drivers/input/mouse/synaptics_i2c.c

   1 /*
   2  * Synaptics touchpad with I2C interface
   3  *
   4  * Copyright (C) 2009 Compulab, Ltd.
   5  * Mike Rapoport <mike@compulab.co.il>
   6  * Igor Grinberg <grinberg@compulab.co.il>
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file COPYING in the main directory of this archive for
  10  * more details.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/i2c.h>
  15 #include <linux/irq.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/input.h>
  18 #include <linux/delay.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/slab.h>
  21 #include <linux/pm.h>
  22
  23 #define DRIVER_NAME             "synaptics_i2c"
  24 /* maximum product id is 15 characters */
  25 #define PRODUCT_ID_LENGTH       15
  26 #define REGISTER_LENGTH         8
  27
  28 /*
  29  * after soft reset, we should wait for 1 ms
  30  * before the device becomes operational
  31  */
  32 #define SOFT_RESET_DELAY_US     3000
  33 /* and after hard reset, we should wait for max 500ms */
  34 #define HARD_RESET_DELAY_MS     500
  35
  36 /* Registers by SMBus address */
  37 #define PAGE_SEL_REG            0xff
  38 #define DEVICE_STATUS_REG       0x09
  39
  40 /* Registers by RMI address */
  41 #define DEV_CONTROL_REG         0x0000
  42 #define INTERRUPT_EN_REG        0x0001
  43 #define ERR_STAT_REG            0x0002
  44 #define INT_REQ_STAT_REG        0x0003
  45 #define DEV_COMMAND_REG         0x0004
  46
  47 #define RMI_PROT_VER_REG        0x0200
  48 #define MANUFACT_ID_REG         0x0201
  49 #define PHYS_INT_VER_REG        0x0202
  50 #define PROD_PROPERTY_REG       0x0203
  51 #define INFO_QUERY_REG0         0x0204
  52 #define INFO_QUERY_REG1         (INFO_QUERY_REG0 + 1)
  53 #define INFO_QUERY_REG2         (INFO_QUERY_REG0 + 2)
  54 #define INFO_QUERY_REG3         (INFO_QUERY_REG0 + 3)
  55
  56 #define PRODUCT_ID_REG0         0x0210
  57 #define PRODUCT_ID_REG1         (PRODUCT_ID_REG0 + 1)
  58 #define PRODUCT_ID_REG2         (PRODUCT_ID_REG0 + 2)
  59 #define PRODUCT_ID_REG3         (PRODUCT_ID_REG0 + 3)
  60 #define PRODUCT_ID_REG4         (PRODUCT_ID_REG0 + 4)
  61 #define PRODUCT_ID_REG5         (PRODUCT_ID_REG0 + 5)
  62 #define PRODUCT_ID_REG6         (PRODUCT_ID_REG0 + 6)
  63 #define PRODUCT_ID_REG7         (PRODUCT_ID_REG0 + 7)
  64 #define PRODUCT_ID_REG8         (PRODUCT_ID_REG0 + 8)
  65 #define PRODUCT_ID_REG9         (PRODUCT_ID_REG0 + 9)
  66 #define PRODUCT_ID_REG10        (PRODUCT_ID_REG0 + 10)
  67 #define PRODUCT_ID_REG11        (PRODUCT_ID_REG0 + 11)
  68 #define PRODUCT_ID_REG12        (PRODUCT_ID_REG0 + 12)
  69 #define PRODUCT_ID_REG13        (PRODUCT_ID_REG0 + 13)
  70 #define PRODUCT_ID_REG14        (PRODUCT_ID_REG0 + 14)
  71 #define PRODUCT_ID_REG15        (PRODUCT_ID_REG0 + 15)
  72
  73 #define DATA_REG0               0x0400
  74 #define ABS_PRESSURE_REG        0x0401
  75 #define ABS_MSB_X_REG           0x0402
  76 #define ABS_LSB_X_REG           (ABS_MSB_X_REG + 1)
  77 #define ABS_MSB_Y_REG           0x0404
