8137e50ded87de13d31d378557a68ba58d3cedb5
[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/smp_lock.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         char name[16];
64         struct input_handle handle;
65         wait_queue_head_t wait;
66         struct list_head client_list;
67         spinlock_t client_lock; /* protects client_list */
68         struct mutex mutex;
69         struct device dev;
70
71         struct list_head mixdev_node;
72         int mixdev_open;
73
74         struct mousedev_hw_data packet;
75         unsigned int pkt_count;
76         int old_x[4], old_y[4];
77         int frac_dx, frac_dy;
78         unsigned long touch;
79 };
80
81 enum mousedev_emul {
82         MOUSEDEV_EMUL_PS2,
83         MOUSEDEV_EMUL_IMPS,
84         MOUSEDEV_EMUL_EXPS
85 };
86
87 struct mousedev_motion {
88         int dx, dy, dz;
89         unsigned long buttons;
90 };
91
92 #define PACKET_QUEUE_LEN        16
93 struct mousedev_client {
94         struct fasync_struct *fasync;
95         struct mousedev *mousedev;
96         struct list_head node;
97
98         struct mousedev_motion packets[PACKET_QUEUE_LEN];
99         unsigned int head, tail;
100         spinlock_t packet_lock;
101         int pos_x, pos_y;
102
103         signed char ps2[6];
104         unsigned char ready, buffer, bufsiz;
105         unsigned char imexseq, impsseq;
106         enum mousedev_emul mode;
107         unsigned long last_buttons;
108 };
109
110 #define MOUSEDEV_SEQ_LEN        6
111
112 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
113 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
114
115 static struct input_handler mousedev_handler;
116
117 static struct mousedev *mousedev_table[MOUSEDEV_MINORS];
118 static DEFINE_MUTEX(mousedev_table_mutex);
119 static struct mousedev *mousedev_mix;
120 static LIST_HEAD(mousedev_mix_list);
121
122 static void mixdev_open_devices(void);
123 static void mixdev_close_devices(void);
124
125 #define fx(i)  (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
126 #define fy(i)  (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
127
128 static void mousedev_touchpad_event(struct input_dev *dev,
129                                     struct mousedev *mousedev,
130                                     unsigned int code, int value)
131 {
132         int size, tmp;
133         enum { FRACTION_DENOM = 128 };
134
135         switch (code) {
136
137         case ABS_X:
138                 fx(0) = value;
139                 if (mousedev->touch && mousedev->pkt_count >= 2) {
140                         size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
141                         if (size == 0)
142                                 size = 256 * 2;
143                         tmp = ((value - fx(2)) * 256 * FRACTION_DENOM) / size;
144                         tmp += mousedev->frac_dx;
145                         mousedev->packet.dx = tmp / FRACTION_DENOM;
146                         mousedev->frac_dx =
147                                 tmp - mousedev->packet.dx * FRACTION_DENOM;
148                 }
149                 break;
150
151         case ABS_Y:
152                 fy(0) = value;
153                 if (mousedev->touch && mousedev->pkt_count >= 2) {
154                         /* use X size to keep the same scale */
155                         size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
156                         if (size == 0)
157                                 size = 256 * 2;
158                         tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
159                         tmp += mousedev->frac_dy;
160                         mousedev->packet.dy = tmp / FRACTION_DENOM;
161                         mousedev->frac_dy = tmp -
162                                 mousedev->packet.dy * FRACTION_DENOM;
163                 }
164                 break;
165         }
166 }
167
168 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
169                                 unsigned int code, int value)
170 {
171         int size;
172
173         switch (code) {
174
175         case ABS_X:
176                 size = dev->absmax[ABS_X] - dev->absmin[ABS_X];
177                 if (size == 0)
178                         size = xres ? : 1;
