xref: /openbmc/linux/drivers/char/lp.c (revision 1eb4c977)
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/mutex.h>
130 #include <linux/compat.h>
131 
132 #include <linux/parport.h>
133 #undef LP_STATS
134 #include <linux/lp.h>
135 
136 #include <asm/irq.h>
137 #include <asm/uaccess.h>
138 #include <asm/system.h>
139 
140 /* if you have more than 8 printers, remember to increase LP_NO */
141 #define LP_NO 8
142 
143 static DEFINE_MUTEX(lp_mutex);
144 static struct lp_struct lp_table[LP_NO];
145 
146 static unsigned int lp_count = 0;
147 static struct class *lp_class;
148 
149 #ifdef CONFIG_LP_CONSOLE
150 static struct parport *console_registered;
151 #endif /* CONFIG_LP_CONSOLE */
152 
153 #undef LP_DEBUG
154 
155 /* Bits used to manage claiming the parport device */
156 #define LP_PREEMPT_REQUEST 1
157 #define LP_PARPORT_CLAIMED 2
158 
159 /* --- low-level port access ----------------------------------- */
160 
161 #define r_dtr(x)	(parport_read_data(lp_table[(x)].dev->port))
162 #define r_str(x)	(parport_read_status(lp_table[(x)].dev->port))
163 #define w_ctr(x,y)	do { parport_write_control(lp_table[(x)].dev->port, (y)); } while (0)
164 #define w_dtr(x,y)	do { parport_write_data(lp_table[(x)].dev->port, (y)); } while (0)
165 
166 /* Claim the parport or block trying unless we've already claimed it */
167 static void lp_claim_parport_or_block(struct lp_struct *this_lp)
168 {
169 	if (!test_and_set_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
170 		parport_claim_or_block (this_lp->dev);
171 	}
172 }
173 
174 /* Claim the parport or block trying unless we've already claimed it */
175 static void lp_release_parport(struct lp_struct *this_lp)
176 {
177 	if (test_and_clear_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
178 		parport_release (this_lp->dev);
179 	}
180 }
181 
182 
183 
184 static int lp_preempt(void *handle)
185 {
186 	struct lp_struct *this_lp = (struct lp_struct *)handle;
187 	set_bit(LP_PREEMPT_REQUEST, &this_lp->bits);
188 	return (1);
189 }
190 
191 
192 /*
193  * Try to negotiate to a new mode; if unsuccessful negotiate to
194  * compatibility mode.  Return the mode we ended up in.
195  */
196 static int lp_negotiate(struct parport * port, int mode)
197 {
198 	if (parport_negotiate (port, mode) != 0) {
199 		mode = IEEE1284_MODE_COMPAT;
200 		parport_negotiate (port, mode);
201 	}
202 
203 	return (mode);
204 }
205 
206 static int lp_reset(int minor)
207 {
208 	int retval;
209 	lp_claim_parport_or_block (&lp_table[minor]);
210 	w_ctr(minor, LP_PSELECP);
211 	udelay (LP_DELAY);
212 	w_ctr(minor, LP_PSELECP | LP_PINITP);
213 	retval = r_str(minor);
214 	lp_release_parport (&lp_table[minor]);
215 	return retval;
216 }
217 
218 static void lp_error (int minor)
219 {
220 	DEFINE_WAIT(wait);
221 	int polling;
222 
223 	if (LP_F(minor) & LP_ABORT)
224 		return;
225 
226 	polling = lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE;
227 	if (polling) lp_release_parport (&lp_table[minor]);
228 	prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
229 	schedule_timeout(LP_TIMEOUT_POLLED);
230 	finish_wait(&lp_table[minor].waitq, &wait);
231 	if (polling) lp_claim_parport_or_block (&lp_table[minor]);
232 	else parport_yield_blocking (lp_table[minor].dev);
233 }
234 
235 static int lp_check_status(int minor)
236 {
237 	int error = 0;
238 	unsigned int last = lp_table[minor].last_error;
