drivers/iio/adc/palmas_gpadc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * palmas-adc.c -- TI PALMAS GPADC.
   4  *
   5  * Copyright (c) 2013, NVIDIA Corporation. All rights reserved.
   6  *
   7  * Author: Pradeep Goudagunta <pgoudagunta@nvidia.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/err.h>
  12 #include <linux/irq.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/slab.h>
  16 #include <linux/delay.h>
  17 #include <linux/pm.h>
  18 #include <linux/mfd/palmas.h>
  19 #include <linux/completion.h>
  20 #include <linux/of.h>
  21 #include <linux/iio/events.h>
  22 #include <linux/iio/iio.h>
  23 #include <linux/iio/machine.h>
  24 #include <linux/iio/driver.h>
  25
  26 #define MOD_NAME "palmas-gpadc"
  27 #define PALMAS_ADC_CONVERSION_TIMEOUT   (msecs_to_jiffies(5000))
  28 #define PALMAS_TO_BE_CALCULATED 0
  29 #define PALMAS_GPADC_TRIMINVALID        -1
  30
  31 struct palmas_gpadc_info {
  32 /* calibration codes and regs */
  33         int x1; /* lower ideal code */
  34         int x2; /* higher ideal code */
  35         int v1; /* expected lower volt reading */
  36         int v2; /* expected higher volt reading */
  37         u8 trim1_reg;   /* register number for lower trim */
  38         u8 trim2_reg;   /* register number for upper trim */
  39         int gain;       /* calculated from above (after reading trim regs) */
  40         int offset;     /* calculated from above (after reading trim regs) */
  41         int gain_error; /* calculated from above (after reading trim regs) */
  42         bool is_uncalibrated;   /* if channel has calibration data */
  43 };
  44
  45 #define PALMAS_ADC_INFO(_chan, _x1, _x2, _v1, _v2, _t1, _t2, _is_uncalibrated) \
  46         [PALMAS_ADC_CH_##_chan] = { \
  47                 .x1 = _x1, \
  48                 .x2 = _x2, \
  49                 .v1 = _v1, \
  50                 .v2 = _v2, \
  51                 .gain = PALMAS_TO_BE_CALCULATED, \
  52                 .offset = PALMAS_TO_BE_CALCULATED, \
  53                 .gain_error = PALMAS_TO_BE_CALCULATED, \
  54                 .trim1_reg = PALMAS_GPADC_TRIM##_t1, \
  55                 .trim2_reg = PALMAS_GPADC_TRIM##_t2,  \
  56                 .is_uncalibrated = _is_uncalibrated \
  57         }
  58
  59 static struct palmas_gpadc_info palmas_gpadc_info[] = {
  60         PALMAS_ADC_INFO(IN0, 2064, 3112, 630, 950, 1, 2, false),
  61         PALMAS_ADC_INFO(IN1, 2064, 3112, 630, 950, 1, 2, false),
  62         PALMAS_ADC_INFO(IN2, 2064, 3112, 1260, 1900, 3, 4, false),
  63         PALMAS_ADC_INFO(IN3, 2064, 3112, 630, 950, 1, 2, false),
  64         PALMAS_ADC_INFO(IN4, 2064, 3112, 630, 950, 1, 2, false),
  65         PALMAS_ADC_INFO(IN5, 2064, 3112, 630, 950, 1, 2, false),
  66         PALMAS_ADC_INFO(IN6, 2064, 3112, 2520, 3800, 5, 6, false),
  67         PALMAS_ADC_INFO(IN7, 2064, 3112, 2520, 3800, 7, 8, false),
  68         PALMAS_ADC_INFO(IN8, 2064, 3112, 3150, 4750, 9, 10, false),
  69         PALMAS_ADC_INFO(IN9, 2064, 3112, 5670, 8550, 11, 12, false),
  70         PALMAS_ADC_INFO(IN10, 2064, 3112, 3465, 5225, 13, 14, false),
  71         PALMAS_ADC_INFO(IN11, 0, 0, 0, 0, INVALID, INVALID, true),
  72         PALMAS_ADC_INFO(IN12, 0, 0, 0, 0, INVALID, INVALID, true),
  73         PALMAS_ADC_INFO(IN13, 0, 0, 0, 0, INVALID, INVALID, true),
  74         PALMAS_ADC_INFO(IN14, 2064, 3112, 3645, 5225, 15, 16, false),
  75         PALMAS_ADC_INFO(IN15, 0, 0, 0, 0, INVALID, INVALID, true),
  76 };
  77
  78 struct palmas_adc_event {
  79         bool enabled;
  80         int channel;
  81         enum iio_event_direction direction;
  82 };
  83
  84 struct palmas_gpadc_thresholds {
  85         int high;
  86         int low;
  87 };
  88
  89 /*
  90  * struct palmas_gpadc - the palmas_gpadc structure
  91  * @ch0_current:        channel 0 current source setting
  92  *                      0: 0 uA
  93  *                      1: 5 uA
  94  *                      2: 15 uA
  95  *                      3: 20 uA
  96  * @ch3_current:        channel 0 current source setting
  97  *                      0: 0 uA
  98  *                      1: 10 uA
  99  *                      2: 400 uA
 100  *                      3: 800 uA
 101  * @extended_delay:     enable the gpadc extended delay mode
 102  * @auto_conversion_period:     define the auto_conversion_period
 103  * @lock:       Lock to protect the device state during a potential concurrent
 104  *              read access from userspace. Reading a raw value requires a sequence
 105  *              of register writes, then a wait for a completion callback,
 106  *              and finally a register read, during which userspace could issue
 107  *              another read request. This lock protects a read access from
 108  *              ocurring before another one has finished.
 109  *
 110  * This is the palmas_gpadc structure to store run-time information
 111  * and pointers for this driver instance.
