Input: reduce raciness when input handlers disconnect
[linux-2.6.git] / drivers / input / mousedev.c
1 /*
2  * Input driver to ExplorerPS/2 device driver module.
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  * Copyright (c) 2004      Dmitry Torokhov
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as published by
9  * the Free Software Foundation.
10  */
11
12 #define MOUSEDEV_MINOR_BASE     32
13 #define MOUSEDEV_MINORS         32
14 #define MOUSEDEV_MIX            31
15
16 #include <linux/slab.h>
17 #include <linux/poll.h>
18 #include <linux/module.h>
19 #include <linux/moduleparam.h>
20 #include <linux/init.h>
21 #include <linux/input.h>
22 #include <linux/smp_lock.h>
23 #include <linux/random.h>
24 #include <linux/major.h>
25 #include <linux/device.h>
26 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
27 #include <linux/miscdevice.h>
28 #endif
29
30 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
31 MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces");
32 MODULE_LICENSE("GPL");
33
34 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X
35 #define CONFIG_INPUT_MOUSEDEV_SCREEN_X  1024
36 #endif
37 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y
38 #define CONFIG_INPUT_MOUSEDEV_SCREEN_Y  768
39 #endif
40
41 static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
42 module_param(xres, uint, 0644);
43 MODULE_PARM_DESC(xres, "Horizontal screen resolution");
44
45 static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
46 module_param(yres, uint, 0644);
47 MODULE_PARM_DESC(yres, "Vertical screen resolution");
48
49 static unsigned tap_time = 200;
50 module_param(tap_time, uint, 0644);
51 MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)");
52
53 struct mousedev_hw_data {
54         int dx, dy, dz;
55         int x, y;
56         int abs_event;
57         unsigned long buttons;
58 };
59
60 struct mousedev {
61         int exist;
62         int open;
63         int minor;
64         char name[16];
65         wait_queue_head_t wait;
66         struct list_head client_list;
67         struct input_handle handle;
68
69         struct list_head mixdev_node;
70         int mixdev_open;
71
72         struct mousedev_hw_data packet;
73         unsigned int pkt_count;
74         int old_x[4], old_y[4];
75         int frac_dx, frac_dy;
76         unsigned long touch;
77 };
78
79 enum mousedev_emul {
80         MOUSEDEV_EMUL_PS2,
81         MOUSEDEV_EMUL_IMPS,
82         MOUSEDEV_EMUL_EXPS
83 };
84
85 struct mousedev_motion {
86         int dx, dy, dz;
87         unsigned long buttons;
88 };
89
90 #define PACKET_QUEUE_LEN        16
91 struct mousedev_client {
92         struct fasync_struct *fasync;
93         struct mousedev *mousedev;
94         struct list_head node;
95
96         struct mousedev_motion packets[PACKET_QUEUE_LEN];
97         unsigned int head, tail;
98         spinlock_t packet_lock;
99         int pos_x, pos_y;
100
101         signed char ps2[6];
102         unsigned char ready, buffer, bufsiz;
103         unsigned char imexseq, impsseq;
104         enum mousedev_emul mode;
105         unsigned long last_buttons;
106 };
107
108 #define MOUSEDEV_SEQ_LEN        6
109
110 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
111 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
112
113 static struct input_handler mousedev_handler;
114
115 static struct mousedev *mousedev_table[MOUSEDEV_MINORS];
116 static struct mousedev mousedev_mix;
117 static LIST_HEAD(mousedev_mix_list);
118
119 #define fx(i)  (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
120 #define fy(i)  (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
121
122 static void mousedev_touchpad_event(struct input_dev *dev, struct mousedev *mousedev, unsigned int code, int value)
123 {
124         int size, tmp;
125         enum { FRACTION_DENOM = 128 };
126
127         switch (code) {
128                 case ABS_X:
129                         fx(0) = value;
130                         if (mousedev->touch && mousedev->pkt_count >= 2) {
131                                 size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
132                                 if (size == 0)
133                                         size = 256 * 2;
134                                 tmp = ((value - fx(2)) * (256 * FRACTION_DENOM)) / size;
135                                 tmp += mousedev->frac_dx;
136                                 mousedev->packet.dx = tmp / FRACTION_DENOM;
137                                 mousedev->frac_dx = tmp - mousedev->packet.dx * FRACTION_DENOM;
138                         }
139                         break;
140
141                 case ABS_Y:
142                         fy(0) = value;
143                         if (mousedev->touch && mousedev->pkt_count >= 2) {
