Input: wacom_w8001 - w8001_MAX_LENGTH should be 13
[pandora-kernel.git] / drivers / input / touchscreen / wacom_w8001.c
1 /*
2  * Wacom W8001 penabled serial touchscreen driver
3  *
4  * Copyright (c) 2008 Jaya Kumar
5  * Copyright (c) 2010 Red Hat, Inc.
6  * Copyright (c) 2010 - 2011 Ping Cheng, Wacom. <pingc@wacom.com>
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License. See the file COPYING in the main directory of this archive for
10  * more details.
11  *
12  * Layout based on Elo serial touchscreen driver by Vojtech Pavlik
13  */
14
15 #include <linux/errno.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/input/mt.h>
20 #include <linux/serio.h>
21 #include <linux/init.h>
22 #include <linux/ctype.h>
23 #include <linux/delay.h>
24
25 #define DRIVER_DESC     "Wacom W8001 serial touchscreen driver"
26
27 MODULE_AUTHOR("Jaya Kumar <jayakumar.lkml@gmail.com>");
28 MODULE_DESCRIPTION(DRIVER_DESC);
29 MODULE_LICENSE("GPL");
30
31 #define W8001_MAX_LENGTH        13
32 #define W8001_LEAD_MASK         0x80
33 #define W8001_LEAD_BYTE         0x80
34 #define W8001_TAB_MASK          0x40
35 #define W8001_TAB_BYTE          0x40
36 /* set in first byte of touch data packets */
37 #define W8001_TOUCH_MASK        (0x10 | W8001_LEAD_MASK)
38 #define W8001_TOUCH_BYTE        (0x10 | W8001_LEAD_BYTE)
39
40 #define W8001_QUERY_PACKET      0x20
41
42 #define W8001_CMD_STOP          '0'
43 #define W8001_CMD_START         '1'
44 #define W8001_CMD_QUERY         '*'
45 #define W8001_CMD_TOUCHQUERY    '%'
46
47 /* length of data packets in bytes, depends on device. */
48 #define W8001_PKTLEN_TOUCH93    5
49 #define W8001_PKTLEN_TOUCH9A    7
50 #define W8001_PKTLEN_TPCPEN     9
51 #define W8001_PKTLEN_TPCCTL     11      /* control packet */
52 #define W8001_PKTLEN_TOUCH2FG   13
53
54 /* resolution in points/mm */
55 #define W8001_PEN_RESOLUTION    100
56 #define W8001_TOUCH_RESOLUTION  10
57
58 struct w8001_coord {
59         u8 rdy;
60         u8 tsw;
61         u8 f1;
62         u8 f2;
63         u16 x;
64         u16 y;
65         u16 pen_pressure;
66         u8 tilt_x;
67         u8 tilt_y;
68 };
69
70 /* touch query reply packet */
71 struct w8001_touch_query {
72         u16 x;
73         u16 y;
74         u8 panel_res;
75         u8 capacity_res;
76         u8 sensor_id;
77 };
78
79 /*
80  * Per-touchscreen data.
81  */
82
83 struct w8001 {
84         struct input_dev *dev;
85         struct serio *serio;
86         struct completion cmd_done;
87         int id;
88         int idx;
89         unsigned char response_type;
90         unsigned char response[W8001_MAX_LENGTH];
91         unsigned char data[W8001_MAX_LENGTH];
92         char phys[32];
93         int type;
94         unsigned int pktlen;
95         u16 max_touch_x;
96         u16 max_touch_y;
97         u16 max_pen_x;
98         u16 max_pen_y;
99         char name[64];
100 };
101
102 static void parse_pen_data(u8 *data, struct w8001_coord *coord)
103 {
104         memset(coord, 0, sizeof(*coord));
105
106         coord->rdy = data[0] & 0x20;
107         coord->tsw = data[0] & 0x01;
108         coord->f1 = data[0] & 0x02;
109         coord->f2 = data[0] & 0x04;
110
111         coord->x = (data[1] & 0x7F) << 9;
112         coord->x |= (data[2] & 0x7F) << 2;
113         coord->x |= (data[6] & 0x60) >> 5;
114
115         coord->y = (data[3] & 0x7F) << 9;
116         coord->y |= (data[4] & 0x7F) << 2;
117         coord->y |= (data[6] & 0x18) >> 3;
118
119         coord->pen_pressure = data[5] & 0x7F;
120         coord->pen_pressure |= (data[6] & 0x07) << 7 ;
121
122         coord->tilt_x = data[7] & 0x7F;
123         coord->tilt_y = data[8] & 0x7F;
124 }
125
126 static void parse_single_touch(u8 *data, struct w8001_coord *coord)
