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 pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14 #define MOUSEDEV_MINOR_BASE 32
15 #define MOUSEDEV_MINORS 31
16 #define MOUSEDEV_MIX 63
17
18 #include <linux/bitops.h>
19 #include <linux/sched.h>
20 #include <linux/slab.h>
21 #include <linux/poll.h>
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/input.h>
25 #include <linux/random.h>
26 #include <linux/major.h>
27 #include <linux/device.h>
28 #include <linux/cdev.h>
29 #include <linux/kernel.h>
30
31 MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
32 MODULE_DESCRIPTION("Mouse (ExplorerPS/2) device interfaces");
33 MODULE_LICENSE("GPL");
34
35 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_X
36 #define CONFIG_INPUT_MOUSEDEV_SCREEN_X 1024
37 #endif
38 #ifndef CONFIG_INPUT_MOUSEDEV_SCREEN_Y
39 #define CONFIG_INPUT_MOUSEDEV_SCREEN_Y 768
40 #endif
41
42 static int xres = CONFIG_INPUT_MOUSEDEV_SCREEN_X;
43 module_param(xres, uint, 0644);
44 MODULE_PARM_DESC(xres, "Horizontal screen resolution");
45
46 static int yres = CONFIG_INPUT_MOUSEDEV_SCREEN_Y;
47 module_param(yres, uint, 0644);
48 MODULE_PARM_DESC(yres, "Vertical screen resolution");
49
50 static unsigned tap_time = 200;
51 module_param(tap_time, uint, 0644);
52 MODULE_PARM_DESC(tap_time, "Tap time for touchpads in absolute mode (msecs)");
53
54 struct mousedev_hw_data {
55 int dx, dy, dz;
56 int x, y;
57 int abs_event;
58 unsigned long buttons;
59 };
60
61 struct mousedev {
62 int open;
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 struct cdev cdev;
70 bool exist;
71
72 struct list_head mixdev_node;
73 bool opened_by_mixdev;
74
75 struct mousedev_hw_data packet;
76 unsigned int pkt_count;
77 int old_x[4], old_y[4];
78 int frac_dx, frac_dy;
79 unsigned long touch;
80
81 int (*open_device)(struct mousedev *mousedev);
82 void (*close_device)(struct mousedev *mousedev);
83 };
84
85 enum mousedev_emul {
86 MOUSEDEV_EMUL_PS2,
87 MOUSEDEV_EMUL_IMPS,
88 MOUSEDEV_EMUL_EXPS
89 };
90
91 struct mousedev_motion {
92 int dx, dy, dz;
93 unsigned long buttons;
94 };
95
96 #define PACKET_QUEUE_LEN 16
97 struct mousedev_client {
98 struct fasync_struct *fasync;
99 struct mousedev *mousedev;
100 struct list_head node;
101
102 struct mousedev_motion packets[PACKET_QUEUE_LEN];
103 unsigned int head, tail;
104 spinlock_t packet_lock;
105 int pos_x, pos_y;
106
107 u8 ps2[6];
108 unsigned char ready, buffer, bufsiz;
109 unsigned char imexseq, impsseq;
110 enum mousedev_emul mode;
111 unsigned long last_buttons;
112 };
113
114 #define MOUSEDEV_SEQ_LEN 6
115
116 static unsigned char mousedev_imps_seq[] = { 0xf3, 200, 0xf3, 100, 0xf3, 80 };
117 static unsigned char mousedev_imex_seq[] = { 0xf3, 200, 0xf3, 200, 0xf3, 80 };
118
119 static struct mousedev *mousedev_mix;
120 static LIST_HEAD(mousedev_mix_list);
121
122 #define fx(i) (mousedev->old_x[(mousedev->pkt_count - (i)) & 03])
123 #define fy(i) (mousedev->old_y[(mousedev->pkt_count - (i)) & 03])
124
mousedev_touchpad_event(struct input_dev * dev,struct mousedev * mousedev,unsigned int code,int value)125 static void mousedev_touchpad_event(struct input_dev *dev,
126 struct mousedev *mousedev,
127 unsigned int code, int value)
128 {
129 int size, tmp;
130 enum { FRACTION_DENOM = 128 };
131
132 switch (code) {
133
134 case ABS_X:
135
136 fx(0) = value;
137 if (mousedev->touch && mousedev->pkt_count >= 2) {
138 size = input_abs_get_max(dev, ABS_X) -
139 input_abs_get_min(dev, ABS_X);
140 if (size == 0)
141 size = 256 * 2;
142
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 for ABS_Y to keep the same scale */
155 size = input_abs_get_max(dev, ABS_X) -
156 input_abs_get_min(dev, ABS_X);
157 if (size == 0)
158 size = 256 * 2;
159
160 tmp = -((value - fy(2)) * 256 * FRACTION_DENOM) / size;
161 tmp += mousedev->frac_dy;
162 mousedev->packet.dy = tmp / FRACTION_DENOM;
163 mousedev->frac_dy = tmp -
164 mousedev->packet.dy * FRACTION_DENOM;
165 }
166 break;
167 }
168 }
169
mousedev_abs_event(struct input_dev * dev,struct mousedev * mousedev,unsigned int code,int value)170 static void mousedev_abs_event(struct input_dev *dev, struct mousedev *mousedev,
