1/*
2 * HID driver for N-Trig touchscreens
3 *
4 * Copyright (c) 2008-2010 Rafi Rubin
5 * Copyright (c) 2009-2010 Stephane Chatty
6 *
7 */
8
9/*
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the Free
12 * Software Foundation; either version 2 of the License, or (at your option)
13 * any later version.
14 */
15
16#include <linux/device.h>
17#include <linux/hid.h>
18#include <linux/usb.h>
19#include "usbhid/usbhid.h"
20#include <linux/module.h>
21#include <linux/slab.h>
22
23#include "hid-ids.h"
24
25#define NTRIG_DUPLICATE_USAGES 0x001
26
27static unsigned int min_width;
28module_param(min_width, uint, 0644);
29MODULE_PARM_DESC(min_width, "Minimum touch contact width to accept.");
30
31static unsigned int min_height;
32module_param(min_height, uint, 0644);
33MODULE_PARM_DESC(min_height, "Minimum touch contact height to accept.");
34
35static unsigned int activate_slack = 1;
36module_param(activate_slack, uint, 0644);
37MODULE_PARM_DESC(activate_slack, "Number of touch frames to ignore at "
38 "the start of touch input.");
39
40static unsigned int deactivate_slack = 4;
41module_param(deactivate_slack, uint, 0644);
42MODULE_PARM_DESC(deactivate_slack, "Number of empty frames to ignore before "
43 "deactivating touch.");
44
45static unsigned int activation_width = 64;
46module_param(activation_width, uint, 0644);
47MODULE_PARM_DESC(activation_width, "Width threshold to immediately start "
48 "processing touch events.");
49
50static unsigned int activation_height = 32;
51module_param(activation_height, uint, 0644);
52MODULE_PARM_DESC(activation_height, "Height threshold to immediately start "
53 "processing touch events.");
54
55struct ntrig_data {
56 /* Incoming raw values for a single contact */
57 __u16 x, y, w, h;
58 __u16 id;
59
60 bool tipswitch;
61 bool confidence;
62 bool first_contact_touch;
63
64 bool reading_mt;
65
66 __u8 mt_footer[4];
67 __u8 mt_foot_count;
68
69 /* The current activation state. */
70 __s8 act_state;
71
72 /* Empty frames to ignore before recognizing the end of activity */
73 __s8 deactivate_slack;
74
75 /* Frames to ignore before acknowledging the start of activity */
76 __s8 activate_slack;
77
78 /* Minimum size contact to accept */
79 __u16 min_width;
80 __u16 min_height;
81
82 /* Threshold to override activation slack */
83 __u16 activation_width;
84 __u16 activation_height;
85
86 __u16 sensor_logical_width;
87 __u16 sensor_logical_height;
88 __u16 sensor_physical_width;
89 __u16 sensor_physical_height;
90};
91
92
93/*
94 * This function converts the 4 byte raw firmware code into
95 * a string containing 5 comma separated numbers.
96 */
97static int ntrig_version_string(unsigned char *raw, char *buf)
98{
99 __u8 a = (raw[1] & 0x0e) >> 1;
100 __u8 b = (raw[0] & 0x3c) >> 2;
101 __u8 c = ((raw[0] & 0x03) << 3) | ((raw[3] & 0xe0) >> 5);
102 __u8 d = ((raw[3] & 0x07) << 3) | ((raw[2] & 0xe0) >> 5);
103 __u8 e = raw[2] & 0x07;
104
105 /*
106 * As yet unmapped bits:
107 * 0b11000000 0b11110001 0b00011000 0b00011000
108 */
109
110 return sprintf(buf, "%u.%u.%u.%u.%u", a, b, c, d, e);
111}
112
113static inline int ntrig_get_mode(struct hid_device *hdev)
114{
115 struct hid_report *report = hdev->report_enum[HID_FEATURE_REPORT].