239 	unsigned char status = r_str(minor);
240 	if ((status & LP_PERRORP) && !(LP_F(minor) & LP_CAREFUL))
241 		/* No error. */
242 		last = 0;
243 	else if ((status & LP_POUTPA)) {
244 		if (last != LP_POUTPA) {
245 			last = LP_POUTPA;
246 			printk(KERN_INFO "lp%d out of paper\n", minor);
247 		}
248 		error = -ENOSPC;
249 	} else if (!(status & LP_PSELECD)) {
250 		if (last != LP_PSELECD) {
251 			last = LP_PSELECD;
252 			printk(KERN_INFO "lp%d off-line\n", minor);
253 		}
254 		error = -EIO;
255 	} else if (!(status & LP_PERRORP)) {
256 		if (last != LP_PERRORP) {
257 			last = LP_PERRORP;
258 			printk(KERN_INFO "lp%d on fire\n", minor);
259 		}
260 		error = -EIO;
261 	} else {
262 		last = 0; /* Come here if LP_CAREFUL is set and no
263                              errors are reported. */
264 	}
265 
266 	lp_table[minor].last_error = last;
267 
268 	if (last != 0)
269 		lp_error(minor);
270 
271 	return error;
272 }
273 
274 static int lp_wait_ready(int minor, int nonblock)
275 {
276 	int error = 0;
277 
278 	/* If we're not in compatibility mode, we're ready now! */
279 	if (lp_table[minor].current_mode != IEEE1284_MODE_COMPAT) {
280 	  return (0);
281 	}
282 
283 	do {
284 		error = lp_check_status (minor);
285 		if (error && (nonblock || (LP_F(minor) & LP_ABORT)))
286 			break;
287 		if (signal_pending (current)) {
288 			error = -EINTR;
289 			break;
290 		}
291 	} while (error);
292 	return error;
293 }
294 
295 static ssize_t lp_write(struct file * file, const char __user * buf,
296 		        size_t count, loff_t *ppos)
297 {
298 	unsigned int minor = iminor(file->f_path.dentry->d_inode);
299 	struct parport *port = lp_table[minor].dev->port;
300 	char *kbuf = lp_table[minor].lp_buffer;
301 	ssize_t retv = 0;
302 	ssize_t written;
303 	size_t copy_size = count;
304 	int nonblock = ((file->f_flags & O_NONBLOCK) ||
305 			(LP_F(minor) & LP_ABORT));
306 
307 #ifdef LP_STATS
308 	if (time_after(jiffies, lp_table[minor].lastcall + LP_TIME(minor)))
309 		lp_table[minor].runchars = 0;
310 
311 	lp_table[minor].lastcall = jiffies;
312 #endif
313 
314 	/* Need to copy the data from user-space. */
315 	if (copy_size > LP_BUFFER_SIZE)
316 		copy_size = LP_BUFFER_SIZE;
317 
318 	if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
319 		return -EINTR;
320 
321 	if (copy_from_user (kbuf, buf, copy_size)) {
322 		retv = -EFAULT;
323 		goto out_unlock;
324 	}
325 
326  	/* Claim Parport or sleep until it becomes available
327  	 */
328 	lp_claim_parport_or_block (&lp_table[minor]);
329 	/* Go to the proper mode. */
330 	lp_table[minor].current_mode = lp_negotiate (port,
331 						     lp_table[minor].best_mode);
332 
333 	parport_set_timeout (lp_table[minor].dev,
334 			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
335 			      : lp_table[minor].timeout));
336 
337 	if ((retv = lp_wait_ready (minor, nonblock)) == 0)
338 	do {
339 		/* Write the data. */
340 		written = parport_write (port, kbuf, copy_size);
341 		if (written > 0) {
342 			copy_size -= written;
343 			count -= written;
344 			buf  += written;
345 			retv += written;
346 		}
347 
348 		if (signal_pending (current)) {
349 			if (retv == 0)
350 				retv = -EINTR;
351 
352 			break;
353 		}
354 
355 		if (copy_size > 0) {
356 			/* incomplete write -> check error ! */
357 			int error;
358 
359 			parport_negotiate (lp_table[minor].dev->port,
