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v5.4
  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_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");
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
359	/* First handle the cases that don't take arguments. */
360	switch (cmd) {
361	case PPCLAIM:
362	    {
363		struct ieee1284_info *info;
364		int ret;
365
366		if (pp->flags & PP_CLAIMED) {
367			dev_dbg(&pp->pdev->dev, "you've already got it!\n");
368			return -EINVAL;
369		}
370
371		/* Deferred device registration. */
372		if (!pp->pdev) {
373			int err = register_device(minor, pp);
374
375			if (err)
376				return err;
377		}
378
379		ret = parport_claim_or_block(pp->pdev);
380		if (ret < 0)
381			return ret;
382
383		pp->flags |= PP_CLAIMED;
384
385		/* For interrupt-reporting to work, we need to be
386		 * informed of each interrupt. */
387		pp_enable_irq(pp);
388
389		/* We may need to fix up the state machine. */
390		info = &pp->pdev->port->ieee1284;
391		pp->saved_state.mode = info->mode;
392		pp->saved_state.phase = info->phase;
393		info->mode = pp->state.mode;
394		info->phase = pp->state.phase;
395		pp->default_inactivity = parport_set_timeout(pp->pdev, 0);
396		parport_set_timeout(pp->pdev, pp->default_inactivity);
397
398		return 0;
399	    }
400	case PPEXCL:
401		if (pp->pdev) {
402			dev_dbg(&pp->pdev->dev,
403				"too late for PPEXCL; already registered\n");
404			if (pp->flags & PP_EXCL)
405				/* But it's not really an error. */
406				return 0;
407			/* There's no chance of making the driver happy. */
408			return -EINVAL;
409		}
410
411		/* Just remember to register the device exclusively
412		 * when we finally do the registration. */
413		pp->flags |= PP_EXCL;
414		return 0;
415	case PPSETMODE:
416	    {
417		int mode;
418
419		if (copy_from_user(&mode, argp, sizeof(mode)))
420			return -EFAULT;
421		/* FIXME: validate mode */
422		pp->state.mode = mode;
423		pp->state.phase = init_phase(mode);
424
425		if (pp->flags & PP_CLAIMED) {
426			pp->pdev->port->ieee1284.mode = mode;
427			pp->pdev->port->ieee1284.phase = pp->state.phase;
428		}
429
430		return 0;
431	    }
432	case PPGETMODE:
433	    {
434		int mode;
435
436		if (pp->flags & PP_CLAIMED)
437			mode = pp->pdev->port->ieee1284.mode;
438		else
439			mode = pp->state.mode;
440
441		if (copy_to_user(argp, &mode, sizeof(mode)))
442			return -EFAULT;
443		return 0;
444	    }
445	case PPSETPHASE:
446	    {
447		int phase;
448
449		if (copy_from_user(&phase, argp, sizeof(phase)))
450			return -EFAULT;
451
452		/* FIXME: validate phase */
453		pp->state.phase = phase;
454
455		if (pp->flags & PP_CLAIMED)
456			pp->pdev->port->ieee1284.phase = phase;
457
458		return 0;
459	    }
460	case PPGETPHASE:
461	    {
462		int phase;
463
464		if (pp->flags & PP_CLAIMED)
465			phase = pp->pdev->port->ieee1284.phase;
466		else
467			phase = pp->state.phase;
468		if (copy_to_user(argp, &phase, sizeof(phase)))
469			return -EFAULT;
470		return 0;
471	    }
472	case PPGETMODES:
473	    {
474		unsigned int modes;
475
476		port = parport_find_number(minor);
477		if (!port)
478			return -ENODEV;
479
480		modes = port->modes;
481		parport_put_port(port);
482		if (copy_to_user(argp, &modes, sizeof(modes)))
483			return -EFAULT;
484		return 0;
485	    }
486	case PPSETFLAGS:
487	    {
488		int uflags;
489
490		if (copy_from_user(&uflags, argp, sizeof(uflags)))
