drivers/input/misc/ad714x.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A
   4  *
   5  * Copyright 2009-2011 Analog Devices Inc.
   6  */
   7
   8 #include <linux/device.h>
   9 #include <linux/input.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/slab.h>
  12 #include <linux/input/ad714x.h>
  13 #include <linux/module.h>
  14 #include "ad714x.h"
  15
  16 #define AD714X_PWR_CTRL           0x0
  17 #define AD714X_STG_CAL_EN_REG     0x1
  18 #define AD714X_AMB_COMP_CTRL0_REG 0x2
  19 #define AD714X_PARTID_REG         0x17
  20 #define AD7142_PARTID             0xE620
  21 #define AD7143_PARTID             0xE630
  22 #define AD7147_PARTID             0x1470
  23 #define AD7148_PARTID             0x1480
  24 #define AD714X_STAGECFG_REG       0x80
  25 #define AD714X_SYSCFG_REG         0x0
  26
  27 #define STG_LOW_INT_EN_REG     0x5
  28 #define STG_HIGH_INT_EN_REG    0x6
  29 #define STG_COM_INT_EN_REG     0x7
  30 #define STG_LOW_INT_STA_REG    0x8
  31 #define STG_HIGH_INT_STA_REG   0x9
  32 #define STG_COM_INT_STA_REG    0xA
  33
  34 #define CDC_RESULT_S0          0xB
  35 #define CDC_RESULT_S1          0xC
  36 #define CDC_RESULT_S2          0xD
  37 #define CDC_RESULT_S3          0xE
  38 #define CDC_RESULT_S4          0xF
  39 #define CDC_RESULT_S5          0x10
  40 #define CDC_RESULT_S6          0x11
  41 #define CDC_RESULT_S7          0x12
  42 #define CDC_RESULT_S8          0x13
  43 #define CDC_RESULT_S9          0x14
  44 #define CDC_RESULT_S10         0x15
  45 #define CDC_RESULT_S11         0x16
  46
  47 #define STAGE0_AMBIENT          0xF1
  48 #define STAGE1_AMBIENT          0x115
  49 #define STAGE2_AMBIENT          0x139
  50 #define STAGE3_AMBIENT          0x15D
  51 #define STAGE4_AMBIENT          0x181
  52 #define STAGE5_AMBIENT          0x1A5
  53 #define STAGE6_AMBIENT          0x1C9
  54 #define STAGE7_AMBIENT          0x1ED
  55 #define STAGE8_AMBIENT          0x211
  56 #define STAGE9_AMBIENT          0x234
  57 #define STAGE10_AMBIENT         0x259
  58 #define STAGE11_AMBIENT         0x27D
  59
  60 #define PER_STAGE_REG_NUM      36
  61 #define STAGE_CFGREG_NUM       8
  62 #define SYS_CFGREG_NUM         8
  63
  64 /*
  65  * driver information which will be used to maintain the software flow
  66  */
  67 enum ad714x_device_state { IDLE, JITTER, ACTIVE, SPACE };
  68
  69 struct ad714x_slider_drv {
  70         int highest_stage;
  71         int abs_pos;
  72         int flt_pos;
  73         enum ad714x_device_state state;
  74         struct input_dev *input;
  75 };
  76
  77 struct ad714x_wheel_drv {
  78         int abs_pos;
  79         int flt_pos;
  80         int pre_highest_stage;
  81         int highest_stage;
  82         enum ad714x_device_state state;
  83         struct input_dev *input;
  84 };
  85
  86 struct ad714x_touchpad_drv {
  87         int x_highest_stage;
  88         int x_flt_pos;
  89         int x_abs_pos;
  90         int y_highest_stage;
  91         int y_flt_pos;
  92         int y_abs_pos;
  93         int left_ep;
  94         int left_ep_val;
  95         int right_ep;
  96         int right_ep_val;
  97         int top_ep;
  98         int top_ep_val;
  99         int bottom_ep;
 100         int bottom_ep_val;
 101         enum ad714x_device_state state;
 102         struct input_dev *input;
 103 };
 104
 105 struct ad714x_button_drv {
 106         enum ad714x_device_state state;
 107         /*
 108          * Unlike slider/wheel/touchpad, all buttons point to
 109          * same input_dev instance
 110          */
 111         struct input_dev *input;
 112 };
 113
 114 struct ad714x_driver_data {
 115         struct ad714x_slider_drv *slider;
 116         struct ad714x_wheel_drv *wheel;
 117         struct ad714x_touchpad_drv *touchpad;
 118         struct ad714x_button_drv *button;
 119 };
 120
 121 /*
 122  * information to integrate all things which will be private data
 123  * of spi/i2c device
 124  */
 125
 126 static void ad714x_use_com_int(struct ad714x_chip *ad714x,
 127                                 int start_stage, int end_stage)
 128 {
 129         unsigned short data;
 130         unsigned short mask;
 131
 132         mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 133
 134         ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
 135         data |= 1 << end_stage;
 136         ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 137
 138         ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
 139         data &= ~mask;
 140         ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 141 }
 142
 143 static void ad714x_use_thr_int(struct ad714x_chip *ad714x,
 144                                 int start_stage, int end_stage)
 145 {
 146         unsigned short data;
 147         unsigned short mask;
 148
 149         mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1);
 150
 151         ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1);
 152         data &= ~(1 << end_stage);
 153         ad714x->write(ad714x, STG_COM_INT_EN_REG, data);
 154
 155         ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1);
 156         data |= mask;
 157         ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data);
 158 }
 159
 160 static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x,
 161                                         int start_stage, int end_stage)
 162 {
 163         int max_res = 0;
 164         int max_idx = 0;
 165         int i;
 166
 167         for (i = start_stage; i <= end_stage; i++) {
 168                 if (ad714x->sensor_val[i] > max_res) {
 169                         max_res = ad714x->sensor_val[i];
 170                         max_idx = i;
 171                 }
 172         }
 173
 174         return max_idx;
 175 }
 176
 177 static int ad714x_cal_abs_pos(struct ad714x_chip *ad714x,
 178                                 int start_stage, int end_stage,
