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1/*
2 * linux/drivers/char/ppdev.c
3 *
4 * This is the code behind /dev/parport* -- it allows a user-space
5 * application to use the parport subsystem.
6 *
7 * Copyright (C) 1998-2000, 2002 Tim Waugh <tim@cyberelk.net>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 *
14 * A /dev/parportx device node represents an arbitrary device
15 * on port 'x'. The following operations are possible:
16 *
17 * open do nothing, set up default IEEE 1284 protocol to be COMPAT
18 * close release port and unregister device (if necessary)
19 * ioctl
20 * EXCL register device exclusively (may fail)
21 * CLAIM (register device first time) parport_claim_or_block
22 * RELEASE parport_release
23 * SETMODE set the IEEE 1284 protocol to use for read/write
24 * SETPHASE set the IEEE 1284 phase of a particular mode. Not to be
25 * confused with ioctl(fd, SETPHASER, &stun). ;-)
26 * DATADIR data_forward / data_reverse
27 * WDATA write_data
28 * RDATA read_data
29 * WCONTROL write_control
30 * RCONTROL read_control
31 * FCONTROL frob_control
32 * RSTATUS read_status
33 * NEGOT parport_negotiate
34 * YIELD parport_yield_blocking
35 * WCTLONIRQ on interrupt, set control lines
36 * CLRIRQ clear (and return) interrupt count
37 * SETTIME sets device timeout (struct timeval)
38 * GETTIME gets device timeout (struct timeval)
39 * GETMODES gets hardware supported modes (unsigned int)
40 * GETMODE gets the current IEEE1284 mode
41 * GETPHASE gets the current IEEE1284 phase
42 * GETFLAGS gets current (user-visible) flags
43 * SETFLAGS sets current (user-visible) flags
44 * read/write read or write in current IEEE 1284 protocol
45 * select wait for interrupt (in readfds)
46 *
47 * Changes:
48 * Added SETTIME/GETTIME ioctl, Fred Barnes, 1999.
49 *
50 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 2000/08/25
51 * - On error, copy_from_user and copy_to_user do not return -EFAULT,
52 * They return the positive number of bytes *not* copied due to address
53 * space errors.
54 *
55 * Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <frmb2@ukc.ac.uk>, 03/01/2001.
56 * Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001
57 */
58
59#include <linux/module.h>
60#include <linux/init.h>
61#include <linux/sched.h>
62#include <linux/device.h>
63#include <linux/ioctl.h>
64#include <linux/parport.h>
65#include <linux/ctype.h>
66#include <linux/poll.h>
67#include <linux/slab.h>
68#include <linux/major.h>
69#include <linux/ppdev.h>
70#include <linux/mutex.h>
71#include <linux/uaccess.h>
72
73#define PP_VERSION "ppdev: user-space parallel port driver"
74#define CHRDEV "ppdev"
75
76struct pp_struct {
77 struct pardevice * pdev;
78 wait_queue_head_t irq_wait;
79 atomic_t irqc;
80 unsigned int flags;
81 int irqresponse;
82 unsigned char irqctl;
83 struct ieee1284_info state;
84 struct ieee1284_info saved_state;
85 long default_inactivity;
86};
87
88/* pp_struct.flags bitfields */
89#define PP_CLAIMED (1<<0)
90#define PP_EXCL (1<<1)
91
92/* Other constants */
93#define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */
94#define PP_BUFFER_SIZE 1024
95#define PARDEVICE_MAX 8
96
97/* ROUND_UP macro from fs/select.c */
98#define ROUND_UP(x,y) (((x)+(y)-1)/(y))
99
100static DEFINE_MUTEX(pp_do_mutex);
101static inline void pp_enable_irq (struct pp_struct *pp)
102{
103 struct parport *port = pp->pdev->port;
104 port->ops->enable_irq (port);
105}
106
107static ssize_t pp_read (struct file * file, char __user * buf, size_t count,
108 loff_t * ppos)
109{
110 unsigned int minor = iminor(file->f_path.dentry->d_inode);
111 struct pp_struct *pp = file->private_data;
112 char * kbuffer;
113 ssize_t bytes_read = 0;
114 struct parport *pport;
115 int mode;
116
117 if (!(pp->flags & PP_CLAIMED)) {
118 /* Don't have the port claimed */
119 pr_debug(CHRDEV "%x: claim the port first\n", minor);
120 return -EINVAL;
121 }
122
123 /* Trivial case. */
124 if (count == 0)
125 return 0;
126
127 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
128 if (!kbuffer) {
129 return -ENOMEM;
130 }
131 pport = pp->pdev->port;
132 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
133
134 parport_set_timeout (pp->pdev,
135 (file->f_flags & O_NONBLOCK) ?
136 PARPORT_INACTIVITY_O_NONBLOCK :
137 pp->default_inactivity);
138
139 while (bytes_read == 0) {
140 ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE);
141
142 if (mode == IEEE1284_MODE_EPP) {
143 /* various specials for EPP mode */
144 int flags = 0;
145 size_t (*fn)(struct parport *, void *, size_t, int);
146
147 if (pp->flags & PP_W91284PIC) {
148 flags |= PARPORT_W91284PIC;
149 }
150 if (pp->flags & PP_FASTREAD) {
151 flags |= PARPORT_EPP_FAST;
152 }
153 if (pport->ieee1284.mode & IEEE1284_ADDR) {
154 fn = pport->ops->epp_read_addr;
155 } else {
156 fn = pport->ops->epp_read_data;
157 }
158 bytes_read = (*fn)(pport, kbuffer, need, flags);
159 } else {
160 bytes_read = parport_read (pport, kbuffer, need);
161 }
162
163 if (bytes_read != 0)
164 break;
165
166 if (file->f_flags & O_NONBLOCK) {
167 bytes_read = -EAGAIN;
168 break;
169 }
170
171 if (signal_pending (current)) {
172 bytes_read = -ERESTARTSYS;
173 break;
174 }
175
176 cond_resched();
177 }
178
179 parport_set_timeout (pp->pdev, pp->default_inactivity);
180
181 if (bytes_read > 0 && copy_to_user (buf, kbuffer, bytes_read))
182 bytes_read = -EFAULT;
183
184 kfree (kbuffer);
185 pp_enable_irq (pp);
186 return bytes_read;
187}
188
189static ssize_t pp_write (struct file * file, const char __user * buf,
190 size_t count, loff_t * ppos)
191{
192 unsigned int minor = iminor(file->f_path.dentry->d_inode);
193 struct pp_struct *pp = file->private_data;
194 char * kbuffer;
195 ssize_t bytes_written = 0;
196 ssize_t wrote;
197 int mode;
198 struct parport *pport;
199
200 if (!(pp->flags & PP_CLAIMED)) {
201 /* Don't have the port claimed */
202 pr_debug(CHRDEV "%x: claim the port first\n", minor);
203 return -EINVAL;
204 }
205
206 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
207 if (!kbuffer) {
208 return -ENOMEM;
209 }
210 pport = pp->pdev->port;
211 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
212
213 parport_set_timeout (pp->pdev,
214 (file->f_flags & O_NONBLOCK) ?
