Merge commit 'v2.6.35-rc1' into amd-iommu/2.6.35
[pandora-kernel.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/sched.h>
17 #include <linux/slab.h>
18 #include <linux/poll.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/input.h>
22 #include <linux/random.h>
23 #include <linux/major.h>
24 #include <linux/device.h>
25 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
26 #include <linux/miscdevice.h>
27 #endif
28
29 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
30 MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces");
31 MODULE_LICENSE("GPL");
32
33 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X
34 #define CONFIG_INPUT_MOUSEDEV_SCREEN_X  1024
35 #endif
36 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y
37 #define CONFIG_INPUT_MOUSEDEV_SCREEN_Y  768
38 #endif
39
40 static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
41 module_param(xres, uint, 0644);
42 MODULE_PARM_DESC(xres, "Horizontal screen resolution");
43
44 static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
45 module_param(yres, uint, 0644);
46 MODULE_PARM_DESC(yres, "Vertical screen resolution");
47
48 static unsigned tap_time = 200;
49 module_param(tap_time, uint, 0644);
50 MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)");
51
52 struct mousedev_hw_data {
53         int dx, dy, dz;
54         int x, y;
55         int abs_event;
56         unsigned long buttons;
57 };
58
59 struct mousedev {
60         int exist;
61         int open;
62         int minor;
63         struct input_handle handle;
64         wait_queue_head_t wait;
65         struct list_head client_list;
66         spinlock_t client_lock; /* protects client_list */
67         struct mutex mutex;
68         struct device dev;
69
70         struct list_head mixdev_node;
71         int mixdev_open;
72
73         struct mousedev_hw_data packet;
74         unsigned int pkt_count;
75         int old_x[4], old_y[4];
76         int frac_dx, frac_dy;
77         unsigned long touch;
78 };
79
80 enum mousedev_emul {
81         MOUSEDEV_EMUL_PS2,
82         MOUSEDEV_EMUL_IMPS,
83         MOUSEDEV_EMUL_EXPS
84 };
85
86 struct mousedev_motion {
87         int dx, dy, dz;
88         unsigned long buttons;
89 };
90
91 #define PACKET_QUEUE_LEN        16
92 struct mousedev_client {
93         struct fasync_struct *fasync;
94         struct mousedev *mousedev;
95         struct list_head node;
96
97         struct mousedev_motion packets[PACKET_QUEUE_LEN];
98         unsigned int head, tail;
99         spinlock_t packet_lock;
100         int pos_x, pos_y;
101
102         signed char ps2[6];
103         unsigned char ready, buffer, bufsiz;
104         unsigned char imexseq, impsseq;
105         enum mousedev_emul mode;
106         unsigned long last_buttons;
107 };
108
109 #define MOUSEDEV_SEQ_LEN        6
110
111 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
112 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
113
114 static struct input_handler mousedev_handler;
115
116 static struct mousedev *mousedev_table[MOUSEDEV_MINORS];
117 static DEFINE_MUTEX(mousedev_table_mutex);
118 static struct mousedev *mousedev_mix;
119 static LIST_HEAD(mousedev_mix_list);
120
121 static void mixdev_open_devices(void);
122 static void mixdev_close_devices(void);
123
124 #define fx(i)  (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
125 #define fy(i)  (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
126
127 static void mousedev_touchpad_event(struct input_dev *dev,
128                                     struct mousedev *mousedev,
129                                     unsigned int code, int value)
130 {
131         int size, tmp;
132         enum { FRACTION_DENOM = 128 };
133
134         switch (code) {
135
136         case ABS_X:
137                 fx(0) = value;
138                 if (mousedev->touch && mousedev->pkt_count >= 2) {
139                         size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
140                         if (size == 0)
141                                 size = 256 * 2;
142                         tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size;
143                         tmp += mousedev->frac_dx;
144                         mousedev->packet.dx = tmp / FRACTION_DENOM;
145                         mousedev->frac_dx =
146                                 tmp - mousedev->packet.dx * FRACTION_DENOM;
147                 }
148                 break;
149
150         case ABS_Y:
151                 fy(0) = value;
152                 if (mousedev->touch && mousedev->pkt_count >= 2) {
153                         /* use X size to keep the same scale */
154                         size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
155                         if (size == 0)
156                                 size = 256 * 2;