 179                                 int highest_stage, int max_coord)
 180 {
 181         int a_param, b_param;
 182
 183         if (highest_stage == start_stage) {
 184                 a_param = ad714x->sensor_val[start_stage + 1];
 185                 b_param = ad714x->sensor_val[start_stage] +
 186                         ad714x->sensor_val[start_stage + 1];
 187         } else if (highest_stage == end_stage) {
 188                 a_param = ad714x->sensor_val[end_stage] *
 189                         (end_stage - start_stage) +
 190                         ad714x->sensor_val[end_stage - 1] *
 191                         (end_stage - start_stage - 1);
 192                 b_param = ad714x->sensor_val[end_stage] +
 193                         ad714x->sensor_val[end_stage - 1];
 194         } else {
 195                 a_param = ad714x->sensor_val[highest_stage] *
 196                         (highest_stage - start_stage) +
 197                         ad714x->sensor_val[highest_stage - 1] *
 198                         (highest_stage - start_stage - 1) +
 199                         ad714x->sensor_val[highest_stage + 1] *
 200                         (highest_stage - start_stage + 1);
 201                 b_param = ad714x->sensor_val[highest_stage] +
 202                         ad714x->sensor_val[highest_stage - 1] +
 203                         ad714x->sensor_val[highest_stage + 1];
 204         }
 205
 206         return (max_coord / (end_stage - start_stage)) * a_param / b_param;
 207 }
 208
 209 /*
 210  * One button can connect to multi positive and negative of CDCs
 211  * Multi-buttons can connect to same positive/negative of one CDC
 212  */
 213 static void ad714x_button_state_machine(struct ad714x_chip *ad714x, int idx)
 214 {
 215         struct ad714x_button_plat *hw = &ad714x->hw->button[idx];
 216         struct ad714x_button_drv *sw = &ad714x->sw->button[idx];
 217
 218         switch (sw->state) {
 219         case IDLE:
 220                 if (((ad714x->h_state & hw->h_mask) == hw->h_mask) &&
 221                     ((ad714x->l_state & hw->l_mask) == hw->l_mask)) {
 222                         dev_dbg(ad714x->dev, "button %d touched\n", idx);
 223                         input_report_key(sw->input, hw->keycode, 1);
 224                         input_sync(sw->input);
 225                         sw->state = ACTIVE;
 226                 }
 227                 break;
 228
 229         case ACTIVE:
 230                 if (((ad714x->h_state & hw->h_mask) != hw->h_mask) ||
 231                     ((ad714x->l_state & hw->l_mask) != hw->l_mask)) {
 232                         dev_dbg(ad714x->dev, "button %d released\n", idx);
 233                         input_report_key(sw->input, hw->keycode, 0);
 234                         input_sync(sw->input);
 235                         sw->state = IDLE;
 236                 }
 237                 break;
 238
 239         default:
 240                 break;
 241         }
 242 }
 243
 244 /*
 245  * The response of a sensor is defined by the absolute number of codes
 246  * between the current CDC value and the ambient value.
 247  */
 248 static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 249 {
 250         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 251         int i;
 252
 253         ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
 254                         &ad714x->adc_reg[hw->start_stage],
 255                         hw->end_stage - hw->start_stage + 1);
 256
 257         for (i = hw->start_stage; i <= hw->end_stage; i++) {
 258                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 259                                 &ad714x->amb_reg[i], 1);
 260
 261                 ad714x->sensor_val[i] =
 262                         abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]);
 263         }
 264 }
 265
 266 static void ad714x_slider_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
 267 {
 268         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 269         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 270
 271         sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
 272                         hw->end_stage);
 273
 274         dev_dbg(ad714x->dev, "slider %d highest_stage:%d\n", idx,
 275                 sw->highest_stage);
 276 }
 277
 278 /*
 279  * The formulae are very straight forward. It uses the sensor with the
 280  * highest response and the 2 adjacent ones.
 281  * When Sensor 0 has the highest response, only sensor 0 and sensor 1
 282  * are used in the calculations. Similarly when the last sensor has the
 283  * highest response, only the last sensor and the second last sensors
 284  * are used in the calculations.
 285  *
 286  * For i= idx_of_peak_Sensor-1 to i= idx_of_peak_Sensor+1
 287  *         v += Sensor response(i)*i
 288  *         w += Sensor response(i)
 289  * POS=(Number_of_Positions_Wanted/(Number_of_Sensors_Used-1)) *(v/w)
 290  */
 291 static void ad714x_slider_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
 292 {
 293         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 294         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 295
 296         sw->abs_pos = ad714x_cal_abs_pos(ad714x, hw->start_stage, hw->end_stage,
 297                 sw->highest_stage, hw->max_coord);
 298
 299         dev_dbg(ad714x->dev, "slider %d absolute position:%d\n", idx,
 300                 sw->abs_pos);
 301 }
 302
 303 /*
 304  * To minimise the Impact of the noise on the algorithm, ADI developed a
 305  * routine that filters the CDC results after they have been read by the
 306  * host processor.
 307  * The filter used is an Infinite Input Response(IIR) filter implemented
 308  * in firmware and attenuates the noise on the CDC results after they've
 309  * been read by the host processor.
