Linux Audio

Check our new training course

Loading...
v4.6
  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};
 88
 
 
 
 
 
 89/* pp_struct.flags bitfields */
 90#define PP_CLAIMED    (1<<0)
 91#define PP_EXCL       (1<<1)
 92
 93/* Other constants */
 94#define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */
 95#define PP_BUFFER_SIZE 1024
 96#define PARDEVICE_MAX 8
 97
 98/* ROUND_UP macro from fs/select.c */
 99#define ROUND_UP(x,y) (((x)+(y)-1)/(y))
100
101static DEFINE_MUTEX(pp_do_mutex);
102
103/* define fixed sized ioctl cmd for y2038 migration */
104#define PPGETTIME32	_IOR(PP_IOCTL, 0x95, s32[2])
105#define PPSETTIME32	_IOW(PP_IOCTL, 0x96, s32[2])
106#define PPGETTIME64	_IOR(PP_IOCTL, 0x95, s64[2])
107#define PPSETTIME64	_IOW(PP_IOCTL, 0x96, s64[2])
108
109static inline void pp_enable_irq(struct pp_struct *pp)
110{
111	struct parport *port = pp->pdev->port;
112
113	port->ops->enable_irq(port);
114}
115
116static ssize_t pp_read(struct file *file, char __user *buf, size_t count,
117		       loff_t *ppos)
118{
119	unsigned int minor = iminor(file_inode(file));
120	struct pp_struct *pp = file->private_data;
121	char *kbuffer;
122	ssize_t bytes_read = 0;
123	struct parport *pport;
124	int mode;
125
126	if (!(pp->flags & PP_CLAIMED)) {
127		/* Don't have the port claimed */
128		pr_debug(CHRDEV "%x: claim the port first\n", minor);
129		return -EINVAL;
130	}
131
132	/* Trivial case. */
133	if (count == 0)
134		return 0;
135
136	kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
137	if (!kbuffer)
138		return -ENOMEM;
139	pport = pp->pdev->port;
140	mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
141
142	parport_set_timeout(pp->pdev,
143			    (file->f_flags & O_NONBLOCK) ?
144			    PARPORT_INACTIVITY_O_NONBLOCK :
145			    pp->default_inactivity);
146
147	while (bytes_read == 0) {
148		ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE);
149
150		if (mode == IEEE1284_MODE_EPP) {
151			/* various specials for EPP mode */
152			int flags = 0;
153			size_t (*fn)(struct parport *, void *, size_t, int);
154
155			if (pp->flags & PP_W91284PIC)
156				flags |= PARPORT_W91284PIC;
157			if (pp->flags & PP_FASTREAD)
158				flags |= PARPORT_EPP_FAST;
159			if (pport->ieee1284.mode & IEEE1284_ADDR)
160				fn = pport->ops->epp_read_addr;
161			else
162				fn = pport->ops->epp_read_data;
163			bytes_read = (*fn)(pport, kbuffer, need, flags);
164		} else {
165			bytes_read = parport_read(pport, kbuffer, need);
166		}
167
168		if (bytes_read != 0)
169			break;
170
171		if (file->f_flags & O_NONBLOCK) {
172			bytes_read = -EAGAIN;
173			break;
174		}
175
176		if (signal_pending(current)) {
177			bytes_read = -ERESTARTSYS;
178			break;
179		}
180
181		cond_resched();
182	}
183
184	parport_set_timeout(pp->pdev, pp->default_inactivity);
185
186	if (bytes_read > 0 && copy_to_user(buf, kbuffer, bytes_read))
187		bytes_read = -EFAULT;
188
189	kfree(kbuffer);
190	pp_enable_irq(pp);
191	return bytes_read;
192}
193
194static ssize_t pp_write(struct file *file, const char __user *buf,
195			size_t count, loff_t *ppos)
196{
197	unsigned int minor = iminor(file_inode(file));
198	struct pp_struct *pp = file->private_data;
199	char *kbuffer;
200	ssize_t bytes_written = 0;
201	ssize_t wrote;
202	int mode;
203	struct parport *pport;
204
205	if (!(pp->flags & PP_CLAIMED)) {
206		/* Don't have the port claimed */
207		pr_debug(CHRDEV "%x: claim the port first\n", minor);
208		return -EINVAL;
209	}
210
211	kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
212	if (!kbuffer)
213		return -ENOMEM;
214
215	pport = pp->pdev->port;
216	mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
217
218	parport_set_timeout(pp->pdev,
219			    (file->f_flags & O_NONBLOCK) ?
220			    PARPORT_INACTIVITY_O_NONBLOCK :
221			    pp->default_inactivity);
222
223	while (bytes_written < count) {
224		ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE);
225
226		if (copy_from_user(kbuffer, buf + bytes_written, n)) {
227			bytes_written = -EFAULT;
228			break;
229		}
230
231		if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) {
232			/* do a fast EPP write */
233			if (pport->ieee1284.mode & IEEE1284_ADDR) {
234				wrote = pport->ops->epp_write_addr(pport,
235					kbuffer, n, PARPORT_EPP_FAST);
236			} else {
237				wrote = pport->ops->epp_write_data(pport,
238					kbuffer, n, PARPORT_EPP_FAST);
239			}
240		} else {
241			wrote = parport_write(pp->pdev->port, kbuffer, n);
242		}
243
244		if (wrote <= 0) {
245			if (!bytes_written)
246				bytes_written = wrote;
247			break;
248		}
249
250		bytes_written += wrote;
251
252		if (file->f_flags & O_NONBLOCK) {
253			if (!bytes_written)
254				bytes_written = -EAGAIN;
255			break;
256		}
257
258		if (signal_pending(current))
259			break;
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	dev_dbg(&pdev->dev, "registered pardevice\n");
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_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec)
330{
331	long to_jiffies;
332
333	if ((tv_sec < 0) || (tv_usec < 0))
334		return -EINVAL;
335
336	to_jiffies = usecs_to_jiffies(tv_usec);
337	to_jiffies += tv_sec * HZ;
338	if (to_jiffies <= 0)
339		return -EINVAL;
340
341	pdev->timeout = to_jiffies;
342	return 0;
343}
344
345static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
346{
347	unsigned int minor = iminor(file_inode(file));
348	struct pp_struct *pp = file->private_data;
349	struct parport *port;
350	void __user *argp = (void __user *)arg;
351
352	/* First handle the cases that don't take arguments. */
353	switch (cmd) {
354	case PPCLAIM:
355	    {
356		struct ieee1284_info *info;
