drivers/iio/proximity/sx9500.c

   1 /*
   2  * Copyright (c) 2014 Intel Corporation
   3  *
   4  * Driver for Semtech's SX9500 capacitive proximity/button solution.
   5  * Datasheet available at
   6  * <http://www.semtech.com/images/datasheet/sx9500.pdf>.
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License version 2 as published by
  10  * the Free Software Foundation.
  11  */
  12
  13 #include <linux/kernel.h>
  14 #include <linux/slab.h>
  15 #include <linux/module.h>
  16 #include <linux/i2c.h>
  17 #include <linux/irq.h>
  18 #include <linux/acpi.h>
  19 #include <linux/gpio/consumer.h>
  20 #include <linux/regmap.h>
  21 #include <linux/pm.h>
  22 #include <linux/delay.h>
  23
  24 #include <linux/iio/iio.h>
  25 #include <linux/iio/buffer.h>
  26 #include <linux/iio/sysfs.h>
  27 #include <linux/iio/events.h>
  28 #include <linux/iio/trigger.h>
  29 #include <linux/iio/triggered_buffer.h>
  30 #include <linux/iio/trigger_consumer.h>
  31
  32 #define SX9500_DRIVER_NAME              "sx9500"
  33 #define SX9500_IRQ_NAME                 "sx9500_event"
  34
  35 #define SX9500_GPIO_INT                 "interrupt"
  36 #define SX9500_GPIO_RESET               "reset"
  37
  38 /* Register definitions. */
  39 #define SX9500_REG_IRQ_SRC              0x00
  40 #define SX9500_REG_STAT                 0x01
  41 #define SX9500_REG_IRQ_MSK              0x03
  42
  43 #define SX9500_REG_PROX_CTRL0           0x06
  44 #define SX9500_REG_PROX_CTRL1           0x07
  45 #define SX9500_REG_PROX_CTRL2           0x08
  46 #define SX9500_REG_PROX_CTRL3           0x09
  47 #define SX9500_REG_PROX_CTRL4           0x0a
  48 #define SX9500_REG_PROX_CTRL5           0x0b
  49 #define SX9500_REG_PROX_CTRL6           0x0c
  50 #define SX9500_REG_PROX_CTRL7           0x0d
  51 #define SX9500_REG_PROX_CTRL8           0x0e
  52
  53 #define SX9500_REG_SENSOR_SEL           0x20
  54 #define SX9500_REG_USE_MSB              0x21
  55 #define SX9500_REG_USE_LSB              0x22
  56 #define SX9500_REG_AVG_MSB              0x23
  57 #define SX9500_REG_AVG_LSB              0x24
  58 #define SX9500_REG_DIFF_MSB             0x25
  59 #define SX9500_REG_DIFF_LSB             0x26
  60 #define SX9500_REG_OFFSET_MSB           0x27
  61 #define SX9500_REG_OFFSET_LSB           0x28
  62
  63 #define SX9500_REG_RESET                0x7f
  64
  65 /* Write this to REG_RESET to do a soft reset. */
  66 #define SX9500_SOFT_RESET               0xde
  67
  68 #define SX9500_SCAN_PERIOD_MASK         GENMASK(6, 4)
  69 #define SX9500_SCAN_PERIOD_SHIFT        4
  70
  71 /*
  72  * These serve for identifying IRQ source in the IRQ_SRC register, and
  73  * also for masking the IRQs in the IRQ_MSK register.
  74  */
  75 #define SX9500_CLOSE_IRQ                BIT(6)
  76 #define SX9500_FAR_IRQ                  BIT(5)
  77 #define SX9500_CONVDONE_IRQ             BIT(3)
  78
  79 #define SX9500_PROXSTAT_SHIFT           4
  80 #define SX9500_COMPSTAT_MASK            GENMASK(3, 0)
  81
  82 #define SX9500_NUM_CHANNELS             4
  83 #define SX9500_CHAN_MASK                GENMASK(SX9500_NUM_CHANNELS - 1, 0)
  84
  85 struct sx9500_data {
  86         struct mutex mutex;
  87         struct i2c_client *client;
  88         struct iio_trigger *trig;
  89         struct regmap *regmap;
  90         struct gpio_desc *gpiod_rst;
  91         /*
  92          * Last reading of the proximity status for each channel.  We
  93          * only send an event to user space when this changes.