171 unsigned int code, int value)
172 {
173 int min, max, size;
174
175 switch (code) {
176
177 case ABS_X:
178 min = input_abs_get_min(dev, ABS_X);
179 max = input_abs_get_max(dev, ABS_X);
180
181 size = max - min;
182 if (size == 0)
183 size = xres ? : 1;
184
185 value = clamp(value, min, max);
186
187 mousedev->packet.x = ((value - min) * xres) / size;
188 mousedev->packet.abs_event = 1;
189 break;
190
191 case ABS_Y:
192 min = input_abs_get_min(dev, ABS_Y);
193 max = input_abs_get_max(dev, ABS_Y);
194
195 size = max - min;
196 if (size == 0)
197 size = yres ? : 1;
198
199 value = clamp(value, min, max);
200
201 mousedev->packet.y = yres - ((value - min) * yres) / size;
202 mousedev->packet.abs_event = 1;
203 break;
204 }
205 }
206
mousedev_rel_event(struct mousedev * mousedev,unsigned int code,int value)207 static void mousedev_rel_event(struct mousedev *mousedev,
208 unsigned int code, int value)
209 {
210 switch (code) {
211 case REL_X:
212 mousedev->packet.dx += value;
213 break;
214
215 case REL_Y:
216 mousedev->packet.dy -= value;
217 break;
218
219 case REL_WHEEL:
220 mousedev->packet.dz -= value;
221 break;
222 }
223 }
224
mousedev_key_event(struct mousedev * mousedev,unsigned int code,int value)225 static void mousedev_key_event(struct mousedev *mousedev,
226 unsigned int code, int value)
227 {
228 int index;
229
230 switch (code) {
231
232 case BTN_TOUCH:
233 case BTN_0:
234 case BTN_LEFT: index = 0; break;
235
236 case BTN_STYLUS:
237 case BTN_1:
238 case BTN_RIGHT: index = 1; break;
239
240 case BTN_2:
241 case BTN_FORWARD:
242 case BTN_STYLUS2:
243 case BTN_MIDDLE: index = 2; break;
244
245 case BTN_3:
246 case BTN_BACK:
247 case BTN_SIDE: index = 3; break;
248
249 case BTN_4:
250 case BTN_EXTRA: index = 4; break;
251
252 default: return;
253 }
254
255 if (value) {
256 set_bit(index, &mousedev->packet.buttons);
257 set_bit(index, &mousedev_mix->packet.buttons);
258 } else {
259 clear_bit(index, &mousedev->packet.buttons);
260 clear_bit(index, &mousedev_mix->packet.buttons);
261 }
262 }
263
mousedev_notify_readers(struct mousedev * mousedev,struct mousedev_hw_data * packet)264 static void mousedev_notify_readers(struct mousedev *mousedev,
265 struct mousedev_hw_data *packet)
266 {
267 struct mousedev_client *client;
268 struct mousedev_motion *p;
269 unsigned int new_head;
270 int wake_readers = 0;
271
272 rcu_read_lock();
273 list_for_each_entry_rcu(client, &mousedev->client_list, node) {
274
275 /* Just acquire the lock, interrupts already disabled */
276 spin_lock(&client->packet_lock);
277
278 p = &client->packets[client->head];
279 if (client->ready && p->buttons != mousedev->packet.buttons) {
280 new_head = (client->head + 1) % PACKET_QUEUE_LEN;
281 if (new_head != client->tail) {
282 p = &client->packets[client->head = new_head];
283 memset(p, 0, sizeof(struct mousedev_motion));
284 }
285 }
286
287 if (packet->abs_event) {
288 p->dx += packet->x - client->pos_x;
289 p->dy += packet->y - client->pos_y;
290 client->pos_x = packet->x;
291 client->pos_y = packet->y;
292 }
293
294 client->pos_x += packet->dx;
295 client->pos_x = clamp_val(client->pos_x, 0, xres);
296
297 client->pos_y += packet->dy;
298 client->pos_y = clamp_val(client->pos_y, 0, yres);
299
300 p->dx += packet->dx;
301 p->dy += packet->dy;
302 p->dz += packet->dz;
303 p->buttons = mousedev->packet.buttons;
304
305 if (p->dx || p->dy || p->dz ||
306 p->buttons != client->last_buttons)
307 client->ready = 1;
308
309 spin_unlock(&client->packet_lock);
310
311 if (client->ready) {
312 kill_fasync(&client->fasync, SIGIO, POLL_IN);
313 wake_readers = 1;
314 }
315 }
316 rcu_read_unlock();
317
318 if (wake_readers)
319 wake_up_interruptible(&mousedev->wait);
320 }
321
mousedev_touchpad_touch(struct mousedev * mousedev,int value)322 static void mousedev_touchpad_touch(struct mousedev *mousedev, int value)
323 {
324 if (!value) {
325 if (mousedev->touch &&
326 time_before(jiffies,
327 mousedev->touch + msecs_to_jiffies(tap_time))) {
328 /*
329 * Toggle left button to emulate tap.
