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 <tim@cyberelk.net>
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 <acme@conectiva.com.br> 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 <frmb2@ukc.ac.uk>, 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
73 struct 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? */
87 static struct device *devices[PARPORT_MAX];
88
89 static 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
100 static 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
pp_enable_irq(struct pp_struct * pp)108 static 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
pp_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)115 static 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
pp_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)193 static 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
pp_irq(void * private)270 static 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
register_device(int minor,struct pp_struct * pp)283 static 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;
300 }
301
302 index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL);
303 memset(&ppdev_cb, 0, sizeof(ppdev_cb));
304 ppdev_cb.irq_func = pp_irq;
305 ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0;
306 ppdev_cb.private = pp;
307 pdev = parport_register_dev_model(port, name, &ppdev_cb, index);
308 parport_put_port(port);
309
310 if (!pdev) {
311 pr_warn("%s: failed to register device!\n", name);
312 rc = -ENXIO;
313 ida_simple_remove(&ida_index, index);
314 goto err;
315 }
316
317 pp->pdev = pdev;
318 pp->index = index;
319 dev_dbg(&pdev->dev, "registered pardevice\n");
320 err:
321 kfree(name);
322 return rc;
323 }
324
init_phase(int mode)325 static enum ieee1284_phase init_phase(int mode)
326 {
327 switch (mode & ~(IEEE1284_DEVICEID
328 | IEEE1284_ADDR)) {
329 case IEEE1284_MODE_NIBBLE:
330 case IEEE1284_MODE_BYTE:
331 return IEEE1284_PH_REV_IDLE;
332 }
333 return IEEE1284_PH_FWD_IDLE;
334 }
335
pp_set_timeout(struct pardevice * pdev,long tv_sec,int tv_usec)336 static int pp_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec)
337 {
338 long to_jiffies;
339
340 if ((tv_sec < 0) || (tv_usec < 0))
341 return -EINVAL;
342
343 to_jiffies = usecs_to_jiffies(tv_usec);
344 to_jiffies += tv_sec * HZ;
345 if (to_jiffies <= 0)
346 return -EINVAL;
347
348 pdev->timeout = to_jiffies;
349 return 0;
350 }
351
pp_do_ioctl(struct file * file,unsigned int cmd,unsigned long arg)352 static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
353 {
354 unsigned int minor = iminor(file_inode(file));
355 struct pp_struct *pp = file->private_data;
356 struct parport *port;
357 void __user *argp = (void __user *)arg;
358 struct ieee1284_info *info;
359 unsigned char reg;
360 unsigned char mask;
361 int mode;
362 s32 time32[2];
363 s64 time64[2];
364 struct timespec64 ts;
365 int ret;
366
367 /* First handle the cases that don't take arguments. */
368 switch (cmd) {
369 case PPCLAIM:
370 {
371 if (pp->flags & PP_CLAIMED) {
372 dev_dbg(&pp->pdev->dev, "you've already got it!\n");
373 return -EINVAL;
374 }
375
376 /* Deferred device registration. */
377 if (!pp->pdev) {
378 int err = register_device(minor, pp);
379
380 if (err)
381 return err;
382 }
383
384 ret = parport_claim_or_block(pp->pdev);
385 if (ret < 0)
386 return ret;
387
388 pp->flags |= PP_CLAIMED;
389
390 /* For interrupt-reporting to work, we need to be
391 * informed of each interrupt. */
392 pp_enable_irq(pp);
393
394 /* We may need to fix up the state machine. */
395 info = &pp->pdev->port->ieee1284;
396 pp->saved_state.mode = info->mode;
397 pp->saved_state.phase = info->phase;
398 info->mode = pp->state.mode;
