2 * HID driver for N-Trig touchscreens
4 * Copyright (c) 2008 Rafi Rubin
5 * Copyright (c) 2009 Stephane Chatty
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)
16 #include <linux/device.h>
17 #include <linux/hid.h>
18 #include <linux/module.h>
22 #define NTRIG_DUPLICATE_USAGES 0x001
24 #define nt_map_key_clear(c) hid_map_usage_clear(hi, usage, bit, max, \
28 /* Incoming raw values for a single contact */
34 __u8 first_contact_confidence;
41 * this driver is aimed at two firmware versions in circulation:
42 * - dual pen/finger single touch
43 * - finger multitouch, pen not working
46 static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi,
47 struct hid_field *field, struct hid_usage *usage,
48 unsigned long **bit, int *max)
50 /* No special mappings needed for the pen and single touch */
54 switch (usage->hid & HID_USAGE_PAGE) {
58 hid_map_usage(hi, usage, bit, max,
59 EV_ABS, ABS_MT_POSITION_X);
60 input_set_abs_params(hi->input, ABS_X,
61 field->logical_minimum,
62 field->logical_maximum, 0, 0);
65 hid_map_usage(hi, usage, bit, max,
66 EV_ABS, ABS_MT_POSITION_Y);
67 input_set_abs_params(hi->input, ABS_Y,
68 field->logical_minimum,
69 field->logical_maximum, 0, 0);
74 case HID_UP_DIGITIZER:
76 /* we do not want to map these for now */
77 case HID_DG_CONTACTID: /* Not trustworthy, squelch for now */
78 case HID_DG_INPUTMODE:
79 case HID_DG_DEVICEINDEX:
80 case HID_DG_CONTACTMAX:
83 /* width/height mapped on TouchMajor/TouchMinor/Orientation */
85 hid_map_usage(hi, usage, bit, max,
86 EV_ABS, ABS_MT_TOUCH_MAJOR);
89 hid_map_usage(hi, usage, bit, max,
90 EV_ABS, ABS_MT_TOUCH_MINOR);
91 input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
98 /* we do not want to map these: no input-oriented meaning */
105 static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi,
106 struct hid_field *field, struct hid_usage *usage,
107 unsigned long **bit, int *max)
109 /* No special mappings needed for the pen and single touch */
113 if (usage->type == EV_KEY || usage->type == EV_REL
114 || usage->type == EV_ABS)
115 clear_bit(usage->code, *bit);
121 * this function is called upon all reports
122 * so that we can filter contact point information,
123 * decide whether we are in multi or single touch mode
124 * and call input_mt_sync after each point if necessary
126 static int ntrig_event (struct hid_device *hid, struct hid_field *field,
127 struct hid_usage *usage, __s32 value)
129 struct input_dev *input = field->hidinput->input;
130 struct ntrig_data *nd = hid_get_drvdata(hid);
132 /* No special handling needed for the pen */
133 if (field->application == HID_DG_PEN)
136 if (hid->claimed & HID_CLAIMED_INPUT) {
137 switch (usage->hid) {
139 /* Tag indicating the start of a multitouch group */
141 nd->first_contact_confidence = 0;
143 case HID_DG_TIPSWITCH:
144 /* Prevent emission of touch until validated */
146 case HID_DG_CONFIDENCE:
147 nd->confidence = value;
151 /* Clear the contact footer */
152 nd->mt_foot_count = 0;
157 case HID_DG_CONTACTID:
166 * when in single touch mode, this is the last
167 * report received in a finger event. We want
168 * to emit a normal (X, Y) position
170 if (!nd->reading_mt) {
171 input_report_key(input, BTN_TOOL_DOUBLETAP,
172 (nd->confidence != 0));
173 input_event(input, EV_ABS, ABS_X, nd->x);
174 input_event(input, EV_ABS, ABS_Y, nd->y);
179 * we receive this when the device is in multitouch
180 * mode. The first of the three values tagged with
181 * this usage tells if the contact point is real
185 /* Shouldn't get more than 4 footer packets, so skip */
186 if (nd->mt_foot_count >= 4)
189 nd->mt_footer[nd->mt_foot_count++] = value;
191 /* if the footer isn't complete break */
192 if (nd->mt_foot_count != 4)
195 /* Pen activity signal, trigger end of touch. */
196 if (nd->mt_footer[2]) {
201 /* If the contact was invalid */
202 if (!(nd->confidence && nd->mt_footer[0])
209 /* emit a normal (X, Y) for the first point only */