215 PARPORT_INACTIVITY_O_NONBLOCK :
216 pp->default_inactivity);
217
218 while (bytes_written < count) {
219 ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE);
220
221 if (copy_from_user (kbuffer, buf + bytes_written, n)) {
222 bytes_written = -EFAULT;
223 break;
224 }
225
226 if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) {
227 /* do a fast EPP write */
228 if (pport->ieee1284.mode & IEEE1284_ADDR) {
229 wrote = pport->ops->epp_write_addr (pport,
230 kbuffer, n, PARPORT_EPP_FAST);
231 } else {
232 wrote = pport->ops->epp_write_data (pport,
233 kbuffer, n, PARPORT_EPP_FAST);
234 }
235 } else {
236 wrote = parport_write (pp->pdev->port, kbuffer, n);
237 }
238
239 if (wrote <= 0) {
240 if (!bytes_written) {
241 bytes_written = wrote;
242 }
243 break;
244 }
245
246 bytes_written += wrote;
247
248 if (file->f_flags & O_NONBLOCK) {
249 if (!bytes_written)
250 bytes_written = -EAGAIN;
251 break;
252 }
253
254 if (signal_pending (current)) {
255 if (!bytes_written) {
256 bytes_written = -EINTR;
257 }
258 break;
259 }
260
261 cond_resched();
262 }
263
264 parport_set_timeout (pp->pdev, pp->default_inactivity);
265
266 kfree (kbuffer);
267 pp_enable_irq (pp);
268 return bytes_written;
269}
270
271static void pp_irq (void *private)
272{
273 struct pp_struct *pp = private;
274
275 if (pp->irqresponse) {
276 parport_write_control (pp->pdev->port, pp->irqctl);
277 pp->irqresponse = 0;
278 }
279
280 atomic_inc (&pp->irqc);
281 wake_up_interruptible (&pp->irq_wait);
282}
283
284static int register_device (int minor, struct pp_struct *pp)
285{
286 struct parport *port;
287 struct pardevice * pdev = NULL;
288 char *name;
289 int fl;
290
291 name = kasprintf(GFP_KERNEL, CHRDEV "%x", minor);
292 if (name == NULL)
293 return -ENOMEM;
294
295 port = parport_find_number (minor);
296 if (!port) {
297 printk (KERN_WARNING "%s: no associated port!\n", name);
298 kfree (name);
299 return -ENXIO;
300 }
301
302 fl = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0;
303 pdev = parport_register_device (port, name, NULL,
304 NULL, pp_irq, fl, pp);
305 parport_put_port (port);
306
307 if (!pdev) {
308 printk (KERN_WARNING "%s: failed to register device!\n", name);
309 kfree (name);
310 return -ENXIO;
311 }
312
313 pp->pdev = pdev;
314 pr_debug("%s: registered pardevice\n", name);
315 return 0;
316}
317
318static enum ieee1284_phase init_phase (int mode)
319{
320 switch (mode & ~(IEEE1284_DEVICEID
321 | IEEE1284_ADDR)) {
322 case IEEE1284_MODE_NIBBLE:
323 case IEEE1284_MODE_BYTE:
324 return IEEE1284_PH_REV_IDLE;
325 }
326 return IEEE1284_PH_FWD_IDLE;
327}
328
329static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
330{
331 unsigned int minor = iminor(file->f_path.dentry->d_inode);
332 struct pp_struct *pp = file->private_data;
333 struct parport * port;
334 void __user *argp = (void __user *)arg;
335
336 /* First handle the cases that don't take arguments. */
337 switch (cmd) {
338 case PPCLAIM:
339 {
340 struct ieee1284_info *info;
341 int ret;
342
343 if (pp->flags & PP_CLAIMED) {
344 pr_debug(CHRDEV "%x: you've already got it!\n", minor);
345 return -EINVAL;
346 }
347
348 /* Deferred device registration. */
349 if (!pp->pdev) {
350 int err = register_device (minor, pp);
351 if (err) {
352 return err;
353 }
354 }
355
356 ret = parport_claim_or_block (pp->pdev);
357 if (ret < 0)
358 return ret;
359
360 pp->flags |= PP_CLAIMED;
361
362 /* For interrupt-reporting to work, we need to be
363 * informed of each interrupt. */
364 pp_enable_irq (pp);
365
366 /* We may need to fix up the state machine. */
367 info = &pp->pdev->port->ieee1284;
368 pp->saved_state.mode = info->mode;
369 pp->saved_state.phase = info->phase;
370 info->mode = pp->state.mode;
371 info->phase = pp->state.phase;
372 pp->default_inactivity = parport_set_timeout (pp->pdev, 0);
373 parport_set_timeout (pp->pdev, pp->default_inactivity);
374
375 return 0;
376 }
377 case PPEXCL:
378 if (pp->pdev) {
379 pr_debug(CHRDEV "%x: too late for PPEXCL; "
380 "already registered\n", minor);
381 if (pp->flags & PP_EXCL)
382 /* But it's not really an error. */
383 return 0;
384 /* There's no chance of making the driver happy. */
385 return -EINVAL;
386 }
387
388 /* Just remember to register the device exclusively
389 * when we finally do the registration. */
390 pp->flags |= PP_EXCL;
391 return 0;
392 case PPSETMODE:
393 {
394 int mode;
395 if (copy_from_user (&mode, argp, sizeof (mode)))
396 return -EFAULT;
397 /* FIXME: validate mode */
398 pp->state.mode = mode;
399 pp->state.phase = init_phase (mode);
400
401 if (pp->flags & PP_CLAIMED) {
402 pp->pdev->port->ieee1284.mode = mode;
403 pp->pdev->port->ieee1284.phase = pp->state.phase;
404 }
405
406 return 0;
407 }
408 case PPGETMODE:
409 {
410 int mode;
411
412 if (pp->flags & PP_CLAIMED) {
413 mode = pp->pdev->port->ieee1284.mode;
414 } else {
415 mode = pp->state.mode;
416 }
417 if (copy_to_user (argp, &mode, sizeof (mode))) {
418 return -EFAULT;
419 }
420 return 0;
421 }
422 case PPSETPHASE:
423 {
424 int phase;
425 if (copy_from_user (&phase, argp, sizeof (phase))) {
426 return -EFAULT;
427 }
428 /* FIXME: validate phase */
429 pp->state.phase = phase;
430
431 if (pp->flags & PP_CLAIMED) {
432 pp->pdev->port->ieee1284.phase = phase;
433 }
434
435 return 0;
436 }
437 case PPGETPHASE:
438 {
439 int phase;
440
441 if (pp->flags & PP_CLAIMED) {
442 phase = pp->pdev->port->ieee1284.phase;
443 } else {