360 					   IEEE1284_MODE_COMPAT);
361 			lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
362 
363 			error = lp_wait_ready (minor, nonblock);
364 
365 			if (error) {
366 				if (retv == 0)
367 					retv = error;
368 				break;
369 			} else if (nonblock) {
370 				if (retv == 0)
371 					retv = -EAGAIN;
372 				break;
373 			}
374 
375 			parport_yield_blocking (lp_table[minor].dev);
376 			lp_table[minor].current_mode
377 			  = lp_negotiate (port,
378 					  lp_table[minor].best_mode);
379 
380 		} else if (need_resched())
381 			schedule ();
382 
383 		if (count) {
384 			copy_size = count;
385 			if (copy_size > LP_BUFFER_SIZE)
386 				copy_size = LP_BUFFER_SIZE;
387 
388 			if (copy_from_user(kbuf, buf, copy_size)) {
389 				if (retv == 0)
390 					retv = -EFAULT;
391 				break;
392 			}
393 		}
394 	} while (count > 0);
395 
396 	if (test_and_clear_bit(LP_PREEMPT_REQUEST,
397 			       &lp_table[minor].bits)) {
398 		printk(KERN_INFO "lp%d releasing parport\n", minor);
399 		parport_negotiate (lp_table[minor].dev->port,
400 				   IEEE1284_MODE_COMPAT);
401 		lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
402 		lp_release_parport (&lp_table[minor]);
403 	}
404 out_unlock:
405 	mutex_unlock(&lp_table[minor].port_mutex);
406 
407  	return retv;
408 }
409 
410 #ifdef CONFIG_PARPORT_1284
411 
412 /* Status readback conforming to ieee1284 */
413 static ssize_t lp_read(struct file * file, char __user * buf,
414 		       size_t count, loff_t *ppos)
415 {
416 	DEFINE_WAIT(wait);
417 	unsigned int minor=iminor(file->f_path.dentry->d_inode);
418 	struct parport *port = lp_table[minor].dev->port;
419 	ssize_t retval = 0;
420 	char *kbuf = lp_table[minor].lp_buffer;
421 	int nonblock = ((file->f_flags & O_NONBLOCK) ||
422 			(LP_F(minor) & LP_ABORT));
423 
424 	if (count > LP_BUFFER_SIZE)
425 		count = LP_BUFFER_SIZE;
426 
427 	if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
428 		return -EINTR;
429 
430 	lp_claim_parport_or_block (&lp_table[minor]);
431 
432 	parport_set_timeout (lp_table[minor].dev,
433 			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
434 			      : lp_table[minor].timeout));
435 
436 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
437 	if (parport_negotiate (lp_table[minor].dev->port,
438 			       IEEE1284_MODE_NIBBLE)) {
439 		retval = -EIO;
440 		goto out;
441 	}
442 
443 	while (retval == 0) {
444 		retval = parport_read (port, kbuf, count);
445 
446 		if (retval > 0)
447 			break;
448 
449 		if (nonblock) {
450 			retval = -EAGAIN;
451 			break;
452 		}
453 
454 		/* Wait for data. */
455 
456 		if (lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE) {
457 			parport_negotiate (lp_table[minor].dev->port,
458 					   IEEE1284_MODE_COMPAT);
459 			lp_error (minor);
460 			if (parport_negotiate (lp_table[minor].dev->port,
461 					       IEEE1284_MODE_NIBBLE)) {
462 				retval = -EIO;
463 				goto out;
464 			}
465 		} else {
466 			prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
467 			schedule_timeout(LP_TIMEOUT_POLLED);
468 			finish_wait(&lp_table[minor].waitq, &wait);
469 		}
470 
471 		if (signal_pending (current)) {
472 			retval = -ERESTARTSYS;
473 			break;
474 		}
475 
476 		cond_resched ();
477 	}
478 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
479  out:
480 	lp_release_parport (&lp_table[minor]);
481 
