drivers/input/misc/ad714x.c

   1 /*
   2  * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A
   3  *
   4  * Copyright 2009-2011 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2 or later.
   7  */
   8
   9 #include <linux/device.h>
  10 #include <linux/input.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/slab.h>
  13 #include <linux/input/ad714x.h>
  14 #include <linux/module.h>
  15 #include "ad714x.h"
  16
  17 #define AD714X_PWR_CTRL           0x0
  18 #define AD714X_STG_CAL_EN_REG     0x1
  19 #define AD714X_AMB_COMP_CTRL0_REG 0x2
  20 #define AD714X_PARTID_REG         0x17
  21 #define AD7142_PARTID             0xE620
  22 #define AD7143_PARTID             0xE630
  23 #define AD7147_PARTID             0x1470
  24 #define AD7148_PARTID             0x1480
  25 #define AD714X_STAGECFG_REG       0x80
  26 #define AD714X_SYSCFG_REG         0x0
  27
  28 #define STG_LOW_INT_EN_REG     0x5
  29 #define STG_HIGH_INT_EN_REG    0x6
  30 #define STG_COM_INT_EN_REG     0x7
  31 #define STG_LOW_INT_STA_REG    0x8
  32 #define STG_HIGH_INT_STA_REG   0x9
  33 #define STG_COM_INT_STA_REG    0xA
  34
  35 #define CDC_RESULT_S0          0xB
  36 #define CDC_RESULT_S1          0xC
  37 #define CDC_RESULT_S2          0xD
  38 #define CDC_RESULT_S3          0xE
  39 #define CDC_RESULT_S4          0xF
  40 #define CDC_RESULT_S5          0x10
  41 #define CDC_RESULT_S6          0x11
  42 #define CDC_RESULT_S7          0x12
  43 #define CDC_RESULT_S8          0x13
  44 #define CDC_RESULT_S9          0x14
  45 #define CDC_RESULT_S10         0x15
  46 #define CDC_RESULT_S11         0x16
  47
  48 #define STAGE0_AMBIENT          0xF1
  49 #define STAGE1_AMBIENT          0x115
  50 #define STAGE2_AMBIENT          0x139
  51 #define STAGE3_AMBIENT          0x15D
  52 #define STAGE4_AMBIENT          0x181
  53 #define STAGE5_AMBIENT          0x1A5
  54 #define STAGE6_AMBIENT          0x1C9
  55 #define STAGE7_AMBIENT          0x1ED
  56 #define STAGE8_AMBIENT          0x211
  57 #define STAGE9_AMBIENT          0x234
  58 #define STAGE10_AMBIENT         0x259
  59 #define STAGE11_AMBIENT         0x27D
  60
  61 #define PER_STAGE_REG_NUM      36
  62 #define STAGE_CFGREG_NUM       8
  63 #define SYS_CFGREG_NUM         8
  64
  65 /*
  66  * driver information which will be used to maintain the software flow
  67  */
  68 enum ad714x_device_state { IDLE, JITTER, ACTIVE, SPACE };
  69
  70 struct ad714x_slider_drv {
  71         int highest_stage;
  72         int abs_pos;
  73         int flt_pos;
  74         enum ad714x_device_state state;
  75         struct input_dev *input;
  76 };
  77
  78 struct ad714x_wheel_drv {
  79         int abs_pos;
  80         int flt_pos;
  81         int pre_highest_stage;
  82         int highest_stage;
  83         enum ad714x_device_state state;
  84         struct input_dev *input;
  85 };
  86
  87 struct ad714x_touchpad_drv {
  88         int x_highest_stage;
  89         int x_flt_pos;
  90         int x_abs_pos;
  91         int y_highest_stage;
  92         int y_flt_pos;
  93         int y_abs_pos;
  94         int left_ep;
  95         int left_ep_val;
  96         int right_ep;
  97         int right_ep_val;
  98         int top_ep;
  99         int top_ep_val;
 100         int bottom_ep;
 101         int bottom_ep_val;
 102         enum ad714x_device_state state;
 103         struct input_dev *input;
 104 };
 105
 106 struct ad714x_button_drv {
 107         enum ad714x_device_state state;
 108         /*
 109          * Unlike slider/wheel/touchpad, all buttons point to
 110          * same input_dev instance
 111          */
 112         struct input_dev *input;
 113 };
 114
 115 struct ad714x_driver_data {
 116         struct ad714x_slider_drv *slider;
 117         struct ad714x_wheel_drv *wheel;
 118         struct ad714x_touchpad_drv *touchpad;
 119         struct ad714x_button_drv *button;
 120 };
 121
 122 /*
 123  * information to integrate all things which will be private data
 124  * of spi/i2c device
 125  */
 126
 127 static void ad714x_use_com_int(struct ad714x_chip *ad714x,
 128                                 int start_stage, int end_stage)
 129 {
 130         unsigned short data;
 131         unsigned short mask;
 132
 133         mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 134
 135         ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
 136         data |= 1 << end_stage;
 137         ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 138
 139         ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
 140         data &= ~mask;
 141         ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 142 }
 143
 144 static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
 145                                 int start_stage, int end_stage)
 146 {
 147         unsigned short data;
 148         unsigned short mask;
 149
 150         mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 151
 152         ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
 153         data &= ~(1 << end_stage);
 154         ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 155
 156         ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
 157         data |= mask;
 158         ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 159 }
 160
 161 static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
 162                                         int start_stage, int end_stage)
 163 {
 164         int max_res = 0;
 165         int max_idx = 0;
 166         int i;
 167
 168         for (i = start_stage; i <= end_stage; i++) {
 169                 if (ad714x->sensor_val[i] > max_res) {
 170                         max_res = ad714x->sensor_val[i];
 171                         max_idx = i;
 172                 }
 173         }
 174
 175         return max_idx;
 176 }
 177
 178 static int ad714x_cal_abs_pos(struct ad714x_chip *ad714x,