 112  */
 113 struct palmas_gpadc {
 114         struct device                   *dev;
 115         struct palmas                   *palmas;
 116         u8                              ch0_current;
 117         u8                              ch3_current;
 118         bool                            extended_delay;
 119         int                             irq;
 120         int                             irq_auto_0;
 121         int                             irq_auto_1;
 122         struct palmas_gpadc_info        *adc_info;
 123         struct completion               conv_completion;
 124         struct palmas_adc_event         event0;
 125         struct palmas_adc_event         event1;
 126         struct palmas_gpadc_thresholds  thresholds[PALMAS_ADC_CH_MAX];
 127         int                             auto_conversion_period;
 128         struct mutex                    lock;
 129 };
 130
 131 static struct palmas_adc_event *palmas_gpadc_get_event(struct palmas_gpadc *adc,
 132                                                        int adc_chan,
 133                                                        enum iio_event_direction dir)
 134 {
 135         if (adc_chan == adc->event0.channel && dir == adc->event0.direction)
 136                 return &adc->event0;
 137
 138         if (adc_chan == adc->event1.channel && dir == adc->event1.direction)
 139                 return &adc->event1;
 140
 141         return NULL;
 142 }
 143
 144 static bool palmas_gpadc_channel_is_freerunning(struct palmas_gpadc *adc,
 145                                                 int adc_chan)
 146 {
 147         return palmas_gpadc_get_event(adc, adc_chan, IIO_EV_DIR_RISING) ||
 148                 palmas_gpadc_get_event(adc, adc_chan, IIO_EV_DIR_FALLING);
 149 }
 150
 151 /*
 152  * GPADC lock issue in AUTO mode.
 153  * Impact: In AUTO mode, GPADC conversion can be locked after disabling AUTO
 154  *         mode feature.
 155  * Details:
 156  *      When the AUTO mode is the only conversion mode enabled, if the AUTO
 157  *      mode feature is disabled with bit GPADC_AUTO_CTRL.  AUTO_CONV1_EN = 0
 158  *      or bit GPADC_AUTO_CTRL.  AUTO_CONV0_EN = 0 during a conversion, the
 159  *      conversion mechanism can be seen as locked meaning that all following
 160  *      conversion will give 0 as a result.  Bit GPADC_STATUS.GPADC_AVAILABLE
 161  *      will stay at 0 meaning that GPADC is busy.  An RT conversion can unlock
 162  *      the GPADC.
 163  *
 164  * Workaround(s):
 165  *      To avoid the lock mechanism, the workaround to follow before any stop
 166  *      conversion request is:
 167  *      Force the GPADC state machine to be ON by using the GPADC_CTRL1.
 168  *              GPADC_FORCE bit = 1
 169  *      Shutdown the GPADC AUTO conversion using
 170  *              GPADC_AUTO_CTRL.SHUTDOWN_CONV[01] = 0.
 171  *      After 100us, force the GPADC state machine to be OFF by using the
 172  *              GPADC_CTRL1.  GPADC_FORCE bit = 0
 173  */
 174
 175 static int palmas_disable_auto_conversion(struct palmas_gpadc *adc)
 176 {
 177         int ret;
 178
 179         ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 180                         PALMAS_GPADC_CTRL1,
 181                         PALMAS_GPADC_CTRL1_GPADC_FORCE,
 182                         PALMAS_GPADC_CTRL1_GPADC_FORCE);
 183         if (ret < 0) {
 184                 dev_err(adc->dev, "GPADC_CTRL1 update failed: %d\n", ret);
 185                 return ret;
 186         }
 187
 188         ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 189                         PALMAS_GPADC_AUTO_CTRL,
 190                         PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV1 |
 191                         PALMAS_GPADC_AUTO_CTRL_SHUTDOWN_CONV0,
 192                         0);
 193         if (ret < 0) {
 194                 dev_err(adc->dev, "AUTO_CTRL update failed: %d\n", ret);
 195                 return ret;
 196         }
 197
 198         udelay(100);
 199
 200         ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 201                         PALMAS_GPADC_CTRL1,
 202                         PALMAS_GPADC_CTRL1_GPADC_FORCE, 0);
 203         if (ret < 0)
 204                 dev_err(adc->dev, "GPADC_CTRL1 update failed: %d\n", ret);
 205
 206         return ret;
 207 }
 208
 209 static irqreturn_t palmas_gpadc_irq(int irq, void *data)
 210 {
 211         struct palmas_gpadc *adc = data;
 212
 213         complete(&adc->conv_completion);
 214
 215         return IRQ_HANDLED;
 216 }
 217
 218 static irqreturn_t palmas_gpadc_irq_auto(int irq, void *data)
 219 {
 220         struct iio_dev *indio_dev = data;
 221         struct palmas_gpadc *adc = iio_priv(indio_dev);
 222         struct palmas_adc_event *ev;
 223
 224         dev_dbg(adc->dev, "Threshold interrupt %d occurs\n", irq);
 225         palmas_disable_auto_conversion(adc);
 226
 227         ev = (irq == adc->irq_auto_0) ? &adc->event0 : &adc->event1;
 228         if (ev->channel != -1) {
 229                 enum iio_event_direction dir;
 230                 u64 code;
 231
 232                 dir = ev->direction;
 233                 code = IIO_UNMOD_EVENT_CODE(IIO_VOLTAGE, ev->channel,
 234                                             IIO_EV_TYPE_THRESH, dir);
 235                 iio_push_event(indio_dev, code, iio_get_time_ns(indio_dev));
 236         }
 237
 238         return IRQ_HANDLED;
 239 }
 240
 241 static int palmas_gpadc_start_mask_interrupt(struct palmas_gpadc *adc,
 242                                                 bool mask)
 243 {
 244         int ret;
 245
 246         if (!mask)
 247                 ret = palmas_update_bits(adc->palmas, PALMAS_INTERRUPT_BASE,
 248                                         PALMAS_INT3_MASK,
 249                                         PALMAS_INT3_MASK_GPADC_EOC_SW, 0);