482 	if (retval > 0 && copy_to_user (buf, kbuf, retval))
483 		retval = -EFAULT;
484 
485 	mutex_unlock(&lp_table[minor].port_mutex);
486 
487 	return retval;
488 }
489 
490 #endif /* IEEE 1284 support */
491 
492 static int lp_open(struct inode * inode, struct file * file)
493 {
494 	unsigned int minor = iminor(inode);
495 	int ret = 0;
496 
497 	mutex_lock(&lp_mutex);
498 	if (minor >= LP_NO) {
499 		ret = -ENXIO;
500 		goto out;
501 	}
502 	if ((LP_F(minor) & LP_EXIST) == 0) {
503 		ret = -ENXIO;
504 		goto out;
505 	}
506 	if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor))) {
507 		ret = -EBUSY;
508 		goto out;
509 	}
510 	/* If ABORTOPEN is set and the printer is offline or out of paper,
511 	   we may still want to open it to perform ioctl()s.  Therefore we
512 	   have commandeered O_NONBLOCK, even though it is being used in
513 	   a non-standard manner.  This is strictly a Linux hack, and
514 	   should most likely only ever be used by the tunelp application. */
515 	if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
516 		int status;
517 		lp_claim_parport_or_block (&lp_table[minor]);
518 		status = r_str(minor);
519 		lp_release_parport (&lp_table[minor]);
520 		if (status & LP_POUTPA) {
521 			printk(KERN_INFO "lp%d out of paper\n", minor);
522 			LP_F(minor) &= ~LP_BUSY;
523 			ret = -ENOSPC;
524 			goto out;
525 		} else if (!(status & LP_PSELECD)) {
526 			printk(KERN_INFO "lp%d off-line\n", minor);
527 			LP_F(minor) &= ~LP_BUSY;
528 			ret = -EIO;
529 			goto out;
530 		} else if (!(status & LP_PERRORP)) {
531 			printk(KERN_ERR "lp%d printer error\n", minor);
532 			LP_F(minor) &= ~LP_BUSY;
533 			ret = -EIO;
534 			goto out;
535 		}
536 	}
537 	lp_table[minor].lp_buffer = kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
538 	if (!lp_table[minor].lp_buffer) {
539 		LP_F(minor) &= ~LP_BUSY;
540 		ret = -ENOMEM;
541 		goto out;
542 	}
543 	/* Determine if the peripheral supports ECP mode */
544 	lp_claim_parport_or_block (&lp_table[minor]);
545 	if ( (lp_table[minor].dev->port->modes & PARPORT_MODE_ECP) &&
546              !parport_negotiate (lp_table[minor].dev->port,
547                                  IEEE1284_MODE_ECP)) {
548 		printk (KERN_INFO "lp%d: ECP mode\n", minor);
549 		lp_table[minor].best_mode = IEEE1284_MODE_ECP;
550 	} else {
551 		lp_table[minor].best_mode = IEEE1284_MODE_COMPAT;
552 	}
553 	/* Leave peripheral in compatibility mode */
554 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
555 	lp_release_parport (&lp_table[minor]);
556 	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
557 out:
558 	mutex_unlock(&lp_mutex);
559 	return ret;
560 }
561 
562 static int lp_release(struct inode * inode, struct file * file)
563 {
564 	unsigned int minor = iminor(inode);
565 
566 	lp_claim_parport_or_block (&lp_table[minor]);
567 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
568 	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
569 	lp_release_parport (&lp_table[minor]);
570 	kfree(lp_table[minor].lp_buffer);
571 	lp_table[minor].lp_buffer = NULL;
572 	LP_F(minor) &= ~LP_BUSY;
573 	return 0;
574 }
575 
576 static int lp_do_ioctl(unsigned int minor, unsigned int cmd,
577 	unsigned long arg, void __user *argp)
578 {
579 	int status;
580 	int retval = 0;
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 		case LPTIME:
591 			LP_TIME(minor) = arg * HZ/100;