330 * We rely on the fact that mousedev_mix always has 0
331 * motion packet so we won't mess current position.
332 */
333 set_bit(0, &mousedev->packet.buttons);
334 set_bit(0, &mousedev_mix->packet.buttons);
335 mousedev_notify_readers(mousedev, &mousedev_mix->packet);
336 mousedev_notify_readers(mousedev_mix,
337 &mousedev_mix->packet);
338 clear_bit(0, &mousedev->packet.buttons);
339 clear_bit(0, &mousedev_mix->packet.buttons);
340 }
341 mousedev->touch = mousedev->pkt_count = 0;
342 mousedev->frac_dx = 0;
343 mousedev->frac_dy = 0;
344
345 } else if (!mousedev->touch)
346 mousedev->touch = jiffies;
347 }
348
mousedev_event(struct input_handle * handle,unsigned int type,unsigned int code,int value)349 static void mousedev_event(struct input_handle *handle,
350 unsigned int type, unsigned int code, int value)
351 {
352 struct mousedev *mousedev = handle->private;
353
354 switch (type) {
355
356 case EV_ABS:
357 /* Ignore joysticks */
358 if (test_bit(BTN_TRIGGER, handle->dev->keybit))
359 return;
360
361 if (test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
362 mousedev_touchpad_event(handle->dev,
363 mousedev, code, value);
364 else
365 mousedev_abs_event(handle->dev, mousedev, code, value);
366
367 break;
368
369 case EV_REL:
370 mousedev_rel_event(mousedev, code, value);
371 break;
372
373 case EV_KEY:
374 if (value != 2) {
375 if (code == BTN_TOUCH &&
376 test_bit(BTN_TOOL_FINGER, handle->dev->keybit))
377 mousedev_touchpad_touch(mousedev, value);
378 else
379 mousedev_key_event(mousedev, code, value);
380 }
381 break;
382
383 case EV_SYN:
384 if (code == SYN_REPORT) {
385 if (mousedev->touch) {
386 mousedev->pkt_count++;
387 /*
388 * Input system eats duplicate events,
389 * but we need all of them to do correct
390 * averaging so apply present one forward
391 */
392 fx(0) = fx(1);
393 fy(0) = fy(1);
394 }
395
396 mousedev_notify_readers(mousedev, &mousedev->packet);
397 mousedev_notify_readers(mousedev_mix, &mousedev->packet);
398
399 mousedev->packet.dx = mousedev->packet.dy =
400 mousedev->packet.dz = 0;
401 mousedev->packet.abs_event = 0;
402 }
403 break;
404 }
405 }
406
mousedev_fasync(int fd,struct file * file,int on)407 static int mousedev_fasync(int fd, struct file *file, int on)
408 {
409 struct mousedev_client *client = file->private_data;
410
411 return fasync_helper(fd, file, on, &client->fasync);
412 }
413
mousedev_free(struct device * dev)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
mousedev_open_device(struct mousedev * mousedev)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->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
mousedev_close_device(struct mousedev * mousedev)442 static void mousedev_close_device(struct mousedev *mousedev)
443 {
444 mutex_lock(&mousedev->mutex);
445
446 if (mousedev->exist && !--mousedev->open)
447 input_close_device(&mousedev->handle);
448
449 mutex_unlock(&mousedev->mutex);
450 }
451
452 /*
453 * Open all available devices so they can all be multiplexed in one.
454 * stream. Note that this function is called with mousedev_mix->mutex
455 * held.
