b989748598ae2191cc58f806eb11a19290b847fe
[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/init.h>
20 #include <linux/input.h>
21 #include <linux/random.h>
22 #include <linux/major.h>
23 #include <linux/device.h>
24 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
25 #include <linux/miscdevice.h>
26 #endif
27
28 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
29 MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces");
30 MODULE_LICENSE("GPL");
31
32 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X
33 #define CONFIG_INPUT_MOUSEDEV_SCREEN_X  1024
34 #endif
35 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y
36 #define CONFIG_INPUT_MOUSEDEV_SCREEN_Y  768
37 #endif
38
39 static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
40 module_param(xres, uint, 0644);
41 MODULE_PARM_DESC(xres, "Horizontal screen resolution");
42
43 static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
44 module_param(yres, uint, 0644);
45 MODULE_PARM_DESC(yres, "Vertical screen resolution");
46
47 static unsigned tap_time = 200;
48 module_param(tap_time, uint, 0644);
49 MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)");
50
51 struct mousedev_hw_data {
52         int dx, dy, dz;
53         int x, y;
54         int abs_event;
55         unsigned long buttons;
56 };
57
58 struct mousedev {
59         int exist;
60         int open;
61         int minor;
62         char name[16];
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         int retval;
406         struct mousedev_client *client = file->private_data;
407
408         retval = fasync_helper(fd, file, on, &client->fasync);
409
410         return retval < 0 ? retval : 0;
411 }
412
413 static void mousedev_free(struct device *dev)
414 {
415         struct mousedev *mousedev = container_of(dev, struct mousedev, dev);
416
417         input_put_device(mousedev->handle.dev);
418         kfree(mousedev);
419 }
420
421 static int mousedev_open_device(struct mousedev *mousedev)
422 {
423         int retval;
424
425         retval = mutex_lock_interruptible(&mousedev->mutex);
426         if (retval)
427                 return retval;
428
429         if (mousedev->minor == MOUSEDEV_MIX)
430                 mixdev_open_devices();
431         else if (!mousedev->exist)
432                 retval = -ENODEV;
433         else if (!mousedev->open++) {
434                 retval = input_open_device(&mousedev->handle);
435                 if (retval)
436                         mousedev->open--;
437         }
438
439         mutex_unlock(&mousedev->mutex);
440         return retval;
441 }
442
443 static void mousedev_close_device(struct mousedev *mousedev)
444 {
445         mutex_lock(&mousedev->mutex);
446
447         if (mousedev->minor == MOUSEDEV_MIX)
448                 mixdev_close_devices();
449         else if (mousedev->exist && !--mousedev->open)
450                 input_close_device(&mousedev->handle);
451
452         mutex_unlock(&mousedev->mutex);
453 }
454
455 /*
456  * Open all available devices so they can all be multiplexed in one.
457  * stream. Note that this function is called with mousedev_mix->mutex
458  * held.
459  */
460 static void mixdev_open_devices(void)
461 {
462         struct mousedev *mousedev;
463
464         if (mousedev_mix->open++)
465                 return;
466
467         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
468                 if (!mousedev->mixdev_open) {
469                         if (mousedev_open_device(mousedev))
470                                 continue;
471
472                         mousedev->mixdev_open = 1;
473                 }
474         }
475 }
476
477 /*
478  * Close all devices that were opened as part of multiplexed
479  * device. Note that this function is called with mousedev_mix->mutex
480  * held.
