drivers/iio/adc/axp20x_adc.c

   1 /* ADC driver for AXP20X and AXP22X PMICs
   2  *
   3  * Copyright (c) 2016 Free Electrons NextThing Co.
   4  *      Quentin Schulz <quentin.schulz@free-electrons.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it under
   7  * the terms of the GNU General Public License version 2 as published by the
   8  * Free Software Foundation.
   9  */
  10
  11 #include <linux/completion.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/io.h>
  14 #include <linux/module.h>
  15 #include <linux/of.h>
  16 #include <linux/of_device.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/pm_runtime.h>
  19 #include <linux/regmap.h>
  20 #include <linux/thermal.h>
  21
  22 #include <linux/iio/iio.h>
  23 #include <linux/iio/driver.h>
  24 #include <linux/iio/machine.h>
  25 #include <linux/mfd/axp20x.h>
  26
  27 #define AXP20X_ADC_EN1_MASK                     GENMASK(7, 0)
  28
  29 #define AXP20X_ADC_EN2_MASK                     (GENMASK(3, 2) | BIT(7))
  30 #define AXP22X_ADC_EN1_MASK                     (GENMASK(7, 5) | BIT(0))
  31
  32 #define AXP20X_GPIO10_IN_RANGE_GPIO0            BIT(0)
  33 #define AXP20X_GPIO10_IN_RANGE_GPIO1            BIT(1)
  34 #define AXP20X_GPIO10_IN_RANGE_GPIO0_VAL(x)     ((x) & BIT(0))
  35 #define AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(x)     (((x) & BIT(0)) << 1)
  36
  37 #define AXP20X_ADC_RATE_MASK                    GENMASK(7, 6)
  38 #define AXP20X_ADC_RATE_HZ(x)                   ((ilog2((x) / 25) << 6) & AXP20X_ADC_RATE_MASK)
  39 #define AXP22X_ADC_RATE_HZ(x)                   ((ilog2((x) / 100) << 6) & AXP20X_ADC_RATE_MASK)
  40
  41 #define AXP20X_ADC_CHANNEL(_channel, _name, _type, _reg)        \
  42         {                                                       \
  43                 .type = _type,                                  \
  44                 .indexed = 1,                                   \
  45                 .channel = _channel,                            \
  46                 .address = _reg,                                \
  47                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
  48                                       BIT(IIO_CHAN_INFO_SCALE), \
  49                 .datasheet_name = _name,                        \
  50         }
  51
  52 #define AXP20X_ADC_CHANNEL_OFFSET(_channel, _name, _type, _reg) \
  53         {                                                       \
  54                 .type = _type,                                  \
  55                 .indexed = 1,                                   \
  56                 .channel = _channel,                            \
  57                 .address = _reg,                                \
  58                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
  59                                       BIT(IIO_CHAN_INFO_SCALE) |\
  60                                       BIT(IIO_CHAN_INFO_OFFSET),\
  61                 .datasheet_name = _name,                        \
  62         }
  63
  64 struct axp_data;
  65
  66 struct axp20x_adc_iio {
  67         struct regmap           *regmap;
  68         struct axp_data         *data;
  69 };
  70
  71 enum axp20x_adc_channel_v {
  72         AXP20X_ACIN_V = 0,
  73         AXP20X_VBUS_V,
  74         AXP20X_TS_IN,
  75         AXP20X_GPIO0_V,
  76         AXP20X_GPIO1_V,
  77         AXP20X_IPSOUT_V,
  78         AXP20X_BATT_V,
  79 };
  80
  81 enum axp20x_adc_channel_i {
  82         AXP20X_ACIN_I = 0,
  83         AXP20X_VBUS_I,
  84         AXP20X_BATT_CHRG_I,
  85         AXP20X_BATT_DISCHRG_I,
  86 };
  87
  88 enum axp22x_adc_channel_v {
  89         AXP22X_TS_IN = 0,
  90         AXP22X_BATT_V,
  91 };
  92
  93 enum axp22x_adc_channel_i {
  94         AXP22X_BATT_CHRG_I = 1,
  95         AXP22X_BATT_DISCHRG_I,
  96 };
  97
  98 static struct iio_map axp20x_maps[] = {
  99         {
 100                 .consumer_dev_name = "axp20x-usb-power-supply",
 101                 .consumer_channel = "vbus_v",