 250         else
 251                 ret = palmas_update_bits(adc->palmas, PALMAS_INTERRUPT_BASE,
 252                                         PALMAS_INT3_MASK,
 253                                         PALMAS_INT3_MASK_GPADC_EOC_SW,
 254                                         PALMAS_INT3_MASK_GPADC_EOC_SW);
 255         if (ret < 0)
 256                 dev_err(adc->dev, "GPADC INT MASK update failed: %d\n", ret);
 257
 258         return ret;
 259 }
 260
 261 static int palmas_gpadc_enable(struct palmas_gpadc *adc, int adc_chan,
 262                                int enable)
 263 {
 264         unsigned int mask, val;
 265         int ret;
 266
 267         if (enable) {
 268                 val = (adc->extended_delay
 269                         << PALMAS_GPADC_RT_CTRL_EXTEND_DELAY_SHIFT);
 270                 ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 271                                         PALMAS_GPADC_RT_CTRL,
 272                                         PALMAS_GPADC_RT_CTRL_EXTEND_DELAY, val);
 273                 if (ret < 0) {
 274                         dev_err(adc->dev, "RT_CTRL update failed: %d\n", ret);
 275                         return ret;
 276                 }
 277
 278                 mask = (PALMAS_GPADC_CTRL1_CURRENT_SRC_CH0_MASK |
 279                         PALMAS_GPADC_CTRL1_CURRENT_SRC_CH3_MASK |
 280                         PALMAS_GPADC_CTRL1_GPADC_FORCE);
 281                 val = (adc->ch0_current
 282                         << PALMAS_GPADC_CTRL1_CURRENT_SRC_CH0_SHIFT);
 283                 val |= (adc->ch3_current
 284                         << PALMAS_GPADC_CTRL1_CURRENT_SRC_CH3_SHIFT);
 285                 val |= PALMAS_GPADC_CTRL1_GPADC_FORCE;
 286                 ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 287                                 PALMAS_GPADC_CTRL1, mask, val);
 288                 if (ret < 0) {
 289                         dev_err(adc->dev,
 290                                 "Failed to update current setting: %d\n", ret);
 291                         return ret;
 292                 }
 293
 294                 mask = (PALMAS_GPADC_SW_SELECT_SW_CONV0_SEL_MASK |
 295                         PALMAS_GPADC_SW_SELECT_SW_CONV_EN);
 296                 val = (adc_chan | PALMAS_GPADC_SW_SELECT_SW_CONV_EN);
 297                 ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 298                                 PALMAS_GPADC_SW_SELECT, mask, val);
 299                 if (ret < 0) {
 300                         dev_err(adc->dev, "SW_SELECT update failed: %d\n", ret);
 301                         return ret;
 302                 }
 303         } else {
 304                 ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
 305                                 PALMAS_GPADC_SW_SELECT, 0);
 306                 if (ret < 0)
 307                         dev_err(adc->dev, "SW_SELECT write failed: %d\n", ret);
 308
 309                 ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 310                                 PALMAS_GPADC_CTRL1,
 311                                 PALMAS_GPADC_CTRL1_GPADC_FORCE, 0);
 312                 if (ret < 0) {
 313                         dev_err(adc->dev, "CTRL1 update failed: %d\n", ret);
 314                         return ret;
 315                 }
 316         }
 317
 318         return ret;
 319 }
 320
 321 static int palmas_gpadc_read_prepare(struct palmas_gpadc *adc, int adc_chan)
 322 {
 323         int ret;
 324
 325         if (palmas_gpadc_channel_is_freerunning(adc, adc_chan))
 326                 return 0; /* ADC already running */
 327
 328         ret = palmas_gpadc_enable(adc, adc_chan, true);
 329         if (ret < 0)
 330                 return ret;
 331
 332         return palmas_gpadc_start_mask_interrupt(adc, 0);
 333 }
 334
 335 static void palmas_gpadc_read_done(struct palmas_gpadc *adc, int adc_chan)
 336 {
 337         palmas_gpadc_start_mask_interrupt(adc, 1);
 338         palmas_gpadc_enable(adc, adc_chan, false);
 339 }
 340
 341 static int palmas_gpadc_calibrate(struct palmas_gpadc *adc, int adc_chan)
 342 {
 343         int k;
 344         int d1;
 345         int d2;
 346         int ret;
 347         int gain;
 348         int x1 =  adc->adc_info[adc_chan].x1;
 349         int x2 =  adc->adc_info[adc_chan].x2;
 350         int v1 = adc->adc_info[adc_chan].v1;
 351         int v2 = adc->adc_info[adc_chan].v2;
 352
 353         ret = palmas_read(adc->palmas, PALMAS_TRIM_GPADC_BASE,
 354                                 adc->adc_info[adc_chan].trim1_reg, &d1);
 355         if (ret < 0) {
 356                 dev_err(adc->dev, "TRIM read failed: %d\n", ret);
 357                 goto scrub;
 358         }
 359
 360         ret = palmas_read(adc->palmas, PALMAS_TRIM_GPADC_BASE,
 361                                 adc->adc_info[adc_chan].trim2_reg, &d2);
 362         if (ret < 0) {
 363                 dev_err(adc->dev, "TRIM read failed: %d\n", ret);
 364                 goto scrub;
 365         }
 366
 367         /* gain error calculation */
 368         k = (1000 + (1000 * (d2 - d1)) / (x2 - x1));
 369
 370         /* gain calculation */
 371         gain = ((v2 - v1) * 1000) / (x2 - x1);
 372
 373         adc->adc_info[adc_chan].gain_error = k;
 374         adc->adc_info[adc_chan].gain = gain;
 375         /* offset Calculation */
 376         adc->adc_info[adc_chan].offset = (d1 * 1000) - ((k - 1000) * x1);
 377
 378 scrub:
 379         return ret;
 380 }
 381
 382 static int palmas_gpadc_start_conversion(struct palmas_gpadc *adc, int adc_chan)
 383 {
 384         unsigned int val;
 385         int ret;
 386
 387         if (palmas_gpadc_channel_is_freerunning(adc, adc_chan)) {
 388                 int event = (adc_chan == adc->event0.channel) ? 0 : 1;
 389                 unsigned int reg = (event == 0) ?