116 report_id_hash[0x0d];
117
118 if (!report || report->maxfield < 1 ||
119 report->field[0]->report_count < 1)
120 return -EINVAL;
121
122 hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
123 hid_hw_wait(hdev);
124 return (int)report->field[0]->value[0];
125}
126
127static inline void ntrig_set_mode(struct hid_device *hdev, const int mode)
128{
129 struct hid_report *report;
130 __u8 mode_commands[4] = { 0xe, 0xf, 0x1b, 0x10 };
131
132 if (mode < 0 || mode > 3)
133 return;
134
135 report = hdev->report_enum[HID_FEATURE_REPORT].
136 report_id_hash[mode_commands[mode]];
137
138 if (!report)
139 return;
140
141 hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
142}
143
144static void ntrig_report_version(struct hid_device *hdev)
145{
146 int ret;
147 char buf[20];
148 struct usb_device *usb_dev = hid_to_usb_dev(hdev);
149 unsigned char *data = kmalloc(8, GFP_KERNEL);
150
151 if (!data)
152 goto err_free;
153
154 ret = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
155 USB_REQ_CLEAR_FEATURE,
156 USB_TYPE_CLASS | USB_RECIP_INTERFACE |
157 USB_DIR_IN,
158 0x30c, 1, data, 8,
159 USB_CTRL_SET_TIMEOUT);
160
161 if (ret == 8) {
162 ret = ntrig_version_string(&data[2], buf);
163
164 hid_info(hdev, "Firmware version: %s (%02x%02x %02x%02x)\n",
165 buf, data[2], data[3], data[4], data[5]);
166 }
167
168err_free:
169 kfree(data);
170}
171
172static ssize_t show_phys_width(struct device *dev,
173 struct device_attribute *attr,
174 char *buf)
175{
176 struct hid_device *hdev = to_hid_device(dev);
177 struct ntrig_data *nd = hid_get_drvdata(hdev);
178
179 return sprintf(buf, "%d\n", nd->sensor_physical_width);
180}
181
182static DEVICE_ATTR(sensor_physical_width, S_IRUGO, show_phys_width, NULL);
183
184static ssize_t show_phys_height(struct device *dev,
185 struct device_attribute *attr,
186 char *buf)
187{
188 struct hid_device *hdev = to_hid_device(dev);
189 struct ntrig_data *nd = hid_get_drvdata(hdev);
190
191 return sprintf(buf, "%d\n", nd->sensor_physical_height);
192}
193
194static DEVICE_ATTR(sensor_physical_height, S_IRUGO, show_phys_height, NULL);
195
196static ssize_t show_log_width(struct device *dev,
197 struct device_attribute *attr,
198 char *buf)
199{
200 struct hid_device *hdev = to_hid_device(dev);
201 struct ntrig_data *nd = hid_get_drvdata(hdev);
202
203 return sprintf(buf, "%d\n", nd->sensor_logical_width);
204}
205
206static DEVICE_ATTR(sensor_logical_width, S_IRUGO, show_log_width, NULL);
207
208static ssize_t show_log_height(struct device *dev,
209 struct device_attribute *attr,
210 char *buf)
211{
212 struct hid_device *hdev = to_hid_device(dev);
213 struct ntrig_data *nd = hid_get_drvdata(hdev);
214
215 return sprintf(buf, "%d\n", nd->sensor_logical_height);
216}
217
218static DEVICE_ATTR(sensor_logical_height, S_IRUGO, show_log_height, NULL);
219
220static ssize_t show_min_width(struct device *dev,
221 struct device_attribute *attr,
222 char *buf)
223{
224 struct hid_device *hdev = to_hid_device(dev);
225 struct ntrig_data *nd = hid_get_drvdata(hdev);
226
227 return sprintf(buf, "%d\n", nd->min_width *
228 nd->sensor_physical_width /
229 nd->sensor_logical_width);
230}
231
232static ssize_t set_min_width(struct device *dev,
233 struct device_attribute *attr,
234 const char *buf, size_t count)
235{
236 struct hid_device *hdev = to_hid_device(dev);
237 struct ntrig_data *nd = hid_get_drvdata(hdev);
238
239 unsigned long val;
240
241 if (kstrtoul(buf, 0, &val))
242 return -EINVAL;
243