444 phase = pp->state.phase;
445 }
446 if (copy_to_user (argp, &phase, sizeof (phase))) {
447 return -EFAULT;
448 }
449 return 0;
450 }
451 case PPGETMODES:
452 {
453 unsigned int modes;
454
455 port = parport_find_number (minor);
456 if (!port)
457 return -ENODEV;
458
459 modes = port->modes;
460 parport_put_port(port);
461 if (copy_to_user (argp, &modes, sizeof (modes))) {
462 return -EFAULT;
463 }
464 return 0;
465 }
466 case PPSETFLAGS:
467 {
468 int uflags;
469
470 if (copy_from_user (&uflags, argp, sizeof (uflags))) {
471 return -EFAULT;
472 }
473 pp->flags &= ~PP_FLAGMASK;
474 pp->flags |= (uflags & PP_FLAGMASK);
475 return 0;
476 }
477 case PPGETFLAGS:
478 {
479 int uflags;
480
481 uflags = pp->flags & PP_FLAGMASK;
482 if (copy_to_user (argp, &uflags, sizeof (uflags))) {
483 return -EFAULT;
484 }
485 return 0;
486 }
487 } /* end switch() */
488
489 /* Everything else requires the port to be claimed, so check
490 * that now. */
491 if ((pp->flags & PP_CLAIMED) == 0) {
492 pr_debug(CHRDEV "%x: claim the port first\n", minor);
493 return -EINVAL;
494 }
495
496 port = pp->pdev->port;
497 switch (cmd) {
498 struct ieee1284_info *info;
499 unsigned char reg;
500 unsigned char mask;
501 int mode;
502 int ret;
503 struct timeval par_timeout;
504 long to_jiffies;
505
506 case PPRSTATUS:
507 reg = parport_read_status (port);
508 if (copy_to_user (argp, ®, sizeof (reg)))
509 return -EFAULT;
510 return 0;
511 case PPRDATA:
512 reg = parport_read_data (port);
513 if (copy_to_user (argp, ®, sizeof (reg)))
514 return -EFAULT;
515 return 0;
516 case PPRCONTROL:
517 reg = parport_read_control (port);
518 if (copy_to_user (argp, ®, sizeof (reg)))
519 return -EFAULT;
520 return 0;
521 case PPYIELD:
522 parport_yield_blocking (pp->pdev);
523 return 0;
524
525 case PPRELEASE:
526 /* Save the state machine's state. */
527 info = &pp->pdev->port->ieee1284;
528 pp->state.mode = info->mode;
529 pp->state.phase = info->phase;
530 info->mode = pp->saved_state.mode;
531 info->phase = pp->saved_state.phase;
532 parport_release (pp->pdev);
533 pp->flags &= ~PP_CLAIMED;
534 return 0;
535
536 case PPWCONTROL:
537 if (copy_from_user (®, argp, sizeof (reg)))
538 return -EFAULT;
539 parport_write_control (port, reg);
540 return 0;
541
542 case PPWDATA:
543 if (copy_from_user (®, argp, sizeof (reg)))
544 return -EFAULT;
545 parport_write_data (port, reg);
546 return 0;
547
548 case PPFCONTROL:
549 if (copy_from_user (&mask, argp,
550 sizeof (mask)))
551 return -EFAULT;
552 if (copy_from_user (®, 1 + (unsigned char __user *) arg,
553 sizeof (reg)))
554 return -EFAULT;
555 parport_frob_control (port, mask, reg);
556 return 0;
557
558 case PPDATADIR:
559 if (copy_from_user (&mode, argp, sizeof (mode)))
560 return -EFAULT;
561 if (mode)
562 port->ops->data_reverse (port);
563 else
564 port->ops->data_forward (port);
565 return 0;
566
567 case PPNEGOT:
568 if (copy_from_user (&mode, argp, sizeof (mode)))
569 return -EFAULT;
570 switch ((ret = parport_negotiate (port, mode))) {
571 case 0: break;
572 case -1: /* handshake failed, peripheral not IEEE 1284 */
573 ret = -EIO;
574 break;
575 case 1: /* handshake succeeded, peripheral rejected mode */
576 ret = -ENXIO;
577 break;
578 }
579 pp_enable_irq (pp);
580 return ret;
581
582 case PPWCTLONIRQ:
583 if (copy_from_user (®, argp, sizeof (reg)))
584 return -EFAULT;
585
586 /* Remember what to set the control lines to, for next
587 * time we get an interrupt. */
588 pp->irqctl = reg;
589 pp->irqresponse = 1;
590 return 0;
591
592 case PPCLRIRQ:
593 ret = atomic_read (&pp->irqc);
594 if (copy_to_user (argp, &ret, sizeof (ret)))
595 return -EFAULT;
596 atomic_sub (ret, &pp->irqc);
597 return 0;
598
599 case PPSETTIME:
600 if (copy_from_user (&par_timeout, argp, sizeof(struct timeval))) {
601 return -EFAULT;
602 }
603 /* Convert to jiffies, place in pp->pdev->timeout */
604 if ((par_timeout.tv_sec < 0) || (par_timeout.tv_usec < 0)) {
605 return -EINVAL;
606 }
607 to_jiffies = ROUND_UP(par_timeout.tv_usec, 1000000/HZ);
608 to_jiffies += par_timeout.tv_sec * (long)HZ;
609 if (to_jiffies <= 0) {
610 return -EINVAL;
611 }
612 pp->pdev->timeout = to_jiffies;
613 return 0;
614
615 case PPGETTIME:
616 to_jiffies = pp->pdev->timeout;
617 memset(&par_timeout, 0, sizeof(par_timeout));
618 par_timeout.tv_sec = to_jiffies / HZ;
619 par_timeout.tv_usec = (to_jiffies % (long)HZ) * (1000000/HZ);
620 if (copy_to_user (argp, &par_timeout, sizeof(struct timeval)))
621 return -EFAULT;
622 return 0;
623
624 default:
625 pr_debug(CHRDEV "%x: What? (cmd=0x%x)\n", minor, cmd);
626 return -EINVAL;
627 }
628
629 /* Keep the compiler happy */
630 return 0;
631}
632
633static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
634{
635 long ret;
636 mutex_lock(&pp_do_mutex);
637 ret = pp_do_ioctl(file, cmd, arg);
638 mutex_unlock(&pp_do_mutex);
639 return ret;
640}
641
642static int pp_open (struct inode * inode, struct file * file)
643{
644 unsigned int minor = iminor(inode);
645 struct pp_struct *pp;
646
647 if (minor >= PARPORT_MAX)
648 return -ENXIO;
649
650 pp = kmalloc (sizeof (struct pp_struct), GFP_KERNEL);
651 if (!pp)
652 return -ENOMEM;
653
654 pp->state.mode = IEEE1284_MODE_COMPAT;
655 pp->state.phase = init_phase (pp->state.mode);
656 pp->flags = 0;
657 pp->irqresponse = 0;
658 atomic_set (&pp->irqc, 0);
659 init_waitqueue_head (&pp->irq_wait);
660
661 /* Defer the actual device registration until the first claim.