 310  * Filtered_CDC_result = (Filtered_CDC_result * (10 - Coefficient) +
 311  *                              Latest_CDC_result * Coefficient)/10
 312  */
 313 static void ad714x_slider_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
 314 {
 315         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 316
 317         sw->flt_pos = (sw->flt_pos * (10 - 4) +
 318                         sw->abs_pos * 4)/10;
 319
 320         dev_dbg(ad714x->dev, "slider %d filter position:%d\n", idx,
 321                 sw->flt_pos);
 322 }
 323
 324 static void ad714x_slider_use_com_int(struct ad714x_chip *ad714x, int idx)
 325 {
 326         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 327
 328         ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
 329 }
 330
 331 static void ad714x_slider_use_thr_int(struct ad714x_chip *ad714x, int idx)
 332 {
 333         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 334
 335         ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
 336 }
 337
 338 static void ad714x_slider_state_machine(struct ad714x_chip *ad714x, int idx)
 339 {
 340         struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx];
 341         struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx];
 342         unsigned short h_state, c_state;
 343         unsigned short mask;
 344
 345         mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
 346
 347         h_state = ad714x->h_state & mask;
 348         c_state = ad714x->c_state & mask;
 349
 350         switch (sw->state) {
 351         case IDLE:
 352                 if (h_state) {
 353                         sw->state = JITTER;
 354                         /* In End of Conversion interrupt mode, the AD714X
 355                          * continuously generates hardware interrupts.
 356                          */
 357                         ad714x_slider_use_com_int(ad714x, idx);
 358                         dev_dbg(ad714x->dev, "slider %d touched\n", idx);
 359                 }
 360                 break;
 361
 362         case JITTER:
 363                 if (c_state == mask) {
 364                         ad714x_slider_cal_sensor_val(ad714x, idx);
 365                         ad714x_slider_cal_highest_stage(ad714x, idx);
 366                         ad714x_slider_cal_abs_pos(ad714x, idx);
 367                         sw->flt_pos = sw->abs_pos;
 368                         sw->state = ACTIVE;
 369                 }
 370                 break;
 371
 372         case ACTIVE:
 373                 if (c_state == mask) {
 374                         if (h_state) {
 375                                 ad714x_slider_cal_sensor_val(ad714x, idx);
 376                                 ad714x_slider_cal_highest_stage(ad714x, idx);
 377                                 ad714x_slider_cal_abs_pos(ad714x, idx);
 378                                 ad714x_slider_cal_flt_pos(ad714x, idx);
 379                                 input_report_abs(sw->input, ABS_X, sw->flt_pos);
 380                                 input_report_key(sw->input, BTN_TOUCH, 1);
 381                         } else {
 382                                 /* When the user lifts off the sensor, configure
 383                                  * the AD714X back to threshold interrupt mode.
 384                                  */
 385                                 ad714x_slider_use_thr_int(ad714x, idx);
 386                                 sw->state = IDLE;
 387                                 input_report_key(sw->input, BTN_TOUCH, 0);
 388                                 dev_dbg(ad714x->dev, "slider %d released\n",
 389                                         idx);
 390                         }
 391                         input_sync(sw->input);
 392                 }
 393                 break;
 394
 395         default:
 396                 break;
 397         }
 398 }
 399
 400 /*
 401  * When the scroll wheel is activated, we compute the absolute position based
 402  * on the sensor values. To calculate the position, we first determine the
 403  * sensor that has the greatest response among the 8 sensors that constitutes
 404  * the scrollwheel. Then we determined the 2 sensors on either sides of the
 405  * sensor with the highest response and we apply weights to these sensors.
 406  */
 407 static void ad714x_wheel_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
 408 {
 409         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 410         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 411
 412         sw->pre_highest_stage = sw->highest_stage;
 413         sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage,
 414                         hw->end_stage);
 415
 416         dev_dbg(ad714x->dev, "wheel %d highest_stage:%d\n", idx,
 417                 sw->highest_stage);
 418 }
 419
 420 static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 421 {
 422         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 423         int i;
 424
 425         ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage,
 426                         &ad714x->adc_reg[hw->start_stage],
 427                         hw->end_stage - hw->start_stage + 1);
 428
 429         for (i = hw->start_stage; i <= hw->end_stage; i++) {
 430                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 431                                 &ad714x->amb_reg[i], 1);
 432                 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
 433                         ad714x->sensor_val[i] =
 434                                 ad714x->adc_reg[i] - ad714x->amb_reg[i];
 435                 else
 436                         ad714x->sensor_val[i] = 0;
 437         }
 438 }
 439
 440 /*
 441  * When the scroll wheel is activated, we compute the absolute position based
 442  * on the sensor values. To calculate the position, we first determine the
 443  * sensor that has the greatest response among the sensors that constitutes
 444  * the scrollwheel. Then we determined the sensors on either sides of the
 445  * sensor with the highest response and we apply weights to these sensors. The
 446  * result of this computation gives us the mean value.
 447  */
 448
 449 static void ad714x_wheel_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
 450 {
 451         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 452         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 453         int stage_num = hw->end_stage - hw->start_stage + 1;
 454         int first_before, highest, first_after;
 455         int a_param, b_param;
 456
 457         first_before = (sw->highest_stage + stage_num - 1) % stage_num;
 458         highest = sw->highest_stage;
 459         first_after = (sw->highest_stage + stage_num + 1) % stage_num;
 460
 461         a_param = ad714x->sensor_val[highest] *
 462                 (highest - hw->start_stage) +
 463                 ad714x->sensor_val[first_before] *
 464                 (highest - hw->start_stage - 1) +
 465                 ad714x->sensor_val[first_after] *
 466                 (highest - hw->start_stage + 1);
 467         b_param = ad714x->sensor_val[highest] +
 468                 ad714x->sensor_val[first_before] +
 469                 ad714x->sensor_val[first_after];
 470
 471         sw->abs_pos = ((hw->max_coord / (hw->end_stage - hw->start_stage)) *
 472                         a_param) / b_param;
 473
 474         if (sw->abs_pos > hw->max_coord)
 475                 sw->abs_pos = hw->max_coord;
 476         else if (sw->abs_pos < 0)
 477                 sw->abs_pos = 0;
 478 }
 479
 480 static void ad714x_wheel_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
 481 {
 482         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 483         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 484         if (((sw->pre_highest_stage == hw->end_stage) &&
 485                         (sw->highest_stage == hw->start_stage)) ||
 486             ((sw->pre_highest_stage == hw->start_stage) &&
 487                         (sw->highest_stage == hw->end_stage)))
 488                 sw->flt_pos = sw->abs_pos;
 489         else
 490                 sw->flt_pos = ((sw->flt_pos * 30) + (sw->abs_pos * 71)) / 100;
 491
 492         if (sw->flt_pos > hw->max_coord)
 493                 sw->flt_pos = hw->max_coord;
 494 }
 495
 496 static void ad714x_wheel_use_com_int(struct ad714x_chip *ad714x, int idx)
 497 {
 498         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 499
 500         ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage);
 501 }
 502
 503 static void ad714x_wheel_use_thr_int(struct ad714x_chip *ad714x, int idx)
 504 {
 505         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 506
 507         ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage);
 508 }
 509
 510 static void ad714x_wheel_state_machine(struct ad714x_chip *ad714x, int idx)
 511 {
 512         struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx];
 513         struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx];
 514         unsigned short h_state, c_state;
 515         unsigned short mask;
 516
 517         mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1);
 518
 519         h_state = ad714x->h_state & mask;
 520         c_state = ad714x->c_state & mask;
 521
 522         switch (sw->state) {
 523         case IDLE:
 524                 if (h_state) {
 525                         sw->state = JITTER;
 526                         /* In End of Conversion interrupt mode, the AD714X
 527                          * continuously generates hardware interrupts.
