1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * HID driver for N-Trig touchscreens 4 * 5 * Copyright (c) 2008-2010 Rafi Rubin 6 * Copyright (c) 2009-2010 Stephane Chatty 7 */ 8 9 /* 10 */ 11 12 #include <linux/device.h> 13 #include <linux/hid.h> 14 #include <linux/usb.h> 15 #include "usbhid/usbhid.h" 16 #include <linux/module.h> 17 #include <linux/slab.h> 18 19 #include "hid-ids.h" 20 21 #define NTRIG_DUPLICATE_USAGES 0x001 22 23 static unsigned int min_width; 24 module_param(min_width, uint, 0644); 25 MODULE_PARM_DESC(min_width, "Minimum touch contact width to accept."); 26 27 static unsigned int min_height; 28 module_param(min_height, uint, 0644); 29 MODULE_PARM_DESC(min_height, "Minimum touch contact height to accept."); 30 31 static unsigned int activate_slack = 1; 32 module_param(activate_slack, uint, 0644); 33 MODULE_PARM_DESC(activate_slack, "Number of touch frames to ignore at " 34 "the start of touch input."); 35 36 static unsigned int deactivate_slack = 4; 37 module_param(deactivate_slack, uint, 0644); 38 MODULE_PARM_DESC(deactivate_slack, "Number of empty frames to ignore before " 39 "deactivating touch."); 40 41 static unsigned int activation_width = 64; 42 module_param(activation_width, uint, 0644); 43 MODULE_PARM_DESC(activation_width, "Width threshold to immediately start " 44 "processing touch events."); 45 46 static unsigned int activation_height = 32; 47 module_param(activation_height, uint, 0644); 48 MODULE_PARM_DESC(activation_height, "Height threshold to immediately start " 49 "processing touch events."); 50 51 struct ntrig_data { 52 /* Incoming raw values for a single contact */ 53 __u16 x, y, w, h; 54 __u16 id; 55 56 bool tipswitch; 57 bool confidence; 58 bool first_contact_touch; 59 60 bool reading_mt; 61 62 __u8 mt_footer[4]; 63 __u8 mt_foot_count; 64 65 /* The current activation state. */ 66 __s8 act_state; 67 68 /* Empty frames to ignore before recognizing the end of activity */ 69 __s8 deactivate_slack; 70 71 /* Frames to ignore before acknowledging the start of activity */ 72 __s8 activate_slack; 73 74 /* Minimum size contact to accept */ 75 __u16 min_width; 76 __u16 min_height; 77 78 /* Threshold to override activation slack */ 79 __u16 activation_width; 80 __u16 activation_height; 81 82 __u16 sensor_logical_width; 83 __u16 sensor_logical_height; 84 __u16 sensor_physical_width; 85 __u16 sensor_physical_height; 86 }; 87 88 89 /* 90 * This function converts the 4 byte raw firmware code into 91 * a string containing 5 comma separated numbers. 92 */ 93 static int ntrig_version_string(unsigned char *raw, char *buf) 94 { 95 __u8 a = (raw[1] & 0x0e) >> 1; 96 __u8 b = (raw[0] & 0x3c) >> 2; 97 __u8 c = ((raw[0] & 0x03) << 3) | ((raw[3] & 0xe0) >> 5); 98 __u8 d = ((raw[3] & 0x07) << 3) | ((raw[2] & 0xe0) >> 5); 99 __u8 e = raw[2] & 0x07; 100 101 /* 102 * As yet unmapped bits: 103 * 0b11000000 0b11110001 0b00011000 0b00011000 104 */ 105 106 return sprintf(buf, "%u.%u.%u.%u.%u", a, b, c, d, e); 107 } 108 109 static inline int ntrig_get_mode(struct hid_device *hdev) 110 { 111 struct hid_report *report = hdev->report_enum[HID_FEATURE_REPORT]. 112 report_id_hash[0x0d]; 113 114 if (!report || report->maxfield < 1 || 115 report->field[0]->report_count < 1) 116 return -EINVAL; 117 118 hid_hw_request(hdev, report, HID_REQ_GET_REPORT); 119 hid_hw_wait(hdev); 120 return (int)report->field[0]->value[0]; 121 } 122 123 static inline void ntrig_set_mode(struct hid_device *hdev, const int mode) 124 { 125 struct hid_report *report; 126 __u8 mode_commands[4] = { 0xe, 0xf, 0x1b, 0x10 }; 127 128 if (mode < 0 || mode > 3) 129 return; 130 131 report = hdev->report_enum[HID_FEATURE_REPORT]. 