drivers/iio/accel/stk8312.c

   1 /**
   2  * Sensortek STK8312 3-Axis Accelerometer
   3  *
   4  * Copyright (c) 2015, Intel Corporation.
   5  *
   6  * This file is subject to the terms and conditions of version 2 of
   7  * the GNU General Public License. See the file COPYING in the main
   8  * directory of this archive for more details.
   9  *
  10  * IIO driver for STK8312; 7-bit I2C address: 0x3D.
  11  */
  12
  13 #include <linux/acpi.h>
  14 #include <linux/gpio/consumer.h>
  15 #include <linux/i2c.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/delay.h>
  20 #include <linux/iio/buffer.h>
  21 #include <linux/iio/iio.h>
  22 #include <linux/iio/sysfs.h>
  23 #include <linux/iio/trigger.h>
  24 #include <linux/iio/triggered_buffer.h>
  25 #include <linux/iio/trigger_consumer.h>
  26
  27 #define STK8312_REG_XOUT                0x00
  28 #define STK8312_REG_YOUT                0x01
  29 #define STK8312_REG_ZOUT                0x02
  30 #define STK8312_REG_INTSU               0x06
  31 #define STK8312_REG_MODE                0x07
  32 #define STK8312_REG_SR                  0x08
  33 #define STK8312_REG_STH                 0x13
  34 #define STK8312_REG_RESET               0x20
  35 #define STK8312_REG_AFECTRL             0x24
  36 #define STK8312_REG_OTPADDR             0x3D
  37 #define STK8312_REG_OTPDATA             0x3E
  38 #define STK8312_REG_OTPCTRL             0x3F
  39
  40 #define STK8312_MODE_ACTIVE             BIT(0)
  41 #define STK8312_MODE_STANDBY            0x00
  42 #define STK8312_MODE_INT_AH_PP          0xC0    /* active-high, push-pull */
  43 #define STK8312_DREADY_BIT              BIT(4)
  44 #define STK8312_RNG_6G                  1
  45 #define STK8312_RNG_SHIFT               6
  46 #define STK8312_RNG_MASK                GENMASK(7, 6)
  47 #define STK8312_SR_MASK                 GENMASK(2, 0)
  48 #define STK8312_SR_400HZ_IDX            0
  49 #define STK8312_ALL_CHANNEL_MASK        GENMASK(2, 0)
  50 #define STK8312_ALL_CHANNEL_SIZE        3
  51
  52 #define STK8312_DRIVER_NAME             "stk8312"
  53 #define STK8312_GPIO                    "stk8312_gpio"
  54 #define STK8312_IRQ_NAME                "stk8312_event"
  55
  56 /*
  57  * The accelerometer has two measurement ranges:
  58  *
  59  * -6g - +6g (8-bit, signed)
  60  * -16g - +16g (8-bit, signed)
  61  *
  62  * scale1 = (6 + 6) * 9.81 / (2^8 - 1)     = 0.4616
  63  * scale2 = (16 + 16) * 9.81 / (2^8 - 1)   = 1.2311
  64  */
  65 #define STK8312_SCALE_AVAIL             "0.4616 1.2311"
  66
  67 static const int stk8312_scale_table[][2] = {
  68         {0, 461600}, {1, 231100}
  69 };
  70
  71 static const struct {
  72         int val;
  73         int val2;
  74 } stk8312_samp_freq_table[] = {
  75         {400, 0}, {200, 0}, {100, 0}, {50, 0}, {25, 0},
  76         {12, 500000}, {6, 250000}, {3, 125000}
  77 };
  78
  79 #define STK8312_ACCEL_CHANNEL(index, reg, axis) {                       \
  80         .type = IIO_ACCEL,                                              \
  81         .address = reg,                                                 \
  82         .modified = 1,                                                  \
  83         .channel2 = IIO_MOD_##axis,                                     \
  84         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),                   \
  85         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |          \
  86                                     BIT(IIO_CHAN_INFO_SAMP_FREQ),       \
  87         .scan_index = index,                                            \
  88         .scan_type = {                                                  \
  89                 .sign = 's',                                            \
  90                 .realbits = 8,                                          \
  91                 .storagebits = 8,                                       \
  92                 .endianness = IIO_CPU,                                  \
  93         },                                                              \
  94 }
  95
  96 static const struct iio_chan_spec stk8312_channels[] = {
  97         STK8312_ACCEL_CHANNEL(0, STK8312_REG_XOUT, X),
  98         STK8312_ACCEL_CHANNEL(1, STK8312_REG_YOUT, Y),
  99         STK8312_ACCEL_CHANNEL(2, STK8312_REG_ZOUT, Z),
 100         IIO_CHAN_SOFT_TIMESTAMP(3),
 101 };
 102
 103 struct stk8312_data {