 390                         PALMAS_GPADC_AUTO_CONV0_LSB :
 391                         PALMAS_GPADC_AUTO_CONV1_LSB;
 392
 393                 ret = palmas_bulk_read(adc->palmas, PALMAS_GPADC_BASE,
 394                                         reg, &val, 2);
 395                 if (ret < 0) {
 396                         dev_err(adc->dev, "AUTO_CONV%x_LSB read failed: %d\n",
 397                                 event, ret);
 398                         return ret;
 399                 }
 400         } else {
 401                 init_completion(&adc->conv_completion);
 402                 ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
 403                                         PALMAS_GPADC_SW_SELECT,
 404                                         PALMAS_GPADC_SW_SELECT_SW_START_CONV0,
 405                                         PALMAS_GPADC_SW_SELECT_SW_START_CONV0);
 406                 if (ret < 0) {
 407                         dev_err(adc->dev, "SELECT_SW_START write failed: %d\n", ret);
 408                         return ret;
 409                 }
 410
 411                 ret = wait_for_completion_timeout(&adc->conv_completion,
 412                                         PALMAS_ADC_CONVERSION_TIMEOUT);
 413                 if (ret == 0) {
 414                         dev_err(adc->dev, "conversion not completed\n");
 415                         return -ETIMEDOUT;
 416                 }
 417
 418                 ret = palmas_bulk_read(adc->palmas, PALMAS_GPADC_BASE,
 419                                         PALMAS_GPADC_SW_CONV0_LSB, &val, 2);
 420                 if (ret < 0) {
 421                         dev_err(adc->dev, "SW_CONV0_LSB read failed: %d\n", ret);
 422                         return ret;
 423                 }
 424         }
 425
 426         ret = val & 0xFFF;
 427
 428         return ret;
 429 }
 430
 431 static int palmas_gpadc_get_calibrated_code(struct palmas_gpadc *adc,
 432                                                 int adc_chan, int val)
 433 {
 434         if (!adc->adc_info[adc_chan].is_uncalibrated)
 435                 val  = (val*1000 - adc->adc_info[adc_chan].offset) /
 436                                         adc->adc_info[adc_chan].gain_error;
 437
 438         if (val < 0) {
 439                 if (val < -10)
 440                         dev_err(adc->dev, "Mismatch with calibration var = %d\n", val);
 441                 return 0;
 442         }
 443
 444         val = (val * adc->adc_info[adc_chan].gain) / 1000;
 445
 446         return val;
 447 }
 448
 449 /*
 450  * The high and low threshold values are calculated based on the advice given
 451  * in TI Application Report SLIA087A, "Guide to Using the GPADC in PS65903x,
 452  * TPS65917-Q1, TPS65919-Q1, and TPS65916 Devices". This document recommend
 453  * taking ADC tolerances into account and is based on the device integral non-
 454  * linearity (INL), offset error and gain error:
 455  *
 456  *   raw high threshold = (ideal threshold + INL) * gain error + offset error
 457  *
 458  * The gain error include both gain error, as specified in the datasheet, and
 459  * the gain error drift. These paramenters vary depending on device and whether
 460  * the channel is calibrated (trimmed) or not.
 461  */
 462 static int palmas_gpadc_threshold_with_tolerance(int val, const int INL,
 463                                                  const int gain_error,
 464                                                  const int offset_error)
 465 {
 466         val = ((val + INL) * (1000 + gain_error)) / 1000 + offset_error;
 467
 468         return clamp(val, 0, 0xFFF);
 469 }
 470
 471 /*
 472  * The values below are taken from the datasheet of TWL6035, TWL6037.
 473  * todo: get max INL, gain error, and offset error from OF.
 474  */
 475 static int palmas_gpadc_get_high_threshold_raw(struct palmas_gpadc *adc,
 476                                                struct palmas_adc_event *ev)
 477 {
 478         const int adc_chan = ev->channel;
 479         int val = adc->thresholds[adc_chan].high;
 480         /* integral nonlinearity, measured in LSB */
 481         const int max_INL = 2;
 482         /* measured in LSB */
 483         int max_offset_error;
 484         /* 0.2% when calibrated */
 485         int max_gain_error = 2;
 486
 487         val = (val * 1000) / adc->adc_info[adc_chan].gain;
 488
 489         if (adc->adc_info[adc_chan].is_uncalibrated) {
 490                 /* 2% worse */
 491                 max_gain_error += 20;
 492                 max_offset_error = 36;
 493         } else {
 494                 val = (val * adc->adc_info[adc_chan].gain_error +
 495                        adc->adc_info[adc_chan].offset) /
 496                         1000;
 497                 max_offset_error = 2;
 498         }
 499
 500         return palmas_gpadc_threshold_with_tolerance(val,
 501                                                      max_INL,
 502                                                      max_gain_error,
 503                                                      max_offset_error);
 504 }
 505
 506 /*
 507  * The values below are taken from the datasheet of TWL6035, TWL6037.
 508  * todo: get min INL, gain error, and offset error from OF.
 509  */
 510 static int palmas_gpadc_get_low_threshold_raw(struct palmas_gpadc *adc,
 511                                               struct palmas_adc_event *ev)
 512 {
 513         const int adc_chan = ev->channel;
 514         int val = adc->thresholds[adc_chan].low;
 515         /* integral nonlinearity, measured in LSB */
 516         const int min_INL = -2;
 517         /* measured in LSB */
 518         int min_offset_error;
 519         /* -0.6% when calibrated */
 520         int min_gain_error = -6;
 521
 522         val = (val * 1000) / adc->adc_info[adc_chan].gain;
 523
 524         if (adc->adc_info[adc_chan].is_uncalibrated) {
 525                 /* 2% worse */
 526                 min_gain_error -= 20;
 527                 min_offset_error = -36;
 528         } else {
 529                 val = (val * adc->adc_info[adc_chan].gain_error -
 530                        adc->adc_info[adc_chan].offset) /
 531                         1000;
 532                 min_offset_error = -2;
 533         }
 534
 535         return palmas_gpadc_threshold_with_tolerance(val,
 536                                                      min_INL,
 537                                                      min_gain_error,
 538                                                      min_offset_error);
 539 }
 540
 541 static int palmas_gpadc_read_raw(struct iio_dev *indio_dev,
 542         struct iio_chan_spec const *chan, int *val, int *val2, long mask)
 543 {
 544         struct  palmas_gpadc *adc = iio_priv(indio_dev);
 545         int adc_chan = chan->channel;
 546         int ret = 0;
 547
 548         if (adc_chan >= PALMAS_ADC_CH_MAX)
 549                 return -EINVAL;
 550
 551         mutex_lock(&adc->lock);
 552
 553         switch (mask) {
 554         case IIO_CHAN_INFO_RAW:
 555         case IIO_CHAN_INFO_PROCESSED:
 556                 ret = palmas_gpadc_read_prepare(adc, adc_chan);
 557                 if (ret < 0)
 558                         goto out;
 559
 560                 ret = palmas_gpadc_start_conversion(adc, adc_chan);
 561                 if (ret < 0) {
 562                         dev_err(adc->dev,
 563                         "ADC start conversion failed\n");
 564                         goto out;
 565                 }
 566
 567                 if (mask == IIO_CHAN_INFO_PROCESSED)
 568                         ret = palmas_gpadc_get_calibrated_code(
 569                                                         adc, adc_chan, ret);
 570
 571                 *val = ret;
 572
 573                 ret = IIO_VAL_INT;
 574                 goto out;
 575         }
 576
 577         mutex_unlock(&adc->lock);
 578         return ret;
 579
 580 out:
 581         palmas_gpadc_read_done(adc, adc_chan);
 582         mutex_unlock(&adc->lock);
 583
 584         return ret;
 585 }
 586
 587 static int palmas_gpadc_read_event_config(struct iio_dev *indio_dev,
 588                                           const struct iio_chan_spec *chan,
 589                                           enum iio_event_type type,
 590                                           enum iio_event_direction dir)
 591 {
 592         struct palmas_gpadc *adc = iio_priv(indio_dev);
 593         int adc_chan = chan->channel;
 594         int ret = 0;
 595
 596         if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
 597                 return -EINVAL;
 598
 599         mutex_lock(&adc->lock);
 600
 601         if (palmas_gpadc_get_event(adc, adc_chan, dir))
 602                 ret = 1;
 603
 604         mutex_unlock(&adc->lock);
 605
 606         return ret;
 607 }
 608
 609 static int palmas_adc_configure_events(struct palmas_gpadc *adc);
 610 static int palmas_adc_reset_events(struct palmas_gpadc *adc);
 611
 612 static int palmas_gpadc_reconfigure_event_channels(struct palmas_gpadc *adc)
 613 {
 614         return (adc->event0.enabled || adc->event1.enabled) ?