 528                          */
 529                         ad714x_wheel_use_com_int(ad714x, idx);
 530                         dev_dbg(ad714x->dev, "wheel %d touched\n", idx);
 531                 }
 532                 break;
 533
 534         case JITTER:
 535                 if (c_state == mask)    {
 536                         ad714x_wheel_cal_sensor_val(ad714x, idx);
 537                         ad714x_wheel_cal_highest_stage(ad714x, idx);
 538                         ad714x_wheel_cal_abs_pos(ad714x, idx);
 539                         sw->flt_pos = sw->abs_pos;
 540                         sw->state = ACTIVE;
 541                 }
 542                 break;
 543
 544         case ACTIVE:
 545                 if (c_state == mask) {
 546                         if (h_state) {
 547                                 ad714x_wheel_cal_sensor_val(ad714x, idx);
 548                                 ad714x_wheel_cal_highest_stage(ad714x, idx);
 549                                 ad714x_wheel_cal_abs_pos(ad714x, idx);
 550                                 ad714x_wheel_cal_flt_pos(ad714x, idx);
 551                                 input_report_abs(sw->input, ABS_WHEEL,
 552                                         sw->flt_pos);
 553                                 input_report_key(sw->input, BTN_TOUCH, 1);
 554                         } else {
 555                                 /* When the user lifts off the sensor, configure
 556                                  * the AD714X back to threshold interrupt mode.
 557                                  */
 558                                 ad714x_wheel_use_thr_int(ad714x, idx);
 559                                 sw->state = IDLE;
 560                                 input_report_key(sw->input, BTN_TOUCH, 0);
 561
 562                                 dev_dbg(ad714x->dev, "wheel %d released\n",
 563                                         idx);
 564                         }
 565                         input_sync(sw->input);
 566                 }
 567                 break;
 568
 569         default:
 570                 break;
 571         }
 572 }
 573
 574 static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx)
 575 {
 576         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 577         int i;
 578
 579         ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage,
 580                         &ad714x->adc_reg[hw->x_start_stage],
 581                         hw->x_end_stage - hw->x_start_stage + 1);
 582
 583         for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) {
 584                 ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM,
 585                                 &ad714x->amb_reg[i], 1);
 586                 if (ad714x->adc_reg[i] > ad714x->amb_reg[i])
 587                         ad714x->sensor_val[i] =
 588                                 ad714x->adc_reg[i] - ad714x->amb_reg[i];
 589                 else
 590                         ad714x->sensor_val[i] = 0;
 591         }
 592 }
 593
 594 static void touchpad_cal_highest_stage(struct ad714x_chip *ad714x, int idx)
 595 {
 596         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 597         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 598
 599         sw->x_highest_stage = ad714x_cal_highest_stage(ad714x,
 600                 hw->x_start_stage, hw->x_end_stage);
 601         sw->y_highest_stage = ad714x_cal_highest_stage(ad714x,
 602                 hw->y_start_stage, hw->y_end_stage);
 603
 604         dev_dbg(ad714x->dev,
 605                 "touchpad %d x_highest_stage:%d, y_highest_stage:%d\n",
 606                 idx, sw->x_highest_stage, sw->y_highest_stage);
 607 }
 608
 609 /*
 610  * If 2 fingers are touching the sensor then 2 peaks can be observed in the
 611  * distribution.
 612  * The arithmetic doesn't support to get absolute coordinates for multi-touch
 613  * yet.
 614  */
 615 static int touchpad_check_second_peak(struct ad714x_chip *ad714x, int idx)
 616 {
 617         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 618         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 619         int i;
 620
 621         for (i = hw->x_start_stage; i < sw->x_highest_stage; i++) {
 622                 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
 623                         > (ad714x->sensor_val[i + 1] / 10))
 624                         return 1;
 625         }
 626
 627         for (i = sw->x_highest_stage; i < hw->x_end_stage; i++) {
 628                 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
 629                         > (ad714x->sensor_val[i] / 10))
 630                         return 1;
 631         }
 632
 633         for (i = hw->y_start_stage; i < sw->y_highest_stage; i++) {
 634                 if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1])
 635                         > (ad714x->sensor_val[i + 1] / 10))
 636                         return 1;
 637         }
 638
 639         for (i = sw->y_highest_stage; i < hw->y_end_stage; i++) {
 640                 if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i])
 641                         > (ad714x->sensor_val[i] / 10))
 642                         return 1;
 643         }
 644
 645         return 0;
 646 }
 647
 648 /*
 649  * If only one finger is used to activate the touch pad then only 1 peak will be
 650  * registered in the distribution. This peak and the 2 adjacent sensors will be
 651  * used in the calculation of the absolute position. This will prevent hand
 652  * shadows to affect the absolute position calculation.
