drivers/hid/hid-multitouch.c

   1 /*
   2  *  HID driver for multitouch panels
   3  *
   4  *  Copyright (c) 2010-2011 Stephane Chatty <chatty@enac.fr>
   5  *  Copyright (c) 2010-2011 Benjamin Tissoires <benjamin.tissoires@gmail.com>
   6  *  Copyright (c) 2010-2011 Ecole Nationale de l'Aviation Civile, France
   7  *
   8  *  This code is partly based on hid-egalax.c:
   9  *
  10  *  Copyright (c) 2010 Stephane Chatty <chatty@enac.fr>
  11  *  Copyright (c) 2010 Henrik Rydberg <rydberg@euromail.se>
  12  *  Copyright (c) 2010 Canonical, Ltd.
  13  *
  14  */
  15
  16 /*
  17  * This program is free software; you can redistribute it and/or modify it
  18  * under the terms of the GNU General Public License as published by the Free
  19  * Software Foundation; either version 2 of the License, or (at your option)
  20  * any later version.
  21  */
  22
  23 #include <linux/device.h>
  24 #include <linux/hid.h>
  25 #include <linux/module.h>
  26 #include <linux/slab.h>
  27 #include <linux/usb.h>
  28 #include <linux/input/mt.h>
  29 #include "usbhid/usbhid.h"
  30
  31
  32 MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
  33 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
  34 MODULE_DESCRIPTION("HID multitouch panels");
  35 MODULE_LICENSE("GPL");
  36
  37 #include "hid-ids.h"
  38
  39 /* quirks to control the device */
  40 #define MT_QUIRK_NOT_SEEN_MEANS_UP      (1 << 0)
  41 #define MT_QUIRK_SLOT_IS_CONTACTID      (1 << 1)
  42 #define MT_QUIRK_CYPRESS                (1 << 2)
  43 #define MT_QUIRK_SLOT_IS_CONTACTNUMBER  (1 << 3)
  44 #define MT_QUIRK_VALID_IS_INRANGE       (1 << 4)
  45 #define MT_QUIRK_VALID_IS_CONFIDENCE    (1 << 5)
  46 #define MT_QUIRK_EGALAX_XYZ_FIXUP       (1 << 6)
  47
  48 struct mt_slot {
  49         __s32 x, y, p, w, h;
  50         __s32 contactid;        /* the device ContactID assigned to this slot */
  51         bool touch_state;       /* is the touch valid? */
  52         bool seen_in_this_frame;/* has this slot been updated */
  53 };
  54
  55 struct mt_device {
  56         struct mt_slot curdata; /* placeholder of incoming data */
  57         struct mt_class *mtclass;       /* our mt device class */
  58         unsigned last_field_index;      /* last field index of the report */
  59         unsigned last_slot_field;       /* the last field of a slot */
  60         __s8 inputmode;         /* InputMode HID feature, -1 if non-existent */
  61         __u8 num_received;      /* how many contacts we received */
  62         __u8 num_expected;      /* expected last contact index */
  63         __u8 maxcontacts;
  64         bool curvalid;          /* is the current contact valid? */
  65         struct mt_slot *slots;
  66 };
  67
  68 struct mt_class {
  69         __s32 name;     /* MT_CLS */
  70         __s32 quirks;
  71         __s32 sn_move;  /* Signal/noise ratio for move events */
  72         __s32 sn_pressure;      /* Signal/noise ratio for pressure events */
  73         __u8 maxcontacts;
  74 };
  75
  76 /* classes of device behavior */
  77 #define MT_CLS_DEFAULT                          1
  78 #define MT_CLS_DUAL_INRANGE_CONTACTID           2
  79 #define MT_CLS_DUAL_INRANGE_CONTACTNUMBER       3
  80 #define MT_CLS_CYPRESS                          4
  81 #define MT_CLS_EGALAX                           5
  82
  83 #define MT_DEFAULT_MAXCONTACT   10
  84
  85 /*
  86  * these device-dependent functions determine what slot corresponds
  87  * to a valid contact that was just read.
