drivers/staging/iio/adc/ad7745.c

   1 /*
   2  * AD774X capacitive sensor driver supporting AD7745/6/7
   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/gpio.h>
  11 #include <linux/device.h>
  12 #include <linux/kernel.h>
  13 #include <linux/slab.h>
  14 #include <linux/sysfs.h>
  15 #include <linux/list.h>
  16 #include <linux/i2c.h>
  17
  18 #include "../iio.h"
  19 #include "../sysfs.h"
  20
  21 /*
  22  * AD774X registers definition
  23  */
  24
  25 #define AD774X_STATUS           0
  26 #define AD774X_STATUS_RDY       (1 << 2)
  27 #define AD774X_STATUS_RDYVT     (1 << 1)
  28 #define AD774X_STATUS_RDYCAP    (1 << 0)
  29 #define AD774X_CAP_DATA_HIGH    1
  30 #define AD774X_CAP_DATA_MID     2
  31 #define AD774X_CAP_DATA_LOW     3
  32 #define AD774X_VT_DATA_HIGH     4
  33 #define AD774X_VT_DATA_MID      5
  34 #define AD774X_VT_DATA_LOW      6
  35 #define AD774X_CAP_SETUP        7
  36 #define AD774X_VT_SETUP         8
  37 #define AD774X_EXEC_SETUP       9
  38 #define AD774X_CFG              10
  39 #define AD774X_CAPDACA          11
  40 #define AD774X_CAPDACB          12
  41 #define AD774X_CAPDAC_EN        (1 << 7)
  42 #define AD774X_CAP_OFFH         13
  43 #define AD774X_CAP_OFFL         14
  44 #define AD774X_CAP_GAINH        15
  45 #define AD774X_CAP_GAINL        16
  46 #define AD774X_VOLT_GAINH       17
  47 #define AD774X_VOLT_GAINL       18
  48
  49 #define AD774X_MAX_CONV_MODE    6
  50
  51 /*
  52  * struct ad774x_chip_info - chip specifc information
  53  */
  54
  55 struct ad774x_chip_info {
  56         struct i2c_client *client;
  57         bool inter;
  58         u16 cap_offs;                   /* Capacitive offset */
  59         u16 cap_gain;                   /* Capacitive gain calibration */
  60         u16 volt_gain;                  /* Voltage gain calibration */
  61         u8  cap_setup;
  62         u8  vt_setup;
  63         u8  exec_setup;
  64
  65         char *conversion_mode;
  66 };
  67
  68 struct ad774x_conversion_mode {
  69         char *name;
  70         u8 reg_cfg;
  71 };
  72
  73 static struct ad774x_conversion_mode
  74 ad774x_conv_mode_table[AD774X_MAX_CONV_MODE] = {
  75         { "idle", 0 },
  76         { "continuous-conversion", 1 },
  77         { "single-conversion", 2 },
  78         { "power-down", 3 },
  79         { "offset-calibration", 5 },
  80         { "gain-calibration", 6 },
  81 };
  82
  83 /*
  84  * ad774x register access by I2C
  85  */
  86
  87 static int ad774x_i2c_read(struct ad774x_chip_info *chip, u8 reg, u8 *data, int len)
  88 {
  89         struct i2c_client *client = chip->client;
  90         int ret;
  91
  92         ret = i2c_master_send(client, &reg, 1);
  93         if (ret < 0) {
  94                 dev_err(&client->dev, "I2C write error\n");
  95                 return ret;
  96         }
  97
  98         ret = i2c_master_recv(client, data, len);
  99         if (ret < 0) {
 100                 dev_err(&client->dev, "I2C read error\n");
 101                 return ret;
 102         }
 103
 104         return ret;
 105 }
 106
 107 static int ad774x_i2c_write(struct ad774x_chip_info *chip, u8 reg, u8 data)
 108 {
 109         struct i2c_client *client = chip->client;
 110         int ret;
 111
 112         u8 tx[2] = {
 113                 reg,
 114                 data,
 115         };
 116
 117         ret = i2c_master_send(client, tx, 2);
 118         if (ret < 0)
 119                 dev_err(&client->dev, "I2C write error\n");
 120
 121         return ret;
 122 }
 123
 124 /*
 125  * sysfs nodes
 126  */
 127
 128 #define IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(_show)                              \
 129         IIO_DEVICE_ATTR(available_conversion_modes, S_IRUGO, _show, NULL, 0)
 130 #define IIO_DEV_ATTR_CONVERSION_MODE(_mode, _show, _store)              \
 131         IIO_DEVICE_ATTR(conversion_mode, _mode, _show, _store, 0)
