projects/linux·blob assoc-array-fixes · refs

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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * linux/drivers/char/ppdev.c
4 *
5 * This is the code behind /dev/parport* -- it allows a user-space
6 * application to use the parport subsystem.
7 *
8 * Copyright (C) 1998-2000, 2002 Tim Waugh <[email protected]>
9 *
10 * A /dev/parportx device node represents an arbitrary device
11 * on port 'x'. The following operations are possible:
12 *
13 * open do nothing, set up default IEEE 1284 protocol to be COMPAT
14 * close release port and unregister device (if necessary)
15 * ioctl
16 * EXCL register device exclusively (may fail)
17 * CLAIM (register device first time) parport_claim_or_block
18 * RELEASE parport_release
19 * SETMODE set the IEEE 1284 protocol to use for read/write
20 * SETPHASE set the IEEE 1284 phase of a particular mode. Not to be
21 * confused with ioctl(fd, SETPHASER, &stun). ;-)
22 * DATADIR data_forward / data_reverse
23 * WDATA write_data
24 * RDATA read_data
25 * WCONTROL write_control
26 * RCONTROL read_control
27 * FCONTROL frob_control
28 * RSTATUS read_status
29 * NEGOT parport_negotiate
30 * YIELD parport_yield_blocking
31 * WCTLONIRQ on interrupt, set control lines
32 * CLRIRQ clear (and return) interrupt count
33 * SETTIME sets device timeout (struct timeval)
34 * GETTIME gets device timeout (struct timeval)
35 * GETMODES gets hardware supported modes (unsigned int)
36 * GETMODE gets the current IEEE1284 mode
37 * GETPHASE gets the current IEEE1284 phase
38 * GETFLAGS gets current (user-visible) flags
39 * SETFLAGS sets current (user-visible) flags
40 * read/write read or write in current IEEE 1284 protocol
41 * select wait for interrupt (in readfds)
42 *
43 * Changes:
44 * Added SETTIME/GETTIME ioctl, Fred Barnes, 1999.
45 *
46 * Arnaldo Carvalho de Melo <[email protected]> 2000/08/25
47 * - On error, copy_from_user and copy_to_user do not return -EFAULT,
48 * They return the positive number of bytes *not* copied due to address
49 * space errors.
50 *
51 * Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <[email protected]>, 03/01/2001.
52 * Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001
53 */
54
55#include <linux/module.h>
56#include <linux/init.h>
57#include <linux/sched/signal.h>
58#include <linux/device.h>
59#include <linux/ioctl.h>
60#include <linux/parport.h>
61#include <linux/ctype.h>
62#include <linux/poll.h>
63#include <linux/slab.h>
64#include <linux/major.h>
65#include <linux/ppdev.h>
66#include <linux/mutex.h>
67#include <linux/uaccess.h>
68#include <linux/compat.h>
69
70#define PP_VERSION "ppdev: user-space parallel port driver"
71#define CHRDEV "ppdev"
72
73struct pp_struct {
74 struct pardevice *pdev;
75 wait_queue_head_t irq_wait;
76 atomic_t irqc;
77 unsigned int flags;
78 int irqresponse;
79 unsigned char irqctl;
80 struct ieee1284_info state;
81 struct ieee1284_info saved_state;
82 long default_inactivity;
83 int index;
84};
85
86/* should we use PARDEVICE_MAX here? */
87static struct device *devices[PARPORT_MAX];
88
89static DEFINE_IDA(ida_index);
90
91/* pp_struct.flags bitfields */
92#define PP_CLAIMED (1<<0)
93#define PP_EXCL (1<<1)
94
95/* Other constants */
