xref: /openbmc/linux/drivers/char/lp.c (revision 384740dc)
1 /*
2  * Generic parallel printer driver
3  *
4  * Copyright (C) 1992 by Jim Weigand and Linus Torvalds
5  * Copyright (C) 1992,1993 by Michael K. Johnson
6  * - Thanks much to Gunter Windau for pointing out to me where the error
7  *   checking ought to be.
8  * Copyright (C) 1993 by Nigel Gamble (added interrupt code)
9  * Copyright (C) 1994 by Alan Cox (Modularised it)
10  * LPCAREFUL, LPABORT, LPGETSTATUS added by Chris Metcalf, metcalf@lcs.mit.edu
11  * Statistics and support for slow printers by Rob Janssen, rob@knoware.nl
12  * "lp=" command line parameters added by Grant Guenther, grant@torque.net
13  * lp_read (Status readback) support added by Carsten Gross,
14  *                                             carsten@sol.wohnheim.uni-ulm.de
15  * Support for parport by Philip Blundell <philb@gnu.org>
16  * Parport sharing hacking by Andrea Arcangeli
17  * Fixed kernel_(to/from)_user memory copy to check for errors
18  * 				by Riccardo Facchetti <fizban@tin.it>
19  * 22-JAN-1998  Added support for devfs  Richard Gooch <rgooch@atnf.csiro.au>
20  * Redesigned interrupt handling for handle printers with buggy handshake
21  *				by Andrea Arcangeli, 11 May 1998
22  * Full efficient handling of printer with buggy irq handshake (now I have
23  * understood the meaning of the strange handshake). This is done sending new
24  * characters if the interrupt is just happened, even if the printer say to
25  * be still BUSY. This is needed at least with Epson Stylus Color. To enable
26  * the new TRUST_IRQ mode read the `LP OPTIMIZATION' section below...
27  * Fixed the irq on the rising edge of the strobe case.
28  * Obsoleted the CAREFUL flag since a printer that doesn' t work with
29  * CAREFUL will block a bit after in lp_check_status().
30  *				Andrea Arcangeli, 15 Oct 1998
31  * Obsoleted and removed all the lowlevel stuff implemented in the last
32  * month to use the IEEE1284 functions (that handle the _new_ compatibilty
33  * mode fine).
34  */
35 
36 /* This driver should, in theory, work with any parallel port that has an
37  * appropriate low-level driver; all I/O is done through the parport
38  * abstraction layer.
39  *
40  * If this driver is built into the kernel, you can configure it using the
41  * kernel command-line.  For example:
42  *
43  *	lp=parport1,none,parport2	(bind lp0 to parport1, disable lp1 and
44  *					 bind lp2 to parport2)
45  *
46  *	lp=auto				(assign lp devices to all ports that
47  *				         have printers attached, as determined
48  *					 by the IEEE-1284 autoprobe)
49  *
50  *	lp=reset			(reset the printer during
51  *					 initialisation)
52  *
53  *	lp=off				(disable the printer driver entirely)
54  *
55  * If the driver is loaded as a module, similar functionality is available
56  * using module parameters.  The equivalent of the above commands would be:
57  *
58  *	# insmod lp.o parport=1,none,2
59  *
60  *	# insmod lp.o parport=auto
61  *
62  *	# insmod lp.o reset=1
63  */
64 
65 /* COMPATIBILITY WITH OLD KERNELS
66  *
67  * Under Linux 2.0 and previous versions, lp devices were bound to ports at
68  * particular I/O addresses, as follows:
69  *
70  *	lp0		0x3bc
71  *	lp1		0x378
72  *	lp2		0x278
73  *
74  * The new driver, by default, binds lp devices to parport devices as it
75  * finds them.  This means that if you only have one port, it will be bound
76  * to lp0 regardless of its I/O address.  If you need the old behaviour, you
77  * can force it using the parameters described above.
78  */
79 
80 /*
81  * The new interrupt handling code take care of the buggy handshake
82  * of some HP and Epson printer:
83  * ___
84  * ACK    _______________    ___________
85  *                       |__|
86  * ____
87  * BUSY   _________              _______
88  *                 |____________|
89  *
90  * I discovered this using the printer scanner that you can find at:
91  *
92  *	ftp://e-mind.com/pub/linux/pscan/
93  *
94  *					11 May 98, Andrea Arcangeli
95  *
96  * My printer scanner run on an Epson Stylus Color show that such printer
97  * generates the irq on the _rising_ edge of the STROBE. Now lp handle
98  * this case fine too.