 615                 palmas_adc_configure_events(adc) :
 616                 palmas_adc_reset_events(adc);
 617 }
 618
 619 static int palmas_gpadc_enable_event_config(struct palmas_gpadc *adc,
 620                                             const struct iio_chan_spec *chan,
 621                                             enum iio_event_direction dir)
 622 {
 623         struct palmas_adc_event *ev;
 624         int adc_chan = chan->channel;
 625
 626         if (palmas_gpadc_get_event(adc, adc_chan, dir))
 627                 /* already enabled */
 628                 return 0;
 629
 630         if (adc->event0.channel == -1) {
 631                 ev = &adc->event0;
 632         } else if (adc->event1.channel == -1) {
 633                 /* event0 has to be the lowest channel */
 634                 if (adc_chan < adc->event0.channel) {
 635                         adc->event1 = adc->event0;
 636                         ev = &adc->event0;
 637                 } else {
 638                         ev = &adc->event1;
 639                 }
 640         } else { /* both AUTO channels already in use */
 641                 dev_warn(adc->dev, "event0 - %d, event1 - %d\n",
 642                          adc->event0.channel, adc->event1.channel);
 643                 return -EBUSY;
 644         }
 645
 646         ev->enabled = true;
 647         ev->channel = adc_chan;
 648         ev->direction = dir;
 649
 650         return palmas_gpadc_reconfigure_event_channels(adc);
 651 }
 652
 653 static int palmas_gpadc_disable_event_config(struct palmas_gpadc *adc,
 654                                              const struct iio_chan_spec *chan,
 655                                              enum iio_event_direction dir)
 656 {
 657         int adc_chan = chan->channel;
 658         struct palmas_adc_event *ev = palmas_gpadc_get_event(adc, adc_chan, dir);
 659
 660         if (!ev)
 661                 return 0;
 662
 663         if (ev == &adc->event0) {
 664                 adc->event0 = adc->event1;
 665                 ev = &adc->event1;
 666         }
 667
 668         ev->enabled = false;
 669         ev->channel = -1;
 670         ev->direction = IIO_EV_DIR_NONE;
 671
 672         return palmas_gpadc_reconfigure_event_channels(adc);
 673 }
 674
 675 static int palmas_gpadc_write_event_config(struct iio_dev *indio_dev,
 676                                            const struct iio_chan_spec *chan,
 677                                            enum iio_event_type type,
 678                                            enum iio_event_direction dir,
 679                                            int state)
 680 {
 681         struct palmas_gpadc *adc = iio_priv(indio_dev);
 682         int adc_chan = chan->channel;
 683         int ret;
 684
 685         if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
 686                 return -EINVAL;
 687
 688         mutex_lock(&adc->lock);
 689
 690         if (state)
 691                 ret = palmas_gpadc_enable_event_config(adc, chan, dir);
 692         else
 693                 ret = palmas_gpadc_disable_event_config(adc, chan, dir);
 694
 695         mutex_unlock(&adc->lock);
 696
 697         return ret;
 698 }
 699
 700 static int palmas_gpadc_read_event_value(struct iio_dev *indio_dev,
 701                                          const struct iio_chan_spec *chan,
 702                                          enum iio_event_type type,
 703                                          enum iio_event_direction dir,
 704                                          enum iio_event_info info,
 705                                          int *val, int *val2)
 706 {
 707         struct palmas_gpadc *adc = iio_priv(indio_dev);
 708         int adc_chan = chan->channel;
 709         int ret;
 710
 711         if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
 712                 return -EINVAL;
 713
 714         mutex_lock(&adc->lock);
 715
 716         switch (info) {
 717         case IIO_EV_INFO_VALUE:
 718                 *val = (dir == IIO_EV_DIR_RISING) ?