96#define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */
97#define PP_BUFFER_SIZE 1024
98#define PARDEVICE_MAX 8
99
100static DEFINE_MUTEX(pp_do_mutex);
101
102/* define fixed sized ioctl cmd for y2038 migration */
103#define PPGETTIME32 _IOR(PP_IOCTL, 0x95, s32[2])
104#define PPSETTIME32 _IOW(PP_IOCTL, 0x96, s32[2])
105#define PPGETTIME64 _IOR(PP_IOCTL, 0x95, s64[2])
106#define PPSETTIME64 _IOW(PP_IOCTL, 0x96, s64[2])
107
108static inline void pp_enable_irq(struct pp_struct *pp)
109{
110 struct parport *port = pp->pdev->port;
111
112 port->ops->enable_irq(port);
113}
114
115static ssize_t pp_read(struct file *file, char __user *buf, size_t count,
116 loff_t *ppos)
117{
118 unsigned int minor = iminor(file_inode(file));
119 struct pp_struct *pp = file->private_data;
120 char *kbuffer;
121 ssize_t bytes_read = 0;
122 struct parport *pport;
123 int mode;
124
125 if (!(pp->flags & PP_CLAIMED)) {
126 /* Don't have the port claimed */
127 pr_debug(CHRDEV "%x: claim the port first\n", minor);
128 return -EINVAL;
129 }
130
131 /* Trivial case. */
132 if (count == 0)
133 return 0;
134
135 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
136 if (!kbuffer)
137 return -ENOMEM;
138 pport = pp->pdev->port;
139 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
140
141 parport_set_timeout(pp->pdev,
142 (file->f_flags & O_NONBLOCK) ?
143 PARPORT_INACTIVITY_O_NONBLOCK :
144 pp->default_inactivity);
145
146 while (bytes_read == 0) {
147 ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE);
148
149 if (mode == IEEE1284_MODE_EPP) {
150 /* various specials for EPP mode */
151 int flags = 0;
152 size_t (*fn)(struct parport *, void *, size_t, int);
153
154 if (pp->flags & PP_W91284PIC)
155 flags |= PARPORT_W91284PIC;
156 if (pp->flags & PP_FASTREAD)
157 flags |= PARPORT_EPP_FAST;
158 if (pport->ieee1284.mode & IEEE1284_ADDR)
159 fn = pport->ops->epp_read_addr;
160 else
161 fn = pport->ops->epp_read_data;
162 bytes_read = (*fn)(pport, kbuffer, need, flags);
163 } else {
164 bytes_read = parport_read(pport, kbuffer, need);
165 }
166
167 if (bytes_read != 0)
168 break;
169
170 if (file->f_flags & O_NONBLOCK) {
171 bytes_read = -EAGAIN;
172 break;
173 }
174
175 if (signal_pending(current)) {
176 bytes_read = -ERESTARTSYS;
177 break;
178 }
179
180 cond_resched();
181 }
182
183 parport_set_timeout(pp->pdev, pp->default_inactivity);
184
185 if (bytes_read > 0 && copy_to_user(buf, kbuffer, bytes_read))
186 bytes_read = -EFAULT;
187
188 kfree(kbuffer);
189 pp_enable_irq(pp);
190 return bytes_read;
191}
192
193static ssize_t pp_write(struct file *file, const char __user *buf,
194 size_t count, loff_t *ppos)
195{
196 unsigned int minor = iminor(file_inode(file));
197 struct pp_struct *pp = file->private_data;
198 char *kbuffer;
199 ssize_t bytes_written = 0;
200 ssize_t wrote;
201 int mode;
202 struct parport *pport;
203
204 if (!(pp->flags & PP_CLAIMED)) {
205 /* Don't have the port claimed */
206 pr_debug(CHRDEV "%x: claim the port first\n", minor);
207 return -EINVAL;
208 }
209
210 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
211 if (!kbuffer)
212 return -ENOMEM;
213
214 pport = pp->pdev->port;
215 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
216
217 parport_set_timeout(pp->pdev,
218 (file->f_flags & O_NONBLOCK) ?