481  */
482 static void mixdev_close_devices(void)
483 {
484         struct mousedev *mousedev;
485
486         if (--mousedev_mix->open)
487                 return;
488
489         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
490                 if (mousedev->mixdev_open) {
491                         mousedev->mixdev_open = 0;
492                         mousedev_close_device(mousedev);
493                 }
494         }
495 }
496
497
498 static void mousedev_attach_client(struct mousedev *mousedev,
499                                    struct mousedev_client *client)
500 {
501         spin_lock(&mousedev->client_lock);
502         list_add_tail_rcu(&client->node, &mousedev->client_list);
503         spin_unlock(&mousedev->client_lock);
504         synchronize_rcu();
505 }
506
507 static void mousedev_detach_client(struct mousedev *mousedev,
508                                    struct mousedev_client *client)
509 {
510         spin_lock(&mousedev->client_lock);
511         list_del_rcu(&client->node);
512         spin_unlock(&mousedev->client_lock);
513         synchronize_rcu();
514 }
515
516 static int mousedev_release(struct inode *inode, struct file *file)
517 {
518         struct mousedev_client *client = file->private_data;
519         struct mousedev *mousedev = client->mousedev;
520
521         mousedev_fasync(-1, file, 0);
522         mousedev_detach_client(mousedev, client);
523         kfree(client);
524
525         mousedev_close_device(mousedev);
526         put_device(&mousedev->dev);
527
528         return 0;
529 }
530
531 static int mousedev_open(struct inode *inode, struct file *file)
532 {
533         struct mousedev_client *client;
534         struct mousedev *mousedev;
535         int error;
536         int i;
537
538 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
539         if (imajor(inode) == MISC_MAJOR)
540                 i = MOUSEDEV_MIX;
541         else
542 #endif
543                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
544
545         if (i >= MOUSEDEV_MINORS)
546                 return -ENODEV;
547
548         error = mutex_lock_interruptible(&mousedev_table_mutex);
549         if (error)
550                 return error;
551         mousedev = mousedev_table[i];
552         if (mousedev)
553                 get_device(&mousedev->dev);
554         mutex_unlock(&mousedev_table_mutex);
555
556         if (!mousedev)
557                 return -ENODEV;
558
559         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
560         if (!client) {
561                 error = -ENOMEM;
562                 goto err_put_mousedev;
563         }
564
565         spin_lock_init(&client->packet_lock);
566         client->pos_x = xres / 2;
567         client->pos_y = yres / 2;
568         client->mousedev = mousedev;
569         mousedev_attach_client(mousedev, client);
570
571         error = mousedev_open_device(mousedev);
572         if (error)
573                 goto err_free_client;
574
575         file->private_data = client;
576         return 0;
577
578  err_free_client:
579         mousedev_detach_client(mousedev, client);
580         kfree(client);
581  err_put_mousedev:
582         put_device(&mousedev->dev);
583         return error;
584 }
585
586 static inline int mousedev_limit_delta(int delta, int limit)
587 {
588         return delta > limit ? limit : (delta < -limit ? -limit : delta);
589 }
590
591 static void mousedev_packet(struct mousedev_client *client,
592                             signed char *ps2_data)
593 {
594         struct mousedev_motion *p = &client->packets[client->tail];
595
596         ps2_data[0] = 0x08 |
597                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
598         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
599         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
600         p->dx -= ps2_data[1];
601         p->dy -= ps2_data[2];
602
603         switch (client->mode) {
604         case MOUSEDEV_EMUL_EXPS:
605                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
606                 p->dz -= ps2_data[3];
607                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
608                 client->bufsiz = 4;
609                 break;
610
611         case MOUSEDEV_EMUL_IMPS:
612                 ps2_data[0] |=
613                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
614                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
615                 p->dz -= ps2_data[3];
616                 client->bufsiz = 4;
617                 break;
618
619         case MOUSEDEV_EMUL_PS2:
620         default:
621                 ps2_data[0] |=
622                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
623                 p->dz = 0;
624                 client->bufsiz = 3;
625                 break;
626         }
627
628         if (!p->dx && !p->dy && !p->dz) {
629                 if (client->tail == client->head) {
630                         client->ready = 0;
631                         client->last_buttons = p->buttons;
632                 } else
633                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
634         }
635 }
636
637 static void mousedev_generate_response(struct mousedev_client *client,
638                                         int command)
639 {
640         client->ps2[0] = 0xfa; /* ACK */
641
642         switch (command) {
643
644         case 0xeb: /* Poll */
645                 mousedev_packet(client, &client->ps2[1]);
646                 client->bufsiz++; /* account for leading ACK */
647                 break;
648
649         case 0xf2: /* Get ID */
650                 switch (client->mode) {