  88  */
  89
  90 static int cypress_compute_slot(struct mt_device *td)
  91 {
  92         if (td->curdata.contactid != 0 || td->num_received == 0)
  93                 return td->curdata.contactid;
  94         else
  95                 return -1;
  96 }
  97
  98 static int find_slot_from_contactid(struct mt_device *td)
  99 {
 100         int i;
 101         for (i = 0; i < td->maxcontacts; ++i) {
 102                 if (td->slots[i].contactid == td->curdata.contactid &&
 103                         td->slots[i].touch_state)
 104                         return i;
 105         }
 106         for (i = 0; i < td->maxcontacts; ++i) {
 107                 if (!td->slots[i].seen_in_this_frame &&
 108                         !td->slots[i].touch_state)
 109                         return i;
 110         }
 111         /* should not occurs. If this happens that means
 112          * that the device sent more touches that it says
 113          * in the report descriptor. It is ignored then. */
 114         return -1;
 115 }
 116
 117 struct mt_class mt_classes[] = {
 118         { .name = MT_CLS_DEFAULT,
 119                 .quirks = MT_QUIRK_NOT_SEEN_MEANS_UP },
 120         { .name = MT_CLS_DUAL_INRANGE_CONTACTID,
 121                 .quirks = MT_QUIRK_VALID_IS_INRANGE |
 122                         MT_QUIRK_SLOT_IS_CONTACTID,
 123                 .maxcontacts = 2 },
 124         { .name = MT_CLS_DUAL_INRANGE_CONTACTNUMBER,
 125                 .quirks = MT_QUIRK_VALID_IS_INRANGE |
 126                         MT_QUIRK_SLOT_IS_CONTACTNUMBER,
 127                 .maxcontacts = 2 },
 128         { .name = MT_CLS_CYPRESS,
 129                 .quirks = MT_QUIRK_NOT_SEEN_MEANS_UP |
 130                         MT_QUIRK_CYPRESS,
 131                 .maxcontacts = 10 },
 132
 133         { .name = MT_CLS_EGALAX,
 134                 .quirks =  MT_QUIRK_SLOT_IS_CONTACTID |
 135                         MT_QUIRK_VALID_IS_INRANGE |
 136                         MT_QUIRK_EGALAX_XYZ_FIXUP,
 137                 .maxcontacts = 2,
 138                 .sn_move = 4096,
 139                 .sn_pressure = 32,
 140         },
 141         { }
 142 };
 143
 144 static void mt_feature_mapping(struct hid_device *hdev,
 145                 struct hid_field *field, struct hid_usage *usage)
 146 {
 147         struct mt_device *td = hid_get_drvdata(hdev);
 148
 149         switch (usage->hid) {
 150         case HID_DG_INPUTMODE:
 151                 td->inputmode = field->report->id;
 152                 break;
 153         case HID_DG_CONTACTMAX:
 154                 td->maxcontacts = field->value[0];
 155                 if (td->mtclass->maxcontacts)
 156                         /* check if the maxcontacts is given by the class */
 157                         td->maxcontacts = td->mtclass->maxcontacts;
 158
 159                 break;
 160         }
 161 }
 162
 163 static void set_abs(struct input_dev *input, unsigned int code,
 164                 struct hid_field *field, int snratio)
 165 {
 166         int fmin = field->logical_minimum;
 167         int fmax = field->logical_maximum;
 168         int fuzz = snratio ? (fmax - fmin) / snratio : 0;
 169         input_set_abs_params(input, code, fmin, fmax, fuzz, 0);
 170 }
 171
 172 static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi,
 173                 struct hid_field *field, struct hid_usage *usage,
 174                 unsigned long **bit, int *max)
 175 {
 176         struct mt_device *td = hid_get_drvdata(hdev);
 177         struct mt_class *cls = td->mtclass;
 178         __s32 quirks = cls->quirks;
 179
 180         switch (usage->hid & HID_USAGE_PAGE) {
 181
 182         case HID_UP_GENDESK:
 183                 switch (usage->hid) {
 184                 case HID_GD_X:
 185                         if (quirks & MT_QUIRK_EGALAX_XYZ_FIXUP)
 186                                 field->logical_maximum = 32760;
 187                         hid_map_usage(hi, usage, bit, max,
 188                                         EV_ABS, ABS_MT_POSITION_X);
 189                         set_abs(hi->input, ABS_MT_POSITION_X, field,
 190                                 cls->sn_move);
 191                         /* touchscreen emulation */
 192                         set_abs(hi->input, ABS_X, field, cls->sn_move);
 193                         td->last_slot_field = usage->hid;
 194                         return 1;
