kernel/drivers/staging/iio/cdc/ad7150.c

   1 /*
   2  * AD7150 capacitive sensor driver supporting AD7150/1/6
   3  *
   4  * Copyright 2010-2011 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2 or later.
   7  */
   8
   9 #include <linux/interrupt.h>
  10 #include <linux/device.h>
  11 #include <linux/kernel.h>
  12 #include <linux/slab.h>
  13 #include <linux/i2c.h>
  14 #include <linux/module.h>
  15
  16 #include <linux/iio/iio.h>
  17 #include <linux/iio/sysfs.h>
  18 #include <linux/iio/events.h>
  19 /*
  20  * AD7150 registers definition
  21  */
  22
  23 #define AD7150_STATUS              0
  24 #define AD7150_STATUS_OUT1         (1 << 3)
  25 #define AD7150_STATUS_OUT2         (1 << 5)
  26 #define AD7150_CH1_DATA_HIGH       1
  27 #define AD7150_CH2_DATA_HIGH       3
  28 #define AD7150_CH1_AVG_HIGH        5
  29 #define AD7150_CH2_AVG_HIGH        7
  30 #define AD7150_CH1_SENSITIVITY     9
  31 #define AD7150_CH1_THR_HOLD_H      9
  32 #define AD7150_CH1_TIMEOUT         10
  33 #define AD7150_CH1_SETUP           11
  34 #define AD7150_CH2_SENSITIVITY     12
  35 #define AD7150_CH2_THR_HOLD_H      12
  36 #define AD7150_CH2_TIMEOUT         13
  37 #define AD7150_CH2_SETUP           14
  38 #define AD7150_CFG                 15
  39 #define AD7150_CFG_FIX             (1 << 7)
  40 #define AD7150_PD_TIMER            16
  41 #define AD7150_CH1_CAPDAC          17
  42 #define AD7150_CH2_CAPDAC          18
  43 #define AD7150_SN3                 19
  44 #define AD7150_SN2                 20
  45 #define AD7150_SN1                 21
  46 #define AD7150_SN0                 22
  47 #define AD7150_ID                  23
  48
  49 /**
  50  * struct ad7150_chip_info - instance specific chip data
  51  * @client: i2c client for this device
  52  * @current_event: device always has one type of event enabled.
  53  *      This element stores the event code of the current one.
  54  * @threshold: thresholds for simple capacitance value events
  55  * @thresh_sensitivity: threshold for simple capacitance offset
  56  *      from 'average' value.
  57  * @mag_sensitity: threshold for magnitude of capacitance offset from
  58  *      from 'average' value.
  59  * @thresh_timeout: a timeout, in samples from the moment an
  60  *      adaptive threshold event occurs to when the average
  61  *      value jumps to current value.
  62  * @mag_timeout: a timeout, in sample from the moment an
  63  *      adaptive magnitude event occurs to when the average
  64  *      value jumps to the current value.
  65  * @old_state: store state from previous event, allowing confirmation
  66  *      of new condition.
  67  * @conversion_mode: the current conversion mode.
  68  * @state_lock: ensure consistent state of this structure wrt the
  69  *      hardware.
  70  */
  71 struct ad7150_chip_info {
  72         struct i2c_client *client;
  73         u64 current_event;
  74         u16 threshold[2][2];
  75         u8 thresh_sensitivity[2][2];
  76         u8 mag_sensitivity[2][2];
  77         u8 thresh_timeout[2][2];
  78         u8 mag_timeout[2][2];
  79         int old_state;
  80         char *conversion_mode;
  81         struct mutex state_lock;
  82 };
  83
  84 /*
  85  * sysfs nodes
  86  */
  87
  88 static const u8 ad7150_addresses[][6] = {
  89         { AD7150_CH1_DATA_HIGH, AD7150_CH1_AVG_HIGH,
  90           AD7150_CH1_SETUP, AD7150_CH1_THR_HOLD_H,
  91           AD7150_CH1_SENSITIVITY, AD7150_CH1_TIMEOUT },
  92         { AD7150_CH2_DATA_HIGH, AD7150_CH2_AVG_HIGH,
  93           AD7150_CH2_SETUP, AD7150_CH2_THR_HOLD_H,
  94           AD7150_CH2_SENSITIVITY, AD7150_CH2_TIMEOUT },
  95 };
  96
  97 static int ad7150_read_raw(struct iio_dev *indio_dev,
  98                            struct iio_chan_spec const *chan,
  99                            int *val,
 100                            int *val2,
 101                            long mask)
 102 {
 103         int ret;
 104         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 105
 106         switch (mask) {
 107         case IIO_CHAN_INFO_RAW:
 108                 ret = i2c_smbus_read_word_data(chip->client,
 109                                         ad7150_addresses[chan->channel][0]);
 110                 if (ret < 0)
 111                         return ret;
 112                 *val = swab16(ret);
 113                 return IIO_VAL_INT;
 114         case IIO_CHAN_INFO_AVERAGE_RAW:
 115                 ret = i2c_smbus_read_word_data(chip->client,
 116                                         ad7150_addresses[chan->channel][1]);
