drivers/iio/proximity/sx9310.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright 2018 Google LLC.
   4  *
   5  * Driver for Semtech's SX9310/SX9311 capacitive proximity/button solution.
   6  * Based on SX9500 driver and Semtech driver using the input framework
   7  * <https://my.syncplicity.com/share/teouwsim8niiaud/
   8  *          linux-driver-SX9310_NoSmartHSensing>.
   9  * Reworked in April 2019 by Evan Green <evgreen@chromium.org>
  10  * and in January 2020 by Daniel Campello <campello@chromium.org>.
  11  */
  12
  13 #include <linux/acpi.h>
  14 #include <linux/bitfield.h>
  15 #include <linux/delay.h>
  16 #include <linux/i2c.h>
  17 #include <linux/irq.h>
  18 #include <linux/kernel.h>
  19 #include <linux/mod_devicetable.h>
  20 #include <linux/module.h>
  21 #include <linux/pm.h>
  22 #include <linux/regmap.h>
  23 #include <linux/regulator/consumer.h>
  24 #include <linux/slab.h>
  25
  26 #include <linux/iio/buffer.h>
  27 #include <linux/iio/events.h>
  28 #include <linux/iio/iio.h>
  29 #include <linux/iio/sysfs.h>
  30 #include <linux/iio/trigger.h>
  31 #include <linux/iio/triggered_buffer.h>
  32 #include <linux/iio/trigger_consumer.h>
  33
  34 /* Register definitions. */
  35 #define SX9310_REG_IRQ_SRC                              0x00
  36 #define SX9310_REG_STAT0                                0x01
  37 #define SX9310_REG_STAT1                                0x02
  38 #define SX9310_REG_STAT1_COMPSTAT_MASK                  GENMASK(3, 0)
  39 #define SX9310_REG_IRQ_MSK                              0x03
  40 #define   SX9310_CONVDONE_IRQ                           BIT(3)
  41 #define   SX9310_FAR_IRQ                                BIT(5)
  42 #define   SX9310_CLOSE_IRQ                              BIT(6)
  43 #define SX9310_REG_IRQ_FUNC                             0x04
  44
  45 #define SX9310_REG_PROX_CTRL0                           0x10
  46 #define   SX9310_REG_PROX_CTRL0_SENSOREN_MASK           GENMASK(3, 0)
  47 #define   SX9310_REG_PROX_CTRL0_SCANPERIOD_MASK         GENMASK(7, 4)
  48 #define   SX9310_REG_PROX_CTRL0_SCANPERIOD_15MS         0x01
  49 #define SX9310_REG_PROX_CTRL1                           0x11
  50 #define SX9310_REG_PROX_CTRL2                           0x12
  51 #define   SX9310_REG_PROX_CTRL2_COMBMODE_CS1_CS2        (0x02 << 6)
  52 #define   SX9310_REG_PROX_CTRL2_SHIELDEN_DYNAMIC        (0x01 << 2)
  53 #define SX9310_REG_PROX_CTRL3                           0x13
  54 #define   SX9310_REG_PROX_CTRL3_GAIN0_X8                (0x03 << 2)
  55 #define   SX9310_REG_PROX_CTRL3_GAIN12_X4               0x02
  56 #define SX9310_REG_PROX_CTRL4                           0x14
  57 #define   SX9310_REG_PROX_CTRL4_RESOLUTION_FINEST       0x07
  58 #define SX9310_REG_PROX_CTRL5                           0x15
  59 #define   SX9310_REG_PROX_CTRL5_RANGE_SMALL             (0x03 << 6)
  60 #define   SX9310_REG_PROX_CTRL5_STARTUPSENS_CS1         (0x01 << 2)
  61 #define   SX9310_REG_PROX_CTRL5_RAWFILT_1P25            0x02
  62 #define SX9310_REG_PROX_CTRL6                           0x16
  63 #define   SX9310_REG_PROX_CTRL6_AVGTHRESH_DEFAULT       0x20
  64 #define SX9310_REG_PROX_CTRL7                           0x17
  65 #define   SX9310_REG_PROX_CTRL7_AVGNEGFILT_2            (0x01 << 3)
  66 #define   SX9310_REG_PROX_CTRL7_AVGPOSFILT_512          0x05
  67 #define SX9310_REG_PROX_CTRL8                           0x18
  68 #define SX9310_REG_PROX_CTRL9                           0x19
  69 #define   SX9310_REG_PROX_CTRL8_9_PTHRESH_28            (0x08 << 3)
  70 #define   SX9310_REG_PROX_CTRL8_9_PTHRESH_96            (0x11 << 3)
  71 #define   SX9310_REG_PROX_CTRL8_9_BODYTHRESH_900        0x03
  72 #define   SX9310_REG_PROX_CTRL8_9_BODYTHRESH_1500       0x05
  73 #define SX9310_REG_PROX_CTRL10                          0x1a
  74 #define   SX9310_REG_PROX_CTRL10_HYST_6PCT              (0x01 << 4)
  75 #define   SX9310_REG_PROX_CTRL10_FAR_DEBOUNCE_2         0x01
  76 #define SX9310_REG_PROX_CTRL11                          0x1b
  77 #define SX9310_REG_PROX_CTRL12                          0x1c
  78 #define SX9310_REG_PROX_CTRL13                          0x1d
  79 #define SX9310_REG_PROX_CTRL14                          0x1e
  80 #define SX9310_REG_PROX_CTRL15                          0x1f
  81 #define SX9310_REG_PROX_CTRL16                          0x20
  82 #define SX9310_REG_PROX_CTRL17                          0x21
  83 #define SX9310_REG_PROX_CTRL18                          0x22
  84 #define SX9310_REG_PROX_CTRL19                          0x23
  85 #define SX9310_REG_SAR_CTRL0                            0x2a
  86 #define   SX9310_REG_SAR_CTRL0_SARDEB_4_SAMPLES         (0x02 << 5)
  87 #define   SX9310_REG_SAR_CTRL0_SARHYST_8                (0x02 << 3)
  88 #define SX9310_REG_SAR_CTRL1                            0x2b
  89 /* Each increment of the slope register is 0.0078125. */
  90 #define   SX9310_REG_SAR_CTRL1_SLOPE(_hnslope)          (_hnslope / 78125)