99  *
100  *					15 Oct 1998, Andrea Arcangeli
101  *
102  * The so called `buggy' handshake is really the well documented
103  * compatibility mode IEEE1284 handshake. They changed the well known
104  * Centronics handshake acking in the middle of busy expecting to not
105  * break drivers or legacy application, while they broken linux lp
106  * until I fixed it reverse engineering the protocol by hand some
107  * month ago...
108  *
109  *                                     14 Dec 1998, Andrea Arcangeli
110  *
111  * Copyright (C) 2000 by Tim Waugh (added LPSETTIMEOUT ioctl)
112  */
113 
114 #include <linux/module.h>
115 #include <linux/init.h>
116 
117 #include <linux/errno.h>
118 #include <linux/kernel.h>
119 #include <linux/major.h>
120 #include <linux/sched.h>
121 #include <linux/slab.h>
122 #include <linux/fcntl.h>
123 #include <linux/delay.h>
124 #include <linux/poll.h>
125 #include <linux/console.h>
126 #include <linux/device.h>
127 #include <linux/wait.h>
128 #include <linux/jiffies.h>
129 #include <linux/smp_lock.h>
130 
131 #include <linux/parport.h>
132 #undef LP_STATS
133 #include <linux/lp.h>
134 
135 #include <asm/irq.h>
136 #include <asm/uaccess.h>
137 #include <asm/system.h>
138 
139 /* if you have more than 8 printers, remember to increase LP_NO */
140 #define LP_NO 8
141 
142 static struct lp_struct lp_table[LP_NO];
143 
144 static unsigned int lp_count = 0;
145 static struct class *lp_class;
146 
147 #ifdef CONFIG_LP_CONSOLE
148 static struct parport *console_registered;
149 #endif /* CONFIG_LP_CONSOLE */
150 
151 #undef LP_DEBUG
152 
153 /* Bits used to manage claiming the parport device */
154 #define LP_PREEMPT_REQUEST 1
155 #define LP_PARPORT_CLAIMED 2
156 
157 /* --- low-level port access ----------------------------------- */
158 
159 #define r_dtr(x)	(parport_read_data(lp_table[(x)].dev->port))
160 #define r_str(x)	(parport_read_status(lp_table[(x)].dev->port))
161 #define w_ctr(x,y)	do { parport_write_control(lp_table[(x)].dev->port, (y)); } while (0)
162 #define w_dtr(x,y)	do { parport_write_data(lp_table[(x)].dev->port, (y)); } while (0)
163 
164 /* Claim the parport or block trying unless we've already claimed it */
165 static void lp_claim_parport_or_block(struct lp_struct *this_lp)
166 {
167 	if (!test_and_set_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
168 		parport_claim_or_block (this_lp->dev);
169 	}
170 }
171 
172 /* Claim the parport or block trying unless we've already claimed it */
173 static void lp_release_parport(struct lp_struct *this_lp)
174 {
175 	if (test_and_clear_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
176 		parport_release (this_lp->dev);
177 	}
178 }
179 
180 
181 
182 static int lp_preempt(void *handle)
183 {
184 	struct lp_struct *this_lp = (struct lp_struct *)handle;
185 	set_bit(LP_PREEMPT_REQUEST, &this_lp->bits);
186 	return (1);
187 }
188 
189 
190 /*
191  * Try to negotiate to a new mode; if unsuccessful negotiate to
192  * compatibility mode.  Return the mode we ended up in.