 719                         adc->thresholds[adc_chan].high :
 720                         adc->thresholds[adc_chan].low;
 721                 ret = IIO_VAL_INT;
 722                 break;
 723         default:
 724                 ret = -EINVAL;
 725                 break;
 726         }
 727
 728         mutex_unlock(&adc->lock);
 729
 730         return ret;
 731 }
 732
 733 static int palmas_gpadc_write_event_value(struct iio_dev *indio_dev,
 734                                           const struct iio_chan_spec *chan,
 735                                           enum iio_event_type type,
 736                                           enum iio_event_direction dir,
 737                                           enum iio_event_info info,
 738                                           int val, int val2)
 739 {
 740         struct palmas_gpadc *adc = iio_priv(indio_dev);
 741         int adc_chan = chan->channel;
 742         int old;
 743         int ret;
 744
 745         if (adc_chan >= PALMAS_ADC_CH_MAX || type != IIO_EV_TYPE_THRESH)
 746                 return -EINVAL;
 747
 748         mutex_lock(&adc->lock);
 749         switch (info) {
 750         case IIO_EV_INFO_VALUE:
 751                 if (val < 0 || val > 0xFFF) {
 752                         ret = -EINVAL;
 753                         goto out_unlock;
 754                 }
 755                 if (dir == IIO_EV_DIR_RISING) {
 756                         old = adc->thresholds[adc_chan].high;
 757                         adc->thresholds[adc_chan].high = val;
 758                 } else {
 759                         old = adc->thresholds[adc_chan].low;
 760                         adc->thresholds[adc_chan].low = val;
 761                 }
 762                 ret = 0;
 763                 break;
 764         default:
 765                 ret = -EINVAL;
 766                 goto out_unlock;
 767         }
 768
 769         if (val != old && palmas_gpadc_get_event(adc, adc_chan, dir))
 770                 ret = palmas_gpadc_reconfigure_event_channels(adc);
 771
 772 out_unlock:
 773         mutex_unlock(&adc->lock);
 774
 775         return ret;
 776 }
 777
 778 static const struct iio_info palmas_gpadc_iio_info = {
 779         .read_raw = palmas_gpadc_read_raw,
 780         .read_event_config = palmas_gpadc_read_event_config,
 781         .write_event_config = palmas_gpadc_write_event_config,
 782         .read_event_value = palmas_gpadc_read_event_value,
 783         .write_event_value = palmas_gpadc_write_event_value,
 784 };
 785
 786 static const struct iio_event_spec palmas_gpadc_events[] = {
 787         {
 788                 .type = IIO_EV_TYPE_THRESH,
 789                 .dir = IIO_EV_DIR_RISING,
 790                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 791                                 BIT(IIO_EV_INFO_ENABLE),
 792         }, {
 793                 .type = IIO_EV_TYPE_THRESH,
 794                 .dir = IIO_EV_DIR_FALLING,
 795                 .mask_separate = BIT(IIO_EV_INFO_VALUE) |
 796                                 BIT(IIO_EV_INFO_ENABLE),
 797         },
 798 };
 799
 800 #define PALMAS_ADC_CHAN_IIO(chan, _type, chan_info)     \
 801 {                                                       \
 802         .datasheet_name = PALMAS_DATASHEET_NAME(chan),  \
 803         .type = _type,                                  \
 804         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |  \
 805                         BIT(chan_info),                 \
 806         .indexed = 1,                                   \
 807         .channel = PALMAS_ADC_CH_##chan,                \
 808         .event_spec = palmas_gpadc_events,              \
 809         .num_event_specs = ARRAY_SIZE(palmas_gpadc_events)      \
 810 }
 811
 812 static const struct iio_chan_spec palmas_gpadc_iio_channel[] = {
 813         PALMAS_ADC_CHAN_IIO(IN0, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 814         PALMAS_ADC_CHAN_IIO(IN1, IIO_TEMP, IIO_CHAN_INFO_RAW),
 815         PALMAS_ADC_CHAN_IIO(IN2, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 816         PALMAS_ADC_CHAN_IIO(IN3, IIO_TEMP, IIO_CHAN_INFO_RAW),
 817         PALMAS_ADC_CHAN_IIO(IN4, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 818         PALMAS_ADC_CHAN_IIO(IN5, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 819         PALMAS_ADC_CHAN_IIO(IN6, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 820         PALMAS_ADC_CHAN_IIO(IN7, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 821         PALMAS_ADC_CHAN_IIO(IN8, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 822         PALMAS_ADC_CHAN_IIO(IN9, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 823         PALMAS_ADC_CHAN_IIO(IN10, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 824         PALMAS_ADC_CHAN_IIO(IN11, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 825         PALMAS_ADC_CHAN_IIO(IN12, IIO_TEMP, IIO_CHAN_INFO_RAW),
 826         PALMAS_ADC_CHAN_IIO(IN13, IIO_TEMP, IIO_CHAN_INFO_RAW),
 827         PALMAS_ADC_CHAN_IIO(IN14, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 828         PALMAS_ADC_CHAN_IIO(IN15, IIO_VOLTAGE, IIO_CHAN_INFO_PROCESSED),
 829 };
 830
 831 static int palmas_gpadc_get_adc_dt_data(struct platform_device *pdev,
 832         struct palmas_gpadc_platform_data **gpadc_pdata)
 833 {
 834         struct device_node *np = pdev->dev.of_node;
 835         struct palmas_gpadc_platform_data *gp_data;
 836         int ret;
 837         u32 pval;
 838
 839         gp_data = devm_kzalloc(&pdev->dev, sizeof(*gp_data), GFP_KERNEL);
 840         if (!gp_data)
 841                 return -ENOMEM;
 842
 843         ret = of_property_read_u32(np, "ti,channel0-current-microamp", &pval);
 844         if (!ret)
 845                 gp_data->ch0_current = pval;
 846
 847         ret = of_property_read_u32(np, "ti,channel3-current-microamp", &pval);
 848         if (!ret)
 849                 gp_data->ch3_current = pval;
 850
 851         gp_data->extended_delay = of_property_read_bool(np,
 852                                         "ti,enable-extended-delay");
 853
 854         *gpadc_pdata = gp_data;
 855
 856         return 0;
 857 }
 858
 859 static void palmas_gpadc_reset(void *data)
 860 {
 861         struct palmas_gpadc *adc = data;
 862         if (adc->event0.enabled || adc->event1.enabled)
 863                 palmas_adc_reset_events(adc);
 864 }
 865
 866 static int palmas_gpadc_probe(struct platform_device *pdev)
 867 {
 868         struct palmas_gpadc *adc;