 179                                 int start_stage, int end_stage,
 180                                 int highest_stage, int max_coord)
 181 {
 182         int a_param, b_param;
 183
 184         if (highest_stage == start_stage) {
 185                 a_param = ad714x->sensor_val[start_stage + 1];
 186                 b_param = ad714x->sensor_val[start_stage] +
 187                         ad714x->sensor_val[start_stage + 1];
 188         } else if (highest_stage == end_stage) {
 189                 a_param = ad714x->sensor_val[end_stage] *
 190                         (end_stage - start_stage) +
 191                         ad714x->sensor_val[end_stage - 1] *
 192                         (end_stage - start_stage - 1);
 193                 b_param = ad714x->sensor_val[end_stage] +
 194                         ad714x->sensor_val[end_stage - 1];
 195         } else {
 196                 a_param = ad714x->sensor_val[highest_stage] *
 197                         (highest_stage - start_stage) +
 198                         ad714x->sensor_val[highest_stage - 1] *
 199                         (highest_stage - start_stage - 1) +
 200                         ad714x->sensor_val[highest_stage + 1] *
 201                         (highest_stage - start_stage + 1);
 202                 b_param = ad714x->sensor_val[highest_stage] +
 203                         ad714x->sensor_val[highest_stage - 1] +
 204                         ad714x->sensor_val[highest_stage + 1];
 205         }
 206
 207         return (max_coord / (end_stage - start_stage)) * a_param / b_param;
 208 }
 209
 210 /*
 211  * One button can connect to multi positive and negative of CDCs
 212  * Multi-buttons can connect to same positive/negative of one CDC
 213  */
 214 static void ad714x_button_state_machine(struct ad714x_chip *ad714x, int idx)
 215 {
 216         struct ad714x_button_plat *hw = &ad714x->hw->button[idx];
 217         struct ad714x_button_drv *sw = &ad714x->sw->button[idx];
 218
 219         switch (sw->state) {
 220         case IDLE:
 221                 if (((ad714x->h_state & hw->h_mask) == hw->h_mask) &&
 222                     ((ad714x->l_state & hw->l_mask) == hw->l_mask)) {
 223                         dev_dbg(ad714x->dev, "button %d touched\n", idx);
 224                         input_report_key(sw->input, hw->keycode, 1);
 225                         input_sync(sw->input);
 226                         sw->state = ACTIVE;
 227                 }
 228                 break;
 229
 230         case ACTIVE:
 231                 if (((ad714x->h_state & hw->h_mask) != hw->h_mask) ||
 232                     ((ad714x->l_state & hw->l_mask) != hw->l_mask)) {
 233                         dev_dbg(ad714x->dev, "button %d released\n", idx);
 234                         input_report_key(sw->input, hw->keycode, 0);
 235                         input_sync(sw->input);
 236                         sw->state = IDLE;
 237                 }
 238                 break;
 239
 240         default:
 241                 break;
 242         }
 243 }
 244
 245 /*
 246  * The response of a sensor is defined by the absolute number of codes
 247  * between the current CDC value and the ambient value.
 248  */
 249 static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 250 {
 251         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 252         int i;
 253
 254         ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
 255                         &ad714x->adc_reg[hw->start_stage],
 256                         hw->end_stage - hw->start_stage + 1);
 257
 258         for (i = hw->start_stage; i <= hw->end_stage; i++) {
 259                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 260                                 &ad714x->amb_reg[i], 1);
 261
 262                 ad714x->sensor_val[i] =
 263                         abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]);
 264         }
 265 }
 266
 267 static void ad714x_slider_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
 268 {
 269         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 270         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 271
 272         sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
 273                         hw->end_stage);
 274
 275         dev_dbg(ad714x->dev, "slider %d highest_stage:%d\n", idx,
 276                 sw->highest_stage);
 277 }
 278
 279 /*
 280  * The formulae are very straight forward. It uses the sensor with the
 281  * highest response and the 2 adjacent ones.
 282  * When Sensor 0 has the highest response, only sensor 0 and sensor 1
 283  * are used in the calculations. Similarly when the last sensor has the
 284  * highest response, only the last sensor and the second last sensors
 285  * are used in the calculations.
 286  *
 287  * For i= idx_of_peak_Sensor-1 to i= idx_of_peak_Sensor+1
 288  *         v += Sensor response(i)*i
 289  *         w += Sensor response(i)
 290  * POS=(Number_of_Positions_Wanted/(Number_of_Sensors_Used-1)) *(v/w)
 291  */
 292 static void ad714x_slider_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
 293 {
 294         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 295         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 296
 297         sw->abs_pos = ad714x_cal_abs_pos(ad714x, hw->start_stage, hw->end_stage,
 298                 sw->highest_stage, hw->max_coord);
 299
 300         dev_dbg(ad714x->dev, "slider %d absolute position:%d\n", idx,
 301                 sw->abs_pos);
 302 }
 303
 304 /*
 305  * To minimise the Impact of the noise on the algorithm, ADI developed a
 306  * routine that filters the CDC results after they have been read by the
 307  * host processor.
 308  * The filter used is an Infinite Input Response(IIR) filter implemented
 309  * in firmware and attenuates the noise on the CDC results after they've
 310  * been read by the host processor.
