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