127 {
128         coord->x = (data[1] << 7) | data[2];
129         coord->y = (data[3] << 7) | data[4];
130         coord->tsw = data[0] & 0x01;
131 }
132
133 static void scale_touch_coordinates(struct w8001 *w8001,
134                                     unsigned int *x, unsigned int *y)
135 {
136         if (w8001->max_pen_x && w8001->max_touch_x)
137                 *x = *x * w8001->max_pen_x / w8001->max_touch_x;
138
139         if (w8001->max_pen_y && w8001->max_touch_y)
140                 *y = *y * w8001->max_pen_y / w8001->max_touch_y;
141 }
142
143 static void parse_multi_touch(struct w8001 *w8001)
144 {
145         struct input_dev *dev = w8001->dev;
146         unsigned char *data = w8001->data;
147         unsigned int x, y;
148         int i;
149         int count = 0;
150
151         for (i = 0; i < 2; i++) {
152                 bool touch = data[0] & (1 << i);
153
154                 input_mt_slot(dev, i);
155                 input_mt_report_slot_state(dev, MT_TOOL_FINGER, touch);
156                 if (touch) {
157                         x = (data[6 * i + 1] << 7) | data[6 * i + 2];
158                         y = (data[6 * i + 3] << 7) | data[6 * i + 4];
159                         /* data[5,6] and [11,12] is finger capacity */
160
161                         /* scale to pen maximum */
162                         scale_touch_coordinates(w8001, &x, &y);
163
164                         input_report_abs(dev, ABS_MT_POSITION_X, x);
165                         input_report_abs(dev, ABS_MT_POSITION_Y, y);
166                         count++;
167                 }
168         }
169
170         /* emulate single touch events when stylus is out of proximity.
171          * This is to make single touch backward support consistent
172          * across all Wacom single touch devices.
173          */
174         if (w8001->type != BTN_TOOL_PEN &&
175                             w8001->type != BTN_TOOL_RUBBER) {
176                 w8001->type = count == 1 ? BTN_TOOL_FINGER : KEY_RESERVED;
177                 input_mt_report_pointer_emulation(dev, true);
178         }
179
180         input_sync(dev);
181 }
182
183 static void parse_touchquery(u8 *data, struct w8001_touch_query *query)
184 {
185         memset(query, 0, sizeof(*query));
186
187         query->panel_res = data[1];
188         query->sensor_id = data[2] & 0x7;
189         query->capacity_res = data[7];
190
191         query->x = data[3] << 9;
192         query->x |= data[4] << 2;
193         query->x |= (data[2] >> 5) & 0x3;
194
195         query->y = data[5] << 9;
196         query->y |= data[6] << 2;
197         query->y |= (data[2] >> 3) & 0x3;
198
199         /* Early days' single-finger touch models need the following defaults */
200         if (!query->x && !query->y) {
201                 query->x = 1024;
202                 query->y = 1024;
203                 if (query->panel_res)
204                         query->x = query->y = (1 << query->panel_res);
205                 query->panel_res = W8001_TOUCH_RESOLUTION;
206         }
207 }
208
209 static void report_pen_events(struct w8001 *w8001, struct w8001_coord *coord)
210 {
211         struct input_dev *dev = w8001->dev;
212
213         /*
214          * We have 1 bit for proximity (rdy) and 3 bits for tip, side,
215          * side2/eraser. If rdy && f2 are set, this can be either pen + side2,
216          * or eraser. Assume:
217          * - if dev is already in proximity and f2 is toggled → pen + side2
218          * - if dev comes into proximity with f2 set → eraser
219          * If f2 disappears after assuming eraser, fake proximity out for
220          * eraser and in for pen.