 653  */
 654 static void touchpad_cal_abs_pos(struct ad714x_chip *ad714x, int idx)
 655 {
 656         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 657         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 658
 659         sw->x_abs_pos = ad714x_cal_abs_pos(ad714x, hw->x_start_stage,
 660                         hw->x_end_stage, sw->x_highest_stage, hw->x_max_coord);
 661         sw->y_abs_pos = ad714x_cal_abs_pos(ad714x, hw->y_start_stage,
 662                         hw->y_end_stage, sw->y_highest_stage, hw->y_max_coord);
 663
 664         dev_dbg(ad714x->dev, "touchpad %d absolute position:(%d, %d)\n", idx,
 665                         sw->x_abs_pos, sw->y_abs_pos);
 666 }
 667
 668 static void touchpad_cal_flt_pos(struct ad714x_chip *ad714x, int idx)
 669 {
 670         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 671
 672         sw->x_flt_pos = (sw->x_flt_pos * (10 - 4) +
 673                         sw->x_abs_pos * 4)/10;
 674         sw->y_flt_pos = (sw->y_flt_pos * (10 - 4) +
 675                         sw->y_abs_pos * 4)/10;
 676
 677         dev_dbg(ad714x->dev, "touchpad %d filter position:(%d, %d)\n",
 678                         idx, sw->x_flt_pos, sw->y_flt_pos);
 679 }
 680
 681 /*
 682  * To prevent distortion from showing in the absolute position, it is
 683  * necessary to detect the end points. When endpoints are detected, the
 684  * driver stops updating the status variables with absolute positions.
 685  * End points are detected on the 4 edges of the touchpad sensor. The
 686  * method to detect them is the same for all 4.
 687  * To detect the end points, the firmware computes the difference in
 688  * percent between the sensor on the edge and the adjacent one. The
 689  * difference is calculated in percent in order to make the end point
 690  * detection independent of the pressure.
 691  */
 692
 693 #define LEFT_END_POINT_DETECTION_LEVEL                  550
 694 #define RIGHT_END_POINT_DETECTION_LEVEL                 750
 695 #define LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL         850
 696 #define TOP_END_POINT_DETECTION_LEVEL                   550
 697 #define BOTTOM_END_POINT_DETECTION_LEVEL                950
 698 #define TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL         700
 699 static int touchpad_check_endpoint(struct ad714x_chip *ad714x, int idx)
 700 {
 701         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 702         struct ad714x_touchpad_drv *sw  = &ad714x->sw->touchpad[idx];
 703         int percent_sensor_diff;
 704
 705         /* left endpoint detect */
 706         percent_sensor_diff = (ad714x->sensor_val[hw->x_start_stage] -
 707                         ad714x->sensor_val[hw->x_start_stage + 1]) * 100 /
 708                         ad714x->sensor_val[hw->x_start_stage + 1];
 709         if (!sw->left_ep) {
 710                 if (percent_sensor_diff >= LEFT_END_POINT_DETECTION_LEVEL)  {
 711                         sw->left_ep = 1;
 712                         sw->left_ep_val =
 713                                 ad714x->sensor_val[hw->x_start_stage + 1];
 714                 }
 715         } else {
 716                 if ((percent_sensor_diff < LEFT_END_POINT_DETECTION_LEVEL) &&
 717                     (ad714x->sensor_val[hw->x_start_stage + 1] >
 718                      LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->left_ep_val))
 719                         sw->left_ep = 0;
 720         }
 721
 722         /* right endpoint detect */
 723         percent_sensor_diff = (ad714x->sensor_val[hw->x_end_stage] -
 724                         ad714x->sensor_val[hw->x_end_stage - 1]) * 100 /
 725                         ad714x->sensor_val[hw->x_end_stage - 1];
 726         if (!sw->right_ep) {
 727                 if (percent_sensor_diff >= RIGHT_END_POINT_DETECTION_LEVEL)  {
 728                         sw->right_ep = 1;
 729                         sw->right_ep_val =
 730                                 ad714x->sensor_val[hw->x_end_stage - 1];
 731                 }
 732         } else {
 733                 if ((percent_sensor_diff < RIGHT_END_POINT_DETECTION_LEVEL) &&
 734                 (ad714x->sensor_val[hw->x_end_stage - 1] >
 735                 LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->right_ep_val))
 736                         sw->right_ep = 0;
 737         }
 738
 739         /* top endpoint detect */
 740         percent_sensor_diff = (ad714x->sensor_val[hw->y_start_stage] -
 741                         ad714x->sensor_val[hw->y_start_stage + 1]) * 100 /
 742                         ad714x->sensor_val[hw->y_start_stage + 1];
 743         if (!sw->top_ep) {
 744                 if (percent_sensor_diff >= TOP_END_POINT_DETECTION_LEVEL)  {
 745                         sw->top_ep = 1;
 746                         sw->top_ep_val =
 747                                 ad714x->sensor_val[hw->y_start_stage + 1];
 748                 }
 749         } else {
 750                 if ((percent_sensor_diff < TOP_END_POINT_DETECTION_LEVEL) &&
 751                 (ad714x->sensor_val[hw->y_start_stage + 1] >
 752                 TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->top_ep_val))
 753                         sw->top_ep = 0;
 754         }
 755
 756         /* bottom endpoint detect */
 757         percent_sensor_diff = (ad714x->sensor_val[hw->y_end_stage] -
 758                 ad714x->sensor_val[hw->y_end_stage - 1]) * 100 /
 759                 ad714x->sensor_val[hw->y_end_stage - 1];
 760         if (!sw->bottom_ep) {
 761                 if (percent_sensor_diff >= BOTTOM_END_POINT_DETECTION_LEVEL)  {
 762                         sw->bottom_ep = 1;
 763                         sw->bottom_ep_val =
 764                                 ad714x->sensor_val[hw->y_end_stage - 1];
 765                 }
 766         } else {
 767                 if ((percent_sensor_diff < BOTTOM_END_POINT_DETECTION_LEVEL) &&
 768                 (ad714x->sensor_val[hw->y_end_stage - 1] >
 769                  TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->bottom_ep_val))