399 info->phase = pp->state.phase;
400 pp->default_inactivity = parport_set_timeout(pp->pdev, 0);
401 parport_set_timeout(pp->pdev, pp->default_inactivity);
402
403 return 0;
404 }
405 case PPEXCL:
406 if (pp->pdev) {
407 dev_dbg(&pp->pdev->dev,
408 "too late for PPEXCL; already registered\n");
409 if (pp->flags & PP_EXCL)
410 /* But it's not really an error. */
411 return 0;
412 /* There's no chance of making the driver happy. */
413 return -EINVAL;
414 }
415
416 /* Just remember to register the device exclusively
417 * when we finally do the registration. */
418 pp->flags |= PP_EXCL;
419 return 0;
420 case PPSETMODE:
421 {
422 int mode;
423
424 if (copy_from_user(&mode, argp, sizeof(mode)))
425 return -EFAULT;
426 /* FIXME: validate mode */
427 pp->state.mode = mode;
428 pp->state.phase = init_phase(mode);
429
430 if (pp->flags & PP_CLAIMED) {
431 pp->pdev->port->ieee1284.mode = mode;
432 pp->pdev->port->ieee1284.phase = pp->state.phase;
433 }
434
435 return 0;
436 }
437 case PPGETMODE:
438 {
439 int mode;
440
441 if (pp->flags & PP_CLAIMED)
442 mode = pp->pdev->port->ieee1284.mode;
443 else
444 mode = pp->state.mode;
445
446 if (copy_to_user(argp, &mode, sizeof(mode)))
447 return -EFAULT;
448 return 0;
449 }
450 case PPSETPHASE:
451 {
452 int phase;
453
454 if (copy_from_user(&phase, argp, sizeof(phase)))
455 return -EFAULT;
456
457 /* FIXME: validate phase */
458 pp->state.phase = phase;
459
460 if (pp->flags & PP_CLAIMED)
461 pp->pdev->port->ieee1284.phase = phase;
462
463 return 0;
464 }
465 case PPGETPHASE:
466 {
467 int phase;
468
469 if (pp->flags & PP_CLAIMED)
470 phase = pp->pdev->port->ieee1284.phase;
471 else
472 phase = pp->state.phase;
473 if (copy_to_user(argp, &phase, sizeof(phase)))
474 return -EFAULT;
475 return 0;
476 }
477 case PPGETMODES:
478 {
479 unsigned int modes;
480
481 port = parport_find_number(minor);
482 if (!port)
483 return -ENODEV;
484
485 modes = port->modes;
486 parport_put_port(port);
487 if (copy_to_user(argp, &modes, sizeof(modes)))
488 return -EFAULT;
489 return 0;
490 }
491 case PPSETFLAGS:
492 {
493 int uflags;
494
495 if (copy_from_user(&uflags, argp, sizeof(uflags)))
496 return -EFAULT;
497 pp->flags &= ~PP_FLAGMASK;
498 pp->flags |= (uflags & PP_FLAGMASK);
499 return 0;
500 }
501 case PPGETFLAGS:
502 {
503 int uflags;
504
505 uflags = pp->flags & PP_FLAGMASK;
506 if (copy_to_user(argp, &uflags, sizeof(uflags)))
507 return -EFAULT;
508 return 0;
509 }
510 } /* end switch() */
511
512 /* Everything else requires the port to be claimed, so check
513 * that now. */
514 if ((pp->flags & PP_CLAIMED) == 0) {
515 pr_debug(CHRDEV "%x: claim the port first\n", minor);
516 return -EINVAL;
517 }
518
519 port = pp->pdev->port;
520 switch (cmd) {
521 case PPRSTATUS:
522 reg = parport_read_status(port);
523 if (copy_to_user(argp, ®, sizeof(reg)))
524 return -EFAULT;
525 return 0;
526 case PPRDATA:
527 reg = parport_read_data(port);
528 if (copy_to_user(argp, ®, sizeof(reg)))
529 return -EFAULT;
530 return 0;
531 case PPRCONTROL:
532 reg = parport_read_control(port);
533 if (copy_to_user(argp, ®, sizeof(reg)))
534 return -EFAULT;
535 return 0;
536 case PPYIELD:
537 parport_yield_blocking(pp->pdev);
538 return 0;
539
540 case PPRELEASE:
541 /* Save the state machine's state. */
542 info = &pp->pdev->port->ieee1284;
543 pp->state.mode = info->mode;
544 pp->state.phase = info->phase;
545 info->mode = pp->saved_state.mode;
546 info->phase = pp->saved_state.phase;
547 parport_release(pp->pdev);
548 pp->flags &= ~PP_CLAIMED;
549 return 0;
550
551 case PPWCONTROL:
552 if (copy_from_user(®, argp, sizeof(reg)))
553 return -EFAULT;
554 parport_write_control(port, reg);
555 return 0;
556