193  */
194 static int lp_negotiate(struct parport * port, int mode)
195 {
196 	if (parport_negotiate (port, mode) != 0) {
197 		mode = IEEE1284_MODE_COMPAT;
198 		parport_negotiate (port, mode);
199 	}
200 
201 	return (mode);
202 }
203 
204 static int lp_reset(int minor)
205 {
206 	int retval;
207 	lp_claim_parport_or_block (&lp_table[minor]);
208 	w_ctr(minor, LP_PSELECP);
209 	udelay (LP_DELAY);
210 	w_ctr(minor, LP_PSELECP | LP_PINITP);
211 	retval = r_str(minor);
212 	lp_release_parport (&lp_table[minor]);
213 	return retval;
214 }
215 
216 static void lp_error (int minor)
217 {
218 	DEFINE_WAIT(wait);
219 	int polling;
220 
221 	if (LP_F(minor) & LP_ABORT)
222 		return;
223 
224 	polling = lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE;
225 	if (polling) lp_release_parport (&lp_table[minor]);
226 	prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
227 	schedule_timeout(LP_TIMEOUT_POLLED);
228 	finish_wait(&lp_table[minor].waitq, &wait);
229 	if (polling) lp_claim_parport_or_block (&lp_table[minor]);
230 	else parport_yield_blocking (lp_table[minor].dev);
231 }
232 
233 static int lp_check_status(int minor)
234 {
235 	int error = 0;
236 	unsigned int last = lp_table[minor].last_error;
237 	unsigned char status = r_str(minor);
238 	if ((status & LP_PERRORP) && !(LP_F(minor) & LP_CAREFUL))
239 		/* No error. */
240 		last = 0;
241 	else if ((status & LP_POUTPA)) {
242 		if (last != LP_POUTPA) {
243 			last = LP_POUTPA;
244 			printk(KERN_INFO "lp%d out of paper\n", minor);
245 		}
246 		error = -ENOSPC;
247 	} else if (!(status & LP_PSELECD)) {
248 		if (last != LP_PSELECD) {
249 			last = LP_PSELECD;
250 			printk(KERN_INFO "lp%d off-line\n", minor);
251 		}
252 		error = -EIO;
253 	} else if (!(status & LP_PERRORP)) {
254 		if (last != LP_PERRORP) {
255 			last = LP_PERRORP;
256 			printk(KERN_INFO "lp%d on fire\n", minor);
257 		}
258 		error = -EIO;
259 	} else {
260 		last = 0; /* Come here if LP_CAREFUL is set and no
261                              errors are reported. */
262 	}
263 
264 	lp_table[minor].last_error = last;
265 
266 	if (last != 0)
267 		lp_error(minor);
268 
269 	return error;
270 }
271 
272 static int lp_wait_ready(int minor, int nonblock)
273 {
274 	int error = 0;
275 
276 	/* If we're not in compatibility mode, we're ready now! */
277 	if (lp_table[minor].current_mode != IEEE1284_MODE_COMPAT) {
278 	  return (0);
279 	}
280 
281 	do {
282 		error = lp_check_status (minor);
283 		if (error && (nonblock || (LP_F(minor) & LP_ABORT)))
284 			break;
285 		if (signal_pending (current)) {
286 			error = -EINTR;
287 			break;
288 		}
289 	} while (error);
290 	return error;
291 }
292 
293 static ssize_t lp_write(struct file * file, const char __user * buf,
294 		        size_t count, loff_t *ppos)
295 {
296 	unsigned int minor = iminor(file->f_path.dentry->d_inode);
297 	struct parport *port = lp_table[minor].dev->port;
298 	char *kbuf = lp_table[minor].lp_buffer;
299 	ssize_t retv = 0;
300 	ssize_t written;
301 	size_t copy_size = count;
302 	int nonblock = ((file->f_flags & O_NONBLOCK) ||
303 			(LP_F(minor) & LP_ABORT));
304 
305 #ifdef LP_STATS
306 	if (time_after(jiffies, lp_table[minor].lastcall + LP_TIME(minor)))
307 		lp_table[minor].runchars = 0;
308 
309 	lp_table[minor].lastcall = jiffies;
310 #endif
311 
312 	/* Need to copy the data from user-space. */
313 	if (copy_size > LP_BUFFER_SIZE)
314 		copy_size = LP_BUFFER_SIZE;
315 
316 	if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
317 		return -EINTR;
318 
319 	if (copy_from_user (kbuf, buf, copy_size)) {
320 		retv = -EFAULT;
321 		goto out_unlock;
322 	}
323 
324  	/* Claim Parport or sleep until it becomes available
325  	 */
