tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1/*
2 * HID driver for 3M PCT multitouch panels
3 *
4 * Copyright (c) 2009-2010 Stephane Chatty <chatty@enac.fr>
5 * Copyright (c) 2010 Henrik Rydberg <rydberg@euromail.se>
6 * Copyright (c) 2010 Canonical, Ltd.
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
23MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
24MODULE_DESCRIPTION("3M PCT multitouch panels");
25MODULE_LICENSE("GPL");
26
27#include "hid-ids.h"
28
29#define MAX_SLOTS 60
30#define MAX_TRKID USHRT_MAX
31#define MAX_EVENTS 360
32
33/* estimated signal-to-noise ratios */
34#define SN_MOVE 2048
35#define SN_WIDTH 128
36
37struct mmm_finger {
38 __s32 x, y, w, h;
39 __u16 id;
40 bool prev_touch;
41 bool touch, valid;
42};
43
44struct mmm_data {
45 struct mmm_finger f[MAX_SLOTS];
46 __u16 id;
47 __u8 curid;
48 __u8 nexp, nreal;
49 bool touch, valid;
50};
51
52static int mmm_input_mapping(struct hid_device *hdev, struct hid_input *hi,
53 struct hid_field *field, struct hid_usage *usage,
54 unsigned long **bit, int *max)
55{
56 int f1 = field->logical_minimum;
57 int f2 = field->logical_maximum;
58 int df = f2 - f1;
59
60 switch (usage->hid & HID_USAGE_PAGE) {
61
62 case HID_UP_BUTTON:
63 return -1;
64
65 case HID_UP_GENDESK:
66 switch (usage->hid) {
67 case HID_GD_X:
68 hid_map_usage(hi, usage, bit, max,
69 EV_ABS, ABS_MT_POSITION_X);
70 input_set_abs_params(hi->input, ABS_MT_POSITION_X,
71 f1, f2, df / SN_MOVE, 0);
72 /* touchscreen emulation */
73 input_set_abs_params(hi->input, ABS_X,
74 f1, f2, df / SN_MOVE, 0);
75 return 1;
76 case HID_GD_Y:
77 hid_map_usage(hi, usage, bit, max,
78 EV_ABS, ABS_MT_POSITION_Y);
79 input_set_abs_params(hi->input, ABS_MT_POSITION_Y,
80 f1, f2, df / SN_MOVE, 0);
81 /* touchscreen emulation */
82 input_set_abs_params(hi->input, ABS_Y,
83 f1, f2, df / SN_MOVE, 0);
84 return 1;
85 }
86 return 0;
87
88 case HID_UP_DIGITIZER:
89 switch (usage->hid) {
90 /* we do not want to map these: no input-oriented meaning */
91 case 0x14:
92 case 0x23:
93 case HID_DG_INPUTMODE:
94 case HID_DG_DEVICEINDEX:
95 case HID_DG_CONTACTCOUNT:
96 case HID_DG_CONTACTMAX:
97 case HID_DG_INRANGE:
98 case HID_DG_CONFIDENCE:
99 return -1;
100 case HID_DG_TIPSWITCH:
101 /* touchscreen emulation */
102 hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH);
103 input_set_capability(hi->input, EV_KEY, BTN_TOUCH);
104 return 1;
105 case HID_DG_WIDTH:
106 hid_map_usage(hi, usage, bit, max,
107 EV_ABS, ABS_MT_TOUCH_MAJOR);
108 input_set_abs_params(hi->input, ABS_MT_TOUCH_MAJOR,
109 f1, f2, df / SN_WIDTH, 0);
110 return 1;
111 case HID_DG_HEIGHT:
112 hid_map_usage(hi, usage, bit, max,
113 EV_ABS, ABS_MT_TOUCH_MINOR);
114 input_set_abs_params(hi->input, ABS_MT_TOUCH_MINOR,
115 f1, f2, df / SN_WIDTH, 0);
116 input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
117 0, 1, 0, 0);
118 return 1;
119 case HID_DG_CONTACTID:
120 field->logical_maximum = MAX_TRKID;
121 hid_map_usage(hi, usage, bit, max,
122 EV_ABS, ABS_MT_TRACKING_ID);
123 input_set_abs_params(hi->input, ABS_MT_TRACKING_ID,
124 0, MAX_TRKID, 0, 0);
125 if (!hi->input->mt)
126 input_mt_create_slots(hi->input, MAX_SLOTS);
127 input_set_events_per_packet(hi->input, MAX_EVENTS);
128 return 1;
129 }
130 /* let hid-input decide for the others */
131 return 0;
132
133 case 0xff000000:
134 /* we do not want to map these: no input-oriented meaning */
135 return -1;
136 }
137
138 return 0;
139}
140
141static int mmm_input_mapped(struct hid_device *hdev, struct hid_input *hi,
142 struct hid_field *field, struct hid_usage *usage,
143 unsigned long **bit, int *max)
144{
145 /* tell hid-input to skip setup of these event types */
146 if (usage->type == EV_KEY || usage->type == EV_ABS)
147 set_bit(usage->type, hi->input->evbit);
148 return -1;
149}
150
151/*
152 * this function is called when a whole packet has been received and processed,
153 * so that it can decide what to send to the input layer.