 770                         sw->bottom_ep = 0;
 771         }
 772
 773         return sw->left_ep || sw->right_ep || sw->top_ep || sw->bottom_ep;
 774 }
 775
 776 static void touchpad_use_com_int(struct ad714x_chip *ad714x, int idx)
 777 {
 778         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 779
 780         ad714x_use_com_int(ad714x, hw->x_start_stage, hw->x_end_stage);
 781 }
 782
 783 static void touchpad_use_thr_int(struct ad714x_chip *ad714x, int idx)
 784 {
 785         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 786
 787         ad714x_use_thr_int(ad714x, hw->x_start_stage, hw->x_end_stage);
 788         ad714x_use_thr_int(ad714x, hw->y_start_stage, hw->y_end_stage);
 789 }
 790
 791 static void ad714x_touchpad_state_machine(struct ad714x_chip *ad714x, int idx)
 792 {
 793         struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx];
 794         struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx];
 795         unsigned short h_state, c_state;
 796         unsigned short mask;
 797
 798         mask = (((1 << (hw->x_end_stage + 1)) - 1) -
 799                 ((1 << hw->x_start_stage) - 1)) +
 800                 (((1 << (hw->y_end_stage + 1)) - 1) -
 801                 ((1 << hw->y_start_stage) - 1));
 802
 803         h_state = ad714x->h_state & mask;
 804         c_state = ad714x->c_state & mask;
 805
 806         switch (sw->state) {
 807         case IDLE:
 808                 if (h_state) {
 809                         sw->state = JITTER;
 810                         /* In End of Conversion interrupt mode, the AD714X
 811                          * continuously generates hardware interrupts.
 812                          */
 813                         touchpad_use_com_int(ad714x, idx);
 814                         dev_dbg(ad714x->dev, "touchpad %d touched\n", idx);
 815                 }
 816                 break;
 817
 818         case JITTER:
 819                 if (c_state == mask) {
 820                         touchpad_cal_sensor_val(ad714x, idx);
 821                         touchpad_cal_highest_stage(ad714x, idx);
 822                         if ((!touchpad_check_second_peak(ad714x, idx)) &&
 823                                 (!touchpad_check_endpoint(ad714x, idx))) {
 824                                 dev_dbg(ad714x->dev,
 825                                         "touchpad%d, 2 fingers or endpoint\n",
 826                                         idx);
 827                                 touchpad_cal_abs_pos(ad714x, idx);
 828                                 sw->x_flt_pos = sw->x_abs_pos;
 829                                 sw->y_flt_pos = sw->y_abs_pos;
 830                                 sw->state = ACTIVE;
 831                         }
 832                 }
 833                 break;
 834
 835         case ACTIVE:
 836                 if (c_state == mask) {
 837                         if (h_state) {
 838                                 touchpad_cal_sensor_val(ad714x, idx);
 839                                 touchpad_cal_highest_stage(ad714x, idx);
 840                                 if ((!touchpad_check_second_peak(ad714x, idx))
 841                                   && (!touchpad_check_endpoint(ad714x, idx))) {
 842                                         touchpad_cal_abs_pos(ad714x, idx);
 843                                         touchpad_cal_flt_pos(ad714x, idx);
 844                                         input_report_abs(sw->input, ABS_X,
 845                                                 sw->x_flt_pos);
 846                                         input_report_abs(sw->input, ABS_Y,
 847                                                 sw->y_flt_pos);
 848                                         input_report_key(sw->input, BTN_TOUCH,
 849                                                 1);
 850                                 }
 851                         } else {
 852                                 /* When the user lifts off the sensor, configure
 853                                  * the AD714X back to threshold interrupt mode.
 854                                  */
 855                                 touchpad_use_thr_int(ad714x, idx);
 856                                 sw->state = IDLE;
 857                                 input_report_key(sw->input, BTN_TOUCH, 0);
 858                                 dev_dbg(ad714x->dev, "touchpad %d released\n",
 859                                         idx);
 860                         }
 861                         input_sync(sw->input);
 862                 }
 863                 break;
 864
 865         default:
 866                 break;
 867         }
 868 }
 869
 870 static int ad714x_hw_detect(struct ad714x_chip *ad714x)
 871 {
 872         unsigned short data;
 873
 874         ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1);
 875         switch (data & 0xFFF0) {
 876         case AD7142_PARTID:
 877                 ad714x->product = 0x7142;
 878                 ad714x->version = data & 0xF;
 879                 dev_info(ad714x->dev, "found AD7142 captouch, rev:%d\n",
 880                                 ad714x->version);
 881                 return 0;
 882
 883         case AD7143_PARTID:
 884                 ad714x->product = 0x7143;
 885                 ad714x->version = data & 0xF;
 886                 dev_info(ad714x->dev, "found AD7143 captouch, rev:%d\n",
 887                                 ad714x->version);
 888                 return 0;
 889
 890         case AD7147_PARTID:
 891                 ad714x->product = 0x7147;
 892                 ad714x->version = data & 0xF;
 893                 dev_info(ad714x->dev, "found AD7147(A) captouch, rev:%d\n",
 894                                 ad714x->version);
 895                 return 0;
 896
 897         case AD7148_PARTID:
 898                 ad714x->product = 0x7148;
 899                 ad714x->version = data & 0xF;
 900                 dev_info(ad714x->dev, "found AD7148 captouch, rev:%d\n",
 901                                 ad714x->version);
 902                 return 0;
 903
 904         default:
 905                 dev_err(ad714x->dev,
