drivers/input/touchscreen/bu21013_ts.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) ST-Ericsson SA 2010
   4  * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
   5  */
   6
   7 #include <linux/bitops.h>
   8 #include <linux/delay.h>
   9 #include <linux/gpio/consumer.h>
  10 #include <linux/i2c.h>
  11 #include <linux/input.h>
  12 #include <linux/input/mt.h>
  13 #include <linux/input/touchscreen.h>
  14 #include <linux/interrupt.h>
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/property.h>
  18 #include <linux/regulator/consumer.h>
  19 #include <linux/slab.h>
  20 #include <linux/types.h>
  21
  22 #define MAX_FINGERS     2
  23 #define RESET_DELAY     30
  24 #define PENUP_TIMEOUT   (10)
  25 #define DELTA_MIN       16
  26 #define MASK_BITS       0x03
  27 #define SHIFT_8         8
  28 #define SHIFT_2         2
  29 #define LENGTH_OF_BUFFER        11
  30 #define I2C_RETRY_COUNT 5
  31
  32 #define BU21013_SENSORS_BTN_0_7_REG     0x70
  33 #define BU21013_SENSORS_BTN_8_15_REG    0x71
  34 #define BU21013_SENSORS_BTN_16_23_REG   0x72
  35 #define BU21013_X1_POS_MSB_REG          0x73
  36 #define BU21013_X1_POS_LSB_REG          0x74
  37 #define BU21013_Y1_POS_MSB_REG          0x75
  38 #define BU21013_Y1_POS_LSB_REG          0x76
  39 #define BU21013_X2_POS_MSB_REG          0x77
  40 #define BU21013_X2_POS_LSB_REG          0x78
  41 #define BU21013_Y2_POS_MSB_REG          0x79
  42 #define BU21013_Y2_POS_LSB_REG          0x7A
  43 #define BU21013_INT_CLR_REG             0xE8
  44 #define BU21013_INT_MODE_REG            0xE9
  45 #define BU21013_GAIN_REG                0xEA
  46 #define BU21013_OFFSET_MODE_REG         0xEB
  47 #define BU21013_XY_EDGE_REG             0xEC
  48 #define BU21013_RESET_REG               0xED
  49 #define BU21013_CALIB_REG               0xEE
  50 #define BU21013_DONE_REG                0xEF
  51 #define BU21013_SENSOR_0_7_REG          0xF0
  52 #define BU21013_SENSOR_8_15_REG         0xF1
  53 #define BU21013_SENSOR_16_23_REG        0xF2
  54 #define BU21013_POS_MODE1_REG           0xF3
  55 #define BU21013_POS_MODE2_REG           0xF4
  56 #define BU21013_CLK_MODE_REG            0xF5
  57 #define BU21013_IDLE_REG                0xFA
  58 #define BU21013_FILTER_REG              0xFB
  59 #define BU21013_TH_ON_REG               0xFC
  60 #define BU21013_TH_OFF_REG              0xFD
  61
  62
  63 #define BU21013_RESET_ENABLE            0x01
  64
  65 #define BU21013_SENSORS_EN_0_7          0x3F
  66 #define BU21013_SENSORS_EN_8_15         0xFC
  67 #define BU21013_SENSORS_EN_16_23        0x1F
  68
  69 #define BU21013_POS_MODE1_0             0x02
  70 #define BU21013_POS_MODE1_1             0x04
  71 #define BU21013_POS_MODE1_2             0x08
  72
  73 #define BU21013_POS_MODE2_ZERO          0x01
  74 #define BU21013_POS_MODE2_AVG1          0x02
  75 #define BU21013_POS_MODE2_AVG2          0x04
  76 #define BU21013_POS_MODE2_EN_XY         0x08
  77 #define BU21013_POS_MODE2_EN_RAW        0x10
  78 #define BU21013_POS_MODE2_MULTI         0x80
  79
  80 #define BU21013_CLK_MODE_DIV            0x01
  81 #define BU21013_CLK_MODE_EXT            0x02
  82 #define BU21013_CLK_MODE_CALIB          0x80
  83
  84 #define BU21013_IDLET_0                 0x01
  85 #define BU21013_IDLET_1                 0x02
  86 #define BU21013_IDLET_2                 0x04
  87 #define BU21013_IDLET_3                 0x08
  88 #define BU21013_IDLE_INTERMIT_EN        0x10
  89
  90 #define BU21013_DELTA_0_6       0x7F
  91 #define BU21013_FILTER_EN       0x80
  92
  93 #define BU21013_INT_MODE_LEVEL  0x00
  94 #define BU21013_INT_MODE_EDGE   0x01
  95
  96 #define BU21013_GAIN_0          0x01
  97 #define BU21013_GAIN_1          0x02
  98 #define BU21013_GAIN_2          0x04
  99
 100 #define BU21013_OFFSET_MODE_DEFAULT     0x00
 101 #define BU21013_OFFSET_MODE_MOVE        0x01
 102 #define BU21013_OFFSET_MODE_DISABLE     0x02
 103
 104 #define BU21013_TH_ON_0         0x01
 105 #define BU21013_TH_ON_1         0x02
 106 #define BU21013_TH_ON_2         0x04
 107 #define BU21013_TH_ON_3         0x08
 108 #define BU21013_TH_ON_4         0x10