219 PARPORT_INACTIVITY_O_NONBLOCK :
220 pp->default_inactivity);
221
222 while (bytes_written < count) {
223 ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE);
224
225 if (copy_from_user(kbuffer, buf + bytes_written, n)) {
226 bytes_written = -EFAULT;
227 break;
228 }
229
230 if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) {
231 /* do a fast EPP write */
232 if (pport->ieee1284.mode & IEEE1284_ADDR) {
233 wrote = pport->ops->epp_write_addr(pport,
234 kbuffer, n, PARPORT_EPP_FAST);
235 } else {
236 wrote = pport->ops->epp_write_data(pport,
237 kbuffer, n, PARPORT_EPP_FAST);
238 }
239 } else {
240 wrote = parport_write(pp->pdev->port, kbuffer, n);
241 }
242
243 if (wrote <= 0) {
244 if (!bytes_written)
245 bytes_written = wrote;
246 break;
247 }
248
249 bytes_written += wrote;
250
251 if (file->f_flags & O_NONBLOCK) {
252 if (!bytes_written)
253 bytes_written = -EAGAIN;
254 break;
255 }
256
257 if (signal_pending(current))
258 break;
259
260 cond_resched();
261 }
262
263 parport_set_timeout(pp->pdev, pp->default_inactivity);
264
265 kfree(kbuffer);
266 pp_enable_irq(pp);
267 return bytes_written;
268}
269
270static void pp_irq(void *private)
271{
272 struct pp_struct *pp = private;
273
274 if (pp->irqresponse) {
275 parport_write_control(pp->pdev->port, pp->irqctl);
276 pp->irqresponse = 0;
277 }
278
279 atomic_inc(&pp->irqc);
280 wake_up_interruptible(&pp->irq_wait);
281}
282
283static int register_device(int minor, struct pp_struct *pp)
284{
285 struct parport *port;
286 struct pardevice *pdev = NULL;
287 char *name;
288 struct pardev_cb ppdev_cb;
289 int rc = 0, index;
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 pr_warn("%s: no associated port!\n", name);
298 rc = -ENXIO;
299 goto err_free_name;
300 }
301
302 index = ida_alloc(&ida_index, GFP_KERNEL);
303 if (index < 0) {
304 pr_warn("%s: failed to get index!\n", name);
305 rc = index;
306 goto err_put_port;
307 }
308
309 memset(&ppdev_cb, 0, sizeof(ppdev_cb));
310 ppdev_cb.irq_func = pp_irq;
311 ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0;
312 ppdev_cb.private = pp;
313 pdev = parport_register_dev_model(port, name, &ppdev_cb, index);
314
315 if (!pdev) {
316 pr_warn("%s: failed to register device!\n", name);
317 rc = -ENXIO;
318 ida_free(&ida_index, index);
319 goto err_put_port;
320 }
321
322 pp->pdev = pdev;
323 pp->index = index;
324 dev_dbg(&pdev->dev, "registered pardevice\n");
325err_put_port:
326 parport_put_port(port);
327err_free_name:
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, s64 tv_sec, s64 tv_usec)
344{
345 struct timespec64 ts;
346 long to_jiffies;
347
348 if (tv_sec < 0 || tv_usec < 0 || tv_usec >= USEC_PER_SEC)
349 return -EINVAL;
350
351 ts.tv_sec = tv_sec;
352 ts.tv_nsec = tv_usec * NSEC_PER_USEC;
353 to_jiffies = timespec64_to_jiffies(&ts);
354 if (to_jiffies <= 0)
355 return -EINVAL;
356
357 pdev->timeout = to_jiffies;
358 return 0;
359}
360
361static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
362{
363 unsigned int minor = iminor(file_inode(file));
364 struct pp_struct *pp = file->private_data;
365 struct parport *port;
366 void __user *argp = (void __user *)arg;
367 struct ieee1284_info *info;