 311  * Filtered_CDC_result = (Filtered_CDC_result * (10 - Coefficient) +
 312  *                              Latest_CDC_result * Coefficient)/10
 313  */
 314 static void ad714x_slider_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
 315 {
 316         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 317
 318         sw->flt_pos = (sw->flt_pos * (10 - 4) +
 319                         sw->abs_pos * 4)/10;
 320
 321         dev_dbg(ad714x->dev, "slider %d filter position:%d\n", idx,
 322                 sw->flt_pos);
 323 }
 324
 325 static void ad714x_slider_use_com_int(struct ad714x_chip *ad714x, int idx)
 326 {
 327         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 328
 329         ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
 330 }
 331
 332 static void ad714x_slider_use_thr_int(struct ad714x_chip *ad714x, int idx)
 333 {
 334         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 335
 336         ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
 337 }
 338
 339 static void ad714x_slider_state_machine(struct ad714x_chip *ad714x, int idx)
 340 {
 341         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 342         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 343         unsigned short h_state, c_state;
 344         unsigned short mask;
 345
 346         mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
 347
 348         h_state = ad714x->h_state & mask;
 349         c_state = ad714x->c_state & mask;
 350
 351         switch (sw->state) {
 352         case IDLE:
 353                 if (h_state) {
 354                         sw->state = JITTER;
 355                         /* In End of Conversion interrupt mode, the AD714X
 356                          * continuously generates hardware interrupts.
 357                          */
 358                         ad714x_slider_use_com_int(ad714x, idx);
 359                         dev_dbg(ad714x->dev, "slider %d touched\n", idx);
 360                 }
 361                 break;
 362
 363         case JITTER:
 364                 if (c_state == mask) {
 365                         ad714x_slider_cal_sensor_val(ad714x, idx);
 366                         ad714x_slider_cal_highest_stage(ad714x, idx);
 367                         ad714x_slider_cal_abs_pos(ad714x, idx);
 368                         sw->flt_pos = sw->abs_pos;
 369                         sw->state = ACTIVE;
 370                 }
 371                 break;
 372
 373         case ACTIVE:
 374                 if (c_state == mask) {
 375                         if (h_state) {
 376                                 ad714x_slider_cal_sensor_val(ad714x, idx);
 377                                 ad714x_slider_cal_highest_stage(ad714x, idx);
 378                                 ad714x_slider_cal_abs_pos(ad714x, idx);
 379                                 ad714x_slider_cal_flt_pos(ad714x, idx);
 380                                 input_report_abs(sw->input, ABS_X, sw->flt_pos);
 381                                 input_report_key(sw->input, BTN_TOUCH, 1);
 382                         } else {
 383                                 /* When the user lifts off the sensor, configure
 384                                  * the AD714X back to threshold interrupt mode.
 385                                  */
 386                                 ad714x_slider_use_thr_int(ad714x, idx);
 387                                 sw->state = IDLE;
 388                                 input_report_key(sw->input, BTN_TOUCH, 0);
 389                                 dev_dbg(ad714x->dev, "slider %d released\n",
 390                                         idx);
 391                         }
 392                         input_sync(sw->input);
 393                 }
 394                 break;
 395
 396         default:
 397                 break;
 398         }
 399 }
 400
 401 /*
 402  * When the scroll wheel is activated, we compute the absolute position based
 403  * on the sensor values. To calculate the position, we first determine the
 404  * sensor that has the greatest response among the 8 sensors that constitutes
 405  * the scrollwheel. Then we determined the 2 sensors on either sides of the
 406  * sensor with the highest response and we apply weights to these sensors.
 407  */
 408 static void ad714x_wheel_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
 409 {
 410         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 411         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 412
 413         sw->pre_highest_stage = sw->highest_stage;
 414         sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
 415                         hw->end_stage);
 416
 417         dev_dbg(ad714x->dev, "wheel %d highest_stage:%d\n", idx,
 418                 sw->highest_stage);
 419 }
 420
 421 static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 422 {
 423         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 424         int i;
 425
 426         ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
 427                         &ad714x->adc_reg[hw->start_stage],
 428                         hw->end_stage - hw->start_stage + 1);
 429
 430         for (i = hw->start_stage; i <= hw->end_stage; i++) {
 431                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 432                                 &ad714x->amb_reg[i], 1);
 433                 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
 434                         ad714x->sensor_val[i] =
 435                                 ad714x->adc_reg[i] - ad714x->amb_reg[i];
 436                 else
 437                         ad714x->sensor_val[i] = 0;
 438         }
 439 }
 440
 441 /*
 442  * When the scroll wheel is activated, we compute the absolute position based
 443  * on the sensor values. To calculate the position, we first determine the
 444  * sensor that has the greatest response among the sensors that constitutes
 445  * the scrollwheel. Then we determined the sensors on either sides of the
 446  * sensor with the highest response and we apply weights to these sensors. The
 447  * result of this computation gives us the mean value.
 448  */
 449
 450 static void ad714x_wheel_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
 451 {
 452         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 453         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 454         int stage_num = hw->end_stage - hw->start_stage + 1;
 455         int first_before, highest, first_after;
 456         int a_param, b_param;
 457
 458         first_before = (sw->highest_stage + stage_num - 1) % stage_num;
 459         highest = sw->highest_stage;
 460         first_after = (sw->highest_stage + stage_num + 1) % stage_num;
 461
 462         a_param = ad714x->sensor_val[highest] *
 463                 (highest - hw->start_stage) +
 464                 ad714x->sensor_val[first_before] *
 465                 (highest - hw->start_stage - 1) +
 466                 ad714x->sensor_val[first_after] *
 467                 (highest - hw->start_stage + 1);
 468         b_param = ad714x->sensor_val[highest] +
 469                 ad714x->sensor_val[first_before] +
 470                 ad714x->sensor_val[first_after];
 471
 472         sw->abs_pos = ((hw->max_coord / (hw->end_stage - hw->start_stage)) *
 473                         a_param) / b_param;
 474
 475         if (sw->abs_pos > hw->max_coord)
 476                 sw->abs_pos = hw->max_coord;
 477         else if (sw->abs_pos < 0)
 478                 sw->abs_pos = 0;
 479 }
 480
 481 static void ad714x_wheel_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
 482 {
 483         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 484         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 485         if (((sw->pre_highest_stage == hw->end_stage) &&
 486                         (sw->highest_stage == hw->start_stage)) ||
 487             ((sw->pre_highest_stage == hw->start_stage) &&
 488                         (sw->highest_stage == hw->end_stage)))
 489                 sw->flt_pos = sw->abs_pos;
 490         else
 491                 sw->flt_pos = ((sw->flt_pos * 30) + (sw->abs_pos * 71)) / 100;
 492
 493         if (sw->flt_pos > hw->max_coord)
 494                 sw->flt_pos = hw->max_coord;
 495 }
 496
 497 static void ad714x_wheel_use_com_int(struct ad714x_chip *ad714x, int idx)
 498 {
 499         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 500
 501         ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
 502 }
 503
 504 static void ad714x_wheel_use_thr_int(struct ad714x_chip *ad714x, int idx)
 505 {
 506         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 507
 508         ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
 509 }
 510
 511 static void ad714x_wheel_state_machine(struct ad714x_chip *ad714x, int idx)
 512 {
 513         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 514         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 515         unsigned short h_state, c_state;
 516         unsigned short mask;
 517
 518         mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
 519
 520         h_state = ad714x->h_state & mask;
 521         c_state = ad714x->c_state & mask;
 522
 523         switch (sw->state) {
 524         case IDLE:
 525                 if (h_state) {
 526                         sw->state = JITTER;
 527                         /* In End of Conversion interrupt mode, the AD714X
 528                          * continuously generates hardware interrupts.