491			return -EFAULT;
492		pp->flags &= ~PP_FLAGMASK;
493		pp->flags |= (uflags & PP_FLAGMASK);
494		return 0;
495	    }
496	case PPGETFLAGS:
497	    {
498		int uflags;
499
500		uflags = pp->flags & PP_FLAGMASK;
501		if (copy_to_user(argp, &uflags, sizeof(uflags)))
502			return -EFAULT;
503		return 0;
504	    }
505	}	/* end switch() */
506
507	/* Everything else requires the port to be claimed, so check
508	 * that now. */
509	if ((pp->flags & PP_CLAIMED) == 0) {
510		pr_debug(CHRDEV "%x: claim the port first\n", minor);
511		return -EINVAL;
512	}
513
514	port = pp->pdev->port;
515	switch (cmd) {
516		struct ieee1284_info *info;
517		unsigned char reg;
518		unsigned char mask;
519		int mode;
520		s32 time32[2];
521		s64 time64[2];
522		struct timespec64 ts;
523		int ret;
524
525	case PPRSTATUS:
526		reg = parport_read_status(port);
527		if (copy_to_user(argp, &reg, sizeof(reg)))
528			return -EFAULT;
529		return 0;
530	case PPRDATA:
531		reg = parport_read_data(port);
532		if (copy_to_user(argp, &reg, sizeof(reg)))
533			return -EFAULT;
534		return 0;
535	case PPRCONTROL:
536		reg = parport_read_control(port);
537		if (copy_to_user(argp, &reg, sizeof(reg)))
538			return -EFAULT;
539		return 0;
540	case PPYIELD:
541		parport_yield_blocking(pp->pdev);
542		return 0;
543
544	case PPRELEASE:
545		/* Save the state machine's state. */
546		info = &pp->pdev->port->ieee1284;
547		pp->state.mode = info->mode;
548		pp->state.phase = info->phase;
549		info->mode = pp->saved_state.mode;
550		info->phase = pp->saved_state.phase;
551		parport_release(pp->pdev);
552		pp->flags &= ~PP_CLAIMED;
553		return 0;
554
555	case PPWCONTROL:
556		if (copy_from_user(&reg, argp, sizeof(reg)))
557			return -EFAULT;
558		parport_write_control(port, reg);
559		return 0;
560
561	case PPWDATA:
562		if (copy_from_user(&reg, argp, sizeof(reg)))
563			return -EFAULT;
564		parport_write_data(port, reg);
565		return 0;
566
567	case PPFCONTROL:
568		if (copy_from_user(&mask, argp,
569				   sizeof(mask)))
570			return -EFAULT;
571		if (copy_from_user(&reg, 1 + (unsigned char __user *) arg,
572				   sizeof(reg)))
573			return -EFAULT;
574		parport_frob_control(port, mask, reg);
575		return 0;
576
577	case PPDATADIR:
578		if (copy_from_user(&mode, argp, sizeof(mode)))
579			return -EFAULT;
580		if (mode)
581			port->ops->data_reverse(port);
582		else
583			port->ops->data_forward(port);
584		return 0;
585
586	case PPNEGOT:
587		if (copy_from_user(&mode, argp, sizeof(mode)))
588			return -EFAULT;
589		switch ((ret = parport_negotiate(port, mode))) {
590		case 0: break;
591		case -1: /* handshake failed, peripheral not IEEE 1284 */
592			ret = -EIO;
593			break;
594		case 1:  /* handshake succeeded, peripheral rejected mode */
595			ret = -ENXIO;
596			break;
597		}
598		pp_enable_irq(pp);
599		return ret;
600
601	case PPWCTLONIRQ:
602		if (copy_from_user(&reg, argp, sizeof(reg)))
603			return -EFAULT;
604
605		/* Remember what to set the control lines to, for next
606		 * time we get an interrupt. */
607		pp->irqctl = reg;
608		pp->irqresponse = 1;
609		return 0;
610
611	case PPCLRIRQ:
612		ret = atomic_read(&pp->irqc);
613		if (copy_to_user(argp, &ret, sizeof(ret)))
614			return -EFAULT;
615		atomic_sub(ret, &pp->irqc);
616		return 0;
617
618	case PPSETTIME32:
619		if (copy_from_user(time32, argp, sizeof(time32)))
620			return -EFAULT;
621
622		return pp_set_timeout(pp->pdev, time32[0], time32[1]);