357		int ret;
358
359		if (pp->flags & PP_CLAIMED) {
360			dev_dbg(&pp->pdev->dev, "you've already got it!\n");
361			return -EINVAL;
362		}
363
364		/* Deferred device registration. */
365		if (!pp->pdev) {
366			int err = register_device(minor, pp);
367
368			if (err)
369				return err;
370		}
371
372		ret = parport_claim_or_block(pp->pdev);
373		if (ret < 0)
374			return ret;
375
376		pp->flags |= PP_CLAIMED;
377
378		/* For interrupt-reporting to work, we need to be
379		 * informed of each interrupt. */
380		pp_enable_irq(pp);
381
382		/* We may need to fix up the state machine. */
383		info = &pp->pdev->port->ieee1284;
384		pp->saved_state.mode = info->mode;
385		pp->saved_state.phase = info->phase;
386		info->mode = pp->state.mode;
387		info->phase = pp->state.phase;
388		pp->default_inactivity = parport_set_timeout(pp->pdev, 0);
389		parport_set_timeout(pp->pdev, pp->default_inactivity);
390
391		return 0;
392	    }
393	case PPEXCL:
394		if (pp->pdev) {
395			dev_dbg(&pp->pdev->dev,
396				"too late for PPEXCL; already registered\n");
397			if (pp->flags & PP_EXCL)
398				/* But it's not really an error. */
399				return 0;
400			/* There's no chance of making the driver happy. */
401			return -EINVAL;
402		}
403
404		/* Just remember to register the device exclusively
405		 * when we finally do the registration. */
406		pp->flags |= PP_EXCL;
407		return 0;
408	case PPSETMODE:
409	    {
410		int mode;
411
412		if (copy_from_user(&mode, argp, sizeof(mode)))
413			return -EFAULT;
414		/* FIXME: validate mode */
415		pp->state.mode = mode;
416		pp->state.phase = init_phase(mode);
417
418		if (pp->flags & PP_CLAIMED) {
419			pp->pdev->port->ieee1284.mode = mode;
420			pp->pdev->port->ieee1284.phase = pp->state.phase;
421		}
422
423		return 0;
424	    }
425	case PPGETMODE:
426	    {
427		int mode;
428
429		if (pp->flags & PP_CLAIMED)
430			mode = pp->pdev->port->ieee1284.mode;
431		else
432			mode = pp->state.mode;
433
434		if (copy_to_user(argp, &mode, sizeof(mode)))
435			return -EFAULT;
436		return 0;
437	    }
438	case PPSETPHASE:
439	    {
440		int phase;
441
442		if (copy_from_user(&phase, argp, sizeof(phase)))
443			return -EFAULT;
444
445		/* FIXME: validate phase */
446		pp->state.phase = phase;
447
448		if (pp->flags & PP_CLAIMED)
449			pp->pdev->port->ieee1284.phase = phase;
450
451		return 0;
452	    }
453	case PPGETPHASE:
454	    {
455		int phase;
456
457		if (pp->flags & PP_CLAIMED)
458			phase = pp->pdev->port->ieee1284.phase;
459		else
460			phase = pp->state.phase;
461		if (copy_to_user(argp, &phase, sizeof(phase)))
462			return -EFAULT;
463		return 0;
464	    }
465	case PPGETMODES:
466	    {
467		unsigned int modes;
468
469		port = parport_find_number(minor);
470		if (!port)
471			return -ENODEV;
472
473		modes = port->modes;
474		parport_put_port(port);
475		if (copy_to_user(argp, &modes, sizeof(modes)))
476			return -EFAULT;
477		return 0;
478	    }
479	case PPSETFLAGS:
480	    {
481		int uflags;
482
483		if (copy_from_user(&uflags, argp, sizeof(uflags)))
484			return -EFAULT;
485		pp->flags &= ~PP_FLAGMASK;
486		pp->flags |= (uflags & PP_FLAGMASK);
487		return 0;
488	    }
489	case PPGETFLAGS:
490	    {
491		int uflags;
492
493		uflags = pp->flags & PP_FLAGMASK;
494		if (copy_to_user(argp, &uflags, sizeof(uflags)))
495			return -EFAULT;
496		return 0;
497	    }
498	}	/* end switch() */
499
500	/* Everything else requires the port to be claimed, so check
501	 * that now. */
502	if ((pp->flags & PP_CLAIMED) == 0) {
503		pr_debug(CHRDEV "%x: claim the port first\n", minor);
504		return -EINVAL;
505	}
506
507	port = pp->pdev->port;
508	switch (cmd) {
509		struct ieee1284_info *info;
510		unsigned char reg;
511		unsigned char mask;
512		int mode;
513		s32 time32[2];
514		s64 time64[2];
515		struct timespec64 ts;
516		int ret;
517
518	case PPRSTATUS:
519		reg = parport_read_status(port);
520		if (copy_to_user(argp, &reg, sizeof(reg)))
521			return -EFAULT;
522		return 0;
523	case PPRDATA:
524		reg = parport_read_data(port);
525		if (copy_to_user(argp, &reg, sizeof(reg)))
526			return -EFAULT;
527		return 0;
528	case PPRCONTROL:
529		reg = parport_read_control(port);
530		if (copy_to_user(argp, &reg, sizeof(reg)))
531			return -EFAULT;
532		return 0;
533	case PPYIELD:
534		parport_yield_blocking(pp->pdev);
535		return 0;
536
537	case PPRELEASE:
538		/* Save the state machine's state. */
539		info = &pp->pdev->port->ieee1284;
540		pp->state.mode = info->mode;
541		pp->state.phase = info->phase;
542		info->mode = pp->saved_state.mode;
543		info->phase = pp->saved_state.phase;
544		parport_release(pp->pdev);
545		pp->flags &= ~PP_CLAIMED;
546		return 0;
547
548	case PPWCONTROL:
549		if (copy_from_user(&reg, argp, sizeof(reg)))
550			return -EFAULT;
551		parport_write_control(port, reg);
552		return 0;
553
554	case PPWDATA:
555		if (copy_from_user(&reg, argp, sizeof(reg)))
556			return -EFAULT;
557		parport_write_data(port, reg);
558		return 0;
559
560	case PPFCONTROL:
561		if (copy_from_user(&mask, argp,
562				   sizeof(mask)))
563			return -EFAULT;
564		if (copy_from_user(&reg, 1 + (unsigned char __user *) arg,
565				   sizeof(reg)))
566			return -EFAULT;
567		parport_frob_control(port, mask, reg);
568		return 0;
569
570	case PPDATADIR:
571		if (copy_from_user(&mode, argp, sizeof(mode)))
572			return -EFAULT;
573		if (mode)
574			port->ops->data_reverse(port);
575		else
576			port->ops->data_forward(port);
577		return 0;
578
579	case PPNEGOT:
580		if (copy_from_user(&mode, argp, sizeof(mode)))
581			return -EFAULT;
582		switch ((ret = parport_negotiate(port, mode))) {
583		case 0: break;