144                                 /* use X size to keep the same scale */
145                                 size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
146                                 if (size == 0)
147                                         size = 256 * 2;
148                                 tmp = -((value - fy(2)) * (256 * FRACTION_DENOM)) / size;
149                                 tmp += mousedev->frac_dy;
150                                 mousedev->packet.dy = tmp / FRACTION_DENOM;
151                                 mousedev->frac_dy = tmp - mousedev->packet.dy * FRACTION_DENOM;
152                         }
153                         break;
154         }
155 }
156
157 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev, unsigned int code, int value)
158 {
159         int size;
160
161         switch (code) {
162                 case ABS_X:
163                         size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
164                         if (size == 0)
165                                 size = xres ? : 1;
166                         if (value > dev->absmax[ABS_X])
167                                 value = dev->absmax[ABS_X];
168                         if (value < dev->absmin[ABS_X])
169                                 value = dev->absmin[ABS_X];
170                         mousedev->packet.x = ((value - dev->absmin[ABS_X]) * xres) / size;
171                         mousedev->packet.abs_event = 1;
172                         break;
173
174                 case ABS_Y:
175                         size = dev->absmax[ABS_Y] - dev->absmin[ABS_Y];
176                         if (size == 0)
177                                 size = yres ? : 1;
178                         if (value > dev->absmax[ABS_Y])
179                                 value = dev->absmax[ABS_Y];
180                         if (value < dev->absmin[ABS_Y])
181                                 value = dev->absmin[ABS_Y];
182                         mousedev->packet.y = yres - ((value - dev->absmin[ABS_Y]) * yres) / size;
183                         mousedev->packet.abs_event = 1;
184                         break;
185         }
186 }
187
188 static void mousedev_rel_event(struct mousedev *mousedev, unsigned int code, int value)
189 {
190         switch (code) {
191                 case REL_X:     mousedev->packet.dx += value; break;
192                 case REL_Y:     mousedev->packet.dy -= value; break;
193                 case REL_WHEEL: mousedev->packet.dz -= value; break;
194         }
195 }
196
197 static void mousedev_key_event(struct mousedev *mousedev, unsigned int code, int value)
198 {
199         int index;
200
201         switch (code) {
202                 case BTN_TOUCH:
203                 case BTN_0:
204                 case BTN_LEFT:          index = 0; break;
205                 case BTN_STYLUS:
206                 case BTN_1:
207                 case BTN_RIGHT:         index = 1; break;
208                 case BTN_2:
209                 case BTN_FORWARD:
210                 case BTN_STYLUS2:
211                 case BTN_MIDDLE:        index = 2; break;
212                 case BTN_3:
213                 case BTN_BACK:
214                 case BTN_SIDE:          index = 3; break;
215                 case BTN_4:
216                 case BTN_EXTRA:         index = 4; break;
217                 default:                return;
218         }
219
220         if (value) {
221                 set_bit(index, &mousedev->packet.buttons);
222                 set_bit(index, &mousedev_mix.packet.buttons);
223         } else {
224                 clear_bit(index, &mousedev->packet.buttons);
225                 clear_bit(index, &mousedev_mix.packet.buttons);
226         }
227 }
228
229 static void mousedev_notify_readers(struct mousedev *mousedev, struct mousedev_hw_data *packet)
230 {
231         struct mousedev_client *client;
232         struct mousedev_motion *p;
233         unsigned long flags;
234         int wake_readers = 0;
235
236         list_for_each_entry(client, &mousedev->client_list, node) {
237                 spin_lock_irqsave(&client->packet_lock, flags);
238
239                 p = &client->packets[client->head];
240                 if (client->ready && p->buttons != mousedev->packet.buttons) {
241                         unsigned int new_head = (client->head + 1) % PACKET_QUEUE_LEN;
242                         if (new_head != client->tail) {
243                                 p = &client->packets[client->head = new_head];
244                                 memset(p, 0, sizeof(struct mousedev_motion));
245                         }
246                 }
247
248                 if (packet->abs_event) {
249                         p->dx += packet->x - client->pos_x;
250                         p->dy += packet->y - client->pos_y;
