xref: /openbmc/linux/drivers/hid/hid-ntrig.c (revision e8e0929d)
1 /*
2  *  HID driver for N-Trig touchscreens
3  *
4  *  Copyright (c) 2008 Rafi Rubin
5  *  Copyright (c) 2009 Stephane Chatty
6  *
7  */
8 
9 /*
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)
13  * any later version.
14  */
15 
16 #include <linux/device.h>
17 #include <linux/hid.h>
18 #include <linux/module.h>
19 
20 #include "hid-ids.h"
21 
22 #define NTRIG_DUPLICATE_USAGES	0x001
23 
24 #define nt_map_key_clear(c)	hid_map_usage_clear(hi, usage, bit, max, \
25 					EV_KEY, (c))
26 
27 struct ntrig_data {
28 	__s32 x, y, id, w, h;
29 	char reading_a_point, found_contact_id;
30 	char pen_active;
31 	char finger_active;
32 	char inverted;
33 };
34 
35 /*
36  * this driver is aimed at two firmware versions in circulation:
37  *  - dual pen/finger single touch
38  *  - finger multitouch, pen not working
39  */
40 
41 static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi,
42 		struct hid_field *field, struct hid_usage *usage,
43 		unsigned long **bit, int *max)
44 {
45 	switch (usage->hid & HID_USAGE_PAGE) {
46 
47 	case HID_UP_GENDESK:
48 		switch (usage->hid) {
49 		case HID_GD_X:
50 			hid_map_usage(hi, usage, bit, max,
51 					EV_ABS, ABS_MT_POSITION_X);
52 			input_set_abs_params(hi->input, ABS_X,
53 					field->logical_minimum,
54 					field->logical_maximum, 0, 0);
55 			return 1;
56 		case HID_GD_Y:
57 			hid_map_usage(hi, usage, bit, max,
58 					EV_ABS, ABS_MT_POSITION_Y);
59 			input_set_abs_params(hi->input, ABS_Y,
60 					field->logical_minimum,
61 					field->logical_maximum, 0, 0);
62 			return 1;
63 		}
64 		return 0;
65 
66 	case HID_UP_DIGITIZER:
67 		switch (usage->hid) {
68 		/* we do not want to map these for now */
69 		case HID_DG_CONTACTID: /* value is useless */
70 		case HID_DG_INPUTMODE:
71 		case HID_DG_DEVICEINDEX:
72 		case HID_DG_CONTACTCOUNT:
73 		case HID_DG_CONTACTMAX:
74 			return -1;
75 
76 		/* original mapping by Rafi Rubin */
77 		case HID_DG_CONFIDENCE:
78 			nt_map_key_clear(BTN_TOOL_DOUBLETAP);
79 			return 1;
80 
81 		/* width/height mapped on TouchMajor/TouchMinor/Orientation */
82 		case HID_DG_WIDTH:
83 			hid_map_usage(hi, usage, bit, max,
84 					EV_ABS, ABS_MT_TOUCH_MAJOR);
85 			return 1;
86 		case HID_DG_HEIGHT:
87 			hid_map_usage(hi, usage, bit, max,
88 					EV_ABS, ABS_MT_TOUCH_MINOR);
89 			input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
90 					0, 1, 0, 0);
91 			return 1;
92 		}
93 		return 0;
94 
95 	case 0xff000000:
96 		/* we do not want to map these: no input-oriented meaning */
97 		return -1;
98 	}
99 
100 	return 0;
101 }
102 
103 static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi,
104 		struct hid_field *field, struct hid_usage *usage,
105 		unsigned long **bit, int *max)
106 {
107 	if (usage->type == EV_KEY || usage->type == EV_REL
108 			|| usage->type == EV_ABS)
109 		clear_bit(usage->code, *bit);
110 
111 	return 0;
112 }
113 
114 /*
115  * this function is called upon all reports
116  * so that we can filter contact point information,
117  * decide whether we are in multi or single touch mode
118  * and call input_mt_sync after each point if necessary
119  */
120 static int ntrig_event (struct hid_device *hid, struct hid_field *field,
121 		                        struct hid_usage *usage, __s32 value)
122 {
123 	struct input_dev *input = field->hidinput->input;
124 	struct ntrig_data *nd = hid_get_drvdata(hid);
125 
126         if (hid->claimed & HID_CLAIMED_INPUT) {
127 		switch (usage->hid) {
128 
129 		case HID_DG_INRANGE:
130 			if (field->application & 0x3)
131 				nd->pen_active = (value != 0);
132 			else
133 				nd->finger_active = (value != 0);
134 			return 0;
135 
136 		case HID_DG_INVERT:
137 			nd->inverted = value;
138 			return 0;
139 
140 		case HID_GD_X:
141 			nd->x = value;
142 			nd->reading_a_point = 1;
143 			break;
144 		case HID_GD_Y:
145 			nd->y = value;
146 			break;
147 		case HID_DG_CONTACTID:
148 			nd->id = value;
149 			/* we receive this only when in multitouch mode */
150 			nd->found_contact_id = 1;
151 			break;
152 		case HID_DG_WIDTH:
153 			nd->w = value;
154 			break;
155 		case HID_DG_HEIGHT:
156 			nd->h = value;