 117                 if (ret < 0)
 118                         return ret;
 119                 *val = swab16(ret);
 120                 return IIO_VAL_INT;
 121         default:
 122                 return -EINVAL;
 123         }
 124 }
 125
 126 static int ad7150_read_event_config(struct iio_dev *indio_dev,
 127         const struct iio_chan_spec *chan, enum iio_event_type type,
 128         enum iio_event_direction dir)
 129 {
 130         int ret;
 131         u8 threshtype;
 132         bool adaptive;
 133         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 134
 135         ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG);
 136         if (ret < 0)
 137                 return ret;
 138
 139         threshtype = (ret >> 5) & 0x03;
 140         adaptive = !!(ret & 0x80);
 141
 142         switch (type) {
 143         case IIO_EV_TYPE_MAG_ADAPTIVE:
 144                 if (dir == IIO_EV_DIR_RISING)
 145                         return adaptive && (threshtype == 0x1);
 146                 return adaptive && (threshtype == 0x0);
 147         case IIO_EV_TYPE_THRESH_ADAPTIVE:
 148                 if (dir == IIO_EV_DIR_RISING)
 149                         return adaptive && (threshtype == 0x3);
 150                 return adaptive && (threshtype == 0x2);
 151         case IIO_EV_TYPE_THRESH:
 152                 if (dir == IIO_EV_DIR_RISING)
 153                         return !adaptive && (threshtype == 0x1);
 154                 return !adaptive && (threshtype == 0x0);
 155         default:
 156                 break;
 157         }
 158         return -EINVAL;
 159 }
 160
 161 /* lock should be held */
 162 static int ad7150_write_event_params(struct iio_dev *indio_dev,
 163          unsigned int chan, enum iio_event_type type,
 164          enum iio_event_direction dir)
 165 {
 166         int ret;
 167         u16 value;
 168         u8 sens, timeout;
 169         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 170         int rising = (dir == IIO_EV_DIR_RISING);
 171         u64 event_code;
 172
 173         event_code = IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE, chan, type, dir);
 174
 175         if (event_code != chip->current_event)
 176                 return 0;
 177
 178         switch (type) {
 179                 /* Note completely different from the adaptive versions */
 180         case IIO_EV_TYPE_THRESH:
 181                 value = chip->threshold[rising][chan];
 182                 return i2c_smbus_write_word_data(chip->client,
 183                                                 ad7150_addresses[chan][3],
 184                                                 swab16(value));
 185         case IIO_EV_TYPE_MAG_ADAPTIVE:
 186                 sens = chip->mag_sensitivity[rising][chan];
 187                 timeout = chip->mag_timeout[rising][chan];
 188                 break;
 189         case IIO_EV_TYPE_THRESH_ADAPTIVE:
 190                 sens = chip->thresh_sensitivity[rising][chan];
 191                 timeout = chip->thresh_timeout[rising][chan];
 192                 break;
 193         default:
 194                 return -EINVAL;
 195         }
 196         ret = i2c_smbus_write_byte_data(chip->client,
 197                                         ad7150_addresses[chan][4],
 198                                         sens);
 199         if (ret < 0)
 200                 return ret;
 201
 202         ret = i2c_smbus_write_byte_data(chip->client,
 203                                         ad7150_addresses[chan][5],
 204                                         timeout);
 205         if (ret < 0)
 206                 return ret;
 207
 208         return 0;
 209 }
 210
 211 static int ad7150_write_event_config(struct iio_dev *indio_dev,
 212         const struct iio_chan_spec *chan, enum iio_event_type type,
 213         enum iio_event_direction dir, int state)
 214 {
 215         u8 thresh_type, cfg, adaptive;
 216         int ret;
 217         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 218         int rising = (dir == IIO_EV_DIR_RISING);
 219         u64 event_code;
 220
 221         /* Something must always be turned on */
 222         if (!state)
 223                 return -EINVAL;
 224
 225         event_code = IIO_UNMOD_EVENT_CODE(chan->type, chan->channel, type, dir);
 226         if (event_code == chip->current_event)
 227                 return 0;
 228         mutex_lock(&chip->state_lock);
 229         ret = i2c_smbus_read_byte_data(chip->client, AD7150_CFG);
 230         if (ret < 0)
 231                 goto error_ret;