244 if (val > nd->sensor_physical_width)
245 return -EINVAL;
246
247 nd->min_width = val * nd->sensor_logical_width /
248 nd->sensor_physical_width;
249
250 return count;
251}
252
253static DEVICE_ATTR(min_width, S_IWUSR | S_IRUGO, show_min_width, set_min_width);
254
255static ssize_t show_min_height(struct device *dev,
256 struct device_attribute *attr,
257 char *buf)
258{
259 struct hid_device *hdev = to_hid_device(dev);
260 struct ntrig_data *nd = hid_get_drvdata(hdev);
261
262 return sprintf(buf, "%d\n", nd->min_height *
263 nd->sensor_physical_height /
264 nd->sensor_logical_height);
265}
266
267static ssize_t set_min_height(struct device *dev,
268 struct device_attribute *attr,
269 const char *buf, size_t count)
270{
271 struct hid_device *hdev = to_hid_device(dev);
272 struct ntrig_data *nd = hid_get_drvdata(hdev);
273
274 unsigned long val;
275
276 if (kstrtoul(buf, 0, &val))
277 return -EINVAL;
278
279 if (val > nd->sensor_physical_height)
280 return -EINVAL;
281
282 nd->min_height = val * nd->sensor_logical_height /
283 nd->sensor_physical_height;
284
285 return count;
286}
287
288static DEVICE_ATTR(min_height, S_IWUSR | S_IRUGO, show_min_height,
289 set_min_height);
290
291static ssize_t show_activate_slack(struct device *dev,
292 struct device_attribute *attr,
293 char *buf)
294{
295 struct hid_device *hdev = to_hid_device(dev);
296 struct ntrig_data *nd = hid_get_drvdata(hdev);
297
298 return sprintf(buf, "%d\n", nd->activate_slack);
299}
300
301static ssize_t set_activate_slack(struct device *dev,
302 struct device_attribute *attr,
303 const char *buf, size_t count)
304{
305 struct hid_device *hdev = to_hid_device(dev);
306 struct ntrig_data *nd = hid_get_drvdata(hdev);
307
308 unsigned long val;
309
310 if (kstrtoul(buf, 0, &val))
311 return -EINVAL;
312
313 if (val > 0x7f)
314 return -EINVAL;
315
316 nd->activate_slack = val;
317
318 return count;
319}
320
321static DEVICE_ATTR(activate_slack, S_IWUSR | S_IRUGO, show_activate_slack,
322 set_activate_slack);
323
324static ssize_t show_activation_width(struct device *dev,
325 struct device_attribute *attr,
326 char *buf)
327{
328 struct hid_device *hdev = to_hid_device(dev);
329 struct ntrig_data *nd = hid_get_drvdata(hdev);
330
331 return sprintf(buf, "%d\n", nd->activation_width *
332 nd->sensor_physical_width /
333 nd->sensor_logical_width);
334}
335
336static ssize_t set_activation_width(struct device *dev,
337 struct device_attribute *attr,
338 const char *buf, size_t count)
339{
340 struct hid_device *hdev = to_hid_device(dev);
341 struct ntrig_data *nd = hid_get_drvdata(hdev);
342
343 unsigned long val;
344
345 if (kstrtoul(buf, 0, &val))
346 return -EINVAL;
347
348 if (val > nd->sensor_physical_width)
349 return -EINVAL;
350
351 nd->activation_width = val * nd->sensor_logical_width /
352 nd->sensor_physical_width;
353
354 return count;
355}
356
357static DEVICE_ATTR(activation_width, S_IWUSR | S_IRUGO, show_activation_width,
358 set_activation_width);
359
360static ssize_t show_activation_height(struct device *dev,
361 struct device_attribute *attr,
362 char *buf)
363{
364 struct hid_device *hdev = to_hid_device(dev);
365 struct ntrig_data *nd = hid_get_drvdata(hdev);
366
367 return sprintf(buf, "%d\n", nd->activation_height *
368 nd->sensor_physical_height /
369 nd->sensor_logical_height);
370}
371
372static ssize_t set_activation_height(struct device *dev,
373 struct device_attribute *attr,
374 const char *buf, size_t count)
375{