179                 if (value > dev->absmax[ABS_X])
180                         value = dev->absmax[ABS_X];
181                 if (value < dev->absmin[ABS_X])
182                         value = dev->absmin[ABS_X];
183                 mousedev->packet.x =
184                         ((value - dev->absmin[ABS_X]) * xres) / size;
185                 mousedev->packet.abs_event = 1;
186                 break;
187
188         case ABS_Y:
189                 size = dev->absmax[ABS_Y] - dev->absmin[ABS_Y];
190                 if (size == 0)
191                         size = yres ? : 1;
192                 if (value > dev->absmax[ABS_Y])
193                         value = dev->absmax[ABS_Y];
194                 if (value < dev->absmin[ABS_Y])
195                         value = dev->absmin[ABS_Y];
196                 mousedev->packet.y = yres -
197                         ((value - dev->absmin[ABS_Y]) * yres) / size;
198                 mousedev->packet.abs_event = 1;
199                 break;
200         }
201 }
202
203 static void mousedev_rel_event(struct mousedev *mousedev,
204                                 unsigned int code, int value)
205 {
206         switch (code) {
207         case REL_X:
208                 mousedev->packet.dx += value;
209                 break;
210
211         case REL_Y:
212                 mousedev->packet.dy -= value;
213                 break;
214
215         case REL_WHEEL:
216                 mousedev->packet.dz -= value;
217                 break;
218         }
219 }
220
221 static void mousedev_key_event(struct mousedev *mousedev,
222                                 unsigned int code, int value)
223 {
224         int index;
225
226         switch (code) {
227
228         case BTN_TOUCH:
229         case BTN_0:
230         case BTN_LEFT:          index = 0; break;
231
232         case BTN_STYLUS:
233         case BTN_1:
234         case BTN_RIGHT:         index = 1; break;
235
236         case BTN_2:
237         case BTN_FORWARD:
238         case BTN_STYLUS2:
239         case BTN_MIDDLE:        index = 2; break;
240
241         case BTN_3:
242         case BTN_BACK:
243         case BTN_SIDE:          index = 3; break;
244
245         case BTN_4:
246         case BTN_EXTRA:         index = 4; break;
247
248         default:                return;
249         }
250
251         if (value) {
252                 set_bit(index, &mousedev->packet.buttons);
253                 set_bit(index, &mousedev_mix->packet.buttons);
254         } else {
255                 clear_bit(index, &mousedev->packet.buttons);
256                 clear_bit(index, &mousedev_mix->packet.buttons);
257         }
258 }
259
260 static void mousedev_notify_readers(struct mousedev *mousedev,
261                                     struct mousedev_hw_data *packet)
262 {
263         struct mousedev_client *client;
264         struct mousedev_motion *p;
265         unsigned int new_head;
266         int wake_readers = 0;
267
268         rcu_read_lock();
269         list_for_each_entry_rcu(client, &mousedev->client_list, node) {
270
271                 /* Just acquire the lock, interrupts already disabled */
272                 spin_lock(&client->packet_lock);
273
274                 p = &client->packets[client->head];
275                 if (client->ready && p->buttons != mousedev->packet.buttons) {
276                         new_head = (client->head + 1) % PACKET_QUEUE_LEN;
277                         if (new_head != client->tail) {
278                                 p = &client->packets[client->head = new_head];
279                                 memset(p, 0, sizeof(struct mousedev_motion));
280                         }
281                 }
282
283                 if (packet->abs_event) {
284                         p->dx += packet->x - client->pos_x;
285                         p->dy += packet->y - client->pos_y;
286                         client->pos_x = packet->x;
287                         client->pos_y = packet->y;
288                 }
289
290                 client->pos_x += packet->dx;
291                 client->pos_x = client->pos_x < 0 ?
292                         0 : (client->pos_x >= xres ? xres : client->pos_x);
293                 client->pos_y += packet->dy;
294                 client->pos_y = client->pos_y < 0 ?