662 * That way, we know whether or not the driver wants to have
663 * exclusive access to the port (PPEXCL).
664 */
665 pp->pdev = NULL;
666 file->private_data = pp;
667
668 return 0;
669}
670
671static int pp_release (struct inode * inode, struct file * file)
672{
673 unsigned int minor = iminor(inode);
674 struct pp_struct *pp = file->private_data;
675 int compat_negot;
676
677 compat_negot = 0;
678 if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
679 (pp->state.mode != IEEE1284_MODE_COMPAT)) {
680 struct ieee1284_info *info;
681
682 /* parport released, but not in compatibility mode */
683 parport_claim_or_block (pp->pdev);
684 pp->flags |= PP_CLAIMED;
685 info = &pp->pdev->port->ieee1284;
686 pp->saved_state.mode = info->mode;
687 pp->saved_state.phase = info->phase;
688 info->mode = pp->state.mode;
689 info->phase = pp->state.phase;
690 compat_negot = 1;
691 } else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
692 (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
693 compat_negot = 2;
694 }
695 if (compat_negot) {
696 parport_negotiate (pp->pdev->port, IEEE1284_MODE_COMPAT);
697 pr_debug(CHRDEV "%x: negotiated back to compatibility "
698 "mode because user-space forgot\n", minor);
699 }
700
701 if (pp->flags & PP_CLAIMED) {
702 struct ieee1284_info *info;
703
704 info = &pp->pdev->port->ieee1284;
705 pp->state.mode = info->mode;
706 pp->state.phase = info->phase;
707 info->mode = pp->saved_state.mode;
708 info->phase = pp->saved_state.phase;
709 parport_release (pp->pdev);
710 if (compat_negot != 1) {
711 pr_debug(CHRDEV "%x: released pardevice "
712 "because user-space forgot\n", minor);
713 }
714 }
715
716 if (pp->pdev) {
717 const char *name = pp->pdev->name;
718 parport_unregister_device (pp->pdev);
719 kfree (name);
720 pp->pdev = NULL;
721 pr_debug(CHRDEV "%x: unregistered pardevice\n", minor);
722 }
723
724 kfree (pp);
725
726 return 0;
727}
728
729/* No kernel lock held - fine */
730static unsigned int pp_poll (struct file * file, poll_table * wait)
731{
732 struct pp_struct *pp = file->private_data;
733 unsigned int mask = 0;
734
735 poll_wait (file, &pp->irq_wait, wait);
736 if (atomic_read (&pp->irqc))
737 mask |= POLLIN | POLLRDNORM;
738
739 return mask;
740}
741
742static struct class *ppdev_class;
743
744static const struct file_operations pp_fops = {
745 .owner = THIS_MODULE,
746 .llseek = no_llseek,
747 .read = pp_read,
748 .write = pp_write,
749 .poll = pp_poll,
750 .unlocked_ioctl = pp_ioctl,
751 .open = pp_open,
752 .release = pp_release,
753};
754
755static void pp_attach(struct parport *port)
756{
757 device_create(ppdev_class, port->dev, MKDEV(PP_MAJOR, port->number),
758 NULL, "parport%d", port->number);
759}
760
761static void pp_detach(struct parport *port)
762{
763 device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number));
764}
765
766static struct parport_driver pp_driver = {
767 .name = CHRDEV,
768 .attach = pp_attach,
769 .detach = pp_detach,
770};
771
772static int __init ppdev_init (void)
773{
774 int err = 0;
775
776 if (register_chrdev (PP_MAJOR, CHRDEV, &pp_fops)) {
777 printk (KERN_WARNING CHRDEV ": unable to get major %d\n",
778 PP_MAJOR);
779 return -EIO;
780 }
781 ppdev_class = class_create(THIS_MODULE, CHRDEV);
782 if (IS_ERR(ppdev_class)) {
783 err = PTR_ERR(ppdev_class);
784 goto out_chrdev;
785 }
786 if (parport_register_driver(&pp_driver)) {
787 printk (KERN_WARNING CHRDEV ": unable to register with parport\n");
788 goto out_class;
789 }
790
791 printk (KERN_INFO PP_VERSION "\n");
792 goto out;
793
794out_class:
795 class_destroy(ppdev_class);
796out_chrdev:
797 unregister_chrdev(PP_MAJOR, CHRDEV);
798out:
799 return err;
800}
801
802static void __exit ppdev_cleanup (void)
803{
804 /* Clean up all parport stuff */
805 parport_unregister_driver(&pp_driver);
806 class_destroy(ppdev_class);
807 unregister_chrdev (PP_MAJOR, CHRDEV);
808}
809
810module_init(ppdev_init);
811module_exit(ppdev_cleanup);
812
813MODULE_LICENSE("GPL");
814MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);
1/*
2 * linux/drivers/char/ppdev.c
3 *
4 * This is the code behind /dev/parport* -- it allows a user-space
5 * application to use the parport subsystem.
