1 /*
2 * Penmount serial touchscreen driver
3 *
4 * Copyright (c) 2006 Rick Koch <n1gp@hotmail.com>
5 * Copyright (c) 2011 John Sung <penmount.touch@gmail.com>
6 *
7 * Based on ELO driver (drivers/input/touchscreen/elo.c)
8 * Copyright (c) 2004 Vojtech Pavlik
9 */
10
11 /*
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License version 2 as published
14 * by the Free Software Foundation.
15 */
16
17 #include <linux/errno.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/slab.h>
21 #include <linux/input.h>
22 #include <linux/input/mt.h>
23 #include <linux/serio.h>
24 #include <linux/init.h>
25
26 #define DRIVER_DESC "PenMount serial touchscreen driver"
27
28 MODULE_AUTHOR("Rick Koch <n1gp@hotmail.com>");
29 MODULE_AUTHOR("John Sung <penmount.touch@gmail.com>");
30 MODULE_DESCRIPTION(DRIVER_DESC);
31 MODULE_LICENSE("GPL");
32
33 /*
34 * Definitions & global arrays.
35 */
36
37 #define PM_MAX_LENGTH 6
38 #define PM_MAX_MTSLOT 16
39 #define PM_3000_MTSLOT 2
40 #define PM_6250_MTSLOT 12
41
42 /*
43 * Multi-touch slot
44 */
45
46 struct mt_slot {
47 unsigned short x, y;
48 bool active; /* is the touch valid? */
49 };
50
51 /*
52 * Per-touchscreen data.
53 */
54
55 struct pm {
56 struct input_dev *dev;
57 struct serio *serio;
58 int idx;
59 unsigned char data[PM_MAX_LENGTH];
60 char phys[32];
61 unsigned char packetsize;
62 unsigned char maxcontacts;
63 struct mt_slot slots[PM_MAX_MTSLOT];
64 void (*parse_packet)(struct pm *);
65 };
66
67 /*
68 * pm_mtevent() sends mt events and also emulates pointer movement
69 */
70
pm_mtevent(struct pm * pm,struct input_dev * input)71 static void pm_mtevent(struct pm *pm, struct input_dev *input)
72 {
73 int i;
74
75 for (i = 0; i < pm->maxcontacts; ++i) {
76 input_mt_slot(input, i);
77 input_mt_report_slot_state(input, MT_TOOL_FINGER,
78 pm->slots[i].active);
79 if (pm->slots[i].active) {
80 input_event(input, EV_ABS, ABS_MT_POSITION_X, pm->slots[i].x);
81 input_event(input, EV_ABS, ABS_MT_POSITION_Y, pm->slots[i].y);
82 }
83 }
84
85 input_mt_report_pointer_emulation(input, true);
86 input_sync(input);
87 }
88
89 /*
90 * pm_checkpacket() checks if data packet is valid
91 */
92
pm_checkpacket(unsigned char * packet)93 static bool pm_checkpacket(unsigned char *packet)
94 {
95 int total = 0;
96 int i;
97
98 for (i = 0; i < 5; i++)
99 total += packet[i];
100
101 return packet[5] == (unsigned char)~(total & 0xff);
102 }
103
pm_parse_9000(struct pm * pm)104 static void pm_parse_9000(struct pm *pm)
105 {
106 struct input_dev *dev = pm->dev;
107
108 if ((pm->data[0] & 0x80) && pm->packetsize == ++pm->idx) {
109 input_report_abs(dev, ABS_X, pm->data[1] * 128 + pm->data[2]);
110 input_report_abs(dev, ABS_Y, pm->data[3] * 128 + pm->data[4]);
111 input_report_key(dev, BTN_TOUCH, !!(pm->data[0] & 0x40));
112 input_sync(dev);
113 pm->idx = 0;
114 }
115 }
116
pm_parse_6000(struct pm * pm)117 static void pm_parse_6000(struct pm *pm)
118 {
119 struct input_dev *dev = pm->dev;
120
121 if ((pm->data[0] & 0xbf) == 0x30 && pm->packetsize == ++pm->idx) {
122 if (pm_checkpacket(pm->data)) {
123 input_report_abs(dev, ABS_X,
124 pm->data[2] * 256 + pm->data[1]);
125 input_report_abs(dev, ABS_Y,
126 pm->data[4] * 256 + pm->data[3]);
127 input_report_key(dev, BTN_TOUCH, pm->data[0] & 0x40);
128 input_sync(dev);
129 }
130 pm->idx = 0;
131 }
132 }
133
pm_parse_3000(struct pm * pm)134 static void pm_parse_3000(struct pm *pm)
135 {
136 struct input_dev *dev = pm->dev;
137
138 if ((pm->data[0] & 0xce) == 0x40 && pm->packetsize == ++pm->idx) {
139 if (pm_checkpacket(pm->data)) {
140 int slotnum = pm->data[0] & 0x0f;
141 pm->slots[slotnum].active = pm->data[0] & 0x30;
142 pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1];
143 pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3];
144 pm_mtevent(pm, dev);
145 }
146 pm->idx = 0;
147 }
148 }
149
pm_parse_6250(struct pm * pm)150 static void pm_parse_6250(struct pm *pm)
151 {
152 struct input_dev *dev = pm->dev;
153
154 if ((pm->data[0] & 0xb0) == 0x30 && pm->packetsize == ++pm->idx) {
155 if (pm_checkpacket(pm->data)) {
156 int slotnum = pm->data[0] & 0x0f;
157 pm->slots[slotnum].active = pm->data[0] & 0x40;
158 pm->slots[slotnum].x = pm->data[2] * 256 + pm->data[1];
159 pm->slots[slotnum].y = pm->data[4] * 256 + pm->data[3];
160 pm_mtevent(pm, dev);
161 }
162 pm->idx = 0;
163 }
164 }
165
pm_interrupt(struct serio * serio,unsigned char data,unsigned int flags)166 static irqreturn_t pm_interrupt(struct serio *serio,
167 unsigned char data, unsigned int flags)
168 {
169 struct pm *pm = serio_get_drvdata(serio);
170
171 pm->data[pm->idx] = data;
172
173 pm->parse_packet(pm);
174
175 return IRQ_HANDLED;
176 }
177
178 /*
179 * pm_disconnect() is the opposite of pm_connect()
180 */
181
pm_disconnect(struct serio * serio)182 static void pm_disconnect(struct serio *serio)
183 {
184 struct pm *pm = serio_get_drvdata(serio);
185
186 serio_close(serio);
187
188 input_unregister_device(pm->dev);
189 kfree(pm);
190
191 serio_set_drvdata(serio, NULL);
192 }
193
194 /*
195 * pm_connect() is the routine that is called when someone adds a
196 * new serio device that supports PenMount protocol and registers it as
197 * an input device.