  94          */
  95         bool prox_stat[SX9500_NUM_CHANNELS];
  96         bool event_enabled[SX9500_NUM_CHANNELS];
  97         bool trigger_enabled;
  98         u16 *buffer;
  99         /* Remember enabled channels and sample rate during suspend. */
 100         unsigned int suspend_ctrl0;
 101         struct completion completion;
 102         int data_rdy_users, close_far_users;
 103         int channel_users[SX9500_NUM_CHANNELS];
 104 };
 105
 106 static const struct iio_event_spec sx9500_events[] = {
 107         {
 108                 .type = IIO_EV_TYPE_THRESH,
 109                 .dir = IIO_EV_DIR_EITHER,
 110                 .mask_separate = BIT(IIO_EV_INFO_ENABLE),
 111         },
 112 };
 113
 114 #define SX9500_CHANNEL(idx)                                     \
 115         {                                                       \
 116                 .type = IIO_PROXIMITY,                          \
 117                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
 118                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
 119                 .indexed = 1,                                   \
 120                 .channel = idx,                                 \
 121                 .event_spec = sx9500_events,                    \
 122                 .num_event_specs = ARRAY_SIZE(sx9500_events),   \
 123                 .scan_index = idx,                              \
 124                 .scan_type = {                                  \
 125                         .sign = 'u',                            \
 126                         .realbits = 16,                         \
 127                         .storagebits = 16,                      \
 128                         .shift = 0,                             \
 129                 },                                              \
 130         }
 131
 132 static const struct iio_chan_spec sx9500_channels[] = {
 133         SX9500_CHANNEL(0),
 134         SX9500_CHANNEL(1),
 135         SX9500_CHANNEL(2),
 136         SX9500_CHANNEL(3),
 137         IIO_CHAN_SOFT_TIMESTAMP(4),
 138 };
 139
 140 static const struct {
 141         int val;
 142         int val2;
 143 } sx9500_samp_freq_table[] = {
 144         {33, 333333},
 145         {16, 666666},
 146         {11, 111111},
 147         {8, 333333},
 148         {6, 666666},
 149         {5, 0},
 150         {3, 333333},
 151         {2, 500000},
 152 };
 153
 154 static const unsigned int sx9500_scan_period_table[] = {
 155         30, 60, 90, 120, 150, 200, 300, 400,
 156 };
 157
 158 static const struct regmap_range sx9500_writable_reg_ranges[] = {
 159         regmap_reg_range(SX9500_REG_IRQ_MSK, SX9500_REG_IRQ_MSK),
 160         regmap_reg_range(SX9500_REG_PROX_CTRL0, SX9500_REG_PROX_CTRL8),
 161         regmap_reg_range(SX9500_REG_SENSOR_SEL, SX9500_REG_SENSOR_SEL),
 162         regmap_reg_range(SX9500_REG_OFFSET_MSB, SX9500_REG_OFFSET_LSB),
 163         regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
 164 };
 165
 166 static const struct regmap_access_table sx9500_writeable_regs = {
 167         .yes_ranges = sx9500_writable_reg_ranges,
 168         .n_yes_ranges = ARRAY_SIZE(sx9500_writable_reg_ranges),
 169 };
 170
 171 /*
 172  * All allocated registers are readable, so we just list unallocated
 173  * ones.
 174  */
 175 static const struct regmap_range sx9500_non_readable_reg_ranges[] = {
 176         regmap_reg_range(SX9500_REG_STAT + 1, SX9500_REG_STAT + 1),
 177         regmap_reg_range(SX9500_REG_IRQ_MSK + 1, SX9500_REG_PROX_CTRL0 - 1),
 178         regmap_reg_range(SX9500_REG_PROX_CTRL8 + 1, SX9500_REG_SENSOR_SEL - 1),
 179         regmap_reg_range(SX9500_REG_OFFSET_LSB + 1, SX9500_REG_RESET - 1),
 180 };
 181
 182 static const struct regmap_access_table sx9500_readable_regs = {
 183         .no_ranges = sx9500_non_readable_reg_ranges,
 184         .n_no_ranges = ARRAY_SIZE(sx9500_non_readable_reg_ranges),
 185 };
 186
 187 static const struct regmap_range sx9500_volatile_reg_ranges[] = {
 188         regmap_reg_range(SX9500_REG_IRQ_SRC, SX9500_REG_STAT),
 189         regmap_reg_range(SX9500_REG_USE_MSB, SX9500_REG_OFFSET_LSB),
 190         regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
 191 };
 192
 193 static const struct regmap_access_table sx9500_volatile_regs = {
 194         .yes_ranges = sx9500_volatile_reg_ranges,
 195         .n_yes_ranges = ARRAY_SIZE(sx9500_volatile_reg_ranges),
 196 };
 197
 198 static const struct regmap_config sx9500_regmap_config = {
 199         .reg_bits = 8,