 104         struct i2c_client *client;
 105         struct mutex lock;
 106         u8 range;
 107         u8 sample_rate_idx;
 108         u8 mode;
 109         struct iio_trigger *dready_trig;
 110         bool dready_trigger_on;
 111         s8 buffer[16]; /* 3x8-bit channels + 5x8 padding + 64-bit timestamp */
 112 };
 113
 114 static IIO_CONST_ATTR(in_accel_scale_available, STK8312_SCALE_AVAIL);
 115
 116 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("3.125 6.25 12.5 25 50 100 200 400");
 117
 118 static struct attribute *stk8312_attributes[] = {
 119         &iio_const_attr_in_accel_scale_available.dev_attr.attr,
 120         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 121         NULL,
 122 };
 123
 124 static const struct attribute_group stk8312_attribute_group = {
 125         .attrs = stk8312_attributes
 126 };
 127
 128 static int stk8312_otp_init(struct stk8312_data *data)
 129 {
 130         int ret;
 131         int count = 10;
 132         struct i2c_client *client = data->client;
 133
 134         ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPADDR, 0x70);
 135         if (ret < 0)
 136                 goto exit_err;
 137         ret = i2c_smbus_write_byte_data(client, STK8312_REG_OTPCTRL, 0x02);
 138         if (ret < 0)
 139                 goto exit_err;
 140
 141         do {
 142                 usleep_range(1000, 5000);
 143                 ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPCTRL);
 144                 if (ret < 0)
 145                         goto exit_err;
 146                 count--;
 147         } while (!(ret & BIT(7)) && count > 0);
 148
 149         if (count == 0) {
 150                 ret = -ETIMEDOUT;
 151                 goto exit_err;
 152         }
 153
 154         ret = i2c_smbus_read_byte_data(client, STK8312_REG_OTPDATA);
 155         if (ret == 0)
 156                 ret = -EINVAL;
 157         if (ret < 0)
 158                 goto exit_err;
 159
 160         ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_AFECTRL, ret);
 161         if (ret < 0)
 162                 goto exit_err;
 163         msleep(150);
 164
 165         return 0;
 166
 167 exit_err:
 168         dev_err(&client->dev, "failed to initialize sensor\n");
 169         return ret;
 170 }
 171
 172 static int stk8312_set_mode(struct stk8312_data *data, u8 mode)
 173 {
 174         int ret;
 175         struct i2c_client *client = data->client;
 176
 177         if (mode == data->mode)
 178                 return 0;
 179
 180         ret = i2c_smbus_write_byte_data(client, STK8312_REG_MODE, mode);
 181         if (ret < 0) {
 182                 dev_err(&client->dev, "failed to change sensor mode\n");
 183                 return ret;
 184         }
 185
 186         data->mode = mode;
 187         if (mode & STK8312_MODE_ACTIVE) {
 188                 /* Need to run OTP sequence before entering active mode */
 189                 usleep_range(1000, 5000);
 190                 ret = stk8312_otp_init(data);
 191         }
 192
 193         return ret;
 194 }
 195
 196 static int stk8312_set_interrupts(struct stk8312_data *data, u8 int_mask)
 197 {
 198         int ret;
 199         u8 mode;
 200         struct i2c_client *client = data->client;
 201
 202         mode = data->mode;
 203         /* We need to go in standby mode to modify registers */
 204         ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
 205         if (ret < 0)
 206                 return ret;
 207
 208         ret = i2c_smbus_write_byte_data(client, STK8312_REG_INTSU, int_mask);
 209         if (ret < 0) {
 210                 dev_err(&client->dev, "failed to set interrupts\n");
 211                 stk8312_set_mode(data, mode);
 212                 return ret;
 213         }
 214
 215         return stk8312_set_mode(data, mode);
 216 }
 217
 218 static int stk8312_data_rdy_trigger_set_state(struct iio_trigger *trig,
 219                                               bool state)
 220 {
 221         struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
 222         struct stk8312_data *data = iio_priv(indio_dev);
 223         int ret;
 224
 225         if (state)
 226                 ret = stk8312_set_interrupts(data, STK8312_DREADY_BIT);
 227         else
 228                 ret = stk8312_set_interrupts(data, 0x00);
 229
 230         if (ret < 0) {
 231                 dev_err(&data->client->dev, "failed to set trigger state\n");