 195                 case HID_GD_Y:
 196                         if (quirks & MT_QUIRK_EGALAX_XYZ_FIXUP)
 197                                 field->logical_maximum = 32760;
 198                         hid_map_usage(hi, usage, bit, max,
 199                                         EV_ABS, ABS_MT_POSITION_Y);
 200                         set_abs(hi->input, ABS_MT_POSITION_Y, field,
 201                                 cls->sn_move);
 202                         /* touchscreen emulation */
 203                         set_abs(hi->input, ABS_Y, field, cls->sn_move);
 204                         td->last_slot_field = usage->hid;
 205                         return 1;
 206                 }
 207                 return 0;
 208
 209         case HID_UP_DIGITIZER:
 210                 switch (usage->hid) {
 211                 case HID_DG_INRANGE:
 212                         td->last_slot_field = usage->hid;
 213                         return 1;
 214                 case HID_DG_CONFIDENCE:
 215                         td->last_slot_field = usage->hid;
 216                         return 1;
 217                 case HID_DG_TIPSWITCH:
 218                         hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH);
 219                         input_set_capability(hi->input, EV_KEY, BTN_TOUCH);
 220                         td->last_slot_field = usage->hid;
 221                         return 1;
 222                 case HID_DG_CONTACTID:
 223                         input_mt_init_slots(hi->input, td->maxcontacts);
 224                         td->last_slot_field = usage->hid;
 225                         return 1;
 226                 case HID_DG_WIDTH:
 227                         hid_map_usage(hi, usage, bit, max,
 228                                         EV_ABS, ABS_MT_TOUCH_MAJOR);
 229                         td->last_slot_field = usage->hid;
 230                         return 1;
 231                 case HID_DG_HEIGHT:
 232                         hid_map_usage(hi, usage, bit, max,
 233                                         EV_ABS, ABS_MT_TOUCH_MINOR);
 234                         field->logical_maximum = 1;
 235                         field->logical_minimum = 0;
 236                         set_abs(hi->input, ABS_MT_ORIENTATION, field, 0);
 237                         td->last_slot_field = usage->hid;
 238                         return 1;
 239                 case HID_DG_TIPPRESSURE:
 240                         if (quirks & MT_QUIRK_EGALAX_XYZ_FIXUP)
 241                                 field->logical_minimum = 0;
 242                         hid_map_usage(hi, usage, bit, max,
 243                                         EV_ABS, ABS_MT_PRESSURE);
 244                         set_abs(hi->input, ABS_MT_PRESSURE, field,
 245                                 cls->sn_pressure);
 246                         /* touchscreen emulation */
 247                         set_abs(hi->input, ABS_PRESSURE, field,
 248                                 cls->sn_pressure);
 249                         td->last_slot_field = usage->hid;
 250                         return 1;
 251                 case HID_DG_CONTACTCOUNT:
 252                         td->last_field_index = field->report->maxfield - 1;
 253                         return 1;
 254                 case HID_DG_CONTACTMAX:
 255                         /* we don't set td->last_slot_field as contactcount and
 256                          * contact max are global to the report */
 257                         return -1;
 258                 }
 259                 /* let hid-input decide for the others */
 260                 return 0;
 261
 262         case 0xff000000:
 263                 /* we do not want to map these: no input-oriented meaning */
 264                 return -1;
 265         }
 266
 267         return 0;
 268 }
 269
 270 static int mt_input_mapped(struct hid_device *hdev, struct hid_input *hi,
 271                 struct hid_field *field, struct hid_usage *usage,
 272                 unsigned long **bit, int *max)
 273 {
 274         if (usage->type == EV_KEY || usage->type == EV_ABS)
 275                 set_bit(usage->type, hi->input->evbit);
 276
 277         return -1;
 278 }
 279
 280 static int mt_compute_slot(struct mt_device *td)
 281 {
 282         __s32 quirks = td->mtclass->quirks;
 283
 284         if (quirks & MT_QUIRK_SLOT_IS_CONTACTID)
 285                 return td->curdata.contactid;