  78 #define ABS_LSB_Y_REG           (ABS_MSB_Y_REG + 1)
  79 #define REL_X_REG               0x0406
  80 #define REL_Y_REG               0x0407
  81
  82 #define DEV_QUERY_REG0          0x1000
  83 #define DEV_QUERY_REG1          (DEV_QUERY_REG0 + 1)
  84 #define DEV_QUERY_REG2          (DEV_QUERY_REG0 + 2)
  85 #define DEV_QUERY_REG3          (DEV_QUERY_REG0 + 3)
  86 #define DEV_QUERY_REG4          (DEV_QUERY_REG0 + 4)
  87 #define DEV_QUERY_REG5          (DEV_QUERY_REG0 + 5)
  88 #define DEV_QUERY_REG6          (DEV_QUERY_REG0 + 6)
  89 #define DEV_QUERY_REG7          (DEV_QUERY_REG0 + 7)
  90 #define DEV_QUERY_REG8          (DEV_QUERY_REG0 + 8)
  91
  92 #define GENERAL_2D_CONTROL_REG  0x1041
  93 #define SENSOR_SENSITIVITY_REG  0x1044
  94 #define SENS_MAX_POS_MSB_REG    0x1046
  95 #define SENS_MAX_POS_LSB_REG    (SENS_MAX_POS_UPPER_REG + 1)
  96
  97 /* Register bits */
  98 /* Device Control Register Bits */
  99 #define REPORT_RATE_1ST_BIT     6
 100
 101 /* Interrupt Enable Register Bits (INTERRUPT_EN_REG) */
 102 #define F10_ABS_INT_ENA         0
 103 #define F10_REL_INT_ENA         1
 104 #define F20_INT_ENA             2
 105
 106 /* Interrupt Request Register Bits (INT_REQ_STAT_REG | DEVICE_STATUS_REG) */
 107 #define F10_ABS_INT_REQ         0
 108 #define F10_REL_INT_REQ         1
 109 #define F20_INT_REQ             2
 110 /* Device Status Register Bits (DEVICE_STATUS_REG) */
 111 #define STAT_CONFIGURED         6
 112 #define STAT_ERROR              7
 113
 114 /* Device Command Register Bits (DEV_COMMAND_REG) */
 115 #define RESET_COMMAND           0x01
 116 #define REZERO_COMMAND          0x02
 117
 118 /* Data Register 0 Bits (DATA_REG0) */
 119 #define GESTURE                 3
 120
 121 /* Device Query Registers Bits */
 122 /* DEV_QUERY_REG3 */
 123 #define HAS_PALM_DETECT         1
 124 #define HAS_MULTI_FING          2
 125 #define HAS_SCROLLER            4
 126 #define HAS_2D_SCROLL           5
 127
 128 /* General 2D Control Register Bits (GENERAL_2D_CONTROL_REG) */
 129 #define NO_DECELERATION         1
 130 #define REDUCE_REPORTING        3
 131 #define NO_FILTER               5
 132
 133 /* Function Masks */
 134 /* Device Control Register Masks (DEV_CONTROL_REG) */
 135 #define REPORT_RATE_MSK         0xc0
 136 #define SLEEP_MODE_MSK          0x07
 137
 138 /* Device Sleep Modes */
 139 #define FULL_AWAKE              0x0
 140 #define NORMAL_OP               0x1
 141 #define LOW_PWR_OP              0x2
 142 #define VERY_LOW_PWR_OP         0x3
 143 #define SENS_SLEEP              0x4
 144 #define SLEEP_MOD               0x5
 145 #define DEEP_SLEEP              0x6
 146 #define HIBERNATE               0x7
 147
 148 /* Interrupt Register Mask */
 149 /* (INT_REQ_STAT_REG | DEVICE_STATUS_REG | INTERRUPT_EN_REG) */
 150 #define INT_ENA_REQ_MSK         0x07
 151 #define INT_ENA_ABS_MSK         0x01
 152 #define INT_ENA_REL_MSK         0x02
 153 #define INT_ENA_F20_MSK         0x04
 154
 155 /* Device Status Register Masks (DEVICE_STATUS_REG) */
 156 #define CONFIGURED_MSK          0x40
