linux/drivers/iio/proximity/sx9500.c
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   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/* Register definitions. */
  36#define SX9500_REG_IRQ_SRC              0x00
  37#define SX9500_REG_STAT                 0x01
  38#define SX9500_REG_IRQ_MSK              0x03
  39
  40#define SX9500_REG_PROX_CTRL0           0x06
  41#define SX9500_REG_PROX_CTRL1           0x07
  42#define SX9500_REG_PROX_CTRL2           0x08
  43#define SX9500_REG_PROX_CTRL3           0x09
  44#define SX9500_REG_PROX_CTRL4           0x0a
  45#define SX9500_REG_PROX_CTRL5           0x0b
  46#define SX9500_REG_PROX_CTRL6           0x0c
  47#define SX9500_REG_PROX_CTRL7           0x0d
  48#define SX9500_REG_PROX_CTRL8           0x0e
  49
  50#define SX9500_REG_SENSOR_SEL           0x20
  51#define SX9500_REG_USE_MSB              0x21
  52#define SX9500_REG_USE_LSB              0x22
  53#define SX9500_REG_AVG_MSB              0x23
  54#define SX9500_REG_AVG_LSB              0x24
  55#define SX9500_REG_DIFF_MSB             0x25
  56#define SX9500_REG_DIFF_LSB             0x26
  57#define SX9500_REG_OFFSET_MSB           0x27
  58#define SX9500_REG_OFFSET_LSB           0x28
  59
  60#define SX9500_REG_RESET                0x7f
  61
  62/* Write this to REG_RESET to do a soft reset. */
  63#define SX9500_SOFT_RESET               0xde
  64
  65#define SX9500_SCAN_PERIOD_MASK         GENMASK(6, 4)
  66#define SX9500_SCAN_PERIOD_SHIFT        4
  67
  68/*
  69 * These serve for identifying IRQ source in the IRQ_SRC register, and
  70 * also for masking the IRQs in the IRQ_MSK register.
  71 */
  72#define SX9500_CLOSE_IRQ                BIT(6)
  73#define SX9500_FAR_IRQ                  BIT(5)
  74#define SX9500_CONVDONE_IRQ             BIT(3)
  75
  76#define SX9500_PROXSTAT_SHIFT           4
  77#define SX9500_COMPSTAT_MASK            GENMASK(3, 0)
  78
  79#define SX9500_NUM_CHANNELS             4
  80#define SX9500_CHAN_MASK                GENMASK(SX9500_NUM_CHANNELS - 1, 0)
  81
  82struct sx9500_data {
  83        struct mutex mutex;
  84        struct i2c_client *client;
  85        struct iio_trigger *trig;
  86        struct regmap *regmap;
  87        struct gpio_desc *gpiod_rst;
  88        /*
  89         * Last reading of the proximity status for each channel.  We
  90         * only send an event to user space when this changes.
  91         */
  92        bool prox_stat[SX9500_NUM_CHANNELS];
  93        bool event_enabled[SX9500_NUM_CHANNELS];
  94        bool trigger_enabled;
  95        u16 *buffer;
  96        /* Remember enabled channels and sample rate during suspend. */
  97        unsigned int suspend_ctrl0;
  98        struct completion completion;
  99        int data_rdy_users, close_far_users;
 100        int channel_users[SX9500_NUM_CHANNELS];
 101};
 102
 103static const struct iio_event_spec sx9500_events[] = {
 104        {
 105                .type = IIO_EV_TYPE_THRESH,
 106                .dir = IIO_EV_DIR_EITHER,
 107                .mask_separate = BIT(IIO_EV_INFO_ENABLE),
 108        },
 109};
 110
 111#define SX9500_CHANNEL(idx)                                     \
 112        {                                                       \
 113                .type = IIO_PROXIMITY,                          \
 114                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
 115                .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
 116                .indexed = 1,                                   \
 117                .channel = idx,                                 \
 118                .event_spec = sx9500_events,                    \
 119                .num_event_specs = ARRAY_SIZE(sx9500_events),   \
 120                .scan_index = idx,                              \
 121                .scan_type = {                                  \
 122                        .sign = 'u',                            \
 123                        .realbits = 16,                         \
 124                        .storagebits = 16,                      \
 125                        .shift = 0,                             \
 126                },                                              \
 127        }
 128
 129static const struct iio_chan_spec sx9500_channels[] = {
 130        SX9500_CHANNEL(0),
 131        SX9500_CHANNEL(1),
 132        SX9500_CHANNEL(2),
 133        SX9500_CHANNEL(3),
 134        IIO_CHAN_SOFT_TIMESTAMP(4),
 135};
 136
 137static const struct {
 138        int val;
 139        int val2;
 140} sx9500_samp_freq_table[] = {
 141        {33, 333333},
 142        {16, 666666},
 143        {11, 111111},
 144        {8, 333333},
 145        {6, 666666},
 146        {5, 0},
 147        {3, 333333},
 148        {2, 500000},
 149};
 150
 151static const unsigned int sx9500_scan_period_table[] = {
 152        30, 60, 90, 120, 150, 200, 300, 400,
 153};
 154
 155static const struct regmap_range sx9500_writable_reg_ranges[] = {
 156        regmap_reg_range(SX9500_REG_IRQ_MSK, SX9500_REG_IRQ_MSK),
 157        regmap_reg_range(SX9500_REG_PROX_CTRL0, SX9500_REG_PROX_CTRL8),
 158        regmap_reg_range(SX9500_REG_SENSOR_SEL, SX9500_REG_SENSOR_SEL),
 159        regmap_reg_range(SX9500_REG_OFFSET_MSB, SX9500_REG_OFFSET_LSB),
 160        regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
 161};
 162
 163static const struct regmap_access_table sx9500_writeable_regs = {
 164        .yes_ranges = sx9500_writable_reg_ranges,
 165        .n_yes_ranges = ARRAY_SIZE(sx9500_writable_reg_ranges),
 166};
 167
 168/*
 169 * All allocated registers are readable, so we just list unallocated
 170 * ones.