326 	lp_claim_parport_or_block (&lp_table[minor]);
327 	/* Go to the proper mode. */
328 	lp_table[minor].current_mode = lp_negotiate (port,
329 						     lp_table[minor].best_mode);
330 
331 	parport_set_timeout (lp_table[minor].dev,
332 			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
333 			      : lp_table[minor].timeout));
334 
335 	if ((retv = lp_wait_ready (minor, nonblock)) == 0)
336 	do {
337 		/* Write the data. */
338 		written = parport_write (port, kbuf, copy_size);
339 		if (written > 0) {
340 			copy_size -= written;
341 			count -= written;
342 			buf  += written;
343 			retv += written;
344 		}
345 
346 		if (signal_pending (current)) {
347 			if (retv == 0)
348 				retv = -EINTR;
349 
350 			break;
351 		}
352 
353 		if (copy_size > 0) {
354 			/* incomplete write -> check error ! */
355 			int error;
356 
357 			parport_negotiate (lp_table[minor].dev->port,
358 					   IEEE1284_MODE_COMPAT);
359 			lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
360 
361 			error = lp_wait_ready (minor, nonblock);
362 
363 			if (error) {
364 				if (retv == 0)
365 					retv = error;
366 				break;
367 			} else if (nonblock) {
368 				if (retv == 0)
369 					retv = -EAGAIN;
370 				break;
371 			}
372 
373 			parport_yield_blocking (lp_table[minor].dev);
374 			lp_table[minor].current_mode
375 			  = lp_negotiate (port,
376 					  lp_table[minor].best_mode);
377 
378 		} else if (need_resched())
379 			schedule ();
380 
381 		if (count) {
382 			copy_size = count;
383 			if (copy_size > LP_BUFFER_SIZE)
384 				copy_size = LP_BUFFER_SIZE;
385 
386 			if (copy_from_user(kbuf, buf, copy_size)) {
387 				if (retv == 0)
388 					retv = -EFAULT;
389 				break;
390 			}
391 		}
392 	} while (count > 0);
393 
394 	if (test_and_clear_bit(LP_PREEMPT_REQUEST,
395 			       &lp_table[minor].bits)) {
396 		printk(KERN_INFO "lp%d releasing parport\n", minor);
397 		parport_negotiate (lp_table[minor].dev->port,
398 				   IEEE1284_MODE_COMPAT);
399 		lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
400 		lp_release_parport (&lp_table[minor]);
401 	}
402 out_unlock:
403 	mutex_unlock(&lp_table[minor].port_mutex);
404 
405  	return retv;
406 }
407 
408 #ifdef CONFIG_PARPORT_1284
409 
410 /* Status readback conforming to ieee1284 */
411 static ssize_t lp_read(struct file * file, char __user * buf,
412 		       size_t count, loff_t *ppos)
413 {
414 	DEFINE_WAIT(wait);
415 	unsigned int minor=iminor(file->f_path.dentry->d_inode);
416 	struct parport *port = lp_table[minor].dev->port;
417 	ssize_t retval = 0;
418 	char *kbuf = lp_table[minor].lp_buffer;
419 	int nonblock = ((file->f_flags & O_NONBLOCK) ||
420 			(LP_F(minor) & LP_ABORT));
421 
422 	if (count > LP_BUFFER_SIZE)
423 		count = LP_BUFFER_SIZE;
424 
425 	if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
426 		return -EINTR;
427 
428 	lp_claim_parport_or_block (&lp_table[minor]);
429 
430 	parport_set_timeout (lp_table[minor].dev,
431 			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
432 			      : lp_table[minor].timeout));
433 
434 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
435 	if (parport_negotiate (lp_table[minor].dev->port,
436 			       IEEE1284_MODE_NIBBLE)) {
437 		retval = -EIO;
438 		goto out;
439 	}
440 
441 	while (retval == 0) {
442 		retval = parport_read (port, kbuf, count);
443 
444 		if (retval > 0)
445 			break;
446 
447 		if (nonblock) {
448 			retval = -EAGAIN;
449 			break;
450 		}
451 
452 		/* Wait for data. */
453 
454 		if (lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE) {
455 			parport_negotiate (lp_table[minor].dev->port,
456 					   IEEE1284_MODE_COMPAT);
457 			lp_error (minor);
458 			if (parport_negotiate (lp_table[minor].dev->port,