 102                 .adc_channel_label = "vbus_v",
 103         }, {
 104                 .consumer_dev_name = "axp20x-usb-power-supply",
 105                 .consumer_channel = "vbus_i",
 106                 .adc_channel_label = "vbus_i",
 107         }, {
 108                 .consumer_dev_name = "axp20x-ac-power-supply",
 109                 .consumer_channel = "acin_v",
 110                 .adc_channel_label = "acin_v",
 111         }, {
 112                 .consumer_dev_name = "axp20x-ac-power-supply",
 113                 .consumer_channel = "acin_i",
 114                 .adc_channel_label = "acin_i",
 115         }, {
 116                 .consumer_dev_name = "axp20x-battery-power-supply",
 117                 .consumer_channel = "batt_v",
 118                 .adc_channel_label = "batt_v",
 119         }, {
 120                 .consumer_dev_name = "axp20x-battery-power-supply",
 121                 .consumer_channel = "batt_chrg_i",
 122                 .adc_channel_label = "batt_chrg_i",
 123         }, {
 124                 .consumer_dev_name = "axp20x-battery-power-supply",
 125                 .consumer_channel = "batt_dischrg_i",
 126                 .adc_channel_label = "batt_dischrg_i",
 127         }, { /* sentinel */ }
 128 };
 129
 130 static struct iio_map axp22x_maps[] = {
 131         {
 132                 .consumer_dev_name = "axp20x-battery-power-supply",
 133                 .consumer_channel = "batt_v",
 134                 .adc_channel_label = "batt_v",
 135         }, {
 136                 .consumer_dev_name = "axp20x-battery-power-supply",
 137                 .consumer_channel = "batt_chrg_i",
 138                 .adc_channel_label = "batt_chrg_i",
 139         }, {
 140                 .consumer_dev_name = "axp20x-battery-power-supply",
 141                 .consumer_channel = "batt_dischrg_i",
 142                 .adc_channel_label = "batt_dischrg_i",
 143         }, { /* sentinel */ }
 144 };
 145
 146 /*
 147  * Channels are mapped by physical system. Their channels share the same index.
 148  * i.e. acin_i is in_current0_raw and acin_v is in_voltage0_raw.
 149  * The only exception is for the battery. batt_v will be in_voltage6_raw and
 150  * charge current in_current6_raw and discharge current will be in_current7_raw.
 151  */
 152 static const struct iio_chan_spec axp20x_adc_channels[] = {
 153         AXP20X_ADC_CHANNEL(AXP20X_ACIN_V, "acin_v", IIO_VOLTAGE,
 154                            AXP20X_ACIN_V_ADC_H),
 155         AXP20X_ADC_CHANNEL(AXP20X_ACIN_I, "acin_i", IIO_CURRENT,
 156                            AXP20X_ACIN_I_ADC_H),
 157         AXP20X_ADC_CHANNEL(AXP20X_VBUS_V, "vbus_v", IIO_VOLTAGE,
 158                            AXP20X_VBUS_V_ADC_H),
 159         AXP20X_ADC_CHANNEL(AXP20X_VBUS_I, "vbus_i", IIO_CURRENT,
 160                            AXP20X_VBUS_I_ADC_H),
 161         {
 162                 .type = IIO_TEMP,
 163                 .address = AXP20X_TEMP_ADC_H,
 164                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 165                                       BIT(IIO_CHAN_INFO_SCALE) |
 166                                       BIT(IIO_CHAN_INFO_OFFSET),
 167                 .datasheet_name = "pmic_temp",
 168         },
 169         AXP20X_ADC_CHANNEL_OFFSET(AXP20X_GPIO0_V, "gpio0_v", IIO_VOLTAGE,
 170                                   AXP20X_GPIO0_V_ADC_H),
 171         AXP20X_ADC_CHANNEL_OFFSET(AXP20X_GPIO1_V, "gpio1_v", IIO_VOLTAGE,
 172                                   AXP20X_GPIO1_V_ADC_H),
 173         AXP20X_ADC_CHANNEL(AXP20X_IPSOUT_V, "ipsout_v", IIO_VOLTAGE,
 174                            AXP20X_IPSOUT_V_HIGH_H),
 175         AXP20X_ADC_CHANNEL(AXP20X_BATT_V, "batt_v", IIO_VOLTAGE,
 176                            AXP20X_BATT_V_H),
 177         AXP20X_ADC_CHANNEL(AXP20X_BATT_CHRG_I, "batt_chrg_i", IIO_CURRENT,
 178                            AXP20X_BATT_CHRG_I_H),
 179         AXP20X_ADC_CHANNEL(AXP20X_BATT_DISCHRG_I, "batt_dischrg_i", IIO_CURRENT,
 180                            AXP20X_BATT_DISCHRG_I_H),
 181 };