 171 */
 172static const struct regmap_range sx9500_non_readable_reg_ranges[] = {
 173        regmap_reg_range(SX9500_REG_STAT + 1, SX9500_REG_STAT + 1),
 174        regmap_reg_range(SX9500_REG_IRQ_MSK + 1, SX9500_REG_PROX_CTRL0 - 1),
 175        regmap_reg_range(SX9500_REG_PROX_CTRL8 + 1, SX9500_REG_SENSOR_SEL - 1),
 176        regmap_reg_range(SX9500_REG_OFFSET_LSB + 1, SX9500_REG_RESET - 1),
 177};
 178
 179static const struct regmap_access_table sx9500_readable_regs = {
 180        .no_ranges = sx9500_non_readable_reg_ranges,
 181        .n_no_ranges = ARRAY_SIZE(sx9500_non_readable_reg_ranges),
 182};
 183
 184static const struct regmap_range sx9500_volatile_reg_ranges[] = {
 185        regmap_reg_range(SX9500_REG_IRQ_SRC, SX9500_REG_STAT),
 186        regmap_reg_range(SX9500_REG_USE_MSB, SX9500_REG_OFFSET_LSB),
 187        regmap_reg_range(SX9500_REG_RESET, SX9500_REG_RESET),
 188};
 189
 190static const struct regmap_access_table sx9500_volatile_regs = {
 191        .yes_ranges = sx9500_volatile_reg_ranges,
 192        .n_yes_ranges = ARRAY_SIZE(sx9500_volatile_reg_ranges),
 193};
 194
 195static const struct regmap_config sx9500_regmap_config = {
 196        .reg_bits = 8,
 197        .val_bits = 8,
 198
 199        .max_register = SX9500_REG_RESET,
 200        .cache_type = REGCACHE_RBTREE,
 201
 202        .wr_table = &sx9500_writeable_regs,
 203        .rd_table = &sx9500_readable_regs,
 204        .volatile_table = &sx9500_volatile_regs,
 205};
 206
 207static int sx9500_inc_users(struct sx9500_data *data, int *counter,
 208                            unsigned int reg, unsigned int bitmask)
 209{
 210        (*counter)++;
 211        if (*counter != 1)
 212                /* Bit is already active, nothing to do. */
 213                return 0;
 214
 215        return regmap_update_bits(data->regmap, reg, bitmask, bitmask);
 216}
 217
 218static int sx9500_dec_users(struct sx9500_data *data, int *counter,
 219                            unsigned int reg, unsigned int bitmask)
 220{
 221        (*counter)--;
 222        if (*counter != 0)
 223                /* There are more users, do not deactivate. */
 224                return 0;
 225
 226        return regmap_update_bits(data->regmap, reg, bitmask, 0);
 227}
 228
 229static int sx9500_inc_chan_users(struct sx9500_data *data, int chan)
 230{
 231        return sx9500_inc_users(data, &data->channel_users[chan],
 232                                SX9500_REG_PROX_CTRL0, BIT(chan));
 233}
 234
 235static int sx9500_dec_chan_users(struct sx9500_data *data, int chan)
 236{
 237        return sx9500_dec_users(data, &data->channel_users[chan],
 238                                SX9500_REG_PROX_CTRL0, BIT(chan));
 239}
 240
 241static int sx9500_inc_data_rdy_users(struct sx9500_data *data)
 242{
 243        return sx9500_inc_users(data, &data->data_rdy_users,
 244                                SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
 245}
 246
 247static int sx9500_dec_data_rdy_users(struct sx9500_data *data)
 248{
 249        return sx9500_dec_users(data, &data->data_rdy_users,
 250                                SX9500_REG_IRQ_MSK, SX9500_CONVDONE_IRQ);
 251}
 252
 253static int sx9500_inc_close_far_users(struct sx9500_data *data)
 254{
 255        return sx9500_inc_users(data, &data->close_far_users,
 256                                SX9500_REG_IRQ_MSK,
 257                                SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
 258}
 259
 260static int sx9500_dec_close_far_users(struct sx9500_data *data)
 261{
 262        return sx9500_dec_users(data, &data->close_far_users,
 263                                SX9500_REG_IRQ_MSK,
 264                                SX9500_CLOSE_IRQ | SX9500_FAR_IRQ);
 265}
 266
 267static int sx9500_read_prox_data(struct sx9500_data *data,
 268                                 const struct iio_chan_spec *chan,
 269                                 int *val)
 270{
 271        int ret;
 272        __be16 regval;
 273
 274        ret = regmap_write(data->regmap, SX9500_REG_SENSOR_SEL, chan->channel);
 275        if (ret < 0)
 276                return ret;
 277
 278        ret = regmap_bulk_read(data->regmap, SX9500_REG_USE_MSB, &regval, 2);
 279        if (ret < 0)
 280                return ret;
 281
 282        *val = be16_to_cpu(regval);
 283
 284        return IIO_VAL_INT;
 285}
 286
 287/*
 288 * If we have no interrupt support, we have to wait for a scan period