6 *
7 * Copyright (C) 1998-2000, 2002 Tim Waugh <tim@cyberelk.net>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 *
14 * A /dev/parportx device node represents an arbitrary device
15 * on port 'x'. The following operations are possible:
16 *
17 * open do nothing, set up default IEEE 1284 protocol to be COMPAT
18 * close release port and unregister device (if necessary)
19 * ioctl
20 * EXCL register device exclusively (may fail)
21 * CLAIM (register device first time) parport_claim_or_block
22 * RELEASE parport_release
23 * SETMODE set the IEEE 1284 protocol to use for read/write
24 * SETPHASE set the IEEE 1284 phase of a particular mode. Not to be
25 * confused with ioctl(fd, SETPHASER, &stun). ;-)
26 * DATADIR data_forward / data_reverse
27 * WDATA write_data
28 * RDATA read_data
29 * WCONTROL write_control
30 * RCONTROL read_control
31 * FCONTROL frob_control
32 * RSTATUS read_status
33 * NEGOT parport_negotiate
34 * YIELD parport_yield_blocking
35 * WCTLONIRQ on interrupt, set control lines
36 * CLRIRQ clear (and return) interrupt count
37 * SETTIME sets device timeout (struct timeval)
38 * GETTIME gets device timeout (struct timeval)
39 * GETMODES gets hardware supported modes (unsigned int)
40 * GETMODE gets the current IEEE1284 mode
41 * GETPHASE gets the current IEEE1284 phase
42 * GETFLAGS gets current (user-visible) flags
43 * SETFLAGS sets current (user-visible) flags
44 * read/write read or write in current IEEE 1284 protocol
45 * select wait for interrupt (in readfds)
46 *
47 * Changes:
48 * Added SETTIME/GETTIME ioctl, Fred Barnes, 1999.
49 *
50 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 2000/08/25
51 * - On error, copy_from_user and copy_to_user do not return -EFAULT,
52 * They return the positive number of bytes *not* copied due to address
53 * space errors.
54 *
55 * Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <frmb2@ukc.ac.uk>, 03/01/2001.
56 * Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001
57 */
58
59#include <linux/module.h>
60#include <linux/init.h>
61#include <linux/sched.h>
62#include <linux/device.h>
63#include <linux/ioctl.h>
64#include <linux/parport.h>
65#include <linux/ctype.h>
66#include <linux/poll.h>
67#include <linux/slab.h>
68#include <linux/major.h>
69#include <linux/ppdev.h>
70#include <linux/mutex.h>
71#include <linux/uaccess.h>
72#include <linux/compat.h>
73
74#define PP_VERSION "ppdev: user-space parallel port driver"
75#define CHRDEV "ppdev"
76
77struct pp_struct {
78 struct pardevice *pdev;
79 wait_queue_head_t irq_wait;
80 atomic_t irqc;
81 unsigned int flags;
82 int irqresponse;
83 unsigned char irqctl;
84 struct ieee1284_info state;
85 struct ieee1284_info saved_state;
86 long default_inactivity;
87 int index;
88};
89
90/* should we use PARDEVICE_MAX here? */
91static struct device *devices[PARPORT_MAX];
92
93static DEFINE_IDA(ida_index);
94
95/* pp_struct.flags bitfields */
96#define PP_CLAIMED (1<<0)
97#define PP_EXCL (1<<1)
98
99/* Other constants */
100#define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */
101#define PP_BUFFER_SIZE 1024
102#define PARDEVICE_MAX 8
103
104/* ROUND_UP macro from fs/select.c */
105#define ROUND_UP(x,y) (((x)+(y)-1)/(y))
106
107static DEFINE_MUTEX(pp_do_mutex);
108
109/* define fixed sized ioctl cmd for y2038 migration */
110#define PPGETTIME32 _IOR(PP_IOCTL, 0x95, s32[2])
111#define PPSETTIME32 _IOW(PP_IOCTL, 0x96, s32[2])
112#define PPGETTIME64 _IOR(PP_IOCTL, 0x95, s64[2])
113#define PPSETTIME64 _IOW(PP_IOCTL, 0x96, s64[2])
114
115static inline void pp_enable_irq(struct pp_struct *pp)
116{
117 struct parport *port = pp->pdev->port;
118
119 port->ops->enable_irq(port);
120}
121
122static ssize_t pp_read(struct file *file, char __user *buf, size_t count,
123 loff_t *ppos)
124{
125 unsigned int minor = iminor(file_inode(file));
126 struct pp_struct *pp = file->private_data;
127 char *kbuffer;
128 ssize_t bytes_read = 0;
129 struct parport *pport;
130 int mode;
131
132 if (!(pp->flags & PP_CLAIMED)) {
133 /* Don't have the port claimed */
134 pr_debug(CHRDEV "%x: claim the port first\n", minor);
135 return -EINVAL;
136 }
137
138 /* Trivial case. */
139 if (count == 0)
140 return 0;
141
142 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
143 if (!kbuffer)
144 return -ENOMEM;
145 pport = pp->pdev->port;
146 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
147
148 parport_set_timeout(pp->pdev,
149 (file->f_flags & O_NONBLOCK) ?
150 PARPORT_INACTIVITY_O_NONBLOCK :
151 pp->default_inactivity);
152
153 while (bytes_read == 0) {
154 ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE);
155
156 if (mode == IEEE1284_MODE_EPP) {
157 /* various specials for EPP mode */
158 int flags = 0;
159 size_t (*fn)(struct parport *, void *, size_t, int);
160
161 if (pp->flags & PP_W91284PIC)
162 flags |= PARPORT_W91284PIC;
163 if (pp->flags & PP_FASTREAD)
164 flags |= PARPORT_EPP_FAST;
165 if (pport->ieee1284.mode & IEEE1284_ADDR)
166 fn = pport->ops->epp_read_addr;
167 else
168 fn = pport->ops->epp_read_data;
169 bytes_read = (*fn)(pport, kbuffer, need, flags);
170 } else {
171 bytes_read = parport_read(pport, kbuffer, need);
172 }
173
174 if (bytes_read != 0)
175 break;
176
177 if (file->f_flags & O_NONBLOCK) {
178 bytes_read = -EAGAIN;
179 break;
180 }
181
182 if (signal_pending(current)) {
183 bytes_read = -ERESTARTSYS;
184 break;
185 }
186
187 cond_resched();
188 }
189
190 parport_set_timeout(pp->pdev, pp->default_inactivity);
191
192 if (bytes_read > 0 && copy_to_user(buf, kbuffer, bytes_read))
193 bytes_read = -EFAULT;
194
195 kfree(kbuffer);
196 pp_enable_irq(pp);
197 return bytes_read;
198}
199
200static ssize_t pp_write(struct file *file, const char __user *buf,
201 size_t count, loff_t *ppos)
202{
203 unsigned int minor = iminor(file_inode(file));
204 struct pp_struct *pp = file->private_data;
205 char *kbuffer;
206 ssize_t bytes_written = 0;
207 ssize_t wrote;
208 int mode;
209 struct parport *pport;
210
211 if (!(pp->flags & PP_CLAIMED)) {
212 /* Don't have the port claimed */
213 pr_debug(CHRDEV "%x: claim the port first\n", minor);
214 return -EINVAL;
215 }
216
217 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
218 if (!kbuffer)
219 return -ENOMEM;
220
221 pport = pp->pdev->port;
222 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
223
224 parport_set_timeout(pp->pdev,
225 (file->f_flags & O_NONBLOCK) ?