 232                 return ret;
 233         }
 234
 235         data->dready_trigger_on = state;
 236
 237         return 0;
 238 }
 239
 240 static const struct iio_trigger_ops stk8312_trigger_ops = {
 241         .set_trigger_state = stk8312_data_rdy_trigger_set_state,
 242         .owner = THIS_MODULE,
 243 };
 244
 245 static int stk8312_set_sample_rate(struct stk8312_data *data, u8 rate)
 246 {
 247         int ret;
 248         u8 masked_reg;
 249         u8 mode;
 250         struct i2c_client *client = data->client;
 251
 252         if (rate == data->sample_rate_idx)
 253                 return 0;
 254
 255         mode = data->mode;
 256         /* We need to go in standby mode to modify registers */
 257         ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
 258         if (ret < 0)
 259                 return ret;
 260
 261         ret = i2c_smbus_read_byte_data(client, STK8312_REG_SR);
 262         if (ret < 0)
 263                 goto err_activate;
 264
 265         masked_reg = (ret & (~STK8312_SR_MASK)) | rate;
 266
 267         ret = i2c_smbus_write_byte_data(client, STK8312_REG_SR, masked_reg);
 268         if (ret < 0)
 269                 goto err_activate;
 270
 271         data->sample_rate_idx = rate;
 272
 273         return stk8312_set_mode(data, mode);
 274
 275 err_activate:
 276         dev_err(&client->dev, "failed to set sampling rate\n");
 277         stk8312_set_mode(data, mode);
 278
 279         return ret;
 280 }
 281
 282 static int stk8312_set_range(struct stk8312_data *data, u8 range)
 283 {
 284         int ret;
 285         u8 masked_reg;
 286         u8 mode;
 287         struct i2c_client *client = data->client;
 288
 289         if (range != 1 && range != 2)
 290                 return -EINVAL;
 291         else if (range == data->range)
 292                 return 0;
 293
 294         mode = data->mode;
 295         /* We need to go in standby mode to modify registers */
 296         ret = stk8312_set_mode(data, STK8312_MODE_STANDBY);
 297         if (ret < 0)
 298                 return ret;
 299
 300         ret = i2c_smbus_read_byte_data(client, STK8312_REG_STH);
 301         if (ret < 0)
 302                 goto err_activate;
 303
 304         masked_reg = ret & (~STK8312_RNG_MASK);
 305         masked_reg |= range << STK8312_RNG_SHIFT;
 306
 307         ret = i2c_smbus_write_byte_data(client, STK8312_REG_STH, masked_reg);
 308         if (ret < 0)
 309                 goto err_activate;
 310
 311         data->range = range;
 312
 313         return stk8312_set_mode(data, mode);
 314
 315 err_activate:
 316         dev_err(&client->dev, "failed to change sensor range\n");
 317         stk8312_set_mode(data, mode);
 318
 319         return ret;
 320 }
 321
 322 static int stk8312_read_accel(struct stk8312_data *data, u8 address)
 323 {
 324         int ret;
 325         struct i2c_client *client = data->client;
 326
 327         if (address > 2)
 328                 return -EINVAL;
 329
 330         ret = i2c_smbus_read_byte_data(client, address);
 331         if (ret < 0)
 332                 dev_err(&client->dev, "register read failed\n");
 333
 334         return ret;
 335 }
 336
 337 static int stk8312_read_raw(struct iio_dev *indio_dev,
 338                             struct iio_chan_spec const *chan,
 339                             int *val, int *val2, long mask)
 340 {
 341         struct stk8312_data *data = iio_priv(indio_dev);
 342         int ret;
 343
 344         switch (mask) {
 345         case IIO_CHAN_INFO_RAW:
 346                 if (iio_buffer_enabled(indio_dev))
 347                         return -EBUSY;
 348                 mutex_lock(&data->lock);
 349                 ret = stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
 350                 if (ret < 0) {
 351                         mutex_unlock(&data->lock);
 352                         return ret;
 353                 }
 354                 ret = stk8312_read_accel(data, chan->address);
 355                 if (ret < 0) {
 356                         stk8312_set_mode(data,
 357                                          data->mode & (~STK8312_MODE_ACTIVE));
 358                         mutex_unlock(&data->lock);
 359                         return ret;
 360                 }
 361                 *val = sign_extend32(ret, 7);
 362                 ret = stk8312_set_mode(data,