 529                          */
 530                         ad714x_wheel_use_com_int(ad714x, idx);
 531                         dev_dbg(ad714x->dev, "wheel %d touched\n", idx);
 532                 }
 533                 break;
 534
 535         case JITTER:
 536                 if (c_state == mask)    {
 537                         ad714x_wheel_cal_sensor_val(ad714x, idx);
 538                         ad714x_wheel_cal_highest_stage(ad714x, idx);
 539                         ad714x_wheel_cal_abs_pos(ad714x, idx);
 540                         sw->flt_pos = sw->abs_pos;
 541                         sw->state = ACTIVE;
 542                 }
 543                 break;
 544
 545         case ACTIVE:
 546                 if (c_state == mask) {
 547                         if (h_state) {
 548                                 ad714x_wheel_cal_sensor_val(ad714x, idx);
 549                                 ad714x_wheel_cal_highest_stage(ad714x, idx);
 550                                 ad714x_wheel_cal_abs_pos(ad714x, idx);
 551                                 ad714x_wheel_cal_flt_pos(ad714x, idx);
 552                                 input_report_abs(sw->input, ABS_WHEEL,
 553                                         sw->flt_pos);
 554                                 input_report_key(sw->input, BTN_TOUCH, 1);
 555                         } else {
 556                                 /* When the user lifts off the sensor, configure
 557                                  * the AD714X back to threshold interrupt mode.
 558                                  */
 559                                 ad714x_wheel_use_thr_int(ad714x, idx);
 560                                 sw->state = IDLE;
 561                                 input_report_key(sw->input, BTN_TOUCH, 0);
 562
 563                                 dev_dbg(ad714x->dev, "wheel %d released\n",
 564                                         idx);
 565                         }
 566                         input_sync(sw->input);
 567                 }
 568                 break;
 569
 570         default:
 571                 break;
 572         }
 573 }
 574
 575 static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 576 {
 577         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 578         int i;
 579
 580         ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage,
 581                         &ad714x->adc_reg[hw->x_start_stage],
 582                         hw->x_end_stage - hw->x_start_stage + 1);
 583
 584         for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
 585                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 586                                 &ad714x->amb_reg[i], 1);
 587                 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
 588                         ad714x->sensor_val[i] =
 589                                 ad714x->adc_reg[i] - ad714x->amb_reg[i];
 590                 else
 591                         ad714x->sensor_val[i] = 0;
 592         }
 593 }
 594
 595 static void touchpad_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
 596 {
 597         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 598         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 599
 600         sw->x_highest_stage = ad714x_cal_highest_stage(ad714x,
 601                 hw->x_start_stage, hw->x_end_stage);
 602         sw->y_highest_stage = ad714x_cal_highest_stage(ad714x,
 603                 hw->y_start_stage, hw->y_end_stage);
 604
 605         dev_dbg(ad714x->dev,
 606                 "touchpad %d x_highest_stage:%d, y_highest_stage:%d\n",
 607                 idx, sw->x_highest_stage, sw->y_highest_stage);
 608 }
 609
 610 /*
 611  * If 2 fingers are touching the sensor then 2 peaks can be observed in the
 612  * distribution.
 613  * The arithmetic doesn't support to get absolute coordinates for multi-touch
 614  * yet.
 615  */
 616 static int touchpad_check_second_peak(struct ad714x_chip *ad714x, int idx)
 617 {
 618         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 619         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 620         int i;
 621
 622         for (i = hw->x_start_stage; i < sw->x_highest_stage; i++) {
 623                 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
 624                         > (ad714x->sensor_val[i + 1] / 10))
 625                         return 1;
 626         }
 627
 628         for (i = sw->x_highest_stage; i < hw->x_end_stage; i++) {
 629                 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
 630                         > (ad714x->sensor_val[i] / 10))
 631                         return 1;
 632         }
 633
 634         for (i = hw->y_start_stage; i < sw->y_highest_stage; i++) {
 635                 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
 636                         > (ad714x->sensor_val[i + 1] / 10))
 637                         return 1;
 638         }
 639
 640         for (i = sw->y_highest_stage; i < hw->y_end_stage; i++) {
 641                 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
 642                         > (ad714x->sensor_val[i] / 10))
 643                         return 1;
 644         }
 645
 646         return 0;
 647 }
 648
 649 /*
 650  * If only one finger is used to activate the touch pad then only 1 peak will be
 651  * registered in the distribution. This peak and the 2 adjacent sensors will be
 652  * used in the calculation of the absolute position. This will prevent hand
 653  * shadows to affect the absolute position calculation.
