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 */ 9 10 /* 11 * This program is free software; you can redistribute it and/or modify it 12 * under the terms of the GNU General Public License as published by the Free 13 * Software Foundation; either version 2 of the License, or (at your option) 14 * any later version. 15 */ 16 17 #include <linux/device.h> 18 #include <linux/hid.h> 19 #include <linux/module.h> 20 #include <linux/slab.h> 21 #include <linux/usb.h> 22 #include <linux/input/mt.h> 23 #include "usbhid/usbhid.h" 24 25 26 MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>"); 27 MODULE_DESCRIPTION("HID multitouch panels"); 28 MODULE_LICENSE("GPL"); 29 30 #include "hid-ids.h" 31 32 /* quirks to control the device */ 33 #define MT_QUIRK_NOT_SEEN_MEANS_UP (1 << 0) 34 #define MT_QUIRK_SLOT_IS_CONTACTID (1 << 1) 35 #define MT_QUIRK_CYPRESS (1 << 2) 36 #define MT_QUIRK_SLOT_IS_CONTACTNUMBER (1 << 3) 37 #define MT_QUIRK_VALID_IS_INRANGE (1 << 4) 38 #define MT_QUIRK_VALID_IS_CONFIDENCE (1 << 5) 39 40 struct mt_slot { 41 __s32 x, y, p, w, h; 42 __s32 contactid; /* the device ContactID assigned to this slot */ 43 bool touch_state; /* is the touch valid? */ 44 bool seen_in_this_frame;/* has this slot been updated */ 45 }; 46 47 struct mt_device { 48 struct mt_slot curdata; /* placeholder of incoming data */ 49 struct mt_class *mtclass; /* our mt device class */ 50 unsigned last_field_index; /* last field index of the report */ 51 unsigned last_slot_field; /* the last field of a slot */ 52 __s8 inputmode; /* InputMode HID feature, -1 if non-existent */ 53 __u8 num_received; /* how many contacts we received */ 54 __u8 num_expected; /* expected last contact index */ 55 bool curvalid; /* is the current contact valid? */ 56 struct mt_slot slots[0]; /* first slot */ 57 }; 58 59 struct mt_class { 60 __s32 name; /* MT_CLS */ 61 __s32 quirks; 62 __s32 sn_move; /* Signal/noise ratio for move events */ 63 __s32 sn_pressure; /* Signal/noise ratio for pressure events */ 64 __u8 maxcontacts; 65 }; 66 67 /* classes of device behavior */ 68 #define MT_CLS_DEFAULT 1 69 #define MT_CLS_DUAL1 2 70 #define MT_CLS_DUAL2 3 71 #define MT_CLS_CYPRESS 4 72 73 /* 74 * these device-dependent functions determine what slot corresponds 75 * to a valid contact that was just read. 76 */ 77 78 static int cypress_compute_slot(struct mt_device *td) 79 { 80 if (td->curdata.contactid != 0 || td->num_received == 0) 81 return td->curdata.contactid; 82 else 83 return -1; 84 } 85 86 static int find_slot_from_contactid(struct mt_device *td) 87 { 88 int i; 89 for (i = 0; i < td->mtclass->maxcontacts; ++i) { 90 if (td->slots[i].contactid == td->curdata.contactid && 91 td->slots[i].touch_state) 92 return i; 93 } 94 for (i = 0; i < td->mtclass->maxcontacts; ++i) { 95 if (!td->slots[i].seen_in_this_frame && 96 !td->slots[i].touch_state) 97 return i; 98 } 99 /* should not occurs. If this happens that means 100 * that the device sent more touches that it says 101 * in the report descriptor. It is ignored then. */ 102 return -1; 103 } 104 105 struct mt_class mt_classes[] = { 106 { .name = MT_CLS_DEFAULT, 107 .quirks = MT_QUIRK_VALID_IS_INRANGE, 108 .maxcontacts = 10 }, 109 { .name = MT_CLS_DUAL1, 110 .quirks = MT_QUIRK_VALID_IS_INRANGE | 111 MT_QUIRK_SLOT_IS_CONTACTID, 112 .maxcontacts = 2 }, 113 { .name = MT_CLS_DUAL2, 114 .quirks = MT_QUIRK_VALID_IS_INRANGE | 115 MT_QUIRK_SLOT_IS_CONTACTNUMBER, 116 .maxcontacts = 2 }, 117 { .name = MT_CLS_CYPRESS, 118 .quirks = MT_QUIRK_NOT_SEEN_MEANS_UP | 119 MT_QUIRK_CYPRESS, 120 .maxcontacts = 10 }, 121 122 { } 123 }; 124 