368 unsigned char reg;
369 unsigned char mask;
370 int mode;
371 s32 time32[2];
372 s64 time64[2];
373 struct timespec64 ts;
374 int ret;
375
376 /* First handle the cases that don't take arguments. */
377 switch (cmd) {
378 case PPCLAIM:
379 {
380 if (pp->flags & PP_CLAIMED) {
381 dev_dbg(&pp->pdev->dev, "you've already got it!\n");
382 return -EINVAL;
383 }
384
385 /* Deferred device registration. */
386 if (!pp->pdev) {
387 int err = register_device(minor, pp);
388
389 if (err)
390 return err;
391 }
392
393 ret = parport_claim_or_block(pp->pdev);
394 if (ret < 0)
395 return ret;
396
397 pp->flags |= PP_CLAIMED;
398
399 /* For interrupt-reporting to work, we need to be
400 * informed of each interrupt. */
401 pp_enable_irq(pp);
402
403 /* We may need to fix up the state machine. */
404 info = &pp->pdev->port->ieee1284;
405 pp->saved_state.mode = info->mode;
406 pp->saved_state.phase = info->phase;
407 info->mode = pp->state.mode;
408 info->phase = pp->state.phase;
409 pp->default_inactivity = parport_set_timeout(pp->pdev, 0);
410 parport_set_timeout(pp->pdev, pp->default_inactivity);
411
412 return 0;
413 }
414 case PPEXCL:
415 if (pp->pdev) {
416 dev_dbg(&pp->pdev->dev,
417 "too late for PPEXCL; already registered\n");
418 if (pp->flags & PP_EXCL)
419 /* But it's not really an error. */
420 return 0;
421 /* There's no chance of making the driver happy. */
422 return -EINVAL;
423 }
424
425 /* Just remember to register the device exclusively
426 * when we finally do the registration. */
427 pp->flags |= PP_EXCL;
428 return 0;
429 case PPSETMODE:
430 {
431 int mode;
432
433 if (copy_from_user(&mode, argp, sizeof(mode)))
434 return -EFAULT;
435 /* FIXME: validate mode */
436 pp->state.mode = mode;
437 pp->state.phase = init_phase(mode);
438
439 if (pp->flags & PP_CLAIMED) {
440 pp->pdev->port->ieee1284.mode = mode;
441 pp->pdev->port->ieee1284.phase = pp->state.phase;
442 }
443
444 return 0;
445 }
446 case PPGETMODE:
447 {
448 int mode;
449
450 if (pp->flags & PP_CLAIMED)
451 mode = pp->pdev->port->ieee1284.mode;
452 else
453 mode = pp->state.mode;
454
455 if (copy_to_user(argp, &mode, sizeof(mode)))
456 return -EFAULT;
457 return 0;
458 }
459 case PPSETPHASE:
460 {
461 int phase;
462
463 if (copy_from_user(&phase, argp, sizeof(phase)))
464 return -EFAULT;
465
466 /* FIXME: validate phase */
467 pp->state.phase = phase;
468
469 if (pp->flags & PP_CLAIMED)
470 pp->pdev->port->ieee1284.phase = phase;
471
472 return 0;
473 }
474 case PPGETPHASE:
475 {
476 int phase;
477
478 if (pp->flags & PP_CLAIMED)
479 phase = pp->pdev->port->ieee1284.phase;
480 else
481 phase = pp->state.phase;
482 if (copy_to_user(argp, &phase, sizeof(phase)))
483 return -EFAULT;
484 return 0;
485 }
486 case PPGETMODES:
487 {
488 unsigned int modes;
489
490 port = parport_find_number(minor);
491 if (!port)
492 return -ENODEV;
493
494 modes = port->modes;
495 parport_put_port(port);
496 if (copy_to_user(argp, &modes, sizeof(modes)))
497 return -EFAULT;
498 return 0;
499 }
500 case PPSETFLAGS:
501 {
502 int uflags;
503
504 if (copy_from_user(&uflags, argp, sizeof(uflags)))
505 return -EFAULT;
506 pp->flags &= ~PP_FLAGMASK;
507 pp->flags |= (uflags & PP_FLAGMASK);