226 PARPORT_INACTIVITY_O_NONBLOCK :
227 pp->default_inactivity);
228
229 while (bytes_written < count) {
230 ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE);
231
232 if (copy_from_user(kbuffer, buf + bytes_written, n)) {
233 bytes_written = -EFAULT;
234 break;
235 }
236
237 if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) {
238 /* do a fast EPP write */
239 if (pport->ieee1284.mode & IEEE1284_ADDR) {
240 wrote = pport->ops->epp_write_addr(pport,
241 kbuffer, n, PARPORT_EPP_FAST);
242 } else {
243 wrote = pport->ops->epp_write_data(pport,
244 kbuffer, n, PARPORT_EPP_FAST);
245 }
246 } else {
247 wrote = parport_write(pp->pdev->port, kbuffer, n);
248 }
249
250 if (wrote <= 0) {
251 if (!bytes_written)
252 bytes_written = wrote;
253 break;
254 }
255
256 bytes_written += wrote;
257
258 if (file->f_flags & O_NONBLOCK) {
259 if (!bytes_written)
260 bytes_written = -EAGAIN;
261 break;
262 }
263
264 if (signal_pending(current))
265 break;
266
267 cond_resched();
268 }
269
270 parport_set_timeout(pp->pdev, pp->default_inactivity);
271
272 kfree(kbuffer);
273 pp_enable_irq(pp);
274 return bytes_written;
275}
276
277static void pp_irq(void *private)
278{
279 struct pp_struct *pp = private;
280
281 if (pp->irqresponse) {
282 parport_write_control(pp->pdev->port, pp->irqctl);
283 pp->irqresponse = 0;
284 }
285
286 atomic_inc(&pp->irqc);
287 wake_up_interruptible(&pp->irq_wait);
288}
289
290static int register_device(int minor, struct pp_struct *pp)
291{
292 struct parport *port;
293 struct pardevice *pdev = NULL;
294 char *name;
295 struct pardev_cb ppdev_cb;
296 int rc = 0, index;
297
298 name = kasprintf(GFP_KERNEL, CHRDEV "%x", minor);
299 if (name == NULL)
300 return -ENOMEM;
301
302 port = parport_find_number(minor);
303 if (!port) {
304 pr_warn("%s: no associated port!\n", name);
305 rc = -ENXIO;
306 goto err;
307 }
308
309 index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL);
310 memset(&ppdev_cb, 0, sizeof(ppdev_cb));
311 ppdev_cb.irq_func = pp_irq;
312 ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0;
313 ppdev_cb.private = pp;
314 pdev = parport_register_dev_model(port, name, &ppdev_cb, index);
315 parport_put_port(port);
316
317 if (!pdev) {
318 pr_warn("%s: failed to register device!\n", name);
319 rc = -ENXIO;
320 ida_simple_remove(&ida_index, index);
321 goto err;
322 }
323
324 pp->pdev = pdev;
325 pp->index = index;
326 dev_dbg(&pdev->dev, "registered pardevice\n");
327err:
328 kfree(name);
329 return rc;
330}
331
332static enum ieee1284_phase init_phase(int mode)
333{
334 switch (mode & ~(IEEE1284_DEVICEID
335 | IEEE1284_ADDR)) {
336 case IEEE1284_MODE_NIBBLE:
337 case IEEE1284_MODE_BYTE:
338 return IEEE1284_PH_REV_IDLE;
339 }
340 return IEEE1284_PH_FWD_IDLE;
341}
342
343static int pp_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec)
344{
345 long to_jiffies;
346
347 if ((tv_sec < 0) || (tv_usec < 0))
348 return -EINVAL;
349
350 to_jiffies = usecs_to_jiffies(tv_usec);
351 to_jiffies += tv_sec * HZ;
352 if (to_jiffies <= 0)
353 return -EINVAL;
354
355 pdev->timeout = to_jiffies;
356 return 0;
357}
358
359static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
360{
361 unsigned int minor = iminor(file_inode(file));
362 struct pp_struct *pp = file->private_data;
363 struct parport *port;
364 void __user *argp = (void __user *)arg;
365
366 /* First handle the cases that don't take arguments. */
367 switch (cmd) {
368 case PPCLAIM:
369 {
370 struct ieee1284_info *info;
371 int ret;
372
373 if (pp->flags & PP_CLAIMED) {
374 dev_dbg(&pp->pdev->dev, "you've already got it!\n");
375 return -EINVAL;
376 }
377
378 /* Deferred device registration. */
379 if (!pp->pdev) {
380 int err = register_device(minor, pp);
381
382 if (err)
383 return err;
384 }
385
386 ret = parport_claim_or_block(pp->pdev);
387 if (ret < 0)
388 return ret;
389
390 pp->flags |= PP_CLAIMED;
391
392 /* For interrupt-reporting to work, we need to be
393 * informed of each interrupt. */
394 pp_enable_irq(pp);
395
396 /* We may need to fix up the state machine. */
397 info = &pp->pdev->port->ieee1284;
398 pp->saved_state.mode = info->mode;
399 pp->saved_state.phase = info->phase;
400 info->mode = pp->state.mode;
401 info->phase = pp->state.phase;
402 pp->default_inactivity = parport_set_timeout(pp->pdev, 0);
403 parport_set_timeout(pp->pdev, pp->default_inactivity);
404
405 return 0;
406 }
407 case PPEXCL:
408 if (pp->pdev) {
409 dev_dbg(&pp->pdev->dev,
410 "too late for PPEXCL; already registered\n");
411 if (pp->flags & PP_EXCL)
412 /* But it's not really an error. */
413 return 0;
414 /* There's no chance of making the driver happy. */
415 return -EINVAL;
416 }
417
418 /* Just remember to register the device exclusively
419 * when we finally do the registration. */
420 pp->flags |= PP_EXCL;
421 return 0;
422 case PPSETMODE:
423 {
424 int mode;
425
426 if (copy_from_user(&mode, argp, sizeof(mode)))
427 return -EFAULT;
428 /* FIXME: validate mode */
429 pp->state.mode = mode;
430 pp->state.phase = init_phase(mode);
431
432 if (pp->flags & PP_CLAIMED) {
433 pp->pdev->port->ieee1284.mode = mode;
434 pp->pdev->port->ieee1284.phase = pp->state.phase;
435 }
436
437 return 0;
438 }
439 case PPGETMODE:
440 {
441 int mode;
442
443 if (pp->flags & PP_CLAIMED)
444 mode = pp->pdev->port->ieee1284.mode;
445 else
446 mode = pp->state.mode;
447
448 if (copy_to_user(argp, &mode, sizeof(mode)))
449 return -EFAULT;
450 return 0;
451 }
452 case PPSETPHASE:
453 {
454 int phase;
455
456 if (copy_from_user(&phase, argp, sizeof(phase)))
457 return -EFAULT;
458
459 /* FIXME: validate phase */
460 pp->state.phase = phase;
461
462 if (pp->flags & PP_CLAIMED)
463 pp->pdev->port->ieee1284.phase = phase;
464
465 return 0;
466 }
467 case PPGETPHASE:
468 {
469 int phase;
470