157                         tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
158                         tmp += mousedev->frac_dy;
159                         mousedev->packet.dy = tmp / FRACTION_DENOM;
160                         mousedev->frac_dy = tmp -
161                                 mousedev->packet.dy * FRACTION_DENOM;
162                 }
163                 break;
164         }
165 }
166
167 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
168                                 unsigned int code, int value)
169 {
170         int size;
171
172         switch (code) {
173
174         case ABS_X:
175                 size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
176                 if (size == 0)
177                         size = xres ? : 1;
178                 if (value > dev->absmax[ABS_X])
179                         value = dev->absmax[ABS_X];
180                 if (value < dev->absmin[ABS_X])
181                         value = dev->absmin[ABS_X];
182                 mousedev->packet.x =
183                         ((value - dev->absmin[ABS_X]) * xres) / size;
184                 mousedev->packet.abs_event = 1;
185                 break;
186
187         case ABS_Y:
188                 size = dev->absmax[ABS_Y] - dev->absmin[ABS_Y];
189                 if (size == 0)
190                         size = yres ? : 1;
191                 if (value > dev->absmax[ABS_Y])
192                         value = dev->absmax[ABS_Y];
193                 if (value < dev->absmin[ABS_Y])
194                         value = dev->absmin[ABS_Y];
195                 mousedev->packet.y = yres -
196                         ((value - dev->absmin[ABS_Y]) * yres) / size;
197                 mousedev->packet.abs_event = 1;
198                 break;
199         }
200 }
201
202 static void mousedev_rel_event(struct mousedev *mousedev,
203                                 unsigned int code, int value)
204 {
205         switch (code) {
206         case REL_X:
207                 mousedev->packet.dx += value;
208                 break;
209
210         case REL_Y:
211                 mousedev->packet.dy -= value;
212                 break;
213
214         case REL_WHEEL:
215                 mousedev->packet.dz -= value;
216                 break;
217         }
218 }
219
220 static void mousedev_key_event(struct mousedev *mousedev,
221                                 unsigned int code, int value)
222 {
223         int index;
224
225         switch (code) {
226
227         case BTN_TOUCH:
228         case BTN_0:
229         case BTN_LEFT:          index = 0; break;
230
231         case BTN_STYLUS:
232         case BTN_1:
233         case BTN_RIGHT:         index = 1; break;
234
235         case BTN_2:
236         case BTN_FORWARD:
237         case BTN_STYLUS2:
238         case BTN_MIDDLE:        index = 2; break;
239
240         case BTN_3:
241         case BTN_BACK:
242         case BTN_SIDE:          index = 3; break;
243
244         case BTN_4:
245         case BTN_EXTRA:         index = 4; break;
246
247         default:                return;
248         }
249
250         if (value) {
251                 set_bit(index, &mousedev->packet.buttons);
252                 set_bit(index, &mousedev_mix->packet.buttons);
253         } else {
254                 clear_bit(index, &mousedev->packet.buttons);
255                 clear_bit(index, &mousedev_mix->packet.buttons);
256         }
257 }
258
259 static void mousedev_notify_readers(struct mousedev *mousedev,
260                                     struct mousedev_hw_data *packet)
261 {
262         struct mousedev_client *client;
263         struct mousedev_motion *p;
264         unsigned int new_head;
265         int wake_readers = 0;
266
267         rcu_read_lock();
268         list_for_each_entry_rcu(client, &mousedev->client_list, node) {
269
270                 /* Just acquire the lock, interrupts already disabled */
271                 spin_lock(&client->packet_lock);
272
273                 p = &client->packets[client->head];
274                 if (client->ready && p->buttons != mousedev->packet.buttons) {
275                         new_head = (client->head + 1) % PACKET_QUEUE_LEN;
276                         if (new_head != client->tail) {
277                                 p = &client->packets[client->head = new_head];
278                                 memset(p, 0, sizeof(struct mousedev_motion));
279                         }
280                 }
281
282                 if (packet->abs_event) {
283                         p->dx += packet->x - client->pos_x;
284                         p->dy += packet->y - client->pos_y;
285                         client->pos_x = packet->x;
286                         client->pos_y = packet->y;
287                 }
288
289                 client->pos_x += packet->dx;
290                 client->pos_x = client->pos_x < 0 ?