 654  */
 655 static void touchpad_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
 656 {
 657         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 658         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 659
 660         sw->x_abs_pos = ad714x_cal_abs_pos(ad714x, hw->x_start_stage,
 661                         hw->x_end_stage, sw->x_highest_stage, hw->x_max_coord);
 662         sw->y_abs_pos = ad714x_cal_abs_pos(ad714x, hw->y_start_stage,
 663                         hw->y_end_stage, sw->y_highest_stage, hw->y_max_coord);
 664
 665         dev_dbg(ad714x->dev, "touchpad %d absolute position:(%d, %d)\n", idx,
 666                         sw->x_abs_pos, sw->y_abs_pos);
 667 }
 668
 669 static void touchpad_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
 670 {
 671         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 672
 673         sw->x_flt_pos = (sw->x_flt_pos * (10 - 4) +
 674                         sw->x_abs_pos * 4)/10;
 675         sw->y_flt_pos = (sw->y_flt_pos * (10 - 4) +
 676                         sw->y_abs_pos * 4)/10;
 677
 678         dev_dbg(ad714x->dev, "touchpad %d filter position:(%d, %d)\n",
 679                         idx, sw->x_flt_pos, sw->y_flt_pos);
 680 }
 681
 682 /*
 683  * To prevent distortion from showing in the absolute position, it is
 684  * necessary to detect the end points. When endpoints are detected, the
 685  * driver stops updating the status variables with absolute positions.
 686  * End points are detected on the 4 edges of the touchpad sensor. The
 687  * method to detect them is the same for all 4.
 688  * To detect the end points, the firmware computes the difference in
 689  * percent between the sensor on the edge and the adjacent one. The
 690  * difference is calculated in percent in order to make the end point
 691  * detection independent of the pressure.
 692  */
 693
 694 #define LEFT_END_POINT_DETECTION_LEVEL                  550
 695 #define RIGHT_END_POINT_DETECTION_LEVEL                 750
 696 #define LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL         850
 697 #define TOP_END_POINT_DETECTION_LEVEL                   550
 698 #define BOTTOM_END_POINT_DETECTION_LEVEL                950
 699 #define TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL         700
 700 static int touchpad_check_endpoint(struct ad714x_chip *ad714x, int idx)
 701 {
 702         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 703         struct ad714x_touchpad_drv *sw  = &ad714x->sw->touchpad[idx];
 704         int percent_sensor_diff;
 705
 706         /* left endpoint detect */
 707         percent_sensor_diff = (ad714x->sensor_val[hw->x_start_stage] -
 708                         ad714x->sensor_val[hw->x_start_stage + 1]) * 100 /
 709                         ad714x->sensor_val[hw->x_start_stage + 1];
 710         if (!sw->left_ep) {
 711                 if (percent_sensor_diff >= LEFT_END_POINT_DETECTION_LEVEL)  {
 712                         sw->left_ep = 1;
 713                         sw->left_ep_val =
 714                                 ad714x->sensor_val[hw->x_start_stage + 1];
 715                 }
 716         } else {
 717                 if ((percent_sensor_diff < LEFT_END_POINT_DETECTION_LEVEL) &&
 718                     (ad714x->sensor_val[hw->x_start_stage + 1] >
 719                      LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->left_ep_val))
 720                         sw->left_ep = 0;
 721         }
 722
 723         /* right endpoint detect */
 724         percent_sensor_diff = (ad714x->sensor_val[hw->x_end_stage] -
 725                         ad714x->sensor_val[hw->x_end_stage - 1]) * 100 /
 726                         ad714x->sensor_val[hw->x_end_stage - 1];
 727         if (!sw->right_ep) {
 728                 if (percent_sensor_diff >= RIGHT_END_POINT_DETECTION_LEVEL)  {
 729                         sw->right_ep = 1;
 730                         sw->right_ep_val =
 731                                 ad714x->sensor_val[hw->x_end_stage - 1];
 732                 }
 733         } else {
 734                 if ((percent_sensor_diff < RIGHT_END_POINT_DETECTION_LEVEL) &&
 735                 (ad714x->sensor_val[hw->x_end_stage - 1] >
 736                 LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->right_ep_val))
 737                         sw->right_ep = 0;
 738         }
 739
 740         /* top endpoint detect */
 741         percent_sensor_diff = (ad714x->sensor_val[hw->y_start_stage] -
 742                         ad714x->sensor_val[hw->y_start_stage + 1]) * 100 /
 743                         ad714x->sensor_val[hw->y_start_stage + 1];
 744         if (!sw->top_ep) {
 745                 if (percent_sensor_diff >= TOP_END_POINT_DETECTION_LEVEL)  {
 746                         sw->top_ep = 1;
 747                         sw->top_ep_val =
 748                                 ad714x->sensor_val[hw->y_start_stage + 1];
 749                 }
 750         } else {
 751                 if ((percent_sensor_diff < TOP_END_POINT_DETECTION_LEVEL) &&
 752                 (ad714x->sensor_val[hw->y_start_stage + 1] >
 753                 TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->top_ep_val))
 754                         sw->top_ep = 0;
 755         }
 756
 757         /* bottom endpoint detect */
 758         percent_sensor_diff = (ad714x->sensor_val[hw->y_end_stage] -
 759                 ad714x->sensor_val[hw->y_end_stage - 1]) * 100 /
 760                 ad714x->sensor_val[hw->y_end_stage - 1];
 761         if (!sw->bottom_ep) {
 762                 if (percent_sensor_diff >= BOTTOM_END_POINT_DETECTION_LEVEL)  {
 763                         sw->bottom_ep = 1;
 764                         sw->bottom_ep_val =
 765                                 ad714x->sensor_val[hw->y_end_stage - 1];
 766                 }
 767         } else {
 768                 if ((percent_sensor_diff < BOTTOM_END_POINT_DETECTION_LEVEL) &&
 769                 (ad714x->sensor_val[hw->y_end_stage - 1] >
 770                  TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->bottom_ep_val))