157 			/*
158 			 * when in single touch mode, this is the last
159 			 * report received in a finger event. We want
160 			 * to emit a normal (X, Y) position
161 			 */
162 			if (!nd->found_contact_id) {
163 				if (nd->pen_active && nd->finger_active) {
164 					input_report_key(input, BTN_TOOL_DOUBLETAP, 0);
165 					input_report_key(input, BTN_TOOL_DOUBLETAP, 1);
166 				}
167 				input_event(input, EV_ABS, ABS_X, nd->x);
168 				input_event(input, EV_ABS, ABS_Y, nd->y);
169 			}
170 			break;
171 		case HID_DG_TIPPRESSURE:
172 			/*
173 			 * when in single touch mode, this is the last
174 			 * report received in a pen event. We want
175 			 * to emit a normal (X, Y) position
176 			 */
177 			if (! nd->found_contact_id) {
178 				if (nd->pen_active && nd->finger_active) {
179 					input_report_key(input,
180 							nd->inverted ? BTN_TOOL_RUBBER : BTN_TOOL_PEN
181 							, 0);
182 					input_report_key(input,
183 							nd->inverted ? BTN_TOOL_RUBBER : BTN_TOOL_PEN
184 							, 1);
185 				}
186 				input_event(input, EV_ABS, ABS_X, nd->x);
187 				input_event(input, EV_ABS, ABS_Y, nd->y);
188 				input_event(input, EV_ABS, ABS_PRESSURE, value);
189 			}
190 			break;
191 		case 0xff000002:
192 			/*
193 			 * we receive this when the device is in multitouch
194 			 * mode. The first of the three values tagged with
195 			 * this usage tells if the contact point is real
196 			 * or a placeholder
197 			 */
198 			if (!nd->reading_a_point || value != 1)
199 				break;
200 			/* emit a normal (X, Y) for the first point only */
201 			if (nd->id == 0) {
202 				input_event(input, EV_ABS, ABS_X, nd->x);
203 				input_event(input, EV_ABS, ABS_Y, nd->y);
204 			}
205 			input_event(input, EV_ABS, ABS_MT_POSITION_X, nd->x);
206 			input_event(input, EV_ABS, ABS_MT_POSITION_Y, nd->y);
207 			if (nd->w > nd->h) {
208 				input_event(input, EV_ABS,
209 						ABS_MT_ORIENTATION, 1);
210 				input_event(input, EV_ABS,
211 						ABS_MT_TOUCH_MAJOR, nd->w);
212 				input_event(input, EV_ABS,
213 						ABS_MT_TOUCH_MINOR, nd->h);
214 			} else {
215 				input_event(input, EV_ABS,
216 						ABS_MT_ORIENTATION, 0);
217 				input_event(input, EV_ABS,
218 						ABS_MT_TOUCH_MAJOR, nd->h);
219 				input_event(input, EV_ABS,
220 						ABS_MT_TOUCH_MINOR, nd->w);
221 			}
222 			input_mt_sync(field->hidinput->input);
223 			nd->reading_a_point = 0;
224 			nd->found_contact_id = 0;
225 			break;
226 
227 		default:
228 			/* fallback to the generic hidinput handling */
229 			return 0;
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 
240 static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
241 {
242 	int ret;
243 	struct ntrig_data *nd;
244 
245 	nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL);
246 	if (!nd) {
247 		dev_err(&hdev->dev, "cannot allocate N-Trig data\n");
248 		return -ENOMEM;
249 	}
250 	nd->reading_a_point = 0;
251 	nd->found_contact_id = 0;
252 	hid_set_drvdata(hdev, nd);
253 
254 	ret = hid_parse(hdev);
255 	if (!ret)
256 		ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
257 
258 	if (ret)
259 		kfree (nd);
260 
261 	return ret;
262 }
263 
264 static void ntrig_remove(struct hid_device *hdev)
265 {
266 	hid_hw_stop(hdev);
267 	kfree(hid_get_drvdata(hdev));
268 }
269 
270 static const struct hid_device_id ntrig_devices[] = {
271 	{ HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN),
272 		.driver_data = NTRIG_DUPLICATE_USAGES },
273 	{ }
274 };
275 MODULE_DEVICE_TABLE(hid, ntrig_devices);
276 
277 static const struct hid_usage_id ntrig_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 
282 static struct hid_driver ntrig_driver = {
283 	.name = "ntrig",
284 	.id_table = ntrig_devices,
285 	.probe = ntrig_probe,
286 	.remove = ntrig_remove,
287 	.input_mapping = ntrig_input_mapping,
288 	.input_mapped = ntrig_input_mapped,
289 	.usage_table = ntrig_grabbed_usages,
290 	.event = ntrig_event,
291 };
292 
293 static int __init ntrig_init(void)
294 {
295 	return hid_register_driver(&ntrig_driver);
296 }
297 
298 static void __exit ntrig_exit(void)
299 {
300 	hid_unregister_driver(&ntrig_driver);
301 }
302 
303 module_init(ntrig_init);
304 module_exit(ntrig_exit);
305 MODULE_LICENSE("GPL");
306