drivers/staging/iio/adc/ad7291.c

   1 /*
   2  * AD7291 8-Channel, I2C, 12-Bit SAR ADC with Temperature Sensor
   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/sysfs.h>
  14 #include <linux/i2c.h>
  15 #include <linux/module.h>
  16 #include <linux/mutex.h>
  17 #include <linux/regulator/consumer.h>
  18 #include <linux/err.h>
  19
  20 #include "../iio.h"
  21 #include "../sysfs.h"
  22 #include "../events.h"
  23
  24 /*
  25  * Simplified handling
  26  *
  27  * If no events enabled - single polled channel read
  28  * If event enabled direct reads disable unless channel
  29  * is in the read mask.
  30  *
  31  * The noise-delayed bit as per datasheet suggestion is always enabled.
  32  *
  33  */
  34
  35 /*
  36  * AD7291 registers definition
  37  */
  38 #define AD7291_COMMAND                  0x00
  39 #define AD7291_VOLTAGE                  0x01
  40 #define AD7291_T_SENSE                  0x02
  41 #define AD7291_T_AVERAGE                0x03
  42 #define AD7291_CH0_DATA_HIGH            0x04
  43 #define AD7291_CH0_DATA_LOW             0x05
  44 #define AD7291_CH0_HYST                 0x06
  45 #define AD7291_CH1_DATA_HIGH            0x07
  46 #define AD7291_CH1_DATA_LOW             0x08
  47 #define AD7291_CH1_HYST                 0x09
  48 #define AD7291_CH2_DATA_HIGH            0x0A
  49 #define AD7291_CH2_DATA_LOW             0x0B
  50 #define AD7291_CH2_HYST                 0x0C
  51 #define AD7291_CH3_DATA_HIGH            0x0D
  52 #define AD7291_CH3_DATA_LOW             0x0E
  53 #define AD7291_CH3_HYST                 0x0F
  54 #define AD7291_CH4_DATA_HIGH            0x10
  55 #define AD7291_CH4_DATA_LOW             0x11
  56 #define AD7291_CH4_HYST                 0x12
  57 #define AD7291_CH5_DATA_HIGH            0x13
  58 #define AD7291_CH5_DATA_LOW             0x14
  59 #define AD7291_CH5_HYST                 0x15
  60 #define AD7291_CH6_DATA_HIGH            0x16
  61 #define AD7291_CH6_DATA_LOW             0x17
  62 #define AD7291_CH6_HYST                 0x18
  63 #define AD7291_CH7_DATA_HIGH            0x19
  64 #define AD7291_CH7_DATA_LOW             0x1A
  65 #define AD7291_CH7_HYST                 0x2B
  66 #define AD7291_T_SENSE_HIGH             0x1C
  67 #define AD7291_T_SENSE_LOW              0x1D
  68 #define AD7291_T_SENSE_HYST             0x1E
  69 #define AD7291_VOLTAGE_ALERT_STATUS     0x1F
  70 #define AD7291_T_ALERT_STATUS           0x20
  71
  72 #define AD7291_VOLTAGE_LIMIT_COUNT      8
  73
  74
  75 /*
  76  * AD7291 command
  77  */
  78 #define AD7291_AUTOCYCLE                (1 << 0)
  79 #define AD7291_RESET                    (1 << 1)
  80 #define AD7291_ALERT_CLEAR              (1 << 2)
  81 #define AD7291_ALERT_POLARITY           (1 << 3)
  82 #define AD7291_EXT_REF                  (1 << 4)
  83 #define AD7291_NOISE_DELAY              (1 << 5)
  84 #define AD7291_T_SENSE_MASK             (1 << 7)
  85 #define AD7291_VOLTAGE_MASK             0xFF00
  86 #define AD7291_VOLTAGE_OFFSET           0x8
  87
  88 /*
  89  * AD7291 value masks
  90  */
  91 #define AD7291_CHANNEL_MASK             0xF000
  92 #define AD7291_BITS                     12
  93 #define AD7291_VALUE_MASK               0xFFF
  94 #define AD7291_T_VALUE_SIGN             0x400
  95 #define AD7291_T_VALUE_FLOAT_OFFSET     2
  96 #define AD7291_T_VALUE_FLOAT_MASK       0x2
  97
  98 #define AD7291_BITS                     12
  99
 100 struct ad7291_chip_info {
 101         struct i2c_client       *client;
 102         struct regulator        *reg;
 103         u16                     int_vref_mv;
 104         u16                     command;
 105         u16                     c_mask; /* Active voltage channels for events */
 106         struct mutex            state_lock;
 107 };
 108
 109 static int ad7291_i2c_read(struct ad7291_chip_info *chip, u8 reg, u16 *data)
 110 {
 111         struct i2c_client *client = chip->client;
 112         int ret = 0;
 113
 114         ret = i2c_smbus_read_word_data(client, reg);
 115         if (ret < 0) {
 116                 dev_err(&client->dev, "I2C read error\n");
 117                 return ret;
 118         }
 119
 120         *data = swab16((u16)ret);
 121
 122         return 0;
 123 }
 124
