Input: mousedev - use BIT_MASK instead of BIT
[linux-2.6] / 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         kfree(mousedev);
418 }
419
420 static int mousedev_open_device(struct mousedev *mousedev)
421 {
422         int retval;
423
424         retval = mutex_lock_interruptible(&mousedev->mutex);
425         if (retval)
426                 return retval;
427
428         if (mousedev->minor == MOUSEDEV_MIX)
429                 mixdev_open_devices();
430         else if (!mousedev->exist)
431                 retval = -ENODEV;
432         else if (!mousedev->open++) {
433                 retval = input_open_device(&mousedev->handle);
434                 if (retval)
435                         mousedev->open--;
436         }
437
438         mutex_unlock(&mousedev->mutex);
439         return retval;
440 }
441
442 static void mousedev_close_device(struct mousedev *mousedev)
443 {
444         mutex_lock(&mousedev->mutex);
445
446         if (mousedev->minor == MOUSEDEV_MIX)
447                 mixdev_close_devices();
448         else if (mousedev->exist && !--mousedev->open)
449                 input_close_device(&mousedev->handle);
450
451         mutex_unlock(&mousedev->mutex);
452 }
453
454 /*
455  * Open all available devices so they can all be multiplexed in one.
456  * stream. Note that this function is called with mousedev_mix->mutex
457  * held.
458  */
459 static void mixdev_open_devices(void)
460 {
461         struct mousedev *mousedev;
462
463         if (mousedev_mix->open++)
464                 return;
465
466         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
467                 if (!mousedev->mixdev_open) {
468                         if (mousedev_open_device(mousedev))
469                                 continue;
470
471                         mousedev->mixdev_open = 1;
472                 }
473         }
474 }
475
476 /*
477  * Close all devices that were opened as part of multiplexed
478  * device. Note that this function is called with mousedev_mix->mutex
479  * held.
480  */
481 static void mixdev_close_devices(void)
482 {
483         struct mousedev *mousedev;
484
485         if (--mousedev_mix->open)
486                 return;
487
488         list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
489                 if (mousedev->mixdev_open) {
490                         mousedev->mixdev_open = 0;
491                         mousedev_close_device(mousedev);
492                 }
493         }
494 }
495
496
497 static void mousedev_attach_client(struct mousedev *mousedev,
498                                    struct mousedev_client *client)
499 {
500         spin_lock(&mousedev->client_lock);
501         list_add_tail_rcu(&client->node, &mousedev->client_list);
502         spin_unlock(&mousedev->client_lock);
503         synchronize_rcu();
504 }
505
506 static void mousedev_detach_client(struct mousedev *mousedev,
507                                    struct mousedev_client *client)
508 {
509         spin_lock(&mousedev->client_lock);
510         list_del_rcu(&client->node);
511         spin_unlock(&mousedev->client_lock);
512         synchronize_rcu();
513 }
514
515 static int mousedev_release(struct inode *inode, struct file *file)
516 {
517         struct mousedev_client *client = file->private_data;
518         struct mousedev *mousedev = client->mousedev;
519
520         mousedev_fasync(-1, file, 0);
521         mousedev_detach_client(mousedev, client);
522         kfree(client);
523
524         mousedev_close_device(mousedev);
525         put_device(&mousedev->dev);
526
527         return 0;
528 }
529
530 static int mousedev_open(struct inode *inode, struct file *file)
531 {
532         struct mousedev_client *client;
533         struct mousedev *mousedev;
534         int error;
535         int i;
536
537 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
538         if (imajor(inode) == MISC_MAJOR)
539                 i = MOUSEDEV_MIX;
540         else
541 #endif
542                 i = iminor(inode) - MOUSEDEV_MINOR_BASE;
543
544         if (i >= MOUSEDEV_MINORS)
545                 return -ENODEV;
546
547         error = mutex_lock_interruptible(&mousedev_table_mutex);
548         if (error)
549                 return error;
550         mousedev = mousedev_table[i];
551         if (mousedev)
552                 get_device(&mousedev->dev);
553         mutex_unlock(&mousedev_table_mutex);
554
555         if (!mousedev)
556                 return -ENODEV;
557