 182
 183 static const struct iio_chan_spec axp22x_adc_channels[] = {
 184         {
 185                 .type = IIO_TEMP,
 186                 .address = AXP22X_PMIC_TEMP_H,
 187                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 188                                       BIT(IIO_CHAN_INFO_SCALE) |
 189                                       BIT(IIO_CHAN_INFO_OFFSET),
 190                 .datasheet_name = "pmic_temp",
 191         },
 192         AXP20X_ADC_CHANNEL(AXP22X_BATT_V, "batt_v", IIO_VOLTAGE,
 193                            AXP20X_BATT_V_H),
 194         AXP20X_ADC_CHANNEL(AXP22X_BATT_CHRG_I, "batt_chrg_i", IIO_CURRENT,
 195                            AXP20X_BATT_CHRG_I_H),
 196         AXP20X_ADC_CHANNEL(AXP22X_BATT_DISCHRG_I, "batt_dischrg_i", IIO_CURRENT,
 197                            AXP20X_BATT_DISCHRG_I_H),
 198 };
 199
 200 static int axp20x_adc_raw(struct iio_dev *indio_dev,
 201                           struct iio_chan_spec const *chan, int *val)
 202 {
 203         struct axp20x_adc_iio *info = iio_priv(indio_dev);
 204         int size = 12;
 205
 206         /*
 207          * N.B.:  Unlike the Chinese datasheets tell, the charging current is
 208          * stored on 12 bits, not 13 bits. Only discharging current is on 13
 209          * bits.
 210          */
 211         if (chan->type == IIO_CURRENT && chan->channel == AXP20X_BATT_DISCHRG_I)
 212                 size = 13;
 213         else
 214                 size = 12;
 215
 216         *val = axp20x_read_variable_width(info->regmap, chan->address, size);
 217         if (*val < 0)
 218                 return *val;
 219
 220         return IIO_VAL_INT;
 221 }
 222
 223 static int axp22x_adc_raw(struct iio_dev *indio_dev,
 224                           struct iio_chan_spec const *chan, int *val)
 225 {
 226         struct axp20x_adc_iio *info = iio_priv(indio_dev);
 227
 228         *val = axp20x_read_variable_width(info->regmap, chan->address, 12);
 229         if (*val < 0)
 230                 return *val;
 231
 232         return IIO_VAL_INT;
 233 }
 234
 235 static int axp20x_adc_scale_voltage(int channel, int *val, int *val2)
 236 {
 237         switch (channel) {
 238         case AXP20X_ACIN_V:
 239         case AXP20X_VBUS_V:
 240                 *val = 1;
 241                 *val2 = 700000;
 242                 return IIO_VAL_INT_PLUS_MICRO;
 243
 244         case AXP20X_GPIO0_V:
 245         case AXP20X_GPIO1_V:
 246                 *val = 0;
 247                 *val2 = 500000;
 248                 return IIO_VAL_INT_PLUS_MICRO;
 249
 250         case AXP20X_BATT_V:
 251                 *val = 1;
 252                 *val2 = 100000;
 253                 return IIO_VAL_INT_PLUS_MICRO;
 254
 255         case AXP20X_IPSOUT_V:
 256                 *val = 1;
 257                 *val2 = 400000;
 258                 return IIO_VAL_INT_PLUS_MICRO;
 259
 260         default:
 261                 return -EINVAL;
 262         }
 263 }
 264
 265 static int axp20x_adc_scale_current(int channel, int *val, int *val2)
 266 {
 267         switch (channel) {
 268         case AXP20X_ACIN_I:
 269                 *val = 0;
 270                 *val2 = 625000;
 271                 return IIO_VAL_INT_PLUS_MICRO;
 272
 273         case AXP20X_VBUS_I:
 274                 *val = 0;
 275                 *val2 = 375000;
 276                 return IIO_VAL_INT_PLUS_MICRO;
 277
 278         case AXP20X_BATT_DISCHRG_I:
 279         case AXP20X_BATT_CHRG_I:
 280                 *val = 0;
 281                 *val2 = 500000;
 282                 return IIO_VAL_INT_PLUS_MICRO;
 283
 284         default:
 285                 return -EINVAL;
 286         }
 287 }
 288
 289 static int axp20x_adc_scale(struct iio_chan_spec const *chan, int *val,
 290                             int *val2)
 291 {
 292         switch (chan->type) {
 293         case IIO_VOLTAGE:
 294                 return axp20x_adc_scale_voltage(chan->channel, val, val2);
 295
 296         case IIO_CURRENT:
 297                 return axp20x_adc_scale_current(chan->channel, val, val2);
 298
 299         case IIO_TEMP:
 300                 *val = 100;
 301                 return IIO_VAL_INT;
 302
 303         default:
 304                 return -EINVAL;
 305         }
 306 }
 307
 308 static int axp22x_adc_scale(struct iio_chan_spec const *chan, int *val,
 309                             int *val2)
 310 {
 311         switch (chan->type) {
 312         case IIO_VOLTAGE:
 313                 if (chan->channel != AXP22X_BATT_V)
 314                         return -EINVAL;
 315
 316                 *val = 1;
 317                 *val2 = 100000;
 318                 return IIO_VAL_INT_PLUS_MICRO;
 319
 320         case IIO_CURRENT:
 321                 *val = 1;
 322                 return IIO_VAL_INT;
 323
 324         case IIO_TEMP:
 325                 *val = 100;
 326                 return IIO_VAL_INT;
 327
 328         default:
 329                 return -EINVAL;
 330         }
 331 }
 332
 333 static int axp20x_adc_offset_voltage(struct iio_dev *indio_dev, int channel,
 334                                      int *val)
 335 {
 336         struct axp20x_adc_iio *info = iio_priv(indio_dev);
 337         int ret;
 338
 339         ret = regmap_read(info->regmap, AXP20X_GPIO10_IN_RANGE, val);
 340         if (ret < 0)
 341                 return ret;
 342
 343         switch (channel) {
 344         case AXP20X_GPIO0_V:
 345                 *val &= AXP20X_GPIO10_IN_RANGE_GPIO0;
 346                 break;
 347
 348         case AXP20X_GPIO1_V:
 349                 *val &= AXP20X_GPIO10_IN_RANGE_GPIO1;
 350                 break;
 351
 352         default:
 353                 return -EINVAL;
 354         }
 355
 356         *val = !!(*val) * 700000;
 357
 358         return IIO_VAL_INT;
 359 }
 360
 361 static int axp20x_adc_offset(struct iio_dev *indio_dev,
 362                              struct iio_chan_spec const *chan, int *val)
 363 {
 364         switch (chan->type) {
 365         case IIO_VOLTAGE:
 366                 return axp20x_adc_offset_voltage(indio_dev, chan->channel, val);
 367
 368         case IIO_TEMP:
 369                 *val = -1447;
 370                 return IIO_VAL_INT;
 371
 372         default:
 373                 return -EINVAL;
 374         }
 375 }
 376
 377 static int axp20x_read_raw(struct iio_dev *indio_dev,
 378                            struct iio_chan_spec const *chan, int *val,
 379                            int *val2, long mask)
 380 {
 381         switch (mask) {
 382         case IIO_CHAN_INFO_OFFSET:
 383                 return axp20x_adc_offset(indio_dev, chan, val);
 384
 385         case IIO_CHAN_INFO_SCALE:
 386                 return axp20x_adc_scale(chan, val, val2);
 387
 388         case IIO_CHAN_INFO_RAW:
 389                 return axp20x_adc_raw(indio_dev, chan, val);
 390
 391         default:
 392                 return -EINVAL;
 393         }
 394 }
 395
 396 static int axp22x_read_raw(struct iio_dev *indio_dev,
 397                            struct iio_chan_spec const *chan, int *val,
 398                            int *val2, long mask)
 399 {
 400         switch (mask) {
 401         case IIO_CHAN_INFO_OFFSET:
 402                 *val = -2677;
 403                 return IIO_VAL_INT;
 404
 405         case IIO_CHAN_INFO_SCALE:
 406                 return axp22x_adc_scale(chan, val, val2);
 407
 408         case IIO_CHAN_INFO_RAW:
 409                 return axp22x_adc_raw(indio_dev, chan, val);
 410
 411         default:
 412                 return -EINVAL;
 413         }
 414 }
 415
 416 static int axp20x_write_raw(struct iio_dev *indio_dev,
 417                             struct iio_chan_spec const *chan, int val, int val2,
 418                             long mask)
 419 {
 420         struct axp20x_adc_iio *info = iio_priv(indio_dev);
 421         unsigned int reg, regval;
 422
 423         /*
 424          * The AXP20X PMIC allows the user to choose between 0V and 0.7V offsets
 425          * for (independently) GPIO0 and GPIO1 when in ADC mode.