132 report_id_hash[mode_commands[mode]]; 133 134 if (!report) 135 return; 136 137 hid_hw_request(hdev, report, HID_REQ_GET_REPORT); 138 } 139 140 static void ntrig_report_version(struct hid_device *hdev) 141 { 142 int ret; 143 char buf[20]; 144 struct usb_device *usb_dev = hid_to_usb_dev(hdev); 145 unsigned char *data = kmalloc(8, GFP_KERNEL); 146 147 if (!data) 148 goto err_free; 149 150 ret = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0), 151 USB_REQ_CLEAR_FEATURE, 152 USB_TYPE_CLASS | USB_RECIP_INTERFACE | 153 USB_DIR_IN, 154 0x30c, 1, data, 8, 155 USB_CTRL_SET_TIMEOUT); 156 157 if (ret == 8) { 158 ret = ntrig_version_string(&data[2], buf); 159 160 hid_info(hdev, "Firmware version: %s (%02x%02x %02x%02x)\n", 161 buf, data[2], data[3], data[4], data[5]); 162 } 163 164 err_free: 165 kfree(data); 166 } 167 168 static ssize_t show_phys_width(struct device *dev, 169 struct device_attribute *attr, 170 char *buf) 171 { 172 struct hid_device *hdev = to_hid_device(dev); 173 struct ntrig_data *nd = hid_get_drvdata(hdev); 174 175 return sprintf(buf, "%d\n", nd->sensor_physical_width); 176 } 177 178 static DEVICE_ATTR(sensor_physical_width, S_IRUGO, show_phys_width, NULL); 179 180 static ssize_t show_phys_height(struct device *dev, 181 struct device_attribute *attr, 182 char *buf) 183 { 184 struct hid_device *hdev = to_hid_device(dev); 185 struct ntrig_data *nd = hid_get_drvdata(hdev); 186 187 return sprintf(buf, "%d\n", nd->sensor_physical_height); 188 } 189 190 static DEVICE_ATTR(sensor_physical_height, S_IRUGO, show_phys_height, NULL); 191 192 static ssize_t show_log_width(struct device *dev, 193 struct device_attribute *attr, 194 char *buf) 195 { 196 struct hid_device *hdev = to_hid_device(dev); 197 struct ntrig_data *nd = hid_get_drvdata(hdev); 198 199 return sprintf(buf, "%d\n", nd->sensor_logical_width); 200 } 201 202 static DEVICE_ATTR(sensor_logical_width, S_IRUGO, show_log_width, NULL); 203 204 static ssize_t show_log_height(struct device *dev, 205 struct device_attribute *attr, 206 char *buf) 207 { 208 struct hid_device *hdev = to_hid_device(dev); 209 struct ntrig_data *nd = hid_get_drvdata(hdev); 210 211 return sprintf(buf, "%d\n", nd->sensor_logical_height); 212 } 213 214 static DEVICE_ATTR(sensor_logical_height, S_IRUGO, show_log_height, NULL); 215 216 static ssize_t show_min_width(struct device *dev, 217 struct device_attribute *attr, 218 char *buf) 219 { 220 struct hid_device *hdev = to_hid_device(dev); 221 struct ntrig_data *nd = hid_get_drvdata(hdev); 222 223 return sprintf(buf, "%d\n", nd->min_width * 224 nd->sensor_physical_width / 225 nd->sensor_logical_width); 226 } 227 228 static ssize_t set_min_width(struct device *dev, 229 struct device_attribute *attr, 230 const char *buf, size_t count) 231 { 232 struct hid_device *hdev = to_hid_device(dev); 233 struct ntrig_data *nd = hid_get_drvdata(hdev); 234 235 unsigned long val; 236 237 if (kstrtoul(buf, 0, &val)) 238 return -EINVAL; 239 240 if (val > nd->sensor_physical_width) 241 return -EINVAL; 242 243 nd->min_width = val * nd->sensor_logical_width / 244 nd->sensor_physical_width; 245 246 return count; 247 } 248 249 static DEVICE_ATTR(min_width, S_IWUSR | S_IRUGO, show_min_width, set_min_width); 250 251 static ssize_t show_min_height(struct device *dev, 252 struct device_attribute *attr, 253 char *buf) 254 { 255 struct hid_device *hdev = to_hid_device(dev); 256 struct ntrig_data *nd = hid_get_drvdata(hdev); 257 258 return sprintf(buf, "%d\n", nd->min_height * 259 nd->sensor_physical_height / 260 nd->sensor_logical_height); 261 } 262 263 static ssize_t set_min_height(struct device *dev, 264 struct device_attribute *attr, 265 const char *buf, size_t count) 266 { 267 struct hid_device *hdev = to_hid_device(dev); 268 struct ntrig_data *nd = hid_get_drvdata(hdev); 269 270 unsigned long val; 271 272 if (kstrtoul(buf, 0, &val)) 273 return -EINVAL; 274 275 if (val > nd->sensor_physical_height) 276 return -EINVAL; 277 278 nd->min_height = val * nd->sensor_logical_height / 279 nd->sensor_physical_height; 280 281 return count; 282 } 283 284 static DEVICE_ATTR(min_height, S_IWUSR | S_IRUGO, show_min_height, 285 set_min_height); 286 287 static ssize_t show_activate_slack(struct device *dev, 288 struct device_attribute *attr, 289 char *buf) 290 { 291 struct hid_device *hdev = to_hid_device(dev); 292 struct ntrig_data *nd = hid_get_drvdata(hdev); 293 294 return sprintf(buf, "%d\n", nd->activate_slack); 295 } 296 297 static ssize_t set_activate_slack(struct device *dev, 298 struct device_attribute *attr, 299 const char *buf, size_t count) 300 { 301 struct hid_device *hdev = to_hid_device(dev); 302 struct ntrig_data *nd = hid_get_drvdata(hdev); 303 304 unsigned long val; 305 306 if (kstrtoul(buf, 0, &val)) 307 return -EINVAL; 308 309 if (val > 0x7f) 310 return -EINVAL; 311 312 nd->activate_slack = val; 313 314 return count; 315 } 316 317 static DEVICE_ATTR(activate_slack, S_IWUSR | S_IRUGO, show_activate_slack, 318 set_activate_slack); 319 320 static ssize_t show_activation_width(struct device *dev, 321 struct device_attribute *attr, 322 char *buf) 323 { 324 struct hid_device *hdev = to_hid_device(dev); 325 struct ntrig_data *nd = hid_get_drvdata(hdev); 326 327 return sprintf(buf, "%d\n", nd->activation_width * 328 nd->sensor_physical_width / 329 nd->sensor_logical_width); 330 } 331 332 static ssize_t set_activation_width(struct device *dev, 333 struct device_attribute *attr, 334 const char *buf, size_t count) 335 { 336 struct hid_device *hdev = to_hid_device(dev); 337 struct ntrig_data *nd = hid_get_drvdata(hdev); 338 339 unsigned long val; 340 341 if (kstrtoul(buf, 0, &val)) 342 return -EINVAL; 343 344 if (val > nd->sensor_physical_width) 345 return -EINVAL; 346 347 nd->activation_width = val * nd->sensor_logical_width / 348 nd->sensor_physical_width; 349 350 return count; 351 } 352 353 static DEVICE_ATTR(activation_width, S_IWUSR | S_IRUGO, show_activation_width, 354 set_activation_width); 355 356 static ssize_t show_activation_height(struct device *dev, 357 struct device_attribute *attr, 358 char *buf) 359 { 360 struct hid_device *hdev = to_hid_device(dev); 361 struct ntrig_data *nd = hid_get_drvdata(hdev); 362 363 return sprintf(buf, "%d\n", nd->activation_height * 364 nd->sensor_physical_height / 365 nd->sensor_logical_height); 366 } 367 368 static ssize_t set_activation_height(struct device *dev, 369 struct device_attribute *attr, 370 const char *buf, size_t count) 371 { 372 struct hid_device *hdev = to_hid_device(dev); 373 struct ntrig_data *nd = hid_get_drvdata(hdev); 374 375 unsigned long val; 376 377 if (kstrtoul(buf, 0, &val)) 378 return -EINVAL; 379 380 if (val > nd->sensor_physical_height) 381 return -EINVAL; 382 383 nd->activation_height = val * nd->sensor_logical_height / 384 nd->sensor_physical_height; 385 386 return count; 387 } 388 389 static DEVICE_ATTR(activation_height, S_IWUSR | S_IRUGO, 390 show_activation_height, set_activation_height); 391 392 static ssize_t show_deactivate_slack(struct device *dev, 393 struct device_attribute *attr, 394 char *buf) 395 { 396 struct hid_device *hdev = to_hid_device(dev); 397 struct ntrig_data *nd = hid_get_drvdata(hdev); 398 399 return sprintf(buf, "%d\n", -nd->deactivate_slack); 400 } 401 402 static ssize_t set_deactivate_slack(struct device *dev, 403 struct device_attribute *attr, 404 const char *buf, size_t count) 405 { 406 struct hid_device *hdev = to_hid_device(dev); 407 struct ntrig_data *nd = hid_get_drvdata(hdev); 408 409 unsigned long val; 410 411 if (kstrtoul(buf, 0, &val)) 412 return -EINVAL; 413 414 /* 415 * No more than 8 terminal frames have been observed so far 416 * and higher slack is highly likely to leave the single 417 * touch emulation stuck down. 418 */ 419 if (val > 7) 420 return -EINVAL; 421 422 nd->deactivate_slack = -val; 423 424 return count; 425 } 426 427 static DEVICE_ATTR(deactivate_slack, S_IWUSR | S_IRUGO, show_deactivate_slack, 428 set_deactivate_slack); 429 430 static struct attribute *sysfs_attrs[] = { 431 &dev_attr_sensor_physical_width.attr, 432 &dev_attr_sensor_physical_height.attr, 433 &dev_attr_sensor_logical_width.attr, 434 &dev_attr_sensor_logical_height.attr, 435 &dev_attr_min_height.attr, 436 &dev_attr_min_width.attr, 437 &dev_attr_activate_slack.attr, 438 &dev_attr_activation_width.attr, 439 &dev_attr_activation_height.attr, 440 &dev_attr_deactivate_slack.attr, 441 NULL 442 }; 443 444 static const struct attribute_group ntrig_attribute_group = { 445 .attrs = sysfs_attrs 446 }; 447 448 /* 449 * this driver is aimed at two firmware versions in circulation: 450 * - dual pen/finger single touch 451 * - finger multitouch, pen not working 452 */ 453 454 static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi, 455 struct hid_field *field, struct hid_usage *usage, 456 unsigned long **bit, int *max) 457 { 458 struct ntrig_data *nd = hid_get_drvdata(hdev); 459 460 /* No special mappings needed for the pen and single touch */ 461 if (field->physical) 462 return 0; 463 464 switch (usage->hid & HID_USAGE_PAGE) { 465 case HID_UP_GENDESK: 466 switch (usage->hid) { 467 case HID_GD_X: 468 hid_map_usage(hi, usage, bit, max, 469 EV_ABS, ABS_MT_POSITION_X); 470 input_set_abs_params(hi->input, ABS_X, 471 field->logical_minimum, 472 field->logical_maximum, 0, 0); 473 474 if (!nd->sensor_logical_width) { 475 nd->sensor_logical_width = 476 field->logical_maximum - 477 field->logical_minimum; 478 nd->sensor_physical_width = 479 field->physical_maximum - 480 field->physical_minimum; 481 nd->activation_width = activation_width * 482 nd->sensor_logical_width / 483 nd->sensor_physical_width; 484 nd->min_width = min_width * 485 nd->sensor_logical_width / 486 nd->sensor_physical_width; 487 } 488 return 1; 489 case HID_GD_Y: 490 hid_map_usage(hi, usage, bit, max, 491 EV_ABS, ABS_MT_POSITION_Y); 492 input_set_abs_params(hi->input, ABS_Y, 493 field->logical_minimum, 494 field->logical_maximum, 0, 0); 495 496 if (!nd->sensor_logical_height) { 497 nd->sensor_logical_height = 498 field->logical_maximum - 499 field->logical_minimum; 500 nd->sensor_physical_height = 501 field->physical_maximum - 502 field->physical_minimum; 503 nd->activation_height = activation_height * 504 nd->sensor_logical_height / 505 nd->sensor_physical_height; 506 nd->min_height = min_height * 507 nd->sensor_logical_height / 508 nd->sensor_physical_height; 509 } 510 return 1; 511 } 512 return 0; 513 514 case HID_UP_DIGITIZER: 515 switch (usage->hid) { 516 /* we do not want to map these for now */ 517 case HID_DG_CONTACTID: /* Not trustworthy, squelch for now */ 518 case HID_DG_INPUTMODE: 519 case HID_DG_DEVICEINDEX: 520 case HID_DG_CONTACTMAX: 521 return -1; 522 523 /* width/height