 125 static int ad7291_i2c_write(struct ad7291_chip_info *chip, u8 reg, u16 data)
 126 {
 127         return i2c_smbus_write_word_data(chip->client, reg, swab16(data));
 128 }
 129
 130 static ssize_t ad7291_store_reset(struct device *dev,
 131                 struct device_attribute *attr,
 132                 const char *buf,
 133                 size_t len)
 134 {
 135         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 136         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 137
 138         return ad7291_i2c_write(chip, AD7291_COMMAND,
 139                                 chip->command | AD7291_RESET);
 140 }
 141
 142 static IIO_DEVICE_ATTR(reset, S_IWUSR, NULL, ad7291_store_reset, 0);
 143
 144 static struct attribute *ad7291_attributes[] = {
 145         &iio_dev_attr_reset.dev_attr.attr,
 146         NULL,
 147 };
 148
 149 static const struct attribute_group ad7291_attribute_group = {
 150         .attrs = ad7291_attributes,
 151 };
 152
 153 static irqreturn_t ad7291_event_handler(int irq, void *private)
 154 {
 155         struct iio_dev *indio_dev = private;
 156         struct ad7291_chip_info *chip = iio_priv(private);
 157         u16 t_status, v_status;
 158         u16 command;
 159         int i;
 160         s64 timestamp = iio_get_time_ns();
 161
 162         if (ad7291_i2c_read(chip, AD7291_T_ALERT_STATUS, &t_status))
 163                 return IRQ_HANDLED;
 164
 165         if (ad7291_i2c_read(chip, AD7291_VOLTAGE_ALERT_STATUS, &v_status))
 166                 return IRQ_HANDLED;
 167
 168         if (!(t_status || v_status))
 169                 return IRQ_HANDLED;
 170
 171         command = chip->command | AD7291_ALERT_CLEAR;
 172         ad7291_i2c_write(chip, AD7291_COMMAND, command);
 173
 174         command = chip->command & ~AD7291_ALERT_CLEAR;
 175         ad7291_i2c_write(chip, AD7291_COMMAND, command);
 176
 177         /* For now treat t_sense and t_sense_average the same */
 178         if ((t_status & (1 << 0)) || (t_status & (1 << 2)))
 179                 iio_push_event(indio_dev,
 180                                IIO_UNMOD_EVENT_CODE(IIO_TEMP,
 181                                                     0,
 182                                                     IIO_EV_TYPE_THRESH,
 183                                                     IIO_EV_DIR_FALLING),
 184                                timestamp);
 185         if ((t_status & (1 << 1)) || (t_status & (1 << 3)))
 186                 iio_push_event(indio_dev,
 187                                IIO_UNMOD_EVENT_CODE(IIO_TEMP,
 188                                                     0,
 189                                                     IIO_EV_TYPE_THRESH,
 190                                                     IIO_EV_DIR_RISING),
 191                                timestamp);
 192
 193         for (i = 0; i < AD7291_VOLTAGE_LIMIT_COUNT*2; i += 2) {
 194                 if (v_status & (1 << i))
 195                         iio_push_event(indio_dev,
 196                                        IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
 197                                                             i/2,
 198                                                             IIO_EV_TYPE_THRESH,
 199                                                             IIO_EV_DIR_FALLING),
 200                                        timestamp);
 201                 if (v_status & (1 << (i + 1)))
 202                         iio_push_event(indio_dev,
 203                                        IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE,
 204                                                             i/2,
 205                                                             IIO_EV_TYPE_THRESH,
 206                                                             IIO_EV_DIR_RISING),
 207                                        timestamp);
 208         }
 209
 210         return IRQ_HANDLED;
 211 }
 212
 213 static inline ssize_t ad7291_show_hyst(struct device *dev,
 214                 struct device_attribute *attr,
 215                 char *buf)
 216 {
 217         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 218         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 219         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 220         u16 data;