251                         client->pos_x = packet->x;
252                         client->pos_y = packet->y;
253                 }
254
255                 client->pos_x += packet->dx;
256                 client->pos_x = client->pos_x < 0 ? 0 : (client->pos_x >= xres ? xres : client->pos_x);
257                 client->pos_y += packet->dy;
258                 client->pos_y = client->pos_y < 0 ? 0 : (client->pos_y >= yres ? yres : client->pos_y);
259
260                 p->dx += packet->dx;
261                 p->dy += packet->dy;
262                 p->dz += packet->dz;
263                 p->buttons = mousedev->packet.buttons;
264
265                 if (p->dx || p->dy || p->dz || p->buttons != client->last_buttons)
266                         client->ready = 1;
267
268                 spin_unlock_irqrestore(&client->packet_lock, flags);
269
270                 if (client->ready) {
271                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
272                         wake_readers = 1;
273                 }
274         }
275
276         if (wake_readers)
277                 wake_up_interruptible(&mousedev->wait);
278 }
279
280 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
281 {
282         if (!value) {
283                 if (mousedev->touch &&
284                     time_before(jiffies, mousedev->touch + msecs_to_jiffies(tap_time))) {
285                         /*
286                          * Toggle left button to emulate tap.
287                          * We rely on the fact that mousedev_mix always has 0
288                          * motion packet so we won't mess current position.
289                          */
290                         set_bit(0, &mousedev->packet.buttons);
291                         set_bit(0, &mousedev_mix.packet.buttons);
292                         mousedev_notify_readers(mousedev, &mousedev_mix.packet);
293                         mousedev_notify_readers(&mousedev_mix, &mousedev_mix.packet);
294                         clear_bit(0, &mousedev->packet.buttons);
295                         clear_bit(0, &mousedev_mix.packet.buttons);
296                 }
297                 mousedev->touch = mousedev->pkt_count = 0;
298                 mousedev->frac_dx = 0;
299                 mousedev->frac_dy = 0;
300
301         } else if (!mousedev->touch)
302                 mousedev->touch = jiffies;
303 }
304
305 static void mousedev_event(struct input_handle *handle, unsigned int type, unsigned int code, int value)
306 {
307         struct mousedev *mousedev = handle->private;
308
309         switch (type) {
310                 case EV_ABS:
311                         /* Ignore joysticks */
312                         if (test_bit(BTN_TRIGGER, handle->dev->keybit))
313                                 return;
314
315                         if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
316                                 mousedev_touchpad_event(handle->dev, mousedev, code, value);
317                         else
318                                 mousedev_abs_event(handle->dev, mousedev, code, value);
319
320                         break;
321
322                 case EV_REL:
323                         mousedev_rel_event(mousedev, code, value);
324                         break;
325
326                 case EV_KEY:
327                         if (value != 2) {
328                                 if (code == BTN_TOUCH && test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
329                                         mousedev_touchpad_touch(mousedev, value);
330                                 else
331                                         mousedev_key_event(mousedev, code, value);
332                         }
333                         break;
334
335                 case EV_SYN:
336                         if (code == SYN_REPORT) {
337                                 if (mousedev->touch) {
338                                         mousedev->pkt_count++;
339                                         /* Input system eats duplicate events, but we need all of them
340                                          * to do correct averaging so apply present one forward
341                                          */
342                                         fx(0) = fx(1);
343                                         fy(0) = fy(1);
344                                 }
345
346                                 mousedev_notify_readers(mousedev, &mousedev->packet);
347                                 mousedev_notify_readers(&mousedev_mix, &mousedev->packet);
348
349                                 mousedev->packet.dx = mousedev->packet.dy = mousedev->packet.dz = 0;
350                                 mousedev->packet.abs_event = 0;
351                         }
352                         break;
353         }
