aboutsummaryrefslogtreecommitdiff
path: root/drivers/hid/hid-3m-pct.c
blob: 39628e02a4288f290211ab8de753f8af0a67210e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
/*
 *  HID driver for 3M PCT multitouch panels
 *
 *  Copyright (c) 2009-2010 Stephane Chatty <chatty@enac.fr>
 *  Copyright (c) 2010      Henrik Rydberg <rydberg@euromail.se>
 *  Copyright (c) 2010      Canonical, Ltd.
 *
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 */

#include <linux/device.h>
#include <linux/hid.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb.h>

MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
MODULE_DESCRIPTION("3M PCT multitouch panels");
MODULE_LICENSE("GPL");

#include "hid-ids.h"

#define MAX_SLOTS		60
#define MAX_TRKID		USHRT_MAX
#define MAX_EVENTS		360

/* estimated signal-to-noise ratios */
#define SN_MOVE			2048
#define SN_WIDTH		128

struct mmm_finger {
	__s32 x, y, w, h;
	__u16 id;
	bool prev_touch;
	bool touch, valid;
};

struct mmm_data {
	struct mmm_finger f[MAX_SLOTS];
	__u16 id;
	__u8 curid;
	__u8 nexp, nreal;
	bool touch, valid;
};

static int mmm_input_mapping(struct hid_device *hdev, struct hid_input *hi,
		struct hid_field *field, struct hid_usage *usage,
		unsigned long **bit, int *max)
{
	int f1 = field->logical_minimum;
	int f2 = field->logical_maximum;
	int df = f2 - f1;

	switch (usage->hid & HID_USAGE_PAGE) {

	case HID_UP_BUTTON:
		return -1;

	case HID_UP_GENDESK:
		switch (usage->hid) {
		case HID_GD_X:
			hid_map_usage(hi, usage, bit, max,
					EV_ABS, ABS_MT_POSITION_X);
			input_set_abs_params(hi->input, ABS_MT_POSITION_X,
					     f1, f2, df / SN_MOVE, 0);
			/* touchscreen emulation */
			input_set_abs_params(hi->input, ABS_X,
					     f1, f2, df / SN_MOVE, 0);
			return 1;
		case HID_GD_Y:
			hid_map_usage(hi, usage, bit, max,
					EV_ABS, ABS_MT_POSITION_Y);
			input_set_abs_params(hi->input, ABS_MT_POSITION_Y,
					     f1, f2, df / SN_MOVE, 0);
			/* touchscreen emulation */
			input_set_abs_params(hi->input, ABS_Y,
					     f1, f2, df / SN_MOVE, 0);
			return 1;
		}
		return 0;

	case HID_UP_DIGITIZER:
		switch (usage->hid) {
		/* we do not want to map these: no input-oriented meaning */
		case 0x14:
		case 0x23:
		case HID_DG_INPUTMODE:
		case HID_DG_DEVICEINDEX:
		case HID_DG_CONTACTCOUNT:
		case HID_DG_CONTACTMAX:
		case HID_DG_INRANGE:
		case HID_DG_CONFIDENCE:
			return -1;
		case HID_DG_TIPSWITCH:
			/* touchscreen emulation */
			hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH);
			input_set_capability(hi->input, EV_KEY, BTN_TOUCH);
			return 1;
		case HID_DG_WIDTH:
			hid_map_usage(hi, usage, bit, max,
					EV_ABS, ABS_MT_TOUCH_MAJOR);
			input_set_abs_params(hi->input, ABS_MT_TOUCH_MAJOR,
					     f1, f2, df / SN_WIDTH, 0);
			return 1;
		case HID_DG_HEIGHT:
			hid_map_usage(hi, usage, bit, max,
					EV_ABS, ABS_MT_TOUCH_MINOR);
			input_set_abs_params(hi->input, ABS_MT_TOUCH_MINOR,
					     f1, f2, df / SN_WIDTH, 0);
			input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
					0, 1, 0, 0);
			return 1;
		case HID_DG_CONTACTID:
			field->logical_maximum = MAX_TRKID;
			hid_map_usage(hi, usage, bit, max,
					EV_ABS, ABS_MT_TRACKING_ID);
			input_set_abs_params(hi->input, ABS_MT_TRACKING_ID,
					     0, MAX_TRKID, 0, 0);
			if (!hi->input->mt)
				input_mt_create_slots(hi->input, MAX_SLOTS);
			input_set_events_per_packet(hi->input, MAX_EVENTS);
			return 1;
		}
		/* let hid-input decide for the others */
		return 0;

	case 0xff000000:
		/* we do not want to map these: no input-oriented meaning */
		return -1;
	}

	return 0;
}

static int mmm_input_mapped(struct hid_device *hdev, struct hid_input *hi,
		struct hid_field *field, struct hid_usage *usage,
		unsigned long **bit, int *max)
{
	/* tell hid-input to skip setup of these event types */
	if (usage->type == EV_KEY || usage->type == EV_ABS)
		set_bit(usage->type, hi->input->evbit);
	return -1;
}