651                 case MOUSEDEV_EMUL_PS2:
652                         client->ps2[1] = 0;
653                         break;
654                 case MOUSEDEV_EMUL_IMPS:
655                         client->ps2[1] = 3;
656                         break;
657                 case MOUSEDEV_EMUL_EXPS:
658                         client->ps2[1] = 4;
659                         break;
660                 }
661                 client->bufsiz = 2;
662                 break;
663
664         case 0xe9: /* Get info */
665                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
666                 client->bufsiz = 4;
667                 break;
668
669         case 0xff: /* Reset */
670                 client->impsseq = client->imexseq = 0;
671                 client->mode = MOUSEDEV_EMUL_PS2;
672                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
673                 client->bufsiz = 3;
674                 break;
675
676         default:
677                 client->bufsiz = 1;
678                 break;
679         }
680         client->buffer = client->bufsiz;
681 }
682
683 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
684                                 size_t count, loff_t *ppos)
685 {
686         struct mousedev_client *client = file->private_data;
687         unsigned char c;
688         unsigned int i;
689
690         for (i = 0; i < count; i++) {
691
692                 if (get_user(c, buffer + i))
693                         return -EFAULT;
694
695                 spin_lock_irq(&client->packet_lock);
696
697                 if (c == mousedev_imex_seq[client->imexseq]) {
698                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
699                                 client->imexseq = 0;
700                                 client->mode = MOUSEDEV_EMUL_EXPS;
701                         }
702                 } else
703                         client->imexseq = 0;
704
705                 if (c == mousedev_imps_seq[client->impsseq]) {
706                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
707                                 client->impsseq = 0;
708                                 client->mode = MOUSEDEV_EMUL_IMPS;
709                         }
710                 } else
711                         client->impsseq = 0;
712
713                 mousedev_generate_response(client, c);
714
715                 spin_unlock_irq(&client->packet_lock);
716         }
717
718         kill_fasync(&client->fasync, SIGIO, POLL_IN);
719         wake_up_interruptible(&client->mousedev->wait);
720
721         return count;
722 }
723
724 static ssize_t mousedev_read(struct file *file, char __user *buffer,
725                              size_t count, loff_t *ppos)
726 {
727         struct mousedev_client *client = file->private_data;
728         struct mousedev *mousedev = client->mousedev;
729         signed char data[sizeof(client->ps2)];
730         int retval = 0;
731
732         if (!client->ready && !client->buffer && mousedev->exist &&
733             (file->f_flags & O_NONBLOCK))
734                 return -EAGAIN;
735
736         retval = wait_event_interruptible(mousedev->wait,
737                         !mousedev->exist || client->ready || client->buffer);
738         if (retval)
739                 return retval;
740
741         if (!mousedev->exist)
742                 return -ENODEV;
743
744         spin_lock_irq(&client->packet_lock);
745
746         if (!client->buffer && client->ready) {
747                 mousedev_packet(client, client->ps2);
748                 client->buffer = client->bufsiz;
749         }
750
751         if (count > client->buffer)
752                 count = client->buffer;
753
754         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
755         client->buffer -= count;
756
757         spin_unlock_irq(&client->packet_lock);
758
759         if (copy_to_user(buffer, data, count))
760                 return -EFAULT;
761
762         return count;
763 }
764
765 /* No kernel lock - fine */
766 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
767 {
768         struct mousedev_client *client = file->private_data;
769         struct mousedev *mousedev = client->mousedev;
770
771         poll_wait(file, &mousedev->wait, wait);
772         return ((client->ready || client->buffer) ? (POLLIN | POLLRDNORM) : 0) |
773                 (mousedev->exist ? 0 : (POLLHUP | POLLERR));
774 }
775
776 static const struct file_operations mousedev_fops = {
777         .owner =        THIS_MODULE,
778         .read =         mousedev_read,
779         .write =        mousedev_write,
780         .poll =         mousedev_poll,
781         .open =         mousedev_open,
782         .release =      mousedev_release,
783         .fasync =       mousedev_fasync,
784 };
785
786 static int mousedev_install_chrdev(struct mousedev *mousedev)
787 {
788         mousedev_table[mousedev->minor] = mousedev;
789         return 0;
790 }
791
792 static void mousedev_remove_chrdev(struct mousedev *mousedev)
793 {
794         mutex_lock(&mousedev_table_mutex);
795         mousedev_table[mousedev->minor] = NULL;
796         mutex_unlock(&mousedev_table_mutex);
797 }
798
799 /*
800  * Mark device non-existent. This disables writes, ioctls and
801  * prevents new users from opening the device. Already posted
802  * blocking reads will stay, however new ones will fail.
803  */
804 static void mousedev_mark_dead(struct mousedev *mousedev)
805 {
806         mutex_lock(&mousedev->mutex);
807         mousedev->exist = 0;
808         mutex_unlock(&mousedev->mutex);
809 }
810
811 /*
812  * Wake up users waiting for IO so they can disconnect from
813  * dead device.