354 }
355
356 static int mousedev_fasync(int fd, struct file *file, int on)
357 {
358         int retval;
359         struct mousedev_client *client = file->private_data;
360
361         retval = fasync_helper(fd, file, on, &client->fasync);
362
363         return retval < 0 ? retval : 0;
364 }
365
366 static void mousedev_free(struct mousedev *mousedev)
367 {
368         mousedev_table[mousedev->minor] = NULL;
369         kfree(mousedev);
370 }
371
372 static int mixdev_add_device(struct mousedev *mousedev)
373 {
374         int error;
375
376         if (mousedev_mix.open) {
377                 error = input_open_device(&mousedev->handle);
378                 if (error)
379                         return error;
380
381                 mousedev->open++;
382                 mousedev->mixdev_open++;
383         }
384
385         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
386
387         return 0;
388 }
389
390 static void mixdev_remove_device(struct mousedev *mousedev)
391 {
392         if (mousedev->mixdev_open) {
393                 mousedev->mixdev_open = 0;
394                 if (!--mousedev->open && mousedev->exist)
395                         input_close_device(&mousedev->handle);
396         }
397
398         list_del_init(&mousedev->mixdev_node);
399 }
400
401 static void mixdev_open_devices(void)
402 {
403         struct mousedev *mousedev;
404
405         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
406                 if (mousedev->exist && !mousedev->open) {
407                         if (input_open_device(&mousedev->handle))
408                                 continue;
409
410                         mousedev->open++;
411                         mousedev->mixdev_open++;
412                 }
413         }
414 }
415
416 static void mixdev_close_devices(void)
417 {
418         struct mousedev *mousedev, *next;
419
420         list_for_each_entry_safe(mousedev, next, &mousedev_mix_list, mixdev_node) {
421                 if (mousedev->mixdev_open) {
422                         mousedev->mixdev_open = 0;
423                         if (!--mousedev->open) {
424                                 if (mousedev->exist)
425                                         input_close_device(&mousedev->handle);
426                                 else
427                                         mousedev_free(mousedev);
428                         }
429                 }
430         }
431 }
432
433 static int mousedev_release(struct inode *inode, struct file *file)
434 {
435         struct mousedev_client *client = file->private_data;
436         struct mousedev *mousedev = client->mousedev;
437
438         mousedev_fasync(-1, file, 0);
439
440         list_del(&client->node);
441         kfree(client);
442
443         if (!--mousedev->open) {
444                 if (mousedev->minor == MOUSEDEV_MIX)
445                         mixdev_close_devices();
446                 else if (mousedev->exist)
447                         input_close_device(&mousedev->handle);
448                 else
449                         mousedev_free(mousedev);
450         }
451
452         return 0;
453 }
454
455
456 static int mousedev_open(struct inode *inode, struct file *file)
457 {
458         struct mousedev_client *client;
459         struct mousedev *mousedev;
460         int error;
461         int i;
462
463 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
464         if (imajor(inode) == MISC_MAJOR)
465                 i = MOUSEDEV_MIX;
466         else
467 #endif
468                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
469
470         if (i >= MOUSEDEV_MINORS)
471                 return -ENODEV;
472
473         mousedev = mousedev_table[i];
474         if (!mousedev)
475                 return -ENODEV;
476
477         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
478         if (!client)
479                 return -ENOMEM;
480
481         spin_lock_init(&client->packet_lock);
482         client->pos_x = xres / 2;
483         client->pos_y = yres / 2;
484         client->mousedev = mousedev;
485         list_add_tail(&client->node, &mousedev->client_list);
486
487         if (!mousedev->open++) {
488                 if (mousedev->minor == MOUSEDEV_MIX)
489                         mixdev_open_devices();
490                 else if (mousedev->exist) {
491                         error = input_open_device(&mousedev->handle);
492                         if (error) {
493                                 list_del(&client->node);
494                                 kfree(client);
495                                 return error;
496                         }
497                 }
498         }
499
500         file->private_data = client;
501         return 0;
502 }
503
504 static inline int mousedev_limit_delta(int delta, int limit)