 221         int ret;
 222
 223         ret = ad7291_i2c_read(chip, this_attr->address, &data);
 224         if (ret < 0)
 225                 return ret;
 226
 227         return sprintf(buf, "%d\n", data & AD7291_VALUE_MASK);
 228 }
 229
 230 static inline ssize_t ad7291_set_hyst(struct device *dev,
 231                                       struct device_attribute *attr,
 232                                       const char *buf,
 233                                       size_t len)
 234 {
 235         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 236         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 237         struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
 238         u16 data;
 239         int ret;
 240
 241         ret = kstrtou16(buf, 10, &data);
 242
 243         if (ret < 0)
 244                 return ret;
 245         if (data > AD7291_VALUE_MASK)
 246                 return -EINVAL;
 247
 248         ret = ad7291_i2c_write(chip, this_attr->address, data);
 249         if (ret < 0)
 250                 return ret;
 251
 252         return len;
 253 }
 254
 255 static IIO_DEVICE_ATTR(in_temp0_thresh_both_hyst_raw,
 256                        S_IRUGO | S_IWUSR,
 257                        ad7291_show_hyst, ad7291_set_hyst,
 258                        AD7291_T_SENSE_HYST);
 259 static IIO_DEVICE_ATTR(in_voltage0_thresh_both_hyst_raw,
 260                        S_IRUGO | S_IWUSR,
 261                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH0_HYST);
 262 static IIO_DEVICE_ATTR(in_voltage1_thresh_both_hyst_raw,
 263                        S_IRUGO | S_IWUSR,
 264                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH1_HYST);
 265 static IIO_DEVICE_ATTR(in_voltage2_thresh_both_hyst_raw,
 266                        S_IRUGO | S_IWUSR,
 267                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH2_HYST);
 268 static IIO_DEVICE_ATTR(in_voltage3_thresh_both_hyst_raw,
 269                        S_IRUGO | S_IWUSR,
 270                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH3_HYST);
 271 static IIO_DEVICE_ATTR(in_voltage4_thresh_both_hyst_raw,
 272                        S_IRUGO | S_IWUSR,
 273                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH4_HYST);
 274 static IIO_DEVICE_ATTR(in_voltage5_thresh_both_hyst_raw,
 275                        S_IRUGO | S_IWUSR,
 276                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH5_HYST);
 277 static IIO_DEVICE_ATTR(in_voltage6_thresh_both_hyst_raw,
 278                        S_IRUGO | S_IWUSR,
 279                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH6_HYST);
 280 static IIO_DEVICE_ATTR(in_voltage7_thresh_both_hyst_raw,
 281                        S_IRUGO | S_IWUSR,
 282                        ad7291_show_hyst, ad7291_set_hyst, AD7291_CH7_HYST);
 283
 284 static struct attribute *ad7291_event_attributes[] = {
 285         &iio_dev_attr_in_temp0_thresh_both_hyst_raw.dev_attr.attr,
 286         &iio_dev_attr_in_voltage0_thresh_both_hyst_raw.dev_attr.attr,
 287         &iio_dev_attr_in_voltage1_thresh_both_hyst_raw.dev_attr.attr,
 288         &iio_dev_attr_in_voltage2_thresh_both_hyst_raw.dev_attr.attr,
 289         &iio_dev_attr_in_voltage3_thresh_both_hyst_raw.dev_attr.attr,
 290         &iio_dev_attr_in_voltage4_thresh_both_hyst_raw.dev_attr.attr,
 291         &iio_dev_attr_in_voltage5_thresh_both_hyst_raw.dev_attr.attr,
 292         &iio_dev_attr_in_voltage6_thresh_both_hyst_raw.dev_attr.attr,
 293         &iio_dev_attr_in_voltage7_thresh_both_hyst_raw.dev_attr.attr,
 294         NULL,
 295 };
 296
 297 /* high / low */
 298 static u8 ad7291_limit_regs[9][2] = {
 299         { AD7291_CH0_DATA_HIGH, AD7291_CH0_DATA_LOW },
 300         { AD7291_CH1_DATA_HIGH, AD7291_CH1_DATA_LOW },
 301         { AD7291_CH2_DATA_HIGH, AD7291_CH2_DATA_LOW },
 302         { AD7291_CH3_DATA_HIGH, AD7291_CH3_DATA_LOW }, /* FIXME: ? */
 303         { AD7291_CH4_DATA_HIGH, AD7291_CH4_DATA_LOW },
 304         { AD7291_CH5_DATA_HIGH, AD7291_CH5_DATA_LOW },
 305         { AD7291_CH6_DATA_HIGH, AD7291_CH6_DATA_LOW },
 306         { AD7291_CH7_DATA_HIGH, AD7291_CH7_DATA_LOW },
 307         /* temp */