814  */
815 static void mousedev_hangup(struct mousedev *mousedev)
816 {
817         struct mousedev_client *client;
818
819         spin_lock(&mousedev->client_lock);
820         list_for_each_entry(client, &mousedev->client_list, node)
821                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
822         spin_unlock(&mousedev->client_lock);
823
824         wake_up_interruptible(&mousedev->wait);
825 }
826
827 static void mousedev_cleanup(struct mousedev *mousedev)
828 {
829         struct input_handle *handle = &mousedev->handle;
830
831         mousedev_mark_dead(mousedev);
832         mousedev_hangup(mousedev);
833         mousedev_remove_chrdev(mousedev);
834
835         /* mousedev is marked dead so no one else accesses mousedev->open */
836         if (mousedev->open)
837                 input_close_device(handle);
838 }
839
840 static struct mousedev *mousedev_create(struct input_dev *dev,
841                                         struct input_handler *handler,
842                                         int minor)
843 {
844         struct mousedev *mousedev;
845         int error;
846
847         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
848         if (!mousedev) {
849                 error = -ENOMEM;
850                 goto err_out;
851         }
852
853         INIT_LIST_HEAD(&mousedev->client_list);
854         INIT_LIST_HEAD(&mousedev->mixdev_node);
855         spin_lock_init(&mousedev->client_lock);
856         mutex_init(&mousedev->mutex);
857         lockdep_set_subclass(&mousedev->mutex,
858                              minor == MOUSEDEV_MIX ? MOUSEDEV_MIX : 0);
859         init_waitqueue_head(&mousedev->wait);
860
861         if (minor == MOUSEDEV_MIX)
862                 strlcpy(mousedev->name, "mice", sizeof(mousedev->name));
863         else
864                 snprintf(mousedev->name, sizeof(mousedev->name),
865                          "mouse%d", minor);
866
867         mousedev->minor = minor;
868         mousedev->exist = 1;
869         mousedev->handle.dev = input_get_device(dev);
870         mousedev->handle.name = mousedev->name;
871         mousedev->handle.handler = handler;
872         mousedev->handle.private = mousedev;
873
874         strlcpy(mousedev->dev.bus_id, mousedev->name,
875                 sizeof(mousedev->dev.bus_id));
876         mousedev->dev.class = &input_class;
877         if (dev)
878                 mousedev->dev.parent = &dev->dev;
879         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
880         mousedev->dev.release = mousedev_free;
881         device_initialize(&mousedev->dev);
882
883         if (minor != MOUSEDEV_MIX) {
884                 error = input_register_handle(&mousedev->handle);
885                 if (error)
886                         goto err_free_mousedev;
887         }
888
889         error = mousedev_install_chrdev(mousedev);
890         if (error)
891                 goto err_unregister_handle;
892
893         error = device_add(&mousedev->dev);
894         if (error)
895                 goto err_cleanup_mousedev;
896
897         return mousedev;
898
899  err_cleanup_mousedev:
900         mousedev_cleanup(mousedev);
901  err_unregister_handle:
902         if (minor != MOUSEDEV_MIX)
903                 input_unregister_handle(&mousedev->handle);
904  err_free_mousedev:
905         put_device(&mousedev->dev);
906  err_out:
907         return ERR_PTR(error);
908 }
909
910 static void mousedev_destroy(struct mousedev *mousedev)
911 {
912         device_del(&mousedev->dev);
913         mousedev_cleanup(mousedev);
914         if (mousedev->minor != MOUSEDEV_MIX)
915                 input_unregister_handle(&mousedev->handle);
916         put_device(&mousedev->dev);
917 }
918
919 static int mixdev_add_device(struct mousedev *mousedev)
920 {
921         int retval;
922
923         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
924         if (retval)
925                 return retval;
926
927         if (mousedev_mix->open) {
928                 retval = mousedev_open_device(mousedev);
929                 if (retval)
930                         goto out;
931
932                 mousedev->mixdev_open = 1;
933         }
934
935         get_device(&mousedev->dev);
936         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
937
938  out:
939         mutex_unlock(&mousedev_mix->mutex);
940         return retval;
941 }
942
943 static void mixdev_remove_device(struct mousedev *mousedev)
944 {
945         mutex_lock(&mousedev_mix->mutex);
946
947         if (mousedev->mixdev_open) {
948                 mousedev->mixdev_open = 0;
949                 mousedev_close_device(mousedev);
950         }
951
952         list_del_init(&mousedev->mixdev_node);
953         mutex_unlock(&mousedev_mix->mutex);
954
955         put_device(&mousedev->dev);
956 }
957
958 static int mousedev_connect(struct input_handler *handler,
959                             struct input_dev *dev,
960                             const struct input_device_id *id)
961 {
962         struct mousedev *mousedev;
963         int minor;
964         int error;
965
966         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
967                 if (!mousedev_table[minor])
968                         break;
969
970         if (minor == MOUSEDEV_MINORS) {
971                 printk(KERN_ERR "mousedev: no more free mousedev devices\n");
972                 return -ENFILE;