456 */
mixdev_open_devices(struct mousedev * mixdev)457 static int mixdev_open_devices(struct mousedev *mixdev)
458 {
459 int error;
460
461 error = mutex_lock_interruptible(&mixdev->mutex);
462 if (error)
463 return error;
464
465 if (!mixdev->open++) {
466 struct mousedev *mousedev;
467
468 list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
469 if (!mousedev->opened_by_mixdev) {
470 if (mousedev_open_device(mousedev))
471 continue;
472
473 mousedev->opened_by_mixdev = true;
474 }
475 }
476 }
477
478 mutex_unlock(&mixdev->mutex);
479 return 0;
480 }
481
482 /*
483 * Close all devices that were opened as part of multiplexed
484 * device. Note that this function is called with mousedev_mix->mutex
485 * held.
486 */
mixdev_close_devices(struct mousedev * mixdev)487 static void mixdev_close_devices(struct mousedev *mixdev)
488 {
489 mutex_lock(&mixdev->mutex);
490
491 if (!--mixdev->open) {
492 struct mousedev *mousedev;
493
494 list_for_each_entry(mousedev, &mousedev_mix_list, mixdev_node) {
495 if (mousedev->opened_by_mixdev) {
496 mousedev->opened_by_mixdev = false;
497 mousedev_close_device(mousedev);
498 }
499 }
500 }
501
502 mutex_unlock(&mixdev->mutex);
503 }
504
505
mousedev_attach_client(struct mousedev * mousedev,struct mousedev_client * client)506 static void mousedev_attach_client(struct mousedev *mousedev,
507 struct mousedev_client *client)
508 {
509 spin_lock(&mousedev->client_lock);
510 list_add_tail_rcu(&client->node, &mousedev->client_list);
511 spin_unlock(&mousedev->client_lock);
512 }
513
mousedev_detach_client(struct mousedev * mousedev,struct mousedev_client * client)514 static void mousedev_detach_client(struct mousedev *mousedev,
515 struct mousedev_client *client)
516 {
517 spin_lock(&mousedev->client_lock);
518 list_del_rcu(&client->node);
519 spin_unlock(&mousedev->client_lock);
520 synchronize_rcu();
521 }
522
mousedev_release(struct inode * inode,struct file * file)523 static int mousedev_release(struct inode *inode, struct file *file)
524 {
525 struct mousedev_client *client = file->private_data;
526 struct mousedev *mousedev = client->mousedev;
527
528 mousedev_detach_client(mousedev, client);
529 kfree(client);
530
531 mousedev->close_device(mousedev);
532
533 return 0;
534 }
535
mousedev_open(struct inode * inode,struct file * file)536 static int mousedev_open(struct inode *inode, struct file *file)
537 {
538 struct mousedev_client *client;
539 struct mousedev *mousedev;
540 int error;
541
542 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
543 if (imajor(inode) == MISC_MAJOR)
544 mousedev = mousedev_mix;
545 else
546 #endif
547 mousedev = container_of(inode->i_cdev, struct mousedev, cdev);
548
549 client = kzalloc(sizeof(struct mousedev_client), GFP_KERNEL);
550 if (!client)
551 return -ENOMEM;
552
553 spin_lock_init(&client->packet_lock);
554 client->pos_x = xres / 2;
555 client->pos_y = yres / 2;
556 client->mousedev = mousedev;
557 mousedev_attach_client(mousedev, client);
558
559 error = mousedev->open_device(mousedev);
560 if (error)
561 goto err_free_client;
562
563 file->private_data = client;
564 nonseekable_open(inode, file);
565
566 return 0;
567
568 err_free_client:
569 mousedev_detach_client(mousedev, client);
570 kfree(client);
571 return error;
572 }
573
mousedev_packet(struct mousedev_client * client,u8 * ps2_data)574 static void mousedev_packet(struct mousedev_client *client, u8 *ps2_data)
575 {
576 struct mousedev_motion *p = &client->packets[client->tail];
577 s8 dx, dy, dz;
578
579 dx = clamp_val(p->dx, -127, 127);
580 p->dx -= dx;
581
582 dy = clamp_val(p->dy, -127, 127);
583 p->dy -= dy;
584
585 ps2_data[0] = BIT(3);
586 ps2_data[0] |= ((dx & BIT(7)) >> 3) | ((dy & BIT(7)) >> 2);
587 ps2_data[0] |= p->buttons & 0x07;
588 ps2_data[1] = dx;
589 ps2_data[2] = dy;
590
591 switch (client->mode) {