 232
 233         cfg = ret & ~((0x03 << 5) | (0x1 << 7));
 234
 235         switch (type) {
 236         case IIO_EV_TYPE_MAG_ADAPTIVE:
 237                 adaptive = 1;
 238                 if (rising)
 239                         thresh_type = 0x1;
 240                 else
 241                         thresh_type = 0x0;
 242                 break;
 243         case IIO_EV_TYPE_THRESH_ADAPTIVE:
 244                 adaptive = 1;
 245                 if (rising)
 246                         thresh_type = 0x3;
 247                 else
 248                         thresh_type = 0x2;
 249                 break;
 250         case IIO_EV_TYPE_THRESH:
 251                 adaptive = 0;
 252                 if (rising)
 253                         thresh_type = 0x1;
 254                 else
 255                         thresh_type = 0x0;
 256                 break;
 257         default:
 258                 ret = -EINVAL;
 259                 goto error_ret;
 260         }
 261
 262         cfg |= (!adaptive << 7) | (thresh_type << 5);
 263
 264         ret = i2c_smbus_write_byte_data(chip->client, AD7150_CFG, cfg);
 265         if (ret < 0)
 266                 goto error_ret;
 267
 268         chip->current_event = event_code;
 269
 270         /* update control attributes */
 271         ret = ad7150_write_event_params(indio_dev, chan->channel, type, dir);
 272 error_ret:
 273         mutex_unlock(&chip->state_lock);
 274
 275         return 0;
 276 }
 277
 278 static int ad7150_read_event_value(struct iio_dev *indio_dev,
 279                                    const struct iio_chan_spec *chan,
 280                                    enum iio_event_type type,
 281                                    enum iio_event_direction dir,
 282                                    enum iio_event_info info,
 283                                    int *val, int *val2)
 284 {
 285         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 286         int rising = (dir == IIO_EV_DIR_RISING);
 287
 288         /* Complex register sharing going on here */
 289         switch (type) {
 290         case IIO_EV_TYPE_MAG_ADAPTIVE:
 291                 *val = chip->mag_sensitivity[rising][chan->channel];
 292                 return IIO_VAL_INT;
 293         case IIO_EV_TYPE_THRESH_ADAPTIVE:
 294                 *val = chip->thresh_sensitivity[rising][chan->channel];
 295                 return IIO_VAL_INT;
 296         case IIO_EV_TYPE_THRESH:
 297                 *val = chip->threshold[rising][chan->channel];
 298                 return IIO_VAL_INT;
 299         default:
 300                 return -EINVAL;
 301         }
 302 }
 303
 304 static int ad7150_write_event_value(struct iio_dev *indio_dev,
 305                                    const struct iio_chan_spec *chan,
 306                                    enum iio_event_type type,
 307                                    enum iio_event_direction dir,
 308                                    enum iio_event_info info,
 309                                    int val, int val2)
 310 {
 311         int ret;
 312         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 313         int rising = (dir == IIO_EV_DIR_RISING);
 314
 315         mutex_lock(&chip->state_lock);
 316         switch (type) {
 317         case IIO_EV_TYPE_MAG_ADAPTIVE:
 318                 chip->mag_sensitivity[rising][chan->channel] = val;
 319                 break;
 320         case IIO_EV_TYPE_THRESH_ADAPTIVE:
 321                 chip->thresh_sensitivity[rising][chan->channel] = val;
 322                 break;
 323         case IIO_EV_TYPE_THRESH:
 324                 chip->threshold[rising][chan->channel] = val;
 325                 break;
 326         default:
 327                 ret = -EINVAL;
 328                 goto error_ret;
 329         }
 330
 331         /* write back if active */
 332         ret = ad7150_write_event_params(indio_dev, chan->channel, type, dir);
 333
 334 error_ret:
 335         mutex_unlock(&chip->state_lock);
 336         return ret;
 337 }
 338
 339 static ssize_t ad7150_show_timeout(struct device *dev,
 340                                    struct device_attribute *attr,
 341                                    char *buf)
 342 {
 343         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 344         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 345         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 346         u8 value;
 347
 348         /* use the event code for consistency reasons */