376 struct hid_device *hdev = to_hid_device(dev);
377 struct ntrig_data *nd = hid_get_drvdata(hdev);
378
379 unsigned long val;
380
381 if (kstrtoul(buf, 0, &val))
382 return -EINVAL;
383
384 if (val > nd->sensor_physical_height)
385 return -EINVAL;
386
387 nd->activation_height = val * nd->sensor_logical_height /
388 nd->sensor_physical_height;
389
390 return count;
391}
392
393static DEVICE_ATTR(activation_height, S_IWUSR | S_IRUGO,
394 show_activation_height, set_activation_height);
395
396static ssize_t show_deactivate_slack(struct device *dev,
397 struct device_attribute *attr,
398 char *buf)
399{
400 struct hid_device *hdev = to_hid_device(dev);
401 struct ntrig_data *nd = hid_get_drvdata(hdev);
402
403 return sprintf(buf, "%d\n", -nd->deactivate_slack);
404}
405
406static ssize_t set_deactivate_slack(struct device *dev,
407 struct device_attribute *attr,
408 const char *buf, size_t count)
409{
410 struct hid_device *hdev = to_hid_device(dev);
411 struct ntrig_data *nd = hid_get_drvdata(hdev);
412
413 unsigned long val;
414
415 if (kstrtoul(buf, 0, &val))
416 return -EINVAL;
417
418 /*
419 * No more than 8 terminal frames have been observed so far
420 * and higher slack is highly likely to leave the single
421 * touch emulation stuck down.
422 */
423 if (val > 7)
424 return -EINVAL;
425
426 nd->deactivate_slack = -val;
427
428 return count;
429}
430
431static DEVICE_ATTR(deactivate_slack, S_IWUSR | S_IRUGO, show_deactivate_slack,
432 set_deactivate_slack);
433
434static struct attribute *sysfs_attrs[] = {
435 &dev_attr_sensor_physical_width.attr,
436 &dev_attr_sensor_physical_height.attr,
437 &dev_attr_sensor_logical_width.attr,
438 &dev_attr_sensor_logical_height.attr,
439 &dev_attr_min_height.attr,
440 &dev_attr_min_width.attr,
441 &dev_attr_activate_slack.attr,
442 &dev_attr_activation_width.attr,
443 &dev_attr_activation_height.attr,
444 &dev_attr_deactivate_slack.attr,
445 NULL
446};
447
448static const struct attribute_group ntrig_attribute_group = {
449 .attrs = sysfs_attrs
450};
451
452/*
453 * this driver is aimed at two firmware versions in circulation:
454 * - dual pen/finger single touch
455 * - finger multitouch, pen not working
456 */
457
458static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi,
459 struct hid_field *field, struct hid_usage *usage,
460 unsigned long **bit, int *max)
461{
462 struct ntrig_data *nd = hid_get_drvdata(hdev);
463
464 /* No special mappings needed for the pen and single touch */
465 if (field->physical)
466 return 0;
467
468 switch (usage->hid & HID_USAGE_PAGE) {
469 case HID_UP_GENDESK:
470 switch (usage->hid) {
471 case HID_GD_X:
472 hid_map_usage(hi, usage, bit, max,
473 EV_ABS, ABS_MT_POSITION_X);
474 input_set_abs_params(hi->input, ABS_X,
475 field->logical_minimum,
476 field->logical_maximum, 0, 0);
477
478 if (!nd->sensor_logical_width) {
479 nd->sensor_logical_width =
480 field->logical_maximum -
481 field->logical_minimum;
482 nd->sensor_physical_width =
483 field->physical_maximum -
484 field->physical_minimum;
485 nd->activation_width = activation_width *
486 nd->sensor_logical_width /
487 nd->sensor_physical_width;
488 nd->min_width = min_width *
489 nd->sensor_logical_width /
490 nd->sensor_physical_width;
491 }
492 return 1;
493 case HID_GD_Y:
494 hid_map_usage(hi, usage, bit, max,
495 EV_ABS, ABS_MT_POSITION_Y);
496 input_set_abs_params(hi->input, ABS_Y,
497 field->logical_minimum,
498 field->logical_maximum, 0, 0);
499
500 if (!nd->sensor_logical_height) {