508 return 0;
509 }
510 case PPGETFLAGS:
511 {
512 int uflags;
513
514 uflags = pp->flags & PP_FLAGMASK;
515 if (copy_to_user(argp, &uflags, sizeof(uflags)))
516 return -EFAULT;
517 return 0;
518 }
519 } /* end switch() */
520
521 /* Everything else requires the port to be claimed, so check
522 * that now. */
523 if ((pp->flags & PP_CLAIMED) == 0) {
524 pr_debug(CHRDEV "%x: claim the port first\n", minor);
525 return -EINVAL;
526 }
527
528 port = pp->pdev->port;
529 switch (cmd) {
530 case PPRSTATUS:
531 reg = parport_read_status(port);
532 if (copy_to_user(argp, &reg, sizeof(reg)))
533 return -EFAULT;
534 return 0;
535 case PPRDATA:
536 reg = parport_read_data(port);
537 if (copy_to_user(argp, &reg, sizeof(reg)))
538 return -EFAULT;
539 return 0;
540 case PPRCONTROL:
541 reg = parport_read_control(port);
542 if (copy_to_user(argp, &reg, sizeof(reg)))
543 return -EFAULT;
544 return 0;
545 case PPYIELD:
546 parport_yield_blocking(pp->pdev);
547 return 0;
548
549 case PPRELEASE:
550 /* Save the state machine's state. */
551 info = &pp->pdev->port->ieee1284;
552 pp->state.mode = info->mode;
553 pp->state.phase = info->phase;
554 info->mode = pp->saved_state.mode;
555 info->phase = pp->saved_state.phase;
556 parport_release(pp->pdev);
557 pp->flags &= ~PP_CLAIMED;
558 return 0;
559
560 case PPWCONTROL:
561 if (copy_from_user(&reg, argp, sizeof(reg)))
562 return -EFAULT;
563 parport_write_control(port, reg);
564 return 0;
565
566 case PPWDATA:
567 if (copy_from_user(&reg, argp, sizeof(reg)))
568 return -EFAULT;
569 parport_write_data(port, reg);
570 return 0;
571
572 case PPFCONTROL:
573 if (copy_from_user(&mask, argp,
574 sizeof(mask)))
575 return -EFAULT;
576 if (copy_from_user(&reg, 1 + (unsigned char __user *) arg,
577 sizeof(reg)))
578 return -EFAULT;
579 parport_frob_control(port, mask, reg);
580 return 0;
581
582 case PPDATADIR:
583 if (copy_from_user(&mode, argp, sizeof(mode)))
584 return -EFAULT;
585 if (mode)
586 port->ops->data_reverse(port);
587 else
588 port->ops->data_forward(port);
589 return 0;
590
591 case PPNEGOT:
592 if (copy_from_user(&mode, argp, sizeof(mode)))
593 return -EFAULT;
594 switch ((ret = parport_negotiate(port, mode))) {
595 case 0: break;
596 case -1: /* handshake failed, peripheral not IEEE 1284 */
597 ret = -EIO;
598 break;
599 case 1: /* handshake succeeded, peripheral rejected mode */
600 ret = -ENXIO;
601 break;
602 }
603 pp_enable_irq(pp);
604 return ret;
605
606 case PPWCTLONIRQ:
607 if (copy_from_user(&reg, argp, sizeof(reg)))
608 return -EFAULT;
609
610 /* Remember what to set the control lines to, for next
611 * time we get an interrupt. */
612 pp->irqctl = reg;
613 pp->irqresponse = 1;
614 return 0;
615
616 case PPCLRIRQ:
617 ret = atomic_read(&pp->irqc);
618 if (copy_to_user(argp, &ret, sizeof(ret)))
619 return -EFAULT;
620 atomic_sub(ret, &pp->irqc);
621 return 0;
622
623 case PPSETTIME32:
624 if (copy_from_user(time32, argp, sizeof(time32)))
625 return -EFAULT;
626
627 if ((time32[0] < 0) || (time32[1] < 0))
628 return -EINVAL;
629
630 return pp_set_timeout(pp->pdev, time32[0], time32[1]);
631
632 case PPSETTIME64:
633 if (copy_from_user(time64, argp, sizeof(time64)))