 157 #define ERROR_MSK               0x80
 158
 159 /* Data Register 0 Masks */
 160 #define FINGER_WIDTH_MSK        0xf0
 161 #define GESTURE_MSK             0x08
 162 #define SENSOR_STATUS_MSK       0x07
 163
 164 /*
 165  * MSB Position Register Masks
 166  * ABS_MSB_X_REG | ABS_MSB_Y_REG | SENS_MAX_POS_MSB_REG |
 167  * DEV_QUERY_REG3 | DEV_QUERY_REG5
 168  */
 169 #define MSB_POSITION_MSK        0x1f
 170
 171 /* Device Query Registers Masks */
 172
 173 /* DEV_QUERY_REG2 */
 174 #define NUM_EXTRA_POS_MSK       0x07
 175
 176 /* When in IRQ mode read the device every THREAD_IRQ_SLEEP_SECS */
 177 #define THREAD_IRQ_SLEEP_SECS   2
 178 #define THREAD_IRQ_SLEEP_MSECS  (THREAD_IRQ_SLEEP_SECS * MSEC_PER_SEC)
 179
 180 /*
 181  * When in Polling mode and no data received for NO_DATA_THRES msecs
 182  * reduce the polling rate to NO_DATA_SLEEP_MSECS
 183  */
 184 #define NO_DATA_THRES           (MSEC_PER_SEC)
 185 #define NO_DATA_SLEEP_MSECS     (MSEC_PER_SEC / 4)
 186
 187 /* Control touchpad's No Deceleration option */
 188 static bool no_decel = true;
 189 module_param(no_decel, bool, 0644);
 190 MODULE_PARM_DESC(no_decel, "No Deceleration. Default = 1 (on)");
 191
 192 /* Control touchpad's Reduced Reporting option */
 193 static bool reduce_report;
 194 module_param(reduce_report, bool, 0644);
 195 MODULE_PARM_DESC(reduce_report, "Reduced Reporting. Default = 0 (off)");
 196
 197 /* Control touchpad's No Filter option */
 198 static bool no_filter;
 199 module_param(no_filter, bool, 0644);
 200 MODULE_PARM_DESC(no_filter, "No Filter. Default = 0 (off)");
 201
 202 /*
 203  * touchpad Attention line is Active Low and Open Drain,
 204  * therefore should be connected to pulled up line
 205  * and the irq configuration should be set to Falling Edge Trigger
 206  */
 207 /* Control IRQ / Polling option */
 208 static bool polling_req;
 209 module_param(polling_req, bool, 0444);
 210 MODULE_PARM_DESC(polling_req, "Request Polling. Default = 0 (use irq)");
 211
 212 /* Control Polling Rate */
 213 static int scan_rate = 80;
 214 module_param(scan_rate, int, 0644);
 215 MODULE_PARM_DESC(scan_rate, "Polling rate in times/sec. Default = 80");
 216
 217 /* The main device structure */
 218 struct synaptics_i2c {
 219         struct i2c_client       *client;
 220         struct input_dev        *input;
 221         struct delayed_work     dwork;
 222         int                     no_data_count;
 223         int                     no_decel_param;
 224         int                     reduce_report_param;
 225         int                     no_filter_param;
 226         int                     scan_rate_param;
 227         int                     scan_ms;
 228 };
 229
 230 static inline void set_scan_rate(struct synaptics_i2c *touch, int scan_rate)
 231 {
 232         touch->scan_ms = MSEC_PER_SEC / scan_rate;
 233         touch->scan_rate_param = scan_rate;
 234 }
 235
 236 /*
 237  * Driver's initial design makes no race condition possible on i2c bus,
 238  * so there is no need in any locking.