501 nd->sensor_logical_height =
502 field->logical_maximum -
503 field->logical_minimum;
504 nd->sensor_physical_height =
505 field->physical_maximum -
506 field->physical_minimum;
507 nd->activation_height = activation_height *
508 nd->sensor_logical_height /
509 nd->sensor_physical_height;
510 nd->min_height = min_height *
511 nd->sensor_logical_height /
512 nd->sensor_physical_height;
513 }
514 return 1;
515 }
516 return 0;
517
518 case HID_UP_DIGITIZER:
519 switch (usage->hid) {
520 /* we do not want to map these for now */
521 case HID_DG_CONTACTID: /* Not trustworthy, squelch for now */
522 case HID_DG_INPUTMODE:
523 case HID_DG_DEVICEINDEX:
524 case HID_DG_CONTACTMAX:
525 return -1;
526
527 /* width/height mapped on TouchMajor/TouchMinor/Orientation */
528 case HID_DG_WIDTH:
529 hid_map_usage(hi, usage, bit, max,
530 EV_ABS, ABS_MT_TOUCH_MAJOR);
531 return 1;
532 case HID_DG_HEIGHT:
533 hid_map_usage(hi, usage, bit, max,
534 EV_ABS, ABS_MT_TOUCH_MINOR);
535 input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
536 0, 1, 0, 0);
537 return 1;
538 }
539 return 0;
540
541 case 0xff000000:
542 /* we do not want to map these: no input-oriented meaning */
543 return -1;
544 }
545
546 return 0;
547}
548
549static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi,
550 struct hid_field *field, struct hid_usage *usage,
551 unsigned long **bit, int *max)
552{
553 /* No special mappings needed for the pen and single touch */
554 if (field->physical)
555 return 0;
556
557 if (usage->type == EV_KEY || usage->type == EV_REL
558 || usage->type == EV_ABS)
559 clear_bit(usage->code, *bit);
560
561 return 0;
562}
563
564/*
565 * this function is called upon all reports
566 * so that we can filter contact point information,
567 * decide whether we are in multi or single touch mode
568 * and call input_mt_sync after each point if necessary
569 */
570static int ntrig_event (struct hid_device *hid, struct hid_field *field,
571 struct hid_usage *usage, __s32 value)
572{
573 struct ntrig_data *nd = hid_get_drvdata(hid);
574 struct input_dev *input;
575
576 /* Skip processing if not a claimed input */
577 if (!(hid->claimed & HID_CLAIMED_INPUT))
578 goto not_claimed_input;
579
580 /* This function is being called before the structures are fully
581 * initialized */
582 if(!(field->hidinput && field->hidinput->input))
583 return -EINVAL;
584
585 input = field->hidinput->input;
586
587 /* No special handling needed for the pen */
588 if (field->application == HID_DG_PEN)
589 return 0;
590
591 switch (usage->hid) {
592 case 0xff000001:
593 /* Tag indicating the start of a multitouch group */
594 nd->reading_mt = true;
595 nd->first_contact_touch = false;
596 break;
597 case HID_DG_TIPSWITCH:
598 nd->tipswitch = value;
599 /* Prevent emission of touch until validated */
600 return 1;
601 case HID_DG_CONFIDENCE:
602 nd->confidence = value;
603 break;
604 case HID_GD_X:
605 nd->x = value;
606 /* Clear the contact footer */
607 nd->mt_foot_count = 0;
608 break;
609 case HID_GD_Y:
610 nd->y = value;
611 break;
612 case HID_DG_CONTACTID:
613 nd->id = value;
614 break;
615 case HID_DG_WIDTH:
616 nd->w = value;
617 break;
618 case HID_DG_HEIGHT:
619 nd->h = value;
620 /*
621 * when in single touch mode, this is the last
622 * report received in a finger event. We want
623 * to emit a normal (X, Y) position
624 */
625 if (!nd->reading_mt) {
626 /*
627 * TipSwitch indicates the presence of a
628 * finger in single touch mode.