 132 #define IIO_DEV_ATTR_CAP_SETUP(_mode, _show, _store)            \
 133         IIO_DEVICE_ATTR(cap_setup, _mode, _show, _store, 0)
 134 #define IIO_DEV_ATTR_VT_SETUP(_mode, _show, _store)              \
 135         IIO_DEVICE_ATTR(in0_setup, _mode, _show, _store, 0)
 136 #define IIO_DEV_ATTR_EXEC_SETUP(_mode, _show, _store)              \
 137         IIO_DEVICE_ATTR(exec_setup, _mode, _show, _store, 0)
 138 #define IIO_DEV_ATTR_VOLT_GAIN(_mode, _show, _store)            \
 139         IIO_DEVICE_ATTR(in0_gain, _mode, _show, _store, 0)
 140 #define IIO_DEV_ATTR_CAP_OFFS(_mode, _show, _store)             \
 141         IIO_DEVICE_ATTR(cap_offs, _mode, _show, _store, 0)
 142 #define IIO_DEV_ATTR_CAP_GAIN(_mode, _show, _store)             \
 143         IIO_DEVICE_ATTR(cap_gain, _mode, _show, _store, 0)
 144 #define IIO_DEV_ATTR_CAP_DATA(_show)            \
 145         IIO_DEVICE_ATTR(cap0_raw, S_IRUGO, _show, NULL, 0)
 146 #define IIO_DEV_ATTR_VT_DATA(_show)             \
 147         IIO_DEVICE_ATTR(in0_raw, S_IRUGO, _show, NULL, 0)
 148
 149 static ssize_t ad774x_show_conversion_modes(struct device *dev,
 150                 struct device_attribute *attr,
 151                 char *buf)
 152 {
 153         int i;
 154         int len = 0;
 155
 156         for (i = 0; i < AD774X_MAX_CONV_MODE; i++)
 157                 len += sprintf(buf + len, "%s ", ad774x_conv_mode_table[i].name);
 158
 159         len += sprintf(buf + len, "\n");
 160
 161         return len;
 162 }
 163
 164 static IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(ad774x_show_conversion_modes);
 165
 166 static ssize_t ad774x_show_conversion_mode(struct device *dev,
 167                 struct device_attribute *attr,
 168                 char *buf)
 169 {
 170         struct iio_dev *dev_info = dev_get_drvdata(dev);
 171         struct ad774x_chip_info *chip = iio_priv(dev_info);
 172
 173         return sprintf(buf, "%s\n", chip->conversion_mode);
 174 }
 175
 176 static ssize_t ad774x_store_conversion_mode(struct device *dev,
 177                 struct device_attribute *attr,
 178                 const char *buf,
 179                 size_t len)
 180 {
 181         struct iio_dev *dev_info = dev_get_drvdata(dev);
 182         struct ad774x_chip_info *chip = iio_priv(dev_info);
 183         u8 cfg;
 184         int i;
 185
 186         ad774x_i2c_read(chip, AD774X_CFG, &cfg, 1);
 187
 188         for (i = 0; i < AD774X_MAX_CONV_MODE; i++) {
 189                 if (strncmp(buf, ad774x_conv_mode_table[i].name,
 190                                 strlen(ad774x_conv_mode_table[i].name) - 1) == 0) {
 191                         chip->conversion_mode = ad774x_conv_mode_table[i].name;
 192                         cfg |= 0x18 | ad774x_conv_mode_table[i].reg_cfg;
 193                         ad774x_i2c_write(chip, AD774X_CFG, cfg);
 194                         return len;
 195                 }
 196         }
 197
 198         dev_err(dev, "not supported conversion mode\n");
 199
 200         return -EINVAL;
 201 }
 202
 203 static IIO_DEV_ATTR_CONVERSION_MODE(S_IRUGO | S_IWUSR,
 204                 ad774x_show_conversion_mode,
 205                 ad774x_store_conversion_mode);
 206
 207 static ssize_t ad774x_show_dac_value(struct device *dev,
 208                 struct device_attribute *attr,
 209                 char *buf)
 210 {
 211         struct iio_dev *dev_info = dev_get_drvdata(dev);
 212         struct ad774x_chip_info *chip = iio_priv(dev_info);
 213         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 214         u8 data;
 215
 216         ad774x_i2c_read(chip, this_attr->address, &data, 1);
 217
 218         return sprintf(buf, "%02x\n", data & 0x7F);
 219 }
 220
 221 static ssize_t ad774x_store_dac_value(struct device *dev,
 222                 struct device_attribute *attr,
 223                 const char *buf,