 289 * after enabling a channel to get a result.
 290 */
 291static int sx9500_wait_for_sample(struct sx9500_data *data)
 292{
 293        int ret;
 294        unsigned int val;
 295
 296        ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0, &val);
 297        if (ret < 0)
 298                return ret;
 299
 300        val = (val & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
 301
 302        msleep(sx9500_scan_period_table[val]);
 303
 304        return 0;
 305}
 306
 307static int sx9500_read_proximity(struct sx9500_data *data,
 308                                 const struct iio_chan_spec *chan,
 309                                 int *val)
 310{
 311        int ret;
 312
 313        mutex_lock(&data->mutex);
 314
 315        ret = sx9500_inc_chan_users(data, chan->channel);
 316        if (ret < 0)
 317                goto out;
 318
 319        ret = sx9500_inc_data_rdy_users(data);
 320        if (ret < 0)
 321                goto out_dec_chan;
 322
 323        mutex_unlock(&data->mutex);
 324
 325        if (data->client->irq > 0)
 326                ret = wait_for_completion_interruptible(&data->completion);
 327        else
 328                ret = sx9500_wait_for_sample(data);
 329
 330        mutex_lock(&data->mutex);
 331
 332        if (ret < 0)
 333                goto out_dec_data_rdy;
 334
 335        ret = sx9500_read_prox_data(data, chan, val);
 336        if (ret < 0)
 337                goto out_dec_data_rdy;
 338
 339        ret = sx9500_dec_data_rdy_users(data);
 340        if (ret < 0)
 341                goto out_dec_chan;
 342
 343        ret = sx9500_dec_chan_users(data, chan->channel);
 344        if (ret < 0)
 345                goto out;
 346
 347        ret = IIO_VAL_INT;
 348
 349        goto out;
 350
 351out_dec_data_rdy:
 352        sx9500_dec_data_rdy_users(data);
 353out_dec_chan:
 354        sx9500_dec_chan_users(data, chan->channel);
 355out:
 356        mutex_unlock(&data->mutex);
 357        reinit_completion(&data->completion);
 358
 359        return ret;
 360}
 361
 362static int sx9500_read_samp_freq(struct sx9500_data *data,
 363                                 int *val, int *val2)
 364{
 365        int ret;
 366        unsigned int regval;
 367
 368        mutex_lock(&data->mutex);
 369        ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0, &regval);
 370        mutex_unlock(&data->mutex);
 371
 372        if (ret < 0)
 373                return ret;
 374
 375        regval = (regval & SX9500_SCAN_PERIOD_MASK) >> SX9500_SCAN_PERIOD_SHIFT;
 376        *val = sx9500_samp_freq_table[regval].val;
 377        *val2 = sx9500_samp_freq_table[regval].val2;
 378
 379        return IIO_VAL_INT_PLUS_MICRO;
 380}
 381
 382static int sx9500_read_raw(struct iio_dev *indio_dev,
 383                           const struct iio_chan_spec *chan,
 384                           int *val, int *val2, long mask)
 385{
 386        struct sx9500_data *data = iio_priv(indio_dev);
 387        int ret;
 388
 389        switch (chan->type) {
 390        case IIO_PROXIMITY:
 391                switch (mask) {
 392                case IIO_CHAN_INFO_RAW:
 393                        ret = iio_device_claim_direct_mode(indio_dev);
 394                        if (ret)
 395                                return ret;
 396                        ret = sx9500_read_proximity(data, chan, val);
 397                        iio_device_release_direct_mode(indio_dev);
 398                        return ret;
 399                case IIO_CHAN_INFO_SAMP_FREQ:
 400                        return sx9500_read_samp_freq(data, val, val2);
 401                default:
 402                        return -EINVAL;
 403                }
 404        default:
 405                return -EINVAL;
 406        }
 407}
 408
 409static int sx9500_set_samp_freq(struct sx9500_data *data,
 410                                int val, int val2)
 411{
 412        int i, ret;
 413
 414        for (i = 0; i < ARRAY_SIZE(sx9500_samp_freq_table); i++)
 415                if (val == sx9500_samp_freq_table[i].val &&
 416                    val2 == sx9500_samp_freq_table[i].val2)
 417                        break;
 418
 419        if (i == ARRAY_SIZE(sx9500_samp_freq_table))
 420                return -EINVAL;
 421
 422        mutex_lock(&data->mutex);
 423
 424        ret = regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