592 			break;
593 		case LPCHAR:
594 			LP_CHAR(minor) = arg;
595 			break;
596 		case LPABORT:
597 			if (arg)
598 				LP_F(minor) |= LP_ABORT;
599 			else
600 				LP_F(minor) &= ~LP_ABORT;
601 			break;
602 		case LPABORTOPEN:
603 			if (arg)
604 				LP_F(minor) |= LP_ABORTOPEN;
605 			else
606 				LP_F(minor) &= ~LP_ABORTOPEN;
607 			break;
608 		case LPCAREFUL:
609 			if (arg)
610 				LP_F(minor) |= LP_CAREFUL;
611 			else
612 				LP_F(minor) &= ~LP_CAREFUL;
613 			break;
614 		case LPWAIT:
615 			LP_WAIT(minor) = arg;
616 			break;
617 		case LPSETIRQ:
618 			return -EINVAL;
619 			break;
620 		case LPGETIRQ:
621 			if (copy_to_user(argp, &LP_IRQ(minor),
622 					sizeof(int)))
623 				return -EFAULT;
624 			break;
625 		case LPGETSTATUS:
626 			lp_claim_parport_or_block (&lp_table[minor]);
627 			status = r_str(minor);
628 			lp_release_parport (&lp_table[minor]);
629 
630 			if (copy_to_user(argp, &status, sizeof(int)))
631 				return -EFAULT;
632 			break;
633 		case LPRESET:
634 			lp_reset(minor);
635 			break;
636 #ifdef LP_STATS
637 		case LPGETSTATS:
638 			if (copy_to_user(argp, &LP_STAT(minor),
639 					sizeof(struct lp_stats)))
640 				return -EFAULT;
641 			if (capable(CAP_SYS_ADMIN))
642 				memset(&LP_STAT(minor), 0,
643 						sizeof(struct lp_stats));
644 			break;
645 #endif
646  		case LPGETFLAGS:
647  			status = LP_F(minor);
648 			if (copy_to_user(argp, &status, sizeof(int)))
649 				return -EFAULT;
650 			break;
651 
652 		default:
653 			retval = -EINVAL;
654 	}
655 	return retval;
656 }
657 
658 static int lp_set_timeout(unsigned int minor, struct timeval *par_timeout)
659 {
660 	long to_jiffies;
661 
662 	/* Convert to jiffies, place in lp_table */
663 	if ((par_timeout->tv_sec < 0) ||
664 	    (par_timeout->tv_usec < 0)) {
665 		return -EINVAL;
666 	}
667 	to_jiffies = DIV_ROUND_UP(par_timeout->tv_usec, 1000000/HZ);
668 	to_jiffies += par_timeout->tv_sec * (long) HZ;
669 	if (to_jiffies <= 0) {
670 		return -EINVAL;
671 	}
672 	lp_table[minor].timeout = to_jiffies;
673 	return 0;
674 }
675 
676 static long lp_ioctl(struct file *file, unsigned int cmd,
677 			unsigned long arg)
678 {
679 	unsigned int minor;
680 	struct timeval par_timeout;
681 	int ret;
682 
683 	minor = iminor(file->f_path.dentry->d_inode);
684 	mutex_lock(&lp_mutex);
685 	switch (cmd) {
686 	case LPSETTIMEOUT:
687 		if (copy_from_user(&par_timeout, (void __user *)arg,
688 					sizeof (struct timeval))) {
689 			ret = -EFAULT;
690 			break;
691 		}
692 		ret = lp_set_timeout(minor, &par_timeout);
693 		break;
694 	default:
695 		ret = lp_do_ioctl(minor, cmd, arg, (void __user *)arg);
696 		break;
697 	}
698 	mutex_unlock(&lp_mutex);
699 
700 	return ret;
701 }
702 
703 #ifdef CONFIG_COMPAT
704 static long lp_compat_ioctl(struct file *file, unsigned int cmd,
705 			unsigned long arg)
706 {
707 	unsigned int minor;
708 	struct timeval par_timeout;
709 	struct compat_timeval __user *tc;
710 	int ret;
711 
712 	minor = iminor(file->f_path.dentry->d_inode);
713 	mutex_lock(&lp_mutex);
714 	switch (cmd) {
715 	case LPSETTIMEOUT:
716 		tc = compat_ptr(arg);
717 		if (get_user(par_timeout.tv_sec, &tc->tv_sec) ||
718 		    get_user(par_timeout.tv_usec, &tc->tv_usec)) {
719 			ret = -EFAULT;
720 			break;
721 		}
722 		ret = lp_set_timeout(minor, &par_timeout);
723 		break;
724 #ifdef LP_STATS