198 */
199
pm_connect(struct serio * serio,struct serio_driver * drv)200 static int pm_connect(struct serio *serio, struct serio_driver *drv)
201 {
202 struct pm *pm;
203 struct input_dev *input_dev;
204 int max_x, max_y;
205 int err;
206
207 pm = kzalloc(sizeof(struct pm), GFP_KERNEL);
208 input_dev = input_allocate_device();
209 if (!pm || !input_dev) {
210 err = -ENOMEM;
211 goto fail1;
212 }
213
214 pm->serio = serio;
215 pm->dev = input_dev;
216 snprintf(pm->phys, sizeof(pm->phys), "%s/input0", serio->phys);
217 pm->maxcontacts = 1;
218
219 input_dev->name = "PenMount Serial TouchScreen";
220 input_dev->phys = pm->phys;
221 input_dev->id.bustype = BUS_RS232;
222 input_dev->id.vendor = SERIO_PENMOUNT;
223 input_dev->id.product = 0;
224 input_dev->id.version = 0x0100;
225 input_dev->dev.parent = &serio->dev;
226
227 input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
228 input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
229
230 switch (serio->id.id) {
231 default:
232 case 0:
233 pm->packetsize = 5;
234 pm->parse_packet = pm_parse_9000;
235 input_dev->id.product = 0x9000;
236 max_x = max_y = 0x3ff;
237 break;
238
239 case 1:
240 pm->packetsize = 6;
241 pm->parse_packet = pm_parse_6000;
242 input_dev->id.product = 0x6000;
243 max_x = max_y = 0x3ff;
244 break;
245
246 case 2:
247 pm->packetsize = 6;
248 pm->parse_packet = pm_parse_3000;
249 input_dev->id.product = 0x3000;
250 max_x = max_y = 0x7ff;
251 pm->maxcontacts = PM_3000_MTSLOT;
252 break;
253
254 case 3:
255 pm->packetsize = 6;
256 pm->parse_packet = pm_parse_6250;
257 input_dev->id.product = 0x6250;
258 max_x = max_y = 0x3ff;
259 pm->maxcontacts = PM_6250_MTSLOT;
260 break;
261 }
262
263 input_set_abs_params(pm->dev, ABS_X, 0, max_x, 0, 0);
264 input_set_abs_params(pm->dev, ABS_Y, 0, max_y, 0, 0);
265
266 if (pm->maxcontacts > 1) {
267 input_mt_init_slots(pm->dev, pm->maxcontacts);
268 input_set_abs_params(pm->dev,
269 ABS_MT_POSITION_X, 0, max_x, 0, 0);
270 input_set_abs_params(pm->dev,
271 ABS_MT_POSITION_Y, 0, max_y, 0, 0);
272 }
273
274 serio_set_drvdata(serio, pm);
275
276 err = serio_open(serio, drv);
277 if (err)
278 goto fail2;
279
280 err = input_register_device(pm->dev);
281 if (err)
282 goto fail3;
283
284 return 0;
285
286 fail3: serio_close(serio);
287 fail2: serio_set_drvdata(serio, NULL);
288 fail1: input_free_device(input_dev);
289 kfree(pm);
290 return err;
291 }
292
293 /*
294 * The serio driver structure.
295 */
296
297 static struct serio_device_id pm_serio_ids[] = {
298 {
299 .type = SERIO_RS232,
300 .proto = SERIO_PENMOUNT,
301 .id = SERIO_ANY,
302 .extra = SERIO_ANY,
303 },
304 { 0 }
305 };
306
307 MODULE_DEVICE_TABLE(serio, pm_serio_ids);
308
309 static struct serio_driver pm_drv = {
310 .driver = {
311 .name = "serio-penmount",
312 },
313 .description = DRIVER_DESC,
314 .id_table = pm_serio_ids,
315 .interrupt = pm_interrupt,
316 .connect = pm_connect,
317 .disconnect = pm_disconnect,
318 };
319
320 /*
321 * The functions for inserting/removing us as a module.
322 */
323
pm_init(void)324 static int __init pm_init(void)
325 {
326 return serio_register_driver(&pm_drv);
327 }
328
pm_exit(void)329 static void __exit pm_exit(void)
330 {
331 serio_unregister_driver(&pm_drv);
332 }
333
334 module_init(pm_init);
335 module_exit(pm_exit);
336