  91 #define SX9310_REG_SAR_CTRL2                            0x2c
  92 #define   SX9310_REG_SAR_CTRL2_SAROFFSET_DEFAULT        0x3c
  93
  94 #define SX9310_REG_SENSOR_SEL                           0x30
  95 #define SX9310_REG_USE_MSB                              0x31
  96 #define SX9310_REG_USE_LSB                              0x32
  97 #define SX9310_REG_AVG_MSB                              0x33
  98 #define SX9310_REG_AVG_LSB                              0x34
  99 #define SX9310_REG_DIFF_MSB                             0x35
 100 #define SX9310_REG_DIFF_LSB                             0x36
 101 #define SX9310_REG_OFFSET_MSB                           0x37
 102 #define SX9310_REG_OFFSET_LSB                           0x38
 103 #define SX9310_REG_SAR_MSB                              0x39
 104 #define SX9310_REG_SAR_LSB                              0x3a
 105 #define SX9310_REG_I2C_ADDR                             0x40
 106 #define SX9310_REG_PAUSE                                0x41
 107 #define SX9310_REG_WHOAMI                               0x42
 108 #define   SX9310_WHOAMI_VALUE                           0x01
 109 #define   SX9311_WHOAMI_VALUE                           0x02
 110 #define SX9310_REG_RESET                                0x7f
 111 #define   SX9310_SOFT_RESET                             0xde
 112
 113
 114 /* 4 hardware channels, as defined in STAT0: COMB, CS2, CS1 and CS0. */
 115 #define SX9310_NUM_CHANNELS                             4
 116 static_assert(SX9310_NUM_CHANNELS < BITS_PER_LONG);
 117
 118 struct sx9310_data {
 119         /* Serialize access to registers and channel configuration */
 120         struct mutex mutex;
 121         struct i2c_client *client;
 122         struct iio_trigger *trig;
 123         struct regmap *regmap;
 124         struct regulator_bulk_data supplies[2];
 125         /*
 126          * Last reading of the proximity status for each channel.
 127          * We only send an event to user space when this changes.
 128          */
 129         unsigned long chan_prox_stat;
 130         bool trigger_enabled;
 131         /* Ensure correct alignment of timestamp when present. */
 132         struct {
 133                 __be16 channels[SX9310_NUM_CHANNELS];
 134                 s64 ts __aligned(8);
 135         } buffer;
 136         /* Remember enabled channels and sample rate during suspend. */
 137         unsigned int suspend_ctrl0;
 138         struct completion completion;
 139         unsigned long chan_read;
 140         unsigned long chan_event;
 141         unsigned int whoami;
 142 };
 143
 144 static const struct iio_event_spec sx9310_events[] = {
 145         {
 146                 .type = IIO_EV_TYPE_THRESH,
 147                 .dir = IIO_EV_DIR_EITHER,
 148                 .mask_separate = BIT(IIO_EV_INFO_ENABLE),
 149         },
 150 };
 151
 152 #define SX9310_NAMED_CHANNEL(idx, name)                                  \
 153         {                                                                \
 154                 .type = IIO_PROXIMITY,                                   \
 155                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),            \
 156                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
 157                 .indexed = 1,                                            \
 158                 .channel = idx,                                          \
 159                 .extend_name = name,                                     \
 160                 .address = SX9310_REG_DIFF_MSB,                          \
 161                 .event_spec = sx9310_events,                             \
 162                 .num_event_specs = ARRAY_SIZE(sx9310_events),            \
 163                 .scan_index = idx,                                       \
 164                 .scan_type = {                                           \
 165                         .sign = 's',                                     \
 166                         .realbits = 12,                                  \
 167                         .storagebits = 16,                               \
 168                         .endianness = IIO_BE,                            \
 169                 },                                                       \
 170         }
 171 #define SX9310_CHANNEL(idx) SX9310_NAMED_CHANNEL(idx, NULL)
 172
 173 static const struct iio_chan_spec sx9310_channels[] = {
 174         SX9310_CHANNEL(0),                      /* CS0 */
 175         SX9310_CHANNEL(1),                      /* CS1 */
 176         SX9310_CHANNEL(2),                      /* CS2 */
 177         SX9310_NAMED_CHANNEL(3, "comb"),        /* COMB */
 178
 179         IIO_CHAN_SOFT_TIMESTAMP(4),
 180 };
 181
 182 /*
 183  * Each entry contains the integer part (val) and the fractional part, in micro
 184  * seconds. It conforms to the IIO output IIO_VAL_INT_PLUS_MICRO.