295                         0 : (client->pos_y >= yres ? yres : client->pos_y);
296
297                 p->dx += packet->dx;
298                 p->dy += packet->dy;
299                 p->dz += packet->dz;
300                 p->buttons = mousedev->packet.buttons;
301
302                 if (p->dx || p->dy || p->dz ||
303                     p->buttons != client->last_buttons)
304                         client->ready = 1;
305
306                 spin_unlock(&client->packet_lock);
307
308                 if (client->ready) {
309                         kill_fasync(&client->fasync, SIGIO, POLL_IN);
310                         wake_readers = 1;
311                 }
312         }
313         rcu_read_unlock();
314
315         if (wake_readers)
316                 wake_up_interruptible(&mousedev->wait);
317 }
318
319 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
320 {
321         if (!value) {
322                 if (mousedev->touch &&
323                     time_before(jiffies,
324                                 mousedev->touch + msecs_to_jiffies(tap_time))) {
325                         /*
326                          * Toggle left button to emulate tap.
327                          * We rely on the fact that mousedev_mix always has 0
328                          * motion packet so we won't mess current position.
329                          */
330                         set_bit(0, &mousedev->packet.buttons);
331                         set_bit(0, &mousedev_mix->packet.buttons);
332                         mousedev_notify_readers(mousedev, &mousedev_mix->packet);
333                         mousedev_notify_readers(mousedev_mix,
334                                                 &mousedev_mix->packet);
335                         clear_bit(0, &mousedev->packet.buttons);
336                         clear_bit(0, &mousedev_mix->packet.buttons);
337                 }
338                 mousedev->touch = mousedev->pkt_count = 0;
339                 mousedev->frac_dx = 0;
340                 mousedev->frac_dy = 0;
341
342         } else if (!mousedev->touch)
343                 mousedev->touch = jiffies;
344 }
345
346 static void mousedev_event(struct input_handle *handle,
347                            unsigned int type, unsigned int code, int value)
348 {
349         struct mousedev *mousedev = handle->private;
350
351         switch (type) {
352
353         case EV_ABS:
354                 /* Ignore joysticks */
355                 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
356                         return;
357
358                 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
359                         mousedev_touchpad_event(handle->dev,
360                                                 mousedev, code, value);
361                 else
362                         mousedev_abs_event(handle->dev, mousedev, code, value);
363
364                 break;
365
366         case EV_REL:
367                 mousedev_rel_event(mousedev, code, value);
368                 break;
369
370         case EV_KEY:
371                 if (value != 2) {
372                         if (code == BTN_TOUCH &&
373                             test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
374                                 mousedev_touchpad_touch(mousedev, value);
375                         else
376                                 mousedev_key_event(mousedev, code, value);
377                 }
378                 break;
379
380         case EV_SYN:
381                 if (code == SYN_REPORT) {
382                         if (mousedev->touch) {
383                                 mousedev->pkt_count++;
384                                 /*
385                                  * Input system eats duplicate events,
386                                  * but we need all of them to do correct
387                                  * averaging so apply present one forward
388                                  */
389                                 fx(0) = fx(1);
390                                 fy(0) = fy(1);
391                         }
392
393                         mousedev_notify_readers(mousedev, &mousedev->packet);
394                         mousedev_notify_readers(mousedev_mix, &mousedev->packet);
395
396                         mousedev->packet.dx = mousedev->packet.dy =
397                                 mousedev->packet.dz = 0;
398                         mousedev->packet.abs_event = 0;
399                 }
400                 break;
401         }
402 }
403
404 static int mousedev_fasync(int fd, struct file *file, int on)
405 {
406         int retval;
407         struct mousedev_client *client = file->private_data;
408
409         retval = fasync_helper(fd, file, on, &client->fasync);
410
411         return retval < 0 ? retval : 0;
412 }
413
414 static void mousedev_free(struct device *dev)
415 {
416         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
417
418         input_put_device(mousedev->handle.dev);
419         kfree(mousedev);
420 }
421
422 static int mousedev_open_device(struct mousedev *mousedev)
423 {
424         int retval;
425
426         retval = mutex_lock_interruptible(&mousedev->mutex);
427         if (retval)
428                 return retval;
429
430         if (mousedev->minor == MOUSEDEV_MIX)
431                 mixdev_open_devices();
432         else if (!mousedev->exist)
433                 retval = -ENODEV;
434         else if (!mousedev->open++) {
435                 retval = input_open_device(&mousedev->handle);
436                 if (retval)
437                         mousedev->open--;
438         }
439
440         mutex_unlock(&mousedev->mutex);
441         return retval;
442 }
443
444 static void mousedev_close_device(struct mousedev *mousedev)
445 {
446         mutex_lock(&mousedev->mutex);
447
448         if (mousedev->minor == MOUSEDEV_MIX)
449                 mixdev_close_devices();
450         else if (mousedev->exist && !--mousedev->open)
451                 input_close_device(&mousedev->handle);
452
453         mutex_unlock(&mousedev->mutex);
454 }
455
456 /*
457  * Open all available devices so they can all be multiplexed in one.