623
624	case PPSETTIME64:
625		if (copy_from_user(time64, argp, sizeof(time64)))
626			return -EFAULT;
627
628		return pp_set_timeout(pp->pdev, time64[0], time64[1]);
629
630	case PPGETTIME32:
631		jiffies_to_timespec64(pp->pdev->timeout, &ts);
632		time32[0] = ts.tv_sec;
633		time32[1] = ts.tv_nsec / NSEC_PER_USEC;
634		if ((time32[0] < 0) || (time32[1] < 0))
635			return -EINVAL;
636
637		if (copy_to_user(argp, time32, sizeof(time32)))
638			return -EFAULT;
639
640		return 0;
641
642	case PPGETTIME64:
643		jiffies_to_timespec64(pp->pdev->timeout, &ts);
644		time64[0] = ts.tv_sec;
645		time64[1] = ts.tv_nsec / NSEC_PER_USEC;
646		if ((time64[0] < 0) || (time64[1] < 0))
647			return -EINVAL;
648
649		if (copy_to_user(argp, time64, sizeof(time64)))
650			return -EFAULT;
651
652		return 0;
653
654	default:
655		dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd);
656		return -EINVAL;
657	}
658
659	/* Keep the compiler happy */
660	return 0;
661}
662
663static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
664{
665	long ret;
666
667	mutex_lock(&pp_do_mutex);
668	ret = pp_do_ioctl(file, cmd, arg);
669	mutex_unlock(&pp_do_mutex);
670	return ret;
671}
672
673#ifdef CONFIG_COMPAT
674static long pp_compat_ioctl(struct file *file, unsigned int cmd,
675			    unsigned long arg)
676{
677	return pp_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
678}
679#endif
680
681static int pp_open(struct inode *inode, struct file *file)
682{
683	unsigned int minor = iminor(inode);
684	struct pp_struct *pp;
685
686	if (minor >= PARPORT_MAX)
687		return -ENXIO;
688
689	pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL);
690	if (!pp)
691		return -ENOMEM;
692
693	pp->state.mode = IEEE1284_MODE_COMPAT;
694	pp->state.phase = init_phase(pp->state.mode);
695	pp->flags = 0;
696	pp->irqresponse = 0;
697	atomic_set(&pp->irqc, 0);
698	init_waitqueue_head(&pp->irq_wait);
699
700	/* Defer the actual device registration until the first claim.
701	 * That way, we know whether or not the driver wants to have
702	 * exclusive access to the port (PPEXCL).
703	 */
704	pp->pdev = NULL;
705	file->private_data = pp;
706
707	return 0;
708}
709
710static int pp_release(struct inode *inode, struct file *file)
711{
712	unsigned int minor = iminor(inode);
713	struct pp_struct *pp = file->private_data;
714	int compat_negot;
715
716	compat_negot = 0;
717	if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
718	    (pp->state.mode != IEEE1284_MODE_COMPAT)) {
719		struct ieee1284_info *info;
720
721		/* parport released, but not in compatibility mode */
722		parport_claim_or_block(pp->pdev);
723		pp->flags |= PP_CLAIMED;
724		info = &pp->pdev->port->ieee1284;
725		pp->saved_state.mode = info->mode;
726		pp->saved_state.phase = info->phase;
727		info->mode = pp->state.mode;
728		info->phase = pp->state.phase;
729		compat_negot = 1;
730	} else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
731	    (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
732		compat_negot = 2;
733	}
734	if (compat_negot) {
735		parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT);
736		dev_dbg(&pp->pdev->dev,
737			"negotiated back to compatibility mode because user-space forgot\n");
738	}
739
740	if ((pp->flags & PP_CLAIMED) && pp->pdev) {
741		struct ieee1284_info *info;
742
743		info = &pp->pdev->port->ieee1284;
744		pp->state.mode = info->mode;