 286
 287         if (quirks & MT_QUIRK_CYPRESS)
 288                 return cypress_compute_slot(td);
 289
 290         if (quirks & MT_QUIRK_SLOT_IS_CONTACTNUMBER)
 291                 return td->num_received;
 292
 293         return find_slot_from_contactid(td);
 294 }
 295
 296 /*
 297  * this function is called when a whole contact has been processed,
 298  * so that it can assign it to a slot and store the data there
 299  */
 300 static void mt_complete_slot(struct mt_device *td)
 301 {
 302         td->curdata.seen_in_this_frame = true;
 303         if (td->curvalid) {
 304                 int slotnum = mt_compute_slot(td);
 305
 306                 if (slotnum >= 0 && slotnum < td->maxcontacts)
 307                         td->slots[slotnum] = td->curdata;
 308         }
 309         td->num_received++;
 310 }
 311
 312
 313 /*
 314  * this function is called when a whole packet has been received and processed,
 315  * so that it can decide what to send to the input layer.
 316  */
 317 static void mt_emit_event(struct mt_device *td, struct input_dev *input)
 318 {
 319         int i;
 320
 321         for (i = 0; i < td->maxcontacts; ++i) {
 322                 struct mt_slot *s = &(td->slots[i]);
 323                 if ((td->mtclass->quirks & MT_QUIRK_NOT_SEEN_MEANS_UP) &&
 324                         !s->seen_in_this_frame) {
 325                         s->touch_state = false;
 326                 }
 327
 328                 input_mt_slot(input, i);
 329                 input_mt_report_slot_state(input, MT_TOOL_FINGER,
 330                         s->touch_state);
 331                 if (s->touch_state) {
 332                         input_event(input, EV_ABS, ABS_MT_POSITION_X, s->x);
 333                         input_event(input, EV_ABS, ABS_MT_POSITION_Y, s->y);
 334                         input_event(input, EV_ABS, ABS_MT_PRESSURE, s->p);
 335                         input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, s->w);
 336                         input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, s->h);
 337                 }
 338                 s->seen_in_this_frame = false;
 339
 340         }
 341
 342         input_mt_report_pointer_emulation(input, true);
 343         input_sync(input);
 344         td->num_received = 0;
 345 }
 346
 347
 348
 349 static int mt_event(struct hid_device *hid, struct hid_field *field,
 350                                 struct hid_usage *usage, __s32 value)
 351 {
 352         struct mt_device *td = hid_get_drvdata(hid);
 353         __s32 quirks = td->mtclass->quirks;
 354
 355         if (hid->claimed & HID_CLAIMED_INPUT && td->slots) {
 356                 switch (usage->hid) {
 357                 case HID_DG_INRANGE:
 358                         if (quirks & MT_QUIRK_VALID_IS_INRANGE)
 359                                 td->curvalid = value;
 360                         break;
 361                 case HID_DG_TIPSWITCH:
 362                         if (quirks & MT_QUIRK_NOT_SEEN_MEANS_UP)
 363                                 td->curvalid = value;
 364                         td->curdata.touch_state = value;
 365                         break;
 366                 case HID_DG_CONFIDENCE:
 367                         if (quirks & MT_QUIRK_VALID_IS_CONFIDENCE)
 368                                 td->curvalid = value;
 369                         break;
 370                 case HID_DG_CONTACTID:
 371                         td->curdata.contactid = value;
 372                         break;
 373                 case HID_DG_TIPPRESSURE:
 374                         td->curdata.p = value;
 375                         break;
 376                 case HID_GD_X:
 377                         td->curdata.x = value;
 378                         break;
 379                 case HID_GD_Y:
 380                         td->curdata.y = value;
 381                         break;
 382                 case HID_DG_WIDTH:
 383                         td->curdata.w = value;
 384                         break;
 385                 case HID_DG_HEIGHT:
 386                         td->curdata.h = value;
 387                         break;
 388                 case HID_DG_CONTACTCOUNT:
 389                         /*
 390                          * Includes multi-packet support where subsequent
 391                          * packets are sent with zero contactcount.