 869         struct palmas_platform_data *pdata;
 870         struct palmas_gpadc_platform_data *gpadc_pdata = NULL;
 871         struct iio_dev *indio_dev;
 872         int ret, i;
 873
 874         pdata = dev_get_platdata(pdev->dev.parent);
 875
 876         if (pdata && pdata->gpadc_pdata)
 877                 gpadc_pdata = pdata->gpadc_pdata;
 878
 879         if (!gpadc_pdata && pdev->dev.of_node) {
 880                 ret = palmas_gpadc_get_adc_dt_data(pdev, &gpadc_pdata);
 881                 if (ret < 0)
 882                         return ret;
 883         }
 884         if (!gpadc_pdata)
 885                 return -EINVAL;
 886
 887         indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
 888         if (!indio_dev) {
 889                 dev_err(&pdev->dev, "iio_device_alloc failed\n");
 890                 return -ENOMEM;
 891         }
 892
 893         adc = iio_priv(indio_dev);
 894         adc->dev = &pdev->dev;
 895         adc->palmas = dev_get_drvdata(pdev->dev.parent);
 896         adc->adc_info = palmas_gpadc_info;
 897
 898         mutex_init(&adc->lock);
 899
 900         init_completion(&adc->conv_completion);
 901         platform_set_drvdata(pdev, indio_dev);
 902
 903         adc->auto_conversion_period = gpadc_pdata->auto_conversion_period_ms;
 904         adc->irq = palmas_irq_get_virq(adc->palmas, PALMAS_GPADC_EOC_SW_IRQ);
 905         if (adc->irq < 0)
 906                 return dev_err_probe(adc->dev, adc->irq, "get virq failed\n");
 907
 908         ret = devm_request_threaded_irq(&pdev->dev, adc->irq, NULL,
 909                                         palmas_gpadc_irq,
 910                                         IRQF_ONESHOT, dev_name(adc->dev),
 911                                         adc);
 912         if (ret < 0)
 913                 return dev_err_probe(adc->dev, ret,
 914                                      "request irq %d failed\n", adc->irq);
 915
 916         adc->irq_auto_0 = platform_get_irq(pdev, 1);
 917         if (adc->irq_auto_0 < 0)
 918                 return adc->irq_auto_0;
 919
 920         ret = devm_request_threaded_irq(&pdev->dev, adc->irq_auto_0, NULL,
 921                                         palmas_gpadc_irq_auto, IRQF_ONESHOT,
 922                                         "palmas-adc-auto-0", indio_dev);
 923         if (ret < 0)
 924                 return dev_err_probe(adc->dev, ret,
 925                                      "request auto0 irq %d failed\n",
 926                                      adc->irq_auto_0);
 927
 928         adc->irq_auto_1 = platform_get_irq(pdev, 2);
 929         if (adc->irq_auto_1 < 0)
 930                 return adc->irq_auto_1;
 931
 932         ret = devm_request_threaded_irq(&pdev->dev, adc->irq_auto_1, NULL,
 933                                         palmas_gpadc_irq_auto, IRQF_ONESHOT,
 934                                         "palmas-adc-auto-1", indio_dev);
 935         if (ret < 0)
 936                 return dev_err_probe(adc->dev, ret,
 937                                      "request auto1 irq %d failed\n",
 938                                      adc->irq_auto_1);
 939
 940         adc->event0.enabled = false;
 941         adc->event0.channel = -1;
 942         adc->event0.direction = IIO_EV_DIR_NONE;
 943         adc->event1.enabled = false;
 944         adc->event1.channel = -1;
 945         adc->event1.direction = IIO_EV_DIR_NONE;
 946
 947         /* set the current source 0 (value 0/5/15/20 uA => 0..3) */
 948         if (gpadc_pdata->ch0_current <= 1)
 949                 adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_0;
 950         else if (gpadc_pdata->ch0_current <= 5)
 951                 adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_5;
 952         else if (gpadc_pdata->ch0_current <= 15)
 953                 adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_15;
 954         else
 955                 adc->ch0_current = PALMAS_ADC_CH0_CURRENT_SRC_20;
 956
 957         /* set the current source 3 (value 0/10/400/800 uA => 0..3) */
 958         if (gpadc_pdata->ch3_current <= 1)
 959                 adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_0;
 960         else if (gpadc_pdata->ch3_current <= 10)
 961                 adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_10;
 962         else if (gpadc_pdata->ch3_current <= 400)
 963                 adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_400;
 964         else
 965                 adc->ch3_current = PALMAS_ADC_CH3_CURRENT_SRC_800;
 966
 967         adc->extended_delay = gpadc_pdata->extended_delay;
 968
 969         indio_dev->name = MOD_NAME;
 970         indio_dev->info = &palmas_gpadc_iio_info;
 971         indio_dev->modes = INDIO_DIRECT_MODE;
 972         indio_dev->channels = palmas_gpadc_iio_channel;
 973         indio_dev->num_channels = ARRAY_SIZE(palmas_gpadc_iio_channel);
 974
 975         ret = devm_iio_device_register(&pdev->dev, indio_dev);
 976         if (ret < 0)
 977                 return dev_err_probe(adc->dev, ret,
 978                                      "iio_device_register() failed\n");
 979
 980         device_set_wakeup_capable(&pdev->dev, 1);
 981         for (i = 0; i < PALMAS_ADC_CH_MAX; i++) {
 982                 if (!(adc->adc_info[i].is_uncalibrated))
 983                         palmas_gpadc_calibrate(adc, i);
 984         }
 985
 986         ret = devm_add_action(&pdev->dev, palmas_gpadc_reset, adc);
 987         if (ret)
 988                 return ret;
 989
 990         return 0;
 991 }
 992
 993 static int palmas_adc_configure_events(struct palmas_gpadc *adc)
 994 {
 995         int adc_period, conv;
 996         int i;
 997         int ch0 = 0, ch1 = 0;
 998         int thres;
 999         int ret;
1000
1001         adc_period = adc->auto_conversion_period;
1002         for (i = 0; i < 16; ++i) {
1003                 if (((1000 * (1 << i)) / 32) >= adc_period)
1004                         break;
1005         }
1006         if (i > 0)
1007                 i--;
1008         adc_period = i;
1009         ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
1010                         PALMAS_GPADC_AUTO_CTRL,
1011                         PALMAS_GPADC_AUTO_CTRL_COUNTER_CONV_MASK,
1012                         adc_period);
1013         if (ret < 0) {
1014                 dev_err(adc->dev, "AUTO_CTRL write failed: %d\n", ret);
1015                 return ret;
1016         }
1017
1018         conv = 0;
1019         if (adc->event0.enabled) {