221          */
222
223         switch (w8001->type) {
224         case BTN_TOOL_RUBBER:
225                 if (!coord->f2) {
226                         input_report_abs(dev, ABS_PRESSURE, 0);
227                         input_report_key(dev, BTN_TOUCH, 0);
228                         input_report_key(dev, BTN_STYLUS, 0);
229                         input_report_key(dev, BTN_STYLUS2, 0);
230                         input_report_key(dev, BTN_TOOL_RUBBER, 0);
231                         input_sync(dev);
232                         w8001->type = BTN_TOOL_PEN;
233                 }
234                 break;
235
236         case BTN_TOOL_FINGER:
237                 input_report_key(dev, BTN_TOUCH, 0);
238                 input_report_key(dev, BTN_TOOL_FINGER, 0);
239                 input_sync(dev);
240                 /* fall through */
241
242         case KEY_RESERVED:
243                 w8001->type = coord->f2 ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
244                 break;
245
246         default:
247                 input_report_key(dev, BTN_STYLUS2, coord->f2);
248                 break;
249         }
250
251         input_report_abs(dev, ABS_X, coord->x);
252         input_report_abs(dev, ABS_Y, coord->y);
253         input_report_abs(dev, ABS_PRESSURE, coord->pen_pressure);
254         input_report_key(dev, BTN_TOUCH, coord->tsw);
255         input_report_key(dev, BTN_STYLUS, coord->f1);
256         input_report_key(dev, w8001->type, coord->rdy);
257         input_sync(dev);
258
259         if (!coord->rdy)
260                 w8001->type = KEY_RESERVED;
261 }
262
263 static void report_single_touch(struct w8001 *w8001, struct w8001_coord *coord)
264 {
265         struct input_dev *dev = w8001->dev;
266         unsigned int x = coord->x;
267         unsigned int y = coord->y;
268
269         /* scale to pen maximum */
270         scale_touch_coordinates(w8001, &x, &y);
271
272         input_report_abs(dev, ABS_X, x);
273         input_report_abs(dev, ABS_Y, y);
274         input_report_key(dev, BTN_TOUCH, coord->tsw);
275         input_report_key(dev, BTN_TOOL_FINGER, coord->tsw);
276
277         input_sync(dev);
278
279         w8001->type = coord->tsw ? BTN_TOOL_FINGER : KEY_RESERVED;
280 }
281
282 static irqreturn_t w8001_interrupt(struct serio *serio,
283                                    unsigned char data, unsigned int flags)
284 {
285         struct w8001 *w8001 = serio_get_drvdata(serio);
286         struct w8001_coord coord;
287         unsigned char tmp;
288
289         w8001->data[w8001->idx] = data;
290         switch (w8001->idx++) {
291         case 0:
292                 if ((data & W8001_LEAD_MASK) != W8001_LEAD_BYTE) {
293                         pr_debug("w8001: unsynchronized data: 0x%02x\n", data);
294                         w8001->idx = 0;
295                 }
296                 break;
297
298         case W8001_PKTLEN_TOUCH93 - 1:
299         case W8001_PKTLEN_TOUCH9A - 1:
300                 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
301                 if (tmp != W8001_TOUCH_BYTE)
302                         break;
303
304                 if (w8001->pktlen == w8001->idx) {
305                         w8001->idx = 0;
306                         if (w8001->type != BTN_TOOL_PEN &&
307                             w8001->type != BTN_TOOL_RUBBER) {
308                                 parse_single_touch(w8001->data, &coord);
309                                 report_single_touch(w8001, &coord);
310                         }
311                 }
312                 break;
313
314         /* Pen coordinates packet */
315         case W8001_PKTLEN_TPCPEN - 1:
316                 tmp = w8001->data[0] & W8001_TAB_MASK;
317                 if (unlikely(tmp == W8001_TAB_BYTE))
318                         break;
319
320                 tmp = w8001->data[0] & W8001_TOUCH_BYTE;
321                 if (tmp == W8001_TOUCH_BYTE)
322                         break;
323
324                 w8001->idx = 0;
325                 parse_pen_data(w8001->data, &coord);
326                 report_pen_events(w8001, &coord);
327                 break;
328
329         /* control packet */
330         case W8001_PKTLEN_TPCCTL - 1:
331                 tmp = w8001->data[0] & W8001_TOUCH_MASK;
332                 if (tmp == W8001_TOUCH_BYTE)
333                         break;
334
335                 w8001->idx = 0;
336                 memcpy(w8001->response, w8001->data, W8001_MAX_LENGTH);
337                 w8001->response_type = W8001_QUERY_PACKET;
338                 complete(&w8001->cmd_done);
339                 break;
340
341         /* 2 finger touch packet */