458  * stream. Note that this function is called with mousedev_mix->mutex
459  * held.
460  */
461 static void mixdev_open_devices(void)
462 {
463         struct mousedev *mousedev;
464
465         if (mousedev_mix->open++)
466                 return;
467
468         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
469                 if (!mousedev->mixdev_open) {
470                         if (mousedev_open_device(mousedev))
471                                 continue;
472
473                         mousedev->mixdev_open = 1;
474                 }
475         }
476 }
477
478 /*
479  * Close all devices that were opened as part of multiplexed
480  * device. Note that this function is called with mousedev_mix->mutex
481  * held.
482  */
483 static void mixdev_close_devices(void)
484 {
485         struct mousedev *mousedev;
486
487         if (--mousedev_mix->open)
488                 return;
489
490         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
491                 if (mousedev->mixdev_open) {
492                         mousedev->mixdev_open = 0;
493                         mousedev_close_device(mousedev);
494                 }
495         }
496 }
497
498
499 static void mousedev_attach_client(struct mousedev *mousedev,
500                                    struct mousedev_client *client)
501 {
502         spin_lock(&mousedev->client_lock);
503         list_add_tail_rcu(&client->node, &mousedev->client_list);
504         spin_unlock(&mousedev->client_lock);
505         synchronize_rcu();
506 }
507
508 static void mousedev_detach_client(struct mousedev *mousedev,
509                                    struct mousedev_client *client)
510 {
511         spin_lock(&mousedev->client_lock);
512         list_del_rcu(&client->node);
513         spin_unlock(&mousedev->client_lock);
514         synchronize_rcu();
515 }
516
517 static int mousedev_release(struct inode *inode, struct file *file)
518 {
519         struct mousedev_client *client = file->private_data;
520         struct mousedev *mousedev = client->mousedev;
521
522         mousedev_fasync(-1, file, 0);
523         mousedev_detach_client(mousedev, client);
524         kfree(client);
525
526         mousedev_close_device(mousedev);
527         put_device(&mousedev->dev);
528
529         return 0;
530 }
531
532 static int mousedev_open(struct inode *inode, struct file *file)
533 {
534         struct mousedev_client *client;
535         struct mousedev *mousedev;
536         int error;
537         int i;
538
539 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
540         if (imajor(inode) == MISC_MAJOR)
541                 i = MOUSEDEV_MIX;
542         else
543 #endif
544                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
545
546         if (i >= MOUSEDEV_MINORS)
547                 return -ENODEV;
548
549         lock_kernel();
550         error = mutex_lock_interruptible(&mousedev_table_mutex);
551         if (error) {
552                 unlock_kernel();
553                 return error;
554         }
555         mousedev = mousedev_table[i];
556         if (mousedev)
557                 get_device(&mousedev->dev);
558         mutex_unlock(&mousedev_table_mutex);
559
560         if (!mousedev) {
561                 unlock_kernel();
562                 return -ENODEV;
563         }
564
565         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
566         if (!client) {
567                 error = -ENOMEM;
568                 goto err_put_mousedev;
569         }
570
571         spin_lock_init(&client->packet_lock);
572         client->pos_x = xres / 2;
573         client->pos_y = yres / 2;
574         client->mousedev = mousedev;
575         mousedev_attach_client(mousedev, client);
576
577         error = mousedev_open_device(mousedev);
578         if (error)
579                 goto err_free_client;
580
581         file->private_data = client;
582         unlock_kernel();
583         return 0;
584
585  err_free_client:
586         mousedev_detach_client(mousedev, client);
587         kfree(client);
588  err_put_mousedev:
589         put_device(&mousedev->dev);
590         unlock_kernel();
591         return error;
592 }
593
594 static inline int mousedev_limit_delta(int delta, int limit)
595 {
596         return delta > limit ? limit : (delta < -limit ? -limit : delta);
597 }
598
599 static void mousedev_packet(struct mousedev_client *client,
600                             signed char *ps2_data)
601 {
602         struct mousedev_motion *p = &client->packets[client->tail];
603
604         ps2_data[0] = 0x08 |
605                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
606         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
607         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
608         p->dx -= ps2_data[1];
609         p->dy -= ps2_data[2];
610
611         switch (client->mode) {
612         case MOUSEDEV_EMUL_EXPS:
613                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
614                 p->dz -= ps2_data[3];
615                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
616                 client->bufsiz = 4;
617                 break;
618
619         case MOUSEDEV_EMUL_IMPS:
620                 ps2_data[0] |=
621                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
622                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
623                 p->dz -= ps2_data[3];
624                 client->bufsiz = 4;
625                 break;
626
627         case MOUSEDEV_EMUL_PS2:
628         default:
629                 ps2_data[0] |=
630                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
631                 p->dz = 0;
632                 client->bufsiz = 3;
633                 break;
634         }
635
636         if (!p->dx && !p->dy && !p->dz) {
637                 if (client->tail == client->head) {
638                         client->ready = 0;
639                         client->last_buttons = p->buttons;
640                 } else
641                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
642         }
643 }
644
645 static void mousedev_generate_response(struct mousedev_client *client,
646                                         int command)
647 {
648         client->ps2[0] = 0xfa; /* ACK */
649
650         switch (command) {
651
652         case 0xeb: /* Poll */
653                 mousedev_packet(client, &client->ps2[1]);
654                 client->bufsiz++; /* account for leading ACK */
655                 break;
656
657         case 0xf2: /* Get ID */
658                 switch (client->mode) {
659                 case MOUSEDEV_EMUL_PS2:
660                         client->ps2[1] = 0;
661                         break;
662                 case MOUSEDEV_EMUL_IMPS:
663                         client->ps2[1] = 3;
664                         break;
665                 case MOUSEDEV_EMUL_EXPS:
666                         client->ps2[1] = 4;
667                         break;
668                 }
669                 client->bufsiz = 2;
670                 break;
671
672         case 0xe9: /* Get info */
673                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
674                 client->bufsiz = 4;
675                 break;
676
677         case 0xff: /* Reset */
678                 client->impsseq = client->imexseq = 0;
679                 client->mode = MOUSEDEV_EMUL_PS2;
680                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
681                 client->bufsiz = 3;
682                 break;
683
684         default:
685                 client->bufsiz = 1;
686                 break;
687         }
688         client->buffer = client->bufsiz;
689 }
690
691 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
692                                 size_t count, loff_t *ppos)
693 {
694         struct mousedev_client *client = file->private_data;
695         unsigned char c;
696         unsigned int i;
697
698         for (i = 0; i < count; i++) {
699
700                 if (get_user(c, buffer + i))
701                         return -EFAULT;
702
703                 spin_lock_irq(&client->packet_lock);
704
