2 * HID driver for 3M PCT multitouch panels
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.
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)
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>
23 MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
24 MODULE_DESCRIPTION("3M PCT multitouch panels");
25 MODULE_LICENSE("GPL");
30 #define MAX_TRKID USHRT_MAX
31 #define MAX_EVENTS 360
33 /* estimated signal-to-noise ratios */
45 struct mmm_finger f[MAX_SLOTS];
52 static 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)
56 int f1 = field->logical_minimum;
57 int f2 = field->logical_maximum;
60 switch (usage->hid & HID_USAGE_PAGE) {
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);
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);
88 case HID_UP_DIGITIZER:
90 /* we do not want to map these: no input-oriented meaning */
93 case HID_DG_INPUTMODE:
94 case HID_DG_DEVICEINDEX:
95 case HID_DG_CONTACTCOUNT:
96 case HID_DG_CONTACTMAX:
98 case HID_DG_CONFIDENCE:
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);
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);
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,
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,
126 input_mt_create_slots(hi->input, MAX_SLOTS);
127 input_set_events_per_packet(hi->input, MAX_EVENTS);
130 /* let hid-input decide for the others */
134 /* we do not want to map these: no input-oriented meaning */
141 static 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)
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);
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.
155 static void mmm_filter_event(struct mmm_data *md, struct input_dev *input)
157 struct mmm_finger *oldest = 0;
159 for (i = 0; i < MAX_SLOTS; ++i) {
160 struct mmm_finger *f = &md->f[i];
162 /* this finger is just placeholder data, ignore */
165 input_mt_slot(input, i);
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;
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)))
185 /* this finger took off the screen */
186 input_event(input, EV_ABS, ABS_MT_TRACKING_ID, -1);
188 f->prev_touch = f->touch;
192 /* touchscreen emulation */
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);
198 input_event(input, EV_KEY, BTN_TOUCH, 0);
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.
208 static int mmm_event(struct hid_device *hid, struct hid_field *field,
209 struct hid_usage *usage, __s32 value)
211 struct mmm_data *md = hid_get_drvdata(hid);
213 * strangely, this function can be called before
214 * field->hidinput is initialized!
216 if (hid->claimed & HID_CLAIMED_INPUT) {
217 struct input_dev *input = field->hidinput->input;
218 switch (usage->hid) {
219 case HID_DG_TIPSWITCH:
222 case HID_DG_CONFIDENCE:
227 md->f[md->curid].w = value;
231 md->f[md->curid].h = value;
233 case HID_DG_CONTACTID:
234 value = clamp_val(value, 0, MAX_SLOTS - 1);
237 md->f[value].touch = md->touch;
238 md->f[value].valid = 1;
244 md->f[md->curid].x = value;
248 md->f[md->curid].y = value;
250 case HID_DG_CONTACTCOUNT:
253 if (md->nreal >= md->nexp) {
254 mmm_filter_event(md, input);
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);
268 static int mmm_probe(struct hid_device *hdev, const struct hid_device_id *id)
273 hdev->quirks |= HID_QUIRK_NO_INPUT_SYNC;
275 md = kzalloc(sizeof(struct mmm_data), GFP_KERNEL);
277 dev_err(&hdev->dev, "cannot allocate 3M data\n");
280 hid_set_drvdata(hdev, md);
282 ret = hid_parse(hdev);
284 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
291 static void mmm_remove(struct hid_device *hdev)
294 kfree(hid_get_drvdata(hdev));
295 hid_set_drvdata(hdev, NULL);
298 static 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) },
303 MODULE_DEVICE_TABLE(hid, mmm_devices);
305 static 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}
310 static struct hid_driver mmm_driver = {
312 .id_table = mmm_devices,
314 .remove = mmm_remove,
315 .input_mapping = mmm_input_mapping,
316 .input_mapped = mmm_input_mapped,
317 .usage_table = mmm_grabbed_usages,
321 static int __init mmm_init(void)
323 return hid_register_driver(&mmm_driver);
326 static void __exit mmm_exit(void)
328 hid_unregister_driver(&mmm_driver);
331 module_init(mmm_init);
332 module_exit(mmm_exit);