125 static void mt_feature_mapping(struct hid_device *hdev, struct hid_input *hi, 126 struct hid_field *field, struct hid_usage *usage) 127 { 128 if (usage->hid == HID_DG_INPUTMODE) { 129 struct mt_device *td = hid_get_drvdata(hdev); 130 td->inputmode = field->report->id; 131 } 132 } 133 134 static void set_abs(struct input_dev *input, unsigned int code, 135 struct hid_field *field, int snratio) 136 { 137 int fmin = field->logical_minimum; 138 int fmax = field->logical_maximum; 139 int fuzz = snratio ? (fmax - fmin) / snratio : 0; 140 input_set_abs_params(input, code, fmin, fmax, fuzz, 0); 141 } 142 143 static int mt_input_mapping(struct hid_device *hdev, struct hid_input *hi, 144 struct hid_field *field, struct hid_usage *usage, 145 unsigned long **bit, int *max) 146 { 147 struct mt_device *td = hid_get_drvdata(hdev); 148 struct mt_class *cls = td->mtclass; 149 switch (usage->hid & HID_USAGE_PAGE) { 150 151 case HID_UP_GENDESK: 152 switch (usage->hid) { 153 case HID_GD_X: 154 hid_map_usage(hi, usage, bit, max, 155 EV_ABS, ABS_MT_POSITION_X); 156 set_abs(hi->input, ABS_MT_POSITION_X, field, 157 cls->sn_move); 158 /* touchscreen emulation */ 159 set_abs(hi->input, ABS_X, field, cls->sn_move); 160 td->last_slot_field = usage->hid; 161 return 1; 162 case HID_GD_Y: 163 hid_map_usage(hi, usage, bit, max, 164 EV_ABS, ABS_MT_POSITION_Y); 165 set_abs(hi->input, ABS_MT_POSITION_Y, field, 166 cls->sn_move); 167 /* touchscreen emulation */ 168 set_abs(hi->input, ABS_Y, field, cls->sn_move); 169 td->last_slot_field = usage->hid; 170 return 1; 171 } 172 return 0; 173 174 case HID_UP_DIGITIZER: 175 switch (usage->hid) { 176 case HID_DG_INRANGE: 177 td->last_slot_field = usage->hid; 178 return 1; 179 case HID_DG_CONFIDENCE: 180 td->last_slot_field = usage->hid; 181 return 1; 182 case HID_DG_TIPSWITCH: 183 hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH); 184 input_set_capability(hi->input, EV_KEY, BTN_TOUCH); 185 td->last_slot_field = usage->hid; 186 return 1; 187 case HID_DG_CONTACTID: 188 input_mt_init_slots(hi->input, 189 td->mtclass->maxcontacts); 190 td->last_slot_field = usage->hid; 191 return 1; 192 case HID_DG_WIDTH: 193 hid_map_usage(hi, usage, bit, max, 194 EV_ABS, ABS_MT_TOUCH_MAJOR); 195 td->last_slot_field = usage->hid; 196 return 1; 197 case HID_DG_HEIGHT: 198 hid_map_usage(hi, usage, bit, max, 199 EV_ABS, ABS_MT_TOUCH_MINOR); 200 field->logical_maximum = 1; 201 field->logical_minimum = 0; 202 set_abs(hi->input, ABS_MT_ORIENTATION, field, 0); 203 td->last_slot_field = usage->hid; 204 return 1; 205 case HID_DG_TIPPRESSURE: 206 hid_map_usage(hi, usage, bit, max, 207 EV_ABS, ABS_MT_PRESSURE); 208 set_abs(hi->input, ABS_MT_PRESSURE, field, 209 cls->sn_pressure); 210 /* touchscreen emulation */ 211 set_abs(hi->input, ABS_PRESSURE, field, 212 cls->sn_pressure); 213 td->last_slot_field = usage->hid; 214 return 1; 215 case HID_DG_CONTACTCOUNT: 216 td->last_field_index = field->report->maxfield - 1; 217 return 1; 218 case HID_DG_CONTACTMAX: 219 /* we don't set td->last_slot_field as contactcount and 220 * contact max are global to the report */ 221 return -1; 222 } 223 /* let hid-input decide for the others */ 224 return 0; 225 226 case 0xff000000: 227 /* we do not want to map these: no input-oriented meaning */ 228 return -1; 229 } 230 231 return 0; 232 } 233 234 static int mt_input_mapped(struct hid_device *hdev, struct hid_input *hi, 235 struct hid_field *field, struct hid_usage *usage, 236 unsigned long **bit, int *max) 237 { 238 if (usage->type == EV_KEY || usage->type == EV_ABS) 239 set_bit(usage->type, hi->input->evbit); 