mapped on TouchMajor/TouchMinor/Orientation */ 524 case HID_DG_WIDTH: 525 hid_map_usage(hi, usage, bit, max, 526 EV_ABS, ABS_MT_TOUCH_MAJOR); 527 return 1; 528 case HID_DG_HEIGHT: 529 hid_map_usage(hi, usage, bit, max, 530 EV_ABS, ABS_MT_TOUCH_MINOR); 531 input_set_abs_params(hi->input, ABS_MT_ORIENTATION, 532 0, 1, 0, 0); 533 return 1; 534 } 535 return 0; 536 537 case 0xff000000: 538 /* we do not want to map these: no input-oriented meaning */ 539 return -1; 540 } 541 542 return 0; 543 } 544 545 static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi, 546 struct hid_field *field, struct hid_usage *usage, 547 unsigned long **bit, int *max) 548 { 549 /* No special mappings needed for the pen and single touch */ 550 if (field->physical) 551 return 0; 552 553 if (usage->type == EV_KEY || usage->type == EV_REL 554 || usage->type == EV_ABS) 555 clear_bit(usage->code, *bit); 556 557 return 0; 558 } 559 560 /* 561 * this function is called upon all reports 562 * so that we can filter contact point information, 563 * decide whether we are in multi or single touch mode 564 * and call input_mt_sync after each point if necessary 565 */ 566 static int ntrig_event (struct hid_device *hid, struct hid_field *field, 567 struct hid_usage *usage, __s32 value) 568 { 569 struct ntrig_data *nd = hid_get_drvdata(hid); 570 struct input_dev *input; 571 572 /* Skip processing if not a claimed input */ 573 if (!(hid->claimed & HID_CLAIMED_INPUT)) 574 goto not_claimed_input; 575 576 /* This function is being called before the structures are fully 577 * initialized */ 578 if(!(field->hidinput && field->hidinput->input)) 579 return -EINVAL; 580 581 input = field->hidinput->input; 582 583 /* No special handling needed for the pen */ 584 if (field->application == HID_DG_PEN) 585 return 0; 586 587 switch (usage->hid) { 588 case 0xff000001: 589 /* Tag indicating the start of a multitouch group */ 590 nd->reading_mt = true; 591 nd->first_contact_touch = false; 592 break; 593 case HID_DG_TIPSWITCH: 594 nd->tipswitch = value; 595 /* Prevent emission of touch until validated */ 596 return 1; 597 case HID_DG_CONFIDENCE: 598 nd->confidence = value; 599 break; 600 case HID_GD_X: 601 nd->x = value; 602 /* Clear the contact footer */ 603 nd->mt_foot_count = 0; 604 break; 605 case HID_GD_Y: 606 nd->y = value; 607 break; 608 case HID_DG_CONTACTID: 609 nd->id = value; 610 break; 611 case HID_DG_WIDTH: 612 nd->w = value; 613 break; 614 case HID_DG_HEIGHT: 615 nd->h = value; 616 /* 617 * when in single touch mode, this is the last 618 * report received in a finger event. We want 619 * to emit a normal (X, Y) position 620 */ 621 if (!nd->reading_mt) { 622 /* 623 * TipSwitch indicates the presence of a 624 * finger in single touch mode. 625 */ 626 input_report_key(input, BTN_TOUCH, 627 nd->tipswitch); 628 input_report_key(input, BTN_TOOL_DOUBLETAP, 629 nd->tipswitch); 630 input_event(input, EV_ABS, ABS_X, nd->x); 631 input_event(input, EV_ABS, ABS_Y, nd->y); 632 } 633 break; 634 case 0xff000002: 635 /* 636 * we receive this when the device is in multitouch 637 * mode. The first of the three values tagged with 638 * this usage tells if the contact point is real 639 * or a placeholder 640 */ 641 642 /* Shouldn't get more than 4 footer packets, so skip */ 643 if (nd->mt_foot_count >= 4) 644 break; 645 646 nd->mt_footer[nd->mt_foot_count++] = value; 647 648 /* if the footer isn't complete break */ 649 if (nd->mt_foot_count != 4) 650 break; 651 652 /* Pen activity signal. */ 653 if (nd->mt_footer[2]) { 654 /* 655 * When the pen deactivates touch, we see a 656 * bogus frame with ContactCount > 0. 