 185  */
 186 static const struct {
 187         int val;
 188         int val2;
 189 } sx9310_samp_freq_table[] = {
 190         { 500, 0 }, /* 0000: Min (no idle time) */
 191         { 66, 666666 }, /* 0001: 15 ms */
 192         { 33, 333333 }, /* 0010: 30 ms (Typ.) */
 193         { 22, 222222 }, /* 0011: 45 ms */
 194         { 16, 666666 }, /* 0100: 60 ms */
 195         { 11, 111111 }, /* 0101: 90 ms */
 196         { 8, 333333 }, /* 0110: 120 ms */
 197         { 5, 0 }, /* 0111: 200 ms */
 198         { 2, 500000 }, /* 1000: 400 ms */
 199         { 1, 666666 }, /* 1001: 600 ms */
 200         { 1, 250000 }, /* 1010: 800 ms */
 201         { 1, 0 }, /* 1011: 1 s */
 202         { 0, 500000 }, /* 1100: 2 s */
 203         { 0, 333333 }, /* 1101: 3 s */
 204         { 0, 250000 }, /* 1110: 4 s */
 205         { 0, 200000 }, /* 1111: 5 s */
 206 };
 207 static const unsigned int sx9310_scan_period_table[] = {
 208         2,   15,  30,  45,   60,   90,   120,  200,
 209         400, 600, 800, 1000, 2000, 3000, 4000, 5000,
 210 };
 211
 212 static ssize_t sx9310_show_samp_freq_avail(struct device *dev,
 213                                            struct device_attribute *attr,
 214                                            char *buf)
 215 {
 216         size_t len = 0;
 217         int i;
 218
 219         for (i = 0; i < ARRAY_SIZE(sx9310_samp_freq_table); i++)
 220                 len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%d ",
 221                                  sx9310_samp_freq_table[i].val,
 222                                  sx9310_samp_freq_table[i].val2);
 223         buf[len - 1] = '\n';
 224         return len;
 225 }
 226 static IIO_DEV_ATTR_SAMP_FREQ_AVAIL(sx9310_show_samp_freq_avail);
 227
 228 static const struct regmap_range sx9310_writable_reg_ranges[] = {
 229         regmap_reg_range(SX9310_REG_IRQ_MSK, SX9310_REG_IRQ_FUNC),
 230         regmap_reg_range(SX9310_REG_PROX_CTRL0, SX9310_REG_PROX_CTRL19),
 231         regmap_reg_range(SX9310_REG_SAR_CTRL0, SX9310_REG_SAR_CTRL2),
 232         regmap_reg_range(SX9310_REG_SENSOR_SEL, SX9310_REG_SENSOR_SEL),
 233         regmap_reg_range(SX9310_REG_OFFSET_MSB, SX9310_REG_OFFSET_LSB),
 234         regmap_reg_range(SX9310_REG_PAUSE, SX9310_REG_PAUSE),
 235         regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
 236 };
 237
 238 static const struct regmap_access_table sx9310_writeable_regs = {
 239         .yes_ranges = sx9310_writable_reg_ranges,
 240         .n_yes_ranges = ARRAY_SIZE(sx9310_writable_reg_ranges),
 241 };
 242
 243 static const struct regmap_range sx9310_readable_reg_ranges[] = {
 244         regmap_reg_range(SX9310_REG_IRQ_SRC, SX9310_REG_IRQ_FUNC),
 245         regmap_reg_range(SX9310_REG_PROX_CTRL0, SX9310_REG_PROX_CTRL19),
 246         regmap_reg_range(SX9310_REG_SAR_CTRL0, SX9310_REG_SAR_CTRL2),
 247         regmap_reg_range(SX9310_REG_SENSOR_SEL, SX9310_REG_SAR_LSB),
 248         regmap_reg_range(SX9310_REG_I2C_ADDR, SX9310_REG_WHOAMI),
 249         regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
 250 };
 251
 252 static const struct regmap_access_table sx9310_readable_regs = {
 253         .yes_ranges = sx9310_readable_reg_ranges,
 254         .n_yes_ranges = ARRAY_SIZE(sx9310_readable_reg_ranges),
 255 };
 256
 257 static const struct regmap_range sx9310_volatile_reg_ranges[] = {
 258         regmap_reg_range(SX9310_REG_IRQ_SRC, SX9310_REG_STAT1),
 259         regmap_reg_range(SX9310_REG_USE_MSB, SX9310_REG_DIFF_LSB),
 260         regmap_reg_range(SX9310_REG_SAR_MSB, SX9310_REG_SAR_LSB),
 261         regmap_reg_range(SX9310_REG_RESET, SX9310_REG_RESET),
 262 };
 263
 264 static const struct regmap_access_table sx9310_volatile_regs = {
 265         .yes_ranges = sx9310_volatile_reg_ranges,
 266         .n_yes_ranges = ARRAY_SIZE(sx9310_volatile_reg_ranges),
 267 };
 268
 269 static const struct regmap_config sx9310_regmap_config = {
 270         .reg_bits = 8,
 271         .val_bits = 8,
 272
 273         .max_register = SX9310_REG_RESET,
 274         .cache_type = REGCACHE_RBTREE,
 275
 276         .wr_table = &sx9310_writeable_regs,
 277         .rd_table = &sx9310_readable_regs,
 278         .volatile_table = &sx9310_volatile_regs,
 279 };
 280
 281 static int sx9310_update_chan_en(struct sx9310_data *data,
 282                                  unsigned long chan_read,
 283                                  unsigned long chan_event)
 284 {
 285         int ret;
 286         unsigned long channels = chan_read | chan_event;
 287
 288         if ((data->chan_read | data->chan_event) != channels) {
 289                 ret = regmap_update_bits(data->regmap, SX9310_REG_PROX_CTRL0,
 290                                          SX9310_REG_PROX_CTRL0_SENSOREN_MASK,
 291                                          channels);
 292                 if (ret)
 293                         return ret;
 294         }
 295         data->chan_read = chan_read;
 296         data->chan_event = chan_event;
 297         return 0;
 298 }
 299
 300 static int sx9310_get_read_channel(struct sx9310_data *data, int channel)
 301 {
 302         return sx9310_update_chan_en(data, data->chan_read | BIT(channel),
 303                                      data->chan_event);
 304 }
 305
 306 static int sx9310_put_read_channel(struct sx9310_data *data, int channel)
 307 {
 308         return sx9310_update_chan_en(data, data->chan_read & ~BIT(channel),
 309                                      data->chan_event);
 310 }
 311
 312 static int sx9310_get_event_channel(struct sx9310_data *data, int channel)
 313 {
 314         return sx9310_update_chan_en(data, data->chan_read,
 315                                      data->chan_event | BIT(channel));
 316 }
 317
 318 static int sx9310_put_event_channel(struct sx9310_data *data, int channel)
 319 {
 320         return sx9310_update_chan_en(data, data->chan_read,
 321                                      data->chan_event & ~BIT(channel));
 322 }
 323
 324 static int sx9310_enable_irq(struct sx9310_data *data, unsigned int irq)
 325 {
 326         if (!data->client->irq)
 327                 return 0;
 328         return regmap_update_bits(data->regmap, SX9310_REG_IRQ_MSK, irq, irq);
 329 }
 330
 331 static int sx9310_disable_irq(struct sx9310_data *data, unsigned int irq)
 332 {
 333         if (!data->client->irq)
 334                 return 0;
 335         return regmap_update_bits(data->regmap, SX9310_REG_IRQ_MSK, irq, 0);
 336 }
 337
 338 static int sx9310_read_prox_data(struct sx9310_data *data,
 339                                  const struct iio_chan_spec *chan, __be16 *val)
 340 {
 341         int ret;
 342
 343         ret = regmap_write(data->regmap, SX9310_REG_SENSOR_SEL, chan->channel);
 344         if (ret)
 345                 return ret;
 346
 347         return regmap_bulk_read(data->regmap, chan->address, val, sizeof(*val));
 348 }
 349
 350 /*
 351  * If we have no interrupt support, we have to wait for a scan period
 352  * after enabling a channel to get a result.