1020                 struct palmas_adc_event *ev = &adc->event0;
1021                 int polarity;
1022
1023                 ch0 = ev->channel;
1024                 conv |= PALMAS_GPADC_AUTO_CTRL_AUTO_CONV0_EN;
1025                 switch (ev->direction) {
1026                 case IIO_EV_DIR_RISING:
1027                         thres = palmas_gpadc_get_high_threshold_raw(adc, ev);
1028                         polarity = 0;
1029                         break;
1030                 case IIO_EV_DIR_FALLING:
1031                         thres = palmas_gpadc_get_low_threshold_raw(adc, ev);
1032                         polarity = PALMAS_GPADC_THRES_CONV0_MSB_THRES_CONV0_POL;
1033                         break;
1034                 default:
1035                         return -EINVAL;
1036                 }
1037
1038                 ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1039                                 PALMAS_GPADC_THRES_CONV0_LSB, thres & 0xFF);
1040                 if (ret < 0) {
1041                         dev_err(adc->dev,
1042                                 "THRES_CONV0_LSB write failed: %d\n", ret);
1043                         return ret;
1044                 }
1045
1046                 ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1047                                 PALMAS_GPADC_THRES_CONV0_MSB,
1048                                 ((thres >> 8) & 0xF) | polarity);
1049                 if (ret < 0) {
1050                         dev_err(adc->dev,
1051                                 "THRES_CONV0_MSB write failed: %d\n", ret);
1052                         return ret;
1053                 }
1054         }
1055
1056         if (adc->event1.enabled) {
1057                 struct palmas_adc_event *ev = &adc->event1;
1058                 int polarity;
1059
1060                 ch1 = ev->channel;
1061                 conv |= PALMAS_GPADC_AUTO_CTRL_AUTO_CONV1_EN;
1062                 switch (ev->direction) {
1063                 case IIO_EV_DIR_RISING:
1064                         thres = palmas_gpadc_get_high_threshold_raw(adc, ev);
1065                         polarity = 0;
1066                         break;
1067                 case IIO_EV_DIR_FALLING:
1068                         thres = palmas_gpadc_get_low_threshold_raw(adc, ev);
1069                         polarity = PALMAS_GPADC_THRES_CONV1_MSB_THRES_CONV1_POL;
1070                         break;
1071                 default:
1072                         return -EINVAL;
1073                 }
1074
1075                 ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1076                                 PALMAS_GPADC_THRES_CONV1_LSB, thres & 0xFF);
1077                 if (ret < 0) {
1078                         dev_err(adc->dev,
1079                                 "THRES_CONV1_LSB write failed: %d\n", ret);
1080                         return ret;
1081                 }
1082
1083                 ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1084                                 PALMAS_GPADC_THRES_CONV1_MSB,
1085                                 ((thres >> 8) & 0xF) | polarity);
1086                 if (ret < 0) {
1087                         dev_err(adc->dev,
1088                                 "THRES_CONV1_MSB write failed: %d\n", ret);
1089                         return ret;
1090                 }
1091         }
1092
1093         ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1094                         PALMAS_GPADC_AUTO_SELECT, (ch1 << 4) | ch0);
1095         if (ret < 0) {
1096                 dev_err(adc->dev, "AUTO_SELECT write failed: %d\n", ret);
1097                 return ret;
1098         }
1099
1100         ret = palmas_update_bits(adc->palmas, PALMAS_GPADC_BASE,
1101                         PALMAS_GPADC_AUTO_CTRL,
1102                         PALMAS_GPADC_AUTO_CTRL_AUTO_CONV1_EN |
1103                         PALMAS_GPADC_AUTO_CTRL_AUTO_CONV0_EN, conv);
1104         if (ret < 0)
1105                 dev_err(adc->dev, "AUTO_CTRL write failed: %d\n", ret);
1106
1107         return ret;
1108 }
1109
1110 static int palmas_adc_reset_events(struct palmas_gpadc *adc)
1111 {
1112         int ret;
1113
1114         ret = palmas_write(adc->palmas, PALMAS_GPADC_BASE,
1115                         PALMAS_GPADC_AUTO_SELECT, 0);
1116         if (ret < 0) {
1117                 dev_err(adc->dev, "AUTO_SELECT write failed: %d\n", ret);
1118                 return ret;
1119         }
1120
1121         ret = palmas_disable_auto_conversion(adc);
1122         if (ret < 0)
1123                 dev_err(adc->dev, "Disable auto conversion failed: %d\n", ret);
1124
1125         return ret;
1126 }
1127
1128 static int palmas_gpadc_suspend(struct device *dev)
1129 {
1130         struct iio_dev *indio_dev = dev_get_drvdata(dev);
1131         struct palmas_gpadc *adc = iio_priv(indio_dev);
1132
1133         if (!device_may_wakeup(dev))
1134                 return 0;
1135
1136         if (adc->event0.enabled)
1137                 enable_irq_wake(adc->irq_auto_0);
1138
1139         if (adc->event1.enabled)
1140                 enable_irq_wake(adc->irq_auto_1);
1141
1142         return 0;
1143 }
1144
1145 static int palmas_gpadc_resume(struct device *dev)
1146 {
1147         struct iio_dev *indio_dev = dev_get_drvdata(dev);
1148         struct palmas_gpadc *adc = iio_priv(indio_dev);
1149
1150         if (!device_may_wakeup(dev))
1151                 return 0;
1152
1153         if (adc->event0.enabled)
1154                 disable_irq_wake(adc->irq_auto_0);
1155
1156         if (adc->event1.enabled)
1157                 disable_irq_wake(adc->irq_auto_1);
1158
1159         return 0;
1160 };
1161
1162 static DEFINE_SIMPLE_DEV_PM_OPS(palmas_pm_ops, palmas_gpadc_suspend,
1163                                 palmas_gpadc_resume);
1164
1165 static const struct of_device_id of_palmas_gpadc_match_tbl[] = {
1166         { .compatible = "ti,palmas-gpadc", },
1167         { /* end */ }
1168 };
1169 MODULE_DEVICE_TABLE(of, of_palmas_gpadc_match_tbl);
1170
1171 static struct platform_driver palmas_gpadc_driver = {
1172         .probe = palmas_gpadc_probe,
1173         .driver = {
1174                 .name = MOD_NAME,
1175                 .pm = pm_sleep_ptr(&palmas_pm_ops),
1176                 .of_match_table = of_palmas_gpadc_match_tbl,
1177         },
1178 };
1179 module_platform_driver(palmas_gpadc_driver);
1180
1181 MODULE_DESCRIPTION("palmas GPADC driver");
1182 MODULE_AUTHOR("Pradeep Goudagunta<pgoudagunta@nvidia.com>");
1183 MODULE_ALIAS("platform:palmas-gpadc");
1184 MODULE_LICENSE("GPL v2");