 200         .val_bits = 8,
 201
 202         .max_register = SX9500_REG_RESET,
 203         .cache_type = REGCACHE_RBTREE,
 204
 205         .wr_table = &sx9500_writeable_regs,
 206         .rd_table = &sx9500_readable_regs,
 207         .volatile_table = &sx9500_volatile_regs,
 208 };
 209
 210 static int sx9500_inc_users(struct sx9500_data *data, int *counter,
 211                             unsigned int reg, unsigned int bitmask)
 212 {
 213         (*counter)++;
 214         if (*counter != 1)
 215                 /* Bit is already active, nothing to do. */
 216                 return 0;
 217
 218         return regmap_update_bits(data->regmap, reg, bitmask, bitmask);
 219 }
 220
 221 static int sx9500_dec_users(struct sx9500_data *data, int *counter,
 222                             unsigned int reg, unsigned int bitmask)
 223 {
 224         (*counter)--;
 225         if (*counter != 0)
 226                 /* There are more users, do not deactivate. */
 227                 return 0;
 228
 229         return regmap_update_bits(data->regmap, reg, bitmask, 0);
 230 }
 231
 232 static int sx9500_inc_chan_users(struct sx9500_data *data, int chan)
 233 {
 234         return sx9500_inc_users(data, &data->channel_users[chan],
 235                                 SX9500_REG_PROX_CTRL0, BIT(chan));
 236 }
 237
 238 static int sx9500_dec_chan_users(struct sx9500_data *data, int chan)
 239 {
 240         return sx9500_dec_users(data, &data->channel_users[chan],
 241                                 SX9500_REG_PROX_CTRL0, BIT(chan));
 242 }
 243
 244 static int sx9500_inc_data_rdy_users(struct sx9500_data *data)
 245 {
 246         return sx9500_inc_users(data, &data->data_rdy_users,
 247                                 SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
 248 }
 249
 250 static int sx9500_dec_data_rdy_users(struct sx9500_data *data)
 251 {
 252         return sx9500_dec_users(data, &data->data_rdy_users,
 253                                 SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
 254 }
 255
 256 static int sx9500_inc_close_far_users(struct sx9500_data *data)
 257 {
 258         return sx9500_inc_users(data, &data->close_far_users,
 259                                 SX9500_REG_IRQ_MSK,
 260                                 SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
 261 }
 262
 263 static int sx9500_dec_close_far_users(struct sx9500_data *data)
 264 {
 265         return sx9500_dec_users(data, &data->close_far_users,
 266                                 SX9500_REG_IRQ_MSK,
 267                                 SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
 268 }
 269
 270 static int sx9500_read_prox_data(struct sx9500_data *data,
 271                                  const struct iio_chan_spec *chan,
 272                                  int *val)
 273 {
 274         int ret;
 275         __be16 regval;
 276
 277         ret = regmap_write(data->regmap, SX9500_REG_SENSOR_SEL, chan->channel);
 278         if (ret < 0)
 279                 return ret;
 280
 281         ret = regmap_bulk_read(data->regmap, SX9500_REG_USE_MSB, &regval, 2);
 282         if (ret < 0)
 283                 return ret;
 284
 285         *val = be16_to_cpu(regval);
 286
 287         return IIO_VAL_INT;
 288 }
 289
 290 /*
 291  * If we have no interrupt support, we have to wait for a scan period
 292  * after enabling a channel to get a result.
 293  */
 294 static int sx9500_wait_for_sample(struct sx9500_data *data)
 295 {
 296         int ret;
 297         unsigned int val;
 298
 299         ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0, &val);
 300         if (ret < 0)
 301                 return ret;
 302
 303         val = (val & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
 304
 305         msleep(sx9500_scan_period_table[val]);
 306
 307         return 0;
 308 }
 309
 310 static int sx9500_read_proximity(struct sx9500_data *data,
 311                                  const struct iio_chan_spec *chan,
 312                                  int *val)
 313 {
 314         int ret;
 315
 316         mutex_lock(&data->mutex);
 317
 318         ret = sx9500_inc_chan_users(data, chan->channel);
 319         if (ret < 0)
 320                 goto out;
 321
 322         ret = sx9500_inc_data_rdy_users(data);
 323         if (ret < 0)
 324                 goto out_dec_chan;
 325
 326         mutex_unlock(&data->mutex);
 327
 328         if (data->client->irq > 0)
 329                 ret = wait_for_completion_interruptible(&data->completion);
 330         else