705                 if (c == mousedev_imex_seq[client->imexseq]) {
706                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
707                                 client->imexseq = 0;
708                                 client->mode = MOUSEDEV_EMUL_EXPS;
709                         }
710                 } else
711                         client->imexseq = 0;
712
713                 if (c == mousedev_imps_seq[client->impsseq]) {
714                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
715                                 client->impsseq = 0;
716                                 client->mode = MOUSEDEV_EMUL_IMPS;
717                         }
718                 } else
719                         client->impsseq = 0;
720
721                 mousedev_generate_response(client, c);
722
723                 spin_unlock_irq(&client->packet_lock);
724         }
725
726         kill_fasync(&client->fasync, SIGIO, POLL_IN);
727         wake_up_interruptible(&client->mousedev->wait);
728
729         return count;
730 }
731
732 static ssize_t mousedev_read(struct file *file, char __user *buffer,
733                              size_t count, loff_t *ppos)
734 {
735         struct mousedev_client *client = file->private_data;
736         struct mousedev *mousedev = client->mousedev;
737         signed char data[sizeof(client->ps2)];
738         int retval = 0;
739
740         if (!client->ready && !client->buffer && mousedev->exist &&
741             (file->f_flags & O_NONBLOCK))
742                 return -EAGAIN;
743
744         retval = wait_event_interruptible(mousedev->wait,
745                         !mousedev->exist || client->ready || client->buffer);
746         if (retval)
747                 return retval;
748
749         if (!mousedev->exist)
750                 return -ENODEV;
751
752         spin_lock_irq(&client->packet_lock);
753
754         if (!client->buffer && client->ready) {
755                 mousedev_packet(client, client->ps2);
756                 client->buffer = client->bufsiz;
757         }
758
759         if (count > client->buffer)
760                 count = client->buffer;
761
762         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
763         client->buffer -= count;
764
765         spin_unlock_irq(&client->packet_lock);
766
767         if (copy_to_user(buffer, data, count))
768                 return -EFAULT;
769
770         return count;
771 }
772
773 /* No kernel lock - fine */
774 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
775 {
776         struct mousedev_client *client = file->private_data;
777         struct mousedev *mousedev = client->mousedev;
778
779         poll_wait(file, &mousedev->wait, wait);
780         return ((client->ready || client->buffer) ? (POLLIN | POLLRDNORM) : 0) |
781                 (mousedev->exist ? 0 : (POLLHUP | POLLERR));
782 }
783
784 static const struct file_operations mousedev_fops = {
785         .owner =        THIS_MODULE,
786         .read =         mousedev_read,
787         .write =        mousedev_write,
788         .poll =         mousedev_poll,
789         .open =         mousedev_open,
790         .release =      mousedev_release,
791         .fasync =       mousedev_fasync,
792 };
793
794 static int mousedev_install_chrdev(struct mousedev *mousedev)
795 {
796         mousedev_table[mousedev->minor] = mousedev;
797         return 0;
798 }
799
800 static void mousedev_remove_chrdev(struct mousedev *mousedev)
801 {
802         mutex_lock(&mousedev_table_mutex);
803         mousedev_table[mousedev->minor] = NULL;
804         mutex_unlock(&mousedev_table_mutex);
805 }
806
807 /*
808  * Mark device non-existent. This disables writes, ioctls and
809  * prevents new users from opening the device. Already posted
810  * blocking reads will stay, however new ones will fail.
811  */
812 static void mousedev_mark_dead(struct mousedev *mousedev)
813 {
814         mutex_lock(&mousedev->mutex);
815         mousedev->exist = 0;
816         mutex_unlock(&mousedev->mutex);
817 }
818
819 /*
820  * Wake up users waiting for IO so they can disconnect from
821  * dead device.