629 */
630 input_report_key(input, BTN_TOUCH,
631 nd->tipswitch);
632 input_report_key(input, BTN_TOOL_DOUBLETAP,
633 nd->tipswitch);
634 input_event(input, EV_ABS, ABS_X, nd->x);
635 input_event(input, EV_ABS, ABS_Y, nd->y);
636 }
637 break;
638 case 0xff000002:
639 /*
640 * we receive this when the device is in multitouch
641 * mode. The first of the three values tagged with
642 * this usage tells if the contact point is real
643 * or a placeholder
644 */
645
646 /* Shouldn't get more than 4 footer packets, so skip */
647 if (nd->mt_foot_count >= 4)
648 break;
649
650 nd->mt_footer[nd->mt_foot_count++] = value;
651
652 /* if the footer isn't complete break */
653 if (nd->mt_foot_count != 4)
654 break;
655
656 /* Pen activity signal. */
657 if (nd->mt_footer[2]) {
658 /*
659 * When the pen deactivates touch, we see a
660 * bogus frame with ContactCount > 0.
661 * We can
662 * save a bit of work by ensuring act_state < 0
663 * even if deactivation slack is turned off.
664 */
665 nd->act_state = deactivate_slack - 1;
666 nd->confidence = false;
667 break;
668 }
669
670 /*
671 * The first footer value indicates the presence of a
672 * finger.
673 */
674 if (nd->mt_footer[0]) {
675 /*
676 * We do not want to process contacts under
677 * the size threshold, but do not want to
678 * ignore them for activation state
679 */
680 if (nd->w < nd->min_width ||
681 nd->h < nd->min_height)
682 nd->confidence = false;
683 } else
684 break;
685
686 if (nd->act_state > 0) {
687 /*
688 * Contact meets the activation size threshold
689 */
690 if (nd->w >= nd->activation_width &&
691 nd->h >= nd->activation_height) {
692 if (nd->id)
693 /*
694 * first contact, activate now
695 */
696 nd->act_state = 0;
697 else {
698 /*
699 * avoid corrupting this frame
700 * but ensure next frame will
701 * be active
702 */
703 nd->act_state = 1;
704 break;
705 }
706 } else
707 /*
708 * Defer adjusting the activation state
709 * until the end of the frame.
710 */
711 break;
712 }
713
714 /* Discarding this contact */
715 if (!nd->confidence)
716 break;
717
718 /* emit a normal (X, Y) for the first point only */
719 if (nd->id == 0) {
720 /*
721 * TipSwitch is superfluous in multitouch
722 * mode. The footer events tell us
723 * if there is a finger on the screen or
724 * not.
725 */
726 nd->first_contact_touch = nd->confidence;
727 input_event(input, EV_ABS, ABS_X, nd->x);
728 input_event(input, EV_ABS, ABS_Y, nd->y);
729 }
730
731 /* Emit MT events */
732 input_event(input, EV_ABS, ABS_MT_POSITION_X, nd->x);
733 input_event(input, EV_ABS, ABS_MT_POSITION_Y, nd->y);
734
735 /*
736 * Translate from height and width to size
737 * and orientation.
738 */
739 if (nd->w > nd->h) {
740 input_event(input, EV_ABS,
741 ABS_MT_ORIENTATION, 1);
742 input_event(input, EV_ABS,
743 ABS_MT_TOUCH_MAJOR, nd->w);
744 input_event(input, EV_ABS,
745 ABS_MT_TOUCH_MINOR, nd->h);
746 } else {
747 input_event(input, EV_ABS,
748 ABS_MT_ORIENTATION, 0);
749 input_event(input, EV_ABS,
750 ABS_MT_TOUCH_MAJOR, nd->h);
751 input_event(input, EV_ABS,
752 ABS_MT_TOUCH_MINOR, nd->w);
753 }
754 input_mt_sync(field->hidinput->input);
755 break;
756
757 case HID_DG_CONTACTCOUNT: /* End of a multitouch group */
758 if (!nd->reading_mt) /* Just to be sure */
759 break;
760
761 nd->reading_mt = false;
762
763
764 /*
765 * Activation state machine logic:
766 *
767 * Fundamental states:
768 * state > 0: Inactive
769 * state <= 0: Active
770 * state < -deactivate_slack:
771 * Pen termination of touch
772 *
773 * Specific values of interest
774 * state == activate_slack
775 * no valid input since the last reset
776 *
777 * state == 0
778 * general operational state
779 *
780 * state == -deactivate_slack
781 * read sufficient empty frames to accept
782 * the end of input and reset
783 */
784
785 if (nd->act_state > 0) { /* Currently inactive */
786 if (value)
787 /*
788 * Consider each live contact as
789 * evidence of intentional activity.