459 					       IEEE1284_MODE_NIBBLE)) {
460 				retval = -EIO;
461 				goto out;
462 			}
463 		} else {
464 			prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
465 			schedule_timeout(LP_TIMEOUT_POLLED);
466 			finish_wait(&lp_table[minor].waitq, &wait);
467 		}
468 
469 		if (signal_pending (current)) {
470 			retval = -ERESTARTSYS;
471 			break;
472 		}
473 
474 		cond_resched ();
475 	}
476 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
477  out:
478 	lp_release_parport (&lp_table[minor]);
479 
480 	if (retval > 0 && copy_to_user (buf, kbuf, retval))
481 		retval = -EFAULT;
482 
483 	mutex_unlock(&lp_table[minor].port_mutex);
484 
485 	return retval;
486 }
487 
488 #endif /* IEEE 1284 support */
489 
490 static int lp_open(struct inode * inode, struct file * file)
491 {
492 	unsigned int minor = iminor(inode);
493 	int ret = 0;
494 
495 	lock_kernel();
496 	if (minor >= LP_NO) {
497 		ret = -ENXIO;
498 		goto out;
499 	}
500 	if ((LP_F(minor) & LP_EXIST) == 0) {
501 		ret = -ENXIO;
502 		goto out;
503 	}
504 	if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor))) {
505 		ret = -EBUSY;
506 		goto out;
507 	}
508 	/* If ABORTOPEN is set and the printer is offline or out of paper,
509 	   we may still want to open it to perform ioctl()s.  Therefore we
510 	   have commandeered O_NONBLOCK, even though it is being used in
511 	   a non-standard manner.  This is strictly a Linux hack, and
512 	   should most likely only ever be used by the tunelp application. */
513 	if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
514 		int status;
515 		lp_claim_parport_or_block (&lp_table[minor]);
516 		status = r_str(minor);
517 		lp_release_parport (&lp_table[minor]);
518 		if (status & LP_POUTPA) {
519 			printk(KERN_INFO "lp%d out of paper\n", minor);
520 			LP_F(minor) &= ~LP_BUSY;
521 			ret = -ENOSPC;
522 			goto out;
523 		} else if (!(status & LP_PSELECD)) {
524 			printk(KERN_INFO "lp%d off-line\n", minor);
525 			LP_F(minor) &= ~LP_BUSY;
526 			ret = -EIO;
527 			goto out;
528 		} else if (!(status & LP_PERRORP)) {
529 			printk(KERN_ERR "lp%d printer error\n", minor);
530 			LP_F(minor) &= ~LP_BUSY;
531 			ret = -EIO;
532 			goto out;
533 		}
534 	}
535 	lp_table[minor].lp_buffer = kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
536 	if (!lp_table[minor].lp_buffer) {
537 		LP_F(minor) &= ~LP_BUSY;
538 		ret = -ENOMEM;
539 		goto out;
540 	}
541 	/* Determine if the peripheral supports ECP mode */
542 	lp_claim_parport_or_block (&lp_table[minor]);
543 	if ( (lp_table[minor].dev->port->modes & PARPORT_MODE_ECP) &&
544              !parport_negotiate (lp_table[minor].dev->port,
545                                  IEEE1284_MODE_ECP)) {
546 		printk (KERN_INFO "lp%d: ECP mode\n", minor);
547 		lp_table[minor].best_mode = IEEE1284_MODE_ECP;
548 	} else {
549 		lp_table[minor].best_mode = IEEE1284_MODE_COMPAT;
550 	}
551 	/* Leave peripheral in compatibility mode */
552 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
553 	lp_release_parport (&lp_table[minor]);
554 	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
555 out:
556 	unlock_kernel();
557 	return ret;
558 }
559 
560 static int lp_release(struct inode * inode, struct file * file)
561 {
562 	unsigned int minor = iminor(inode);
563 
564 	lp_claim_parport_or_block (&lp_table[minor]);
565 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
566 	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
567 	lp_release_parport (&lp_table[minor]);
568 	kfree(lp_table[minor].lp_buffer);
569 	lp_table[minor].lp_buffer = NULL;
570 	LP_F(minor) &= ~LP_BUSY;
571 	return 0;
572 }
573 
574 static int lp_ioctl(struct inode *inode, struct file *file,
575 		    unsigned int cmd, unsigned long arg)