291                         0 : (client->pos_x >= xres ? xres : client->pos_x);
292                 client->pos_y += packet->dy;
293                 client->pos_y = client->pos_y < 0 ?
294                         0 : (client->pos_y >= yres ? yres : client->pos_y);
295
296                 p->dx += packet->dx;
297                 p->dy += packet->dy;
298                 p->dz += packet->dz;
299                 p->buttons = mousedev->packet.buttons;
300
301                 if (p->dx || p->dy || p->dz ||
302                     p->buttons != client->last_buttons)
303                         client->ready = 1;
304
305                 spin_unlock(&client->packet_lock);
306
307                 if (client->ready) {
308                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
309                         wake_readers = 1;
310                 }
311         }
312         rcu_read_unlock();
313
314         if (wake_readers)
315                 wake_up_interruptible(&mousedev->wait);
316 }
317
318 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
319 {
320         if (!value) {
321                 if (mousedev->touch &&
322                     time_before(jiffies,
323                                 mousedev->touch + msecs_to_jiffies(tap_time))) {
324                         /*
325                          * Toggle left button to emulate tap.
326                          * We rely on the fact that mousedev_mix always has 0
327                          * motion packet so we won't mess current position.
328                          */
329                         set_bit(0, &mousedev->packet.buttons);
330                         set_bit(0, &mousedev_mix->packet.buttons);
331                         mousedev_notify_readers(mousedev, &mousedev_mix->packet);
332                         mousedev_notify_readers(mousedev_mix,
333                                                 &mousedev_mix->packet);
334                         clear_bit(0, &mousedev->packet.buttons);
335                         clear_bit(0, &mousedev_mix->packet.buttons);
336                 }
337                 mousedev->touch = mousedev->pkt_count = 0;
338                 mousedev->frac_dx = 0;
339                 mousedev->frac_dy = 0;
340
341         } else if (!mousedev->touch)
342                 mousedev->touch = jiffies;
343 }
344
345 static void mousedev_event(struct input_handle *handle,
346                            unsigned int type, unsigned int code, int value)
347 {
348         struct mousedev *mousedev = handle->private;
349
350         switch (type) {
351
352         case EV_ABS:
353                 /* Ignore joysticks */
354                 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
355                         return;
356
357                 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
358                         mousedev_touchpad_event(handle->dev,
359                                                 mousedev, code, value);
360                 else
361                         mousedev_abs_event(handle->dev, mousedev, code, value);
362
363                 break;
364
365         case EV_REL:
366                 mousedev_rel_event(mousedev, code, value);
367                 break;
368
369         case EV_KEY:
370                 if (value != 2) {
371                         if (code == BTN_TOUCH &&
372                             test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
373                                 mousedev_touchpad_touch(mousedev, value);
374                         else
375                                 mousedev_key_event(mousedev, code, value);
376                 }
377                 break;
378
379         case EV_SYN:
380                 if (code == SYN_REPORT) {
381                         if (mousedev->touch) {
382                                 mousedev->pkt_count++;
383                                 /*
384                                  * Input system eats duplicate events,
385                                  * but we need all of them to do correct
386                                  * averaging so apply present one forward
387                                  */
388                                 fx(0) = fx(1);
389                                 fy(0) = fy(1);
390                         }
391
392                         mousedev_notify_readers(mousedev, &mousedev->packet);
393                         mousedev_notify_readers(mousedev_mix, &mousedev->packet);
394
395                         mousedev->packet.dx = mousedev->packet.dy =
396                                 mousedev->packet.dz = 0;