 426          */
 427         if (mask != IIO_CHAN_INFO_OFFSET)
 428                 return -EINVAL;
 429
 430         if (val != 0 && val != 700000)
 431                 return -EINVAL;
 432
 433         switch (chan->channel) {
 434         case AXP20X_GPIO0_V:
 435                 reg = AXP20X_GPIO10_IN_RANGE_GPIO0;
 436                 regval = AXP20X_GPIO10_IN_RANGE_GPIO0_VAL(!!val);
 437                 break;
 438
 439         case AXP20X_GPIO1_V:
 440                 reg = AXP20X_GPIO10_IN_RANGE_GPIO1;
 441                 regval = AXP20X_GPIO10_IN_RANGE_GPIO1_VAL(!!val);
 442                 break;
 443
 444         default:
 445                 return -EINVAL;
 446         }
 447
 448         return regmap_update_bits(info->regmap, AXP20X_GPIO10_IN_RANGE, reg,
 449                                   regval);
 450 }
 451
 452 static const struct iio_info axp20x_adc_iio_info = {
 453         .read_raw = axp20x_read_raw,
 454         .write_raw = axp20x_write_raw,
 455         .driver_module = THIS_MODULE,
 456 };
 457
 458 static const struct iio_info axp22x_adc_iio_info = {
 459         .read_raw = axp22x_read_raw,
 460         .driver_module = THIS_MODULE,
 461 };
 462
 463 static int axp20x_adc_rate(int rate)
 464 {
 465         return AXP20X_ADC_RATE_HZ(rate);
 466 }
 467
 468 static int axp22x_adc_rate(int rate)
 469 {
 470         return AXP22X_ADC_RATE_HZ(rate);
 471 }
 472
 473 struct axp_data {
 474         const struct iio_info           *iio_info;
 475         int                             num_channels;
 476         struct iio_chan_spec const      *channels;
 477         unsigned long                   adc_en1_mask;
 478         int                             (*adc_rate)(int rate);
 479         bool                            adc_en2;
 480         struct iio_map                  *maps;
 481 };
 482
 483 static const struct axp_data axp20x_data = {
 484         .iio_info = &axp20x_adc_iio_info,
 485         .num_channels = ARRAY_SIZE(axp20x_adc_channels),
 486         .channels = axp20x_adc_channels,
 487         .adc_en1_mask = AXP20X_ADC_EN1_MASK,
 488         .adc_rate = axp20x_adc_rate,
 489         .adc_en2 = true,
 490         .maps = axp20x_maps,
 491 };
 492
 493 static const struct axp_data axp22x_data = {
 494         .iio_info = &axp22x_adc_iio_info,
 495         .num_channels = ARRAY_SIZE(axp22x_adc_channels),
 496         .channels = axp22x_adc_channels,
 497         .adc_en1_mask = AXP22X_ADC_EN1_MASK,
 498         .adc_rate = axp22x_adc_rate,
 499         .adc_en2 = false,
 500         .maps = axp22x_maps,
 501 };
 502
 503 static const struct platform_device_id axp20x_adc_id_match[] = {
 504         { .name = "axp20x-adc", .driver_data = (kernel_ulong_t)&axp20x_data, },
 505         { .name = "axp22x-adc", .driver_data = (kernel_ulong_t)&axp22x_data, },
 506         { /* sentinel */ },
 507 };
 508 MODULE_DEVICE_TABLE(platform, axp20x_adc_id_match);
 509
 510 static int axp20x_probe(struct platform_device *pdev)
 511 {
 512         struct axp20x_adc_iio *info;
 513         struct iio_dev *indio_dev;
 514         struct axp20x_dev *axp20x_dev;
 515         int ret;
 516
 517         axp20x_dev = dev_get_drvdata(pdev->dev.parent);