576 {
577 	unsigned int minor = iminor(inode);
578 	int status;
579 	int retval = 0;
580 	void __user *argp = (void __user *)arg;
581 
582 #ifdef LP_DEBUG
583 	printk(KERN_DEBUG "lp%d ioctl, cmd: 0x%x, arg: 0x%lx\n", minor, cmd, arg);
584 #endif
585 	if (minor >= LP_NO)
586 		return -ENODEV;
587 	if ((LP_F(minor) & LP_EXIST) == 0)
588 		return -ENODEV;
589 	switch ( cmd ) {
590 		struct timeval par_timeout;
591 		long to_jiffies;
592 
593 		case LPTIME:
594 			LP_TIME(minor) = arg * HZ/100;
595 			break;
596 		case LPCHAR:
597 			LP_CHAR(minor) = arg;
598 			break;
599 		case LPABORT:
600 			if (arg)
601 				LP_F(minor) |= LP_ABORT;
602 			else
603 				LP_F(minor) &= ~LP_ABORT;
604 			break;
605 		case LPABORTOPEN:
606 			if (arg)
607 				LP_F(minor) |= LP_ABORTOPEN;
608 			else
609 				LP_F(minor) &= ~LP_ABORTOPEN;
610 			break;
611 		case LPCAREFUL:
612 			if (arg)
613 				LP_F(minor) |= LP_CAREFUL;
614 			else
615 				LP_F(minor) &= ~LP_CAREFUL;
616 			break;
617 		case LPWAIT:
618 			LP_WAIT(minor) = arg;
619 			break;
620 		case LPSETIRQ:
621 			return -EINVAL;
622 			break;
623 		case LPGETIRQ:
624 			if (copy_to_user(argp, &LP_IRQ(minor),
625 					sizeof(int)))
626 				return -EFAULT;
627 			break;
628 		case LPGETSTATUS:
629 			lp_claim_parport_or_block (&lp_table[minor]);
630 			status = r_str(minor);
631 			lp_release_parport (&lp_table[minor]);
632 
633 			if (copy_to_user(argp, &status, sizeof(int)))
634 				return -EFAULT;
635 			break;
636 		case LPRESET:
637 			lp_reset(minor);
638 			break;
639 #ifdef LP_STATS
640 		case LPGETSTATS:
641 			if (copy_to_user(argp, &LP_STAT(minor),
642 					sizeof(struct lp_stats)))
643 				return -EFAULT;
644 			if (capable(CAP_SYS_ADMIN))
645 				memset(&LP_STAT(minor), 0,
646 						sizeof(struct lp_stats));
647 			break;
648 #endif
649  		case LPGETFLAGS:
650  			status = LP_F(minor);
651 			if (copy_to_user(argp, &status, sizeof(int)))
652 				return -EFAULT;
653 			break;
654 
655 		case LPSETTIMEOUT:
656 			if (copy_from_user (&par_timeout, argp,
657 					    sizeof (struct timeval))) {
658 				return -EFAULT;
659 			}
660 			/* Convert to jiffies, place in lp_table */
661 			if ((par_timeout.tv_sec < 0) ||
662 			    (par_timeout.tv_usec < 0)) {
663 				return -EINVAL;
664 			}
665 			to_jiffies = DIV_ROUND_UP(par_timeout.tv_usec, 1000000/HZ);
666 			to_jiffies += par_timeout.tv_sec * (long) HZ;
667 			if (to_jiffies <= 0) {
668 				return -EINVAL;
669 			}
670 			lp_table[minor].timeout = to_jiffies;
671 			break;
672 
673 		default:
674 			retval = -EINVAL;
675 	}
676 	return retval;
677 }
678 
679 static const struct file_operations lp_fops = {
680 	.owner		= THIS_MODULE,
681 	.write		= lp_write,
682 	.ioctl		= lp_ioctl,
683 	.open		= lp_open,
684 	.release	= lp_release,
685 #ifdef CONFIG_PARPORT_1284
686 	.read		= lp_read,
687 #endif
688 };
689 
690 /* --- support for console on the line printer ----------------- */
691 
692 #ifdef CONFIG_LP_CONSOLE
693 
694 #define CONSOLE_LP 0
695 
696 /* If the printer is out of paper, we can either lose the messages or
697  * stall until the printer is happy again.  Define CONSOLE_LP_STRICT
698  * non-zero to get the latter behaviour. */
699 #define CONSOLE_LP_STRICT 1
700 
701 /* The console must be locked when we get here. */
702 
703 static void lp_console_write (struct console *co, const char *s,
704 			      unsigned count)
705 {
706 	struct pardevice *dev = lp_table[CONSOLE_LP].dev;
707 	struct parport *port = dev->port;
708 	ssize_t written;
709 
710 	if (parport_claim (dev))
711 		/* Nothing we can do. */
712 		return;
713 
714 	parport_set_timeout (dev, 0);
715 
716 	/* Go to compatibility mode. */
717 	parport_negotiate (port, IEEE1284_MODE_COMPAT);