 109 #define BU21013_TH_ON_5         0x20
 110 #define BU21013_TH_ON_6         0x40
 111 #define BU21013_TH_ON_7         0x80
 112 #define BU21013_TH_ON_MAX       0xFF
 113
 114 #define BU21013_TH_OFF_0        0x01
 115 #define BU21013_TH_OFF_1        0x02
 116 #define BU21013_TH_OFF_2        0x04
 117 #define BU21013_TH_OFF_3        0x08
 118 #define BU21013_TH_OFF_4        0x10
 119 #define BU21013_TH_OFF_5        0x20
 120 #define BU21013_TH_OFF_6        0x40
 121 #define BU21013_TH_OFF_7        0x80
 122 #define BU21013_TH_OFF_MAX      0xFF
 123
 124 #define BU21013_X_EDGE_0        0x01
 125 #define BU21013_X_EDGE_1        0x02
 126 #define BU21013_X_EDGE_2        0x04
 127 #define BU21013_X_EDGE_3        0x08
 128 #define BU21013_Y_EDGE_0        0x10
 129 #define BU21013_Y_EDGE_1        0x20
 130 #define BU21013_Y_EDGE_2        0x40
 131 #define BU21013_Y_EDGE_3        0x80
 132
 133 #define BU21013_DONE    0x01
 134 #define BU21013_NUMBER_OF_X_SENSORS     (6)
 135 #define BU21013_NUMBER_OF_Y_SENSORS     (11)
 136
 137 #define DRIVER_TP       "bu21013_tp"
 138
 139 /**
 140  * struct bu21013_ts - touch panel data structure
 141  * @client: pointer to the i2c client
 142  * @in_dev: pointer to the input device structure
 143  * @props: the device coordinate transformation properties
 144  * @regulator: pointer to the Regulator used for touch screen
 145  * @cs_gpiod: chip select GPIO line
 146  * @int_gpiod: touch interrupt GPIO line
 147  * @touch_x_max: maximum X coordinate reported by the device
 148  * @touch_y_max: maximum Y coordinate reported by the device
 149  * @x_flip: indicates that the driver should invert X coordinate before
 150  *      reporting
 151  * @y_flip: indicates that the driver should invert Y coordinate before
 152  *      reporting
 153  * @touch_stopped: touch stop flag
 154  *
 155  * Touch panel device data structure
 156  */
 157 struct bu21013_ts {
 158         struct i2c_client *client;
 159         struct input_dev *in_dev;
 160         struct touchscreen_properties props;
 161         struct regulator *regulator;
 162         struct gpio_desc *cs_gpiod;
 163         struct gpio_desc *int_gpiod;
 164         u32 touch_x_max;
 165         u32 touch_y_max;
 166         bool x_flip;
 167         bool y_flip;
 168         bool touch_stopped;
 169 };
 170
 171 static int bu21013_read_block_data(struct bu21013_ts *ts, u8 *buf)
 172 {
 173         int ret, i;
 174
 175         for (i = 0; i < I2C_RETRY_COUNT; i++) {
 176                 ret = i2c_smbus_read_i2c_block_data(ts->client,
 177                                                     BU21013_SENSORS_BTN_0_7_REG,
 178                                                     LENGTH_OF_BUFFER, buf);
 179                 if (ret == LENGTH_OF_BUFFER)
 180                         return 0;
 181         }
 182
 183         return -EINVAL;
 184 }
 185
 186 static int bu21013_do_touch_report(struct bu21013_ts *ts)
 187 {
 188         struct input_dev *input = ts->in_dev;
 189         struct input_mt_pos pos[MAX_FINGERS];
 190         int slots[MAX_FINGERS];
 191         u8 buf[LENGTH_OF_BUFFER];
 192         bool has_x_sensors, has_y_sensors;
 193         int finger_down_count = 0;
 194         int i;
 195
 196         if (bu21013_read_block_data(ts, buf) < 0)
 197                 return -EINVAL;
 198
 199         has_x_sensors = hweight32(buf[0] & BU21013_SENSORS_EN_0_7);
 200         has_y_sensors = hweight32(((buf[1] & BU21013_SENSORS_EN_8_15) |
 201                 ((buf[2] & BU21013_SENSORS_EN_16_23) << SHIFT_8)) >> SHIFT_2);
 202         if (!has_x_sensors || !has_y_sensors)
 203                 return 0;
 204
 205         for (i = 0; i < MAX_FINGERS; i++) {
 206                 const u8 *data = &buf[4 * i + 3];
 207                 unsigned int x, y;
 208
 209                 x = data[0] << SHIFT_2 | (data[1] & MASK_BITS);
 210                 y = data[2] << SHIFT_2 | (data[3] & MASK_BITS);
 211                 if (x != 0 && y != 0)
 212                         touchscreen_set_mt_pos(&pos[finger_down_count++],
 213                                                &ts->props, x, y);
 214         }
 215