 331                 ret = sx9500_wait_for_sample(data);
 332
 333         mutex_lock(&data->mutex);
 334
 335         if (ret < 0)
 336                 goto out_dec_data_rdy;
 337
 338         ret = sx9500_read_prox_data(data, chan, val);
 339         if (ret < 0)
 340                 goto out_dec_data_rdy;
 341
 342         ret = sx9500_dec_data_rdy_users(data);
 343         if (ret < 0)
 344                 goto out_dec_chan;
 345
 346         ret = sx9500_dec_chan_users(data, chan->channel);
 347         if (ret < 0)
 348                 goto out;
 349
 350         ret = IIO_VAL_INT;
 351
 352         goto out;
 353
 354 out_dec_data_rdy:
 355         sx9500_dec_data_rdy_users(data);
 356 out_dec_chan:
 357         sx9500_dec_chan_users(data, chan->channel);
 358 out:
 359         mutex_unlock(&data->mutex);
 360         reinit_completion(&data->completion);
 361
 362         return ret;
 363 }
 364
 365 static int sx9500_read_samp_freq(struct sx9500_data *data,
 366                                  int *val, int *val2)
 367 {
 368         int ret;
 369         unsigned int regval;
 370
 371         mutex_lock(&data->mutex);
 372         ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0, &regval);
 373         mutex_unlock(&data->mutex);
 374
 375         if (ret < 0)
 376                 return ret;
 377
 378         regval = (regval & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
 379         *val = sx9500_samp_freq_table[regval].val;
 380         *val2 = sx9500_samp_freq_table[regval].val2;
 381
 382         return IIO_VAL_INT_PLUS_MICRO;
 383 }
 384
 385 static int sx9500_read_raw(struct iio_dev *indio_dev,
 386                            const struct iio_chan_spec *chan,
 387                            int *val, int *val2, long mask)
 388 {
 389         struct sx9500_data *data = iio_priv(indio_dev);
 390
 391         switch (chan->type) {
 392         case IIO_PROXIMITY:
 393                 switch (mask) {
 394                 case IIO_CHAN_INFO_RAW:
 395                         if (iio_buffer_enabled(indio_dev))
 396                                 return -EBUSY;
 397                         return sx9500_read_proximity(data, chan, val);
 398                 case IIO_CHAN_INFO_SAMP_FREQ:
 399                         return sx9500_read_samp_freq(data, val, val2);
 400                 default:
 401                         return -EINVAL;
 402                 }
 403         default:
 404                 return -EINVAL;
 405         }
 406 }
 407
 408 static int sx9500_set_samp_freq(struct sx9500_data *data,
 409                                 int val, int val2)
 410 {
 411         int i, ret;
 412
 413         for (i = 0; i < ARRAY_SIZE(sx9500_samp_freq_table); i++)
 414                 if (val == sx9500_samp_freq_table[i].val &&
 415                     val2 == sx9500_samp_freq_table[i].val2)
 416                         break;
 417
 418         if (i == ARRAY_SIZE(sx9500_samp_freq_table))
 419                 return -EINVAL;
 420
 421         mutex_lock(&data->mutex);
 422
 423         ret = regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
 424                                  SX9500_SCAN_PERIOD_MASK,
 425                                  i << SX9500_SCAN_PERIOD_SHIFT);
 426
 427         mutex_unlock(&data->mutex);
 428
 429         return ret;
 430 }
 431
 432 static int sx9500_write_raw(struct iio_dev *indio_dev,
 433                             const struct iio_chan_spec *chan,
 434                             int val, int val2, long mask)
 435 {
 436         struct sx9500_data *data = iio_priv(indio_dev);
 437
 438         switch (chan->type) {
 439         case IIO_PROXIMITY:
 440                 switch (mask) {
 441                 case IIO_CHAN_INFO_SAMP_FREQ:
 442                         return sx9500_set_samp_freq(data, val, val2);
 443                 default:
 444                         return -EINVAL;
 445                 }
 446         default:
 447                 return -EINVAL;
 448         }
 449 }
 450
 451 static irqreturn_t sx9500_irq_handler(int irq, void *private)
 452 {
 453         struct iio_dev *indio_dev = private;
 454         struct sx9500_data *data = iio_priv(indio_dev);
 455
 456         if (data->trigger_enabled)
 457                 iio_trigger_poll(data->trig);
 458
 459         /*
 460          * Even if no event is enabled, we need to wake the thread to
 461          * clear the interrupt state by reading SX9500_REG_IRQ_SRC.  It
 462          * is not possible to do that here because regmap_read takes a
 463          * mutex.