 308         { AD7291_T_SENSE_HIGH, AD7291_T_SENSE_LOW },
 309 };
 310
 311 static int ad7291_read_event_value(struct iio_dev *indio_dev,
 312                                    u64 event_code,
 313                                    int *val)
 314 {
 315         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 316
 317         int ret;
 318         u8 reg;
 319         u16 uval;
 320         s16 signval;
 321
 322         switch (IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event_code)) {
 323         case IIO_VOLTAGE:
 324                 reg = ad7291_limit_regs[IIO_EVENT_CODE_EXTRACT_NUM(event_code)]
 325                         [!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
 326                            IIO_EV_DIR_RISING)];
 327
 328                 ret = ad7291_i2c_read(chip, reg, &uval);
 329                 if (ret < 0)
 330                         return ret;
 331                 *val = uval & AD7291_VALUE_MASK;
 332                 return 0;
 333
 334         case IIO_TEMP:
 335                 reg = ad7291_limit_regs[8]
 336                         [!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
 337                            IIO_EV_DIR_RISING)];
 338
 339                 ret = ad7291_i2c_read(chip, reg, &signval);
 340                 if (ret < 0)
 341                         return ret;
 342                 signval = (s16)((signval & AD7291_VALUE_MASK) << 4) >> 4;
 343                 *val = signval;
 344                 return 0;
 345         default:
 346                 return -EINVAL;
 347         };
 348 }
 349
 350 static int ad7291_write_event_value(struct iio_dev *indio_dev,
 351                                     u64 event_code,
 352                                     int val)
 353 {
 354         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 355         u8 reg;
 356         s16 signval;
 357
 358         switch (IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event_code)) {
 359         case IIO_VOLTAGE:
 360                 if (val > AD7291_VALUE_MASK || val < 0)
 361                         return -EINVAL;
 362                 reg = ad7291_limit_regs[IIO_EVENT_CODE_EXTRACT_NUM(event_code)]
 363                         [!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
 364                            IIO_EV_DIR_RISING)];
 365                 return ad7291_i2c_write(chip, reg, val);
 366         case IIO_TEMP:
 367                 if (val > 2047 || val < -2048)
 368                         return -EINVAL;
 369                 reg = ad7291_limit_regs[8]
 370                         [!(IIO_EVENT_CODE_EXTRACT_DIR(event_code) ==
 371                            IIO_EV_DIR_RISING)];
 372                 signval = val;
 373                 return ad7291_i2c_write(chip, reg, *(u16 *)&signval);
 374         default:
 375                 return -EINVAL;
 376         };
 377 }
 378
 379 static int ad7291_read_event_config(struct iio_dev *indio_dev,
 380                                     u64 event_code)
 381 {
 382         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 383         /* To be enabled the channel must simply be on. If any are enabled
 384            we are in continuous sampling mode */
 385
 386         switch (IIO_EVENT_CODE_EXTRACT_CHAN_TYPE(event_code)) {
 387         case IIO_VOLTAGE:
 388                 if (chip->c_mask &
 389                     (1 << (15 - IIO_EVENT_CODE_EXTRACT_NUM(event_code))))
 390                         return 1;
 391                 else
 392                         return 0;
 393         case IIO_TEMP:
 394                 /* always on */
 395                 return 1;
 396         default:
 397                 return -EINVAL;
 398         }
 399
 400 }
 401
 402 static int ad7291_write_event_config(struct iio_dev *indio_dev,
 403                                      u64 event_code,
 404                                      int state)
 405 {
 406         int ret = 0;
 407         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 408         u16 regval;
 409
 410         mutex_lock(&chip->state_lock);
 411         regval = chip->command;
 412         /*
 413          * To be enabled the channel must simply be on. If any are enabled
 414          * use continuous sampling mode.
