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
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;
300	}
301
302	index = ida_alloc(&ida_index, 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_free(&ida_index, index);
314		goto err;
315	}
316
317	pp->pdev = pdev;
318	pp->index = index;
319	dev_dbg(&pdev->dev, "registered pardevice\n");
320err:
321	kfree(name);
322	return rc;
323}
324
325static 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
336static 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
352static 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, &reg, sizeof(reg)))
524			return -EFAULT;
525		return 0;
526	case PPRDATA:
527		reg = parport_read_data(port);
528		if (copy_to_user(argp, &reg, sizeof(reg)))
529			return -EFAULT;
530		return 0;
531	case PPRCONTROL:
532		reg = parport_read_control(port);
533		if (copy_to_user(argp, &reg, 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(&reg, argp, sizeof(reg)))
553			return -EFAULT;
554		parport_write_control(port, reg);
555		return 0;
556
557	case PPWDATA:
558		if (copy_from_user(&reg, 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(&reg, 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(&reg, 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
667static 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
677static 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
706static 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_free(&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 */
764static __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
776static const struct class ppdev_class = {
777	.name = CHRDEV,
778};
779
780static 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
792static 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
810static 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
819static 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
830static 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
838static 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
859out_class:
860	class_unregister(&ppdev_class);
861out_chrdev:
862	unregister_chrdev(PP_MAJOR, CHRDEV);
863out:
864	return err;
865}
866
867static 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
875module_init(ppdev_init);
876module_exit(ppdev_cleanup);
877
878MODULE_LICENSE("GPL");
879MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);
880