 425                                 SX9500_SCAN_PERIOD_MASK,
 426                                 i << SX9500_SCAN_PERIOD_SHIFT);
 427
 428        mutex_unlock(&data->mutex);
 429
 430        return ret;
 431}
 432
 433static int sx9500_write_raw(struct iio_dev *indio_dev,
 434                            const struct iio_chan_spec *chan,
 435                            int val, int val2, long mask)
 436{
 437        struct sx9500_data *data = iio_priv(indio_dev);
 438
 439        switch (chan->type) {
 440        case IIO_PROXIMITY:
 441                switch (mask) {
 442                case IIO_CHAN_INFO_SAMP_FREQ:
 443                        return sx9500_set_samp_freq(data, val, val2);
 444                default:
 445                        return -EINVAL;
 446                }
 447        default:
 448                return -EINVAL;
 449        }
 450}
 451
 452static irqreturn_t sx9500_irq_handler(int irq, void *private)
 453{
 454        struct iio_dev *indio_dev = private;
 455        struct sx9500_data *data = iio_priv(indio_dev);
 456
 457        if (data->trigger_enabled)
 458                iio_trigger_poll(data->trig);
 459
 460        /*
 461         * Even if no event is enabled, we need to wake the thread to
 462         * clear the interrupt state by reading SX9500_REG_IRQ_SRC.  It
 463         * is not possible to do that here because regmap_read takes a
 464         * mutex.
 465         */
 466        return IRQ_WAKE_THREAD;
 467}
 468
 469static void sx9500_push_events(struct iio_dev *indio_dev)
 470{
 471        int ret;
 472        unsigned int val, chan;
 473        struct sx9500_data *data = iio_priv(indio_dev);
 474
 475        ret = regmap_read(data->regmap, SX9500_REG_STAT, &val);
 476        if (ret < 0) {
 477                dev_err(&data->client->dev, "i2c transfer error in irq\n");
 478                return;
 479        }
 480
 481        val >>= SX9500_PROXSTAT_SHIFT;
 482        for (chan = 0; chan < SX9500_NUM_CHANNELS; chan++) {
 483                int dir;
 484                u64 ev;
 485                bool new_prox = val & BIT(chan);
 486
 487                if (!data->event_enabled[chan])
 488                        continue;
 489                if (new_prox == data->prox_stat[chan])
 490                        /* No change on this channel. */
 491                        continue;
 492
 493                dir = new_prox ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
 494                ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
 495                                          IIO_EV_TYPE_THRESH, dir);
 496                iio_push_event(indio_dev, ev, iio_get_time_ns(indio_dev));
 497                data->prox_stat[chan] = new_prox;
 498        }
 499}
 500
 501static irqreturn_t sx9500_irq_thread_handler(int irq, void *private)
 502{
 503        struct iio_dev *indio_dev = private;
 504        struct sx9500_data *data = iio_priv(indio_dev);
 505        int ret;
 506        unsigned int val;
 507
 508        mutex_lock(&data->mutex);
 509
 510        ret = regmap_read(data->regmap, SX9500_REG_IRQ_SRC, &val);
 511        if (ret < 0) {
 512                dev_err(&data->client->dev, "i2c transfer error in irq\n");
 513                goto out;
 514        }
 515
 516        if (val & (SX9500_CLOSE_IRQ | SX9500_FAR_IRQ))
 517                sx9500_push_events(indio_dev);
 518
 519        if (val & SX9500_CONVDONE_IRQ)
 520                complete(&data->completion);
 521
 522out:
 523        mutex_unlock(&data->mutex);
 524
 525        return IRQ_HANDLED;
 526}
 527
 528static int sx9500_read_event_config(struct iio_dev *indio_dev,
 529                                    const struct iio_chan_spec *chan,
 530                                    enum iio_event_type type,
 531                                    enum iio_event_direction dir)
 532{
 533        struct sx9500_data *data = iio_priv(indio_dev);
 534
 535        if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
 536            dir != IIO_EV_DIR_EITHER)
 537                return -EINVAL;
 538
 539        return data->event_enabled[chan->channel];
 540}
 541
 542static int sx9500_write_event_config(struct iio_dev *indio_dev,
 543                                     const struct iio_chan_spec *chan,
 544                                     enum iio_event_type type,
 545                                     enum iio_event_direction dir,
 546                                     int state)