 349         int chan = IIO_EVENT_CODE_EXTRACT_CHAN(this_attr->address);
 350         int rising = !!(IIO_EVENT_CODE_EXTRACT_DIR(this_attr->address)
 351                         == IIO_EV_DIR_RISING);
 352
 353         switch (IIO_EVENT_CODE_EXTRACT_TYPE(this_attr->address)) {
 354         case IIO_EV_TYPE_MAG_ADAPTIVE:
 355                 value = chip->mag_timeout[rising][chan];
 356                 break;
 357         case IIO_EV_TYPE_THRESH_ADAPTIVE:
 358                 value = chip->thresh_timeout[rising][chan];
 359                 break;
 360         default:
 361                 return -EINVAL;
 362         }
 363
 364         return sprintf(buf, "%d\n", value);
 365 }
 366
 367 static ssize_t ad7150_store_timeout(struct device *dev,
 368                 struct device_attribute *attr,
 369                 const char *buf,
 370                 size_t len)
 371 {
 372         struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 373         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 374         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 375         int chan = IIO_EVENT_CODE_EXTRACT_CHAN(this_attr->address);
 376         enum iio_event_direction dir;
 377         enum iio_event_type type;
 378         int rising;
 379         u8 data;
 380         int ret;
 381
 382         type = IIO_EVENT_CODE_EXTRACT_TYPE(this_attr->address);
 383         dir = IIO_EVENT_CODE_EXTRACT_DIR(this_attr->address);
 384         rising = (dir == IIO_EV_DIR_RISING);
 385
 386         ret = kstrtou8(buf, 10, &data);
 387         if (ret < 0)
 388                 return ret;
 389
 390         mutex_lock(&chip->state_lock);
 391         switch (type) {
 392         case IIO_EV_TYPE_MAG_ADAPTIVE:
 393                 chip->mag_timeout[rising][chan] = data;
 394                 break;
 395         case IIO_EV_TYPE_THRESH_ADAPTIVE:
 396                 chip->thresh_timeout[rising][chan] = data;
 397                 break;
 398         default:
 399                 ret = -EINVAL;
 400                 goto error_ret;
 401         }
 402
 403         ret = ad7150_write_event_params(indio_dev, chan, type, dir);
 404 error_ret:
 405         mutex_unlock(&chip->state_lock);
 406
 407         if (ret < 0)
 408                 return ret;
 409
 410         return len;
 411 }
 412
 413 #define AD7150_TIMEOUT(chan, type, dir, ev_type, ev_dir)                \
 414         IIO_DEVICE_ATTR(in_capacitance##chan##_##type##_##dir##_timeout, \
 415                 S_IRUGO | S_IWUSR,                                      \
 416                 &ad7150_show_timeout,                                   \
 417                 &ad7150_store_timeout,                                  \
 418                 IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,                   \
 419                                      chan,                              \
 420                                      IIO_EV_TYPE_##ev_type,             \
 421                                      IIO_EV_DIR_##ev_dir))
 422 static AD7150_TIMEOUT(0, mag_adaptive, rising, MAG_ADAPTIVE, RISING);
 423 static AD7150_TIMEOUT(0, mag_adaptive, falling, MAG_ADAPTIVE, FALLING);
 424 static AD7150_TIMEOUT(1, mag_adaptive, rising, MAG_ADAPTIVE, RISING);
 425 static AD7150_TIMEOUT(1, mag_adaptive, falling, MAG_ADAPTIVE, FALLING);
 426 static AD7150_TIMEOUT(0, thresh_adaptive, rising, THRESH_ADAPTIVE, RISING);
 427 static AD7150_TIMEOUT(0, thresh_adaptive, falling, THRESH_ADAPTIVE, FALLING);
 428 static AD7150_TIMEOUT(1, thresh_adaptive, rising, THRESH_ADAPTIVE, RISING);
 429 static AD7150_TIMEOUT(1, thresh_adaptive, falling, THRESH_ADAPTIVE, FALLING);
 430
 431 static const struct iio_event_spec ad7150_events[] = {
 432         {
 433                 .type = IIO_EV_TYPE_THRESH,
 434                 .dir = IIO_EV_DIR_RISING,
 435                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 436                         BIT(IIO_EV_INFO_ENABLE),
 437         }, {
 438                 .type = IIO_EV_TYPE_THRESH,
 439                 .dir = IIO_EV_DIR_FALLING,
 440                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 441                         BIT(IIO_EV_INFO_ENABLE),
 442         }, {
 443                 .type = IIO_EV_TYPE_THRESH_ADAPTIVE,
 444                 .dir = IIO_EV_DIR_RISING,
 445                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 446                         BIT(IIO_EV_INFO_ENABLE),
 447         }, {
 448                 .type = IIO_EV_TYPE_THRESH_ADAPTIVE,
 449                 .dir = IIO_EV_DIR_FALLING,