584		case -1: /* handshake failed, peripheral not IEEE 1284 */
585			ret = -EIO;
586			break;
587		case 1:  /* handshake succeeded, peripheral rejected mode */
588			ret = -ENXIO;
589			break;
590		}
591		pp_enable_irq(pp);
592		return ret;
593
594	case PPWCTLONIRQ:
595		if (copy_from_user(&reg, argp, sizeof(reg)))
596			return -EFAULT;
597
598		/* Remember what to set the control lines to, for next
599		 * time we get an interrupt. */
600		pp->irqctl = reg;
601		pp->irqresponse = 1;
602		return 0;
603
604	case PPCLRIRQ:
605		ret = atomic_read(&pp->irqc);
606		if (copy_to_user(argp, &ret, sizeof(ret)))
607			return -EFAULT;
608		atomic_sub(ret, &pp->irqc);
609		return 0;
610
611	case PPSETTIME32:
612		if (copy_from_user(time32, argp, sizeof(time32)))
613			return -EFAULT;
614
615		return pp_set_timeout(pp->pdev, time32[0], time32[1]);
616
617	case PPSETTIME64:
618		if (copy_from_user(time64, argp, sizeof(time64)))
619			return -EFAULT;
620
621		return pp_set_timeout(pp->pdev, time64[0], time64[1]);
622
623	case PPGETTIME32:
624		jiffies_to_timespec64(pp->pdev->timeout, &ts);
625		time32[0] = ts.tv_sec;
626		time32[1] = ts.tv_nsec / NSEC_PER_USEC;
627		if ((time32[0] < 0) || (time32[1] < 0))
628			return -EINVAL;
629
630		if (copy_to_user(argp, time32, sizeof(time32)))
631			return -EFAULT;
632
633		return 0;
634
635	case PPGETTIME64:
636		jiffies_to_timespec64(pp->pdev->timeout, &ts);
637		time64[0] = ts.tv_sec;
638		time64[1] = ts.tv_nsec / NSEC_PER_USEC;
639		if ((time64[0] < 0) || (time64[1] < 0))
640			return -EINVAL;
641
642		if (copy_to_user(argp, time64, sizeof(time64)))
643			return -EFAULT;
644
645		return 0;
646
647	default:
648		dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd);
649		return -EINVAL;
650	}
651
652	/* Keep the compiler happy */
653	return 0;
654}
655
656static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
657{
658	long ret;
659
660	mutex_lock(&pp_do_mutex);
661	ret = pp_do_ioctl(file, cmd, arg);
662	mutex_unlock(&pp_do_mutex);
663	return ret;
664}
665
666#ifdef CONFIG_COMPAT
667static long pp_compat_ioctl(struct file *file, unsigned int cmd,
668			    unsigned long arg)
669{
670	return pp_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
671}
672#endif
673
674static int pp_open(struct inode *inode, struct file *file)
675{
676	unsigned int minor = iminor(inode);
677	struct pp_struct *pp;
678
679	if (minor >= PARPORT_MAX)
680		return -ENXIO;
681
682	pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL);
683	if (!pp)
684		return -ENOMEM;
685
686	pp->state.mode = IEEE1284_MODE_COMPAT;
687	pp->state.phase = init_phase(pp->state.mode);
688	pp->flags = 0;
689	pp->irqresponse = 0;
690	atomic_set(&pp->irqc, 0);
691	init_waitqueue_head(&pp->irq_wait);
692
693	/* Defer the actual device registration until the first claim.
694	 * That way, we know whether or not the driver wants to have
695	 * exclusive access to the port (PPEXCL).
696	 */
697	pp->pdev = NULL;
698	file->private_data = pp;
699
700	return 0;
701}
702
703static int pp_release(struct inode *inode, struct file *file)
704{
705	unsigned int minor = iminor(inode);
706	struct pp_struct *pp = file->private_data;
707	int compat_negot;
708
709	compat_negot = 0;
710	if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
711	    (pp->state.mode != IEEE1284_MODE_COMPAT)) {
712		struct ieee1284_info *info;
713
714		/* parport released, but not in compatibility mode */
715		parport_claim_or_block(pp->pdev);
716		pp->flags |= PP_CLAIMED;
717		info = &pp->pdev->port->ieee1284;
718		pp->saved_state.mode = info->mode;
719		pp->saved_state.phase = info->phase;
720		info->mode = pp->state.mode;
721		info->phase = pp->state.phase;
722		compat_negot = 1;
723	} else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
724	    (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
725		compat_negot = 2;
726	}
727	if (compat_negot) {
728		parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT);
729		dev_dbg(&pp->pdev->dev,
730			"negotiated back to compatibility mode because user-space forgot\n");
731	}
732
733	if (pp->flags & PP_CLAIMED) {
734		struct ieee1284_info *info;
735
736		info = &pp->pdev->port->ieee1284;
737		pp->state.mode = info->mode;
738		pp->state.phase = info->phase;
739		info->mode = pp->saved_state.mode;
740		info->phase = pp->saved_state.phase;
741		parport_release(pp->pdev);
742		if (compat_negot != 1) {
743			pr_debug(CHRDEV "%x: released pardevice "
744				"because user-space forgot\n", minor);
745		}
746	}
747
748	if (pp->pdev) {
749		const char *name = pp->pdev->name;
750
751		parport_unregister_device(pp->pdev);
752		kfree(name);
753		pp->pdev = NULL;
754		pr_debug(CHRDEV "%x: unregistered pardevice\n", minor);
755	}
756
757	kfree(pp);
758
759	return 0;
760}
761
762/* No kernel lock held - fine */
763static unsigned int pp_poll(struct file *file, poll_table *wait)
764{
765	struct pp_struct *pp = file->private_data;
766	unsigned int mask = 0;
767
768	poll_wait(file, &pp->irq_wait, wait);
769	if (atomic_read(&pp->irqc))
770		mask |= POLLIN | POLLRDNORM;
771
772	return mask;
773}
774
775static struct class *ppdev_class;
776
777static const struct file_operations pp_fops = {
778	.owner		= THIS_MODULE,
779	.llseek		= no_llseek,
780	.read		= pp_read,
781	.write		= pp_write,
782	.poll		= pp_poll,
783	.unlocked_ioctl	= pp_ioctl,
784#ifdef CONFIG_COMPAT
785	.compat_ioctl   = pp_compat_ioctl,
786#endif
787	.open		= pp_open,
788	.release	= pp_release,
789};
790
791static void pp_attach(struct parport *port)
792{
793	device_create(ppdev_class, port->dev, MKDEV(PP_MAJOR, port->number),
794		      NULL, "parport%d", port->number);
 