 224                 size_t len)
 225 {
 226         struct iio_dev *dev_info = dev_get_drvdata(dev);
 227         struct ad774x_chip_info *chip = iio_priv(dev_info);
 228         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 229         unsigned long data;
 230         int ret;
 231
 232         ret = strict_strtoul(buf, 10, &data);
 233
 234         if (!ret) {
 235                 ad774x_i2c_write(chip, this_attr->address,
 236                         (data ? AD774X_CAPDAC_EN : 0) | (data & 0x7F));
 237                 return len;
 238         }
 239
 240         return -EINVAL;
 241 }
 242
 243 static IIO_DEVICE_ATTR(capdac0_raw, S_IRUGO | S_IWUSR,
 244                         ad774x_show_dac_value,
 245                         ad774x_store_dac_value,
 246                         AD774X_CAPDACA);
 247
 248 static IIO_DEVICE_ATTR(capdac1_raw, S_IRUGO | S_IWUSR,
 249                         ad774x_show_dac_value,
 250                         ad774x_store_dac_value,
 251                         AD774X_CAPDACB);
 252
 253 static ssize_t ad774x_show_cap_setup(struct device *dev,
 254                 struct device_attribute *attr,
 255                 char *buf)
 256 {
 257         struct iio_dev *dev_info = dev_get_drvdata(dev);
 258         struct ad774x_chip_info *chip = iio_priv(dev_info);
 259
 260         return sprintf(buf, "0x%02x\n", chip->cap_setup);
 261 }
 262
 263 static ssize_t ad774x_store_cap_setup(struct device *dev,
 264                 struct device_attribute *attr,
 265                 const char *buf,
 266                 size_t len)
 267 {
 268         struct iio_dev *dev_info = dev_get_drvdata(dev);
 269         struct ad774x_chip_info *chip = iio_priv(dev_info);
 270         unsigned long data;
 271         int ret;
 272
 273         ret = strict_strtoul(buf, 10, &data);
 274
 275         if ((!ret) && (data < 0x100)) {
 276                 ad774x_i2c_write(chip, AD774X_CAP_SETUP, data);
 277                 chip->cap_setup = data;
 278                 return len;
 279         }
 280
 281         return -EINVAL;
 282 }
 283
 284 static IIO_DEV_ATTR_CAP_SETUP(S_IRUGO | S_IWUSR,
 285                 ad774x_show_cap_setup,
 286                 ad774x_store_cap_setup);
 287
 288 static ssize_t ad774x_show_vt_setup(struct device *dev,
 289                 struct device_attribute *attr,
 290                 char *buf)
 291 {
 292         struct iio_dev *dev_info = dev_get_drvdata(dev);
 293         struct ad774x_chip_info *chip = iio_priv(dev_info);
 294
 295         return sprintf(buf, "0x%02x\n", chip->vt_setup);
 296 }
 297
 298 static ssize_t ad774x_store_vt_setup(struct device *dev,
 299                 struct device_attribute *attr,
 300                 const char *buf,
 301                 size_t len)
 302 {
 303         struct iio_dev *dev_info = dev_get_drvdata(dev);
 304         struct ad774x_chip_info *chip = iio_priv(dev_info);
 305         unsigned long data;
 306         int ret;
 307
 308         ret = strict_strtoul(buf, 10, &data);
 309
 310         if ((!ret) && (data < 0x100)) {
 311                 ad774x_i2c_write(chip, AD774X_VT_SETUP, data);
 312                 chip->vt_setup = data;
 313                 return len;
 314         }
 315
 316         return -EINVAL;
 317 }
 318
 319 static IIO_DEV_ATTR_VT_SETUP(S_IRUGO | S_IWUSR,
 320                 ad774x_show_vt_setup,
 321                 ad774x_store_vt_setup);
 322
 323 static ssize_t ad774x_show_exec_setup(struct device *dev,
 324                 struct device_attribute *attr,
 325                 char *buf)
 326 {
 327         struct iio_dev *dev_info = dev_get_drvdata(dev);
 328         struct ad774x_chip_info *chip = iio_priv(dev_info);
 329
 330         return sprintf(buf, "0x%02x\n", chip->exec_setup);
 331 }
 332
 333 static ssize_t ad774x_store_exec_setup(struct device *dev,
 334                 struct device_attribute *attr,