 771                         sw->bottom_ep = 0;
 772         }
 773
 774         return sw->left_ep || sw->right_ep || sw->top_ep || sw->bottom_ep;
 775 }
 776
 777 static void touchpad_use_com_int(struct ad714x_chip *ad714x, int idx)
 778 {
 779         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 780
 781         ad714x_use_com_int(ad714x, hw->x_start_stage, hw->x_end_stage);
 782 }
 783
 784 static void touchpad_use_thr_int(struct ad714x_chip *ad714x, int idx)
 785 {
 786         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 787
 788         ad714x_use_thr_int(ad714x, hw->x_start_stage, hw->x_end_stage);
 789         ad714x_use_thr_int(ad714x, hw->y_start_stage, hw->y_end_stage);
 790 }
 791
 792 static void ad714x_touchpad_state_machine(struct ad714x_chip *ad714x, int idx)
 793 {
 794         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 795         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 796         unsigned short h_state, c_state;
 797         unsigned short mask;
 798
 799         mask = (((1 << (hw->x_end_stage + 1)) - 1) -
 800                 ((1 << hw->x_start_stage) - 1)) +
 801                 (((1 << (hw->y_end_stage + 1)) - 1) -
 802                 ((1 << hw->y_start_stage) - 1));
 803
 804         h_state = ad714x->h_state & mask;
 805         c_state = ad714x->c_state & mask;
 806
 807         switch (sw->state) {
 808         case IDLE:
 809                 if (h_state) {
 810                         sw->state = JITTER;
 811                         /* In End of Conversion interrupt mode, the AD714X
 812                          * continuously generates hardware interrupts.
 813                          */
 814                         touchpad_use_com_int(ad714x, idx);
 815                         dev_dbg(ad714x->dev, "touchpad %d touched\n", idx);
 816                 }
 817                 break;
 818
 819         case JITTER:
 820                 if (c_state == mask) {
 821                         touchpad_cal_sensor_val(ad714x, idx);
 822                         touchpad_cal_highest_stage(ad714x, idx);
 823                         if ((!touchpad_check_second_peak(ad714x, idx)) &&
 824                                 (!touchpad_check_endpoint(ad714x, idx))) {
 825                                 dev_dbg(ad714x->dev,
 826                                         "touchpad%d, 2 fingers or endpoint\n",
 827                                         idx);
 828                                 touchpad_cal_abs_pos(ad714x, idx);
 829                                 sw->x_flt_pos = sw->x_abs_pos;
 830                                 sw->y_flt_pos = sw->y_abs_pos;
 831                                 sw->state = ACTIVE;
 832                         }
 833                 }
 834                 break;
 835
 836         case ACTIVE:
 837                 if (c_state == mask) {
 838                         if (h_state) {
 839                                 touchpad_cal_sensor_val(ad714x, idx);
 840                                 touchpad_cal_highest_stage(ad714x, idx);
 841                                 if ((!touchpad_check_second_peak(ad714x, idx))
 842                                   && (!touchpad_check_endpoint(ad714x, idx))) {
 843                                         touchpad_cal_abs_pos(ad714x, idx);
 844                                         touchpad_cal_flt_pos(ad714x, idx);
 845                                         input_report_abs(sw->input, ABS_X,
 846                                                 sw->x_flt_pos);
 847                                         input_report_abs(sw->input, ABS_Y,
 848                                                 sw->y_flt_pos);
 849                                         input_report_key(sw->input, BTN_TOUCH,
 850                                                 1);
 851                                 }
 852                         } else {
 853                                 /* When the user lifts off the sensor, configure
 854                                  * the AD714X back to threshold interrupt mode.
 855                                  */
 856                                 touchpad_use_thr_int(ad714x, idx);
 857                                 sw->state = IDLE;
 858                                 input_report_key(sw->input, BTN_TOUCH, 0);
 859                                 dev_dbg(ad714x->dev, "touchpad %d released\n",
 860                                         idx);
 861                         }
 862                         input_sync(sw->input);
 863                 }
 864                 break;
 865
 866         default:
 867                 break;
 868         }
 869 }
 870
 871 static int ad714x_hw_detect(struct ad714x_chip *ad714x)
 872 {
 873         unsigned short data;
 874
 875         ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1);
 876         switch (data & 0xFFF0) {
 877         case AD7142_PARTID:
 878                 ad714x->product = 0x7142;
 879                 ad714x->version = data & 0xF;
 880                 dev_info(ad714x->dev, "found AD7142 captouch, rev:%d\n",
 881                                 ad714x->version);
 882                 return 0;
 883
 884         case AD7143_PARTID:
 885                 ad714x->product = 0x7143;
 886                 ad714x->version = data & 0xF;
 887                 dev_info(ad714x->dev, "found AD7143 captouch, rev:%d\n",
 888                                 ad714x->version);
 889                 return 0;
 890
 891         case AD7147_PARTID:
 892                 ad714x->product = 0x7147;
 893                 ad714x->version = data & 0xF;
 894                 dev_info(ad714x->dev, "found AD7147(A) captouch, rev:%d\n",
 895                                 ad714x->version);
 896                 return 0;
 897
 898         case AD7148_PARTID:
 899                 ad714x->product = 0x7148;
 900                 ad714x->version = data & 0xF;
 901                 dev_info(ad714x->dev, "found AD7148 captouch, rev:%d\n",
 902                                 ad714x->version);
 903                 return 0;
 904
 905         default:
 906                 dev_err(ad714x->dev,
