAPTURE_SIZE) || (count & 1) || (off & 1))
 380                 return -EINVAL;
 381
 382         if (off + count > ADIS16220_CAPTURE_SIZE)
 383                 count = ADIS16220_CAPTURE_SIZE - off;
 384
 385         /* write the begin position of capture buffer */
 386         ret = adis16220_spi_write_reg_16(&st->indio_dev->dev,
 387                                         ADIS16220_CAPT_PNTR,
 388                                         off > 1);
 389         if (ret)
 390                 return -EIO;
 391
 392         /* read count/2 values from capture buffer */
 393         mutex_lock(&st->buf_lock);
 394
 395         for (i = 0; i < count; i += 2) {
 396                 st->tx[i] = ADIS16220_READ_REG(addr);
 397                 st->tx[i + 1] = 0;
 398         }
 399         xfers[1].len = count;
 400
 401         spi_message_init(&msg);
 402         spi_message_add_tail(&xfers[0], &msg);
 403         spi_message_add_tail(&xfers[1], &msg);
 404         ret = spi_sync(st->us, &msg);
 405         if (ret) {
 406
 407                 mutex_unlock(&st->buf_lock);
 408                 return -EIO;
 409         }
 410
 411         memcpy(buf, st->rx, count);
 412
 413         mutex_unlock(&st->buf_lock);
 414         return count;
 415 }
 416
 417 static ssize_t adis16220_accel_bin_read(struct file *filp, struct kobject *kobj,
 418                                         struct bin_attribute *attr,
 419                                         char *buf,
 420                                         loff_t off,
 421                                         size_t count)
 422 {
 423         struct device *dev = container_of(kobj, struct device, kobj);
 424         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 425         struct adis16220_state *st = iio_dev_get_devdata(indio_dev);
 426
 427         return adis16220_capture_buffer_read(st, buf,
 428                                         off, count,
 429                                         ADIS16220_CAPT_BUFA);
 430 }
 431
 432 static struct bin_attribute accel_bin = {
 433         .attr = {
 434                 .name = "accel_bin",
 435                 .mode = S_IRUGO,
 436         },
 437         .read = adis16220_accel_bin_read,
 438         .size = ADIS16220_CAPTURE_SIZE,
 439 };
 440
 441 static ssize_t adis16220_adc1_bin_read(struct file *filp, struct kobject *kobj,
 442                                 struct bin_attribute *attr,
 443                                 char *buf, loff_t off,
 444                                 size_t count)
 445 {
 446         struct device *dev = container_of(kobj, struct device, kobj);
 447         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 448         struct adis16220_state *st = iio_dev_get_devdata(indio_dev);
 449
 450         return adis16220_capture_buffer_read(st, buf,
 451                                         off, count,
 452                                         ADIS16220_CAPT_BUF1);
 453 }
 454
 455 static struct bin_attribute adc1_bin = {
 456         .attr = {
 457                 .name = "in0_bin",
 458                 .mode = S_IRUGO,
 459         },
 460         .read =  adis16220_adc1_bin_read,
 461         .size = ADIS16220_CAPTURE_SIZE,
 462 };
 463
 464 static ssize_t adis16220_adc2_bin_read(struct file *filp, struct kobject *kobj,
 465                                 struct bin_attribute *attr,
 466                                 char *buf, loff_t off,
 467                                 size_t count)
 468 {
 469         struct device *dev = container_of(kobj, struct device, kobj);
 470         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 471         struct adis16220_state *st = iio_dev_get_devdata(indio_dev);
 472
 473         return adis16220_capture_buffer_read(st, buf,