 335                 const char *buf,
 336                 size_t len)
 337 {
 338         struct iio_dev *dev_info = dev_get_drvdata(dev);
 339         struct ad774x_chip_info *chip = iio_priv(dev_info);
 340         unsigned long data;
 341         int ret;
 342
 343         ret = strict_strtoul(buf, 10, &data);
 344
 345         if ((!ret) && (data < 0x100)) {
 346                 ad774x_i2c_write(chip, AD774X_EXEC_SETUP, data);
 347                 chip->exec_setup = data;
 348                 return len;
 349         }
 350
 351         return -EINVAL;
 352 }
 353
 354 static IIO_DEV_ATTR_EXEC_SETUP(S_IRUGO | S_IWUSR,
 355                 ad774x_show_exec_setup,
 356                 ad774x_store_exec_setup);
 357
 358 static ssize_t ad774x_show_volt_gain(struct device *dev,
 359                 struct device_attribute *attr,
 360                 char *buf)
 361 {
 362         struct iio_dev *dev_info = dev_get_drvdata(dev);
 363         struct ad774x_chip_info *chip = iio_priv(dev_info);
 364
 365         return sprintf(buf, "%d\n", chip->volt_gain);
 366 }
 367
 368 static ssize_t ad774x_store_volt_gain(struct device *dev,
 369                 struct device_attribute *attr,
 370                 const char *buf,
 371                 size_t len)
 372 {
 373         struct iio_dev *dev_info = dev_get_drvdata(dev);
 374         struct ad774x_chip_info *chip = iio_priv(dev_info);
 375         unsigned long data;
 376         int ret;
 377
 378         ret = strict_strtoul(buf, 10, &data);
 379
 380         if ((!ret) && (data < 0x10000)) {
 381                 ad774x_i2c_write(chip, AD774X_VOLT_GAINH, data >> 8);
 382                 ad774x_i2c_write(chip, AD774X_VOLT_GAINL, data);
 383                 chip->volt_gain = data;
 384                 return len;
 385         }
 386
 387         return -EINVAL;
 388 }
 389
 390 static IIO_DEV_ATTR_VOLT_GAIN(S_IRUGO | S_IWUSR,
 391                 ad774x_show_volt_gain,
 392                 ad774x_store_volt_gain);
 393
 394 static ssize_t ad774x_show_cap_data(struct device *dev,
 395                 struct device_attribute *attr,
 396                 char *buf)
 397 {
 398         struct iio_dev *dev_info = dev_get_drvdata(dev);
 399         struct ad774x_chip_info *chip = iio_priv(dev_info);
 400         unsigned long data;
 401         char tmp[3];
 402
 403         ad774x_i2c_read(chip, AD774X_CAP_DATA_HIGH, tmp, 3);
 404         data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
 405
 406         return sprintf(buf, "%ld\n", data);
 407 }
 408
 409 static IIO_DEV_ATTR_CAP_DATA(ad774x_show_cap_data);
 410
 411 static ssize_t ad774x_show_vt_data(struct device *dev,
 412                 struct device_attribute *attr,
 413                 char *buf)
 414 {
 415         struct iio_dev *dev_info = dev_get_drvdata(dev);
 416         struct ad774x_chip_info *chip = iio_priv(dev_info);
 417         unsigned long data;
 418         char tmp[3];
 419
 420         ad774x_i2c_read(chip, AD774X_VT_DATA_HIGH, tmp, 3);
 421         data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
 422
 423         return sprintf(buf, "%ld\n", data);
 424 }
 425
 426 static IIO_DEV_ATTR_VT_DATA(ad774x_show_vt_data);
 427
 428 static ssize_t ad774x_show_cap_offs(struct device *dev,
 429                 struct device_attribute *attr,
 430                 char *buf)
 431 {
 432         struct iio_dev *dev_info = dev_get_drvdata(dev);
 433         struct ad774x_chip_info *chip = iio_priv(dev_info);
 434
 435         return sprintf(buf, "%d\n", chip->cap_offs);
 436 }
 437
 438 static ssize_t ad774x_store_cap_offs(struct device *dev,
 439                 struct device_attribute *attr,
 440                 const char *buf,
 441                 size_t len)
 442 {
 443         struct iio_dev *dev_info = dev_get_drvdata(dev);
 444         struct ad774x_chip_info *chip = iio_priv(dev_info);
 445         unsigned long data;