471 if (pp->flags & PP_CLAIMED)
472 phase = pp->pdev->port->ieee1284.phase;
473 else
474 phase = pp->state.phase;
475 if (copy_to_user(argp, &phase, sizeof(phase)))
476 return -EFAULT;
477 return 0;
478 }
479 case PPGETMODES:
480 {
481 unsigned int modes;
482
483 port = parport_find_number(minor);
484 if (!port)
485 return -ENODEV;
486
487 modes = port->modes;
488 parport_put_port(port);
489 if (copy_to_user(argp, &modes, sizeof(modes)))
490 return -EFAULT;
491 return 0;
492 }
493 case PPSETFLAGS:
494 {
495 int uflags;
496
497 if (copy_from_user(&uflags, argp, sizeof(uflags)))
498 return -EFAULT;
499 pp->flags &= ~PP_FLAGMASK;
500 pp->flags |= (uflags & PP_FLAGMASK);
501 return 0;
502 }
503 case PPGETFLAGS:
504 {
505 int uflags;
506
507 uflags = pp->flags & PP_FLAGMASK;
508 if (copy_to_user(argp, &uflags, sizeof(uflags)))
509 return -EFAULT;
510 return 0;
511 }
512 } /* end switch() */
513
514 /* Everything else requires the port to be claimed, so check
515 * that now. */
516 if ((pp->flags & PP_CLAIMED) == 0) {
517 pr_debug(CHRDEV "%x: claim the port first\n", minor);
518 return -EINVAL;
519 }
520
521 port = pp->pdev->port;
522 switch (cmd) {
523 struct ieee1284_info *info;
524 unsigned char reg;
525 unsigned char mask;
526 int mode;
527 s32 time32[2];
528 s64 time64[2];
529 struct timespec64 ts;
530 int ret;
531
532 case PPRSTATUS:
533 reg = parport_read_status(port);
534 if (copy_to_user(argp, ®, sizeof(reg)))
535 return -EFAULT;
536 return 0;
537 case PPRDATA:
538 reg = parport_read_data(port);
539 if (copy_to_user(argp, ®, sizeof(reg)))
540 return -EFAULT;
541 return 0;
542 case PPRCONTROL:
543 reg = parport_read_control(port);
544 if (copy_to_user(argp, ®, sizeof(reg)))
545 return -EFAULT;
546 return 0;
547 case PPYIELD:
548 parport_yield_blocking(pp->pdev);
549 return 0;
550
551 case PPRELEASE:
552 /* Save the state machine's state. */
553 info = &pp->pdev->port->ieee1284;
554 pp->state.mode = info->mode;
555 pp->state.phase = info->phase;
556 info->mode = pp->saved_state.mode;
557 info->phase = pp->saved_state.phase;
558 parport_release(pp->pdev);
559 pp->flags &= ~PP_CLAIMED;
560 return 0;
561
562 case PPWCONTROL:
563 if (copy_from_user(®, argp, sizeof(reg)))
564 return -EFAULT;
565 parport_write_control(port, reg);
566 return 0;
567
568 case PPWDATA:
569 if (copy_from_user(®, argp, sizeof(reg)))
570 return -EFAULT;
571 parport_write_data(port, reg);
572 return 0;
573
574 case PPFCONTROL:
575 if (copy_from_user(&mask, argp,
576 sizeof(mask)))
577 return -EFAULT;
578 if (copy_from_user(®, 1 + (unsigned char __user *) arg,
579 sizeof(reg)))
580 return -EFAULT;
581 parport_frob_control(port, mask, reg);
582 return 0;
583
584 case PPDATADIR:
585 if (copy_from_user(&mode, argp, sizeof(mode)))
586 return -EFAULT;
587 if (mode)
588 port->ops->data_reverse(port);
589 else
590 port->ops->data_forward(port);
591 return 0;
592
593 case PPNEGOT:
594 if (copy_from_user(&mode, argp, sizeof(mode)))
595 return -EFAULT;
596 switch ((ret = parport_negotiate(port, mode))) {
597 case 0: break;
598 case -1: /* handshake failed, peripheral not IEEE 1284 */
599 ret = -EIO;
600 break;
601 case 1: /* handshake succeeded, peripheral rejected mode */
602 ret = -ENXIO;
603 break;
604 }
605 pp_enable_irq(pp);
606 return ret;
607
608 case PPWCTLONIRQ:
609 if (copy_from_user(®, argp, sizeof(reg)))
610 return -EFAULT;
611
612 /* Remember what to set the control lines to, for next
613 * time we get an interrupt. */
614 pp->irqctl = reg;
615 pp->irqresponse = 1;
616 return 0;
617
618 case PPCLRIRQ:
619 ret = atomic_read(&pp->irqc);
620 if (copy_to_user(argp, &ret, sizeof(ret)))
621 return -EFAULT;
622 atomic_sub(ret, &pp->irqc);
623 return 0;
624
625 case PPSETTIME32:
626 if (copy_from_user(time32, argp, sizeof(time32)))
627 return -EFAULT;
628
629 return pp_set_timeout(pp->pdev, time32[0], time32[1]);
630
631 case PPSETTIME64:
632 if (copy_from_user(time64, argp, sizeof(time64)))
633 return -EFAULT;
634
635 return pp_set_timeout(pp->pdev, time64[0], time64[1]);
636
637 case PPGETTIME32:
638 jiffies_to_timespec64(pp->pdev->timeout, &ts);
639 time32[0] = ts.tv_sec;
640 time32[1] = ts.tv_nsec / NSEC_PER_USEC;
641 if ((time32[0] < 0) || (time32[1] < 0))
642 return -EINVAL;
643
644 if (copy_to_user(argp, time32, sizeof(time32)))
645 return -EFAULT;
646
647 return 0;
648
649 case PPGETTIME64:
650 jiffies_to_timespec64(pp->pdev->timeout, &ts);
651 time64[0] = ts.tv_sec;
652 time64[1] = ts.tv_nsec / NSEC_PER_USEC;
653 if ((time64[0] < 0) || (time64[1] < 0))
654 return -EINVAL;
655
656 if (copy_to_user(argp, time64, sizeof(time64)))
657 return -EFAULT;
658
659 return 0;
660
661 default:
662 dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd);
663 return -EINVAL;
664 }
665
666 /* Keep the compiler happy */
667 return 0;
668}
669
670static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
671{
672 long ret;
673
674 mutex_lock(&pp_do_mutex);
675 ret = pp_do_ioctl(file, cmd, arg);
676 mutex_unlock(&pp_do_mutex);
677 return ret;
678}
679
680#ifdef CONFIG_COMPAT
681static long pp_compat_ioctl(struct file *file, unsigned int cmd,
682 unsigned long arg)
683{
684 return pp_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
685}
686#endif
687
688static int pp_open(struct inode *inode, struct file *file)
689{
690 unsigned int minor = iminor(inode);
691 struct pp_struct *pp;
692
693 if (minor >= PARPORT_MAX)
694 return -ENXIO;
695
696 pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL);
697 if (!pp)
698 return -ENOMEM;
699
700 pp->state.mode = IEEE1284_MODE_COMPAT;
701 pp->state.phase = init_phase(pp->state.mode);
702 pp->flags = 0;
703 pp->irqresponse = 0;
704 atomic_set(&pp->irqc, 0);
705 init_waitqueue_head(&pp->irq_wait);
706
707 /* Defer the actual device registration until the first claim.