592 case MOUSEDEV_EMUL_EXPS:
593 dz = clamp_val(p->dz, -7, 7);
594 p->dz -= dz;
595
596 ps2_data[3] = (dz & 0x0f) | ((p->buttons & 0x18) << 1);
597 client->bufsiz = 4;
598 break;
599
600 case MOUSEDEV_EMUL_IMPS:
601 dz = clamp_val(p->dz, -127, 127);
602 p->dz -= dz;
603
604 ps2_data[0] |= ((p->buttons & 0x10) >> 3) |
605 ((p->buttons & 0x08) >> 1);
606 ps2_data[3] = dz;
607
608 client->bufsiz = 4;
609 break;
610
611 case MOUSEDEV_EMUL_PS2:
612 default:
613 p->dz = 0;
614
615 ps2_data[0] |= ((p->buttons & 0x10) >> 3) |
616 ((p->buttons & 0x08) >> 1);
617
618 client->bufsiz = 3;
619 break;
620 }
621
622 if (!p->dx && !p->dy && !p->dz) {
623 if (client->tail == client->head) {
624 client->ready = 0;
625 client->last_buttons = p->buttons;
626 } else
627 client->tail = (client->tail + 1) % PACKET_QUEUE_LEN;
628 }
629 }
630
mousedev_generate_response(struct mousedev_client * client,int command)631 static void mousedev_generate_response(struct mousedev_client *client,
632 int command)
633 {
634 client->ps2[0] = 0xfa; /* ACK */
635
636 switch (command) {
637
638 case 0xeb: /* Poll */
639 mousedev_packet(client, &client->ps2[1]);
640 client->bufsiz++; /* account for leading ACK */
641 break;
642
643 case 0xf2: /* Get ID */
644 switch (client->mode) {
645 case MOUSEDEV_EMUL_PS2:
646 client->ps2[1] = 0;
647 break;
648 case MOUSEDEV_EMUL_IMPS:
649 client->ps2[1] = 3;
650 break;
651 case MOUSEDEV_EMUL_EXPS:
652 client->ps2[1] = 4;
653 break;
654 }
655 client->bufsiz = 2;
656 break;
657
658 case 0xe9: /* Get info */
659 client->ps2[1] = 0x60; client->ps2[2] = 3; client->ps2[3] = 200;
660 client->bufsiz = 4;
661 break;
662
663 case 0xff: /* Reset */
664 client->impsseq = client->imexseq = 0;
665 client->mode = MOUSEDEV_EMUL_PS2;
666 client->ps2[1] = 0xaa; client->ps2[2] = 0x00;
667 client->bufsiz = 3;
668 break;
669
670 default:
671 client->bufsiz = 1;
672 break;
673 }
674 client->buffer = client->bufsiz;
675 }
676
mousedev_write(struct file * file,const char __user * buffer,size_t count,loff_t * ppos)677 static ssize_t mousedev_write(struct file *file, const char __user *buffer,
678 size_t count, loff_t *ppos)
679 {
680 struct mousedev_client *client = file->private_data;
681 unsigned char c;
682 unsigned int i;
683
684 for (i = 0; i < count; i++) {
685
686 if (get_user(c, buffer + i))
687 return -EFAULT;
688
689 spin_lock_irq(&client->packet_lock);
690
691 if (c == mousedev_imex_seq[client->imexseq]) {
692 if (++client->imexseq == MOUSEDEV_SEQ_LEN) {
693 client->imexseq = 0;
694 client->mode = MOUSEDEV_EMUL_EXPS;
695 }
696 } else
697 client->imexseq = 0;
698
699 if (c == mousedev_imps_seq[client->impsseq]) {
700 if (++client->impsseq == MOUSEDEV_SEQ_LEN) {
701 client->impsseq = 0;
702 client->mode = MOUSEDEV_EMUL_IMPS;
703 }
704 } else
705 client->impsseq = 0;
706
707 mousedev_generate_response(client, c);
708
709 spin_unlock_irq(&client->packet_lock);
710 }
711
712 kill_fasync(&client->fasync, SIGIO, POLL_IN);
713 wake_up_interruptible(&client->mousedev->wait);
714
715 return count;
716 }
717
mousedev_read(struct file * file,char __user * buffer,size_t count,loff_t * ppos)718 static ssize_t mousedev_read(struct file *file, char __user *buffer,
719 size_t count, loff_t *ppos)
720 {
721 struct mousedev_client *client = file->private_data;
722 struct mousedev *mousedev = client->mousedev;
723 u8 data[sizeof(client->ps2)];
724 int retval = 0;
725
726 if (!client->ready && !client->buffer && mousedev->exist &&
727 (file->f_flags & O_NONBLOCK))
728 return -EAGAIN;
729
730 retval = wait_event_interruptible(mousedev->wait,
731 !mousedev->exist || client->ready || client->buffer);
732 if (retval)
733 return retval;
734
735 if (!mousedev->exist)
736 return -ENODEV;
737
738 spin_lock_irq(&client->packet_lock);
739
740 if (!client->buffer && client->ready) {
741 mousedev_packet(client, client->ps2);