397                         mousedev->packet.abs_event = 0;
398                 }
399                 break;
400         }
401 }
402
403 static int mousedev_fasync(int fd, struct file *file, int on)
404 {
405         struct mousedev_client *client = file->private_data;
406
407         return fasync_helper(fd, file, on, &client->fasync);
408 }
409
410 static void mousedev_free(struct device *dev)
411 {
412         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
413
414         input_put_device(mousedev->handle.dev);
415         kfree(mousedev);
416 }
417
418 static int mousedev_open_device(struct mousedev *mousedev)
419 {
420         int retval;
421
422         retval = mutex_lock_interruptible(&mousedev->mutex);
423         if (retval)
424                 return retval;
425
426         if (mousedev->minor == MOUSEDEV_MIX)
427                 mixdev_open_devices();
428         else if (!mousedev->exist)
429                 retval = -ENODEV;
430         else if (!mousedev->open++) {
431                 retval = input_open_device(&mousedev->handle);
432                 if (retval)
433                         mousedev->open--;
434         }
435
436         mutex_unlock(&mousedev->mutex);
437         return retval;
438 }
439
440 static void mousedev_close_device(struct mousedev *mousedev)
441 {
442         mutex_lock(&mousedev->mutex);
443
444         if (mousedev->minor == MOUSEDEV_MIX)
445                 mixdev_close_devices();
446         else if (mousedev->exist && !--mousedev->open)
447                 input_close_device(&mousedev->handle);
448
449         mutex_unlock(&mousedev->mutex);
450 }
451
452 /*
453  * Open all available devices so they can all be multiplexed in one.
454  * stream. Note that this function is called with mousedev_mix->mutex
455  * held.
456  */
457 static void mixdev_open_devices(void)
458 {
459         struct mousedev *mousedev;
460
461         if (mousedev_mix->open++)
462                 return;
463
464         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
465                 if (!mousedev->mixdev_open) {
466                         if (mousedev_open_device(mousedev))
467                                 continue;
468
469                         mousedev->mixdev_open = 1;
470                 }
471         }
472 }
473
474 /*
475  * Close all devices that were opened as part of multiplexed
476  * device. Note that this function is called with mousedev_mix->mutex
477  * held.
478  */
479 static void mixdev_close_devices(void)
480 {
481         struct mousedev *mousedev;
482
483         if (--mousedev_mix->open)
484                 return;
485
486         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
487                 if (mousedev->mixdev_open) {
488                         mousedev->mixdev_open = 0;
489                         mousedev_close_device(mousedev);
490                 }
491         }
492 }
493
494
495 static void mousedev_attach_client(struct mousedev *mousedev,
496                                    struct mousedev_client *client)
497 {
498         spin_lock(&mousedev->client_lock);
499         list_add_tail_rcu(&client->node, &mousedev->client_list);
500         spin_unlock(&mousedev->client_lock);
501         synchronize_rcu();
502 }
503
504 static void mousedev_detach_client(struct mousedev *mousedev,
505                                    struct mousedev_client *client)
506 {
507         spin_lock(&mousedev->client_lock);
508         list_del_rcu(&client->node);
509         spin_unlock(&mousedev->client_lock);
510         synchronize_rcu();
511 }
512
513 static int mousedev_release(struct inode *inode, struct file *file)
514 {
515         struct mousedev_client *client = file->private_data;
516         struct mousedev *mousedev = client->mousedev;
517
518         mousedev_detach_client(mousedev, client);
519         kfree(client);
520
521         mousedev_close_device(mousedev);
522         put_device(&mousedev->dev);
523
524         return 0;
525 }
526
527 static int mousedev_open(struct inode *inode, struct file *file)
528 {
529         struct mousedev_client *client;
530         struct mousedev *mousedev;
531         int error;
532         int i;
533
534 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
535         if (imajor(inode) == MISC_MAJOR)
536                 i = MOUSEDEV_MIX;
537         else
538 #endif
539                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
540
541         if (i >= MOUSEDEV_MINORS)
542                 return -ENODEV;
543
544         error = mutex_lock_interruptible(&mousedev_table_mutex);
545         if (error) {