 464          */
 465         return IRQ_WAKE_THREAD;
 466 }
 467
 468 static void sx9500_push_events(struct iio_dev *indio_dev)
 469 {
 470         int ret;
 471         unsigned int val, chan;
 472         struct sx9500_data *data = iio_priv(indio_dev);
 473
 474         ret = regmap_read(data->regmap, SX9500_REG_STAT, &val);
 475         if (ret < 0) {
 476                 dev_err(&data->client->dev, "i2c transfer error in irq\n");
 477                 return;
 478         }
 479
 480         val >>= SX9500_PROXSTAT_SHIFT;
 481         for (chan = 0; chan < SX9500_NUM_CHANNELS; chan++) {
 482                 int dir;
 483                 u64 ev;
 484                 bool new_prox = val & BIT(chan);
 485
 486                 if (!data->event_enabled[chan])
 487                         continue;
 488                 if (new_prox == data->prox_stat[chan])
 489                         /* No change on this channel. */
 490                         continue;
 491
 492                 dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
 493                 ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
 494                                           IIO_EV_TYPE_THRESH, dir);
 495                 iio_push_event(indio_dev, ev, iio_get_time_ns(indio_dev));
 496                 data->prox_stat[chan] = new_prox;
 497         }
 498 }
 499
 500 static irqreturn_t sx9500_irq_thread_handler(int irq, void *private)
 501 {
 502         struct iio_dev *indio_dev = private;
 503         struct sx9500_data *data = iio_priv(indio_dev);
 504         int ret;
 505         unsigned int val;
 506
 507         mutex_lock(&data->mutex);
 508
 509         ret = regmap_read(data->regmap, SX9500_REG_IRQ_SRC, &val);
 510         if (ret < 0) {
 511                 dev_err(&data->client->dev, "i2c transfer error in irq\n");
 512                 goto out;
 513         }
 514
 515         if (val & (SX9500_CLOSE_IRQ | SX9500_FAR_IRQ))
 516                 sx9500_push_events(indio_dev);
 517
 518         if (val & SX9500_CONVDONE_IRQ)
 519                 complete_all(&data->completion);
 520
 521 out:
 522         mutex_unlock(&data->mutex);
 523
 524         return IRQ_HANDLED;
 525 }
 526
 527 static int sx9500_read_event_config(struct iio_dev *indio_dev,
 528                                     const struct iio_chan_spec *chan,
 529                                     enum iio_event_type type,
 530                                     enum iio_event_direction dir)
 531 {
 532         struct sx9500_data *data = iio_priv(indio_dev);
 533
 534         if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
 535             dir != IIO_EV_DIR_EITHER)
 536                 return -EINVAL;
 537
 538         return data->event_enabled[chan->channel];
 539 }
 540
 541 static int sx9500_write_event_config(struct iio_dev *indio_dev,
 542                                      const struct iio_chan_spec *chan,
 543                                      enum iio_event_type type,
 544                                      enum iio_event_direction dir,
 545                                      int state)
 546 {
 547         struct sx9500_data *data = iio_priv(indio_dev);
 548         int ret;
 549
 550         if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
 551             dir != IIO_EV_DIR_EITHER)
 552                 return -EINVAL;
 553
 554         mutex_lock(&data->mutex);
 555
 556         if (state == 1) {
 557                 ret = sx9500_inc_chan_users(data, chan->channel);
 558                 if (ret < 0)
 559                         goto out_unlock;
 560                 ret = sx9500_inc_close_far_users(data);
 561                 if (ret < 0)
 562                         goto out_undo_chan;
 563         } else {
 564                 ret = sx9500_dec_chan_users(data, chan->channel);
 565                 if (ret < 0)
 566                         goto out_unlock;
 567                 ret = sx9500_dec_close_far_users(data);
 568                 if (ret < 0)
 569                         goto out_undo_chan;
 570         }
 571
 572         data->event_enabled[chan->channel] = state;
 573         goto out_unlock;
 574
 575 out_undo_chan:
 576         if (state == 1)
 577                 sx9500_dec_chan_users(data, chan->channel);
 578         else
 579                 sx9500_inc_chan_users(data, chan->channel);
 580 out_unlock:
 581         mutex_unlock(&data->mutex);
 582         return ret;
 583 }
 584
 585 static int sx9500_update_scan_mode(struct iio_dev *indio_dev,
 586                                    const unsigned long *scan_mask)
 587 {
 588         struct sx9500_data *data = iio_priv(indio_dev);
 589
 590         mutex_lock(&data->mutex);
 591         kfree(data->buffer);
 592         data->buffer = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
 593         mutex_unlock(&data->mutex);
 594
 595         if (data->buffer == NULL)
 596                 return -ENOMEM;
 597
 598         return 0;
 599 }
 600
 601 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
 602         "2.500000 3.333333 5 6.666666 8.333333 11.111111 16.666666 33.333333");
 603
 604 static struct attribute *sx9500_attributes[] = {
 605         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 606         NULL,
 607 };
 608
 609 static const struct attribute_group sx9500_attribute_group = {
 610         .attrs = sx9500_attributes,