505 {
506         return delta > limit ? limit : (delta < -limit ? -limit : delta);
507 }
508
509 static void mousedev_packet(struct mousedev_client *client, signed char *ps2_data)
510 {
511         struct mousedev_motion *p;
512         unsigned long flags;
513
514         spin_lock_irqsave(&client->packet_lock, flags);
515         p = &client->packets[client->tail];
516
517         ps2_data[0] = 0x08 | ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
518         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
519         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
520         p->dx -= ps2_data[1];
521         p->dy -= ps2_data[2];
522
523         switch (client->mode) {
524                 case MOUSEDEV_EMUL_EXPS:
525                         ps2_data[3] = mousedev_limit_delta(p->dz, 7);
526                         p->dz -= ps2_data[3];
527                         ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
528                         client->bufsiz = 4;
529                         break;
530
531                 case MOUSEDEV_EMUL_IMPS:
532                         ps2_data[0] |= ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
533                         ps2_data[3] = mousedev_limit_delta(p->dz, 127);
534                         p->dz -= ps2_data[3];
535                         client->bufsiz = 4;
536                         break;
537
538                 case MOUSEDEV_EMUL_PS2:
539                 default:
540                         ps2_data[0] |= ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
541                         p->dz = 0;
542                         client->bufsiz = 3;
543                         break;
544         }
545
546         if (!p->dx && !p->dy && !p->dz) {
547                 if (client->tail == client->head) {
548                         client->ready = 0;
549                         client->last_buttons = p->buttons;
550                 } else
551                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
552         }
553
554         spin_unlock_irqrestore(&client->packet_lock, flags);
555 }
556
557
558 static ssize_t mousedev_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
559 {
560         struct mousedev_client *client = file->private_data;
561         unsigned char c;
562         unsigned int i;
563
564         for (i = 0; i < count; i++) {
565
566                 if (get_user(c, buffer + i))
567                         return -EFAULT;
568
569                 if (c == mousedev_imex_seq[client->imexseq]) {
570                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
571                                 client->imexseq = 0;
572                                 client->mode = MOUSEDEV_EMUL_EXPS;
573                         }
574                 } else
575                         client->imexseq = 0;
576
577                 if (c == mousedev_imps_seq[client->impsseq]) {
578                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
579                                 client->impsseq = 0;
580                                 client->mode = MOUSEDEV_EMUL_IMPS;
581                         }
582                 } else
583                         client->impsseq = 0;
584
585                 client->ps2[0] = 0xfa;
586
587                 switch (c) {
588
589                         case 0xeb: /* Poll */
590                                 mousedev_packet(client, &client->ps2[1]);
591                                 client->bufsiz++; /* account for leading ACK */
592                                 break;
593
594                         case 0xf2: /* Get ID */
595                                 switch (client->mode) {
596                                         case MOUSEDEV_EMUL_PS2:  client->ps2[1] = 0; break;
597                                         case MOUSEDEV_EMUL_IMPS: client->ps2[1] = 3; break;
598                                         case MOUSEDEV_EMUL_EXPS: client->ps2[1] = 4; break;
599                                 }
600                                 client->bufsiz = 2;
601                                 break;
602
603                         case 0xe9: /* Get info */
604                                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
605                                 client->bufsiz = 4;
606                                 break;
607
608                         case 0xff: /* Reset */
609                                 client->impsseq = client->imexseq = 0;
610                                 client->mode = MOUSEDEV_EMUL_PS2;
611                                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
612                                 client->bufsiz = 3;
613                                 break;
614
615                         default:
616                                 client->bufsiz = 1;