 474                                         off, count,
 475                                         ADIS16220_CAPT_BUF2);
 476 }
 477
 478
 479 static struct bin_attribute adc2_bin = {
 480         .attr = {
 481                 .name = "in1_bin",
 482                 .mode = S_IRUGO,
 483         },
 484         .read =  adis16220_adc2_bin_read,
 485         .size = ADIS16220_CAPTURE_SIZE,
 486 };
 487
 488 static IIO_DEV_ATTR_IN_NAMED_RAW(0, supply, adis16220_read_12bit_unsigned,
 489                 ADIS16220_CAPT_SUPPLY);
 490 static IIO_CONST_ATTR_IN_NAMED_SCALE(0, supply, "0.0012207");
 491 static IIO_DEV_ATTR_ACCEL(adis16220_read_16bit, ADIS16220_CAPT_BUFA);
 492 static IIO_DEVICE_ATTR(accel_peak_raw, S_IRUGO, adis16220_read_16bit,
 493                 NULL, ADIS16220_CAPT_PEAKA);
 494 static IIO_DEV_ATTR_ACCEL_OFFSET(S_IWUSR | S_IRUGO,
 495                 adis16220_read_16bit,
 496                 adis16220_write_16bit,
 497                 ADIS16220_ACCL_NULL);
 498 static IIO_CONST_ATTR_ACCEL_SCALE("0.18704223545");
 499 static IIO_DEV_ATTR_TEMP_RAW(adis16220_read_12bit_unsigned);
 500 static IIO_CONST_ATTR_TEMP_OFFSET("25");
 501 static IIO_CONST_ATTR_TEMP_SCALE("-0.47");
 502
 503 static IIO_DEV_ATTR_IN_RAW(1, adis16220_read_16bit, ADIS16220_CAPT_BUF1);
 504 static IIO_DEV_ATTR_IN_RAW(2, adis16220_read_16bit, ADIS16220_CAPT_BUF2);
 505
 506 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL,
 507                 adis16220_write_reset, 0);
 508
 509 #define IIO_DEV_ATTR_CAPTURE(_store)                            \
 510         IIO_DEVICE_ATTR(capture, S_IWUSR, NULL, _store, 0)
 511
 512 static IIO_DEV_ATTR_CAPTURE(adis16220_write_capture);
 513
 514 #define IIO_DEV_ATTR_CAPTURE_COUNT(_mode, _show, _store, _addr)         \
 515         IIO_DEVICE_ATTR(capture_count, _mode, _show, _store, _addr)
 516
 517 static IIO_DEV_ATTR_CAPTURE_COUNT(S_IWUSR | S_IRUGO,
 518                 adis16220_read_16bit,
 519                 adis16220_write_16bit,
 520                 ADIS16220_CAPT_PNTR);
 521
 522 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100200");
 523
 524 static struct attribute *adis16220_attributes[] = {
 525         &iio_dev_attr_in0_supply_raw.dev_attr.attr,
 526         &iio_const_attr_in0_supply_scale.dev_attr.attr,
 527         &iio_dev_attr_accel_raw.dev_attr.attr,
 528         &iio_dev_attr_accel_offset.dev_attr.attr,
 529         &iio_dev_attr_accel_peak_raw.dev_attr.attr,
 530         &iio_const_attr_accel_scale.dev_attr.attr,
 531         &iio_dev_attr_temp_raw.dev_attr.attr,
 532         &iio_dev_attr_in1_raw.dev_attr.attr,
 533         &iio_dev_attr_in2_raw.dev_attr.attr,
 534         &iio_const_attr_temp_offset.dev_attr.attr,
 535         &iio_const_attr_temp_scale.dev_attr.attr,
 536         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 537         &iio_dev_attr_reset.dev_attr.attr,
 538         &iio_dev_attr_capture.dev_attr.attr,
 539         &iio_dev_attr_capture_count.dev_attr.attr,
 540         NULL
 541 };
 542
 543 static const struct attribute_group adis16220_attribute_group = {
 544         .attrs = adis16220_attributes,
 545 };
 546
 547 static const struct iio_info adis16220_info = {
 548         .attrs = &adis16220_attribute_group,
 549         .driver_module = THIS_MODULE,
 550 };
 551 static int __devinit adis16220_probe(struct spi_device *spi)
 552 {
 553         int ret, regdone = 0;
 554         struct adis16220_state *st = kzalloc(sizeof *st, GFP_KERNEL);
 555         if (!st) {
 556                 ret =  -ENOMEM;
 557                 goto error_ret;
 558         }
 559         /* this is only used for removal purposes */
 560         spi_set_drvdata(spi, st);
 561
 562         /* Allocate the comms buffers */
 563         st->rx = kzalloc(sizeof(*st->rx)*ADIS16220_MAX_RX, GFP_KERNEL);