557 case PPWDATA:
558 if (copy_from_user(®, argp, sizeof(reg)))
559 return -EFAULT;
560 parport_write_data(port, reg);
561 return 0;
562
563 case PPFCONTROL:
564 if (copy_from_user(&mask, argp,
565 sizeof(mask)))
566 return -EFAULT;
567 if (copy_from_user(®, 1 + (unsigned char __user *) arg,
568 sizeof(reg)))
569 return -EFAULT;
570 parport_frob_control(port, mask, reg);
571 return 0;
572
573 case PPDATADIR:
574 if (copy_from_user(&mode, argp, sizeof(mode)))
575 return -EFAULT;
576 if (mode)
577 port->ops->data_reverse(port);
578 else
579 port->ops->data_forward(port);
580 return 0;
581
582 case PPNEGOT:
583 if (copy_from_user(&mode, argp, sizeof(mode)))
584 return -EFAULT;
585 switch ((ret = parport_negotiate(port, mode))) {
586 case 0: break;
587 case -1: /* handshake failed, peripheral not IEEE 1284 */
588 ret = -EIO;
589 break;
590 case 1: /* handshake succeeded, peripheral rejected mode */
591 ret = -ENXIO;
592 break;
593 }
594 pp_enable_irq(pp);
595 return ret;
596
597 case PPWCTLONIRQ:
598 if (copy_from_user(®, argp, sizeof(reg)))
599 return -EFAULT;
600
601 /* Remember what to set the control lines to, for next
602 * time we get an interrupt. */
603 pp->irqctl = reg;
604 pp->irqresponse = 1;
605 return 0;
606
607 case PPCLRIRQ:
608 ret = atomic_read(&pp->irqc);
609 if (copy_to_user(argp, &ret, sizeof(ret)))
610 return -EFAULT;
611 atomic_sub(ret, &pp->irqc);
612 return 0;
613
614 case PPSETTIME32:
615 if (copy_from_user(time32, argp, sizeof(time32)))
616 return -EFAULT;
617
618 if ((time32[0] < 0) || (time32[1] < 0))
619 return -EINVAL;
620
621 return pp_set_timeout(pp->pdev, time32[0], time32[1]);
622
623 case PPSETTIME64:
624 if (copy_from_user(time64, argp, sizeof(time64)))
625 return -EFAULT;
626
627 if ((time64[0] < 0) || (time64[1] < 0))
628 return -EINVAL;
629
630 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
631 time64[1] >>= 32;
632
633 return pp_set_timeout(pp->pdev, time64[0], time64[1]);
634
635 case PPGETTIME32:
636 jiffies_to_timespec64(pp->pdev->timeout, &ts);
637 time32[0] = ts.tv_sec;
638 time32[1] = ts.tv_nsec / NSEC_PER_USEC;
639
640 if (copy_to_user(argp, time32, sizeof(time32)))
641 return -EFAULT;
642
643 return 0;
644
645 case PPGETTIME64:
646 jiffies_to_timespec64(pp->pdev->timeout, &ts);
647 time64[0] = ts.tv_sec;
648 time64[1] = ts.tv_nsec / NSEC_PER_USEC;
649
650 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
651 time64[1] <<= 32;
652
653 if (copy_to_user(argp, time64, sizeof(time64)))
654 return -EFAULT;
655
656 return 0;
657
658 default:
659 dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd);
660 return -EINVAL;
661 }
662
663 /* Keep the compiler happy */
664 return 0;
665 }
666
pp_ioctl(struct file * file,unsigned int cmd,unsigned long arg)667 static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
668 {
669 long ret;
670
671 mutex_lock(&pp_do_mutex);
672 ret = pp_do_ioctl(file, cmd, arg);
673 mutex_unlock(&pp_do_mutex);
674 return ret;
675 }
676
pp_open(struct inode * inode,struct file * file)677 static int pp_open(struct inode *inode, struct file *file)
678 {
679 unsigned int minor = iminor(inode);
680 struct pp_struct *pp;
681
682 if (minor >= PARPORT_MAX)
683 return -ENXIO;
684
685 pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL);
686 if (!pp)
687 return -ENOMEM;
688
689 pp->state.mode = IEEE1284_MODE_COMPAT;
690 pp->state.phase = init_phase(pp->state.mode);
691 pp->flags = 0;
692 pp->irqresponse = 0;
693 atomic_set(&pp->irqc, 0);
694 init_waitqueue_head(&pp->irq_wait);
695
696 /* Defer the actual device registration until the first claim.
697 * That way, we know whether or not the driver wants to have
698 * exclusive access to the port (PPEXCL).