657 * We can 658 * save a bit of work by ensuring act_state < 0 659 * even if deactivation slack is turned off. 660 */ 661 nd->act_state = deactivate_slack - 1; 662 nd->confidence = false; 663 break; 664 } 665 666 /* 667 * The first footer value indicates the presence of a 668 * finger. 669 */ 670 if (nd->mt_footer[0]) { 671 /* 672 * We do not want to process contacts under 673 * the size threshold, but do not want to 674 * ignore them for activation state 675 */ 676 if (nd->w < nd->min_width || 677 nd->h < nd->min_height) 678 nd->confidence = false; 679 } else 680 break; 681 682 if (nd->act_state > 0) { 683 /* 684 * Contact meets the activation size threshold 685 */ 686 if (nd->w >= nd->activation_width && 687 nd->h >= nd->activation_height) { 688 if (nd->id) 689 /* 690 * first contact, activate now 691 */ 692 nd->act_state = 0; 693 else { 694 /* 695 * avoid corrupting this frame 696 * but ensure next frame will 697 * be active 698 */ 699 nd->act_state = 1; 700 break; 701 } 702 } else 703 /* 704 * Defer adjusting the activation state 705 * until the end of the frame. 706 */ 707 break; 708 } 709 710 /* Discarding this contact */ 711 if (!nd->confidence) 712 break; 713 714 /* emit a normal (X, Y) for the first point only */ 715 if (nd->id == 0) { 716 /* 717 * TipSwitch is superfluous in multitouch 718 * mode. The footer events tell us 719 * if there is a finger on the screen or 720 * not. 721 */ 722 nd->first_contact_touch = nd->confidence; 723 input_event(input, EV_ABS, ABS_X, nd->x); 724 input_event(input, EV_ABS, ABS_Y, nd->y); 725 } 726 727 /* Emit MT events */ 728 input_event(input, EV_ABS, ABS_MT_POSITION_X, nd->x); 729 input_event(input, EV_ABS, ABS_MT_POSITION_Y, nd->y); 730 731 /* 732 * Translate from height and width to size 733 * and orientation. 734 */ 735 if (nd->w > nd->h) { 736 input_event(input, EV_ABS, 737 ABS_MT_ORIENTATION, 1); 738 input_event(input, EV_ABS, 739 ABS_MT_TOUCH_MAJOR, nd->w); 740 input_event(input, EV_ABS, 741 ABS_MT_TOUCH_MINOR, nd->h); 742 } else { 743 input_event(input, EV_ABS, 744 ABS_MT_ORIENTATION, 0); 745 input_event(input, EV_ABS, 746 ABS_MT_TOUCH_MAJOR, nd->h); 747 input_event(input, EV_ABS, 748 ABS_MT_TOUCH_MINOR, nd->w); 749 } 750 input_mt_sync(field->hidinput->input); 751 break; 752 753 case HID_DG_CONTACTCOUNT: /* End of a multitouch group */ 754 if (!nd->reading_mt) /* Just to be sure */ 755 break; 756 757 nd->reading_mt = false; 758 759 760 /* 761 * Activation state machine logic: 762 * 763 * Fundamental states: 764 * state > 0: Inactive 765 * state <= 0: Active 766 * state < -deactivate_slack: 767 * Pen termination of touch 768 * 769 * Specific values of interest 770 * state == activate_slack 771 * no valid input since the last reset 772 * 773 * state == 0 774 * general operational state 775 * 776 * state == -deactivate_slack 777 * read sufficient empty frames to accept 778 * the end of input and reset 779 */ 780 781 if (nd->act_state > 0) { /* Currently inactive */ 782 if (value) 783 /* 784 * Consider each live contact as 785 * evidence of intentional activity. 786 */ 787 nd->act_state = (nd->act_state > value) 788 ? nd->act_state - value 789 : 0; 790 else 791 /* 792 * Empty frame before we hit the 793 * activity threshold, reset. 794 */ 795 nd->act_state = nd->activate_slack; 796 797 /* 798 * Entered this block inactive and no 799 * coordinates sent this frame, so hold off 800 * on button state. 801 */ 802 break; 803 } else { /* Currently active */ 804 if (value && nd->act_state >= 805 nd->deactivate_slack) 806 /* 807 * Live point: clear accumulated 808 * deactivation count. 