 216         if (finger_down_count == 2 &&
 217             (abs(pos[0].x - pos[1].x) < DELTA_MIN ||
 218              abs(pos[0].y - pos[1].y) < DELTA_MIN)) {
 219                 return 0;
 220         }
 221
 222         input_mt_assign_slots(input, slots, pos, finger_down_count, DELTA_MIN);
 223         for (i = 0; i < finger_down_count; i++) {
 224                 input_mt_slot(input, slots[i]);
 225                 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
 226                 input_report_abs(input, ABS_MT_POSITION_X, pos[i].x);
 227                 input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y);
 228         }
 229
 230         input_mt_sync_frame(input);
 231         input_sync(input);
 232
 233         return 0;
 234 }
 235
 236 static irqreturn_t bu21013_gpio_irq(int irq, void *device_data)
 237 {
 238         struct bu21013_ts *ts = device_data;
 239         int keep_polling;
 240         int error;
 241
 242         do {
 243                 error = bu21013_do_touch_report(ts);
 244                 if (error) {
 245                         dev_err(&ts->client->dev, "%s failed\n", __func__);
 246                         break;
 247                 }
 248
 249                 if (unlikely(ts->touch_stopped))
 250                         break;
 251
 252                 keep_polling = ts->int_gpiod ?
 253                         gpiod_get_value(ts->int_gpiod) : false;
 254                 if (keep_polling)
 255                         usleep_range(2000, 2500);
 256         } while (keep_polling);
 257
 258         return IRQ_HANDLED;
 259 }
 260
 261 static int bu21013_init_chip(struct bu21013_ts *ts)
 262 {
 263         struct i2c_client *client = ts->client;
 264         int error;
 265
 266         error = i2c_smbus_write_byte_data(client, BU21013_RESET_REG,
 267                                           BU21013_RESET_ENABLE);
 268         if (error) {
 269                 dev_err(&client->dev, "BU21013_RESET reg write failed\n");
 270                 return error;
 271         }
 272         msleep(RESET_DELAY);
 273
 274         error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_0_7_REG,
 275                                           BU21013_SENSORS_EN_0_7);
 276         if (error) {
 277                 dev_err(&client->dev, "BU21013_SENSOR_0_7 reg write failed\n");
 278                 return error;
 279         }
 280
 281         error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_8_15_REG,
 282                                           BU21013_SENSORS_EN_8_15);
 283         if (error) {
 284                 dev_err(&client->dev, "BU21013_SENSOR_8_15 reg write failed\n");
 285                 return error;
 286         }
 287
 288         error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_16_23_REG,
 289                                           BU21013_SENSORS_EN_16_23);
 290         if (error) {
 291                 dev_err(&client->dev, "BU21013_SENSOR_16_23 reg write failed\n");
 292                 return error;
 293         }
 294
 295         error = i2c_smbus_write_byte_data(client, BU21013_POS_MODE1_REG,
 296                                           BU21013_POS_MODE1_0 |
 297                                                 BU21013_POS_MODE1_1);
 298         if (error) {
 299                 dev_err(&client->dev, "BU21013_POS_MODE1 reg write failed\n");
 300                 return error;
 301         }
 302
 303         error = i2c_smbus_write_byte_data(client, BU21013_POS_MODE2_REG,
 304                                           BU21013_POS_MODE2_ZERO |
 305                                                 BU21013_POS_MODE2_AVG1 |
 306                                                 BU21013_POS_MODE2_AVG2 |
 307                                                 BU21013_POS_MODE2_EN_RAW |
 308                                                 BU21013_POS_MODE2_MULTI);
 309         if (error) {
 310                 dev_err(&client->dev, "BU21013_POS_MODE2 reg write failed\n");
 311                 return error;
 312         }
 313
 314         error = i2c_smbus_write_byte_data(client, BU21013_CLK_MODE_REG,