240 241 return -1; 242 } 243 244 static int mt_compute_slot(struct mt_device *td) 245 { 246 __s32 quirks = td->mtclass->quirks; 247 248 if (quirks & MT_QUIRK_SLOT_IS_CONTACTID) 249 return td->curdata.contactid; 250 251 if (quirks & MT_QUIRK_CYPRESS) 252 return cypress_compute_slot(td); 253 254 if (quirks & MT_QUIRK_SLOT_IS_CONTACTNUMBER) 255 return td->num_received; 256 257 return find_slot_from_contactid(td); 258 } 259 260 /* 261 * this function is called when a whole contact has been processed, 262 * so that it can assign it to a slot and store the data there 263 */ 264 static void mt_complete_slot(struct mt_device *td) 265 { 266 td->curdata.seen_in_this_frame = true; 267 if (td->curvalid) { 268 int slotnum = mt_compute_slot(td); 269 270 if (slotnum >= 0 && slotnum < td->mtclass->maxcontacts) 271 td->slots[slotnum] = td->curdata; 272 } 273 td->num_received++; 274 } 275 276 277 /* 278 * this function is called when a whole packet has been received and processed, 279 * so that it can decide what to send to the input layer. 280 */ 281 static void mt_emit_event(struct mt_device *td, struct input_dev *input) 282 { 283 int i; 284 285 for (i = 0; i < td->mtclass->maxcontacts; ++i) { 286 struct mt_slot *s = &(td->slots[i]); 287 if ((td->mtclass->quirks & MT_QUIRK_NOT_SEEN_MEANS_UP) && 288 !s->seen_in_this_frame) { 289 s->touch_state = false; 290 } 291 292 input_mt_slot(input, i); 293 input_mt_report_slot_state(input, MT_TOOL_FINGER, 294 s->touch_state); 295 if (s->touch_state) { 296 input_event(input, EV_ABS, ABS_MT_POSITION_X, s->x); 297 input_event(input, EV_ABS, ABS_MT_POSITION_Y, s->y); 298 input_event(input, EV_ABS, ABS_MT_PRESSURE, s->p); 299 input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, s->w); 300 input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, s->h); 301 } 302 s->seen_in_this_frame = false; 303 304 } 305 306 input_mt_report_pointer_emulation(input, true); 307 input_sync(input); 308 td->num_received = 0; 309 } 310 311 312 313 static int mt_event(struct hid_device *hid, struct hid_field *field, 314 struct hid_usage *usage, __s32 value) 315 { 316 struct mt_device *td = hid_get_drvdata(hid); 317 __s32 quirks = td->mtclass->quirks; 318 319 if (hid->claimed & HID_CLAIMED_INPUT) { 320 switch (usage->hid) { 321 case HID_DG_INRANGE: 322 if (quirks & MT_QUIRK_VALID_IS_INRANGE) 323 td->curvalid = value; 324 break; 325 case HID_DG_TIPSWITCH: 326 if (quirks & MT_QUIRK_NOT_SEEN_MEANS_UP) 327 td->curvalid = value; 328 td->curdata.touch_state = value; 329 break; 330 case HID_DG_CONFIDENCE: 331 if (quirks & MT_QUIRK_VALID_IS_CONFIDENCE) 332 td->curvalid = value; 333 break; 334 case HID_DG_CONTACTID: 335 td->curdata.contactid = value; 336 break; 337 case HID_DG_TIPPRESSURE: 338 td->curdata.p = value; 339 break; 340 case HID_GD_X: 341 td->curdata.x = value; 342 break; 343 case HID_GD_Y: 344 td->curdata.y = value; 345 break; 346 case HID_DG_WIDTH: 347 td->curdata.w = value; 348 break; 349 case HID_DG_HEIGHT: 350 td->curdata.h = value; 351 break; 352 case HID_DG_CONTACTCOUNT: 353 /* 354 * Includes multi-packet support where subsequent 355 * packets are sent with zero contactcount. 