558         client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
559         if (!client) {
560                 error = -ENOMEM;
561                 goto err_put_mousedev;
562         }
563
564         spin_lock_init(&client->packet_lock);
565         client->pos_x = xres / 2;
566         client->pos_y = yres / 2;
567         client->mousedev = mousedev;
568         mousedev_attach_client(mousedev, client);
569
570         error = mousedev_open_device(mousedev);
571         if (error)
572                 goto err_free_client;
573
574         file->private_data = client;
575         return 0;
576
577  err_free_client:
578         mousedev_detach_client(mousedev, client);
579         kfree(client);
580  err_put_mousedev:
581         put_device(&mousedev->dev);
582         return error;
583 }
584
585 static inline int mousedev_limit_delta(int delta, int limit)
586 {
587         return delta > limit ? limit : (delta < -limit ? -limit : delta);
588 }
589
590 static void mousedev_packet(struct mousedev_client *client,
591                             signed char *ps2_data)
592 {
593         struct mousedev_motion *p = &client->packets[client->tail];
594
595         ps2_data[0] = 0x08 |
596                 ((p->dx < 0) << 4) | ((p->dy < 0) << 5) | (p->buttons & 0x07);
597         ps2_data[1] = mousedev_limit_delta(p->dx, 127);
598         ps2_data[2] = mousedev_limit_delta(p->dy, 127);
599         p->dx -= ps2_data[1];
600         p->dy -= ps2_data[2];
601
602         switch (client->mode) {
603         case MOUSEDEV_EMUL_EXPS:
604                 ps2_data[3] = mousedev_limit_delta(p->dz, 7);
605                 p->dz -= ps2_data[3];
606                 ps2_data[3] = (ps2_data[3] & 0x0f) | ((p->buttons & 0x18) << 1);
607                 client->bufsiz = 4;
608                 break;
609
610         case MOUSEDEV_EMUL_IMPS:
611                 ps2_data[0] |=
612                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
613                 ps2_data[3] = mousedev_limit_delta(p->dz, 127);
614                 p->dz -= ps2_data[3];
615                 client->bufsiz = 4;
616                 break;
617
618         case MOUSEDEV_EMUL_PS2:
619         default:
620                 ps2_data[0] |=
621                         ((p->buttons & 0x10) >> 3) | ((p->buttons & 0x08) >> 1);
622                 p->dz = 0;
623                 client->bufsiz = 3;
624                 break;
625         }
626
627         if (!p->dx && !p->dy && !p->dz) {
628                 if (client->tail == client->head) {
629                         client->ready = 0;
630                         client->last_buttons = p->buttons;
631                 } else
632                         client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
633         }
634 }
635
636 static void mousedev_generate_response(struct mousedev_client *client,
637                                         int command)
638 {
639         client->ps2[0] = 0xfa; /* ACK */
640
641         switch (command) {
642
643         case 0xeb: /* Poll */
644                 mousedev_packet(client, &client->ps2[1]);
645                 client->bufsiz++; /* account for leading ACK */
646                 break;
647
648         case 0xf2: /* Get ID */
649                 switch (client->mode) {
650                 case MOUSEDEV_EMUL_PS2:
651                         client->ps2[1] = 0;
652                         break;
653                 case MOUSEDEV_EMUL_IMPS:
654                         client->ps2[1] = 3;
655                         break;
656                 case MOUSEDEV_EMUL_EXPS:
657                         client->ps2[1] = 4;
658                         break;
659                 }
660                 client->bufsiz = 2;
661                 break;
662
663         case 0xe9: /* Get info */
664                 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
665                 client->bufsiz = 4;
666                 break;
667
668         case 0xff: /* Reset */
669                 client->impsseq = client->imexseq = 0;
670                 client->mode = MOUSEDEV_EMUL_PS2;
671                 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
672                 client->bufsiz = 3;
673                 break;
674
675         default:
676                 client->bufsiz = 1;
677                 break;
678         }
679         client->buffer = client->bufsiz;
680 }
681
682 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
683                                 size_t count, loff_t *ppos)