 363                                        data->mode & (~STK8312_MODE_ACTIVE));
 364                 mutex_unlock(&data->lock);
 365                 if (ret < 0)
 366                         return ret;
 367                 return IIO_VAL_INT;
 368         case IIO_CHAN_INFO_SCALE:
 369                 *val = stk8312_scale_table[data->range - 1][0];
 370                 *val2 = stk8312_scale_table[data->range - 1][1];
 371                 return IIO_VAL_INT_PLUS_MICRO;
 372         case IIO_CHAN_INFO_SAMP_FREQ:
 373                 *val = stk8312_samp_freq_table[data->sample_rate_idx].val;
 374                 *val2 = stk8312_samp_freq_table[data->sample_rate_idx].val2;
 375                 return IIO_VAL_INT_PLUS_MICRO;
 376         }
 377
 378         return -EINVAL;
 379 }
 380
 381 static int stk8312_write_raw(struct iio_dev *indio_dev,
 382                              struct iio_chan_spec const *chan,
 383                              int val, int val2, long mask)
 384 {
 385         int i;
 386         int index = -1;
 387         int ret;
 388         struct stk8312_data *data = iio_priv(indio_dev);
 389
 390         switch (mask) {
 391         case IIO_CHAN_INFO_SCALE:
 392                 for (i = 0; i < ARRAY_SIZE(stk8312_scale_table); i++)
 393                         if (val == stk8312_scale_table[i][0] &&
 394                             val2 == stk8312_scale_table[i][1]) {
 395                                 index = i + 1;
 396                                 break;
 397                         }
 398                 if (index < 0)
 399                         return -EINVAL;
 400
 401                 mutex_lock(&data->lock);
 402                 ret = stk8312_set_range(data, index);
 403                 mutex_unlock(&data->lock);
 404
 405                 return ret;
 406         case IIO_CHAN_INFO_SAMP_FREQ:
 407                 for (i = 0; i < ARRAY_SIZE(stk8312_samp_freq_table); i++)
 408                         if (val == stk8312_samp_freq_table[i].val &&
 409                             val2 == stk8312_samp_freq_table[i].val2) {
 410                                 index = i;
 411                                 break;
 412                         }
 413                 if (index < 0)
 414                         return -EINVAL;
 415                 mutex_lock(&data->lock);
 416                 ret = stk8312_set_sample_rate(data, index);
 417                 mutex_unlock(&data->lock);
 418
 419                 return ret;
 420         }
 421
 422         return -EINVAL;
 423 }
 424
 425 static const struct iio_info stk8312_info = {
 426         .driver_module          = THIS_MODULE,
 427         .read_raw               = stk8312_read_raw,
 428         .write_raw              = stk8312_write_raw,
 429         .attrs                  = &stk8312_attribute_group,
 430 };
 431
 432 static irqreturn_t stk8312_trigger_handler(int irq, void *p)
 433 {
 434         struct iio_poll_func *pf = p;
 435         struct iio_dev *indio_dev = pf->indio_dev;
 436         struct stk8312_data *data = iio_priv(indio_dev);
 437         int bit, ret, i = 0;
 438
 439         mutex_lock(&data->lock);
 440         /*
 441          * Do a bulk read if all channels are requested,
 442          * from 0x00 (XOUT) to 0x02 (ZOUT)
 443          */
 444         if (*(indio_dev->active_scan_mask) == STK8312_ALL_CHANNEL_MASK) {
 445                 ret = i2c_smbus_read_i2c_block_data(data->client,
 446                                                     STK8312_REG_XOUT,
 447                                                     STK8312_ALL_CHANNEL_SIZE,
 448                                                     data->buffer);
 449                 if (ret < STK8312_ALL_CHANNEL_SIZE) {
 450                         dev_err(&data->client->dev, "register read failed\n");
 451                         mutex_unlock(&data->lock);
 452                         goto err;
 453                 }
 454         } else {
 455                 for_each_set_bit(bit, indio_dev->active_scan_mask,
 456                                  indio_dev->masklength) {
 457                         ret = stk8312_read_accel(data, bit);
 458                         if (ret < 0) {
 459                                 mutex_unlock(&data->lock);
 460                                 goto err;
 461                         }
 462                         data->buffer[i++] = ret;
 463                 }
