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