684 {
685         struct mousedev_client *client = file->private_data;
686         unsigned char c;
687         unsigned int i;
688
689         for (i = 0; i < count; i++) {
690
691                 if (get_user(c, buffer + i))
692                         return -EFAULT;
693
694                 spin_lock_irq(&client->packet_lock);
695
696                 if (c == mousedev_imex_seq[client->imexseq]) {
697                         if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
698                                 client->imexseq = 0;
699                                 client->mode = MOUSEDEV_EMUL_EXPS;
700                         }
701                 } else
702                         client->imexseq = 0;
703
704                 if (c == mousedev_imps_seq[client->impsseq]) {
705                         if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
706                                 client->impsseq = 0;
707                                 client->mode = MOUSEDEV_EMUL_IMPS;
708                         }
709                 } else
710                         client->impsseq = 0;
711
712                 mousedev_generate_response(client, c);
713
714                 spin_unlock_irq(&client->packet_lock);
715         }
716
717         kill_fasync(&client->fasync, SIGIO, POLL_IN);
718         wake_up_interruptible(&client->mousedev->wait);
719
720         return count;
721 }
722
723 static ssize_t mousedev_read(struct file *file, char __user *buffer,
724                              size_t count, loff_t *ppos)
725 {
726         struct mousedev_client *client = file->private_data;
727         struct mousedev *mousedev = client->mousedev;
728         signed char data[sizeof(client->ps2)];
729         int retval = 0;
730
731         if (!client->ready && !client->buffer && mousedev->exist &&
732             (file->f_flags & O_NONBLOCK))
733                 return -EAGAIN;
734
735         retval = wait_event_interruptible(mousedev->wait,
736                         !mousedev->exist || client->ready || client->buffer);
737         if (retval)
738                 return retval;
739
740         if (!mousedev->exist)
741                 return -ENODEV;
742
743         spin_lock_irq(&client->packet_lock);
744
745         if (!client->buffer && client->ready) {
746                 mousedev_packet(client, client->ps2);
747                 client->buffer = client->bufsiz;
748         }
749
750         if (count > client->buffer)
751                 count = client->buffer;
752
753         memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
754         client->buffer -= count;
755
756         spin_unlock_irq(&client->packet_lock);
757
758         if (copy_to_user(buffer, data, count))
759                 return -EFAULT;
760
761         return count;
762 }
763
764 /* No kernel lock - fine */
765 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
766 {
767         struct mousedev_client *client = file->private_data;
768         struct mousedev *mousedev = client->mousedev;
769
770         poll_wait(file, &mousedev->wait, wait);
771         return ((client->ready || client->buffer) ? (POLLIN | POLLRDNORM) : 0) |
772                 (mousedev->exist ? 0 : (POLLHUP | POLLERR));
773 }
774
775 static const struct file_operations mousedev_fops = {
776         .owner =        THIS_MODULE,
777         .read =         mousedev_read,
778         .write =        mousedev_write,
779         .poll =         mousedev_poll,
780         .open =         mousedev_open,
781         .release =      mousedev_release,
782         .fasync =       mousedev_fasync,
783 };
784
785 static int mousedev_install_chrdev(struct mousedev *mousedev)
786 {
787         mousedev_table[mousedev->minor] = mousedev;
788         return 0;
789 }
790
791 static void mousedev_remove_chrdev(struct mousedev *mousedev)
792 {
793         mutex_lock(&mousedev_table_mutex);
794         mousedev_table[mousedev->minor] = NULL;
795         mutex_unlock(&mousedev_table_mutex);
796 }
797
798 /*
799  * Mark device non-existent. This disables writes, ioctls and
800  * prevents new users from opening the device. Already posted
801  * blocking reads will stay, however new ones will fail.
802  */
803 static void mousedev_mark_dead(struct mousedev *mousedev)
804 {
805         mutex_lock(&mousedev->mutex);
806         mousedev->exist = 0;
807         mutex_unlock(&mousedev->mutex);
808 }
809
810 /*
811  * Wake up users waiting for IO so they can disconnect from
812  * dead device.