 353  */
 354 static int sx9310_wait_for_sample(struct sx9310_data *data)
 355 {
 356         int ret;
 357         unsigned int val;
 358
 359         ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &val);
 360         if (ret)
 361                 return ret;
 362
 363         val = FIELD_GET(SX9310_REG_PROX_CTRL0_SCANPERIOD_MASK, val);
 364
 365         msleep(sx9310_scan_period_table[val]);
 366
 367         return 0;
 368 }
 369
 370 static int sx9310_read_proximity(struct sx9310_data *data,
 371                                  const struct iio_chan_spec *chan, int *val)
 372 {
 373         int ret;
 374         __be16 rawval;
 375
 376         mutex_lock(&data->mutex);
 377
 378         ret = sx9310_get_read_channel(data, chan->channel);
 379         if (ret)
 380                 goto out;
 381
 382         ret = sx9310_enable_irq(data, SX9310_CONVDONE_IRQ);
 383         if (ret)
 384                 goto out_put_channel;
 385
 386         mutex_unlock(&data->mutex);
 387
 388         if (data->client->irq) {
 389                 ret = wait_for_completion_interruptible(&data->completion);
 390                 reinit_completion(&data->completion);
 391         } else {
 392                 ret = sx9310_wait_for_sample(data);
 393         }
 394
 395         mutex_lock(&data->mutex);
 396
 397         if (ret)
 398                 goto out_disable_irq;
 399
 400         ret = sx9310_read_prox_data(data, chan, &rawval);
 401         if (ret)
 402                 goto out_disable_irq;
 403
 404         *val = sign_extend32(be16_to_cpu(rawval),
 405                              chan->address == SX9310_REG_DIFF_MSB ? 11 : 15);
 406
 407         ret = sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
 408         if (ret)
 409                 goto out_put_channel;
 410
 411         ret = sx9310_put_read_channel(data, chan->channel);
 412         if (ret)
 413                 goto out;
 414
 415         mutex_unlock(&data->mutex);
 416
 417         return IIO_VAL_INT;
 418
 419 out_disable_irq:
 420         sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
 421 out_put_channel:
 422         sx9310_put_read_channel(data, chan->channel);
 423 out:
 424         mutex_unlock(&data->mutex);
 425
 426         return ret;
 427 }
 428
 429 static int sx9310_read_samp_freq(struct sx9310_data *data, int *val, int *val2)
 430 {
 431         unsigned int regval;
 432         int ret;
 433
 434         ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &regval);
 435         if (ret)
 436                 return ret;
 437
 438         regval = FIELD_GET(SX9310_REG_PROX_CTRL0_SCANPERIOD_MASK, regval);
 439         *val = sx9310_samp_freq_table[regval].val;
 440         *val2 = sx9310_samp_freq_table[regval].val2;
 441
 442         return IIO_VAL_INT_PLUS_MICRO;
 443 }
 444
 445 static int sx9310_read_raw(struct iio_dev *indio_dev,
 446                            const struct iio_chan_spec *chan, int *val,
 447                            int *val2, long mask)
 448 {
 449         struct sx9310_data *data = iio_priv(indio_dev);
 450         int ret;
 451
 452         if (chan->type != IIO_PROXIMITY)
 453                 return -EINVAL;
 454
 455         switch (mask) {
 456         case IIO_CHAN_INFO_RAW:
 457                 ret = iio_device_claim_direct_mode(indio_dev);
 458                 if (ret)
 459                         return ret;
 460
 461                 ret = sx9310_read_proximity(data, chan, val);
 462                 iio_device_release_direct_mode(indio_dev);
 463                 return ret;
 464         case IIO_CHAN_INFO_SAMP_FREQ:
 465                 return sx9310_read_samp_freq(data, val, val2);
 466         default:
 467                 return -EINVAL;
 468         }
 469 }
 470
 471 static int sx9310_set_samp_freq(struct sx9310_data *data, int val, int val2)
 472 {
 473         int i, ret;
 474
 475         for (i = 0; i < ARRAY_SIZE(sx9310_samp_freq_table); i++)
 476                 if (val == sx9310_samp_freq_table[i].val &&
 477                     val2 == sx9310_samp_freq_table[i].val2)
 478                         break;
 479
 480         if (i == ARRAY_SIZE(sx9310_samp_freq_table))
 481                 return -EINVAL;
 482
 483         mutex_lock(&data->mutex);
 484
 485         ret = regmap_update_bits(
 486                 data->regmap, SX9310_REG_PROX_CTRL0,
 487                 SX9310_REG_PROX_CTRL0_SCANPERIOD_MASK,
 488                 FIELD_PREP(SX9310_REG_PROX_CTRL0_SCANPERIOD_MASK, i));
 489
 490         mutex_unlock(&data->mutex);
 491
 492         return ret;
 493 }
 494
 495 static int sx9310_write_raw(struct iio_dev *indio_dev,
 496                             const struct iio_chan_spec *chan, int val, int val2,
 497                             long mask)
 498 {
 499         struct sx9310_data *data = iio_priv(indio_dev);
 500
 501         if (chan->type != IIO_PROXIMITY)
 502                 return -EINVAL;
 503
 504         if (mask != IIO_CHAN_INFO_SAMP_FREQ)
 505                 return -EINVAL;
 506
 507         return sx9310_set_samp_freq(data, val, val2);
 508 }
 509
 510 static irqreturn_t sx9310_irq_handler(int irq, void *private)
 511 {
 512         struct iio_dev *indio_dev = private;
 513         struct sx9310_data *data = iio_priv(indio_dev);
 514
 515         if (data->trigger_enabled)
 516                 iio_trigger_poll(data->trig);
 517
 518         /*
 519          * Even if no event is enabled, we need to wake the thread to clear the
 520          * interrupt state by reading SX9310_REG_IRQ_SRC.