/*
 * this function is called when a whole packet has been received and processed,
 * so that it can decide what to send to the input layer.
 */
static void mmm_filter_event(struct mmm_data *md, struct input_dev *input)
{
	struct mmm_finger *oldest = 0;
	int i;
	for (i = 0; i < MAX_SLOTS; ++i) {
		struct mmm_finger *f = &md->f[i];
		if (!f->valid) {
			/* this finger is just placeholder data, ignore */
			continue;
		}
		input_mt_slot(input, i);
		if (f->touch) {
			/* this finger is on the screen */
			int wide = (f->w > f->h);
			if (!f->prev_touch)
				f->id = md->id++;
			input_event(input, EV_ABS, ABS_MT_TRACKING_ID, f->id);
			input_event(input, EV_ABS, ABS_MT_POSITION_X, f->x);
			input_event(input, EV_ABS, ABS_MT_POSITION_Y, f->y);
			input_event(input, EV_ABS, ABS_MT_ORIENTATION, wide);
			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR,
						wide ? f->w : f->h);
			input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR,
						wide ? f->h : f->w);
			/* touchscreen emulation: pick the oldest contact */
			if (!oldest || ((f->id - oldest->id) & (SHRT_MAX + 1)))
				oldest = f;
		} else {
			/* this finger took off the screen */
			input_event(input, EV_ABS, ABS_MT_TRACKING_ID, -1);
		}
		f->prev_touch = f->touch;
		f->valid = 0;
	}

	/* touchscreen emulation */
	if (oldest) {
		input_event(input, EV_KEY, BTN_TOUCH, 1);
		input_event(input, EV_ABS, ABS_X, oldest->x);
		input_event(input, EV_ABS, ABS_Y, oldest->y);
	} else {
		input_event(input, EV_KEY, BTN_TOUCH, 0);
	}
	input_sync(input);
}

/*
 * this function is called upon all reports
 * so that we can accumulate contact point information,
 * and call input_mt_sync after each point.
 */
static int mmm_event(struct hid_device *hid, struct hid_field *field,
				struct hid_usage *usage, __s32 value)
{
	struct mmm_data *md = hid_get_drvdata(hid);
	/*
	 * strangely, this function can be called before
	 * field->hidinput is initialized!
	 */
	if (hid->claimed & HID_CLAIMED_INPUT) {
		struct input_dev *input = field->hidinput->input;
		switch (usage->hid) {
		case HID_DG_TIPSWITCH:
			md->touch = value;
			break;
		case HID_DG_CONFIDENCE:
			md->valid = value;
			break;
		case HID_DG_WIDTH:
			if (md->valid)
				md->f[md->curid].w = value;
			break;
		case HID_DG_HEIGHT:
			if (md->valid)
				md->f[md->curid].h = value;
			break;
		case HID_DG_CONTACTID:
			value = clamp_val(value, 0, MAX_SLOTS - 1);
			if (md->valid) {
				md->curid = value;
				md->f[value].touch = md->touch;
				md->f[value].valid = 1;
				md->nreal++;
			}
			break;
		case HID_GD_X:
			if (md->valid)
				md->f[md->curid].x = value;
			break;
		case HID_GD_Y:
			if (md->valid)
				md->f[md->curid].y = value;
			break;
		case HID_DG_CONTACTCOUNT:
			if (value)
				md->nexp = value;
			if (md->nreal >= md->nexp) {
				mmm_filter_event(md, input);
				md->nreal = 0;
			}
			break;
		}
	}

	/* we have handled the hidinput part, now remains hiddev */
	if (hid->claimed & HID_CLAIMED_HIDDEV && hid->hiddev_hid_event)
		hid->hiddev_hid_event(hid, field, usage, value);

	return 1;
}

static int mmm_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
	int ret;
	struct mmm_data *md;

	hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC;

	md = kzalloc(sizeof(struct mmm_data), GFP_KERNEL);
	if (!md) {
		dev_err(&hdev->dev, "cannot allocate 3M data\n");
		return -ENOMEM;
	}
	hid_set_drvdata(hdev, md);

	ret = hid_parse(hdev);
	if (!ret)
		ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);

	if (ret)
		kfree(md);
	return ret;
}

static void mmm_remove(struct hid_device *hdev)
{
	hid_hw_stop(hdev);
	kfree(hid_get_drvdata(hdev));
	hid_set_drvdata(hdev, NULL);
}

static const struct hid_device_id mmm_devices[] = {
	{ HID_USB_DEVICE(USB_VENDOR_ID_3M, USB_DEVICE_ID_3M1968) },
	{ HID_USB_DEVICE(USB_VENDOR_ID_3M, USB_DEVICE_ID_3M2256) },
	{ }
};
MODULE_DEVICE_TABLE(hid, mmm_devices);

static const struct hid_usage_id mmm_grabbed_usages[] = {
	{ HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
	{ HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
};

static struct hid_driver mmm_driver = {
	.name = "3m-pct",
	.id_table = mmm_devices,
	.probe = mmm_probe,
	.remove = mmm_remove,
	.input_mapping = mmm_input_mapping,
	.input_mapped = mmm_input_mapped,
	.usage_table = mmm_grabbed_usages,
	.event = mmm_event,
};

static int __init mmm_init(void)
{
	return hid_register_driver(&mmm_driver);
}

static void __exit mmm_exit(void)
{
	hid_unregister_driver(&mmm_driver);
}

module_init(mmm_init);
module_exit(mmm_exit);