 464         }
 465         mutex_unlock(&data->lock);
 466
 467         iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
 468                                            pf->timestamp);
 469 err:
 470         iio_trigger_notify_done(indio_dev->trig);
 471
 472         return IRQ_HANDLED;
 473 }
 474
 475 static irqreturn_t stk8312_data_rdy_trig_poll(int irq, void *private)
 476 {
 477         struct iio_dev *indio_dev = private;
 478         struct stk8312_data *data = iio_priv(indio_dev);
 479
 480         if (data->dready_trigger_on)
 481                 iio_trigger_poll(data->dready_trig);
 482
 483         return IRQ_HANDLED;
 484 }
 485
 486 static int stk8312_buffer_preenable(struct iio_dev *indio_dev)
 487 {
 488         struct stk8312_data *data = iio_priv(indio_dev);
 489
 490         return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
 491 }
 492
 493 static int stk8312_buffer_postdisable(struct iio_dev *indio_dev)
 494 {
 495         struct stk8312_data *data = iio_priv(indio_dev);
 496
 497         return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
 498 }
 499
 500 static const struct iio_buffer_setup_ops stk8312_buffer_setup_ops = {
 501         .preenable   = stk8312_buffer_preenable,
 502         .postenable  = iio_triggered_buffer_postenable,
 503         .predisable  = iio_triggered_buffer_predisable,
 504         .postdisable = stk8312_buffer_postdisable,
 505 };
 506
 507 static int stk8312_gpio_probe(struct i2c_client *client)
 508 {
 509         struct device *dev;
 510         struct gpio_desc *gpio;
 511         int ret;
 512
 513         if (!client)
 514                 return -EINVAL;
 515
 516         dev = &client->dev;
 517
 518         /* data ready gpio interrupt pin */
 519         gpio = devm_gpiod_get_index(dev, STK8312_GPIO, 0, GPIOD_IN);
 520         if (IS_ERR(gpio)) {
 521                 dev_err(dev, "acpi gpio get index failed\n");
 522                 return PTR_ERR(gpio);
 523         }
 524
 525         ret = gpiod_to_irq(gpio);
 526         dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
 527
 528         return ret;
 529 }
 530
 531 static int stk8312_probe(struct i2c_client *client,
 532                          const struct i2c_device_id *id)
 533 {
 534         int ret;
 535         struct iio_dev *indio_dev;
 536         struct stk8312_data *data;
 537
 538         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 539         if (!indio_dev) {
 540                 dev_err(&client->dev, "iio allocation failed!\n");
 541                 return -ENOMEM;
 542         }
 543
 544         data = iio_priv(indio_dev);
 545         data->client = client;
 546         i2c_set_clientdata(client, indio_dev);
 547         mutex_init(&data->lock);
 548
 549         indio_dev->dev.parent = &client->dev;
 550         indio_dev->info = &stk8312_info;
 551         indio_dev->name = STK8312_DRIVER_NAME;
 552         indio_dev->modes = INDIO_DIRECT_MODE;
 553         indio_dev->channels = stk8312_channels;
 554         indio_dev->num_channels = ARRAY_SIZE(stk8312_channels);
 555
 556         /* A software reset is recommended at power-on */
 557         ret = i2c_smbus_write_byte_data(data->client, STK8312_REG_RESET, 0x00);
 558         if (ret < 0) {
 559                 dev_err(&client->dev, "failed to reset sensor\n");
 560                 return ret;
 561         }
 562         data->sample_rate_idx = STK8312_SR_400HZ_IDX;
 563         ret = stk8312_set_range(data, STK8312_RNG_6G);
 564         if (ret < 0)
 565                 return ret;
 566
 567         ret = stk8312_set_mode(data,
 568                                STK8312_MODE_INT_AH_PP | STK8312_MODE_ACTIVE);
 569         if (ret < 0)
 570                 return ret;
 571
 572         if (client->irq < 0)
 573                 client->irq = stk8312_gpio_probe(client);
 574
 575         if (client->irq >= 0) {
 576                 ret = devm_request_threaded_irq(&client->dev, client->irq,
 577                                                 stk8312_data_rdy_trig_poll,
 578                                                 NULL,
 579                                                 IRQF_TRIGGER_RISING |
 580                                                 IRQF_ONESHOT,
 581                                                 STK8312_IRQ_NAME,
 582                                                 indio_dev);