211 nd->first_contact_confidence = nd->confidence;
212 input_event(input, EV_ABS, ABS_X, nd->x);
213 input_event(input, EV_ABS, ABS_Y, nd->y);
215 input_event(input, EV_ABS, ABS_MT_POSITION_X, nd->x);
216 input_event(input, EV_ABS, ABS_MT_POSITION_Y, nd->y);
218 input_event(input, EV_ABS,
219 ABS_MT_ORIENTATION, 1);
220 input_event(input, EV_ABS,
221 ABS_MT_TOUCH_MAJOR, nd->w);
222 input_event(input, EV_ABS,
223 ABS_MT_TOUCH_MINOR, nd->h);
225 input_event(input, EV_ABS,
226 ABS_MT_ORIENTATION, 0);
227 input_event(input, EV_ABS,
228 ABS_MT_TOUCH_MAJOR, nd->h);
229 input_event(input, EV_ABS,
230 ABS_MT_TOUCH_MINOR, nd->w);
232 input_mt_sync(field->hidinput->input);
235 case HID_DG_CONTACTCOUNT: /* End of a multitouch group */
241 if (nd->first_contact_confidence) {
243 case 0: /* for single touch devices */
245 input_report_key(input,
246 BTN_TOOL_DOUBLETAP, 1);
249 input_report_key(input,
250 BTN_TOOL_TRIPLETAP, 1);
254 input_report_key(input,
255 BTN_TOOL_QUADTAP, 1);
257 input_report_key(input, BTN_TOUCH, 1);
259 input_report_key(input,
260 BTN_TOOL_DOUBLETAP, 0);
261 input_report_key(input,
262 BTN_TOOL_TRIPLETAP, 0);
263 input_report_key(input,
264 BTN_TOOL_QUADTAP, 0);
265 input_report_key(input, BTN_TOUCH, 0);
270 /* fallback to the generic hidinput handling */
275 /* we have handled the hidinput part, now remains hiddev */
276 if ((hid->claimed & HID_CLAIMED_HIDDEV) && hid->hiddev_hid_event)
277 hid->hiddev_hid_event(hid, field, usage, value);
282 static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
285 struct ntrig_data *nd;
286 struct hid_input *hidinput;
287 struct input_dev *input;
290 hdev->quirks |= HID_QUIRK_MULTI_INPUT;
292 nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL);
294 dev_err(&hdev->dev, "cannot allocate N-Trig data\n");
299 hid_set_drvdata(hdev, nd);
301 ret = hid_parse(hdev);
303 dev_err(&hdev->dev, "parse failed\n");
307 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT & ~HID_CONNECT_FF);
309 dev_err(&hdev->dev, "hw start failed\n");
314 list_for_each_entry(hidinput, &hdev->inputs, list) {
315 if (hidinput->report->maxfield < 1)
318 input = hidinput->input;
319 switch (hidinput->report->field[0]->application) {
321 input->name = "N-Trig Pen";
323 case HID_DG_TOUCHSCREEN:
324 /* These keys are redundant for fingers, clear them
325 * to prevent incorrect identification */
326 __clear_bit(BTN_TOOL_PEN, input->keybit);
327 __clear_bit(BTN_TOOL_FINGER, input->keybit);
328 __clear_bit(BTN_0, input->keybit);
330 * A little something special to enable
331 * two and three finger taps.
333 __set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
334 __set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
335 __set_bit(BTN_TOOL_QUADTAP, input->keybit);
337 * The physical touchscreen (single touch)
338 * input has a value for physical, whereas
339 * the multitouch only has logical input
343 (hidinput->report->field[0]
345 "N-Trig Touchscreen" :
357 static void ntrig_remove(struct hid_device *hdev)
360 kfree(hid_get_drvdata(hdev));
363 static const struct hid_device_id ntrig_devices[] = {
364 { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN),
365 .driver_data = NTRIG_DUPLICATE_USAGES },
368 MODULE_DEVICE_TABLE(hid, ntrig_devices);
370 static const struct hid_usage_id ntrig_grabbed_usages[] = {
371 { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
372 { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1 }
375 static struct hid_driver ntrig_driver = {
377 .id_table = ntrig_devices,
378 .probe = ntrig_probe,
379 .remove = ntrig_remove,
380 .input_mapping = ntrig_input_mapping,
381 .input_mapped = ntrig_input_mapped,
382 .usage_table = ntrig_grabbed_usages,
383 .event = ntrig_event,
386 static int __init ntrig_init(void)
388 return hid_register_driver(&ntrig_driver);
391 static void __exit ntrig_exit(void)
393 hid_unregister_driver(&ntrig_driver);
396 module_init(ntrig_init);
397 module_exit(ntrig_exit);
398 MODULE_LICENSE("GPL");