 239  * Keep it in mind, while playing with the code.
 240  */
 241 static s32 synaptics_i2c_reg_get(struct i2c_client *client, u16 reg)
 242 {
 243         int ret;
 244
 245         ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
 246         if (ret == 0)
 247                 ret = i2c_smbus_read_byte_data(client, reg & 0xff);
 248
 249         return ret;
 250 }
 251
 252 static s32 synaptics_i2c_reg_set(struct i2c_client *client, u16 reg, u8 val)
 253 {
 254         int ret;
 255
 256         ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
 257         if (ret == 0)
 258                 ret = i2c_smbus_write_byte_data(client, reg & 0xff, val);
 259
 260         return ret;
 261 }
 262
 263 static s32 synaptics_i2c_word_get(struct i2c_client *client, u16 reg)
 264 {
 265         int ret;
 266
 267         ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
 268         if (ret == 0)
 269                 ret = i2c_smbus_read_word_data(client, reg & 0xff);
 270
 271         return ret;
 272 }
 273
 274 static int synaptics_i2c_config(struct i2c_client *client)
 275 {
 276         int ret, control;
 277         u8 int_en;
 278
 279         /* set Report Rate to Device Highest (>=80) and Sleep to normal */
 280         ret = synaptics_i2c_reg_set(client, DEV_CONTROL_REG, 0xc1);
 281         if (ret)
 282                 return ret;
 283
 284         /* set Interrupt Disable to Func20 / Enable to Func10) */
 285         int_en = (polling_req) ? 0 : INT_ENA_ABS_MSK | INT_ENA_REL_MSK;
 286         ret = synaptics_i2c_reg_set(client, INTERRUPT_EN_REG, int_en);
 287         if (ret)
 288                 return ret;
 289
 290         control = synaptics_i2c_reg_get(client, GENERAL_2D_CONTROL_REG);
 291         /* No Deceleration */
 292         control |= no_decel ? 1 << NO_DECELERATION : 0;
 293         /* Reduced Reporting */
 294         control |= reduce_report ? 1 << REDUCE_REPORTING : 0;
 295         /* No Filter */
 296         control |= no_filter ? 1 << NO_FILTER : 0;
 297         ret = synaptics_i2c_reg_set(client, GENERAL_2D_CONTROL_REG, control);
 298         if (ret)
 299                 return ret;
 300
 301         return 0;
 302 }
 303
 304 static int synaptics_i2c_reset_config(struct i2c_client *client)
 305 {
 306         int ret;
 307
 308         /* Reset the Touchpad */
 309         ret = synaptics_i2c_reg_set(client, DEV_COMMAND_REG, RESET_COMMAND);
 310         if (ret) {
 311                 dev_err(&client->dev, "Unable to reset device\n");
 312         } else {
 313                 usleep_range(SOFT_RESET_DELAY_US, SOFT_RESET_DELAY_US + 100);
 314                 ret = synaptics_i2c_config(client);
 315                 if (ret)
 316                         dev_err(&client->dev, "Unable to config device\n");
 317         }
 318
 319         return ret;
 320 }
 321
 322 static int synaptics_i2c_check_error(struct i2c_client *client)
 323 {
 324         int status, ret = 0;
 325
 326         status = i2c_smbus_read_byte_data(client, DEVICE_STATUS_REG) &
 327                 (CONFIGURED_MSK | ERROR_MSK);
 328
 329         if (status != CONFIGURED_MSK)
 330                 ret = synaptics_i2c_reset_config(client);
 331
 332         return ret;
 333 }
 334
 335 static bool synaptics_i2c_get_input(struct synaptics_i2c *touch)
 336 {
 337         struct input_dev *input = touch->input;
 338         int xy_delta, gesture;
 339         s32 data;
 340         s8 x_delta, y_delta;
 341
 342         /* Deal with spontaneous resets and errors */
 343         if (synaptics_i2c_check_error(touch->client))
 344                 return false;
 345
 346         /* Get Gesture Bit */
 347         data = synaptics_i2c_reg_get(touch->client, DATA_REG0);
 348         gesture = (data >> GESTURE) & 0x1;
 349
 350         /*
 351          * Get Relative axes. we have to get them in one shot,
 352          * so we get 2 bytes starting from REL_X_REG.