813  */
814 static void mousedev_hangup(struct mousedev *mousedev)
815 {
816         struct mousedev_client *client;
817
818         spin_lock(&mousedev->client_lock);
819         list_for_each_entry(client, &mousedev->client_list, node)
820                 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
821         spin_unlock(&mousedev->client_lock);
822
823         wake_up_interruptible(&mousedev->wait);
824 }
825
826 static void mousedev_cleanup(struct mousedev *mousedev)
827 {
828         struct input_handle *handle = &mousedev->handle;
829
830         mousedev_mark_dead(mousedev);
831         mousedev_hangup(mousedev);
832         mousedev_remove_chrdev(mousedev);
833
834         /* mousedev is marked dead so no one else accesses mousedev->open */
835         if (mousedev->open)
836                 input_close_device(handle);
837 }
838
839 static struct mousedev *mousedev_create(struct input_dev *dev,
840                                         struct input_handler *handler,
841                                         int minor)
842 {
843         struct mousedev *mousedev;
844         int error;
845
846         mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
847         if (!mousedev) {
848                 error = -ENOMEM;
849                 goto err_out;
850         }
851
852         INIT_LIST_HEAD(&mousedev->client_list);
853         INIT_LIST_HEAD(&mousedev->mixdev_node);
854         spin_lock_init(&mousedev->client_lock);
855         mutex_init(&mousedev->mutex);
856         lockdep_set_subclass(&mousedev->mutex,
857                              minor == MOUSEDEV_MIX ? MOUSEDEV_MIX : 0);
858         init_waitqueue_head(&mousedev->wait);
859
860         if (minor == MOUSEDEV_MIX)
861                 strlcpy(mousedev->name, "mice", sizeof(mousedev->name));
862         else
863                 snprintf(mousedev->name, sizeof(mousedev->name),
864                          "mouse%d", minor);
865
866         mousedev->minor = minor;
867         mousedev->exist = 1;
868         mousedev->handle.dev = dev;
869         mousedev->handle.name = mousedev->name;
870         mousedev->handle.handler = handler;
871         mousedev->handle.private = mousedev;
872
873         strlcpy(mousedev->dev.bus_id, mousedev->name,
874                 sizeof(mousedev->dev.bus_id));
875         mousedev->dev.class = &input_class;
876         if (dev)
877                 mousedev->dev.parent = &dev->dev;
878         mousedev->dev.devt = MKDEV(INPUT_MAJOR, MOUSEDEV_MINOR_BASE + minor);
879         mousedev->dev.release = mousedev_free;
880         device_initialize(&mousedev->dev);
881
882         if (minor != MOUSEDEV_MIX) {
883                 error = input_register_handle(&mousedev->handle);
884                 if (error)
885                         goto err_free_mousedev;
886         }
887
888         error = mousedev_install_chrdev(mousedev);
889         if (error)
890                 goto err_unregister_handle;
891
892         error = device_add(&mousedev->dev);
893         if (error)
894                 goto err_cleanup_mousedev;
895
896         return mousedev;
897
898  err_cleanup_mousedev:
899         mousedev_cleanup(mousedev);
900  err_unregister_handle:
901         if (minor != MOUSEDEV_MIX)
902                 input_unregister_handle(&mousedev->handle);
903  err_free_mousedev:
904         put_device(&mousedev->dev);
905  err_out:
906         return ERR_PTR(error);
907 }
908
909 static void mousedev_destroy(struct mousedev *mousedev)
910 {
911         device_del(&mousedev->dev);
912         mousedev_cleanup(mousedev);
913         if (mousedev->minor != MOUSEDEV_MIX)
914                 input_unregister_handle(&mousedev->handle);
915         put_device(&mousedev->dev);
916 }
917
918 static int mixdev_add_device(struct mousedev *mousedev)
919 {
920         int retval;
921
922         retval = mutex_lock_interruptible(&mousedev_mix->mutex);
923         if (retval)
924                 return retval;
925
926         if (mousedev_mix->open) {
927                 retval = mousedev_open_device(mousedev);
928                 if (retval)
929                         goto out;
930
931                 mousedev->mixdev_open = 1;
932         }
933
934         get_device(&mousedev->dev);
935         list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
936
937  out:
938         mutex_unlock(&mousedev_mix->mutex);
939         return retval;
940 }
941
942 static void mixdev_remove_device(struct mousedev *mousedev)
943 {
944         mutex_lock(&mousedev_mix->mutex);
945
946         if (mousedev->mixdev_open) {
947                 mousedev->mixdev_open = 0;
948                 mousedev_close_device(mousedev);
949         }
950
951         list_del_init(&mousedev->mixdev_node);
952         mutex_unlock(&mousedev_mix->mutex);
953
954         put_device(&mousedev->dev);
955 }
956
957 static int mousedev_connect(struct input_handler *handler,
958                             struct input_dev *dev,
959                             const struct input_device_id *id)
960 {
961         struct mousedev *mousedev;
962         int minor;
963         int error;
964
965         for (minor = 0; minor < MOUSEDEV_MINORS; minor++)
966                 if (!mousedev_table[minor])
967                         break;