790 */
791 nd->act_state = (nd->act_state > value)
792 ? nd->act_state - value
793 : 0;
794 else
795 /*
796 * Empty frame before we hit the
797 * activity threshold, reset.
798 */
799 nd->act_state = nd->activate_slack;
800
801 /*
802 * Entered this block inactive and no
803 * coordinates sent this frame, so hold off
804 * on button state.
805 */
806 break;
807 } else { /* Currently active */
808 if (value && nd->act_state >=
809 nd->deactivate_slack)
810 /*
811 * Live point: clear accumulated
812 * deactivation count.
813 */
814 nd->act_state = 0;
815 else if (nd->act_state <= nd->deactivate_slack)
816 /*
817 * We've consumed the deactivation
818 * slack, time to deactivate and reset.
819 */
820 nd->act_state =
821 nd->activate_slack;
822 else { /* Move towards deactivation */
823 nd->act_state--;
824 break;
825 }
826 }
827
828 if (nd->first_contact_touch && nd->act_state <= 0) {
829 /*
830 * Check to see if we're ready to start
831 * emitting touch events.
832 *
833 * Note: activation slack will decrease over
834 * the course of the frame, and it will be
835 * inconsistent from the start to the end of
836 * the frame. However if the frame starts
837 * with slack, first_contact_touch will still
838 * be 0 and we will not get to this point.
839 */
840 input_report_key(input, BTN_TOOL_DOUBLETAP, 1);
841 input_report_key(input, BTN_TOUCH, 1);
842 } else {
843 input_report_key(input, BTN_TOOL_DOUBLETAP, 0);
844 input_report_key(input, BTN_TOUCH, 0);
845 }
846 break;
847
848 default:
849 /* fall-back to the generic hidinput handling */
850 return 0;
851 }
852
853not_claimed_input:
854
855 /* we have handled the hidinput part, now remains hiddev */
856 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_hid_event)
857 hid->hiddev_hid_event(hid, field, usage, value);
858
859 return 1;
860}
861
862static int ntrig_input_configured(struct hid_device *hid,
863 struct hid_input *hidinput)
864
865{
866 struct input_dev *input = hidinput->input;
867
868 if (hidinput->report->maxfield < 1)
869 return 0;
870
871 switch (hidinput->report->field[0]->application) {
872 case HID_DG_PEN:
873 input->name = "N-Trig Pen";
874 break;
875 case HID_DG_TOUCHSCREEN:
876 /* These keys are redundant for fingers, clear them
877 * to prevent incorrect identification */
878 __clear_bit(BTN_TOOL_PEN, input->keybit);
879 __clear_bit(BTN_TOOL_FINGER, input->keybit);
880 __clear_bit(BTN_0, input->keybit);
881 __set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
882 /*
883 * The physical touchscreen (single touch)
884 * input has a value for physical, whereas
885 * the multitouch only has logical input
886 * fields.
887 */
888 input->name = (hidinput->report->field[0]->physical) ?
889 "N-Trig Touchscreen" :
890 "N-Trig MultiTouch";
891 break;
892 }
893
894 return 0;
895}
896
897static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
898{
899 int ret;
900 struct ntrig_data *nd;
901 struct hid_report *report;
902
903 if (id->driver_data)
904 hdev->quirks |= HID_QUIRK_MULTI_INPUT
905 | HID_QUIRK_NO_INIT_REPORTS;
906
907 nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL);
908 if (!nd) {
909 hid_err(hdev, "cannot allocate N-Trig data\n");
910 return -ENOMEM;
911 }
912
913 nd->reading_mt = false;
914 nd->min_width = 0;
915 nd->min_height = 0;
916 nd->activate_slack = activate_slack;
917 nd->act_state = activate_slack;
918 nd->deactivate_slack = -deactivate_slack;
919 nd->sensor_logical_width = 1;
920 nd->sensor_logical_height = 1;
921 nd->sensor_physical_width = 1;
922 nd->sensor_physical_height = 1;
923
924 hid_set_drvdata(hdev, nd);
925
926 ret = hid_parse(hdev);
927 if (ret) {
928 hid_err(hdev, "parse failed\n");
929 goto err_free;
930 }
931
932 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
933 if (ret) {
934 hid_err(hdev, "hw start failed\n");
935 goto err_free;
936 }
937
938 /* This is needed for devices with more recent firmware versions */
939 report = hdev->report_enum[HID_FEATURE_REPORT].report_id_hash[0x0a];
940 if (report) {
941 /* Let the device settle to ensure the wakeup message gets
942 * through */
943 hid_hw_wait(hdev);
944 hid_hw_request(hdev, report, HID_REQ_GET_REPORT);
945
946 /*
947 * Sanity check: if the current mode is invalid reset it to
948 * something reasonable.