 611 };
 612
 613 static const struct iio_info sx9500_info = {
 614         .driver_module = THIS_MODULE,
 615         .attrs = &sx9500_attribute_group,
 616         .read_raw = &sx9500_read_raw,
 617         .write_raw = &sx9500_write_raw,
 618         .read_event_config = &sx9500_read_event_config,
 619         .write_event_config = &sx9500_write_event_config,
 620         .update_scan_mode = &sx9500_update_scan_mode,
 621 };
 622
 623 static int sx9500_set_trigger_state(struct iio_trigger *trig,
 624                                     bool state)
 625 {
 626         struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
 627         struct sx9500_data *data = iio_priv(indio_dev);
 628         int ret;
 629
 630         mutex_lock(&data->mutex);
 631
 632         if (state)
 633                 ret = sx9500_inc_data_rdy_users(data);
 634         else
 635                 ret = sx9500_dec_data_rdy_users(data);
 636         if (ret < 0)
 637                 goto out;
 638
 639         data->trigger_enabled = state;
 640
 641 out:
 642         mutex_unlock(&data->mutex);
 643
 644         return ret;
 645 }
 646
 647 static const struct iio_trigger_ops sx9500_trigger_ops = {
 648         .set_trigger_state = sx9500_set_trigger_state,
 649         .owner = THIS_MODULE,
 650 };
 651
 652 static irqreturn_t sx9500_trigger_handler(int irq, void *private)
 653 {
 654         struct iio_poll_func *pf = private;
 655         struct iio_dev *indio_dev = pf->indio_dev;
 656         struct sx9500_data *data = iio_priv(indio_dev);
 657         int val, bit, ret, i = 0;
 658
 659         mutex_lock(&data->mutex);
 660
 661         for_each_set_bit(bit, indio_dev->active_scan_mask,
 662                          indio_dev->masklength) {
 663                 ret = sx9500_read_prox_data(data, &indio_dev->channels[bit],
 664                                             &val);
 665                 if (ret < 0)
 666                         goto out;
 667
 668                 data->buffer[i++] = val;
 669         }
 670
 671         iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 672                                            iio_get_time_ns(indio_dev));
 673
 674 out:
 675         mutex_unlock(&data->mutex);
 676
 677         iio_trigger_notify_done(indio_dev->trig);
 678
 679         return IRQ_HANDLED;
 680 }
 681
 682 static int sx9500_buffer_preenable(struct iio_dev *indio_dev)
 683 {
 684         struct sx9500_data *data = iio_priv(indio_dev);
 685         int ret = 0, i;
 686
 687         mutex_lock(&data->mutex);
 688
 689         for (i = 0; i < SX9500_NUM_CHANNELS; i++)
 690                 if (test_bit(i, indio_dev->active_scan_mask)) {
 691                         ret = sx9500_inc_chan_users(data, i);
 692                         if (ret)
 693                                 break;
 694                 }
 695
 696         if (ret)
 697                 for (i = i - 1; i >= 0; i--)
 698                         if (test_bit(i, indio_dev->active_scan_mask))
 699                                 sx9500_dec_chan_users(data, i);
 700
 701         mutex_unlock(&data->mutex);
 702
 703         return ret;
 704 }
 705
 706 static int sx9500_buffer_predisable(struct iio_dev *indio_dev)
 707 {
 708         struct sx9500_data *data = iio_priv(indio_dev);
 709         int ret = 0, i;
 710
 711         iio_triggered_buffer_predisable(indio_dev);
 712
 713         mutex_lock(&data->mutex);
 714
 715         for (i = 0; i < SX9500_NUM_CHANNELS; i++)
 716                 if (test_bit(i, indio_dev->active_scan_mask)) {
 717                         ret = sx9500_dec_chan_users(data, i);
 718                         if (ret)
 719                                 break;
 720                 }
 721
 722         if (ret)
 723                 for (i = i - 1; i >= 0; i--)
 724                         if (test_bit(i, indio_dev->active_scan_mask))
 725                                 sx9500_inc_chan_users(data, i);
 726
 727         mutex_unlock(&data->mutex);
 728
 729         return ret;
 730 }
 731
 732 static const struct iio_buffer_setup_ops sx9500_buffer_setup_ops = {
 733         .preenable = sx9500_buffer_preenable,
 734         .postenable = iio_triggered_buffer_postenable,
 735         .predisable = sx9500_buffer_predisable,
 736 };
 737
 738 struct sx9500_reg_default {
 739         u8 reg;
 740         u8 def;
 741 };
 742
 743 static const struct sx9500_reg_default sx9500_default_regs[] = {
 744         {
 745                 .reg = SX9500_REG_PROX_CTRL1,
 746                 /* Shield enabled, small range. */
 747                 .def = 0x43,
 748         },
 749         {
 750                 .reg = SX9500_REG_PROX_CTRL2,
 751                 /* x8 gain, 167kHz frequency, finest resolution. */
 752                 .def = 0x77,
 753         },
 754         {
 755                 .reg = SX9500_REG_PROX_CTRL3,
 756                 /* Doze enabled, 2x scan period doze, no raw filter. */
 757                 .def = 0x40,
 758         },
 759         {
 760                 .reg = SX9500_REG_PROX_CTRL4,
 761                 /* Average threshold. */
 762                 .def = 0x30,
 763         },
 764         {
 765                 .reg = SX9500_REG_PROX_CTRL5,
 766                 /*
 767                  * Debouncer off, lowest average negative filter,
 768                  * highest average postive filter.