973         }
974
975         mousedev = mousedev_create(dev, handler, minor);
976         if (IS_ERR(mousedev))
977                 return PTR_ERR(mousedev);
978
979         error = mixdev_add_device(mousedev);
980         if (error) {
981                 mousedev_destroy(mousedev);
982                 return error;
983         }
984
985         return 0;
986 }
987
988 static void mousedev_disconnect(struct input_handle *handle)
989 {
990         struct mousedev *mousedev = handle->private;
991
992         mixdev_remove_device(mousedev);
993         mousedev_destroy(mousedev);
994 }
995
996 static const struct input_device_id mousedev_ids[] = {
997         {
998                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
999                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1000                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1001                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1002                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1003                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1004         },      /* A mouse like device, at least one button,
1005                    two relative axes */
1006         {
1007                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1008                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1009                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1010                 .relbit = { BIT_MASK(REL_WHEEL) },
1011         },      /* A separate scrollwheel */
1012         {
1013                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1014                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1015                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1016                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1017                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1018                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1019         },      /* A tablet like device, at least touch detection,
1020                    two absolute axes */
1021         {
1022                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1023                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1024                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1025                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1026                 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1027                                 BIT_MASK(BTN_TOOL_FINGER) },
1028                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1029                                 BIT_MASK(ABS_PRESSURE) |
1030                                 BIT_MASK(ABS_TOOL_WIDTH) },
1031         },      /* A touchpad */
1032         {
1033                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1034                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1035                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1036                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1037                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1038                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1039         },      /* Mouse-like device with absolute X and Y but ordinary
1040                    clicks, like hp ILO2 High Performance mouse */
1041
1042         { },    /* Terminating entry */
1043 };
1044
1045 MODULE_DEVICE_TABLE(input, mousedev_ids);
1046
1047 static struct input_handler mousedev_handler = {
1048         .event =        mousedev_event,
1049         .connect =      mousedev_connect,
1050         .disconnect =   mousedev_disconnect,
1051         .fops =         &mousedev_fops,
1052         .minor =        MOUSEDEV_MINOR_BASE,
1053         .name =         "mousedev",
1054         .id_table =     mousedev_ids,
1055 };
1056
1057 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1058 static struct miscdevice psaux_mouse = {
1059         PSMOUSE_MINOR, "psaux", &mousedev_fops
1060 };
1061 static int psaux_registered;
1062 #endif
1063
1064 static int __init mousedev_init(void)
1065 {
1066         int error;
1067
1068         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1069         if (IS_ERR(mousedev_mix))
1070                 return PTR_ERR(mousedev_mix);
1071
1072         error = input_register_handler(&mousedev_handler);
1073         if (error) {
1074                 mousedev_destroy(mousedev_mix);
1075                 return error;
1076         }
1077
1078 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1079         error = misc_register(&psaux_mouse);
1080         if (error)
1081                 printk(KERN_WARNING "mice: could not register psaux device, "
1082                         "error: %d\n", error);
1083         else
1084                 psaux_registered = 1;
1085 #endif
1086
1087         printk(KERN_INFO "mice: PS/2 mouse device common for all mice\n");
1088
1089         return 0;
1090 }
1091
1092 static void __exit mousedev_exit(void)
1093 {
1094 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1095         if (psaux_registered)
1096                 misc_deregister(&psaux_mouse);
1097 #endif
1098         input_unregister_handler(&mousedev_handler);
1099         mousedev_destroy(mousedev_mix);
1100 }
1101
1102 module_init(mousedev_init);
1103 module_exit(mousedev_exit);