 450                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 451                         BIT(IIO_EV_INFO_ENABLE),
 452         }, {
 453                 .type = IIO_EV_TYPE_MAG_ADAPTIVE,
 454                 .dir = IIO_EV_DIR_RISING,
 455                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 456                         BIT(IIO_EV_INFO_ENABLE),
 457         }, {
 458                 .type = IIO_EV_TYPE_MAG_ADAPTIVE,
 459                 .dir = IIO_EV_DIR_FALLING,
 460                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 461                         BIT(IIO_EV_INFO_ENABLE),
 462         },
 463 };
 464
 465 static const struct iio_chan_spec ad7150_channels[] = {
 466         {
 467                 .type = IIO_CAPACITANCE,
 468                 .indexed = 1,
 469                 .channel = 0,
 470                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 471                 BIT(IIO_CHAN_INFO_AVERAGE_RAW),
 472                 .event_spec = ad7150_events,
 473                 .num_event_specs = ARRAY_SIZE(ad7150_events),
 474         }, {
 475                 .type = IIO_CAPACITANCE,
 476                 .indexed = 1,
 477                 .channel = 1,
 478                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 479                 BIT(IIO_CHAN_INFO_AVERAGE_RAW),
 480                 .event_spec = ad7150_events,
 481                 .num_event_specs = ARRAY_SIZE(ad7150_events),
 482         },
 483 };
 484
 485 /*
 486  * threshold events
 487  */
 488
 489 static irqreturn_t ad7150_event_handler(int irq, void *private)
 490 {
 491         struct iio_dev *indio_dev = private;
 492         struct ad7150_chip_info *chip = iio_priv(indio_dev);
 493         u8 int_status;
 494         s64 timestamp = iio_get_time_ns();
 495         int ret;
 496
 497         ret = i2c_smbus_read_byte_data(chip->client, AD7150_STATUS);
 498         if (ret < 0)
 499                 return IRQ_HANDLED;
 500
 501         int_status = ret;
 502
 503         if ((int_status & AD7150_STATUS_OUT1) &&
 504             !(chip->old_state & AD7150_STATUS_OUT1))
 505                 iio_push_event(indio_dev,
 506                                IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
 507                                                     0,
 508                                                     IIO_EV_TYPE_THRESH,
 509                                                     IIO_EV_DIR_RISING),
 510                                 timestamp);
 511         else if ((!(int_status & AD7150_STATUS_OUT1)) &&
 512                  (chip->old_state & AD7150_STATUS_OUT1))
 513                 iio_push_event(indio_dev,
 514                                IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
 515                                                     0,
 516                                                     IIO_EV_TYPE_THRESH,
 517                                                     IIO_EV_DIR_FALLING),
 518                                timestamp);
 519
 520         if ((int_status & AD7150_STATUS_OUT2) &&
 521             !(chip->old_state & AD7150_STATUS_OUT2))
 522                 iio_push_event(indio_dev,
 523                                IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
 524                                                     1,
 525                                                     IIO_EV_TYPE_THRESH,
 526                                                     IIO_EV_DIR_RISING),
 527                                timestamp);
 528         else if ((!(int_status & AD7150_STATUS_OUT2)) &&
 529                  (chip->old_state & AD7150_STATUS_OUT2))
 530                 iio_push_event(indio_dev,
 531                                IIO_UNMOD_EVENT_CODE(IIO_CAPACITANCE,
 532                                                     1,
 533                                                     IIO_EV_TYPE_THRESH,
 534                                                     IIO_EV_DIR_FALLING),
 535                                timestamp);
 536         /* store the status to avoid repushing same events */
 537         chip->old_state = int_status;
 538
 539         return IRQ_HANDLED;
 540 }
 541
 542 /* Timeouts not currently handled by core */
 543 static struct attribute *ad7150_event_attributes[] = {
 544         &iio_dev_attr_in_capacitance0_mag_adaptive_rising_timeout
 545         .dev_attr.attr,
 546         &iio_dev_attr_in_capacitance0_mag_adaptive_falling_timeout
 547         .dev_attr.attr,
 548         &iio_dev_attr_in_capacitance1_mag_adaptive_rising_timeout