708 * That way, we know whether or not the driver wants to have
709 * exclusive access to the port (PPEXCL).
710 */
711 pp->pdev = NULL;
712 file->private_data = pp;
713
714 return 0;
715}
716
717static int pp_release(struct inode *inode, struct file *file)
718{
719 unsigned int minor = iminor(inode);
720 struct pp_struct *pp = file->private_data;
721 int compat_negot;
722
723 compat_negot = 0;
724 if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
725 (pp->state.mode != IEEE1284_MODE_COMPAT)) {
726 struct ieee1284_info *info;
727
728 /* parport released, but not in compatibility mode */
729 parport_claim_or_block(pp->pdev);
730 pp->flags |= PP_CLAIMED;
731 info = &pp->pdev->port->ieee1284;
732 pp->saved_state.mode = info->mode;
733 pp->saved_state.phase = info->phase;
734 info->mode = pp->state.mode;
735 info->phase = pp->state.phase;
736 compat_negot = 1;
737 } else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
738 (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
739 compat_negot = 2;
740 }
741 if (compat_negot) {
742 parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT);
743 dev_dbg(&pp->pdev->dev,
744 "negotiated back to compatibility mode because user-space forgot\n");
745 }
746
747 if (pp->flags & PP_CLAIMED) {
748 struct ieee1284_info *info;
749
750 info = &pp->pdev->port->ieee1284;
751 pp->state.mode = info->mode;
752 pp->state.phase = info->phase;
753 info->mode = pp->saved_state.mode;
754 info->phase = pp->saved_state.phase;
755 parport_release(pp->pdev);
756 if (compat_negot != 1) {
757 pr_debug(CHRDEV "%x: released pardevice "
758 "because user-space forgot\n", minor);
759 }
760 }
761
762 if (pp->pdev) {
763 parport_unregister_device(pp->pdev);
764 ida_simple_remove(&ida_index, pp->index);
765 pp->pdev = NULL;
766 pr_debug(CHRDEV "%x: unregistered pardevice\n", minor);
767 }
768
769 kfree(pp);
770
771 return 0;
772}
773
774/* No kernel lock held - fine */
775static unsigned int pp_poll(struct file *file, poll_table *wait)
776{
777 struct pp_struct *pp = file->private_data;
778 unsigned int mask = 0;
779
780 poll_wait(file, &pp->irq_wait, wait);
781 if (atomic_read(&pp->irqc))
782 mask |= POLLIN | POLLRDNORM;
783
784 return mask;
785}
786
787static struct class *ppdev_class;
788
789static const struct file_operations pp_fops = {
790 .owner = THIS_MODULE,
791 .llseek = no_llseek,
792 .read = pp_read,
793 .write = pp_write,
794 .poll = pp_poll,
795 .unlocked_ioctl = pp_ioctl,
796#ifdef CONFIG_COMPAT
797 .compat_ioctl = pp_compat_ioctl,
798#endif
799 .open = pp_open,
800 .release = pp_release,
801};
802
803static void pp_attach(struct parport *port)
804{
805 struct device *ret;
806
807 if (devices[port->number])
808 return;
809
810 ret = device_create(ppdev_class, port->dev,
811 MKDEV(PP_MAJOR, port->number), NULL,
812 "parport%d", port->number);
813 if (IS_ERR(ret)) {
814 pr_err("Failed to create device parport%d\n",
815 port->number);
816 return;
817 }
818 devices[port->number] = ret;
819}
820
821static void pp_detach(struct parport *port)
822{
823 if (!devices[port->number])
824 return;
825
826 device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number));
827 devices[port->number] = NULL;
828}
829
830static int pp_probe(struct pardevice *par_dev)
831{
832 struct device_driver *drv = par_dev->dev.driver;
833 int len = strlen(drv->name);
834
835 if (strncmp(par_dev->name, drv->name, len))
836 return -ENODEV;
837
838 return 0;
839}
840
841static struct parport_driver pp_driver = {
842 .name = CHRDEV,
843 .probe = pp_probe,
844 .match_port = pp_attach,
845 .detach = pp_detach,
846 .devmodel = true,
847};
848
849static int __init ppdev_init(void)
850{
851 int err = 0;
852
853 if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) {
854 pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR);
855 return -EIO;
856 }
857 ppdev_class = class_create(THIS_MODULE, CHRDEV);
858 if (IS_ERR(ppdev_class)) {
859 err = PTR_ERR(ppdev_class);
860 goto out_chrdev;
861 }
862 err = parport_register_driver(&pp_driver);
863 if (err < 0) {
864 pr_warn(CHRDEV ": unable to register with parport\n");
865 goto out_class;
866 }
867
868 pr_info(PP_VERSION "\n");
869 goto out;
870
871out_class:
872 class_destroy(ppdev_class);
873out_chrdev:
874 unregister_chrdev(PP_MAJOR, CHRDEV);
875out:
876 return err;
877}
878
879static void __exit ppdev_cleanup(void)
880{
881 /* Clean up all parport stuff */
882 parport_unregister_driver(&pp_driver);
883 class_destroy(ppdev_class);
884 unregister_chrdev(PP_MAJOR, CHRDEV);
885}
886
887module_init(ppdev_init);
888module_exit(ppdev_cleanup);
889
890MODULE_LICENSE("GPL");
891MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);