949 */
950 if (ntrig_get_mode(hdev) >= 4)
951 ntrig_set_mode(hdev, 3);
952 }
953
954 ntrig_report_version(hdev);
955
956 ret = sysfs_create_group(&hdev->dev.kobj,
957 &ntrig_attribute_group);
958 if (ret)
959 hid_err(hdev, "cannot create sysfs group\n");
960
961 return 0;
962err_free:
963 kfree(nd);
964 return ret;
965}
966
967static void ntrig_remove(struct hid_device *hdev)
968{
969 sysfs_remove_group(&hdev->dev.kobj,
970 &ntrig_attribute_group);
971 hid_hw_stop(hdev);
972 kfree(hid_get_drvdata(hdev));
973}
974
975static const struct hid_device_id ntrig_devices[] = {
976 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN),
977 .driver_data = NTRIG_DUPLICATE_USAGES },
978 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_1),
979 .driver_data = NTRIG_DUPLICATE_USAGES },
980 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_2),
981 .driver_data = NTRIG_DUPLICATE_USAGES },
982 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_3),
983 .driver_data = NTRIG_DUPLICATE_USAGES },
984 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_4),
985 .driver_data = NTRIG_DUPLICATE_USAGES },
986 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_5),
987 .driver_data = NTRIG_DUPLICATE_USAGES },
988 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_6),
989 .driver_data = NTRIG_DUPLICATE_USAGES },
990 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_7),
991 .driver_data = NTRIG_DUPLICATE_USAGES },
992 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_8),
993 .driver_data = NTRIG_DUPLICATE_USAGES },
994 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_9),
995 .driver_data = NTRIG_DUPLICATE_USAGES },
996 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_10),
997 .driver_data = NTRIG_DUPLICATE_USAGES },
998 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_11),
999 .driver_data = NTRIG_DUPLICATE_USAGES },
1000 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_12),
1001 .driver_data = NTRIG_DUPLICATE_USAGES },
1002 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_13),
1003 .driver_data = NTRIG_DUPLICATE_USAGES },
1004 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_14),
1005 .driver_data = NTRIG_DUPLICATE_USAGES },
1006 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_15),
1007 .driver_data = NTRIG_DUPLICATE_USAGES },
1008 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_16),
1009 .driver_data = NTRIG_DUPLICATE_USAGES },
1010 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_17),
1011 .driver_data = NTRIG_DUPLICATE_USAGES },
1012 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN_18),
1013 .driver_data = NTRIG_DUPLICATE_USAGES },
1014 { }
1015};
1016MODULE_DEVICE_TABLE(hid, ntrig_devices);
1017
1018static const struct hid_usage_id ntrig_grabbed_usages[] = {
1019 { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
1020 { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1 }
1021};
1022
1023static struct hid_driver ntrig_driver = {
1024 .name = "ntrig",
1025 .id_table = ntrig_devices,
1026 .probe = ntrig_probe,
1027 .remove = ntrig_remove,
1028 .input_mapping = ntrig_input_mapping,
1029 .input_mapped = ntrig_input_mapped,
1030 .input_configured = ntrig_input_configured,
1031 .usage_table = ntrig_grabbed_usages,
1032 .event = ntrig_event,
1033};
1034module_hid_driver(ntrig_driver);
1035
1036MODULE_LICENSE("GPL");
1037