 769                  */
 770                 .def = 0x0f,
 771         },
 772         {
 773                 .reg = SX9500_REG_PROX_CTRL6,
 774                 /* Proximity detection threshold: 280 */
 775                 .def = 0x0e,
 776         },
 777         {
 778                 .reg = SX9500_REG_PROX_CTRL7,
 779                 /*
 780                  * No automatic compensation, compensate each pin
 781                  * independently, proximity hysteresis: 32, close
 782                  * debouncer off, far debouncer off.
 783                  */
 784                 .def = 0x00,
 785         },
 786         {
 787                 .reg = SX9500_REG_PROX_CTRL8,
 788                 /* No stuck timeout, no periodic compensation. */
 789                 .def = 0x00,
 790         },
 791         {
 792                 .reg = SX9500_REG_PROX_CTRL0,
 793                 /* Scan period: 30ms, all sensors disabled. */
 794                 .def = 0x00,
 795         },
 796 };
 797
 798 /* Activate all channels and perform an initial compensation. */
 799 static int sx9500_init_compensation(struct iio_dev *indio_dev)
 800 {
 801         struct sx9500_data *data = iio_priv(indio_dev);
 802         int i, ret;
 803         unsigned int val;
 804
 805         ret = regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
 806                                  SX9500_CHAN_MASK, SX9500_CHAN_MASK);
 807         if (ret < 0)
 808                 return ret;
 809
 810         for (i = 10; i >= 0; i--) {
 811                 usleep_range(10000, 20000);
 812                 ret = regmap_read(data->regmap, SX9500_REG_STAT, &val);
 813                 if (ret < 0)
 814                         goto out;
 815                 if (!(val & SX9500_COMPSTAT_MASK))
 816                         break;
 817         }
 818
 819         if (i < 0) {
 820                 dev_err(&data->client->dev, "initial compensation timed out");
 821                 ret = -ETIMEDOUT;
 822         }
 823
 824 out:
 825         regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
 826                            SX9500_CHAN_MASK, 0);
 827         return ret;
 828 }
 829
 830 static int sx9500_init_device(struct iio_dev *indio_dev)
 831 {
 832         struct sx9500_data *data = iio_priv(indio_dev);
 833         int ret, i;
 834         unsigned int val;
 835
 836         if (data->gpiod_rst) {
 837                 gpiod_set_value_cansleep(data->gpiod_rst, 0);
 838                 usleep_range(1000, 2000);
 839                 gpiod_set_value_cansleep(data->gpiod_rst, 1);
 840                 usleep_range(1000, 2000);
 841         }
 842
 843         ret = regmap_write(data->regmap, SX9500_REG_IRQ_MSK, 0);
 844         if (ret < 0)
 845                 return ret;
 846
 847         ret = regmap_write(data->regmap, SX9500_REG_RESET,
 848                            SX9500_SOFT_RESET);
 849         if (ret < 0)
 850                 return ret;
 851
 852         ret = regmap_read(data->regmap, SX9500_REG_IRQ_SRC, &val);
 853         if (ret < 0)
 854                 return ret;
 855
 856         for (i = 0; i < ARRAY_SIZE(sx9500_default_regs); i++) {
 857                 ret = regmap_write(data->regmap,
 858                                    sx9500_default_regs[i].reg,
 859                                    sx9500_default_regs[i].def);
 860                 if (ret < 0)
 861                         return ret;
 862         }
 863
 864         return sx9500_init_compensation(indio_dev);
 865 }
 866
 867 static void sx9500_gpio_probe(struct i2c_client *client,
 868                               struct sx9500_data *data)
 869 {
 870         struct device *dev;
 871
 872         if (!client)
 873                 return;
 874
 875         dev = &client->dev;
 876
 877         data->gpiod_rst = devm_gpiod_get_index(dev, SX9500_GPIO_RESET,
 878                                                0, GPIOD_OUT_HIGH);
 879         if (IS_ERR(data->gpiod_rst)) {
 880                 dev_warn(dev, "gpio get reset pin failed\n");
 881                 data->gpiod_rst = NULL;
 882         }
 883 }
 884
 885 static int sx9500_probe(struct i2c_client *client,
 886                         const struct i2c_device_id *id)
 887 {
 888         int ret;
 889         struct iio_dev *indio_dev;
 890         struct sx9500_data *data;
 891
 892         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 893         if (indio_dev == NULL)
 894                 return -ENOMEM;
 895
 896         data = iio_priv(indio_dev);
 897         data->client = client;
 898         mutex_init(&data->mutex);
 899         init_completion(&data->completion);
 900         data->trigger_enabled = false;
 901
 902         data->regmap = devm_regmap_init_i2c(client, &sx9500_regmap_config);
 903         if (IS_ERR(data->regmap))
 904                 return PTR_ERR(data->regmap);
 905
 906         indio_dev->dev.parent = &client->dev;
 907         indio_dev->name = SX9500_DRIVER_NAME;