 521          * It is not possible to do that here because regmap_read takes a mutex.
 522          */
 523         return IRQ_WAKE_THREAD;
 524 }
 525
 526 static void sx9310_push_events(struct iio_dev *indio_dev)
 527 {
 528         int ret;
 529         unsigned int val, chan;
 530         struct sx9310_data *data = iio_priv(indio_dev);
 531         s64 timestamp = iio_get_time_ns(indio_dev);
 532         unsigned long prox_changed;
 533
 534         /* Read proximity state on all channels */
 535         ret = regmap_read(data->regmap, SX9310_REG_STAT0, &val);
 536         if (ret) {
 537                 dev_err(&data->client->dev, "i2c transfer error in irq\n");
 538                 return;
 539         }
 540
 541         /*
 542          * Only iterate over channels with changes on proximity status that have
 543          * events enabled.
 544          */
 545         prox_changed = (data->chan_prox_stat ^ val) & data->chan_event;
 546
 547         for_each_set_bit(chan, &prox_changed, SX9310_NUM_CHANNELS) {
 548                 int dir;
 549                 u64 ev;
 550
 551                 dir = (val & BIT(chan)) ? IIO_EV_DIR_FALLING : IIO_EV_DIR_RISING;
 552                 ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, chan,
 553                                           IIO_EV_TYPE_THRESH, dir);
 554
 555                 iio_push_event(indio_dev, ev, timestamp);
 556         }
 557         data->chan_prox_stat = val;
 558 }
 559
 560 static irqreturn_t sx9310_irq_thread_handler(int irq, void *private)
 561 {
 562         struct iio_dev *indio_dev = private;
 563         struct sx9310_data *data = iio_priv(indio_dev);
 564         int ret;
 565         unsigned int val;
 566
 567         mutex_lock(&data->mutex);
 568
 569         ret = regmap_read(data->regmap, SX9310_REG_IRQ_SRC, &val);
 570         if (ret) {
 571                 dev_err(&data->client->dev, "i2c transfer error in irq\n");
 572                 goto out;
 573         }
 574
 575         if (val & (SX9310_FAR_IRQ | SX9310_CLOSE_IRQ))
 576                 sx9310_push_events(indio_dev);
 577
 578         if (val & SX9310_CONVDONE_IRQ)
 579                 complete(&data->completion);
 580
 581 out:
 582         mutex_unlock(&data->mutex);
 583
 584         return IRQ_HANDLED;
 585 }
 586
 587 static int sx9310_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 sx9310_data *data = iio_priv(indio_dev);
 593
 594         return !!(data->chan_event & BIT(chan->channel));
 595 }
 596
 597 static int sx9310_write_event_config(struct iio_dev *indio_dev,
 598                                      const struct iio_chan_spec *chan,
 599                                      enum iio_event_type type,
 600                                      enum iio_event_direction dir, int state)
 601 {
 602         struct sx9310_data *data = iio_priv(indio_dev);
 603         unsigned int eventirq = SX9310_FAR_IRQ | SX9310_CLOSE_IRQ;
 604         int ret;
 605
 606         /* If the state hasn't changed, there's nothing to do. */
 607         if (!!(data->chan_event & BIT(chan->channel)) == state)
 608                 return 0;
 609
 610         mutex_lock(&data->mutex);
 611         if (state) {
 612                 ret = sx9310_get_event_channel(data, chan->channel);
 613                 if (ret)
 614                         goto out_unlock;
 615                 if (!(data->chan_event & ~BIT(chan->channel))) {
 616                         ret = sx9310_enable_irq(data, eventirq);
 617                         if (ret)
 618                                 sx9310_put_event_channel(data, chan->channel);
 619                 }
 620         } else {
 621                 ret = sx9310_put_event_channel(data, chan->channel);
 622                 if (ret)
 623                         goto out_unlock;
 624                 if (!data->chan_event) {
 625                         ret = sx9310_disable_irq(data, eventirq);
 626                         if (ret)
 627                                 sx9310_get_event_channel(data, chan->channel);
 628                 }
 629         }
 630
 631 out_unlock:
 632         mutex_unlock(&data->mutex);
 633         return ret;
 634 }
 635
 636 static struct attribute *sx9310_attributes[] = {
 637         &iio_dev_attr_sampling_frequency_available.dev_attr.attr,
 638         NULL
 639 };
 640
 641 static const struct attribute_group sx9310_attribute_group = {
 642         .attrs = sx9310_attributes,
 643 };
 644
 645 static const struct iio_info sx9310_info = {
 646         .attrs = &sx9310_attribute_group,
 647         .read_raw = sx9310_read_raw,
 648         .write_raw = sx9310_write_raw,
 649         .read_event_config = sx9310_read_event_config,
 650         .write_event_config = sx9310_write_event_config,
 651 };
 652
 653 static int sx9310_set_trigger_state(struct iio_trigger *trig, bool state)
 654 {
 655         struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
 656         struct sx9310_data *data = iio_priv(indio_dev);
 657         int ret = 0;
 658
 659         mutex_lock(&data->mutex);
 660
 661         if (state)
 662                 ret = sx9310_enable_irq(data, SX9310_CONVDONE_IRQ);
 663         else if (!data->chan_read)
 664                 ret = sx9310_disable_irq(data, SX9310_CONVDONE_IRQ);
 665         if (ret)
 666                 goto out;
 667