 
 
 
 
 
 
 
 
 
 
 
795}
796
797static void pp_detach(struct parport *port)
798{
 
 
 
799	device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number));
 
 
 
 
 
 
 
 
 
 
 
 
800}
801
802static struct parport_driver pp_driver = {
803	.name		= CHRDEV,
804	.attach		= pp_attach,
 
805	.detach		= pp_detach,
 
806};
807
808static int __init ppdev_init(void)
809{
810	int err = 0;
811
812	if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) {
813		printk(KERN_WARNING CHRDEV ": unable to get major %d\n",
814		       PP_MAJOR);
815		return -EIO;
816	}
817	ppdev_class = class_create(THIS_MODULE, CHRDEV);
818	if (IS_ERR(ppdev_class)) {
819		err = PTR_ERR(ppdev_class);
820		goto out_chrdev;
821	}
822	err = parport_register_driver(&pp_driver);
823	if (err < 0) {
824		printk(KERN_WARNING CHRDEV ": unable to register with parport\n");
825		goto out_class;
826	}
827
828	printk(KERN_INFO PP_VERSION "\n");
829	goto out;
830
831out_class:
832	class_destroy(ppdev_class);
833out_chrdev:
834	unregister_chrdev(PP_MAJOR, CHRDEV);
835out:
836	return err;
837}
838
839static void __exit ppdev_cleanup(void)
840{
841	/* Clean up all parport stuff */
842	parport_unregister_driver(&pp_driver);
843	class_destroy(ppdev_class);
844	unregister_chrdev(PP_MAJOR, CHRDEV);
845}
846
847module_init(ppdev_init);
848module_exit(ppdev_cleanup);
849
850MODULE_LICENSE("GPL");
851MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);
v4.17
  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/signal.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
 
 
 