725 	case LPGETSTATS:
726 		/* FIXME: add an implementation if you set LP_STATS */
727 		ret = -EINVAL;
728 		break;
729 #endif
730 	default:
731 		ret = lp_do_ioctl(minor, cmd, arg, compat_ptr(arg));
732 		break;
733 	}
734 	mutex_unlock(&lp_mutex);
735 
736 	return ret;
737 }
738 #endif
739 
740 static const struct file_operations lp_fops = {
741 	.owner		= THIS_MODULE,
742 	.write		= lp_write,
743 	.unlocked_ioctl	= lp_ioctl,
744 #ifdef CONFIG_COMPAT
745 	.compat_ioctl	= lp_compat_ioctl,
746 #endif
747 	.open		= lp_open,
748 	.release	= lp_release,
749 #ifdef CONFIG_PARPORT_1284
750 	.read		= lp_read,
751 #endif
752 	.llseek		= noop_llseek,
753 };
754 
755 /* --- support for console on the line printer ----------------- */
756 
757 #ifdef CONFIG_LP_CONSOLE
758 
759 #define CONSOLE_LP 0
760 
761 /* If the printer is out of paper, we can either lose the messages or
762  * stall until the printer is happy again.  Define CONSOLE_LP_STRICT
763  * non-zero to get the latter behaviour. */
764 #define CONSOLE_LP_STRICT 1
765 
766 /* The console must be locked when we get here. */
767 
768 static void lp_console_write (struct console *co, const char *s,
769 			      unsigned count)
770 {
771 	struct pardevice *dev = lp_table[CONSOLE_LP].dev;
772 	struct parport *port = dev->port;
773 	ssize_t written;
774 
775 	if (parport_claim (dev))
776 		/* Nothing we can do. */
777 		return;
778 
779 	parport_set_timeout (dev, 0);
780 
781 	/* Go to compatibility mode. */
782 	parport_negotiate (port, IEEE1284_MODE_COMPAT);
783 
784 	do {
785 		/* Write the data, converting LF->CRLF as we go. */
786 		ssize_t canwrite = count;
787 		char *lf = memchr (s, '\n', count);
788 		if (lf)
789 			canwrite = lf - s;
790 
791 		if (canwrite > 0) {
792 			written = parport_write (port, s, canwrite);
793 
794 			if (written <= 0)
795 				continue;
796 
797 			s += written;
798 			count -= written;
799 			canwrite -= written;
800 		}
801 
802 		if (lf && canwrite <= 0) {
803 			const char *crlf = "\r\n";
804 			int i = 2;
805 
806 			/* Dodge the original '\n', and put '\r\n' instead. */
807 			s++;
808 			count--;
809 			do {
810 				written = parport_write (port, crlf, i);
811 				if (written > 0)
812 					i -= written, crlf += written;
813 			} while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
814 		}
815 	} while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
816 
817 	parport_release (dev);
818 }
819 
820 static struct console lpcons = {
821 	.name		= "lp",
822 	.write		= lp_console_write,
823 	.flags		= CON_PRINTBUFFER,
824 };
825 
826 #endif /* console on line printer */
827 
828 /* --- initialisation code ------------------------------------- */
829 
830 static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
831 static char *parport[LP_NO];
832 static bool reset;
833 
834 module_param_array(parport, charp, NULL, 0);
835 module_param(reset, bool, 0);
836 
837 #ifndef MODULE
838 static int __init lp_setup (char *str)
839 {
840 	static int parport_ptr;
841 	int x;
842 
843 	if (get_option(&str, &x)) {
844 		if (x == 0) {
845 			/* disable driver on "lp=" or "lp=0" */
846 			parport_nr[0] = LP_PARPORT_OFF;
847 		} else {
848 			printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
849 			return 0;
850 		}
851 	} else if (!strncmp(str, "parport", 7)) {
852 		int n = simple_strtoul(str+7, NULL, 10);
853 		if (parport_ptr < LP_NO)