 415          * Possible to disable temp as well but that makes single read tricky.
 416          */
 417
 418         switch (IIO_EVENT_CODE_EXTRACT_TYPE(event_code)) {
 419         case IIO_VOLTAGE:
 420                 if ((!state) && (chip->c_mask & (1 << (15 -
 421                                 IIO_EVENT_CODE_EXTRACT_NUM(event_code)))))
 422                         chip->c_mask &= ~(1 << (15 - IIO_EVENT_CODE_EXTRACT_NUM
 423                                                         (event_code)));
 424                 else if (state && (!(chip->c_mask & (1 << (15 -
 425                                 IIO_EVENT_CODE_EXTRACT_NUM(event_code))))))
 426                         chip->c_mask |= (1 << (15 - IIO_EVENT_CODE_EXTRACT_NUM
 427                                                         (event_code)));
 428                 else
 429                         break;
 430
 431                 regval &= ~AD7291_AUTOCYCLE;
 432                 regval |= chip->c_mask;
 433                 if (chip->c_mask) /* Enable autocycle? */
 434                         regval |= AD7291_AUTOCYCLE;
 435
 436                 ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
 437                 if (ret < 0)
 438                         goto error_ret;
 439
 440                 chip->command = regval;
 441                 break;
 442         default:
 443                 ret = -EINVAL;
 444         }
 445
 446 error_ret:
 447         mutex_unlock(&chip->state_lock);
 448         return ret;
 449 }
 450
 451 static int ad7291_read_raw(struct iio_dev *indio_dev,
 452                            struct iio_chan_spec const *chan,
 453                            int *val,
 454                            int *val2,
 455                            long mask)
 456 {
 457         int ret;
 458         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 459         unsigned int scale_uv;
 460         u16 regval;
 461         s16 signval;
 462
 463         switch (mask) {
 464         case 0:
 465                 switch (chan->type) {
 466                 case IIO_VOLTAGE:
 467                         mutex_lock(&chip->state_lock);
 468                         /* If in autocycle mode drop through */
 469                         if (chip->command & AD7291_AUTOCYCLE) {
 470                                 mutex_unlock(&chip->state_lock);
 471                                 return -EBUSY;
 472                         }
 473                         /* Enable this channel alone */
 474                         regval = chip->command & (~AD7291_VOLTAGE_MASK);
 475                         regval |= 1 << (15 - chan->channel);
 476                         ret = ad7291_i2c_write(chip, AD7291_COMMAND, regval);
 477                         if (ret < 0) {
 478                                 mutex_unlock(&chip->state_lock);
 479                                 return ret;
 480                         }
 481                         /* Read voltage */
 482                         ret = i2c_smbus_read_word_data(chip->client,
 483                                                        AD7291_VOLTAGE);
 484                         if (ret < 0) {
 485                                 mutex_unlock(&chip->state_lock);
 486                                 return ret;
 487                         }
 488                         *val = swab16((u16)ret) & AD7291_VALUE_MASK;
 489                         mutex_unlock(&chip->state_lock);
 490                         return IIO_VAL_INT;
 491                 case IIO_TEMP:
 492                         /* Assumes tsense bit of command register always set */
 493                         ret = i2c_smbus_read_word_data(chip->client,
 494                                                        AD7291_T_SENSE);
 495                         if (ret < 0)
 496                                 return ret;
 497                         signval = (s16)((swab16((u16)ret) &
 498                                 AD7291_VALUE_MASK) << 4) >> 4;
 499                         *val = signval;
 500                         return IIO_VAL_INT;
 501                 default:
 502                         return -EINVAL;
 503                 }
 504         case IIO_CHAN_INFO_AVERAGE_RAW:
 505                 ret = i2c_smbus_read_word_data(chip->client,
 506                                                AD7291_T_AVERAGE);
 507                         if (ret < 0)
 508                                 return ret;
 509                         signval = (s16)((swab16((u16)ret) &
 510                                 AD7291_VALUE_MASK) << 4) >> 4;
 511                         *val = signval;
 512                         return IIO_VAL_INT;
 513         case IIO_CHAN_INFO_SCALE:
 514                 switch (chan->type) {
 515                 case IIO_VOLTAGE:
 516                         scale_uv = (chip->int_vref_mv * 1000) >> AD7291_BITS;
 517                         *val =  scale_uv / 1000;
 518                         *val2 = (scale_uv % 1000) * 1000;
 519                         return IIO_VAL_INT_PLUS_MICRO;
 520                 case IIO_TEMP:
 521                         /*
 522                          * One LSB of the ADC corresponds to 0.25 deg C.