104static DEFINE_MUTEX(pp_do_mutex);
105
106/* define fixed sized ioctl cmd for y2038 migration */
107#define PPGETTIME32	_IOR(PP_IOCTL, 0x95, s32[2])
108#define PPSETTIME32	_IOW(PP_IOCTL, 0x96, s32[2])
109#define PPGETTIME64	_IOR(PP_IOCTL, 0x95, s64[2])
110#define PPSETTIME64	_IOW(PP_IOCTL, 0x96, s64[2])
111
112static inline void pp_enable_irq(struct pp_struct *pp)
113{
114	struct parport *port = pp->pdev->port;
115
116	port->ops->enable_irq(port);
117}
118
119static ssize_t pp_read(struct file *file, char __user *buf, size_t count,
120		       loff_t *ppos)
121{
122	unsigned int minor = iminor(file_inode(file));
123	struct pp_struct *pp = file->private_data;
124	char *kbuffer;
125	ssize_t bytes_read = 0;
126	struct parport *pport;
127	int mode;
128
129	if (!(pp->flags & PP_CLAIMED)) {
130		/* Don't have the port claimed */
131		pr_debug(CHRDEV "%x: claim the port first\n", minor);
132		return -EINVAL;
133	}
134
135	/* Trivial case. */
136	if (count == 0)
137		return 0;
138
139	kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
140	if (!kbuffer)
141		return -ENOMEM;
142	pport = pp->pdev->port;
143	mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
144
145	parport_set_timeout(pp->pdev,
146			    (file->f_flags & O_NONBLOCK) ?
147			    PARPORT_INACTIVITY_O_NONBLOCK :
148			    pp->default_inactivity);
149
150	while (bytes_read == 0) {
151		ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE);
152
153		if (mode == IEEE1284_MODE_EPP) {
154			/* various specials for EPP mode */
155			int flags = 0;
156			size_t (*fn)(struct parport *, void *, size_t, int);
157
158			if (pp->flags & PP_W91284PIC)
159				flags |= PARPORT_W91284PIC;
160			if (pp->flags & PP_FASTREAD)
161				flags |= PARPORT_EPP_FAST;
162			if (pport->ieee1284.mode & IEEE1284_ADDR)
163				fn = pport->ops->epp_read_addr;
164			else
165				fn = pport->ops->epp_read_data;
166			bytes_read = (*fn)(pport, kbuffer, need, flags);
167		} else {
168			bytes_read = parport_read(pport, kbuffer, need);
169		}
170
171		if (bytes_read != 0)
172			break;
173
174		if (file->f_flags & O_NONBLOCK) {
175			bytes_read = -EAGAIN;
176			break;
177		}
178
179		if (signal_pending(current)) {
180			bytes_read = -ERESTARTSYS;
181			break;
182		}
183
184		cond_resched();
185	}
186
187	parport_set_timeout(pp->pdev, pp->default_inactivity);
188
189	if (bytes_read > 0 && copy_to_user(buf, kbuffer, bytes_read))
190		bytes_read = -EFAULT;
191
192	kfree(kbuffer);
193	pp_enable_irq(pp);
194	return bytes_read;
195}
196
197static ssize_t pp_write(struct file *file, const char __user *buf,
198			size_t count, loff_t *ppos)
199{
200	unsigned int minor = iminor(file_inode(file));
201	struct pp_struct *pp = file->private_data;
202	char *kbuffer;
203	ssize_t bytes_written = 0;
204	ssize_t wrote;
205	int mode;
206	struct parport *pport;
207
208	if (!(pp->flags & PP_CLAIMED)) {
209		/* Don't have the port claimed */
210		pr_debug(CHRDEV "%x: claim the port first\n", minor);
211		return -EINVAL;
212	}
213
214	kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
215	if (!kbuffer)
216		return -ENOMEM;
217
218	pport = pp->pdev->port;
219	mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
220
221	parport_set_timeout(pp->pdev,
222			    (file->f_flags & O_NONBLOCK) ?
223			    PARPORT_INACTIVITY_O_NONBLOCK :
224			    pp->default_inactivity);
225
226	while (bytes_written < count) {
227		ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE);
228
229		if (copy_from_user(kbuffer, buf + bytes_written, n)) {
230			bytes_written = -EFAULT;
231			break;
232		}
233
234		if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) {
235			/* do a fast EPP write */
236			if (pport->ieee1284.mode & IEEE1284_ADDR) {
237				wrote = pport->ops->epp_write_addr(pport,
238					kbuffer, n, PARPORT_EPP_FAST);
239			} else {
240				wrote = pport->ops->epp_write_data(pport,
241					kbuffer, n, PARPORT_EPP_FAST);
242			}
243		} else {
244			wrote = parport_write(pp->pdev->port, kbuffer, n);
245		}
246
247		if (wrote <= 0) {
248			if (!bytes_written)
249				bytes_written = wrote;
250			break;
251		}
252
253		bytes_written += wrote;
254
255		if (file->f_flags & O_NONBLOCK) {
256			if (!bytes_written)
257				bytes_written = -EAGAIN;
258			break;
259		}
260
261		if (signal_pending(current))
262			break;
263
264		cond_resched();
265	}
266
267	parport_set_timeout(pp->pdev, pp->default_inactivity);
268
269	kfree(kbuffer);
270	pp_enable_irq(pp);
271	return bytes_written;
272}
273
274static void pp_irq(void *private)
275{
276	struct pp_struct *pp = private;
277
278	if (pp->irqresponse) {
279		parport_write_control(pp->pdev->port, pp->irqctl);
280		pp->irqresponse = 0;
281	}
282
283	atomic_inc(&pp->irqc);
284	wake_up_interruptible(&pp->irq_wait);
285}
286
287static int register_device(int minor, struct pp_struct *pp)
288{
289	struct parport *port;
290	struct pardevice *pdev = NULL;
291	char *name;
292	struct pardev_cb ppdev_cb;
293	int rc = 0, index;
294
295	name = kasprintf(GFP_KERNEL, CHRDEV "%x", minor);
296	if (name == NULL)
297		return -ENOMEM;
298
299	port = parport_find_number(minor);
300	if (!port) {
301		pr_warn("%s: no associated port!\n", name);
302		rc = -ENXIO;
303		goto err;
304	}
305
306	index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL);
307	memset(&ppdev_cb, 0, sizeof(ppdev_cb));
308	ppdev_cb.irq_func = pp_irq;
309	ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0;
310	ppdev_cb.private = pp;
311	pdev = parport_register_dev_model(port, name, &ppdev_cb, index);
312	parport_put_port(port);