 315                                           BU21013_CLK_MODE_DIV |
 316                                                 BU21013_CLK_MODE_CALIB);
 317         if (error) {
 318                 dev_err(&client->dev, "BU21013_CLK_MODE reg write failed\n");
 319                 return error;
 320         }
 321
 322         error = i2c_smbus_write_byte_data(client, BU21013_IDLE_REG,
 323                                           BU21013_IDLET_0 |
 324                                                 BU21013_IDLE_INTERMIT_EN);
 325         if (error) {
 326                 dev_err(&client->dev, "BU21013_IDLE reg write failed\n");
 327                 return error;
 328         }
 329
 330         error = i2c_smbus_write_byte_data(client, BU21013_INT_MODE_REG,
 331                                           BU21013_INT_MODE_LEVEL);
 332         if (error) {
 333                 dev_err(&client->dev, "BU21013_INT_MODE reg write failed\n");
 334                 return error;
 335         }
 336
 337         error = i2c_smbus_write_byte_data(client, BU21013_FILTER_REG,
 338                                           BU21013_DELTA_0_6 |
 339                                                 BU21013_FILTER_EN);
 340         if (error) {
 341                 dev_err(&client->dev, "BU21013_FILTER reg write failed\n");
 342                 return error;
 343         }
 344
 345         error = i2c_smbus_write_byte_data(client, BU21013_TH_ON_REG,
 346                                           BU21013_TH_ON_5);
 347         if (error) {
 348                 dev_err(&client->dev, "BU21013_TH_ON reg write failed\n");
 349                 return error;
 350         }
 351
 352         error = i2c_smbus_write_byte_data(client, BU21013_TH_OFF_REG,
 353                                           BU21013_TH_OFF_4 | BU21013_TH_OFF_3);
 354         if (error) {
 355                 dev_err(&client->dev, "BU21013_TH_OFF reg write failed\n");
 356                 return error;
 357         }
 358
 359         error = i2c_smbus_write_byte_data(client, BU21013_GAIN_REG,
 360                                           BU21013_GAIN_0 | BU21013_GAIN_1);
 361         if (error) {
 362                 dev_err(&client->dev, "BU21013_GAIN reg write failed\n");
 363                 return error;
 364         }
 365
 366         error = i2c_smbus_write_byte_data(client, BU21013_OFFSET_MODE_REG,
 367                                           BU21013_OFFSET_MODE_DEFAULT);
 368         if (error) {
 369                 dev_err(&client->dev, "BU21013_OFFSET_MODE reg write failed\n");
 370                 return error;
 371         }
 372
 373         error = i2c_smbus_write_byte_data(client, BU21013_XY_EDGE_REG,
 374                                           BU21013_X_EDGE_0 |
 375                                                 BU21013_X_EDGE_2 |
 376                                                 BU21013_Y_EDGE_1 |
 377                                                 BU21013_Y_EDGE_3);
 378         if (error) {
 379                 dev_err(&client->dev, "BU21013_XY_EDGE reg write failed\n");
 380                 return error;
 381         }
 382
 383         error = i2c_smbus_write_byte_data(client, BU21013_DONE_REG,
 384                                           BU21013_DONE);
 385         if (error) {
 386                 dev_err(&client->dev, "BU21013_REG_DONE reg write failed\n");
 387                 return error;
 388         }
 389
 390         return 0;
 391 }
 392
 393 static void bu21013_power_off(void *_ts)
 394 {
 395         struct bu21013_ts *ts = _ts;
 396
 397         regulator_disable(ts->regulator);
 398 }
 399
 400 static void bu21013_disable_chip(void *_ts)
 401 {
 402         struct bu21013_ts *ts = _ts;
 403
 404         gpiod_set_value(ts->cs_gpiod, 0);
 405 }
 406
 407 static int bu21013_probe(struct i2c_client *client,
 408                          const struct i2c_device_id *id)
 409 {
 410         struct bu21013_ts *ts;
 411         struct input_dev *in_dev;
 412         struct input_absinfo *info;
 413         u32 max_x = 0, max_y = 0;
 414         int error;
 415
 416         if (!i2c_check_functionality(client->adapter,