634 return -EFAULT;
635
636 if ((time64[0] < 0) || (time64[1] < 0))
637 return -EINVAL;
638
639 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
640 time64[1] >>= 32;
641
642 return pp_set_timeout(pp->pdev, time64[0], time64[1]);
643
644 case PPGETTIME32:
645 jiffies_to_timespec64(pp->pdev->timeout, &ts);
646 time32[0] = ts.tv_sec;
647 time32[1] = ts.tv_nsec / NSEC_PER_USEC;
648
649 if (copy_to_user(argp, time32, sizeof(time32)))
650 return -EFAULT;
651
652 return 0;
653
654 case PPGETTIME64:
655 jiffies_to_timespec64(pp->pdev->timeout, &ts);
656 time64[0] = ts.tv_sec;
657 time64[1] = ts.tv_nsec / NSEC_PER_USEC;
658
659 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
660 time64[1] <<= 32;
661
662 if (copy_to_user(argp, time64, sizeof(time64)))
663 return -EFAULT;
664
665 return 0;
666
667 default:
668 dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd);
669 return -EINVAL;
670 }
671
672 /* Keep the compiler happy */
673 return 0;
674}
675
676static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
677{
678 long ret;
679
680 mutex_lock(&pp_do_mutex);
681 ret = pp_do_ioctl(file, cmd, arg);
682 mutex_unlock(&pp_do_mutex);
683 return ret;
684}
685
686static int pp_open(struct inode *inode, struct file *file)
687{
688 unsigned int minor = iminor(inode);
689 struct pp_struct *pp;
690
691 if (minor >= PARPORT_MAX)
692 return -ENXIO;
693
694 pp = kmalloc_obj(struct pp_struct);
695 if (!pp)
696 return -ENOMEM;
697
698 pp->state.mode = IEEE1284_MODE_COMPAT;
699 pp->state.phase = init_phase(pp->state.mode);
700 pp->flags = 0;
701 pp->irqresponse = 0;
702 atomic_set(&pp->irqc, 0);
703 init_waitqueue_head(&pp->irq_wait);
704
705 /* Defer the actual device registration until the first claim.
706 * That way, we know whether or not the driver wants to have
707 * exclusive access to the port (PPEXCL).
708 */
709 pp->pdev = NULL;
710 file->private_data = pp;
711
712 return 0;
713}
714
715static int pp_release(struct inode *inode, struct file *file)
716{
717 unsigned int minor = iminor(inode);
718 struct pp_struct *pp = file->private_data;
719 int compat_negot;
720
721 compat_negot = 0;
722 if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
723 (pp->state.mode != IEEE1284_MODE_COMPAT)) {
724 struct ieee1284_info *info;
725
726 /* parport released, but not in compatibility mode */
727 parport_claim_or_block(pp->pdev);
728 pp->flags |= PP_CLAIMED;
729 info = &pp->pdev->port->ieee1284;
730 pp->saved_state.mode = info->mode;
731 pp->saved_state.phase = info->phase;
732 info->mode = pp->state.mode;
733 info->phase = pp->state.phase;
734 compat_negot = 1;
735 } else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
736 (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
737 compat_negot = 2;
738 }
739 if (compat_negot) {
740 parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT);
741 dev_dbg(&pp->pdev->dev,
742 "negotiated back to compatibility mode because user-space forgot\n");
743 }
744
745 if ((pp->flags & PP_CLAIMED) && pp->pdev) {
746 struct ieee1284_info *info;
747
748 info = &pp->pdev->port->ieee1284;
749 pp->state.mode = info->mode;
750 pp->state.phase = info->phase;
751 info->mode = pp->saved_state.mode;