742 client->buffer = client->bufsiz;
743 }
744
745 if (count > client->buffer)
746 count = client->buffer;
747
748 memcpy(data, client->ps2 + client->bufsiz - client->buffer, count);
749 client->buffer -= count;
750
751 spin_unlock_irq(&client->packet_lock);
752
753 if (copy_to_user(buffer, data, count))
754 return -EFAULT;
755
756 return count;
757 }
758
759 /* No kernel lock - fine */
mousedev_poll(struct file * file,poll_table * wait)760 static unsigned int mousedev_poll(struct file *file, poll_table *wait)
761 {
762 struct mousedev_client *client = file->private_data;
763 struct mousedev *mousedev = client->mousedev;
764 unsigned int mask;
765
766 poll_wait(file, &mousedev->wait, wait);
767
768 mask = mousedev->exist ? POLLOUT | POLLWRNORM : POLLHUP | POLLERR;
769 if (client->ready || client->buffer)
770 mask |= POLLIN | POLLRDNORM;
771
772 return mask;
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 .llseek = noop_llseek,
784 };
785
786 /*
787 * Mark device non-existent. This disables writes, ioctls and
788 * prevents new users from opening the device. Already posted
789 * blocking reads will stay, however new ones will fail.
790 */
mousedev_mark_dead(struct mousedev * mousedev)791 static void mousedev_mark_dead(struct mousedev *mousedev)
792 {
793 mutex_lock(&mousedev->mutex);
794 mousedev->exist = false;
795 mutex_unlock(&mousedev->mutex);
796 }
797
798 /*
799 * Wake up users waiting for IO so they can disconnect from
800 * dead device.
801 */
mousedev_hangup(struct mousedev * mousedev)802 static void mousedev_hangup(struct mousedev *mousedev)
803 {
804 struct mousedev_client *client;
805
806 spin_lock(&mousedev->client_lock);
807 list_for_each_entry(client, &mousedev->client_list, node)
808 kill_fasync(&client->fasync, SIGIO, POLL_HUP);
809 spin_unlock(&mousedev->client_lock);
810
811 wake_up_interruptible(&mousedev->wait);
812 }
813
mousedev_cleanup(struct mousedev * mousedev)814 static void mousedev_cleanup(struct mousedev *mousedev)
815 {
816 struct input_handle *handle = &mousedev->handle;
817
818 mousedev_mark_dead(mousedev);
819 mousedev_hangup(mousedev);
820
821 cdev_del(&mousedev->cdev);
822
823 /* mousedev is marked dead so no one else accesses mousedev->open */
824 if (mousedev->open)
825 input_close_device(handle);
826 }
827
mousedev_reserve_minor(bool mixdev)828 static int mousedev_reserve_minor(bool mixdev)
829 {
830 int minor;
831
832 if (mixdev) {
833 minor = input_get_new_minor(MOUSEDEV_MIX, 1, false);
834 if (minor < 0)
835 pr_err("failed to reserve mixdev minor: %d\n", minor);
836 } else {
837 minor = input_get_new_minor(MOUSEDEV_MINOR_BASE,
838 MOUSEDEV_MINORS, true);
839 if (minor < 0)
840 pr_err("failed to reserve new minor: %d\n", minor);
841 }
842
843 return minor;
844 }
845
mousedev_create(struct input_dev * dev,struct input_handler * handler,bool mixdev)846 static struct mousedev *mousedev_create(struct input_dev *dev,
847 struct input_handler *handler,
848 bool mixdev)
849 {
850 struct mousedev *mousedev;
851 int minor;
852 int error;
853
854 minor = mousedev_reserve_minor(mixdev);
855 if (minor < 0) {
856 error = minor;
857 goto err_out;
858 }
859
860 mousedev = kzalloc(sizeof(struct mousedev), GFP_KERNEL);
861 if (!mousedev) {
862 error = -ENOMEM;
863 goto err_free_minor;
864 }
865
866 INIT_LIST_HEAD(&mousedev->client_list);
867 INIT_LIST_HEAD(&mousedev->mixdev_node);
868 spin_lock_init(&mousedev->client_lock);
869 mutex_init(&mousedev->mutex);
870 lockdep_set_subclass(&mousedev->mutex,
871 mixdev ? SINGLE_DEPTH_NESTING : 0);
872 init_waitqueue_head(&mousedev->wait);
873
874 if (mixdev) {
875 dev_set_name(&mousedev->dev, "mice");
876
877 mousedev->open_device = mixdev_open_devices;
878 mousedev->close_device = mixdev_close_devices;
879 } else {
880 int dev_no = minor;
881 /* Normalize device number if it falls into legacy range */