342         case W8001_PKTLEN_TOUCH2FG - 1:
343                 w8001->idx = 0;
344                 parse_multi_touch(w8001);
345                 break;
346         }
347
348         return IRQ_HANDLED;
349 }
350
351 static int w8001_command(struct w8001 *w8001, unsigned char command,
352                          bool wait_response)
353 {
354         int rc;
355
356         w8001->response_type = 0;
357         init_completion(&w8001->cmd_done);
358
359         rc = serio_write(w8001->serio, command);
360         if (rc == 0 && wait_response) {
361
362                 wait_for_completion_timeout(&w8001->cmd_done, HZ);
363                 if (w8001->response_type != W8001_QUERY_PACKET)
364                         rc = -EIO;
365         }
366
367         return rc;
368 }
369
370 static int w8001_open(struct input_dev *dev)
371 {
372         struct w8001 *w8001 = input_get_drvdata(dev);
373
374         return w8001_command(w8001, W8001_CMD_START, false);
375 }
376
377 static void w8001_close(struct input_dev *dev)
378 {
379         struct w8001 *w8001 = input_get_drvdata(dev);
380
381         w8001_command(w8001, W8001_CMD_STOP, false);
382 }
383
384 static int w8001_setup(struct w8001 *w8001)
385 {
386         struct input_dev *dev = w8001->dev;
387         struct w8001_coord coord;
388         struct w8001_touch_query touch;
389         int error;
390
391         error = w8001_command(w8001, W8001_CMD_STOP, false);
392         if (error)
393                 return error;
394
395         msleep(250);    /* wait 250ms before querying the device */
396
397         dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
398         strlcat(w8001->name, "Wacom Serial", sizeof(w8001->name));
399
400         __set_bit(INPUT_PROP_DIRECT, dev->propbit);
401
402         /* penabled? */
403         error = w8001_command(w8001, W8001_CMD_QUERY, true);
404         if (!error) {
405                 __set_bit(BTN_TOUCH, dev->keybit);
406                 __set_bit(BTN_TOOL_PEN, dev->keybit);
407                 __set_bit(BTN_TOOL_RUBBER, dev->keybit);
408                 __set_bit(BTN_STYLUS, dev->keybit);
409                 __set_bit(BTN_STYLUS2, dev->keybit);
410
411                 parse_pen_data(w8001->response, &coord);
412                 w8001->max_pen_x = coord.x;
413                 w8001->max_pen_y = coord.y;
414
415                 input_set_abs_params(dev, ABS_X, 0, coord.x, 0, 0);
416                 input_set_abs_params(dev, ABS_Y, 0, coord.y, 0, 0);
417                 input_abs_set_res(dev, ABS_X, W8001_PEN_RESOLUTION);
418                 input_abs_set_res(dev, ABS_Y, W8001_PEN_RESOLUTION);
419                 input_set_abs_params(dev, ABS_PRESSURE, 0, coord.pen_pressure, 0, 0);
420                 if (coord.tilt_x && coord.tilt_y) {
421                         input_set_abs_params(dev, ABS_TILT_X, 0, coord.tilt_x, 0, 0);
422                         input_set_abs_params(dev, ABS_TILT_Y, 0, coord.tilt_y, 0, 0);
423                 }
424                 w8001->id = 0x90;
425                 strlcat(w8001->name, " Penabled", sizeof(w8001->name));
426         }
427
428         /* Touch enabled? */
429         error = w8001_command(w8001, W8001_CMD_TOUCHQUERY, true);
430
431         /*
432          * Some non-touch devices may reply to the touch query. But their
433          * second byte is empty, which indicates touch is not supported.
434          */
435         if (!error && w8001->response[1]) {
436                 __set_bit(BTN_TOUCH, dev->keybit);
437                 __set_bit(BTN_TOOL_FINGER, dev->keybit);
438
439                 parse_touchquery(w8001->response, &touch);
440                 w8001->max_touch_x = touch.x;
441                 w8001->max_touch_y = touch.y;
442
443                 if (w8001->max_pen_x && w8001->max_pen_y) {
444                         /* if pen is supported scale to pen maximum */
445                         touch.x = w8001->max_pen_x;
446                         touch.y = w8001->max_pen_y;
447                         touch.panel_res = W8001_PEN_RESOLUTION;
448                 }
449
450                 input_set_abs_params(dev, ABS_X, 0, touch.x, 0, 0);
451                 input_set_abs_params(dev, ABS_Y, 0, touch.y, 0, 0);
452                 input_abs_set_res(dev, ABS_X, touch.panel_res);
453                 input_abs_set_res(dev, ABS_Y, touch.panel_res);
454
455                 switch (touch.sensor_id) {
456                 case 0:
457                 case 2:
458                         w8001->pktlen = W8001_PKTLEN_TOUCH93;
459                         w8001->id = 0x93;
460                         strlcat(w8001->name, " 1FG", sizeof(w8001->name));