 392                          */
 393                         if (value)
 394                                 td->num_expected = value;
 395                         break;
 396
 397                 default:
 398                         /* fallback to the generic hidinput handling */
 399                         return 0;
 400                 }
 401
 402                 if (usage->hid == td->last_slot_field) {
 403                         mt_complete_slot(td);
 404                         if (!td->last_field_index)
 405                                 mt_emit_event(td, field->hidinput->input);
 406                 }
 407
 408                 if (field->index == td->last_field_index
 409                         && td->num_received >= td->num_expected)
 410                         mt_emit_event(td, field->hidinput->input);
 411
 412         }
 413
 414         /* we have handled the hidinput part, now remains hiddev */
 415         if (hid->claimed & HID_CLAIMED_HIDDEV && hid->hiddev_hid_event)
 416                 hid->hiddev_hid_event(hid, field, usage, value);
 417
 418         return 1;
 419 }
 420
 421 static void mt_set_input_mode(struct hid_device *hdev)
 422 {
 423         struct mt_device *td = hid_get_drvdata(hdev);
 424         struct hid_report *r;
 425         struct hid_report_enum *re;
 426
 427         if (td->inputmode < 0)
 428                 return;
 429
 430         re = &(hdev->report_enum[HID_FEATURE_REPORT]);
 431         r = re->report_id_hash[td->inputmode];
 432         if (r) {
 433                 r->field[0]->value[0] = 0x02;
 434                 usbhid_submit_report(hdev, r, USB_DIR_OUT);
 435         }
 436 }
 437
 438 static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
 439 {
 440         int ret, i;
 441         struct mt_device *td;
 442         struct mt_class *mtclass = mt_classes; /* MT_CLS_DEFAULT */
 443
 444         for (i = 0; mt_classes[i].name ; i++) {
 445                 if (id->driver_data == mt_classes[i].name) {
 446                         mtclass = &(mt_classes[i]);
 447                         break;
 448                 }
 449         }
 450
 451         /* This allows the driver to correctly support devices
 452          * that emit events over several HID messages.
 453          */
 454         hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC;
 455
 456         td = kzalloc(sizeof(struct mt_device), GFP_KERNEL);
 457         if (!td) {
 458                 dev_err(&hdev->dev, "cannot allocate multitouch data\n");
 459                 return -ENOMEM;
 460         }
 461         td->mtclass = mtclass;
 462         td->inputmode = -1;
 463         hid_set_drvdata(hdev, td);
 464
 465         ret = hid_parse(hdev);
 466         if (ret != 0)
 467                 goto fail;
 468
 469         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 470         if (ret)
 471                 goto fail;
 472
 473         if (!td->maxcontacts)
 474                 td->maxcontacts = MT_DEFAULT_MAXCONTACT;
 475
 476         td->slots = kzalloc(td->maxcontacts * sizeof(struct mt_slot),
 477                                 GFP_KERNEL);
 478         if (!td->slots) {
 479                 dev_err(&hdev->dev, "cannot allocate multitouch slots\n");
 480                 hid_hw_stop(hdev);
 481                 ret = -ENOMEM;
 482                 goto fail;
 483         }
 484
 485         mt_set_input_mode(hdev);
 486
 487         return 0;
 488
 489 fail:
 490         kfree(td);
 491         return ret;
 492 }
 493
 494 #ifdef CONFIG_PM
 495 static int mt_reset_resume(struct hid_device *hdev)
 496 {