 353          */
 354         xy_delta = synaptics_i2c_word_get(touch->client, REL_X_REG) & 0xffff;
 355
 356         /* Separate X from Y */
 357         x_delta = xy_delta & 0xff;
 358         y_delta = (xy_delta >> REGISTER_LENGTH) & 0xff;
 359
 360         /* Report the button event */
 361         input_report_key(input, BTN_LEFT, gesture);
 362
 363         /* Report the deltas */
 364         input_report_rel(input, REL_X, x_delta);
 365         input_report_rel(input, REL_Y, -y_delta);
 366         input_sync(input);
 367
 368         return xy_delta || gesture;
 369 }
 370
 371 static irqreturn_t synaptics_i2c_irq(int irq, void *dev_id)
 372 {
 373         struct synaptics_i2c *touch = dev_id;
 374
 375         mod_delayed_work(system_wq, &touch->dwork, 0);
 376
 377         return IRQ_HANDLED;
 378 }
 379
 380 static void synaptics_i2c_check_params(struct synaptics_i2c *touch)
 381 {
 382         bool reset = false;
 383
 384         if (scan_rate != touch->scan_rate_param)
 385                 set_scan_rate(touch, scan_rate);
 386
 387         if (no_decel != touch->no_decel_param) {
 388                 touch->no_decel_param = no_decel;
 389                 reset = true;
 390         }
 391
 392         if (no_filter != touch->no_filter_param) {
 393                 touch->no_filter_param = no_filter;
 394                 reset = true;
 395         }
 396
 397         if (reduce_report != touch->reduce_report_param) {
 398                 touch->reduce_report_param = reduce_report;
 399                 reset = true;
 400         }
 401
 402         if (reset)
 403                 synaptics_i2c_reset_config(touch->client);
 404 }
 405
 406 /* Control the Device polling rate / Work Handler sleep time */
 407 static unsigned long synaptics_i2c_adjust_delay(struct synaptics_i2c *touch,
 408                                                 bool have_data)
 409 {
 410         unsigned long delay, nodata_count_thres;
 411
 412         if (polling_req) {
 413                 delay = touch->scan_ms;
 414                 if (have_data) {
 415                         touch->no_data_count = 0;
 416                 } else {
 417                         nodata_count_thres = NO_DATA_THRES / touch->scan_ms;
 418                         if (touch->no_data_count < nodata_count_thres)
 419                                 touch->no_data_count++;
 420                         else
 421                                 delay = NO_DATA_SLEEP_MSECS;
 422                 }
 423                 return msecs_to_jiffies(delay);
 424         } else {
 425                 delay = msecs_to_jiffies(THREAD_IRQ_SLEEP_MSECS);
 426                 return round_jiffies_relative(delay);
 427         }
 428 }
 429
 430 /* Work Handler */
 431 static void synaptics_i2c_work_handler(struct work_struct *work)
 432 {
 433         bool have_data;
 434         struct synaptics_i2c *touch =
 435                         container_of(work, struct synaptics_i2c, dwork.work);
 436         unsigned long delay;
 437
 438         synaptics_i2c_check_params(touch);
 439
 440         have_data = synaptics_i2c_get_input(touch);
 441         delay = synaptics_i2c_adjust_delay(touch, have_data);
 442
 443         /*
 444          * While interrupt driven, there is no real need to poll the device.
 445          * But touchpads are very sensitive, so there could be errors
 446          * related to physical environment and the attention line isn't
 447          * necessarily asserted. In such case we can lose the touchpad.