 417                                      I2C_FUNC_SMBUS_BYTE_DATA)) {
 418                 dev_err(&client->dev, "i2c smbus byte data not supported\n");
 419                 return -EIO;
 420         }
 421
 422         if (!client->irq) {
 423                 dev_err(&client->dev, "No IRQ set up\n");
 424                 return -EINVAL;
 425         }
 426
 427         ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
 428         if (!ts)
 429                 return -ENOMEM;
 430
 431         ts->client = client;
 432
 433         ts->x_flip = device_property_read_bool(&client->dev, "rohm,flip-x");
 434         ts->y_flip = device_property_read_bool(&client->dev, "rohm,flip-y");
 435
 436         in_dev = devm_input_allocate_device(&client->dev);
 437         if (!in_dev) {
 438                 dev_err(&client->dev, "device memory alloc failed\n");
 439                 return -ENOMEM;
 440         }
 441         ts->in_dev = in_dev;
 442         input_set_drvdata(in_dev, ts);
 443
 444         /* register the device to input subsystem */
 445         in_dev->name = DRIVER_TP;
 446         in_dev->id.bustype = BUS_I2C;
 447
 448         device_property_read_u32(&client->dev, "rohm,touch-max-x", &max_x);
 449         device_property_read_u32(&client->dev, "rohm,touch-max-y", &max_y);
 450
 451         input_set_abs_params(in_dev, ABS_MT_POSITION_X, 0, max_x, 0, 0);
 452         input_set_abs_params(in_dev, ABS_MT_POSITION_Y, 0, max_y, 0, 0);
 453
 454         touchscreen_parse_properties(in_dev, true, &ts->props);
 455
 456         /* Adjust for the legacy "flip" properties, if present */
 457         if (!ts->props.invert_x &&
 458             device_property_read_bool(&client->dev, "rohm,flip-x")) {
 459                 info = &in_dev->absinfo[ABS_MT_POSITION_X];
 460                 info->maximum -= info->minimum;
 461                 info->minimum = 0;
 462         }
 463
 464         if (!ts->props.invert_y &&
 465             device_property_read_bool(&client->dev, "rohm,flip-y")) {
 466                 info = &in_dev->absinfo[ABS_MT_POSITION_Y];
 467                 info->maximum -= info->minimum;
 468                 info->minimum = 0;
 469         }
 470
 471         error = input_mt_init_slots(in_dev, MAX_FINGERS,
 472                                     INPUT_MT_DIRECT | INPUT_MT_TRACK |
 473                                         INPUT_MT_DROP_UNUSED);
 474         if (error) {
 475                 dev_err(&client->dev, "failed to initialize MT slots");
 476                 return error;
 477         }
 478
 479         ts->regulator = devm_regulator_get(&client->dev, "avdd");
 480         if (IS_ERR(ts->regulator)) {
 481                 dev_err(&client->dev, "regulator_get failed\n");
 482                 return PTR_ERR(ts->regulator);
 483         }
 484
 485         error = regulator_enable(ts->regulator);
 486         if (error) {
 487                 dev_err(&client->dev, "regulator enable failed\n");
 488                 return error;
 489         }
 490
 491         error = devm_add_action_or_reset(&client->dev, bu21013_power_off, ts);
 492         if (error) {
 493                 dev_err(&client->dev, "failed to install power off handler\n");
 494                 return error;
 495         }
 496
 497         /* Named "CS" on the chip, DT binding is "reset" */
 498         ts->cs_gpiod = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_HIGH);
 499         error = PTR_ERR_OR_ZERO(ts->cs_gpiod);
 500         if (error) {
 501                 if (error != -EPROBE_DEFER)
 502                         dev_err(&client->dev, "failed to get CS GPIO\n");
 503                 return error;
 504         }
 505         gpiod_set_consumer_name(ts->cs_gpiod, "BU21013 CS");
 506
 507         error = devm_add_action_or_reset(&client->dev,
 508                                          bu21013_disable_chip, ts);
 509         if (error) {
 510                 dev_err(&client->dev,
 511                         "failed to install chip disable handler\n");
 512                 return error;
 513         }
 514
 515         /* Named "INT" on the chip, DT binding is "touch" */