 907                         "fail to detect AD714X captouch, read ID is %04x\n",
 908                         data);
 909                 return -ENODEV;
 910         }
 911 }
 912
 913 static void ad714x_hw_init(struct ad714x_chip *ad714x)
 914 {
 915         int i, j;
 916         unsigned short reg_base;
 917         unsigned short data;
 918
 919         /* configuration CDC and interrupts */
 920
 921         for (i = 0; i < STAGE_NUM; i++) {
 922                 reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
 923                 for (j = 0; j < STAGE_CFGREG_NUM; j++)
 924                         ad714x->write(ad714x, reg_base + j,
 925                                         ad714x->hw->stage_cfg_reg[i][j]);
 926         }
 927
 928         for (i = 0; i < SYS_CFGREG_NUM; i++)
 929                 ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
 930                         ad714x->hw->sys_cfg_reg[i]);
 931         for (i = 0; i < SYS_CFGREG_NUM; i++)
 932                 ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1);
 933
 934         ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
 935
 936         /* clear all interrupts */
 937         ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 938 }
 939
 940 static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
 941 {
 942         struct ad714x_chip *ad714x = data;
 943         int i;
 944
 945         mutex_lock(&ad714x->mutex);
 946
 947         ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 948
 949         for (i = 0; i < ad714x->hw->button_num; i++)
 950                 ad714x_button_state_machine(ad714x, i);
 951         for (i = 0; i < ad714x->hw->slider_num; i++)
 952                 ad714x_slider_state_machine(ad714x, i);
 953         for (i = 0; i < ad714x->hw->wheel_num; i++)
 954                 ad714x_wheel_state_machine(ad714x, i);
 955         for (i = 0; i < ad714x->hw->touchpad_num; i++)
 956                 ad714x_touchpad_state_machine(ad714x, i);
 957
 958         mutex_unlock(&ad714x->mutex);
 959
 960         return IRQ_HANDLED;
 961 }
 962
 963 struct ad714x_chip *ad714x_probe(struct device *dev, u16 bus_type, int irq,
 964                                  ad714x_read_t read, ad714x_write_t write)
 965 {
 966         int i;
 967         int error;
 968         struct input_dev *input;
 969
 970         struct ad714x_platform_data *plat_data = dev_get_platdata(dev);
 971         struct ad714x_chip *ad714x;
 972         void *drv_mem;
 973         unsigned long irqflags;
 974
 975         struct ad714x_button_drv *bt_drv;
 976         struct ad714x_slider_drv *sd_drv;
 977         struct ad714x_wheel_drv *wl_drv;
 978         struct ad714x_touchpad_drv *tp_drv;
 979
 980
 981         if (irq <= 0) {
 982                 dev_err(dev, "IRQ not configured!\n");
 983                 error = -EINVAL;
 984                 return ERR_PTR(error);
 985         }
 986
 987         if (dev_get_platdata(dev) == NULL) {
 988                 dev_err(dev, "platform data for ad714x doesn't exist\n");
 989                 error = -EINVAL;
 990                 return ERR_PTR(error);
 991         }
 992
 993         ad714x = devm_kzalloc(dev, sizeof(*ad714x) + sizeof(*ad714x->sw) +
 994                                    sizeof(*sd_drv) * plat_data->slider_num +
 995                                    sizeof(*wl_drv) * plat_data->wheel_num +
 996                                    sizeof(*tp_drv) * plat_data->touchpad_num +
 997                                    sizeof(*bt_drv) * plat_data->button_num,
 998                               GFP_KERNEL);
 999         if (!ad714x) {
1000                 error = -ENOMEM;
1001                 return ERR_PTR(error);
1002         }
1003         ad714x->hw = plat_data;
1004
1005         drv_mem = ad714x + 1;
1006         ad714x->sw = drv_mem;
1007         drv_mem += sizeof(*ad714x->sw);
1008         ad714x->sw->slider = sd_drv = drv_mem;
1009         drv_mem += sizeof(*sd_drv) * ad714x->hw->slider_num;
1010         ad714x->sw->wheel = wl_drv = drv_mem;
1011         drv_mem += sizeof(*wl_drv) * ad714x->hw->wheel_num;
1012         ad714x->sw->touchpad = tp_drv = drv_mem;
1013         drv_mem += sizeof(*tp_drv) * ad714x->hw->touchpad_num;
1014         ad714x->sw->button = bt_drv = drv_mem;
1015         drv_mem += sizeof(*bt_drv) * ad714x->hw->button_num;
1016
1017         ad714x->read = read;
1018         ad714x->write = write;
1019         ad714x->irq = irq;
1020         ad714x->dev = dev;
1021
1022         error = ad714x_hw_detect(ad714x);
1023         if (error)
1024                 return ERR_PTR(error);
1025
1026         /* initialize and request sw/hw resources */
1027
1028         ad714x_hw_init(ad714x);
1029         mutex_init(&ad714x->mutex);
1030
1031         /* a slider uses one input_dev instance */
1032         if (ad714x->hw->slider_num > 0) {
1033                 struct ad714x_slider_plat *sd_plat = ad714x->hw->slider;
1034
1035                 for (i = 0; i < ad714x->hw->slider_num; i++) {
1036                         input = devm_input_allocate_device(dev);
1037                         if (!input)
1038                                 return ERR_PTR(-ENOMEM);
1039
1040                         __set_bit(EV_ABS, input->evbit);
1041                         __set_bit(EV_KEY, input->evbit);
1042                         __set_bit(ABS_X, input->absbit);
1043                         __set_bit(BTN_TOUCH, input->keybit);
1044                         input_set_abs_params(input,
1045                                 ABS_X, 0, sd_plat->max_coord, 0, 0);
1046
1047                         input->id.bustype = bus_type;
1048                         input->id.product = ad714x->product;
1049                         input->id.version = ad714x->version;
1050                         input->name = "ad714x_captouch_slider";
1051                         input->dev.parent = dev;
1052
1053                         error = input_register_device(input);
1054                         if (error)
1055                                 return ERR_PTR(error);
1056
1057                         sd_drv[i].input = input;