 448          * We poll the device once in THREAD_IRQ_SLEEP_SECS and
 449          * if error is detected, we try to reset and reconfigure the touchpad.
 450          */
 451         mod_delayed_work(system_wq, &touch->dwork, delay);
 452 }
 453
 454 static int synaptics_i2c_open(struct input_dev *input)
 455 {
 456         struct synaptics_i2c *touch = input_get_drvdata(input);
 457         int ret;
 458
 459         ret = synaptics_i2c_reset_config(touch->client);
 460         if (ret)
 461                 return ret;
 462
 463         if (polling_req)
 464                 mod_delayed_work(system_wq, &touch->dwork,
 465                                 msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
 466
 467         return 0;
 468 }
 469
 470 static void synaptics_i2c_close(struct input_dev *input)
 471 {
 472         struct synaptics_i2c *touch = input_get_drvdata(input);
 473
 474         if (!polling_req)
 475                 synaptics_i2c_reg_set(touch->client, INTERRUPT_EN_REG, 0);
 476
 477         cancel_delayed_work_sync(&touch->dwork);
 478
 479         /* Save some power */
 480         synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP);
 481 }
 482
 483 static void synaptics_i2c_set_input_params(struct synaptics_i2c *touch)
 484 {
 485         struct input_dev *input = touch->input;
 486
 487         input->name = touch->client->name;
 488         input->phys = touch->client->adapter->name;
 489         input->id.bustype = BUS_I2C;
 490         input->id.version = synaptics_i2c_word_get(touch->client,
 491                                                    INFO_QUERY_REG0);
 492         input->dev.parent = &touch->client->dev;
 493         input->open = synaptics_i2c_open;
 494         input->close = synaptics_i2c_close;
 495         input_set_drvdata(input, touch);
 496
 497         /* Register the device as mouse */
 498         __set_bit(EV_REL, input->evbit);
 499         __set_bit(REL_X, input->relbit);
 500         __set_bit(REL_Y, input->relbit);
 501
 502         /* Register device's buttons and keys */
 503         __set_bit(EV_KEY, input->evbit);
 504         __set_bit(BTN_LEFT, input->keybit);
 505 }
 506
 507 static struct synaptics_i2c *synaptics_i2c_touch_create(struct i2c_client *client)
 508 {
 509         struct synaptics_i2c *touch;
 510
 511         touch = kzalloc(sizeof(struct synaptics_i2c), GFP_KERNEL);
 512         if (!touch)
 513                 return NULL;
 514
 515         touch->client = client;
 516         touch->no_decel_param = no_decel;
 517         touch->scan_rate_param = scan_rate;
 518         set_scan_rate(touch, scan_rate);
 519         INIT_DELAYED_WORK(&touch->dwork, synaptics_i2c_work_handler);
 520
 521         return touch;
 522 }
 523
 524 static int synaptics_i2c_probe(struct i2c_client *client,
 525                                const struct i2c_device_id *dev_id)
 526 {
 527         int ret;
 528         struct synaptics_i2c *touch;
 529
 530         touch = synaptics_i2c_touch_create(client);
 531         if (!touch)
 532                 return -ENOMEM;
 533
 534         ret = synaptics_i2c_reset_config(client);
 535         if (ret)
 536                 goto err_mem_free;
 537
 538         if (client->irq < 1)
 539                 polling_req = true;
 540
 541         touch->input = input_allocate_device();
 542         if (!touch->input) {
 543                 ret = -ENOMEM;
 544                 goto err_mem_free;
 545         }
 546
 547         synaptics_i2c_set_input_params(touch);
 548
 549         if (!polling_req) {
 550                 dev_dbg(&touch->client->dev,
 551                          "Requesting IRQ: %d\n", touch->client->irq);
 552
 553                 ret = request_irq(touch->client->irq, synaptics_i2c_irq,
 554                                   IRQ_TYPE_EDGE_FALLING,