546                 return error;
547         }
548         mousedev = mousedev_table[i];
549         if (mousedev)
550                 get_device(&mousedev->dev);
551         mutex_unlock(&mousedev_table_mutex);
552
553         if (!mousedev) {
554                 return -ENODEV;
555         }
556
557         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
558         if (!client) {
559                 error = -ENOMEM;
560                 goto err_put_mousedev;
561         }
562
563         spin_lock_init(&client->packet_lock);
564         client->pos_x = xres / 2;
565         client->pos_y = yres / 2;
566         client->mousedev = mousedev;
567         mousedev_attach_client(mousedev, client);
568
569         error = mousedev_open_device(mousedev);
570         if (error)
571                 goto err_free_client;
572
573         file->private_data = client;
574         return 0;
575
576  err_free_client:
577         mousedev_detach_client(mousedev, client);
578         kfree(client);
579  err_put_mousedev:
580         put_device(&mousedev->dev);
581         return error;
582 }
583
584 static inline int mousedev_limit_delta(int delta, int limit)
585 {
586         return delta > limit ? limit : (delta < -limit ? -limit : delta);
587 }
588
589 static void mousedev_packet(struct mousedev_client *client,
590                             signed char *ps2_data)
591 {
592         struct mousedev_motion *p = &client->packets[client->tail];
593
594         ps2_data[0] = 0x08 |
595                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
596         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
597         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
598         p->dx -= ps2_data[1];
599         p->dy -= ps2_data[2];
600
601         switch (client->mode) {
602         case MOUSEDEV_EMUL_EXPS:
603                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
604                 p->dz -= ps2_data[3];
605                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
606                 client->bufsiz = 4;
607                 break;
608
609         case MOUSEDEV_EMUL_IMPS:
610                 ps2_data[0] |=
611                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
612                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
613                 p->dz -= ps2_data[3];
614                 client->bufsiz = 4;
615                 break;
616
617         case MOUSEDEV_EMUL_PS2:
618         default:
619                 ps2_data[0] |=
620                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
621                 p->dz = 0;
622                 client->bufsiz = 3;
623                 break;
624         }
625
626         if (!p->dx && !p->dy && !p->dz) {
627                 if (client->tail == client->head) {
628                         client->ready = 0;
629                         client->last_buttons = p->buttons;
630                 } else
631                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
632         }
633 }
634
635 static void mousedev_generate_response(struct mousedev_client *client,
636                                         int command)
637 {
638         client->ps2[0] = 0xfa; /* ACK */
639
640         switch (command) {
641
642         case 0xeb: /* Poll */
643                 mousedev_packet(client, &client->ps2[1]);
644                 client->bufsiz++; /* account for leading ACK */
645                 break;
646
647         case 0xf2: /* Get ID */
648                 switch (client->mode) {
649                 case MOUSEDEV_EMUL_PS2:
650                         client->ps2[1] = 0;
651                         break;
652                 case MOUSEDEV_EMUL_IMPS:
653                         client->ps2[1] = 3;
654                         break;
655                 case MOUSEDEV_EMUL_EXPS:
656                         client->ps2[1] = 4;
657                         break;
658                 }
659                 client->bufsiz = 2;
660                 break;
661
662         case 0xe9: /* Get info */
663                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
664                 client->bufsiz = 4;
665                 break;
666
667         case 0xff: /* Reset */
668                 client->impsseq = client->imexseq = 0;
669                 client->mode = MOUSEDEV_EMUL_PS2;
670                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
671                 client->bufsiz = 3;
672                 break;
673
674         default:
675                 client->bufsiz = 1;
676                 break;
677         }
678         client->buffer = client->bufsiz;