 906                         "fail to detect AD714X captouch, read ID is %04x\n",
 907                         data);
 908                 return -ENODEV;
 909         }
 910 }
 911
 912 static void ad714x_hw_init(struct ad714x_chip *ad714x)
 913 {
 914         int i, j;
 915         unsigned short reg_base;
 916         unsigned short data;
 917
 918         /* configuration CDC and interrupts */
 919
 920         for (i = 0; i < STAGE_NUM; i++) {
 921                 reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM;
 922                 for (j = 0; j < STAGE_CFGREG_NUM; j++)
 923                         ad714x->write(ad714x, reg_base + j,
 924                                         ad714x->hw->stage_cfg_reg[i][j]);
 925         }
 926
 927         for (i = 0; i < SYS_CFGREG_NUM; i++)
 928                 ad714x->write(ad714x, AD714X_SYSCFG_REG + i,
 929                         ad714x->hw->sys_cfg_reg[i]);
 930         for (i = 0; i < SYS_CFGREG_NUM; i++)
 931                 ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1);
 932
 933         ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF);
 934
 935         /* clear all interrupts */
 936         ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 937 }
 938
 939 static irqreturn_t ad714x_interrupt_thread(int irq, void *data)
 940 {
 941         struct ad714x_chip *ad714x = data;
 942         int i;
 943
 944         guard(mutex)(&ad714x->mutex);
 945
 946         ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
 947
 948         for (i = 0; i < ad714x->hw->button_num; i++)
 949                 ad714x_button_state_machine(ad714x, i);
 950         for (i = 0; i < ad714x->hw->slider_num; i++)
 951                 ad714x_slider_state_machine(ad714x, i);
 952         for (i = 0; i < ad714x->hw->wheel_num; i++)
 953                 ad714x_wheel_state_machine(ad714x, i);
 954         for (i = 0; i < ad714x->hw->touchpad_num; i++)
 955                 ad714x_touchpad_state_machine(ad714x, i);
 956
 957         return IRQ_HANDLED;
 958 }
 959
 960 struct ad714x_chip *ad714x_probe(struct device *dev, u16 bus_type, int irq,
 961                                  ad714x_read_t read, ad714x_write_t write)
 962 {
 963         int i;
 964         int error;
 965         struct input_dev *input;
 966
 967         struct ad714x_platform_data *plat_data = dev_get_platdata(dev);
 968         struct ad714x_chip *ad714x;
 969         void *drv_mem;
 970         unsigned long irqflags;
 971
 972         struct ad714x_button_drv *bt_drv;
 973         struct ad714x_slider_drv *sd_drv;
 974         struct ad714x_wheel_drv *wl_drv;
 975         struct ad714x_touchpad_drv *tp_drv;
 976
 977
 978         if (irq <= 0) {
 979                 dev_err(dev, "IRQ not configured!\n");
 980                 error = -EINVAL;
 981                 return ERR_PTR(error);
 982         }
 983
 984         if (dev_get_platdata(dev) == NULL) {
 985                 dev_err(dev, "platform data for ad714x doesn't exist\n");
 986                 error = -EINVAL;
 987                 return ERR_PTR(error);
 988         }
 989
 990         ad714x = devm_kzalloc(dev, sizeof(*ad714x) + sizeof(*ad714x->sw) +
 991                                    sizeof(*sd_drv) * plat_data->slider_num +
 992                                    sizeof(*wl_drv) * plat_data->wheel_num +
 993                                    sizeof(*tp_drv) * plat_data->touchpad_num +
 994                                    sizeof(*bt_drv) * plat_data->button_num,
 995                               GFP_KERNEL);
 996         if (!ad714x) {
 997                 error = -ENOMEM;
 998                 return ERR_PTR(error);
 999         }
1000         ad714x->hw = plat_data;
1001
1002         drv_mem = ad714x + 1;
1003         ad714x->sw = drv_mem;
1004         drv_mem += sizeof(*ad714x->sw);
1005         ad714x->sw->slider = sd_drv = drv_mem;
1006         drv_mem += sizeof(*sd_drv) * ad714x->hw->slider_num;
1007         ad714x->sw->wheel = wl_drv = drv_mem;
1008         drv_mem += sizeof(*wl_drv) * ad714x->hw->wheel_num;
1009         ad714x->sw->touchpad = tp_drv = drv_mem;
1010         drv_mem += sizeof(*tp_drv) * ad714x->hw->touchpad_num;
1011         ad714x->sw->button = bt_drv = drv_mem;
1012         drv_mem += sizeof(*bt_drv) * ad714x->hw->button_num;
1013
1014         ad714x->read = read;
1015         ad714x->write = write;
1016         ad714x->irq = irq;
1017         ad714x->dev = dev;
1018
1019         error = ad714x_hw_detect(ad714x);
1020         if (error)
1021                 return ERR_PTR(error);
1022
1023         /* initialize and request sw/hw resources */
1024
1025         ad714x_hw_init(ad714x);
1026         mutex_init(&ad714x->mutex);
1027
1028         /* a slider uses one input_dev instance */
1029         if (ad714x->hw->slider_num > 0) {
1030                 struct ad714x_slider_plat *sd_plat = ad714x->hw->slider;
1031
1032                 for (i = 0; i < ad714x->hw->slider_num; i++) {
1033                         input = devm_input_allocate_device(dev);
1034                         if (!input)
1035                                 return ERR_PTR(-ENOMEM);
1036
1037                         __set_bit(EV_ABS, input->evbit);
1038                         __set_bit(EV_KEY, input->evbit);
1039                         __set_bit(ABS_X, input->absbit);
1040                         __set_bit(BTN_TOUCH, input->keybit);
1041                         input_set_abs_params(input,
1042                                 ABS_X, 0, sd_plat->max_coord, 0, 0);
1043
1044                         input->id.bustype = bus_type;
1045                         input->id.product = ad714x->product;
1046                         input->id.version = ad714x->version;
1047                         input->name = "ad714x_captouch_slider";
1048                         input->dev.parent = dev;
1049
1050                         error = input_register_device(input);
1051                         if (error)
1052                                 return ERR_PTR(error);
1053
1054                         sd_drv[i].input = input;
1055                 }