968
969         if (minor == MOUSEDEV_MINORS) {
970                 printk(KERN_ERR "mousedev: no more free mousedev devices\n");
971                 return -ENFILE;
972         }
973
974         mousedev = mousedev_create(dev, handler, minor);
975         if (IS_ERR(mousedev))
976                 return PTR_ERR(mousedev);
977
978         error = mixdev_add_device(mousedev);
979         if (error) {
980                 mousedev_destroy(mousedev);
981                 return error;
982         }
983
984         return 0;
985 }
986
987 static void mousedev_disconnect(struct input_handle *handle)
988 {
989         struct mousedev *mousedev = handle->private;
990
991         mixdev_remove_device(mousedev);
992         mousedev_destroy(mousedev);
993 }
994
995 static const struct input_device_id mousedev_ids[] = {
996         {
997                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
998                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
999                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1000                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1001                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1002                 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1003         },      /* A mouse like device, at least one button,
1004                    two relative axes */
1005         {
1006                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1007                                 INPUT_DEVICE_ID_MATCH_RELBIT,
1008                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1009                 .relbit = { BIT_MASK(REL_WHEEL) },
1010         },      /* A separate scrollwheel */
1011         {
1012                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1013                                 INPUT_DEVICE_ID_MATCH_KEYBIT |
1014                                 INPUT_DEVICE_ID_MATCH_ABSBIT,
1015                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1016                 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1017                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1018         },      /* A tablet like device, at least touch detection,
1019                    two absolute axes */
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_TOOL_FINGER)] =
1026                                 BIT_MASK(BTN_TOOL_FINGER) },
1027                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1028                                 BIT_MASK(ABS_PRESSURE) |
1029                                 BIT_MASK(ABS_TOOL_WIDTH) },
1030         },      /* A touchpad */
1031         {
1032                 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1033                         INPUT_DEVICE_ID_MATCH_KEYBIT |
1034                         INPUT_DEVICE_ID_MATCH_ABSBIT,
1035                 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1036                 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1037                 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1038         },      /* Mouse-like device with absolute X and Y but ordinary
1039                    clicks, like hp ILO2 High Performance mouse */
1040
1041         { },    /* Terminating entry */
1042 };
1043
1044 MODULE_DEVICE_TABLE(input, mousedev_ids);
1045
1046 static struct input_handler mousedev_handler = {
1047         .event =        mousedev_event,
1048         .connect =      mousedev_connect,
1049         .disconnect =   mousedev_disconnect,
1050         .fops =         &mousedev_fops,
1051         .minor =        MOUSEDEV_MINOR_BASE,
1052         .name =         "mousedev",
1053         .id_table =     mousedev_ids,
1054 };
1055
1056 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1057 static struct miscdevice psaux_mouse = {
1058         PSMOUSE_MINOR, "psaux", &mousedev_fops
1059 };
1060 static int psaux_registered;
1061 #endif
1062
1063 static int __init mousedev_init(void)
1064 {
1065         int error;
1066
1067         mousedev_mix = mousedev_create(NULL, &mousedev_handler, MOUSEDEV_MIX);
1068         if (IS_ERR(mousedev_mix))
1069                 return PTR_ERR(mousedev_mix);
1070
1071         error = input_register_handler(&mousedev_handler);
1072         if (error) {
1073                 mousedev_destroy(mousedev_mix);
1074                 return error;
1075         }
1076
1077 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1078         error = misc_register(&psaux_mouse);
1079         if (error)
1080                 printk(KERN_WARNING "mice: could not register psaux device, "
1081                         "error: %d\n", error);
1082         else
1083                 psaux_registered = 1;
1084 #endif
1085
1086         printk(KERN_INFO "mice: PS/2 mouse device common for all mice\n");
1087
1088         return 0;
1089 }
1090
1091 static void __exit mousedev_exit(void)
1092 {
1093 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1094         if (psaux_registered)
1095                 misc_deregister(&psaux_mouse);
1096 #endif
1097         input_unregister_handler(&mousedev_handler);
1098         mousedev_destroy(mousedev_mix);
1099 }
1100
1101 module_init(mousedev_init);
1102 module_exit(mousedev_exit);