718 
719 	do {
720 		/* Write the data, converting LF->CRLF as we go. */
721 		ssize_t canwrite = count;
722 		char *lf = memchr (s, '\n', count);
723 		if (lf)
724 			canwrite = lf - s;
725 
726 		if (canwrite > 0) {
727 			written = parport_write (port, s, canwrite);
728 
729 			if (written <= 0)
730 				continue;
731 
732 			s += written;
733 			count -= written;
734 			canwrite -= written;
735 		}
736 
737 		if (lf && canwrite <= 0) {
738 			const char *crlf = "\r\n";
739 			int i = 2;
740 
741 			/* Dodge the original '\n', and put '\r\n' instead. */
742 			s++;
743 			count--;
744 			do {
745 				written = parport_write (port, crlf, i);
746 				if (written > 0)
747 					i -= written, crlf += written;
748 			} while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
749 		}
750 	} while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
751 
752 	parport_release (dev);
753 }
754 
755 static struct console lpcons = {
756 	.name		= "lp",
757 	.write		= lp_console_write,
758 	.flags		= CON_PRINTBUFFER,
759 };
760 
761 #endif /* console on line printer */
762 
763 /* --- initialisation code ------------------------------------- */
764 
765 static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
766 static char *parport[LP_NO];
767 static int reset;
768 
769 module_param_array(parport, charp, NULL, 0);
770 module_param(reset, bool, 0);
771 
772 #ifndef MODULE
773 static int __init lp_setup (char *str)
774 {
775 	static int parport_ptr;
776 	int x;
777 
778 	if (get_option(&str, &x)) {
779 		if (x == 0) {
780 			/* disable driver on "lp=" or "lp=0" */
781 			parport_nr[0] = LP_PARPORT_OFF;
782 		} else {
783 			printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
784 			return 0;
785 		}
786 	} else if (!strncmp(str, "parport", 7)) {
787 		int n = simple_strtoul(str+7, NULL, 10);
788 		if (parport_ptr < LP_NO)
789 			parport_nr[parport_ptr++] = n;
790 		else
791 			printk(KERN_INFO "lp: too many ports, %s ignored.\n",
792 			       str);
793 	} else if (!strcmp(str, "auto")) {
794 		parport_nr[0] = LP_PARPORT_AUTO;
795 	} else if (!strcmp(str, "none")) {
796 		parport_nr[parport_ptr++] = LP_PARPORT_NONE;
797 	} else if (!strcmp(str, "reset")) {
798 		reset = 1;
799 	}
800 	return 1;
801 }
802 #endif
803 
804 static int lp_register(int nr, struct parport *port)
805 {
806 	lp_table[nr].dev = parport_register_device(port, "lp",
807 						   lp_preempt, NULL, NULL, 0,
808 						   (void *) &lp_table[nr]);
809 	if (lp_table[nr].dev == NULL)
810 		return 1;
811 	lp_table[nr].flags |= LP_EXIST;
812 
813 	if (reset)
814 		lp_reset(nr);
815 
816 	device_create_drvdata(lp_class, port->dev, MKDEV(LP_MAJOR, nr), NULL,
817 			      "lp%d", nr);
818 
819 	printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name,
820 	       (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
821 
822 #ifdef CONFIG_LP_CONSOLE
823 	if (!nr) {
824 		if (port->modes & PARPORT_MODE_SAFEININT) {
825 			register_console(&lpcons);
826 			console_registered = port;
827 			printk (KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
828 		} else
829 			printk (KERN_ERR "lp%d: cannot run console on %s\n",
830 				CONSOLE_LP, port->name);
831 	}
832 #endif
833 
834 	return 0;
835 }
836 
837 static void lp_attach (struct parport *port)
838 {
839 	unsigned int i;
840 
841 	switch (parport_nr[0]) {
842 	case LP_PARPORT_UNSPEC:
843 	case LP_PARPORT_AUTO:
844 		if (parport_nr[0] == LP_PARPORT_AUTO &&
845 		    port->probe_info[0].class != PARPORT_CLASS_PRINTER)
846 			return;
847 		if (lp_count == LP_NO) {
848 			printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
849 			return;
850 		}
851 		if (!lp_register(lp_count, port))
852 			lp_count++;