 908         indio_dev->channels = sx9500_channels;
 909         indio_dev->num_channels = ARRAY_SIZE(sx9500_channels);
 910         indio_dev->info = &sx9500_info;
 911         indio_dev->modes = INDIO_DIRECT_MODE;
 912         i2c_set_clientdata(client, indio_dev);
 913
 914         sx9500_gpio_probe(client, data);
 915
 916         ret = sx9500_init_device(indio_dev);
 917         if (ret < 0)
 918                 return ret;
 919
 920         if (client->irq <= 0)
 921                 dev_warn(&client->dev, "no valid irq found\n");
 922         else {
 923                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 924                                 sx9500_irq_handler, sx9500_irq_thread_handler,
 925                                 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 926                                 SX9500_IRQ_NAME, indio_dev);
 927                 if (ret < 0)
 928                         return ret;
 929
 930                 data->trig = devm_iio_trigger_alloc(&client->dev,
 931                                 "%s-dev%d", indio_dev->name, indio_dev->id);
 932                 if (!data->trig)
 933                         return -ENOMEM;
 934
 935                 data->trig->dev.parent = &client->dev;
 936                 data->trig->ops = &sx9500_trigger_ops;
 937                 iio_trigger_set_drvdata(data->trig, indio_dev);
 938
 939                 ret = iio_trigger_register(data->trig);
 940                 if (ret)
 941                         return ret;
 942         }
 943
 944         ret = iio_triggered_buffer_setup(indio_dev, NULL,
 945                                          sx9500_trigger_handler,
 946                                          &sx9500_buffer_setup_ops);
 947         if (ret < 0)
 948                 goto out_trigger_unregister;
 949
 950         ret = iio_device_register(indio_dev);
 951         if (ret < 0)
 952                 goto out_buffer_cleanup;
 953
 954         return 0;
 955
 956 out_buffer_cleanup:
 957         iio_triggered_buffer_cleanup(indio_dev);
 958 out_trigger_unregister:
 959         if (client->irq > 0)
 960                 iio_trigger_unregister(data->trig);
 961
 962         return ret;
 963 }
 964
 965 static int sx9500_remove(struct i2c_client *client)
 966 {
 967         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 968         struct sx9500_data *data = iio_priv(indio_dev);
 969
 970         iio_device_unregister(indio_dev);
 971         iio_triggered_buffer_cleanup(indio_dev);
 972         if (client->irq > 0)
 973                 iio_trigger_unregister(data->trig);
 974         kfree(data->buffer);
 975
 976         return 0;
 977 }
 978
 979 #ifdef CONFIG_PM_SLEEP
 980 static int sx9500_suspend(struct device *dev)
 981 {
 982         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 983         struct sx9500_data *data = iio_priv(indio_dev);
 984         int ret;
 985
 986         mutex_lock(&data->mutex);
 987         ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0,
 988                           &data->suspend_ctrl0);
 989         if (ret < 0)
 990                 goto out;
 991
 992         /*
 993          * Scan period doesn't matter because when all the sensors are
 994          * deactivated the device is in sleep mode.
 995          */
 996         ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0, 0);
 997
 998 out:
 999         mutex_unlock(&data->mutex);
1000         return ret;
1001 }
1002
1003 static int sx9500_resume(struct device *dev)
1004 {
1005         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1006         struct sx9500_data *data = iio_priv(indio_dev);
1007         int ret;
1008
1009         mutex_lock(&data->mutex);
1010         ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0,
1011                            data->suspend_ctrl0);
1012         mutex_unlock(&data->mutex);
1013
1014         return ret;
1015 }
1016 #endif /* CONFIG_PM_SLEEP */
1017
1018 static const struct dev_pm_ops sx9500_pm_ops = {
1019         SET_SYSTEM_SLEEP_PM_OPS(sx9500_suspend, sx9500_resume)
1020 };
1021
1022 static const struct acpi_device_id sx9500_acpi_match[] = {
1023         {"SSX9500", 0},
1024         { },
1025 };
1026 MODULE_DEVICE_TABLE(acpi, sx9500_acpi_match);
1027
1028 static const struct i2c_device_id sx9500_id[] = {
1029         {"sx9500", 0},
1030         { },
1031 };
1032 MODULE_DEVICE_TABLE(i2c, sx9500_id);
1033
1034 static struct i2c_driver sx9500_driver = {
1035         .driver = {
1036                 .name   = SX9500_DRIVER_NAME,
1037                 .acpi_match_table = ACPI_PTR(sx9500_acpi_match),
1038                 .pm = &sx9500_pm_ops,
1039         },
1040         .probe          = sx9500_probe,
1041         .remove         = sx9500_remove,
1042         .id_table       = sx9500_id,
1043 };
1044 module_i2c_driver(sx9500_driver);
1045
1046 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
1047 MODULE_DESCRIPTION("Driver for Semtech SX9500 proximity sensor");
1048 MODULE_LICENSE("GPL v2");