679 }
680
681 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
682                                 size_t count, loff_t *ppos)
683 {
684         struct mousedev_client *client = file->private_data;
685         unsigned char c;
686         unsigned int i;
687
688         for (i = 0; i < count; i++) {
689
690                 if (get_user(c, buffer + i))
691                         return -EFAULT;
692
693                 spin_lock_irq(&client->packet_lock);
694
695                 if (c == mousedev_imex_seq[client->imexseq]) {
696                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
697                                 client->imexseq = 0;
698                                 client->mode = MOUSEDEV_EMUL_EXPS;
699                         }
700                 } else
701                         client->imexseq = 0;
702
703                 if (c == mousedev_imps_seq[client->impsseq]) {
704                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
705                                 client->impsseq = 0;
706                                 client->mode = MOUSEDEV_EMUL_IMPS;
707                         }
708                 } else
709                         client->impsseq = 0;
710
711                 mousedev_generate_response(client, c);
712
713                 spin_unlock_irq(&client->packet_lock);
714         }
715
716         kill_fasync(&client->fasync, SIGIO, POLL_IN);
717         wake_up_interruptible(&client->mousedev->wait);
718
719         return count;
720 }
721
722 static ssize_t mousedev_read(struct file *file, char __user *buffer,
723                              size_t count, loff_t *ppos)
724 {
725         struct mousedev_client *client = file->private_data;
726         struct mousedev *mousedev = client->mousedev;
727         signed char data[sizeof(client->ps2)];
728         int retval = 0;
729
730         if (!client->ready && !client->buffer && mousedev->exist &&
731             (file->f_flags & O_NONBLOCK))
732                 return -EAGAIN;
733
734         retval = wait_event_interruptible(mousedev->wait,
735                         !mousedev->exist || client->ready || client->buffer);
736         if (retval)
737                 return retval;
738
739         if (!mousedev->exist)
740                 return -ENODEV;
741
742         spin_lock_irq(&client->packet_lock);
743
744         if (!client->buffer && client->ready) {
745                 mousedev_packet(client, client->ps2);
746                 client->buffer = client->bufsiz;
747         }
748
749         if (count > client->buffer)
750                 count = client->buffer;
751
752         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
753         client->buffer -= count;
754
755         spin_unlock_irq(&client->packet_lock);
756
757         if (copy_to_user(buffer, data, count))
758                 return -EFAULT;
759
760         return count;
761 }
762
763 /* No kernel lock - fine */
764 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
765 {
766         struct mousedev_client *client = file->private_data;
767         struct mousedev *mousedev = client->mousedev;
768
769         poll_wait(file, &mousedev->wait, wait);
770         return ((client->ready || client->buffer) ? (POLLIN | POLLRDNORM) : 0) |
771                 (mousedev->exist ? 0 : (POLLHUP | POLLERR));
772 }
773
774 static const struct file_operations mousedev_fops = {
775         .owner =        THIS_MODULE,
776         .read =         mousedev_read,
777         .write =        mousedev_write,
778         .poll =         mousedev_poll,
779         .open =         mousedev_open,
780         .release =      mousedev_release,
781         .fasync =       mousedev_fasync,
782 };
783
784 static int mousedev_install_chrdev(struct mousedev *mousedev)
785 {
786         mousedev_table[mousedev->minor] = mousedev;
787         return 0;
788 }
789
790 static void mousedev_remove_chrdev(struct mousedev *mousedev)
791 {
792         mutex_lock(&mousedev_table_mutex);
793         mousedev_table[mousedev->minor] = NULL;
794         mutex_unlock(&mousedev_table_mutex);
795 }
796
797 /*
798  * Mark device non-existent. This disables writes, ioctls and
799  * prevents new users from opening the device. Already posted
800  * blocking reads will stay, however new ones will fail.
801  */
802 static void mousedev_mark_dead(struct mousedev *mousedev)
803 {
804         mutex_lock(&mousedev->mutex);
805         mousedev->exist = 0;
806         mutex_unlock(&mousedev->mutex);
807 }
808
809 /*
810  * Wake up users waiting for IO so they can disconnect from
811  * dead device.