 446         int ret;
 447
 448         ret = strict_strtoul(buf, 10, &data);
 449
 450         if ((!ret) && (data < 0x10000)) {
 451                 ad774x_i2c_write(chip, AD774X_CAP_OFFH, data >> 8);
 452                 ad774x_i2c_write(chip, AD774X_CAP_OFFL, data);
 453                 chip->cap_offs = data;
 454                 return len;
 455         }
 456
 457         return -EINVAL;
 458 }
 459
 460 static IIO_DEV_ATTR_CAP_OFFS(S_IRUGO | S_IWUSR,
 461                 ad774x_show_cap_offs,
 462                 ad774x_store_cap_offs);
 463
 464 static ssize_t ad774x_show_cap_gain(struct device *dev,
 465                 struct device_attribute *attr,
 466                 char *buf)
 467 {
 468         struct iio_dev *dev_info = dev_get_drvdata(dev);
 469         struct ad774x_chip_info *chip = iio_priv(dev_info);
 470
 471         return sprintf(buf, "%d\n", chip->cap_gain);
 472 }
 473
 474 static ssize_t ad774x_store_cap_gain(struct device *dev,
 475                 struct device_attribute *attr,
 476                 const char *buf,
 477                 size_t len)
 478 {
 479         struct iio_dev *dev_info = dev_get_drvdata(dev);
 480         struct ad774x_chip_info *chip = iio_priv(dev_info);
 481         unsigned long data;
 482         int ret;
 483
 484         ret = strict_strtoul(buf, 10, &data);
 485
 486         if ((!ret) && (data < 0x10000)) {
 487                 ad774x_i2c_write(chip, AD774X_CAP_GAINH, data >> 8);
 488                 ad774x_i2c_write(chip, AD774X_CAP_GAINL, data);
 489                 chip->cap_gain = data;
 490                 return len;
 491         }
 492
 493         return -EINVAL;
 494 }
 495
 496 static IIO_DEV_ATTR_CAP_GAIN(S_IRUGO | S_IWUSR,
 497                 ad774x_show_cap_gain,
 498                 ad774x_store_cap_gain);
 499
 500 static struct attribute *ad774x_attributes[] = {
 501         &iio_dev_attr_available_conversion_modes.dev_attr.attr,
 502         &iio_dev_attr_conversion_mode.dev_attr.attr,
 503         &iio_dev_attr_cap_setup.dev_attr.attr,
 504         &iio_dev_attr_in0_setup.dev_attr.attr,
 505         &iio_dev_attr_exec_setup.dev_attr.attr,
 506         &iio_dev_attr_cap_offs.dev_attr.attr,
 507         &iio_dev_attr_cap_gain.dev_attr.attr,
 508         &iio_dev_attr_in0_gain.dev_attr.attr,
 509         &iio_dev_attr_in0_raw.dev_attr.attr,
 510         &iio_dev_attr_cap0_raw.dev_attr.attr,
 511         &iio_dev_attr_capdac0_raw.dev_attr.attr,
 512         &iio_dev_attr_capdac1_raw.dev_attr.attr,
 513         NULL,
 514 };
 515
 516 static const struct attribute_group ad774x_attribute_group = {
 517         .attrs = ad774x_attributes,
 518 };
 519
 520 /*
 521  * data ready events
 522  */
 523
 524 #define IIO_EVENT_CODE_CAP_RDY     0
 525 #define IIO_EVENT_CODE_VT_RDY      1
 526
 527 #define IIO_EVENT_ATTR_CAP_RDY_SH(_evlist, _show, _store, _mask)        \
 528         IIO_EVENT_ATTR_SH(cap_rdy, _evlist, _show, _store, _mask)
 529
 530 #define IIO_EVENT_ATTR_VT_RDY_SH(_evlist, _show, _store, _mask) \
 531         IIO_EVENT_ATTR_SH(vt_rdy, _evlist, _show, _store, _mask)
 532
 533 static irqreturn_t ad774x_event_handler(int irq, void *private)
 534 {
 535         struct iio_dev *indio_dev = private;
 536         struct ad774x_chip_info *chip = iio_priv(indio_dev);
 537         u8 int_status;
 538
 539         ad774x_i2c_read(chip, AD774X_STATUS, &int_status, 1);
 540
 541         if (int_status & AD774X_STATUS_RDYCAP)
 542                 iio_push_event(indio_dev, 0,
 543                                IIO_EVENT_CODE_CAP_RDY,
 544                                iio_get_time_ns());
 545
 546         if (int_status & AD774X_STATUS_RDYVT)
 547                 iio_push_event(indio_dev, 0,
 548                                IIO_EVENT_CODE_VT_RDY,
 549                                iio_get_time_ns());
 550
 551         return IRQ_HANDLED;
 552 }
 553