822  */
823 static void mousedev_hangup(struct mousedev *mousedev)
824 {
825         struct mousedev_client *client;
826
827         spin_lock(&mousedev->client_lock);
828         list_for_each_entry(client, &mousedev->client_list, node)
829                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
830         spin_unlock(&mousedev->client_lock);
831
832         wake_up_interruptible(&mousedev->wait);
833 }
834
835 static void mousedev_cleanup(struct mousedev *mousedev)
836 {
837         struct input_handle *handle = &mousedev->handle;
838
839         mousedev_mark_dead(mousedev);
840         mousedev_hangup(mousedev);
841         mousedev_remove_chrdev(mousedev);
842
843         /* mousedev is marked dead so no one else accesses mousedev->open */
844         if (mousedev->open)
845                 input_close_device(handle);
846 }
847
848 static struct mousedev *mousedev_create(struct input_dev *dev,
849                                         struct input_handler *handler,
850                                         int minor)
851 {
852         struct mousedev *mousedev;
853         int error;
854
855         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
856         if (!mousedev) {
857                 error = -ENOMEM;
858                 goto err_out;
859         }
860
861         INIT_LIST_HEAD(&mousedev->client_list);
862         INIT_LIST_HEAD(&mousedev->mixdev_node);
863         spin_lock_init(&mousedev->client_lock);
864         mutex_init(&mousedev->mutex);
865         lockdep_set_subclass(&mousedev->mutex,
866                              minor == MOUSEDEV_MIX ? MOUSEDEV_MIX : 0);
867         init_waitqueue_head(&mousedev->wait);
868
869         if (minor == MOUSEDEV_MIX)
870                 strlcpy(mousedev->name, "mice", sizeof(mousedev->name));
871         else
872                 snprintf(mousedev->name, sizeof(mousedev->name),
873                          "mouse%d", minor);
874
875         mousedev->minor = minor;
876         mousedev->exist = 1;
877         mousedev->handle.dev = input_get_device(dev);
878         mousedev->handle.name = mousedev->name;
879         mousedev->handle.handler = handler;
880         mousedev->handle.private = mousedev;
881
882         strlcpy(mousedev->dev.bus_id, mousedev->name,
883                 sizeof(mousedev->dev.bus_id));
884         mousedev->dev.class = &input_class;
885         if (dev)
886                 mousedev->dev.parent = &dev->dev;
887         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
888         mousedev->dev.release = mousedev_free;
889         device_initialize(&mousedev->dev);
890
891         if (minor != MOUSEDEV_MIX) {
892                 error = input_register_handle(&mousedev->handle);
893                 if (error)
894                         goto err_free_mousedev;
895         }
896
897         error = mousedev_install_chrdev(mousedev);
898         if (error)
899                 goto err_unregister_handle;
900
901         error = device_add(&mousedev->dev);
902         if (error)
903                 goto err_cleanup_mousedev;
904
905         return mousedev;
906
907  err_cleanup_mousedev:
908         mousedev_cleanup(mousedev);
909  err_unregister_handle:
910         if (minor != MOUSEDEV_MIX)
911                 input_unregister_handle(&mousedev->handle);
912  err_free_mousedev:
913         put_device(&mousedev->dev);
914  err_out:
915         return ERR_PTR(error);
916 }
917
918 static void mousedev_destroy(struct mousedev *mousedev)
919 {
920         device_del(&mousedev->dev);
921         mousedev_cleanup(mousedev);
922         if (mousedev->minor != MOUSEDEV_MIX)
923                 input_unregister_handle(&mousedev->handle);
924         put_device(&mousedev->dev);
925 }
926
927 static int mixdev_add_device(struct mousedev *mousedev)
928 {
929         int retval;
930
931         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
932         if (retval)
933                 return retval;
934
935         if (mousedev_mix->open) {
936                 retval = mousedev_open_device(mousedev);
937                 if (retval)
938                         goto out;
939
940                 mousedev->mixdev_open = 1;
941         }
942
943         get_device(&mousedev->dev);
944         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
945
946  out:
947         mutex_unlock(&mousedev_mix->mutex);
948         return retval;
949 }
950
951 static void mixdev_remove_device(struct mousedev *mousedev)
952 {
953         mutex_lock(&mousedev_mix->mutex);
954
955         if (mousedev->mixdev_open) {
956                 mousedev->mixdev_open = 0;
957                 mousedev_close_device(mousedev);
958         }
959
960         list_del_init(&mousedev->mixdev_node);
961         mutex_unlock(&mousedev_mix->mutex);
962
963         put_device(&mousedev->dev);
964 }
965
966 static int mousedev_connect(struct input_handler *handler,
967                             struct input_dev *dev,
968                             const struct input_device_id *id)
969 {
970         struct mousedev *mousedev;
971         int minor;
972         int error;
973
974         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
975                 if (!mousedev_table[minor])
976                         break;
977
978         if (minor == MOUSEDEV_MINORS) {
979                 printk(KERN_ERR "mousedev: no more free mousedev devices\n");
980                 return -ENFILE;