 516         ts->int_gpiod = devm_gpiod_get_optional(&client->dev,
 517                                                 "touch", GPIOD_IN);
 518         error = PTR_ERR_OR_ZERO(ts->int_gpiod);
 519         if (error) {
 520                 if (error != -EPROBE_DEFER)
 521                         dev_err(&client->dev, "failed to get INT GPIO\n");
 522                 return error;
 523         }
 524
 525         if (ts->int_gpiod)
 526                 gpiod_set_consumer_name(ts->int_gpiod, "BU21013 INT");
 527
 528         /* configure the touch panel controller */
 529         error = bu21013_init_chip(ts);
 530         if (error) {
 531                 dev_err(&client->dev, "error in bu21013 config\n");
 532                 return error;
 533         }
 534
 535         error = devm_request_threaded_irq(&client->dev, client->irq,
 536                                           NULL, bu21013_gpio_irq,
 537                                           IRQF_ONESHOT, DRIVER_TP, ts);
 538         if (error) {
 539                 dev_err(&client->dev, "request irq %d failed\n",
 540                         client->irq);
 541                 return error;
 542         }
 543
 544         error = input_register_device(in_dev);
 545         if (error) {
 546                 dev_err(&client->dev, "failed to register input device\n");
 547                 return error;
 548         }
 549
 550         i2c_set_clientdata(client, ts);
 551
 552         return 0;
 553 }
 554
 555 static int bu21013_remove(struct i2c_client *client)
 556 {
 557         struct bu21013_ts *ts = i2c_get_clientdata(client);
 558
 559         /* Make sure IRQ will exit quickly even if there is contact */
 560         ts->touch_stopped = true;
 561         /* The resources will be freed by devm */
 562
 563         return 0;
 564 }
 565
 566 static int __maybe_unused bu21013_suspend(struct device *dev)
 567 {
 568         struct i2c_client *client = to_i2c_client(dev);
 569         struct bu21013_ts *ts = i2c_get_clientdata(client);
 570
 571         ts->touch_stopped = true;
 572         mb();
 573         disable_irq(client->irq);
 574
 575         if (!device_may_wakeup(&client->dev))
 576                 regulator_disable(ts->regulator);
 577
 578         return 0;
 579 }
 580
 581 static int __maybe_unused bu21013_resume(struct device *dev)
 582 {
 583         struct i2c_client *client = to_i2c_client(dev);
 584         struct bu21013_ts *ts = i2c_get_clientdata(client);
 585         int error;
 586
 587         if (!device_may_wakeup(&client->dev)) {
 588                 error = regulator_enable(ts->regulator);
 589                 if (error) {
 590                         dev_err(&client->dev,
 591                                 "failed to re-enable regulator when resuming\n");
 592                         return error;
 593                 }
 594
 595                 error = bu21013_init_chip(ts);
 596                 if (error) {
 597                         dev_err(&client->dev,
 598                                 "failed to reinitialize chip when resuming\n");
 599                         return error;
 600                 }
 601         }
 602
 603         ts->touch_stopped = false;
 604         mb();
 605         enable_irq(client->irq);
 606
 607         return 0;
 608 }
 609
 610 static SIMPLE_DEV_PM_OPS(bu21013_dev_pm_ops, bu21013_suspend, bu21013_resume);
 611
 612 static const struct i2c_device_id bu21013_id[] = {
 613         { DRIVER_TP, 0 },
 614         { }
 615 };
 616 MODULE_DEVICE_TABLE(i2c, bu21013_id);
 617
 618 static struct i2c_driver bu21013_driver = {
 619         .driver = {
 620                 .name   =       DRIVER_TP,
 621                 .pm     =       &bu21013_dev_pm_ops,
 622         },
 623         .probe          =       bu21013_probe,
 624         .remove         =       bu21013_remove,
 625         .id_table       =       bu21013_id,
 626 };
 627
 628 module_i2c_driver(bu21013_driver);
 629
 630 MODULE_LICENSE("GPL v2");
 631 MODULE_AUTHOR("Naveen Kumar G <naveen.gaddipati@stericsson.com>");
 632 MODULE_DESCRIPTION("bu21013 touch screen controller driver");