 564         if (st->rx == NULL) {
 565                 ret = -ENOMEM;
 566                 goto error_free_st;
 567         }
 568         st->tx = kzalloc(sizeof(*st->tx)*ADIS16220_MAX_TX, GFP_KERNEL);
 569         if (st->tx == NULL) {
 570                 ret = -ENOMEM;
 571                 goto error_free_rx;
 572         }
 573         st->us = spi;
 574         mutex_init(&st->buf_lock);
 575         /* setup the industrialio driver allocated elements */
 576         st->indio_dev = iio_allocate_device(0);
 577         if (st->indio_dev == NULL) {
 578                 ret = -ENOMEM;
 579                 goto error_free_tx;
 580         }
 581
 582         st->indio_dev->name = spi->dev.driver->name;
 583         st->indio_dev->dev.parent = &spi->dev;
 584         st->indio_dev->info = &adis16220_info;
 585         st->indio_dev->dev_data = (void *)(st);
 586         st->indio_dev->modes = INDIO_DIRECT_MODE;
 587
 588         ret = iio_device_register(st->indio_dev);
 589         if (ret)
 590                 goto error_free_dev;
 591         regdone = 1;
 592
 593         ret = sysfs_create_bin_file(&st->indio_dev->dev.kobj, &accel_bin);
 594         if (ret)
 595                 goto error_free_dev;
 596
 597         ret = sysfs_create_bin_file(&st->indio_dev->dev.kobj, &adc1_bin);
 598         if (ret)
 599                 goto error_rm_accel_bin;
 600
 601         ret = sysfs_create_bin_file(&st->indio_dev->dev.kobj, &adc2_bin);
 602         if (ret)
 603                 goto error_rm_adc1_bin;
 604
 605         /* Get the device into a sane initial state */
 606         ret = adis16220_initial_setup(st);
 607         if (ret)
 608                 goto error_rm_adc2_bin;
 609         return 0;
 610
 611 error_rm_adc2_bin:
 612         sysfs_remove_bin_file(&st->indio_dev->dev.kobj, &adc2_bin);
 613 error_rm_adc1_bin:
 614         sysfs_remove_bin_file(&st->indio_dev->dev.kobj, &adc1_bin);
 615 error_rm_accel_bin:
 616         sysfs_remove_bin_file(&st->indio_dev->dev.kobj, &accel_bin);
 617 error_free_dev:
 618         if (regdone)
 619                 iio_device_unregister(st->indio_dev);
 620         else
 621                 iio_free_device(st->indio_dev);
 622 error_free_tx:
 623         kfree(st->tx);
 624 error_free_rx:
 625         kfree(st->rx);
 626 error_free_st:
 627         kfree(st);
 628 error_ret:
 629         return ret;
 630 }
 631
 632 static int adis16220_remove(struct spi_device *spi)
 633 {
 634         struct adis16220_state *st = spi_get_drvdata(spi);
 635         struct iio_dev *indio_dev = st->indio_dev;
 636
 637         flush_scheduled_work();
 638
 639         sysfs_remove_bin_file(&st->indio_dev->dev.kobj, &adc2_bin);
 640         sysfs_remove_bin_file(&st->indio_dev->dev.kobj, &adc1_bin);
 641         sysfs_remove_bin_file(&st->indio_dev->dev.kobj, &accel_bin);
 642         iio_device_unregister(indio_dev);
 643         kfree(st->tx);
 644         kfree(st->rx);
 645         kfree(st);
 646
 647         return 0;
 648 }
 649
 650 static struct spi_driver adis16220_driver = {
 651         .driver = {
 652                 .name = "adis16220",
 653                 .owner = THIS_MODULE,
 654         },
 655         .probe = adis16220_probe,
 656         .remove = __devexit_p(adis16220_remove),
 657 };
 658
 659 static __init int adis16220_init(void)
 660 {
 661         return spi_register_driver(&adis16220_driver);
 662 }
 663 module_init(adis16220_init);
 664
 665 static __exit void adis16220_exit(void)
 666 {
 667         spi_unregister_driver(&adis16220_driver);
 668 }
 669 module_exit(adis16220_exit);
 670
 671 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 672 MODULE_DESCRIPTION("Analog Devices ADIS16220 Digital Vibration Sensor");
 673 MODULE_LICENSE("GPL v2");