 583                 if (ret < 0) {
 584                         dev_err(&client->dev, "request irq %d failed\n",
 585                                 client->irq);
 586                         goto err_power_off;
 587                 }
 588
 589                 data->dready_trig = devm_iio_trigger_alloc(&client->dev,
 590                                                            "%s-dev%d",
 591                                                            indio_dev->name,
 592                                                            indio_dev->id);
 593                 if (!data->dready_trig) {
 594                         ret = -ENOMEM;
 595                         goto err_power_off;
 596                 }
 597
 598                 data->dready_trig->dev.parent = &client->dev;
 599                 data->dready_trig->ops = &stk8312_trigger_ops;
 600                 iio_trigger_set_drvdata(data->dready_trig, indio_dev);
 601                 ret = iio_trigger_register(data->dready_trig);
 602                 if (ret) {
 603                         dev_err(&client->dev, "iio trigger register failed\n");
 604                         goto err_power_off;
 605                 }
 606         }
 607
 608         ret = iio_triggered_buffer_setup(indio_dev,
 609                                          iio_pollfunc_store_time,
 610                                          stk8312_trigger_handler,
 611                                          &stk8312_buffer_setup_ops);
 612         if (ret < 0) {
 613                 dev_err(&client->dev, "iio triggered buffer setup failed\n");
 614                 goto err_trigger_unregister;
 615         }
 616
 617         ret = iio_device_register(indio_dev);
 618         if (ret < 0) {
 619                 dev_err(&client->dev, "device_register failed\n");
 620                 goto err_buffer_cleanup;
 621         }
 622
 623         return 0;
 624
 625 err_buffer_cleanup:
 626         iio_triggered_buffer_cleanup(indio_dev);
 627 err_trigger_unregister:
 628         if (data->dready_trig)
 629                 iio_trigger_unregister(data->dready_trig);
 630 err_power_off:
 631         stk8312_set_mode(data, STK8312_MODE_STANDBY);
 632         return ret;
 633 }
 634
 635 static int stk8312_remove(struct i2c_client *client)
 636 {
 637         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 638         struct stk8312_data *data = iio_priv(indio_dev);
 639
 640         iio_device_unregister(indio_dev);
 641         iio_triggered_buffer_cleanup(indio_dev);
 642
 643         if (data->dready_trig)
 644                 iio_trigger_unregister(data->dready_trig);
 645
 646         return stk8312_set_mode(data, STK8312_MODE_STANDBY);
 647 }
 648
 649 #ifdef CONFIG_PM_SLEEP
 650 static int stk8312_suspend(struct device *dev)
 651 {
 652         struct stk8312_data *data;
 653
 654         data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
 655
 656         return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE));
 657 }
 658
 659 static int stk8312_resume(struct device *dev)
 660 {
 661         struct stk8312_data *data;
 662
 663         data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
 664
 665         return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE);
 666 }
 667
 668 static SIMPLE_DEV_PM_OPS(stk8312_pm_ops, stk8312_suspend, stk8312_resume);
 669
 670 #define STK8312_PM_OPS (&stk8312_pm_ops)
 671 #else
 672 #define STK8312_PM_OPS NULL
 673 #endif
 674
 675 static const struct i2c_device_id stk8312_i2c_id[] = {
 676         {"STK8312", 0},
 677         {}
 678 };
 679 MODULE_DEVICE_TABLE(i2c, stk8312_i2c_id);
 680
 681 static const struct acpi_device_id stk8312_acpi_id[] = {
 682         {"STK8312", 0},
 683         {}
 684 };
 685
 686 MODULE_DEVICE_TABLE(acpi, stk8312_acpi_id);
 687
 688 static struct i2c_driver stk8312_driver = {
 689         .driver = {
 690                 .name = STK8312_DRIVER_NAME,
 691                 .pm = STK8312_PM_OPS,
 692                 .acpi_match_table = ACPI_PTR(stk8312_acpi_id),
 693         },
 694         .probe =            stk8312_probe,
 695         .remove =           stk8312_remove,
 696         .id_table =         stk8312_i2c_id,
 697 };
 698
 699 module_i2c_driver(stk8312_driver);
 700
 701 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
 702 MODULE_DESCRIPTION("STK8312 3-Axis Accelerometer driver");
 703 MODULE_LICENSE("GPL v2");