313
314	if (!pdev) {
315		pr_warn("%s: failed to register device!\n", name);
316		rc = -ENXIO;
317		ida_simple_remove(&ida_index, index);
318		goto err;
319	}
320
321	pp->pdev = pdev;
322	pp->index = index;
323	dev_dbg(&pdev->dev, "registered pardevice\n");
324err:
325	kfree(name);
326	return rc;
327}
328
329static enum ieee1284_phase init_phase(int mode)
330{
331	switch (mode & ~(IEEE1284_DEVICEID
332			 | IEEE1284_ADDR)) {
333	case IEEE1284_MODE_NIBBLE:
334	case IEEE1284_MODE_BYTE:
335		return IEEE1284_PH_REV_IDLE;
336	}
337	return IEEE1284_PH_FWD_IDLE;
338}
339
340static int pp_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec)
341{
342	long to_jiffies;
343
344	if ((tv_sec < 0) || (tv_usec < 0))
345		return -EINVAL;
346
347	to_jiffies = usecs_to_jiffies(tv_usec);
348	to_jiffies += tv_sec * HZ;
349	if (to_jiffies <= 0)
350		return -EINVAL;
351
352	pdev->timeout = to_jiffies;
353	return 0;
354}
355
356static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
357{
358	unsigned int minor = iminor(file_inode(file));
359	struct pp_struct *pp = file->private_data;
360	struct parport *port;
361	void __user *argp = (void __user *)arg;
362
363	/* First handle the cases that don't take arguments. */
364	switch (cmd) {
365	case PPCLAIM:
366	    {
367		struct ieee1284_info *info;
368		int ret;
369
370		if (pp->flags & PP_CLAIMED) {
371			dev_dbg(&pp->pdev->dev, "you've already got it!\n");
372			return -EINVAL;
373		}
374
375		/* Deferred device registration. */
376		if (!pp->pdev) {
377			int err = register_device(minor, pp);
378
379			if (err)
380				return err;
381		}
382
383		ret = parport_claim_or_block(pp->pdev);
384		if (ret < 0)
385			return ret;
386
387		pp->flags |= PP_CLAIMED;
388
389		/* For interrupt-reporting to work, we need to be
390		 * informed of each interrupt. */
391		pp_enable_irq(pp);
392
393		/* We may need to fix up the state machine. */
394		info = &pp->pdev->port->ieee1284;
395		pp->saved_state.mode = info->mode;
396		pp->saved_state.phase = info->phase;
397		info->mode = pp->state.mode;
398		info->phase = pp->state.phase;
399		pp->default_inactivity = parport_set_timeout(pp->pdev, 0);
400		parport_set_timeout(pp->pdev, pp->default_inactivity);
401
402		return 0;
403	    }
404	case PPEXCL:
405		if (pp->pdev) {
406			dev_dbg(&pp->pdev->dev,
407				"too late for PPEXCL; already registered\n");
408			if (pp->flags & PP_EXCL)
409				/* But it's not really an error. */
410				return 0;
411			/* There's no chance of making the driver happy. */
412			return -EINVAL;
413		}
414
415		/* Just remember to register the device exclusively
416		 * when we finally do the registration. */
417		pp->flags |= PP_EXCL;
418		return 0;
419	case PPSETMODE:
420	    {
421		int mode;
422
423		if (copy_from_user(&mode, argp, sizeof(mode)))
424			return -EFAULT;
425		/* FIXME: validate mode */
426		pp->state.mode = mode;
427		pp->state.phase = init_phase(mode);
428
429		if (pp->flags & PP_CLAIMED) {
430			pp->pdev->port->ieee1284.mode = mode;
431			pp->pdev->port->ieee1284.phase = pp->state.phase;
432		}
433
434		return 0;
435	    }
436	case PPGETMODE:
437	    {
438		int mode;
439
440		if (pp->flags & PP_CLAIMED)
441			mode = pp->pdev->port->ieee1284.mode;
442		else
443			mode = pp->state.mode;
444
445		if (copy_to_user(argp, &mode, sizeof(mode)))
446			return -EFAULT;
447		return 0;
448	    }
449	case PPSETPHASE:
450	    {
451		int phase;
452
453		if (copy_from_user(&phase, argp, sizeof(phase)))
454			return -EFAULT;
455
456		/* FIXME: validate phase */
457		pp->state.phase = phase;
458
459		if (pp->flags & PP_CLAIMED)
460			pp->pdev->port->ieee1284.phase = phase;
461
462		return 0;
463	    }
464	case PPGETPHASE:
465	    {
466		int phase;
467
468		if (pp->flags & PP_CLAIMED)
469			phase = pp->pdev->port->ieee1284.phase;
470		else
471			phase = pp->state.phase;
472		if (copy_to_user(argp, &phase, sizeof(phase)))
473			return -EFAULT;
474		return 0;
475	    }
476	case PPGETMODES:
477	    {
478		unsigned int modes;
479
480		port = parport_find_number(minor);
481		if (!port)
482			return -ENODEV;
483
484		modes = port->modes;
485		parport_put_port(port);
486		if (copy_to_user(argp, &modes, sizeof(modes)))
487			return -EFAULT;
488		return 0;
489	    }
490	case PPSETFLAGS:
491	    {
492		int uflags;
493
494		if (copy_from_user(&uflags, argp, sizeof(uflags)))
495			return -EFAULT;
496		pp->flags &= ~PP_FLAGMASK;
497		pp->flags |= (uflags & PP_FLAGMASK);
498		return 0;
499	    }
500	case PPGETFLAGS:
501	    {
502		int uflags;
503
504		uflags = pp->flags & PP_FLAGMASK;
505		if (copy_to_user(argp, &uflags, sizeof(uflags)))
506			return -EFAULT;
507		return 0;
508	    }
509	}	/* end switch() */
510
511	/* Everything else requires the port to be claimed, so check
512	 * that now. */
513	if ((pp->flags & PP_CLAIMED) == 0) {
514		pr_debug(CHRDEV "%x: claim the port first\n", minor);
515		return -EINVAL;
516	}
517
518	port = pp->pdev->port;
519	switch (cmd) {
520		struct ieee1284_info *info;
521		unsigned char reg;
522		unsigned char mask;
523		int mode;
524		s32 time32[2];
525		s64 time64[2];
526		struct timespec64 ts;
527		int ret;
528
529	case PPRSTATUS:
530		reg = parport_read_status(port);
531		if (copy_to_user(argp, &reg, sizeof(reg)))
532			return -EFAULT;
533		return 0;
534	case PPRDATA:
535		reg = parport_read_data(port);
536		if (copy_to_user(argp, &reg, sizeof(reg)))
537			return -EFAULT;
538		return 0;
539	case PPRCONTROL:
540		reg = parport_read_control(port);
541		if (copy_to_user(argp, &reg, sizeof(reg)))