617                                 break;
618                 }
619
620                 client->buffer = client->bufsiz;
621         }
622
623         kill_fasync(&client->fasync, SIGIO, POLL_IN);
624
625         wake_up_interruptible(&client->mousedev->wait);
626
627         return count;
628 }
629
630 static ssize_t mousedev_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
631 {
632         struct mousedev_client *client = file->private_data;
633         int retval = 0;
634
635         if (!client->ready && !client->buffer && (file->f_flags & O_NONBLOCK))
636                 return -EAGAIN;
637
638         retval = wait_event_interruptible(client->mousedev->wait,
639                                           !client->mousedev->exist || client->ready || client->buffer);
640
641         if (retval)
642                 return retval;
643
644         if (!client->mousedev->exist)
645                 return -ENODEV;
646
647         if (!client->buffer && client->ready) {
648                 mousedev_packet(client, client->ps2);
649                 client->buffer = client->bufsiz;
650         }
651
652         if (count > client->buffer)
653                 count = client->buffer;
654
655         client->buffer -= count;
656
657         if (copy_to_user(buffer, client->ps2 + client->bufsiz - client->buffer - count, count))
658                 return -EFAULT;
659
660         return count;
661 }
662
663 /* No kernel lock - fine */
664 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
665 {
666         struct mousedev_client *client = file->private_data;
667         struct mousedev *mousedev = client->mousedev;
668
669         poll_wait(file, &mousedev->wait, wait);
670         return ((client->ready || client->buffer) ? (POLLIN | POLLRDNORM) : 0) |
671                 (mousedev->exist ? 0 : (POLLHUP | POLLERR));
672 }
673
674 static const struct file_operations mousedev_fops = {
675         .owner =        THIS_MODULE,
676         .read =         mousedev_read,
677         .write =        mousedev_write,
678         .poll =         mousedev_poll,
679         .open =         mousedev_open,
680         .release =      mousedev_release,
681         .fasync =       mousedev_fasync,
682 };
683
684 static int mousedev_connect(struct input_handler *handler, struct input_dev *dev,
685                             const struct input_device_id *id)
686 {
687         struct mousedev *mousedev;
688         struct class_device *cdev;
689         dev_t devt;
690         int minor;
691         int error;
692
693         for (minor = 0; minor < MOUSEDEV_MINORS && mousedev_table[minor]; minor++);
694         if (minor == MOUSEDEV_MINORS) {
695                 printk(KERN_ERR "mousedev: no more free mousedev devices\n");
696                 return -ENFILE;
697         }
698
699         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
700         if (!mousedev)
701                 return -ENOMEM;
702
703         INIT_LIST_HEAD(&mousedev->client_list);
704         INIT_LIST_HEAD(&mousedev->mixdev_node);
705         init_waitqueue_head(&mousedev->wait);
706
707         mousedev->minor = minor;
708         mousedev->exist = 1;
709         mousedev->handle.dev = dev;
710         mousedev->handle.name = mousedev->name;
711         mousedev->handle.handler = handler;
712         mousedev->handle.private = mousedev;
713         sprintf(mousedev->name, "mouse%d", minor);
714
715         mousedev_table[minor] = mousedev;
716
717         devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor),
718
719         cdev = class_device_create(&input_class, &dev->cdev, devt,
720                                    dev->cdev.dev, mousedev->name);
721         if (IS_ERR(cdev)) {
722                 error = PTR_ERR(cdev);
723                 goto err_free_mousedev;
724         }
725
726         /* temporary symlink to keep userspace happy */
727         error = sysfs_create_link(&input_class.subsys.kobj,
728                                   &cdev->kobj, mousedev->name);
729         if (error)
730                 goto err_cdev_destroy;
731
732         error = input_register_handle(&mousedev->handle);
733         if (error)
734                 goto err_remove_link;
735
736         error = mixdev_add_device(mousedev);
737         if (error)
738                 goto err_unregister_handle;
739
740         return 0;
741
742  err_unregister_handle:
743         input_unregister_handle(&mousedev->handle);
744  err_remove_link:
745         sysfs_remove_link(&input_class.subsys.kobj, mousedev->name);
746  err_cdev_destroy:
747         class_device_destroy(&input_class, devt);
748  err_free_mousedev:
749         mousedev_table[minor] = NULL;
750         kfree(mousedev);
751         return error;
752 }
753
754 static void mousedev_disconnect(struct input_handle *handle)