461                         break;
462
463                 case 1:
464                 case 3:
465                 case 4:
466                         w8001->pktlen = W8001_PKTLEN_TOUCH9A;
467                         strlcat(w8001->name, " 1FG", sizeof(w8001->name));
468                         w8001->id = 0x9a;
469                         break;
470
471                 case 5:
472                         w8001->pktlen = W8001_PKTLEN_TOUCH2FG;
473
474                         input_mt_init_slots(dev, 2);
475                         input_set_abs_params(dev, ABS_MT_POSITION_X,
476                                                 0, touch.x, 0, 0);
477                         input_set_abs_params(dev, ABS_MT_POSITION_Y,
478                                                 0, touch.y, 0, 0);
479                         input_set_abs_params(dev, ABS_MT_TOOL_TYPE,
480                                                 0, MT_TOOL_MAX, 0, 0);
481
482                         strlcat(w8001->name, " 2FG", sizeof(w8001->name));
483                         if (w8001->max_pen_x && w8001->max_pen_y)
484                                 w8001->id = 0xE3;
485                         else
486                                 w8001->id = 0xE2;
487                         break;
488                 }
489         }
490
491         strlcat(w8001->name, " Touchscreen", sizeof(w8001->name));
492
493         return 0;
494 }
495
496 /*
497  * w8001_disconnect() is the opposite of w8001_connect()
498  */
499
500 static void w8001_disconnect(struct serio *serio)
501 {
502         struct w8001 *w8001 = serio_get_drvdata(serio);
503
504         serio_close(serio);
505
506         input_unregister_device(w8001->dev);
507         kfree(w8001);
508
509         serio_set_drvdata(serio, NULL);
510 }
511
512 /*
513  * w8001_connect() is the routine that is called when someone adds a
514  * new serio device that supports the w8001 protocol and registers it as
515  * an input device.
516  */
517
518 static int w8001_connect(struct serio *serio, struct serio_driver *drv)
519 {
520         struct w8001 *w8001;
521         struct input_dev *input_dev;
522         int err;
523
524         w8001 = kzalloc(sizeof(struct w8001), GFP_KERNEL);
525         input_dev = input_allocate_device();
526         if (!w8001 || !input_dev) {
527                 err = -ENOMEM;
528                 goto fail1;
529         }
530
531         w8001->serio = serio;
532         w8001->dev = input_dev;
533         init_completion(&w8001->cmd_done);
534         snprintf(w8001->phys, sizeof(w8001->phys), "%s/input0", serio->phys);
535
536         serio_set_drvdata(serio, w8001);
537         err = serio_open(serio, drv);
538         if (err)
539                 goto fail2;
540
541         err = w8001_setup(w8001);
542         if (err)
543                 goto fail3;
544
545         input_dev->name = w8001->name;
546         input_dev->phys = w8001->phys;
547         input_dev->id.product = w8001->id;
548         input_dev->id.bustype = BUS_RS232;
549         input_dev->id.vendor = 0x056a;
550         input_dev->id.version = 0x0100;
551         input_dev->dev.parent = &serio->dev;
552
553         input_dev->open = w8001_open;
554         input_dev->close = w8001_close;
555
556         input_set_drvdata(input_dev, w8001);
557
558         err = input_register_device(w8001->dev);
559         if (err)
560                 goto fail3;
561
562         return 0;
563
564 fail3:
565         serio_close(serio);
566 fail2:
567         serio_set_drvdata(serio, NULL);
568 fail1:
569         input_free_device(input_dev);
570         kfree(w8001);
571         return err;
572 }
573
574 static struct serio_device_id w8001_serio_ids[] = {
575         {
576                 .type   = SERIO_RS232,
577                 .proto  = SERIO_W8001,
578                 .id     = SERIO_ANY,
579                 .extra  = SERIO_ANY,
580         },
581         { 0 }
582 };
583
584 MODULE_DEVICE_TABLE(serio, w8001_serio_ids);
585
586 static struct serio_driver w8001_drv = {
587         .driver         = {
588                 .name   = "w8001",
589         },
590         .description    = DRIVER_DESC,
591         .id_table       = w8001_serio_ids,
592         .interrupt      = w8001_interrupt,
593         .connect        = w8001_connect,
594         .disconnect     = w8001_disconnect,
595 };
596
597 static int __init w8001_init(void)
598 {
599         return serio_register_driver(&w8001_drv);
600 }
601
602 static void __exit w8001_exit(void)
603 {
604         serio_unregister_driver(&w8001_drv);
605 }
606
607 module_init(w8001_init);
608 module_exit(w8001_exit);