542			return -EFAULT;
543		return 0;
544	case PPYIELD:
545		parport_yield_blocking(pp->pdev);
546		return 0;
547
548	case PPRELEASE:
549		/* Save the state machine's state. */
550		info = &pp->pdev->port->ieee1284;
551		pp->state.mode = info->mode;
552		pp->state.phase = info->phase;
553		info->mode = pp->saved_state.mode;
554		info->phase = pp->saved_state.phase;
555		parport_release(pp->pdev);
556		pp->flags &= ~PP_CLAIMED;
557		return 0;
558
559	case PPWCONTROL:
560		if (copy_from_user(&reg, argp, sizeof(reg)))
561			return -EFAULT;
562		parport_write_control(port, reg);
563		return 0;
564
565	case PPWDATA:
566		if (copy_from_user(&reg, argp, sizeof(reg)))
567			return -EFAULT;
568		parport_write_data(port, reg);
569		return 0;
570
571	case PPFCONTROL:
572		if (copy_from_user(&mask, argp,
573				   sizeof(mask)))
574			return -EFAULT;
575		if (copy_from_user(&reg, 1 + (unsigned char __user *) arg,
576				   sizeof(reg)))
577			return -EFAULT;
578		parport_frob_control(port, mask, reg);
579		return 0;
580
581	case PPDATADIR:
582		if (copy_from_user(&mode, argp, sizeof(mode)))
583			return -EFAULT;
584		if (mode)
585			port->ops->data_reverse(port);
586		else
587			port->ops->data_forward(port);
588		return 0;
589
590	case PPNEGOT:
591		if (copy_from_user(&mode, argp, sizeof(mode)))
592			return -EFAULT;
593		switch ((ret = parport_negotiate(port, mode))) {
594		case 0: break;
595		case -1: /* handshake failed, peripheral not IEEE 1284 */
596			ret = -EIO;
597			break;
598		case 1:  /* handshake succeeded, peripheral rejected mode */
599			ret = -ENXIO;
600			break;
601		}
602		pp_enable_irq(pp);
603		return ret;
604
605	case PPWCTLONIRQ:
606		if (copy_from_user(&reg, argp, sizeof(reg)))
607			return -EFAULT;
608
609		/* Remember what to set the control lines to, for next
610		 * time we get an interrupt. */
611		pp->irqctl = reg;
612		pp->irqresponse = 1;
613		return 0;
614
615	case PPCLRIRQ:
616		ret = atomic_read(&pp->irqc);
617		if (copy_to_user(argp, &ret, sizeof(ret)))
618			return -EFAULT;
619		atomic_sub(ret, &pp->irqc);
620		return 0;
621
622	case PPSETTIME32:
623		if (copy_from_user(time32, argp, sizeof(time32)))
624			return -EFAULT;
625
626		return pp_set_timeout(pp->pdev, time32[0], time32[1]);
627
628	case PPSETTIME64:
629		if (copy_from_user(time64, argp, sizeof(time64)))
630			return -EFAULT;
631
632		return pp_set_timeout(pp->pdev, time64[0], time64[1]);
633
634	case PPGETTIME32:
635		jiffies_to_timespec64(pp->pdev->timeout, &ts);
636		time32[0] = ts.tv_sec;
637		time32[1] = ts.tv_nsec / NSEC_PER_USEC;
638		if ((time32[0] < 0) || (time32[1] < 0))
639			return -EINVAL;
640
641		if (copy_to_user(argp, time32, sizeof(time32)))
642			return -EFAULT;
643
644		return 0;
645
646	case PPGETTIME64:
647		jiffies_to_timespec64(pp->pdev->timeout, &ts);
648		time64[0] = ts.tv_sec;
649		time64[1] = ts.tv_nsec / NSEC_PER_USEC;
650		if ((time64[0] < 0) || (time64[1] < 0))
651			return -EINVAL;
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
677#ifdef CONFIG_COMPAT
678static long pp_compat_ioctl(struct file *file, unsigned int cmd,
679			    unsigned long arg)
680{
681	return pp_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
682}
683#endif
684
685static int pp_open(struct inode *inode, struct file *file)
686{
687	unsigned int minor = iminor(inode);
688	struct pp_struct *pp;
689
690	if (minor >= PARPORT_MAX)
691		return -ENXIO;
692
693	pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL);
694	if (!pp)
695		return -ENOMEM;
696
697	pp->state.mode = IEEE1284_MODE_COMPAT;
698	pp->state.phase = init_phase(pp->state.mode);
699	pp->flags = 0;
700	pp->irqresponse = 0;
701	atomic_set(&pp->irqc, 0);
702	init_waitqueue_head(&pp->irq_wait);
703
704	/* Defer the actual device registration until the first claim.
705	 * That way, we know whether or not the driver wants to have
706	 * exclusive access to the port (PPEXCL).
707	 */
708	pp->pdev = NULL;
709	file->private_data = pp;
710
711	return 0;
712}
713
714static int pp_release(struct inode *inode, struct file *file)
715{
716	unsigned int minor = iminor(inode);
717	struct pp_struct *pp = file->private_data;
718	int compat_negot;
719
720	compat_negot = 0;
721	if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
722	    (pp->state.mode != IEEE1284_MODE_COMPAT)) {
723		struct ieee1284_info *info;
724
725		/* parport released, but not in compatibility mode */
726		parport_claim_or_block(pp->pdev);
727		pp->flags |= PP_CLAIMED;
728		info = &pp->pdev->port->ieee1284;
729		pp->saved_state.mode = info->mode;
730		pp->saved_state.phase = info->phase;
731		info->mode = pp->state.mode;
732		info->phase = pp->state.phase;
733		compat_negot = 1;
734	} else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
735	    (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
736		compat_negot = 2;
737	}
738	if (compat_negot) {
739		parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT);
740		dev_dbg(&pp->pdev->dev,
741			"negotiated back to compatibility mode because user-space forgot\n");
742	}
743
744	if (pp->flags & PP_CLAIMED) {
745		struct ieee1284_info *info;
746
747		info = &pp->pdev->port->ieee1284;
748		pp->state.mode = info->mode;
749		pp->state.phase = info->phase;
750		info->mode = pp->saved_state.mode;
751		info->phase = pp->saved_state.phase;
752		parport_release(pp->pdev);
753		if (compat_negot != 1) {
754			pr_debug(CHRDEV "%x: released pardevice "
755				"because user-space forgot\n", minor);
756		}
757	}
758
759	if (pp->pdev) {
 