812  */
813 static void mousedev_hangup(struct mousedev *mousedev)
814 {
815         struct mousedev_client *client;
816
817         spin_lock(&mousedev->client_lock);
818         list_for_each_entry(client, &mousedev->client_list, node)
819                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
820         spin_unlock(&mousedev->client_lock);
821
822         wake_up_interruptible(&mousedev->wait);
823 }
824
825 static void mousedev_cleanup(struct mousedev *mousedev)
826 {
827         struct input_handle *handle = &mousedev->handle;
828
829         mousedev_mark_dead(mousedev);
830         mousedev_hangup(mousedev);
831         mousedev_remove_chrdev(mousedev);
832
833         /* mousedev is marked dead so no one else accesses mousedev->open */
834         if (mousedev->open)
835                 input_close_device(handle);
836 }
837
838 static struct mousedev *mousedev_create(struct input_dev *dev,
839                                         struct input_handler *handler,
840                                         int minor)
841 {
842         struct mousedev *mousedev;
843         int error;
844
845         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
846         if (!mousedev) {
847                 error = -ENOMEM;
848                 goto err_out;
849         }
850
851         INIT_LIST_HEAD(&mousedev->client_list);
852         INIT_LIST_HEAD(&mousedev->mixdev_node);
853         spin_lock_init(&mousedev->client_lock);
854         mutex_init(&mousedev->mutex);
855         lockdep_set_subclass(&mousedev->mutex,
856                              minor == MOUSEDEV_MIX ? MOUSEDEV_MIX : 0);
857         init_waitqueue_head(&mousedev->wait);
858
859         if (minor == MOUSEDEV_MIX)
860                 dev_set_name(&mousedev->dev, "mice");
861         else
862                 dev_set_name(&mousedev->dev, "mouse%d", minor);
863
864         mousedev->minor = minor;
865         mousedev->exist = 1;
866         mousedev->handle.dev = input_get_device(dev);
867         mousedev->handle.name = dev_name(&mousedev->dev);
868         mousedev->handle.handler = handler;
869         mousedev->handle.private = mousedev;
870
871         mousedev->dev.class = &input_class;
872         if (dev)
873                 mousedev->dev.parent = &dev->dev;
874         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
875         mousedev->dev.release = mousedev_free;
876         device_initialize(&mousedev->dev);
877
878         if (minor != MOUSEDEV_MIX) {
879                 error = input_register_handle(&mousedev->handle);
880                 if (error)
881                         goto err_free_mousedev;
882         }
883
884         error = mousedev_install_chrdev(mousedev);
885         if (error)
886                 goto err_unregister_handle;
887
888         error = device_add(&mousedev->dev);
889         if (error)
890                 goto err_cleanup_mousedev;
891
892         return mousedev;
893
894  err_cleanup_mousedev:
895         mousedev_cleanup(mousedev);
896  err_unregister_handle:
897         if (minor != MOUSEDEV_MIX)
898                 input_unregister_handle(&mousedev->handle);
899  err_free_mousedev:
900         put_device(&mousedev->dev);
901  err_out:
902         return ERR_PTR(error);
903 }
904
905 static void mousedev_destroy(struct mousedev *mousedev)
906 {
907         device_del(&mousedev->dev);
908         mousedev_cleanup(mousedev);
909         if (mousedev->minor != MOUSEDEV_MIX)
910                 input_unregister_handle(&mousedev->handle);
911         put_device(&mousedev->dev);
912 }
913
914 static int mixdev_add_device(struct mousedev *mousedev)
915 {
916         int retval;
917
918         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
919         if (retval)
920                 return retval;
921
922         if (mousedev_mix->open) {
923                 retval = mousedev_open_device(mousedev);
924                 if (retval)
925                         goto out;
926
927                 mousedev->mixdev_open = 1;
928         }
929
930         get_device(&mousedev->dev);
931         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
932
933  out:
934         mutex_unlock(&mousedev_mix->mutex);
935         return retval;
936 }
937
938 static void mixdev_remove_device(struct mousedev *mousedev)
939 {
940         mutex_lock(&mousedev_mix->mutex);
941
942         if (mousedev->mixdev_open) {
943                 mousedev->mixdev_open = 0;
944                 mousedev_close_device(mousedev);
945         }
946
947         list_del_init(&mousedev->mixdev_node);
948         mutex_unlock(&mousedev_mix->mutex);
949
950         put_device(&mousedev->dev);
951 }
952
953 static int mousedev_connect(struct input_handler *handler,
954                             struct input_dev *dev,
955                             const struct input_device_id *id)
956 {
957         struct mousedev *mousedev;
958         int minor;
959         int error;
960
961         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
962                 if (!mousedev_table[minor])
963                         break;
964
965         if (minor == MOUSEDEV_MINORS) {
966                 printk(KERN_ERR "mousedev: no more free mousedev devices\n");
967                 return -ENFILE;
968         }
969
970         mousedev = mousedev_create(dev, handler, minor);