 549         .dev_attr.attr,
 550         &iio_dev_attr_in_capacitance1_mag_adaptive_falling_timeout
 551         .dev_attr.attr,
 552         &iio_dev_attr_in_capacitance0_thresh_adaptive_rising_timeout
 553         .dev_attr.attr,
 554         &iio_dev_attr_in_capacitance0_thresh_adaptive_falling_timeout
 555         .dev_attr.attr,
 556         &iio_dev_attr_in_capacitance1_thresh_adaptive_rising_timeout
 557         .dev_attr.attr,
 558         &iio_dev_attr_in_capacitance1_thresh_adaptive_falling_timeout
 559         .dev_attr.attr,
 560         NULL,
 561 };
 562
 563 static struct attribute_group ad7150_event_attribute_group = {
 564         .attrs = ad7150_event_attributes,
 565         .name = "events",
 566 };
 567
 568 static const struct iio_info ad7150_info = {
 569         .event_attrs = &ad7150_event_attribute_group,
 570         .driver_module = THIS_MODULE,
 571         .read_raw = &ad7150_read_raw,
 572         .read_event_config = &ad7150_read_event_config,
 573         .write_event_config = &ad7150_write_event_config,
 574         .read_event_value = &ad7150_read_event_value,
 575         .write_event_value = &ad7150_write_event_value,
 576 };
 577
 578 /*
 579  * device probe and remove
 580  */
 581
 582 static int ad7150_probe(struct i2c_client *client,
 583                 const struct i2c_device_id *id)
 584 {
 585         int ret;
 586         struct ad7150_chip_info *chip;
 587         struct iio_dev *indio_dev;
 588
 589         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
 590         if (!indio_dev)
 591                 return -ENOMEM;
 592         chip = iio_priv(indio_dev);
 593         mutex_init(&chip->state_lock);
 594         /* this is only used for device removal purposes */
 595         i2c_set_clientdata(client, indio_dev);
 596
 597         chip->client = client;
 598
 599         indio_dev->name = id->name;
 600         indio_dev->channels = ad7150_channels;
 601         indio_dev->num_channels = ARRAY_SIZE(ad7150_channels);
 602         /* Establish that the iio_dev is a child of the i2c device */
 603         indio_dev->dev.parent = &client->dev;
 604
 605         indio_dev->info = &ad7150_info;
 606
 607         indio_dev->modes = INDIO_DIRECT_MODE;
 608
 609         if (client->irq) {
 610                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 611                                            NULL,
 612                                            &ad7150_event_handler,
 613                                            IRQF_TRIGGER_RISING |
 614                                            IRQF_TRIGGER_FALLING |
 615                                            IRQF_ONESHOT,
 616                                            "ad7150_irq1",
 617                                            indio_dev);
 618                 if (ret)
 619                         return ret;
 620         }
 621
 622         if (client->dev.platform_data) {
 623                 ret = devm_request_threaded_irq(&client->dev, *(unsigned int *)
 624                                            client->dev.platform_data,
 625                                            NULL,
 626                                            &ad7150_event_handler,
 627                                            IRQF_TRIGGER_RISING |
 628                                            IRQF_TRIGGER_FALLING |
 629                                            IRQF_ONESHOT,
 630                                            "ad7150_irq2",
 631                                            indio_dev);
 632                 if (ret)
 633                         return ret;
 634         }
 635
 636         ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
 637         if (ret)
 638                 return ret;
 639
 640         dev_info(&client->dev, "%s capacitive sensor registered,irq: %d\n",
 641                  id->name, client->irq);
 642
 643         return 0;
 644 }
 645
 646 static const struct i2c_device_id ad7150_id[] = {
 647         { "ad7150", 0 },
 648         { "ad7151", 0 },
 649         { "ad7156", 0 },
 650         {}
 651 };
 652
 653 MODULE_DEVICE_TABLE(i2c, ad7150_id);
 654
 655 static struct i2c_driver ad7150_driver = {
 656         .driver = {
 657                 .name = "ad7150",
 658         },
 659         .probe = ad7150_probe,
 660         .id_table = ad7150_id,
 661 };
 662 module_i2c_driver(ad7150_driver);
 663
 664 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
 665 MODULE_DESCRIPTION("Analog Devices AD7150/1/6 capacitive sensor driver");
 666 MODULE_LICENSE("GPL v2");