154 */
155static void mmm_filter_event(struct mmm_data *md, struct input_dev *input)
156{
157 struct mmm_finger *oldest = 0;
158 int i;
159 for (i = 0; i < MAX_SLOTS; ++i) {
160 struct mmm_finger *f = &md->f[i];
161 if (!f->valid) {
162 /* this finger is just placeholder data, ignore */
163 continue;
164 }
165 input_mt_slot(input, i);
166 if (f->touch) {
167 /* this finger is on the screen */
168 int wide = (f->w > f->h);
169 /* divided by two to match visual scale of touch */
170 int major = max(f->w, f->h) >> 1;
171 int minor = min(f->w, f->h) >> 1;
172
173 if (!f->prev_touch)
174 f->id = md->id++;
175 input_event(input, EV_ABS, ABS_MT_TRACKING_ID, f->id);
176 input_event(input, EV_ABS, ABS_MT_POSITION_X, f->x);
177 input_event(input, EV_ABS, ABS_MT_POSITION_Y, f->y);
178 input_event(input, EV_ABS, ABS_MT_ORIENTATION, wide);
179 input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, major);
180 input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, minor);
181 /* touchscreen emulation: pick the oldest contact */
182 if (!oldest || ((f->id - oldest->id) & (SHRT_MAX + 1)))
183 oldest = f;
184 } else {
185 /* this finger took off the screen */
186 input_event(input, EV_ABS, ABS_MT_TRACKING_ID, -1);
187 }
188 f->prev_touch = f->touch;
189 f->valid = 0;
190 }
191
192 /* touchscreen emulation */
193 if (oldest) {
194 input_event(input, EV_KEY, BTN_TOUCH, 1);
195 input_event(input, EV_ABS, ABS_X, oldest->x);
196 input_event(input, EV_ABS, ABS_Y, oldest->y);
197 } else {
198 input_event(input, EV_KEY, BTN_TOUCH, 0);
199 }
200 input_sync(input);
201}
202
203/*
204 * this function is called upon all reports
205 * so that we can accumulate contact point information,
206 * and call input_mt_sync after each point.
207 */
208static int mmm_event(struct hid_device *hid, struct hid_field *field,
209 struct hid_usage *usage, __s32 value)
210{
211 struct mmm_data *md = hid_get_drvdata(hid);
212 /*
213 * strangely, this function can be called before
214 * field->hidinput is initialized!
215 */
216 if (hid->claimed & HID_CLAIMED_INPUT) {
217 struct input_dev *input = field->hidinput->input;
218 switch (usage->hid) {
219 case HID_DG_TIPSWITCH:
220 md->touch = value;
221 break;
222 case HID_DG_CONFIDENCE:
223 md->valid = value;
224 break;
225 case HID_DG_WIDTH:
226 if (md->valid)
227 md->f[md->curid].w = value;
228 break;
229 case HID_DG_HEIGHT:
230 if (md->valid)
231 md->f[md->curid].h = value;
232 break;
233 case HID_DG_CONTACTID:
234 value = clamp_val(value, 0, MAX_SLOTS - 1);
235 if (md->valid) {
236 md->curid = value;
237 md->f[value].touch = md->touch;
238 md->f[value].valid = 1;
239 md->nreal++;
240 }
241 break;
242 case HID_GD_X:
243 if (md->valid)
244 md->f[md->curid].x = value;
245 break;
246 case HID_GD_Y:
247 if (md->valid)
248 md->f[md->curid].y = value;
249 break;
250 case HID_DG_CONTACTCOUNT:
251 if (value)
252 md->nexp = value;
253 if (md->nreal >= md->nexp) {
254 mmm_filter_event(md, input);
255 md->nreal = 0;
256 }
257 break;
258 }
259 }
260
261 /* we have handled the hidinput part, now remains hiddev */
262 if (hid->claimed & HID_CLAIMED_HIDDEV && hid->hiddev_hid_event)
263 hid->hiddev_hid_event(hid, field, usage, value);
264
265 return 1;
266}
267
268static int mmm_probe(struct hid_device *hdev, const struct hid_device_id *id)
269{
270 int ret;
271 struct mmm_data *md;
272
273 hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC;
274
275 md = kzalloc(sizeof(struct mmm_data), GFP_KERNEL);
276 if (!md) {
277 dev_err(&hdev->dev, "cannot allocate 3M data\n");
278 return -ENOMEM;
279 }
280 hid_set_drvdata(hdev, md);
281
282 ret = hid_parse(hdev);
283 if (!ret)
284 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
285
286 if (ret)
287 kfree(md);
288 return ret;
289}
290
291static void mmm_remove(struct hid_device *hdev)
292{
293 hid_hw_stop(hdev);
294 kfree(hid_get_drvdata(hdev));
295 hid_set_drvdata(hdev, NULL);
296}
297
298static const struct hid_device_id mmm_devices[] = {
299 { HID_USB_DEVICE(USB_VENDOR_ID_3M, USB_DEVICE_ID_3M1968) },
300 { HID_USB_DEVICE(USB_VENDOR_ID_3M, USB_DEVICE_ID_3M2256) },
301 { }
302};
303MODULE_DEVICE_TABLE(hid, mmm_devices);
304
305static const struct hid_usage_id mmm_grabbed_usages[] = {
306 { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
307 { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
308};
309
310static struct hid_driver mmm_driver = {
311 .name = "3m-pct",
312 .id_table = mmm_devices,
313 .probe = mmm_probe,
314 .remove = mmm_remove,
315 .input_mapping = mmm_input_mapping,
316 .input_mapped = mmm_input_mapped,
317 .usage_table = mmm_grabbed_usages,
318 .event = mmm_event,
319};
320
321static int __init mmm_init(void)
322{
323 return hid_register_driver(&mmm_driver);
324}
325
326static void __exit mmm_exit(void)
327{
328 hid_unregister_driver(&mmm_driver);
329}
330
331module_init(mmm_init);
332module_exit(mmm_exit);
333