755 {
756         struct mousedev *mousedev = handle->private;
757         struct mousedev_client *client;
758
759         input_unregister_handle(handle);
760
761         sysfs_remove_link(&input_class.subsys.kobj, mousedev->name);
762         class_device_destroy(&input_class,
763                         MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + mousedev->minor));
764         mousedev->exist = 0;
765
766         mixdev_remove_device(mousedev);
767
768         if (mousedev->open) {
769                 input_close_device(handle);
770                 list_for_each_entry(client, &mousedev->client_list, node)
771                         kill_fasync(&client->fasync, SIGIO, POLL_HUP);
772                 wake_up_interruptible(&mousedev->wait);
773         } else
774                 mousedev_free(mousedev);
775 }
776
777 static const struct input_device_id mousedev_ids[] = {
778         {
779                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT | INPUT_DEVICE_ID_MATCH_RELBIT,
780                 .evbit = { BIT(EV_KEY) | BIT(EV_REL) },
781                 .keybit = { [LONG(BTN_LEFT)] = BIT(BTN_LEFT) },
782                 .relbit = { BIT(REL_X) | BIT(REL_Y) },
783         },      /* A mouse like device, at least one button, two relative axes */
784         {
785                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_RELBIT,
786                 .evbit = { BIT(EV_KEY) | BIT(EV_REL) },
787                 .relbit = { BIT(REL_WHEEL) },
788         },      /* A separate scrollwheel */
789         {
790                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
791                 .evbit = { BIT(EV_KEY) | BIT(EV_ABS) },
792                 .keybit = { [LONG(BTN_TOUCH)] = BIT(BTN_TOUCH) },
793                 .absbit = { BIT(ABS_X) | BIT(ABS_Y) },
794         },      /* A tablet like device, at least touch detection, two absolute axes */
795         {
796                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT | INPUT_DEVICE_ID_MATCH_ABSBIT,
797                 .evbit = { BIT(EV_KEY) | BIT(EV_ABS) },
798                 .keybit = { [LONG(BTN_TOOL_FINGER)] = BIT(BTN_TOOL_FINGER) },
799                 .absbit = { BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE) | BIT(ABS_TOOL_WIDTH) },
800         },      /* A touchpad */
801
802         { },    /* Terminating entry */
803 };
804
805 MODULE_DEVICE_TABLE(input, mousedev_ids);
806
807 static struct input_handler mousedev_handler = {
808         .event =        mousedev_event,
809         .connect =      mousedev_connect,
810         .disconnect =   mousedev_disconnect,
811         .fops =         &mousedev_fops,
812         .minor =        MOUSEDEV_MINOR_BASE,
813         .name =         "mousedev",
814         .id_table =     mousedev_ids,
815 };
816
817 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
818 static struct miscdevice psaux_mouse = {
819         PSMOUSE_MINOR, "psaux", &mousedev_fops
820 };
821 static int psaux_registered;
822 #endif
823
824 static int __init mousedev_init(void)
825 {
826         struct class_device *cdev;
827         int error;
828
829         error = input_register_handler(&mousedev_handler);
830         if (error)
831                 return error;
832
833         memset(&mousedev_mix, 0, sizeof(struct mousedev));
834         INIT_LIST_HEAD(&mousedev_mix.client_list);
835         init_waitqueue_head(&mousedev_mix.wait);
836         mousedev_table[MOUSEDEV_MIX] = &mousedev_mix;
837         mousedev_mix.exist = 1;
838         mousedev_mix.minor = MOUSEDEV_MIX;
839
840         cdev = class_device_create(&input_class, NULL,
841                         MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + MOUSEDEV_MIX), NULL, "mice");
842         if (IS_ERR(cdev)) {
843                 input_unregister_handler(&mousedev_handler);
844                 return PTR_ERR(cdev);
845         }
846
847 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
848         error = misc_register(&psaux_mouse);
849         if (error)
850                 printk(KERN_WARNING "mice: could not register psaux device, "
851                         "error: %d\n", error);
852         else
853                 psaux_registered = 1;
854 #endif
855
856         printk(KERN_INFO "mice: PS/2 mouse device common for all mice\n");
857
858         return 0;
859 }
860
861 static void __exit mousedev_exit(void)
862 {
863 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
864         if (psaux_registered)
865                 misc_deregister(&psaux_mouse);
866 #endif
867         class_device_destroy(&input_class,
868                         MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + MOUSEDEV_MIX));
869         input_unregister_handler(&mousedev_handler);
870 }
871
872 module_init(mousedev_init);
873 module_exit(mousedev_exit);