 547{
 548        struct sx9500_data *data = iio_priv(indio_dev);
 549        int ret;
 550
 551        if (chan->type != IIO_PROXIMITY || type != IIO_EV_TYPE_THRESH ||
 552            dir != IIO_EV_DIR_EITHER)
 553                return -EINVAL;
 554
 555        mutex_lock(&data->mutex);
 556
 557        if (state == 1) {
 558                ret = sx9500_inc_chan_users(data, chan->channel);
 559                if (ret < 0)
 560                        goto out_unlock;
 561                ret = sx9500_inc_close_far_users(data);
 562                if (ret < 0)
 563                        goto out_undo_chan;
 564        } else {
 565                ret = sx9500_dec_chan_users(data, chan->channel);
 566                if (ret < 0)
 567                        goto out_unlock;
 568                ret = sx9500_dec_close_far_users(data);
 569                if (ret < 0)
 570                        goto out_undo_chan;
 571        }
 572
 573        data->event_enabled[chan->channel] = state;
 574        goto out_unlock;
 575
 576out_undo_chan:
 577        if (state == 1)
 578                sx9500_dec_chan_users(data, chan->channel);
 579        else
 580                sx9500_inc_chan_users(data, chan->channel);
 581out_unlock:
 582        mutex_unlock(&data->mutex);
 583        return ret;
 584}
 585
 586static int sx9500_update_scan_mode(struct iio_dev *indio_dev,
 587                                   const unsigned long *scan_mask)
 588{
 589        struct sx9500_data *data = iio_priv(indio_dev);
 590
 591        mutex_lock(&data->mutex);
 592        kfree(data->buffer);
 593        data->buffer = kzalloc(indio_dev->scan_bytes, GFP_KERNEL);
 594        mutex_unlock(&data->mutex);
 595
 596        if (data->buffer == NULL)
 597                return -ENOMEM;
 598
 599        return 0;
 600}
 601
 602static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
 603        "2.500000 3.333333 5 6.666666 8.333333 11.111111 16.666666 33.333333");
 604
 605static struct attribute *sx9500_attributes[] = {
 606        &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 607        NULL,
 608};
 609
 610static const struct attribute_group sx9500_attribute_group = {
 611        .attrs = sx9500_attributes,
 612};
 613
 614static const struct iio_info sx9500_info = {
 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
 623static 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
 641out:
 642        mutex_unlock(&data->mutex);
 643
 644        return ret;
 645}
 646
 647static const struct iio_trigger_ops sx9500_trigger_ops = {
 648        .set_trigger_state = sx9500_set_trigger_state,
 649};
 650
 651static irqreturn_t sx9500_trigger_handler(int irq, void *private)
 652{
 653        struct iio_poll_func *pf = private;
 654        struct iio_dev *indio_dev = pf->indio_dev;
 655        struct sx9500_data *data = iio_priv(indio_dev);
 656        int val, bit, ret, i = 0;
 657
 658        mutex_lock(&data->mutex);
 659
 660        for_each_set_bit(bit, indio_dev->active_scan_mask,
 661                         indio_dev->masklength) {
 662                ret = sx9500_read_prox_data(data, &indio_dev->channels[bit],
 663                                            &val);
 664                if (ret < 0)
 665                        goto out;
 666
 667                data->buffer[i++] = val;
 668        }
 669
 670        iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 671                                           iio_get_time_ns(indio_dev));
 672
 673out:
 674        mutex_unlock(&data->mutex);
 675
 676        iio_trigger_notify_done(indio_dev->trig);
 677
 678        return IRQ_HANDLED;
 679}
 680
 681static int sx9500_buffer_preenable(struct iio_dev *indio_dev)
 682{
 683        struct sx9500_data *data = iio_priv(indio_dev);
 684        int ret = 0, i;
 685
 686        mutex_lock(&data->mutex);
 687
 688        for (i = 0; i < SX9500_NUM_CHANNELS; i++)
 689                if (test_bit(i, indio_dev->active_scan_mask)) {
 690                        ret = sx9500_inc_chan_users(data, i);
 691                        if (ret)
 692                                break;
 693                }
 694
 695        if (ret)
 696                for (i = i - 1; i >= 0; i--)
 697                        if (test_bit(i, indio_dev->active_scan_mask))
 698                                sx9500_dec_chan_users(data, i);
 699
 700        mutex_unlock(&data->mutex);
 701
 702        return ret;