 523                          * The temperature reading is in 12-bit twos
 524                          * complement format
 525                          */
 526                         *val = 250;
 527                         return IIO_VAL_INT;
 528                 default:
 529                         return -EINVAL;
 530                 }
 531         default:
 532                 return -EINVAL;
 533         }
 534 }
 535
 536 #define AD7291_VOLTAGE_CHAN(_chan)                                      \
 537 {                                                                       \
 538         .type = IIO_VOLTAGE,                                            \
 539         .info_mask = IIO_CHAN_INFO_SCALE_SHARED_BIT,                    \
 540         .indexed = 1,                                                   \
 541         .channel = _chan,                                               \
 542         .event_mask = IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING)|\
 543         IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_FALLING)              \
 544 }
 545
 546 static const struct iio_chan_spec ad7291_channels[] = {
 547         AD7291_VOLTAGE_CHAN(0),
 548         AD7291_VOLTAGE_CHAN(1),
 549         AD7291_VOLTAGE_CHAN(2),
 550         AD7291_VOLTAGE_CHAN(3),
 551         AD7291_VOLTAGE_CHAN(4),
 552         AD7291_VOLTAGE_CHAN(5),
 553         AD7291_VOLTAGE_CHAN(6),
 554         AD7291_VOLTAGE_CHAN(7),
 555         {
 556                 .type = IIO_TEMP,
 557                 .info_mask = IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE_BIT |
 558                                 IIO_CHAN_INFO_SCALE_SEPARATE_BIT,
 559                 .indexed = 1,
 560                 .channel = 0,
 561                 .event_mask =
 562                 IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_RISING)|
 563                 IIO_EV_BIT(IIO_EV_TYPE_THRESH, IIO_EV_DIR_FALLING)
 564         }
 565 };
 566
 567 static struct attribute_group ad7291_event_attribute_group = {
 568         .attrs = ad7291_event_attributes,
 569 };
 570
 571 static const struct iio_info ad7291_info = {
 572         .attrs = &ad7291_attribute_group,
 573         .read_raw = &ad7291_read_raw,
 574         .read_event_config = &ad7291_read_event_config,
 575         .write_event_config = &ad7291_write_event_config,
 576         .read_event_value = &ad7291_read_event_value,
 577         .write_event_value = &ad7291_write_event_value,
 578         .event_attrs = &ad7291_event_attribute_group,
 579 };
 580
 581 static int __devinit ad7291_probe(struct i2c_client *client,
 582                 const struct i2c_device_id *id)
 583 {
 584         struct ad7291_chip_info *chip;
 585         struct iio_dev *indio_dev;
 586         int ret = 0, voltage_uv = 0;
 587
 588         indio_dev = iio_allocate_device(sizeof(*chip));
 589         if (indio_dev == NULL) {
 590                 ret = -ENOMEM;
 591                 goto error_ret;
 592         }
 593         chip = iio_priv(indio_dev);
 594
 595         chip->reg = regulator_get(&client->dev, "vcc");
 596         if (!IS_ERR(chip->reg)) {
 597                 ret = regulator_enable(chip->reg);
 598                 if (ret)
 599                         goto error_put_reg;
 600                 voltage_uv = regulator_get_voltage(chip->reg);
 601         }
 602
 603         mutex_init(&chip->state_lock);
 604         /* this is only used for device removal purposes */
 605         i2c_set_clientdata(client, indio_dev);
 606
 607         chip->client = client;
 608