809 */ 810 nd->act_state = 0; 811 else if (nd->act_state <= nd->deactivate_slack) 812 /* 813 * We've consumed the deactivation 814 * slack, time to deactivate and reset. 815 */ 816 nd->act_state = 817 nd->activate_slack; 818 else { /* Move towards deactivation */ 819 nd->act_state--; 820 break; 821 } 822 } 823 824 if (nd->first_contact_touch && nd->act_state <= 0) { 825 /* 826 * Check to see if we're ready to start 827 * emitting touch events. 828 * 829 * Note: activation slack will decrease over 830 * the course of the frame, and it will be 831 * inconsistent from the start to the end of 832 * the frame. However if the frame starts 833 * with slack, first_contact_touch will still 834 * be 0 and we will not get to this point. 835 */ 836 input_report_key(input, BTN_TOOL_DOUBLETAP, 1); 837 input_report_key(input, BTN_TOUCH, 1); 838 } else { 839 input_report_key(input, BTN_TOOL_DOUBLETAP, 0); 840 input_report_key(input, BTN_TOUCH, 0); 841 } 842 break; 843 844 default: 845 /* fall-back to the generic hidinput handling */ 846 return 0; 847 } 848 849 not_claimed_input: 850 851 /* we have handled the hidinput part, now remains hiddev */ 852 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_hid_event) 853 hid->hiddev_hid_event(hid, field, usage, value); 854 855 return 1; 856 } 857 858 static int ntrig_input_configured(struct hid_device *hid, 859 struct hid_input *hidinput) 860 861 { 862 struct input_dev *input = hidinput->input; 863 864 if (hidinput->report->maxfield < 1) 865 return 0; 866 867 switch (hidinput->report->field[0]->application) { 868 case HID_DG_PEN: 869 input->name = "N-Trig Pen"; 870 break; 871 case HID_DG_TOUCHSCREEN: 872 /* These keys are redundant for fingers, clear them 873 * to prevent incorrect identification */ 874 __clear_bit(BTN_TOOL_PEN, input->keybit); 875 __clear_bit(BTN_TOOL_FINGER, input->keybit); 876 __clear_bit(BTN_0, input->keybit); 877 __set_bit(BTN_TOOL_DOUBLETAP, input->keybit); 878 /* 879 * The physical touchscreen (single touch) 880 * input has a value for physical, whereas 881 * the multitouch only has logical input 882 * fields. 883 */ 884 input->name = (hidinput->report->field[0]->physical) ? 885 "N-Trig Touchscreen" : 886 "N-Trig MultiTouch"; 887 break; 888 } 889 890 return 0; 891 } 892 893 static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id) 894 { 895 int ret; 896 struct ntrig_data *nd; 897 struct hid_report *report; 898 899 if (id->driver_data) 900 hdev->quirks |= HID_QUIRK_MULTI_INPUT 901 | HID_QUIRK_NO_INIT_REPORTS; 902 903 nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL); 904 if (!nd) { 905 hid_err(hdev, "cannot allocate N-Trig data\n"); 906 return -ENOMEM; 907 } 908 909 nd->reading_mt = false; 910 nd->min_width = 0; 911 nd->min_height = 0; 912 nd->activate_slack = activate_slack; 913 nd->act_state = activate_slack; 914 nd->deactivate_slack = -deactivate_slack; 915 nd->sensor_logical_width = 1; 916 nd->sensor_logical_height = 1; 917 nd->sensor_physical_width = 1; 918 nd->sensor_physical_height = 1; 919 920 hid_set_drvdata(hdev, nd); 921 922 ret = hid_parse(hdev); 923 if (ret) { 924 hid_err(hdev, "parse failed\n"); 925 goto err_free; 926 } 927 928 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF); 929 if (ret) { 930 hid_err(hdev, "hw start failed\n"); 931 goto err_free; 932 } 933 934 /* This is needed for devices with more recent firmware versions */ 935 report = hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0x0a]; 936 if (report) { 937 /* Let the device settle to ensure the wakeup message gets 938 * through */ 939 hid_hw_wait(hdev); 940 hid_hw_request(hdev, report, HID_REQ_GET_REPORT); 941 942 /* 943 * Sanity check: if the current mode is invalid reset it to 944 * something reasonable. 