 703}
 704
 705static int sx9500_buffer_predisable(struct iio_dev *indio_dev)
 706{
 707        struct sx9500_data *data = iio_priv(indio_dev);
 708        int ret = 0, i;
 709
 710        iio_triggered_buffer_predisable(indio_dev);
 711
 712        mutex_lock(&data->mutex);
 713
 714        for (i = 0; i < SX9500_NUM_CHANNELS; i++)
 715                if (test_bit(i, indio_dev->active_scan_mask)) {
 716                        ret = sx9500_dec_chan_users(data, i);
 717                        if (ret)
 718                                break;
 719                }
 720
 721        if (ret)
 722                for (i = i - 1; i >= 0; i--)
 723                        if (test_bit(i, indio_dev->active_scan_mask))
 724                                sx9500_inc_chan_users(data, i);
 725
 726        mutex_unlock(&data->mutex);
 727
 728        return ret;
 729}
 730
 731static const struct iio_buffer_setup_ops sx9500_buffer_setup_ops = {
 732        .preenable = sx9500_buffer_preenable,
 733        .postenable = iio_triggered_buffer_postenable,
 734        .predisable = sx9500_buffer_predisable,
 735};
 736
 737struct sx9500_reg_default {
 738        u8 reg;
 739        u8 def;
 740};
 741
 742static const struct sx9500_reg_default sx9500_default_regs[] = {
 743        {
 744                .reg = SX9500_REG_PROX_CTRL1,
 745                /* Shield enabled, small range. */
 746                .def = 0x43,
 747        },
 748        {
 749                .reg = SX9500_REG_PROX_CTRL2,
 750                /* x8 gain, 167kHz frequency, finest resolution. */
 751                .def = 0x77,
 752        },
 753        {
 754                .reg = SX9500_REG_PROX_CTRL3,
 755                /* Doze enabled, 2x scan period doze, no raw filter. */
 756                .def = 0x40,
 757        },
 758        {
 759                .reg = SX9500_REG_PROX_CTRL4,
 760                /* Average threshold. */
 761                .def = 0x30,
 762        },
 763        {
 764                .reg = SX9500_REG_PROX_CTRL5,
 765                /*
 766                 * Debouncer off, lowest average negative filter,
 767                 * highest average postive filter.
 768                 */
 769                .def = 0x0f,
 770        },
 771        {
 772                .reg = SX9500_REG_PROX_CTRL6,
 773                /* Proximity detection threshold: 280 */
 774                .def = 0x0e,
 775        },
 776        {
 777                .reg = SX9500_REG_PROX_CTRL7,
 778                /*
 779                 * No automatic compensation, compensate each pin
 780                 * independently, proximity hysteresis: 32, close
 781                 * debouncer off, far debouncer off.
 782                 */
 783                .def = 0x00,
 784        },
 785        {
 786                .reg = SX9500_REG_PROX_CTRL8,
 787                /* No stuck timeout, no periodic compensation. */
 788                .def = 0x00,
 789        },
 790        {
 791                .reg = SX9500_REG_PROX_CTRL0,
 792                /* Scan period: 30ms, all sensors disabled. */
 793                .def = 0x00,
 794        },
 795};
 796
 797/* Activate all channels and perform an initial compensation. */
 798static int sx9500_init_compensation(struct iio_dev *indio_dev)
 799{
 800        struct sx9500_data *data = iio_priv(indio_dev);
 801        int i, ret;
 802        unsigned int val;
 803
 804        ret = regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
 805                                 SX9500_CHAN_MASK, SX9500_CHAN_MASK);
 806        if (ret < 0)
 807                return ret;
 808
 809        for (i = 10; i >= 0; i--) {
 810                usleep_range(10000, 20000);
 811                ret = regmap_read(data->regmap, SX9500_REG_STAT, &val);
 812                if (ret < 0)
 813                        goto out;
 814                if (!(val & SX9500_COMPSTAT_MASK))
 815                        break;
 816        }
 817
 818        if (i < 0) {
 819                dev_err(&data->client->dev, "initial compensation timed out");
 820                ret = -ETIMEDOUT;
 821        }
 822
 823out:
 824        regmap_update_bits(data->regmap, SX9500_REG_PROX_CTRL0,
 825                           SX9500_CHAN_MASK, 0);
 826        return ret;
 827}
 828
 829static int sx9500_init_device(struct iio_dev *indio_dev)
 830{
 831        struct sx9500_data *data = iio_priv(indio_dev);
 832        int ret, i;