356 */ 357 if (value) 358 td->num_expected = value; 359 break; 360 361 default: 362 /* fallback to the generic hidinput handling */ 363 return 0; 364 } 365 366 if (usage->hid == td->last_slot_field) 367 mt_complete_slot(td); 368 369 if (field->index == td->last_field_index 370 && td->num_received >= td->num_expected) 371 mt_emit_event(td, field->hidinput->input); 372 373 } 374 375 /* we have handled the hidinput part, now remains hiddev */ 376 if (hid->claimed & HID_CLAIMED_HIDDEV && hid->hiddev_hid_event) 377 hid->hiddev_hid_event(hid, field, usage, value); 378 379 return 1; 380 } 381 382 static void mt_set_input_mode(struct hid_device *hdev) 383 { 384 struct mt_device *td = hid_get_drvdata(hdev); 385 struct hid_report *r; 386 struct hid_report_enum *re; 387 388 if (td->inputmode < 0) 389 return; 390 391 re = &(hdev->report_enum[HID_FEATURE_REPORT]); 392 r = re->report_id_hash[td->inputmode]; 393 if (r) { 394 r->field[0]->value[0] = 0x02; 395 usbhid_submit_report(hdev, r, USB_DIR_OUT); 396 } 397 } 398 399 static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id) 400 { 401 int ret, i; 402 struct mt_device *td; 403 struct mt_class *mtclass = mt_classes; /* MT_CLS_DEFAULT */ 404 405 for (i = 0; mt_classes[i].name ; i++) { 406 if (id->driver_data == mt_classes[i].name) { 407 mtclass = &(mt_classes[i]); 408 break; 409 } 410 } 411 412 /* This allows the driver to correctly support devices 413 * that emit events over several HID messages. 414 */ 415 hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC; 416 417 td = kzalloc(sizeof(struct mt_device) + 418 mtclass->maxcontacts * sizeof(struct mt_slot), 419 GFP_KERNEL); 420 if (!td) { 421 dev_err(&hdev->dev, "cannot allocate multitouch data\n"); 422 return -ENOMEM; 423 } 424 td->mtclass = mtclass; 425 td->inputmode = -1; 426 hid_set_drvdata(hdev, td); 427 428 ret = hid_parse(hdev); 429 if (ret != 0) 430 goto fail; 431 432 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); 433 if (ret) 434 goto fail; 435 436 mt_set_input_mode(hdev); 437 438 return 0; 439 440 fail: 441 kfree(td); 442 return ret; 443 } 444 445 #ifdef CONFIG_PM 446 static int mt_reset_resume(struct hid_device *hdev) 447 { 448 mt_set_input_mode(hdev); 449 return 0; 450 } 451 #endif 452 453 static void mt_remove(struct hid_device *hdev) 454 { 455 struct mt_device *td = hid_get_drvdata(hdev); 456 hid_hw_stop(hdev); 457 kfree(td); 458 hid_set_drvdata(hdev, NULL); 459 } 460 461 static const struct hid_device_id mt_devices[] = { 462 463 /* Cypress panel */ 464 { .driver_data = MT_CLS_CYPRESS, 465 HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, 466 USB_DEVICE_ID_CYPRESS_TRUETOUCH) }, 467 468 /* GeneralTouch panel */ 469 { .driver_data = MT_CLS_DUAL2, 470 HID_USB_DEVICE(USB_VENDOR_ID_GENERAL_TOUCH, 471 USB_DEVICE_ID_GENERAL_TOUCH_WIN7_TWOFINGERS) }, 472 473 /* PixCir-based panels */ 474 { .driver_data = MT_CLS_DUAL1, 475 HID_USB_DEVICE(USB_VENDOR_ID_HANVON, 476 USB_DEVICE_ID_HANVON_MULTITOUCH) }, 477 { .driver_data = MT_CLS_DUAL1, 478 HID_USB_DEVICE(USB_VENDOR_ID_CANDO, 479 USB_DEVICE_ID_CANDO_PIXCIR_MULTI_TOUCH) }, 480 481 { } 482 }; 483 MODULE_DEVICE_TABLE(hid, mt_devices); 484 485 static const struct hid_usage_id mt_grabbed_usages[] = { 486 { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID }, 487 { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1} 488 }; 489 490 static struct hid_driver mt_driver = { 491 .name = "hid-multitouch", 492 .id_table = mt_devices, 493 .probe = mt_probe, 494 .remove = mt_remove, 495 .input_mapping = mt_input_mapping, 496 .input_mapped = mt_input_mapped, 497 .feature_mapping = mt_feature_mapping, 498 .usage_table = mt_grabbed_usages, 499 .event = mt_event, 500 #ifdef CONFIG_PM 501 .reset_resume = mt_reset_resume, 502 #endif 503 }; 504 505 static int __init mt_init(void) 506 { 507 return hid_register_driver(&mt_driver); 508 } 509 510 static void __exit mt_exit(void) 511 { 512 hid_unregister_driver(&mt_driver); 513 } 514 515 module_init(mt_init); 516 module_exit(mt_exit); 517