 668         data->trigger_enabled = state;
 669
 670 out:
 671         mutex_unlock(&data->mutex);
 672
 673         return ret;
 674 }
 675
 676 static const struct iio_trigger_ops sx9310_trigger_ops = {
 677         .set_trigger_state = sx9310_set_trigger_state,
 678 };
 679
 680 static irqreturn_t sx9310_trigger_handler(int irq, void *private)
 681 {
 682         struct iio_poll_func *pf = private;
 683         struct iio_dev *indio_dev = pf->indio_dev;
 684         struct sx9310_data *data = iio_priv(indio_dev);
 685         __be16 val;
 686         int bit, ret, i = 0;
 687
 688         mutex_lock(&data->mutex);
 689
 690         for_each_set_bit(bit, indio_dev->active_scan_mask,
 691                          indio_dev->masklength) {
 692                 ret = sx9310_read_prox_data(data, &indio_dev->channels[bit],
 693                                             &val);
 694                 if (ret)
 695                         goto out;
 696
 697                 data->buffer.channels[i++] = val;
 698         }
 699
 700         iio_push_to_buffers_with_timestamp(indio_dev, &data->buffer,
 701                                            pf->timestamp);
 702
 703 out:
 704         mutex_unlock(&data->mutex);
 705
 706         iio_trigger_notify_done(indio_dev->trig);
 707
 708         return IRQ_HANDLED;
 709 }
 710
 711 static int sx9310_buffer_preenable(struct iio_dev *indio_dev)
 712 {
 713         struct sx9310_data *data = iio_priv(indio_dev);
 714         unsigned long channels = 0;
 715         int bit, ret;
 716
 717         mutex_lock(&data->mutex);
 718         for_each_set_bit(bit, indio_dev->active_scan_mask,
 719                          indio_dev->masklength)
 720                 __set_bit(indio_dev->channels[bit].channel, &channels);
 721
 722         ret = sx9310_update_chan_en(data, channels, data->chan_event);
 723         mutex_unlock(&data->mutex);
 724         return ret;
 725 }
 726
 727 static int sx9310_buffer_postdisable(struct iio_dev *indio_dev)
 728 {
 729         struct sx9310_data *data = iio_priv(indio_dev);
 730         int ret;
 731
 732         mutex_lock(&data->mutex);
 733         ret = sx9310_update_chan_en(data, 0, data->chan_event);
 734         mutex_unlock(&data->mutex);
 735         return ret;
 736 }
 737
 738 static const struct iio_buffer_setup_ops sx9310_buffer_setup_ops = {
 739         .preenable = sx9310_buffer_preenable,
 740         .postdisable = sx9310_buffer_postdisable,
 741 };
 742
 743 struct sx9310_reg_default {
 744         u8 reg;
 745         u8 def;
 746 };
 747
 748 static const struct sx9310_reg_default sx9310_default_regs[] = {
 749         { SX9310_REG_IRQ_MSK, 0x00 },
 750         { SX9310_REG_IRQ_FUNC, 0x00 },
 751         /*
 752          * The lower 4 bits should not be set as it enable sensors measurements.
 753          * Turning the detection on before the configuration values are set to
 754          * good values can cause the device to return erroneous readings.
 755          */
 756         { SX9310_REG_PROX_CTRL0, SX9310_REG_PROX_CTRL0_SCANPERIOD_15MS },
 757         { SX9310_REG_PROX_CTRL1, 0x00 },
 758         { SX9310_REG_PROX_CTRL2, SX9310_REG_PROX_CTRL2_COMBMODE_CS1_CS2 |
 759                                  SX9310_REG_PROX_CTRL2_SHIELDEN_DYNAMIC },
 760         { SX9310_REG_PROX_CTRL3, SX9310_REG_PROX_CTRL3_GAIN0_X8 |
 761                                  SX9310_REG_PROX_CTRL3_GAIN12_X4 },
 762         { SX9310_REG_PROX_CTRL4, SX9310_REG_PROX_CTRL4_RESOLUTION_FINEST },
 763         { SX9310_REG_PROX_CTRL5, SX9310_REG_PROX_CTRL5_RANGE_SMALL |
 764                                  SX9310_REG_PROX_CTRL5_STARTUPSENS_CS1 |
 765                                  SX9310_REG_PROX_CTRL5_RAWFILT_1P25 },
 766         { SX9310_REG_PROX_CTRL6, SX9310_REG_PROX_CTRL6_AVGTHRESH_DEFAULT },
 767         { SX9310_REG_PROX_CTRL7, SX9310_REG_PROX_CTRL7_AVGNEGFILT_2 |
 768                                  SX9310_REG_PROX_CTRL7_AVGPOSFILT_512 },
 769         { SX9310_REG_PROX_CTRL8, SX9310_REG_PROX_CTRL8_9_PTHRESH_96 |
 770                                  SX9310_REG_PROX_CTRL8_9_BODYTHRESH_1500 },
 771         { SX9310_REG_PROX_CTRL9, SX9310_REG_PROX_CTRL8_9_PTHRESH_28 |
 772                                  SX9310_REG_PROX_CTRL8_9_BODYTHRESH_900 },
 773         { SX9310_REG_PROX_CTRL10, SX9310_REG_PROX_CTRL10_HYST_6PCT |
 774                                   SX9310_REG_PROX_CTRL10_FAR_DEBOUNCE_2 },
 775         { SX9310_REG_PROX_CTRL11, 0x00 },
 776         { SX9310_REG_PROX_CTRL12, 0x00 },
 777         { SX9310_REG_PROX_CTRL13, 0x00 },
 778         { SX9310_REG_PROX_CTRL14, 0x00 },
 779         { SX9310_REG_PROX_CTRL15, 0x00 },
 780         { SX9310_REG_PROX_CTRL16, 0x00 },
 781         { SX9310_REG_PROX_CTRL17, 0x00 },
 782         { SX9310_REG_PROX_CTRL18, 0x00 },
 783         { SX9310_REG_PROX_CTRL19, 0x00 },
 784         { SX9310_REG_SAR_CTRL0, SX9310_REG_SAR_CTRL0_SARDEB_4_SAMPLES |
 785                                 SX9310_REG_SAR_CTRL0_SARHYST_8 },
 786         { SX9310_REG_SAR_CTRL1, SX9310_REG_SAR_CTRL1_SLOPE(10781250) },
 787         { SX9310_REG_SAR_CTRL2, SX9310_REG_SAR_CTRL2_SAROFFSET_DEFAULT },
 788 };
 789
 790 /* Activate all channels and perform an initial compensation. */
 791 static int sx9310_init_compensation(struct iio_dev *indio_dev)
 792 {
 793         struct sx9310_data *data = iio_priv(indio_dev);