 518
 519         indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*info));
 520         if (!indio_dev)
 521                 return -ENOMEM;
 522
 523         info = iio_priv(indio_dev);
 524         platform_set_drvdata(pdev, indio_dev);
 525
 526         info->regmap = axp20x_dev->regmap;
 527         indio_dev->dev.parent = &pdev->dev;
 528         indio_dev->dev.of_node = pdev->dev.of_node;
 529         indio_dev->modes = INDIO_DIRECT_MODE;
 530
 531         info->data = (struct axp_data *)platform_get_device_id(pdev)->driver_data;
 532
 533         indio_dev->name = platform_get_device_id(pdev)->name;
 534         indio_dev->info = info->data->iio_info;
 535         indio_dev->num_channels = info->data->num_channels;
 536         indio_dev->channels = info->data->channels;
 537
 538         /* Enable the ADCs on IP */
 539         regmap_write(info->regmap, AXP20X_ADC_EN1, info->data->adc_en1_mask);
 540
 541         if (info->data->adc_en2)
 542                 /* Enable GPIO0/1 and internal temperature ADCs */
 543                 regmap_update_bits(info->regmap, AXP20X_ADC_EN2,
 544                                    AXP20X_ADC_EN2_MASK, AXP20X_ADC_EN2_MASK);
 545
 546         /* Configure ADCs rate */
 547         regmap_update_bits(info->regmap, AXP20X_ADC_RATE, AXP20X_ADC_RATE_MASK,
 548                            info->data->adc_rate(100));
 549
 550         ret = iio_map_array_register(indio_dev, info->data->maps);
 551         if (ret < 0) {
 552                 dev_err(&pdev->dev, "failed to register IIO maps: %d\n", ret);
 553                 goto fail_map;
 554         }
 555
 556         ret = iio_device_register(indio_dev);
 557         if (ret < 0) {
 558                 dev_err(&pdev->dev, "could not register the device\n");
 559                 goto fail_register;
 560         }
 561
 562         return 0;
 563
 564 fail_register:
 565         iio_map_array_unregister(indio_dev);
 566
 567 fail_map:
 568         regmap_write(info->regmap, AXP20X_ADC_EN1, 0);
 569
 570         if (info->data->adc_en2)
 571                 regmap_write(info->regmap, AXP20X_ADC_EN2, 0);
 572
 573         return ret;
 574 }
 575
 576 static int axp20x_remove(struct platform_device *pdev)
 577 {
 578         struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 579         struct axp20x_adc_iio *info = iio_priv(indio_dev);
 580
 581         iio_device_unregister(indio_dev);
 582         iio_map_array_unregister(indio_dev);
 583
 584         regmap_write(info->regmap, AXP20X_ADC_EN1, 0);
 585
 586         if (info->data->adc_en2)
 587                 regmap_write(info->regmap, AXP20X_ADC_EN2, 0);
 588
 589         return 0;
 590 }
 591
 592 static struct platform_driver axp20x_adc_driver = {
 593         .driver = {
 594                 .name = "axp20x-adc",
 595         },
 596         .id_table = axp20x_adc_id_match,
 597         .probe = axp20x_probe,
 598         .remove = axp20x_remove,
 599 };
 600
 601 module_platform_driver(axp20x_adc_driver);
 602
 603 MODULE_DESCRIPTION("ADC driver for AXP20X and AXP22X PMICs");
 604 MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
 605 MODULE_LICENSE("GPL");