752 info->phase = pp->saved_state.phase;
753 parport_release(pp->pdev);
754 if (compat_negot != 1) {
755 pr_debug(CHRDEV "%x: released pardevice "
756 "because user-space forgot\n", minor);
757 }
758 }
759
760 if (pp->pdev) {
761 parport_unregister_device(pp->pdev);
762 ida_free(&ida_index, pp->index);
763 pp->pdev = NULL;
764 pr_debug(CHRDEV "%x: unregistered pardevice\n", minor);
765 }
766
767 kfree(pp);
768
769 return 0;
770}
771
772/* No kernel lock held - fine */
773static __poll_t pp_poll(struct file *file, poll_table *wait)
774{
775 struct pp_struct *pp = file->private_data;
776 __poll_t mask = 0;
777
778 poll_wait(file, &pp->irq_wait, wait);
779 if (atomic_read(&pp->irqc))
780 mask |= EPOLLIN | EPOLLRDNORM;
781
782 return mask;
783}
784
785static const struct class ppdev_class = {
786 .name = CHRDEV,
787};
788
789static const struct file_operations pp_fops = {
790 .owner = THIS_MODULE,
791 .read = pp_read,
792 .write = pp_write,
793 .poll = pp_poll,
794 .unlocked_ioctl = pp_ioctl,
795 .compat_ioctl = compat_ptr_ioctl,
796 .open = pp_open,
797 .release = pp_release,
798};
799
800static void pp_attach(struct parport *port)
801{
802 struct device *ret;
803
804 if (devices[port->number])
805 return;
806
807 ret = device_create(&ppdev_class, port->dev,
808 MKDEV(PP_MAJOR, port->number), NULL,
809 "parport%d", port->number);
810 if (IS_ERR(ret)) {
811 pr_err("Failed to create device parport%d\n",
812 port->number);
813 return;
814 }
815 devices[port->number] = ret;
816}
817
818static void pp_detach(struct parport *port)
819{
820 if (!devices[port->number])
821 return;
822
823 device_destroy(&ppdev_class, MKDEV(PP_MAJOR, port->number));
824 devices[port->number] = NULL;
825}
826
827static int pp_probe(struct pardevice *par_dev)
828{
829 struct device_driver *drv = par_dev->dev.driver;
830 int len = strlen(drv->name);
831
832 if (strncmp(par_dev->name, drv->name, len))
833 return -ENODEV;
834
835 return 0;
836}
837
838static struct parport_driver pp_driver = {
839 .name = CHRDEV,
840 .probe = pp_probe,
841 .match_port = pp_attach,
842 .detach = pp_detach,
843};
844
845static int __init ppdev_init(void)
846{
847 int err = 0;
848
849 if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) {
850 pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR);
851 return -EIO;
852 }
853 err = class_register(&ppdev_class);
854 if (err)
855 goto out_chrdev;
856
857 err = parport_register_driver(&pp_driver);
858 if (err < 0) {
859 pr_warn(CHRDEV ": unable to register with parport\n");
860 goto out_class;
861 }
862
863 pr_info(PP_VERSION "\n");
864 goto out;
865
866out_class:
867 class_unregister(&ppdev_class);
868out_chrdev:
869 unregister_chrdev(PP_MAJOR, CHRDEV);
870out:
871 return err;
872}
873
874static void __exit ppdev_cleanup(void)
875{
876 /* Clean up all parport stuff */
877 parport_unregister_driver(&pp_driver);
878 class_unregister(&ppdev_class);
879 unregister_chrdev(PP_MAJOR, CHRDEV);
880}
881
882module_init(ppdev_init);
883module_exit(ppdev_cleanup);
884
885MODULE_DESCRIPTION("Support for user-space parallel port device drivers");
886MODULE_LICENSE("GPL");
887MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);