 497         mt_set_input_mode(hdev);
 498         return 0;
 499 }
 500 #endif
 501
 502 static void mt_remove(struct hid_device *hdev)
 503 {
 504         struct mt_device *td = hid_get_drvdata(hdev);
 505         hid_hw_stop(hdev);
 506         kfree(td->slots);
 507         kfree(td);
 508         hid_set_drvdata(hdev, NULL);
 509 }
 510
 511 static const struct hid_device_id mt_devices[] = {
 512
 513         /* Cypress panel */
 514         { .driver_data = MT_CLS_CYPRESS,
 515                 HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS,
 516                         USB_DEVICE_ID_CYPRESS_TRUETOUCH) },
 517
 518         /* GeneralTouch panel */
 519         { .driver_data = MT_CLS_DUAL_INRANGE_CONTACTNUMBER,
 520                 HID_USB_DEVICE(USB_VENDOR_ID_GENERAL_TOUCH,
 521                         USB_DEVICE_ID_GENERAL_TOUCH_WIN7_TWOFINGERS) },
 522
 523         /* IRTOUCH panels */
 524         { .driver_data = MT_CLS_DUAL_INRANGE_CONTACTID,
 525                 HID_USB_DEVICE(USB_VENDOR_ID_IRTOUCHSYSTEMS,
 526                         USB_DEVICE_ID_IRTOUCH_INFRARED_USB) },
 527
 528         /* PixCir-based panels */
 529         { .driver_data = MT_CLS_DUAL_INRANGE_CONTACTID,
 530                 HID_USB_DEVICE(USB_VENDOR_ID_HANVON,
 531                         USB_DEVICE_ID_HANVON_MULTITOUCH) },
 532         { .driver_data = MT_CLS_DUAL_INRANGE_CONTACTID,
 533                 HID_USB_DEVICE(USB_VENDOR_ID_CANDO,
 534                         USB_DEVICE_ID_CANDO_PIXCIR_MULTI_TOUCH) },
 535
 536         /* Resistive eGalax devices */
 537         {  .driver_data = MT_CLS_EGALAX,
 538                 HID_USB_DEVICE(USB_VENDOR_ID_DWAV,
 539                         USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH) },
 540         {  .driver_data = MT_CLS_EGALAX,
 541                 HID_USB_DEVICE(USB_VENDOR_ID_DWAV,
 542                         USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH3) },
 543
 544         /* Capacitive eGalax devices */
 545         {  .driver_data = MT_CLS_EGALAX,
 546                 HID_USB_DEVICE(USB_VENDOR_ID_DWAV,
 547                         USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH1) },
 548         {  .driver_data = MT_CLS_EGALAX,
 549                 HID_USB_DEVICE(USB_VENDOR_ID_DWAV,
 550                         USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH2) },
 551         {  .driver_data = MT_CLS_EGALAX,
 552                 HID_USB_DEVICE(USB_VENDOR_ID_DWAV,
 553                         USB_DEVICE_ID_DWAV_EGALAX_MULTITOUCH4) },
 554
 555         { }
 556 };
 557 MODULE_DEVICE_TABLE(hid, mt_devices);
 558
 559 static const struct hid_usage_id mt_grabbed_usages[] = {
 560         { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
 561         { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
 562 };
 563
 564 static struct hid_driver mt_driver = {
 565         .name = "hid-multitouch",
 566         .id_table = mt_devices,
 567         .probe = mt_probe,
 568         .remove = mt_remove,
 569         .input_mapping = mt_input_mapping,
 570         .input_mapped = mt_input_mapped,
 571         .feature_mapping = mt_feature_mapping,
 572         .usage_table = mt_grabbed_usages,
 573         .event = mt_event,
 574 #ifdef CONFIG_PM
 575         .reset_resume = mt_reset_resume,
 576 #endif
 577 };
 578
 579 static int __init mt_init(void)
 580 {
 581         return hid_register_driver(&mt_driver);
 582 }
 583
 584 static void __exit mt_exit(void)
 585 {
 586         hid_unregister_driver(&mt_driver);
 587 }
 588
 589 module_init(mt_init);
 590 module_exit(mt_exit);