853 		break;
854 
855 	default:
856 		for (i = 0; i < LP_NO; i++) {
857 			if (port->number == parport_nr[i]) {
858 				if (!lp_register(i, port))
859 					lp_count++;
860 				break;
861 			}
862 		}
863 		break;
864 	}
865 }
866 
867 static void lp_detach (struct parport *port)
868 {
869 	/* Write this some day. */
870 #ifdef CONFIG_LP_CONSOLE
871 	if (console_registered == port) {
872 		unregister_console(&lpcons);
873 		console_registered = NULL;
874 	}
875 #endif /* CONFIG_LP_CONSOLE */
876 }
877 
878 static struct parport_driver lp_driver = {
879 	.name = "lp",
880 	.attach = lp_attach,
881 	.detach = lp_detach,
882 };
883 
884 static int __init lp_init (void)
885 {
886 	int i, err = 0;
887 
888 	if (parport_nr[0] == LP_PARPORT_OFF)
889 		return 0;
890 
891 	for (i = 0; i < LP_NO; i++) {
892 		lp_table[i].dev = NULL;
893 		lp_table[i].flags = 0;
894 		lp_table[i].chars = LP_INIT_CHAR;
895 		lp_table[i].time = LP_INIT_TIME;
896 		lp_table[i].wait = LP_INIT_WAIT;
897 		lp_table[i].lp_buffer = NULL;
898 #ifdef LP_STATS
899 		lp_table[i].lastcall = 0;
900 		lp_table[i].runchars = 0;
901 		memset (&lp_table[i].stats, 0, sizeof (struct lp_stats));
902 #endif
903 		lp_table[i].last_error = 0;
904 		init_waitqueue_head (&lp_table[i].waitq);
905 		init_waitqueue_head (&lp_table[i].dataq);
906 		mutex_init(&lp_table[i].port_mutex);
907 		lp_table[i].timeout = 10 * HZ;
908 	}
909 
910 	if (register_chrdev (LP_MAJOR, "lp", &lp_fops)) {
911 		printk (KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
912 		return -EIO;
913 	}
914 
915 	lp_class = class_create(THIS_MODULE, "printer");
916 	if (IS_ERR(lp_class)) {
917 		err = PTR_ERR(lp_class);
918 		goto out_reg;
919 	}
920 
921 	if (parport_register_driver (&lp_driver)) {
922 		printk (KERN_ERR "lp: unable to register with parport\n");
923 		err = -EIO;
924 		goto out_class;
925 	}
926 
927 	if (!lp_count) {
928 		printk (KERN_INFO "lp: driver loaded but no devices found\n");
929 #ifndef CONFIG_PARPORT_1284
930 		if (parport_nr[0] == LP_PARPORT_AUTO)
931 			printk (KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
932 #endif
933 	}
934 
935 	return 0;
936 
937 out_class:
938 	class_destroy(lp_class);
939 out_reg:
940 	unregister_chrdev(LP_MAJOR, "lp");
941 	return err;
942 }
943 
944 static int __init lp_init_module (void)
945 {
946 	if (parport[0]) {
947 		/* The user gave some parameters.  Let's see what they were.  */
948 		if (!strncmp(parport[0], "auto", 4))
949 			parport_nr[0] = LP_PARPORT_AUTO;
950 		else {
951 			int n;
952 			for (n = 0; n < LP_NO && parport[n]; n++) {
953 				if (!strncmp(parport[n], "none", 4))
954 					parport_nr[n] = LP_PARPORT_NONE;
955 				else {
956 					char *ep;
957 					unsigned long r = simple_strtoul(parport[n], &ep, 0);
958 					if (ep != parport[n])
959 						parport_nr[n] = r;
960 					else {
961 						printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
962 						return -ENODEV;
963 					}
964 				}
965 			}
966 		}
967 	}
968 
969 	return lp_init();
970 }
971 
972 static void lp_cleanup_module (void)
973 {
974 	unsigned int offset;
975 
976 	parport_unregister_driver (&lp_driver);
977 
978 #ifdef CONFIG_LP_CONSOLE
979 	unregister_console (&lpcons);
980 #endif
981 
982 	unregister_chrdev(LP_MAJOR, "lp");
983 	for (offset = 0; offset < LP_NO; offset++) {
984 		if (lp_table[offset].dev == NULL)
985 			continue;
986 		parport_unregister_device(lp_table[offset].dev);
987 		device_destroy(lp_class, MKDEV(LP_MAJOR, offset));
988 	}
989 	class_destroy(lp_class);
990 }
991 
992 __setup("lp=", lp_setup);
993 module_init(lp_init_module);
994 module_exit(lp_cleanup_module);
995 
996 MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
997 MODULE_LICENSE("GPL");
998