 609         chip->command = AD7291_NOISE_DELAY |
 610                         AD7291_T_SENSE_MASK | /* Tsense always enabled */
 611                         AD7291_ALERT_POLARITY; /* set irq polarity low level */
 612
 613         if (voltage_uv) {
 614                 chip->int_vref_mv = voltage_uv / 1000;
 615                 chip->command |= AD7291_EXT_REF;
 616         } else {
 617                 chip->int_vref_mv = 2500; /* Build-in ref */
 618         }
 619
 620         indio_dev->name = id->name;
 621         indio_dev->channels = ad7291_channels;
 622         indio_dev->num_channels = ARRAY_SIZE(ad7291_channels);
 623
 624         indio_dev->dev.parent = &client->dev;
 625         indio_dev->info = &ad7291_info;
 626         indio_dev->modes = INDIO_DIRECT_MODE;
 627
 628         ret = ad7291_i2c_write(chip, AD7291_COMMAND, AD7291_RESET);
 629         if (ret) {
 630                 ret = -EIO;
 631                 goto error_disable_reg;
 632         }
 633
 634         ret = ad7291_i2c_write(chip, AD7291_COMMAND, chip->command);
 635         if (ret) {
 636                 ret = -EIO;
 637                 goto error_disable_reg;
 638         }
 639
 640         if (client->irq > 0) {
 641                 ret = request_threaded_irq(client->irq,
 642                                            NULL,
 643                                            &ad7291_event_handler,
 644                                            IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 645                                            id->name,
 646                                            indio_dev);
 647                 if (ret)
 648                         goto error_disable_reg;
 649         }
 650
 651         ret = iio_device_register(indio_dev);
 652         if (ret)
 653                 goto error_unreg_irq;
 654
 655         dev_info(&client->dev, "%s ADC registered.\n",
 656                          id->name);
 657
 658         return 0;
 659
 660 error_unreg_irq:
 661         if (client->irq)
 662                 free_irq(client->irq, indio_dev);
 663 error_disable_reg:
 664         if (!IS_ERR(chip->reg))
 665                 regulator_disable(chip->reg);
 666 error_put_reg:
 667         if (!IS_ERR(chip->reg))
 668                 regulator_put(chip->reg);
 669
 670         iio_free_device(indio_dev);
 671 error_ret:
 672         return ret;
 673 }
 674
 675 static int __devexit ad7291_remove(struct i2c_client *client)
 676 {
 677         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 678         struct ad7291_chip_info *chip = iio_priv(indio_dev);
 679
 680         iio_device_unregister(indio_dev);
 681
 682         if (client->irq)
 683                 free_irq(client->irq, indio_dev);
 684
 685         if (!IS_ERR(chip->reg)) {
 686                 regulator_disable(chip->reg);
 687                 regulator_put(chip->reg);
 688         }
 689
 690         iio_free_device(indio_dev);
 691
 692         return 0;
 693 }
 694
 695 static const struct i2c_device_id ad7291_id[] = {
 696         { "ad7291", 0 },
 697         {}
 698 };
 699
 700 MODULE_DEVICE_TABLE(i2c, ad7291_id);
 701
 702 static struct i2c_driver ad7291_driver = {
 703         .driver = {
 704                 .name = KBUILD_MODNAME,
 705         },
 706         .probe = ad7291_probe,
 707         .remove = __devexit_p(ad7291_remove),
 708         .id_table = ad7291_id,
 709 };
 710 module_i2c_driver(ad7291_driver);
 711
 712 MODULE_AUTHOR("Sonic Zhang <sonic.zhang@analog.com>");
 713 MODULE_DESCRIPTION("Analog Devices AD7291 ADC driver");
 714 MODULE_LICENSE("GPL v2");