745		pp->state.phase = info->phase;
746		info->mode = pp->saved_state.mode;
747		info->phase = pp->saved_state.phase;
748		parport_release(pp->pdev);
749		if (compat_negot != 1) {
750			pr_debug(CHRDEV "%x: released pardevice "
751				"because user-space forgot\n", minor);
752		}
753	}
754
755	if (pp->pdev) {
 
 
756		parport_unregister_device(pp->pdev);
757		ida_simple_remove(&ida_index, pp->index);
758		pp->pdev = NULL;
759		pr_debug(CHRDEV "%x: unregistered pardevice\n", minor);
760	}
761
762	kfree(pp);
763
764	return 0;
765}
766
767/* No kernel lock held - fine */
768static __poll_t pp_poll(struct file *file, poll_table *wait)
769{
770	struct pp_struct *pp = file->private_data;
771	__poll_t mask = 0;
772
773	poll_wait(file, &pp->irq_wait, wait);
774	if (atomic_read(&pp->irqc))
775		mask |= EPOLLIN | EPOLLRDNORM;
776
777	return mask;
778}
779
780static struct class *ppdev_class;
781
782static const struct file_operations pp_fops = {
783	.owner		= THIS_MODULE,
784	.llseek		= no_llseek,
785	.read		= pp_read,
786	.write		= pp_write,
787	.poll		= pp_poll,
788	.unlocked_ioctl	= pp_ioctl,
789#ifdef CONFIG_COMPAT
790	.compat_ioctl   = pp_compat_ioctl,
791#endif
792	.open		= pp_open,
793	.release	= pp_release,
794};
795
796static void pp_attach(struct parport *port)
797{
798	struct device *ret;
799
800	if (devices[port->number])
801		return;
802
803	ret = device_create(ppdev_class, port->dev,
804			    MKDEV(PP_MAJOR, port->number), NULL,
805			    "parport%d", port->number);
806	if (IS_ERR(ret)) {
807		pr_err("Failed to create device parport%d\n",
808		       port->number);
809		return;
810	}
811	devices[port->number] = ret;
812}
813
814static void pp_detach(struct parport *port)
815{
816	if (!devices[port->number])
817		return;
818
819	device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number));
820	devices[port->number] = NULL;
821}
822
823static int pp_probe(struct pardevice *par_dev)
824{
825	struct device_driver *drv = par_dev->dev.driver;
826	int len = strlen(drv->name);
827
828	if (strncmp(par_dev->name, drv->name, len))
829		return -ENODEV;
830
831	return 0;
832}
833
834static struct parport_driver pp_driver = {
835	.name		= CHRDEV,
836	.probe		= pp_probe,
837	.match_port	= pp_attach,
838	.detach		= pp_detach,
839	.devmodel	= true,
840};
841
842static int __init ppdev_init(void)
843{
844	int err = 0;
845
846	if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) {
847		pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR);
 
848		return -EIO;
849	}
850	ppdev_class = class_create(THIS_MODULE, CHRDEV);
851	if (IS_ERR(ppdev_class)) {
852		err = PTR_ERR(ppdev_class);
853		goto out_chrdev;
854	}
855	err = parport_register_driver(&pp_driver);
856	if (err < 0) {
857		pr_warn(CHRDEV ": unable to register with parport\n");
858		goto out_class;
859	}
860
861	pr_info(PP_VERSION "\n");
862	goto out;
863
864out_class:
865	class_destroy(ppdev_class);
866out_chrdev:
867	unregister_chrdev(PP_MAJOR, CHRDEV);
868out:
869	return err;
870}
871
872static void __exit ppdev_cleanup(void)
873{
874	/* Clean up all parport stuff */
875	parport_unregister_driver(&pp_driver);
876	class_destroy(ppdev_class);
877	unregister_chrdev(PP_MAJOR, CHRDEV);
878}
879
880module_init(ppdev_init);
881module_exit(ppdev_cleanup);
882
883MODULE_LICENSE("GPL");
884MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);
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);