981         }
982
983         mousedev = mousedev_create(dev, handler, minor);
984         if (IS_ERR(mousedev))
985                 return PTR_ERR(mousedev);
986
987         error = mixdev_add_device(mousedev);
988         if (error) {
989                 mousedev_destroy(mousedev);
990                 return error;
991         }
992
993         return 0;
994 }
995
996 static void mousedev_disconnect(struct input_handle *handle)
997 {
998         struct mousedev *mousedev = handle->private;
999
1000         mixdev_remove_device(mousedev);
1001         mousedev_destroy(mousedev);
1002 }
1003
1004 static const struct input_device_id mousedev_ids[] = {
1005         {
1006                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1007                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1008                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1009                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1010                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1011                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1012         },      /* A mouse like device, at least one button,
1013                    two relative axes */
1014         {
1015                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1016                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1017                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1018                 .relbit = { BIT_MASK(REL_WHEEL) },
1019         },      /* A separate scrollwheel */
1020         {
1021                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1022                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1023                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1024                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1025                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1026                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1027         },      /* A tablet like device, at least touch detection,
1028                    two absolute axes */
1029         {
1030                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1031                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1032                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1033                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1034                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1035                                 BIT_MASK(BTN_TOOL_FINGER) },
1036                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1037                                 BIT_MASK(ABS_PRESSURE) |
1038                                 BIT_MASK(ABS_TOOL_WIDTH) },
1039         },      /* A touchpad */
1040         {
1041                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1042                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1043                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1044                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1045                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1046                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1047         },      /* Mouse-like device with absolute X and Y but ordinary
1048                    clicks, like hp ILO2 High Performance mouse */
1049
1050         { },    /* Terminating entry */
1051 };
1052
1053 MODULE_DEVICE_TABLE(input, mousedev_ids);
1054
1055 static struct input_handler mousedev_handler = {
1056         .event =        mousedev_event,
1057         .connect =      mousedev_connect,
1058         .disconnect =   mousedev_disconnect,
1059         .fops =         &mousedev_fops,
1060         .minor =        MOUSEDEV_MINOR_BASE,
1061         .name =         "mousedev",
1062         .id_table =     mousedev_ids,
1063 };
1064
1065 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1066 static struct miscdevice psaux_mouse = {
1067         PSMOUSE_MINOR, "psaux", &mousedev_fops
1068 };
1069 static int psaux_registered;
1070 #endif
1071
1072 static int __init mousedev_init(void)
1073 {
1074         int error;
1075
1076         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1077         if (IS_ERR(mousedev_mix))
1078                 return PTR_ERR(mousedev_mix);
1079
1080         error = input_register_handler(&mousedev_handler);
1081         if (error) {
1082                 mousedev_destroy(mousedev_mix);
1083                 return error;
1084         }
1085
1086 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1087         error = misc_register(&psaux_mouse);
1088         if (error)
1089                 printk(KERN_WARNING "mice: could not register psaux device, "
1090                         "error: %d\n", error);
1091         else
1092                 psaux_registered = 1;
1093 #endif
1094
1095         printk(KERN_INFO "mice: PS/2 mouse device common for all mice\n");
1096
1097         return 0;
1098 }
1099
1100 static void __exit mousedev_exit(void)
1101 {
1102 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1103         if (psaux_registered)
1104                 misc_deregister(&psaux_mouse);
1105 #endif
1106         input_unregister_handler(&mousedev_handler);
1107         mousedev_destroy(mousedev_mix);
1108 }
1109
1110 module_init(mousedev_init);
1111 module_exit(mousedev_exit);