 
760		parport_unregister_device(pp->pdev);
761		ida_simple_remove(&ida_index, pp->index);
762		pp->pdev = NULL;
763		pr_debug(CHRDEV "%x: unregistered pardevice\n", minor);
764	}
765
766	kfree(pp);
767
768	return 0;
769}
770
771/* No kernel lock held - fine */
772static __poll_t pp_poll(struct file *file, poll_table *wait)
773{
774	struct pp_struct *pp = file->private_data;
775	__poll_t mask = 0;
776
777	poll_wait(file, &pp->irq_wait, wait);
778	if (atomic_read(&pp->irqc))
779		mask |= EPOLLIN | EPOLLRDNORM;
780
781	return mask;
782}
783
784static struct class *ppdev_class;
785
786static const struct file_operations pp_fops = {
787	.owner		= THIS_MODULE,
788	.llseek		= no_llseek,
789	.read		= pp_read,
790	.write		= pp_write,
791	.poll		= pp_poll,
792	.unlocked_ioctl	= pp_ioctl,
793#ifdef CONFIG_COMPAT
794	.compat_ioctl   = pp_compat_ioctl,
795#endif
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	.devmodel	= true,
844};
845
846static int __init ppdev_init(void)
847{
848	int err = 0;
849
850	if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) {
851		pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR);
 
852		return -EIO;
853	}
854	ppdev_class = class_create(THIS_MODULE, CHRDEV);
855	if (IS_ERR(ppdev_class)) {
856		err = PTR_ERR(ppdev_class);
857		goto out_chrdev;
858	}
859	err = parport_register_driver(&pp_driver);
860	if (err < 0) {
861		pr_warn(CHRDEV ": unable to register with parport\n");
862		goto out_class;
863	}
864
865	pr_info(PP_VERSION "\n");
866	goto out;
867
868out_class:
869	class_destroy(ppdev_class);
870out_chrdev:
871	unregister_chrdev(PP_MAJOR, CHRDEV);
872out:
873	return err;
874}
875
876static void __exit ppdev_cleanup(void)
877{
878	/* Clean up all parport stuff */
879	parport_unregister_driver(&pp_driver);
880	class_destroy(ppdev_class);
881	unregister_chrdev(PP_MAJOR, CHRDEV);
882}
883
884module_init(ppdev_init);
885module_exit(ppdev_cleanup);
886
887MODULE_LICENSE("GPL");
888MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);