699 */
700 pp->pdev = NULL;
701 file->private_data = pp;
702
703 return 0;
704 }
705
pp_release(struct inode * inode,struct file * file)706 static int pp_release(struct inode *inode, struct file *file)
707 {
708 unsigned int minor = iminor(inode);
709 struct pp_struct *pp = file->private_data;
710 int compat_negot;
711
712 compat_negot = 0;
713 if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
714 (pp->state.mode != IEEE1284_MODE_COMPAT)) {
715 struct ieee1284_info *info;
716
717 /* parport released, but not in compatibility mode */
718 parport_claim_or_block(pp->pdev);
719 pp->flags |= PP_CLAIMED;
720 info = &pp->pdev->port->ieee1284;
721 pp->saved_state.mode = info->mode;
722 pp->saved_state.phase = info->phase;
723 info->mode = pp->state.mode;
724 info->phase = pp->state.phase;
725 compat_negot = 1;
726 } else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
727 (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
728 compat_negot = 2;
729 }
730 if (compat_negot) {
731 parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT);
732 dev_dbg(&pp->pdev->dev,
733 "negotiated back to compatibility mode because user-space forgot\n");
734 }
735
736 if ((pp->flags & PP_CLAIMED) && pp->pdev) {
737 struct ieee1284_info *info;
738
739 info = &pp->pdev->port->ieee1284;
740 pp->state.mode = info->mode;
741 pp->state.phase = info->phase;
742 info->mode = pp->saved_state.mode;
743 info->phase = pp->saved_state.phase;
744 parport_release(pp->pdev);
745 if (compat_negot != 1) {
746 pr_debug(CHRDEV "%x: released pardevice "
747 "because user-space forgot\n", minor);
748 }
749 }
750
751 if (pp->pdev) {
752 parport_unregister_device(pp->pdev);
753 ida_simple_remove(&ida_index, pp->index);
754 pp->pdev = NULL;
755 pr_debug(CHRDEV "%x: unregistered pardevice\n", minor);
756 }
757
758 kfree(pp);
759
760 return 0;
761 }
762
763 /* No kernel lock held - fine */
pp_poll(struct file * file,poll_table * wait)764 static __poll_t pp_poll(struct file *file, poll_table *wait)
765 {
766 struct pp_struct *pp = file->private_data;
767 __poll_t mask = 0;
768
769 poll_wait(file, &pp->irq_wait, wait);
770 if (atomic_read(&pp->irqc))
771 mask |= EPOLLIN | EPOLLRDNORM;
772
773 return mask;
774 }
775
776 static const struct class ppdev_class = {
777 .name = CHRDEV,
778 };
779
780 static const struct file_operations pp_fops = {
781 .owner = THIS_MODULE,
782 .llseek = no_llseek,
783 .read = pp_read,
784 .write = pp_write,
785 .poll = pp_poll,
786 .unlocked_ioctl = pp_ioctl,
787 .compat_ioctl = compat_ptr_ioctl,
788 .open = pp_open,
789 .release = pp_release,
790 };
791
pp_attach(struct parport * port)792 static void pp_attach(struct parport *port)
793 {
794 struct device *ret;
795
796 if (devices[port->number])
797 return;
798
799 ret = device_create(&ppdev_class, port->dev,
800 MKDEV(PP_MAJOR, port->number), NULL,
801 "parport%d", port->number);
802 if (IS_ERR(ret)) {
803 pr_err("Failed to create device parport%d\n",
804 port->number);
805 return;
806 }
807 devices[port->number] = ret;
808 }
809
pp_detach(struct parport * port)810 static void pp_detach(struct parport *port)
811 {
812 if (!devices[port->number])
813 return;
814
815 device_destroy(&ppdev_class, MKDEV(PP_MAJOR, port->number));
816 devices[port->number] = NULL;
817 }
818
pp_probe(struct pardevice * par_dev)819 static int pp_probe(struct pardevice *par_dev)
820 {
821 struct device_driver *drv = par_dev->dev.driver;
822 int len = strlen(drv->name);
823
824 if (strncmp(par_dev->name, drv->name, len))
825 return -ENODEV;
826
827 return 0;
828 }
829
830 static struct parport_driver pp_driver = {
831 .name = CHRDEV,
832 .probe = pp_probe,
833 .match_port = pp_attach,
834 .detach = pp_detach,
835 .devmodel = true,
836 };
837
ppdev_init(void)838 static int __init ppdev_init(void)
839 {
840 int err = 0;
841
842 if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) {
843 pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR);
844 return -EIO;
845 }
846 err = class_register(&ppdev_class);
847 if (err)
848 goto out_chrdev;
849
850 err = parport_register_driver(&pp_driver);
851 if (err < 0) {
852 pr_warn(CHRDEV ": unable to register with parport\n");
853 goto out_class;
854 }
855
856 pr_info(PP_VERSION "\n");
857 goto out;
858
859 out_class:
860 class_unregister(&ppdev_class);
861 out_chrdev:
862 unregister_chrdev(PP_MAJOR, CHRDEV);
863 out:
864 return err;
865 }
866
ppdev_cleanup(void)867 static void __exit ppdev_cleanup(void)
868 {
869 /* Clean up all parport stuff */
870 parport_unregister_driver(&pp_driver);
871 class_unregister(&ppdev_class);
872 unregister_chrdev(PP_MAJOR, CHRDEV);
873 }
874
875 module_init(ppdev_init);
876 module_exit(ppdev_cleanup);
877
878 MODULE_LICENSE("GPL");
879 MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);
880