 554 static IIO_CONST_ATTR(cap_rdy_en, "1");
 555 static IIO_CONST_ATTR(vt_rdy_en, "1");
 556
 557 static struct attribute *ad774x_event_attributes[] = {
 558         &iio_const_attr_cap_rdy_en.dev_attr.attr,
 559         &iio_const_attr_vt_rdy_en.dev_attr.attr,
 560         NULL,
 561 };
 562
 563 static struct attribute_group ad774x_event_attribute_group = {
 564         .attrs = ad774x_event_attributes,
 565 };
 566
 567 static const struct iio_info ad774x_info = {
 568         .attrs = &ad774x_event_attribute_group,
 569         .event_attrs = &ad774x_event_attribute_group,
 570         .num_interrupt_lines = 1,
 571         .driver_module = THIS_MODULE,
 572 };
 573 /*
 574  * device probe and remove
 575  */
 576
 577 static int __devinit ad774x_probe(struct i2c_client *client,
 578                 const struct i2c_device_id *id)
 579 {
 580         int ret = 0, regdone = 0;
 581         struct ad774x_chip_info *chip;
 582         struct iio_dev *indio_dev;
 583
 584         indio_dev = iio_allocate_device(sizeof(*chip));
 585         if (indio_dev == NULL) {
 586                 ret = -ENOMEM;
 587                 goto error_ret;
 588         }
 589         chip = iio_priv(indio_dev);
 590         /* this is only used for device removal purposes */
 591         i2c_set_clientdata(client, indio_dev);
 592
 593         chip->client = client;
 594
 595         /* Establish that the iio_dev is a child of the i2c device */
 596         indio_dev->name = id->name;
 597         indio_dev->dev.parent = &client->dev;
 598         indio_dev->info = &ad774x_info;
 599         indio_dev->modes = INDIO_DIRECT_MODE;
 600
 601         ret = iio_device_register(indio_dev);
 602         if (ret)
 603                 goto error_free_dev;
 604         regdone = 1;
 605
 606         if (client->irq) {
 607                 ret = request_threaded_irq(client->irq,
 608                                            NULL,
 609                                            &ad774x_event_handler,
 610                                            IRQF_TRIGGER_FALLING,
 611                                            "ad774x",
 612                                            indio_dev);
 613                 if (ret)
 614                         goto error_free_dev;
 615         }
 616
 617         dev_err(&client->dev, "%s capacitive sensor registered, irq: %d\n", id->name, client->irq);
 618
 619         return 0;
 620
 621 error_free_dev:
 622         if (regdone)
 623                 free_irq(client->irq, indio_dev);
 624         else
 625                 iio_free_device(indio_dev);
 626 error_ret:
 627         return ret;
 628 }
 629
 630 static int __devexit ad774x_remove(struct i2c_client *client)
 631 {
 632         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 633
 634         if (client->irq)
 635                 free_irq(client->irq, indio_dev);
 636         iio_device_unregister(indio_dev);
 637
 638         return 0;
 639 }
 640
 641 static const struct i2c_device_id ad774x_id[] = {
 642         { "ad7745", 0 },
 643         { "ad7746", 0 },
 644         { "ad7747", 0 },
 645         {}
 646 };
 647
 648 MODULE_DEVICE_TABLE(i2c, ad774x_id);
 649
 650 static struct i2c_driver ad774x_driver = {
 651         .driver = {
 652                 .name = "ad774x",
 653         },
 654         .probe = ad774x_probe,
 655         .remove = __devexit_p(ad774x_remove),
 656         .id_table = ad774x_id,
 657 };
 658
 659 static __init int ad774x_init(void)
 660 {
 661         return i2c_add_driver(&ad774x_driver);
 662 }
 663
 664 static __exit void ad774x_exit(void)
 665 {
 666         i2c_del_driver(&ad774x_driver);
 667 }
 668
 669 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 670 MODULE_DESCRIPTION("Analog Devices ad7745/6/7 capacitive sensor driver");
 671 MODULE_LICENSE("GPL v2");
 672
 673 module_init(ad774x_init);
 674 module_exit(ad774x_exit);