945 */ 946 if (ntrig_get_mode(hdev) >= 4) 947 ntrig_set_mode(hdev, 3); 948 } 949 950 ntrig_report_version(hdev); 951 952 ret = sysfs_create_group(&hdev->dev.kobj, 953 &ntrig_attribute_group); 954 if (ret) 955 hid_err(hdev, "cannot create sysfs group\n"); 956 957 return 0; 958 err_free: 959 kfree(nd); 960 return ret; 961 } 962 963 static void ntrig_remove(struct hid_device *hdev) 964 { 965 sysfs_remove_group(&hdev->dev.kobj, 966 &ntrig_attribute_group); 967 hid_hw_stop(hdev); 968 kfree(hid_get_drvdata(hdev)); 969 } 970 971 static const struct hid_device_id ntrig_devices[] = { 972 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN), 973 .driver_data = NTRIG_DUPLICATE_USAGES }, 974 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_1), 975 .driver_data = NTRIG_DUPLICATE_USAGES }, 976 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_2), 977 .driver_data = NTRIG_DUPLICATE_USAGES }, 978 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_3), 979 .driver_data = NTRIG_DUPLICATE_USAGES }, 980 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_4), 981 .driver_data = NTRIG_DUPLICATE_USAGES }, 982 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_5), 983 .driver_data = NTRIG_DUPLICATE_USAGES }, 984 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_6), 985 .driver_data = NTRIG_DUPLICATE_USAGES }, 986 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_7), 987 .driver_data = NTRIG_DUPLICATE_USAGES }, 988 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_8), 989 .driver_data = NTRIG_DUPLICATE_USAGES }, 990 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_9), 991 .driver_data = NTRIG_DUPLICATE_USAGES }, 992 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_10), 993 .driver_data = NTRIG_DUPLICATE_USAGES }, 994 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_11), 995 .driver_data = NTRIG_DUPLICATE_USAGES }, 996 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_12), 997 .driver_data = NTRIG_DUPLICATE_USAGES }, 998 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_13), 999 .driver_data = NTRIG_DUPLICATE_USAGES }, 1000 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_14), 1001 .driver_data = NTRIG_DUPLICATE_USAGES }, 1002 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_15), 1003 .driver_data = NTRIG_DUPLICATE_USAGES }, 1004 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_16), 1005 .driver_data = NTRIG_DUPLICATE_USAGES }, 1006 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_17), 1007 .driver_data = NTRIG_DUPLICATE_USAGES }, 1008 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_18), 1009 .driver_data = NTRIG_DUPLICATE_USAGES }, 1010 { } 1011 }; 1012 MODULE_DEVICE_TABLE(hid, ntrig_devices); 1013 1014 static const struct hid_usage_id ntrig_grabbed_usages[] = { 1015 { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID }, 1016 { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1 } 1017 }; 1018 1019 static struct hid_driver ntrig_driver = { 1020 .name = "ntrig", 1021 .id_table = ntrig_devices, 1022 .probe = ntrig_probe, 1023 .remove = ntrig_remove, 1024 .input_mapping = ntrig_input_mapping, 1025 .input_mapped = ntrig_input_mapped, 1026 .input_configured = ntrig_input_configured, 1027 .usage_table = ntrig_grabbed_usages, 1028 .event = ntrig_event, 1029 }; 1030 module_hid_driver(ntrig_driver); 1031 1032 MODULE_DESCRIPTION("HID driver for N-Trig touchscreens"); 1033 MODULE_LICENSE("GPL"); 1034