1058                 }
1059         }
1060
1061         /* a wheel uses one input_dev instance */
1062         if (ad714x->hw->wheel_num > 0) {
1063                 struct ad714x_wheel_plat *wl_plat = ad714x->hw->wheel;
1064
1065                 for (i = 0; i < ad714x->hw->wheel_num; i++) {
1066                         input = devm_input_allocate_device(dev);
1067                         if (!input)
1068                                 return ERR_PTR(-ENOMEM);
1069
1070                         __set_bit(EV_KEY, input->evbit);
1071                         __set_bit(EV_ABS, input->evbit);
1072                         __set_bit(ABS_WHEEL, input->absbit);
1073                         __set_bit(BTN_TOUCH, input->keybit);
1074                         input_set_abs_params(input,
1075                                 ABS_WHEEL, 0, wl_plat->max_coord, 0, 0);
1076
1077                         input->id.bustype = bus_type;
1078                         input->id.product = ad714x->product;
1079                         input->id.version = ad714x->version;
1080                         input->name = "ad714x_captouch_wheel";
1081                         input->dev.parent = dev;
1082
1083                         error = input_register_device(input);
1084                         if (error)
1085                                 return ERR_PTR(error);
1086
1087                         wl_drv[i].input = input;
1088                 }
1089         }
1090
1091         /* a touchpad uses one input_dev instance */
1092         if (ad714x->hw->touchpad_num > 0) {
1093                 struct ad714x_touchpad_plat *tp_plat = ad714x->hw->touchpad;
1094
1095                 for (i = 0; i < ad714x->hw->touchpad_num; i++) {
1096                         input = devm_input_allocate_device(dev);
1097                         if (!input)
1098                                 return ERR_PTR(-ENOMEM);
1099
1100                         __set_bit(EV_ABS, input->evbit);
1101                         __set_bit(EV_KEY, input->evbit);
1102                         __set_bit(ABS_X, input->absbit);
1103                         __set_bit(ABS_Y, input->absbit);
1104                         __set_bit(BTN_TOUCH, input->keybit);
1105                         input_set_abs_params(input,
1106                                 ABS_X, 0, tp_plat->x_max_coord, 0, 0);
1107                         input_set_abs_params(input,
1108                                 ABS_Y, 0, tp_plat->y_max_coord, 0, 0);
1109
1110                         input->id.bustype = bus_type;
1111                         input->id.product = ad714x->product;
1112                         input->id.version = ad714x->version;
1113                         input->name = "ad714x_captouch_pad";
1114                         input->dev.parent = dev;
1115
1116                         error = input_register_device(input);
1117                         if (error)
1118                                 return ERR_PTR(error);
1119
1120                         tp_drv[i].input = input;
1121                 }
1122         }
1123
1124         /* all buttons use one input node */
1125         if (ad714x->hw->button_num > 0) {
1126                 struct ad714x_button_plat *bt_plat = ad714x->hw->button;
1127
1128                 input = devm_input_allocate_device(dev);
1129                 if (!input) {
1130                         error = -ENOMEM;
1131                         return ERR_PTR(error);
1132                 }
1133
1134                 __set_bit(EV_KEY, input->evbit);
1135                 for (i = 0; i < ad714x->hw->button_num; i++) {
1136                         bt_drv[i].input = input;
1137                         __set_bit(bt_plat[i].keycode, input->keybit);
1138                 }
1139
1140                 input->id.bustype = bus_type;
1141                 input->id.product = ad714x->product;
1142                 input->id.version = ad714x->version;
1143                 input->name = "ad714x_captouch_button";
1144                 input->dev.parent = dev;
1145
1146                 error = input_register_device(input);
1147                 if (error)
1148                         return ERR_PTR(error);
1149         }
1150
1151         irqflags = plat_data->irqflags ?: IRQF_TRIGGER_FALLING;
1152         irqflags |= IRQF_ONESHOT;
1153
1154         error = devm_request_threaded_irq(dev, ad714x->irq, NULL,
1155                                           ad714x_interrupt_thread,
1156                                           irqflags, "ad714x_captouch", ad714x);
1157         if (error) {
1158                 dev_err(dev, "can't allocate irq %d\n", ad714x->irq);
1159                 return ERR_PTR(error);
1160         }
1161
1162         return ad714x;
1163 }
1164 EXPORT_SYMBOL(ad714x_probe);
1165
1166 #ifdef CONFIG_PM
1167 int ad714x_disable(struct ad714x_chip *ad714x)
1168 {
1169         unsigned short data;
1170
1171         dev_dbg(ad714x->dev, "%s enter\n", __func__);
1172
1173         mutex_lock(&ad714x->mutex);
1174
1175         data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
1176         ad714x->write(ad714x, AD714X_PWR_CTRL, data);
1177
1178         mutex_unlock(&ad714x->mutex);
1179
1180         return 0;
1181 }
1182 EXPORT_SYMBOL(ad714x_disable);
1183
1184 int ad714x_enable(struct ad714x_chip *ad714x)
1185 {
1186         dev_dbg(ad714x->dev, "%s enter\n", __func__);
1187
1188         mutex_lock(&ad714x->mutex);
1189
1190         /* resume to non-shutdown mode */
1191
1192         ad714x->write(ad714x, AD714X_PWR_CTRL,
1193                         ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);
1194
1195         /* make sure the interrupt output line is not low level after resume,
1196          * otherwise we will get no chance to enter falling-edge irq again
1197          */
1198
1199         ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
1200
1201         mutex_unlock(&ad714x->mutex);
1202
1203         return 0;
1204 }
1205 EXPORT_SYMBOL(ad714x_enable);
1206 #endif
1207
1208 MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor Driver");
1209 MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
1210 MODULE_LICENSE("GPL");