971         if (IS_ERR(mousedev))
972                 return PTR_ERR(mousedev);
973
974         error = mixdev_add_device(mousedev);
975         if (error) {
976                 mousedev_destroy(mousedev);
977                 return error;
978         }
979
980         return 0;
981 }
982
983 static void mousedev_disconnect(struct input_handle *handle)
984 {
985         struct mousedev *mousedev = handle->private;
986
987         mixdev_remove_device(mousedev);
988         mousedev_destroy(mousedev);
989 }
990
991 static const struct input_device_id mousedev_ids[] = {
992         {
993                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
994                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
995                                 INPUT_DEVICE_ID_MATCH_RELBIT,
996                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
997                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
998                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
999         },      /* A mouse like device, at least one button,
1000                    two relative axes */
1001         {
1002                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1003                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1004                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1005                 .relbit = { BIT_MASK(REL_WHEEL) },
1006         },      /* A separate scrollwheel */
1007         {
1008                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1009                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1010                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1011                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1012                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1013                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1014         },      /* A tablet like device, at least touch detection,
1015                    two absolute axes */
1016         {
1017                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1018                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1019                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1020                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1021                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1022                                 BIT_MASK(BTN_TOOL_FINGER) },
1023                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1024                                 BIT_MASK(ABS_PRESSURE) |
1025                                 BIT_MASK(ABS_TOOL_WIDTH) },
1026         },      /* A touchpad */
1027         {
1028                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1029                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1030                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1031                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1032                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1033                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1034         },      /* Mouse-like device with absolute X and Y but ordinary
1035                    clicks, like hp ILO2 High Performance mouse */
1036
1037         { },    /* Terminating entry */
1038 };
1039
1040 MODULE_DEVICE_TABLE(input, mousedev_ids);
1041
1042 static struct input_handler mousedev_handler = {
1043         .event =        mousedev_event,
1044         .connect =      mousedev_connect,
1045         .disconnect =   mousedev_disconnect,
1046         .fops =         &mousedev_fops,
1047         .minor =        MOUSEDEV_MINOR_BASE,
1048         .name =         "mousedev",
1049         .id_table =     mousedev_ids,
1050 };
1051
1052 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1053 static struct miscdevice psaux_mouse = {
1054         PSMOUSE_MINOR, "psaux", &mousedev_fops
1055 };
1056 static int psaux_registered;
1057 #endif
1058
1059 static int __init mousedev_init(void)
1060 {
1061         int error;
1062
1063         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1064         if (IS_ERR(mousedev_mix))
1065                 return PTR_ERR(mousedev_mix);
1066
1067         error = input_register_handler(&mousedev_handler);
1068         if (error) {
1069                 mousedev_destroy(mousedev_mix);
1070                 return error;
1071         }
1072
1073 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1074         error = misc_register(&psaux_mouse);
1075         if (error)
1076                 printk(KERN_WARNING "mice: could not register psaux device, "
1077                         "error: %d\n", error);
1078         else
1079                 psaux_registered = 1;
1080 #endif
1081
1082         printk(KERN_INFO "mice: PS/2 mouse device common for all mice\n");
1083
1084         return 0;
1085 }
1086
1087 static void __exit mousedev_exit(void)
1088 {
1089 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1090         if (psaux_registered)
1091                 misc_deregister(&psaux_mouse);
1092 #endif
1093         input_unregister_handler(&mousedev_handler);
1094         mousedev_destroy(mousedev_mix);
1095 }
1096
1097 module_init(mousedev_init);
1098 module_exit(mousedev_exit);