882 if (dev_no < MOUSEDEV_MINOR_BASE + MOUSEDEV_MINORS)
883 dev_no -= MOUSEDEV_MINOR_BASE;
884 dev_set_name(&mousedev->dev, "mouse%d", dev_no);
885
886 mousedev->open_device = mousedev_open_device;
887 mousedev->close_device = mousedev_close_device;
888 }
889
890 mousedev->exist = true;
891 mousedev->handle.dev = input_get_device(dev);
892 mousedev->handle.name = dev_name(&mousedev->dev);
893 mousedev->handle.handler = handler;
894 mousedev->handle.private = mousedev;
895
896 mousedev->dev.class = &input_class;
897 if (dev)
898 mousedev->dev.parent = &dev->dev;
899 mousedev->dev.devt = MKDEV(INPUT_MAJOR, minor);
900 mousedev->dev.release = mousedev_free;
901 device_initialize(&mousedev->dev);
902
903 if (!mixdev) {
904 error = input_register_handle(&mousedev->handle);
905 if (error)
906 goto err_free_mousedev;
907 }
908
909 cdev_init(&mousedev->cdev, &mousedev_fops);
910 mousedev->cdev.kobj.parent = &mousedev->dev.kobj;
911 error = cdev_add(&mousedev->cdev, mousedev->dev.devt, 1);
912 if (error)
913 goto err_unregister_handle;
914
915 error = device_add(&mousedev->dev);
916 if (error)
917 goto err_cleanup_mousedev;
918
919 return mousedev;
920
921 err_cleanup_mousedev:
922 mousedev_cleanup(mousedev);
923 err_unregister_handle:
924 if (!mixdev)
925 input_unregister_handle(&mousedev->handle);
926 err_free_mousedev:
927 put_device(&mousedev->dev);
928 err_free_minor:
929 input_free_minor(minor);
930 err_out:
931 return ERR_PTR(error);
932 }
933
mousedev_destroy(struct mousedev * mousedev)934 static void mousedev_destroy(struct mousedev *mousedev)
935 {
936 device_del(&mousedev->dev);
937 mousedev_cleanup(mousedev);
938 input_free_minor(MINOR(mousedev->dev.devt));
939 if (mousedev != mousedev_mix)
940 input_unregister_handle(&mousedev->handle);
941 put_device(&mousedev->dev);
942 }
943
mixdev_add_device(struct mousedev * mousedev)944 static int mixdev_add_device(struct mousedev *mousedev)
945 {
946 int retval;
947
948 retval = mutex_lock_interruptible(&mousedev_mix->mutex);
949 if (retval)
950 return retval;
951
952 if (mousedev_mix->open) {
953 retval = mousedev_open_device(mousedev);
954 if (retval)
955 goto out;
956
957 mousedev->opened_by_mixdev = true;
958 }
959
960 get_device(&mousedev->dev);
961 list_add_tail(&mousedev->mixdev_node, &mousedev_mix_list);
962
963 out:
964 mutex_unlock(&mousedev_mix->mutex);
965 return retval;
966 }
967
mixdev_remove_device(struct mousedev * mousedev)968 static void mixdev_remove_device(struct mousedev *mousedev)
969 {
970 mutex_lock(&mousedev_mix->mutex);
971
972 if (mousedev->opened_by_mixdev) {
973 mousedev->opened_by_mixdev = false;
974 mousedev_close_device(mousedev);
975 }
976
977 list_del_init(&mousedev->mixdev_node);
978 mutex_unlock(&mousedev_mix->mutex);
979
980 put_device(&mousedev->dev);
981 }
982
mousedev_connect(struct input_handler * handler,struct input_dev * dev,const struct input_device_id * id)983 static int mousedev_connect(struct input_handler *handler,
984 struct input_dev *dev,
985 const struct input_device_id *id)
986 {
987 struct mousedev *mousedev;
988 int error;
989
990 mousedev = mousedev_create(dev, handler, false);
991 if (IS_ERR(mousedev))
992 return PTR_ERR(mousedev);
993
994 error = mixdev_add_device(mousedev);
995 if (error) {
996 mousedev_destroy(mousedev);
997 return error;
998 }
999
1000 return 0;
1001 }
1002
mousedev_disconnect(struct input_handle * handle)1003 static void mousedev_disconnect(struct input_handle *handle)
1004 {
1005 struct mousedev *mousedev = handle->private;
1006
1007 mixdev_remove_device(mousedev);
1008 mousedev_destroy(mousedev);
1009 }
1010
1011 static const struct input_device_id mousedev_ids[] = {
1012 {
1013 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1014 INPUT_DEVICE_ID_MATCH_KEYBIT |
1015 INPUT_DEVICE_ID_MATCH_RELBIT,