 833        unsigned int val;
 834
 835        if (data->gpiod_rst) {
 836                gpiod_set_value_cansleep(data->gpiod_rst, 0);
 837                usleep_range(1000, 2000);
 838                gpiod_set_value_cansleep(data->gpiod_rst, 1);
 839                usleep_range(1000, 2000);
 840        }
 841
 842        ret = regmap_write(data->regmap, SX9500_REG_IRQ_MSK, 0);
 843        if (ret < 0)
 844                return ret;
 845
 846        ret = regmap_write(data->regmap, SX9500_REG_RESET,
 847                           SX9500_SOFT_RESET);
 848        if (ret < 0)
 849                return ret;
 850
 851        ret = regmap_read(data->regmap, SX9500_REG_IRQ_SRC, &val);
 852        if (ret < 0)
 853                return ret;
 854
 855        for (i = 0; i < ARRAY_SIZE(sx9500_default_regs); i++) {
 856                ret = regmap_write(data->regmap,
 857                                   sx9500_default_regs[i].reg,
 858                                   sx9500_default_regs[i].def);
 859                if (ret < 0)
 860                        return ret;
 861        }
 862
 863        return sx9500_init_compensation(indio_dev);
 864}
 865
 866static const struct acpi_gpio_params reset_gpios = { 0, 0, false };
 867static const struct acpi_gpio_params interrupt_gpios = { 2, 0, false };
 868
 869static const struct acpi_gpio_mapping acpi_sx9500_gpios[] = {
 870        { "reset-gpios", &reset_gpios, 1 },
 871        /*
 872         * Some platforms have a bug in ACPI GPIO description making IRQ
 873         * GPIO to be output only. Ask the GPIO core to ignore this limit.
 874         */
 875        { "interrupt-gpios", &interrupt_gpios, 1, ACPI_GPIO_QUIRK_NO_IO_RESTRICTION },
 876        { },
 877};
 878
 879static void sx9500_gpio_probe(struct i2c_client *client,
 880                              struct sx9500_data *data)
 881{
 882        struct gpio_desc *gpiod_int;
 883        struct device *dev;
 884        int ret;
 885
 886        if (!client)
 887                return;
 888
 889        dev = &client->dev;
 890
 891        ret = devm_acpi_dev_add_driver_gpios(dev, acpi_sx9500_gpios);
 892        if (ret)
 893                dev_dbg(dev, "Unable to add GPIO mapping table\n");
 894
 895        if (client->irq <= 0) {
 896                gpiod_int = devm_gpiod_get(dev, "interrupt", GPIOD_IN);
 897                if (IS_ERR(gpiod_int))
 898                        dev_err(dev, "gpio get irq failed\n");
 899                else
 900                        client->irq = gpiod_to_irq(gpiod_int);
 901        }
 902
 903        data->gpiod_rst = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
 904        if (IS_ERR(data->gpiod_rst)) {
 905                dev_warn(dev, "gpio get reset pin failed\n");
 906                data->gpiod_rst = NULL;
 907        }
 908}
 909
 910static int sx9500_probe(struct i2c_client *client,
 911                        const struct i2c_device_id *id)
 912{
 913        int ret;
 914        struct iio_dev *indio_dev;
 915        struct sx9500_data *data;
 916
 917        indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 918        if (indio_dev == NULL)
 919                return -ENOMEM;
 920
 921        data = iio_priv(indio_dev);
 922        data->client = client;
 923        mutex_init(&data->mutex);
 924        init_completion(&data->completion);
 925        data->trigger_enabled = false;
 926
 927        data->regmap = devm_regmap_init_i2c(client, &sx9500_regmap_config);
 928        if (IS_ERR(data->regmap))
 929                return PTR_ERR(data->regmap);
 930
 931        indio_dev->dev.parent = &client->dev;
 932        indio_dev->name = SX9500_DRIVER_NAME;
 933        indio_dev->channels = sx9500_channels;
 934        indio_dev->num_channels = ARRAY_SIZE(sx9500_channels);
 935        indio_dev->info = &sx9500_info;
 936        indio_dev->modes = INDIO_DIRECT_MODE;
 937        i2c_set_clientdata(client, indio_dev);
 938
 939        sx9500_gpio_probe(client, data);
 940
 941        ret = sx9500_init_device(indio_dev);
 942        if (ret < 0)
 943                return ret;
 944
 945        if (client->irq <= 0)
 946                dev_warn(&client->dev, "no valid irq found\n");
 947        else {
 948                ret = devm_request_threaded_irq(&client->dev, client->irq,
 949                                sx9500_irq_handler, sx9500_irq_thread_handler,
 950                                IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