 555                                   DRIVER_NAME, touch);
 556                 if (ret) {
 557                         dev_warn(&touch->client->dev,
 558                                   "IRQ request failed: %d, "
 559                                   "falling back to polling\n", ret);
 560                         polling_req = true;
 561                         synaptics_i2c_reg_set(touch->client,
 562                                               INTERRUPT_EN_REG, 0);
 563                 }
 564         }
 565
 566         if (polling_req)
 567                 dev_dbg(&touch->client->dev,
 568                          "Using polling at rate: %d times/sec\n", scan_rate);
 569
 570         /* Register the device in input subsystem */
 571         ret = input_register_device(touch->input);
 572         if (ret) {
 573                 dev_err(&client->dev,
 574                          "Input device register failed: %d\n", ret);
 575                 goto err_input_free;
 576         }
 577
 578         i2c_set_clientdata(client, touch);
 579
 580         return 0;
 581
 582 err_input_free:
 583         input_free_device(touch->input);
 584 err_mem_free:
 585         kfree(touch);
 586
 587         return ret;
 588 }
 589
 590 static int synaptics_i2c_remove(struct i2c_client *client)
 591 {
 592         struct synaptics_i2c *touch = i2c_get_clientdata(client);
 593
 594         if (!polling_req)
 595                 free_irq(client->irq, touch);
 596
 597         input_unregister_device(touch->input);
 598         kfree(touch);
 599
 600         return 0;
 601 }
 602
 603 static int __maybe_unused synaptics_i2c_suspend(struct device *dev)
 604 {
 605         struct i2c_client *client = to_i2c_client(dev);
 606         struct synaptics_i2c *touch = i2c_get_clientdata(client);
 607
 608         cancel_delayed_work_sync(&touch->dwork);
 609
 610         /* Save some power */
 611         synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP);
 612
 613         return 0;
 614 }
 615
 616 static int __maybe_unused synaptics_i2c_resume(struct device *dev)
 617 {
 618         int ret;
 619         struct i2c_client *client = to_i2c_client(dev);
 620         struct synaptics_i2c *touch = i2c_get_clientdata(client);
 621
 622         ret = synaptics_i2c_reset_config(client);
 623         if (ret)
 624                 return ret;
 625
 626         mod_delayed_work(system_wq, &touch->dwork,
 627                                 msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
 628
 629         return 0;
 630 }
 631
 632 static SIMPLE_DEV_PM_OPS(synaptics_i2c_pm, synaptics_i2c_suspend,
 633                          synaptics_i2c_resume);
 634
 635 static const struct i2c_device_id synaptics_i2c_id_table[] = {
 636         { "synaptics_i2c", 0 },
 637         { },
 638 };
 639 MODULE_DEVICE_TABLE(i2c, synaptics_i2c_id_table);
 640
 641 #ifdef CONFIG_OF
 642 static const struct of_device_id synaptics_i2c_of_match[] = {
 643         { .compatible = "synaptics,synaptics_i2c", },
 644         { },
 645 };
 646 MODULE_DEVICE_TABLE(of, synaptics_i2c_of_match);
 647 #endif
 648
 649 static struct i2c_driver synaptics_i2c_driver = {
 650         .driver = {
 651                 .name   = DRIVER_NAME,
 652                 .of_match_table = of_match_ptr(synaptics_i2c_of_match),
 653                 .pm     = &synaptics_i2c_pm,
 654         },
 655
 656         .probe          = synaptics_i2c_probe,
 657         .remove         = synaptics_i2c_remove,
 658
 659         .id_table       = synaptics_i2c_id_table,
 660 };
 661
 662 module_i2c_driver(synaptics_i2c_driver);
 663
 664 MODULE_DESCRIPTION("Synaptics I2C touchpad driver");
 665 MODULE_AUTHOR("Mike Rapoport, Igor Grinberg, Compulab");
 666 MODULE_LICENSE("GPL");
 667