1056         }
1057
1058         /* a wheel uses one input_dev instance */
1059         if (ad714x->hw->wheel_num > 0) {
1060                 struct ad714x_wheel_plat *wl_plat = ad714x->hw->wheel;
1061
1062                 for (i = 0; i < ad714x->hw->wheel_num; i++) {
1063                         input = devm_input_allocate_device(dev);
1064                         if (!input)
1065                                 return ERR_PTR(-ENOMEM);
1066
1067                         __set_bit(EV_KEY, input->evbit);
1068                         __set_bit(EV_ABS, input->evbit);
1069                         __set_bit(ABS_WHEEL, input->absbit);
1070                         __set_bit(BTN_TOUCH, input->keybit);
1071                         input_set_abs_params(input,
1072                                 ABS_WHEEL, 0, wl_plat->max_coord, 0, 0);
1073
1074                         input->id.bustype = bus_type;
1075                         input->id.product = ad714x->product;
1076                         input->id.version = ad714x->version;
1077                         input->name = "ad714x_captouch_wheel";
1078                         input->dev.parent = dev;
1079
1080                         error = input_register_device(input);
1081                         if (error)
1082                                 return ERR_PTR(error);
1083
1084                         wl_drv[i].input = input;
1085                 }
1086         }
1087
1088         /* a touchpad uses one input_dev instance */
1089         if (ad714x->hw->touchpad_num > 0) {
1090                 struct ad714x_touchpad_plat *tp_plat = ad714x->hw->touchpad;
1091
1092                 for (i = 0; i < ad714x->hw->touchpad_num; i++) {
1093                         input = devm_input_allocate_device(dev);
1094                         if (!input)
1095                                 return ERR_PTR(-ENOMEM);
1096
1097                         __set_bit(EV_ABS, input->evbit);
1098                         __set_bit(EV_KEY, input->evbit);
1099                         __set_bit(ABS_X, input->absbit);
1100                         __set_bit(ABS_Y, input->absbit);
1101                         __set_bit(BTN_TOUCH, input->keybit);
1102                         input_set_abs_params(input,
1103                                 ABS_X, 0, tp_plat->x_max_coord, 0, 0);
1104                         input_set_abs_params(input,
1105                                 ABS_Y, 0, tp_plat->y_max_coord, 0, 0);
1106
1107                         input->id.bustype = bus_type;
1108                         input->id.product = ad714x->product;
1109                         input->id.version = ad714x->version;
1110                         input->name = "ad714x_captouch_pad";
1111                         input->dev.parent = dev;
1112
1113                         error = input_register_device(input);
1114                         if (error)
1115                                 return ERR_PTR(error);
1116
1117                         tp_drv[i].input = input;
1118                 }
1119         }
1120
1121         /* all buttons use one input node */
1122         if (ad714x->hw->button_num > 0) {
1123                 struct ad714x_button_plat *bt_plat = ad714x->hw->button;
1124
1125                 input = devm_input_allocate_device(dev);
1126                 if (!input) {
1127                         error = -ENOMEM;
1128                         return ERR_PTR(error);
1129                 }
1130
1131                 __set_bit(EV_KEY, input->evbit);
1132                 for (i = 0; i < ad714x->hw->button_num; i++) {
1133                         bt_drv[i].input = input;
1134                         __set_bit(bt_plat[i].keycode, input->keybit);
1135                 }
1136
1137                 input->id.bustype = bus_type;
1138                 input->id.product = ad714x->product;
1139                 input->id.version = ad714x->version;
1140                 input->name = "ad714x_captouch_button";
1141                 input->dev.parent = dev;
1142
1143                 error = input_register_device(input);
1144                 if (error)
1145                         return ERR_PTR(error);
1146         }
1147
1148         irqflags = plat_data->irqflags ?: IRQF_TRIGGER_FALLING;
1149         irqflags |= IRQF_ONESHOT;
1150
1151         error = devm_request_threaded_irq(dev, ad714x->irq, NULL,
1152                                           ad714x_interrupt_thread,
1153                                           irqflags, "ad714x_captouch", ad714x);
1154         if (error) {
1155                 dev_err(dev, "can't allocate irq %d\n", ad714x->irq);
1156                 return ERR_PTR(error);
1157         }
1158
1159         return ad714x;
1160 }
1161 EXPORT_SYMBOL(ad714x_probe);
1162
1163 static int ad714x_suspend(struct device *dev)
1164 {
1165         struct ad714x_chip *ad714x = dev_get_drvdata(dev);
1166         unsigned short data;
1167
1168         dev_dbg(ad714x->dev, "%s enter\n", __func__);
1169
1170         guard(mutex)(&ad714x->mutex);
1171
1172         data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3;
1173         ad714x->write(ad714x, AD714X_PWR_CTRL, data);
1174
1175         return 0;
1176 }
1177
1178 static int ad714x_resume(struct device *dev)
1179 {
1180         struct ad714x_chip *ad714x = dev_get_drvdata(dev);
1181         dev_dbg(ad714x->dev, "%s enter\n", __func__);
1182
1183         guard(mutex)(&ad714x->mutex);
1184
1185         /* resume to non-shutdown mode */
1186
1187         ad714x->write(ad714x, AD714X_PWR_CTRL,
1188                         ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]);
1189
1190         /* make sure the interrupt output line is not low level after resume,
1191          * otherwise we will get no chance to enter falling-edge irq again
1192          */
1193
1194         ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3);
1195
1196         return 0;
1197 }
1198
1199 EXPORT_SIMPLE_DEV_PM_OPS(ad714x_pm, ad714x_suspend, ad714x_resume);
1200
1201 MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor Driver");
1202 MODULE_AUTHOR("Barry Song <[email protected]>");
1203 MODULE_LICENSE("GPL");