1016 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1017 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1018 .relbit = { BIT_MASK(REL_X) | BIT_MASK(REL_Y) },
1019 }, /* A mouse like device, at least one button,
1020 two relative axes */
1021 {
1022 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1023 INPUT_DEVICE_ID_MATCH_RELBIT,
1024 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_REL) },
1025 .relbit = { BIT_MASK(REL_WHEEL) },
1026 }, /* A separate scrollwheel */
1027 {
1028 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1029 INPUT_DEVICE_ID_MATCH_KEYBIT |
1030 INPUT_DEVICE_ID_MATCH_ABSBIT,
1031 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1032 .keybit = { [BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
1033 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1034 }, /* A tablet like device, at least touch detection,
1035 two absolute axes */
1036 {
1037 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1038 INPUT_DEVICE_ID_MATCH_KEYBIT |
1039 INPUT_DEVICE_ID_MATCH_ABSBIT,
1040 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1041 .keybit = { [BIT_WORD(BTN_TOOL_FINGER)] =
1042 BIT_MASK(BTN_TOOL_FINGER) },
1043 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) |
1044 BIT_MASK(ABS_PRESSURE) |
1045 BIT_MASK(ABS_TOOL_WIDTH) },
1046 }, /* A touchpad */
1047 {
1048 .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
1049 INPUT_DEVICE_ID_MATCH_KEYBIT |
1050 INPUT_DEVICE_ID_MATCH_ABSBIT,
1051 .evbit = { BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) },
1052 .keybit = { [BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) },
1053 .absbit = { BIT_MASK(ABS_X) | BIT_MASK(ABS_Y) },
1054 }, /* Mouse-like device with absolute X and Y but ordinary
1055 clicks, like hp ILO2 High Performance mouse */
1056
1057 { }, /* Terminating entry */
1058 };
1059
1060 MODULE_DEVICE_TABLE(input, mousedev_ids);
1061
1062 static struct input_handler mousedev_handler = {
1063 .event = mousedev_event,
1064 .connect = mousedev_connect,
1065 .disconnect = mousedev_disconnect,
1066 .legacy_minors = true,
1067 .minor = MOUSEDEV_MINOR_BASE,
1068 .name = "mousedev",
1069 .id_table = mousedev_ids,
1070 };
1071
1072 #ifdef CONFIG_INPUT_MOUSEDEV_PSAUX
1073 #include <linux/miscdevice.h>
1074
1075 static struct miscdevice psaux_mouse = {
1076 .minor = PSMOUSE_MINOR,
1077 .name = "psaux",
1078 .fops = &mousedev_fops,
1079 };
1080
1081 static bool psaux_registered;
1082
mousedev_psaux_register(void)1083 static void __init mousedev_psaux_register(void)
1084 {
1085 int error;
1086
1087 error = misc_register(&psaux_mouse);
1088 if (error)
1089 pr_warn("could not register psaux device, error: %d\n",
1090 error);
1091 else
1092 psaux_registered = true;
1093 }
1094
mousedev_psaux_unregister(void)1095 static void __exit mousedev_psaux_unregister(void)
1096 {
1097 if (psaux_registered)
1098 misc_deregister(&psaux_mouse);
1099 }
1100 #else
mousedev_psaux_register(void)1101 static inline void mousedev_psaux_register(void) { }
mousedev_psaux_unregister(void)1102 static inline void mousedev_psaux_unregister(void) { }
1103 #endif
1104
mousedev_init(void)1105 static int __init mousedev_init(void)
1106 {
1107 int error;
1108
1109 mousedev_mix = mousedev_create(NULL, &mousedev_handler, true);
1110 if (IS_ERR(mousedev_mix))
1111 return PTR_ERR(mousedev_mix);
1112
1113 error = input_register_handler(&mousedev_handler);
1114 if (error) {
1115 mousedev_destroy(mousedev_mix);
1116 return error;
1117 }
1118
1119 mousedev_psaux_register();
1120
1121 pr_info("PS/2 mouse device common for all mice\n");
1122
1123 return 0;
1124 }
1125
mousedev_exit(void)1126 static void __exit mousedev_exit(void)
1127 {
1128 mousedev_psaux_unregister();
1129 input_unregister_handler(&mousedev_handler);
1130 mousedev_destroy(mousedev_mix);
1131 }
1132
1133 module_init(mousedev_init);
1134 module_exit(mousedev_exit);
1135