 794         int ret;
 795         unsigned int val;
 796         unsigned int ctrl0;
 797
 798         ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0, &ctrl0);
 799         if (ret)
 800                 return ret;
 801
 802         /* run the compensation phase on all channels */
 803         ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0,
 804                            ctrl0 | SX9310_REG_PROX_CTRL0_SENSOREN_MASK);
 805         if (ret)
 806                 return ret;
 807
 808         ret = regmap_read_poll_timeout(data->regmap, SX9310_REG_STAT1, val,
 809                                        !(val & SX9310_REG_STAT1_COMPSTAT_MASK),
 810                                        20000, 2000000);
 811         if (ret) {
 812                 if (ret == -ETIMEDOUT)
 813                         dev_err(&data->client->dev,
 814                                 "initial compensation timed out: 0x%02x\n",
 815                                 val);
 816                 return ret;
 817         }
 818
 819         regmap_write(data->regmap, SX9310_REG_PROX_CTRL0, ctrl0);
 820         return ret;
 821 }
 822
 823 static int sx9310_init_device(struct iio_dev *indio_dev)
 824 {
 825         struct sx9310_data *data = iio_priv(indio_dev);
 826         const struct sx9310_reg_default *initval;
 827         int ret;
 828         unsigned int i, val;
 829
 830         ret = regmap_write(data->regmap, SX9310_REG_RESET, SX9310_SOFT_RESET);
 831         if (ret)
 832                 return ret;
 833
 834         usleep_range(1000, 2000); /* power-up time is ~1ms. */
 835
 836         /* Clear reset interrupt state by reading SX9310_REG_IRQ_SRC. */
 837         ret = regmap_read(data->regmap, SX9310_REG_IRQ_SRC, &val);
 838         if (ret)
 839                 return ret;
 840
 841         /* Program some sane defaults. */
 842         for (i = 0; i < ARRAY_SIZE(sx9310_default_regs); i++) {
 843                 initval = &sx9310_default_regs[i];
 844                 ret = regmap_write(data->regmap, initval->reg, initval->def);
 845                 if (ret)
 846                         return ret;
 847         }
 848
 849         return sx9310_init_compensation(indio_dev);
 850 }
 851
 852 static int sx9310_set_indio_dev_name(struct device *dev,
 853                                      struct iio_dev *indio_dev,
 854                                      unsigned int whoami)
 855 {
 856         unsigned int long ddata;
 857
 858         ddata = (uintptr_t)device_get_match_data(dev);
 859         if (ddata != whoami) {
 860                 dev_err(dev, "WHOAMI does not match device data: %u\n", whoami);
 861                 return -ENODEV;
 862         }
 863
 864         switch (whoami) {
 865         case SX9310_WHOAMI_VALUE:
 866                 indio_dev->name = "sx9310";
 867                 break;
 868         case SX9311_WHOAMI_VALUE:
 869                 indio_dev->name = "sx9311";
 870                 break;
 871         default:
 872                 dev_err(dev, "unexpected WHOAMI response: %u\n", whoami);
 873                 return -ENODEV;
 874         }
 875
 876         return 0;
 877 }
 878
 879 static void sx9310_regulator_disable(void *_data)
 880 {
 881         struct sx9310_data *data = _data;
 882
 883         regulator_bulk_disable(ARRAY_SIZE(data->supplies), data->supplies);
 884 }
 885
 886 static int sx9310_probe(struct i2c_client *client)
 887 {
 888         int ret;
 889         struct device *dev = &client->dev;
 890         struct iio_dev *indio_dev;
 891         struct sx9310_data *data;
 892
 893         indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
 894         if (!indio_dev)
 895                 return -ENOMEM;
 896
 897         data = iio_priv(indio_dev);
 898         data->client = client;
 899         data->supplies[0].supply = "vdd";
 900         data->supplies[1].supply = "svdd";
 901         mutex_init(&data->mutex);
 902         init_completion(&data->completion);
 903
 904         data->regmap = devm_regmap_init_i2c(client, &sx9310_regmap_config);
 905         if (IS_ERR(data->regmap))
 906                 return PTR_ERR(data->regmap);
 907
 908         ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->supplies),
 909                                       data->supplies);
 910         if (ret)
 911                 return ret;
 912
 913         ret = regulator_bulk_enable(ARRAY_SIZE(data->supplies), data->supplies);
 914         if (ret)
 915                 return ret;
 916         /* Must wait for Tpor time after initial power up */
 917         usleep_range(1000, 1100);
 918
 919         ret = devm_add_action_or_reset(dev, sx9310_regulator_disable, data);
 920         if (ret)
 921                 return ret;
 922
 923         ret = regmap_read(data->regmap, SX9310_REG_WHOAMI, &data->whoami);
 924         if (ret) {
 925                 dev_err(dev, "error in reading WHOAMI register: %d", ret);
 926                 return ret;
 927         }
 928
 929         ret = sx9310_set_indio_dev_name(dev, indio_dev, data->whoami);
 930         if (ret)
 931                 return ret;
 932
 933         ACPI_COMPANION_SET(&indio_dev->dev, ACPI_COMPANION(dev));
 934         indio_dev->channels = sx9310_channels;
 935         indio_dev->num_channels = ARRAY_SIZE(sx9310_channels);