 951                                SX9500_IRQ_NAME, indio_dev);
 952                if (ret < 0)
 953                        return ret;
 954
 955                data->trig = devm_iio_trigger_alloc(&client->dev,
 956                                "%s-dev%d", indio_dev->name, indio_dev->id);
 957                if (!data->trig)
 958                        return -ENOMEM;
 959
 960                data->trig->dev.parent = &client->dev;
 961                data->trig->ops = &sx9500_trigger_ops;
 962                iio_trigger_set_drvdata(data->trig, indio_dev);
 963
 964                ret = iio_trigger_register(data->trig);
 965                if (ret)
 966                        return ret;
 967        }
 968
 969        ret = iio_triggered_buffer_setup(indio_dev, NULL,
 970                                         sx9500_trigger_handler,
 971                                         &sx9500_buffer_setup_ops);
 972        if (ret < 0)
 973                goto out_trigger_unregister;
 974
 975        ret = iio_device_register(indio_dev);
 976        if (ret < 0)
 977                goto out_buffer_cleanup;
 978
 979        return 0;
 980
 981out_buffer_cleanup:
 982        iio_triggered_buffer_cleanup(indio_dev);
 983out_trigger_unregister:
 984        if (client->irq > 0)
 985                iio_trigger_unregister(data->trig);
 986
 987        return ret;
 988}
 989
 990static int sx9500_remove(struct i2c_client *client)
 991{
 992        struct iio_dev *indio_dev = i2c_get_clientdata(client);
 993        struct sx9500_data *data = iio_priv(indio_dev);
 994
 995        iio_device_unregister(indio_dev);
 996        iio_triggered_buffer_cleanup(indio_dev);
 997        if (client->irq > 0)
 998                iio_trigger_unregister(data->trig);
 999        kfree(data->buffer);
1000
1001        return 0;
1002}
1003
1004#ifdef CONFIG_PM_SLEEP
1005static int sx9500_suspend(struct device *dev)
1006{
1007        struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1008        struct sx9500_data *data = iio_priv(indio_dev);
1009        int ret;
1010
1011        mutex_lock(&data->mutex);
1012        ret = regmap_read(data->regmap, SX9500_REG_PROX_CTRL0,
1013                          &data->suspend_ctrl0);
1014        if (ret < 0)
1015                goto out;
1016
1017        /*
1018         * Scan period doesn't matter because when all the sensors are
1019         * deactivated the device is in sleep mode.
1020         */
1021        ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0, 0);
1022
1023out:
1024        mutex_unlock(&data->mutex);
1025        return ret;
1026}
1027
1028static int sx9500_resume(struct device *dev)
1029{
1030        struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1031        struct sx9500_data *data = iio_priv(indio_dev);
1032        int ret;
1033
1034        mutex_lock(&data->mutex);
1035        ret = regmap_write(data->regmap, SX9500_REG_PROX_CTRL0,
1036                           data->suspend_ctrl0);
1037        mutex_unlock(&data->mutex);
1038
1039        return ret;
1040}
1041#endif /* CONFIG_PM_SLEEP */
1042
1043static const struct dev_pm_ops sx9500_pm_ops = {
1044        SET_SYSTEM_SLEEP_PM_OPS(sx9500_suspend, sx9500_resume)
1045};
1046
1047static const struct acpi_device_id sx9500_acpi_match[] = {
1048        {"SSX9500", 0},
1049        {"SASX9500", 0},
1050        { },
1051};
1052MODULE_DEVICE_TABLE(acpi, sx9500_acpi_match);
1053
1054static const struct of_device_id sx9500_of_match[] = {
1055        { .compatible = "semtech,sx9500", },
1056        { }
1057};
1058MODULE_DEVICE_TABLE(of, sx9500_of_match);
1059
1060static const struct i2c_device_id sx9500_id[] = {
1061        {"sx9500", 0},
1062        { },
1063};
1064MODULE_DEVICE_TABLE(i2c, sx9500_id);
1065
1066static struct i2c_driver sx9500_driver = {
1067        .driver = {
1068                .name   = SX9500_DRIVER_NAME,
1069                .acpi_match_table = ACPI_PTR(sx9500_acpi_match),
1070                .of_match_table = of_match_ptr(sx9500_of_match),
1071                .pm = &sx9500_pm_ops,
1072        },
1073        .probe          = sx9500_probe,
1074        .remove         = sx9500_remove,
1075        .id_table       = sx9500_id,
1076};
1077module_i2c_driver(sx9500_driver);
1078
1079MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
1080MODULE_DESCRIPTION("Driver for Semtech SX9500 proximity sensor");
1081MODULE_LICENSE("GPL v2");
1082