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