 936         indio_dev->info = &sx9310_info;
 937         indio_dev->modes = INDIO_DIRECT_MODE;
 938         i2c_set_clientdata(client, indio_dev);
 939
 940         ret = sx9310_init_device(indio_dev);
 941         if (ret)
 942                 return ret;
 943
 944         if (client->irq) {
 945                 ret = devm_request_threaded_irq(dev, client->irq,
 946                                                 sx9310_irq_handler,
 947                                                 sx9310_irq_thread_handler,
 948                                                 IRQF_ONESHOT,
 949                                                 "sx9310_event", indio_dev);
 950                 if (ret)
 951                         return ret;
 952
 953                 data->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
 954                                                     indio_dev->name,
 955                                                     indio_dev->id);
 956                 if (!data->trig)
 957                         return -ENOMEM;
 958
 959                 data->trig->dev.parent = dev;
 960                 data->trig->ops = &sx9310_trigger_ops;
 961                 iio_trigger_set_drvdata(data->trig, indio_dev);
 962
 963                 ret = devm_iio_trigger_register(dev, data->trig);
 964                 if (ret)
 965                         return ret;
 966         }
 967
 968         ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
 969                                               iio_pollfunc_store_time,
 970                                               sx9310_trigger_handler,
 971                                               &sx9310_buffer_setup_ops);
 972         if (ret)
 973                 return ret;
 974
 975         return devm_iio_device_register(dev, indio_dev);
 976 }
 977
 978 static int __maybe_unused sx9310_suspend(struct device *dev)
 979 {
 980         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 981         struct sx9310_data *data = iio_priv(indio_dev);
 982         u8 ctrl0;
 983         int ret;
 984
 985         disable_irq_nosync(data->client->irq);
 986
 987         mutex_lock(&data->mutex);
 988         ret = regmap_read(data->regmap, SX9310_REG_PROX_CTRL0,
 989                           &data->suspend_ctrl0);
 990         if (ret)
 991                 goto out;
 992
 993         ctrl0 = data->suspend_ctrl0 & ~SX9310_REG_PROX_CTRL0_SENSOREN_MASK;
 994         ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0, ctrl0);
 995         if (ret)
 996                 goto out;
 997
 998         ret = regmap_write(data->regmap, SX9310_REG_PAUSE, 0);
 999
1000 out:
1001         mutex_unlock(&data->mutex);
1002         return ret;
1003 }
1004
1005 static int __maybe_unused sx9310_resume(struct device *dev)
1006 {
1007         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
1008         struct sx9310_data *data = iio_priv(indio_dev);
1009         int ret;
1010
1011         mutex_lock(&data->mutex);
1012         ret = regmap_write(data->regmap, SX9310_REG_PAUSE, 1);
1013         if (ret)
1014                 goto out;
1015
1016         ret = regmap_write(data->regmap, SX9310_REG_PROX_CTRL0,
1017                            data->suspend_ctrl0);
1018
1019 out:
1020         mutex_unlock(&data->mutex);
1021         if (ret)
1022                 return ret;
1023
1024         enable_irq(data->client->irq);
1025         return 0;
1026 }
1027
1028 static const struct dev_pm_ops sx9310_pm_ops = {
1029         SET_SYSTEM_SLEEP_PM_OPS(sx9310_suspend, sx9310_resume)
1030 };
1031
1032 static const struct acpi_device_id sx9310_acpi_match[] = {
1033         { "STH9310", SX9310_WHOAMI_VALUE },
1034         { "STH9311", SX9311_WHOAMI_VALUE },
1035         {}
1036 };
1037 MODULE_DEVICE_TABLE(acpi, sx9310_acpi_match);
1038
1039 static const struct of_device_id sx9310_of_match[] = {
1040         { .compatible = "semtech,sx9310", (void *)SX9310_WHOAMI_VALUE },
1041         { .compatible = "semtech,sx9311", (void *)SX9311_WHOAMI_VALUE },
1042         {}
1043 };
1044 MODULE_DEVICE_TABLE(of, sx9310_of_match);
1045
1046 static const struct i2c_device_id sx9310_id[] = {
1047         { "sx9310", SX9310_WHOAMI_VALUE },
1048         { "sx9311", SX9311_WHOAMI_VALUE },
1049         {}
1050 };
1051 MODULE_DEVICE_TABLE(i2c, sx9310_id);
1052
1053 static struct i2c_driver sx9310_driver = {
1054         .driver = {
1055                 .name   = "sx9310",
1056                 .acpi_match_table = sx9310_acpi_match,
1057                 .of_match_table = sx9310_of_match,
1058                 .pm = &sx9310_pm_ops,
1059
1060                 /*
1061                  * Lots of i2c transfers in probe + over 200 ms waiting in
1062                  * sx9310_init_compensation() mean a slow probe; prefer async
1063                  * so we don't delay boot if we're builtin to the kernel.
1064                  */
1065                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1066         },
1067         .probe_new      = sx9310_probe,
1068         .id_table       = sx9310_id,
1069 };
1070 module_i2c_driver(sx9310_driver);
1071
1072 MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
1073 MODULE_AUTHOR("Daniel Campello <campello@chromium.org>");
1074 MODULE_DESCRIPTION("Driver for Semtech SX9310/SX9311 proximity sensor");
1075 MODULE_LICENSE("GPL v2");