854 			parport_nr[parport_ptr++] = n;
855 		else
856 			printk(KERN_INFO "lp: too many ports, %s ignored.\n",
857 			       str);
858 	} else if (!strcmp(str, "auto")) {
859 		parport_nr[0] = LP_PARPORT_AUTO;
860 	} else if (!strcmp(str, "none")) {
861 		parport_nr[parport_ptr++] = LP_PARPORT_NONE;
862 	} else if (!strcmp(str, "reset")) {
863 		reset = 1;
864 	}
865 	return 1;
866 }
867 #endif
868 
869 static int lp_register(int nr, struct parport *port)
870 {
871 	lp_table[nr].dev = parport_register_device(port, "lp",
872 						   lp_preempt, NULL, NULL, 0,
873 						   (void *) &lp_table[nr]);
874 	if (lp_table[nr].dev == NULL)
875 		return 1;
876 	lp_table[nr].flags |= LP_EXIST;
877 
878 	if (reset)
879 		lp_reset(nr);
880 
881 	device_create(lp_class, port->dev, MKDEV(LP_MAJOR, nr), NULL,
882 		      "lp%d", nr);
883 
884 	printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name,
885 	       (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
886 
887 #ifdef CONFIG_LP_CONSOLE
888 	if (!nr) {
889 		if (port->modes & PARPORT_MODE_SAFEININT) {
890 			register_console(&lpcons);
891 			console_registered = port;
892 			printk (KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
893 		} else
894 			printk (KERN_ERR "lp%d: cannot run console on %s\n",
895 				CONSOLE_LP, port->name);
896 	}
897 #endif
898 
899 	return 0;
900 }
901 
902 static void lp_attach (struct parport *port)
903 {
904 	unsigned int i;
905 
906 	switch (parport_nr[0]) {
907 	case LP_PARPORT_UNSPEC:
908 	case LP_PARPORT_AUTO:
909 		if (parport_nr[0] == LP_PARPORT_AUTO &&
910 		    port->probe_info[0].class != PARPORT_CLASS_PRINTER)
911 			return;
912 		if (lp_count == LP_NO) {
913 			printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
914 			return;
915 		}
916 		if (!lp_register(lp_count, port))
917 			lp_count++;
918 		break;
919 
920 	default:
921 		for (i = 0; i < LP_NO; i++) {
922 			if (port->number == parport_nr[i]) {
923 				if (!lp_register(i, port))
924 					lp_count++;
925 				break;
926 			}
927 		}
928 		break;
929 	}
930 }
931 
932 static void lp_detach (struct parport *port)
933 {
934 	/* Write this some day. */
935 #ifdef CONFIG_LP_CONSOLE
936 	if (console_registered == port) {
937 		unregister_console(&lpcons);
938 		console_registered = NULL;
939 	}
940 #endif /* CONFIG_LP_CONSOLE */
941 }
942 
943 static struct parport_driver lp_driver = {
944 	.name = "lp",
945 	.attach = lp_attach,
946 	.detach = lp_detach,
947 };
948 
949 static int __init lp_init (void)
950 {
951 	int i, err = 0;
952 
953 	if (parport_nr[0] == LP_PARPORT_OFF)
954 		return 0;
955 
956 	for (i = 0; i < LP_NO; i++) {
957 		lp_table[i].dev = NULL;
958 		lp_table[i].flags = 0;
959 		lp_table[i].chars = LP_INIT_CHAR;
960 		lp_table[i].time = LP_INIT_TIME;
961 		lp_table[i].wait = LP_INIT_WAIT;
962 		lp_table[i].lp_buffer = NULL;
963 #ifdef LP_STATS
964 		lp_table[i].lastcall = 0;
965 		lp_table[i].runchars = 0;
966 		memset (&lp_table[i].stats, 0, sizeof (struct lp_stats));
967 #endif
968 		lp_table[i].last_error = 0;
969 		init_waitqueue_head (&lp_table[i].waitq);
970 		init_waitqueue_head (&lp_table[i].dataq);
971 		mutex_init(&lp_table[i].port_mutex);
972 		lp_table[i].timeout = 10 * HZ;
973 	}
974 
975 	if (register_chrdev (LP_MAJOR, "lp", &lp_fops)) {
976 		printk (KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
977 		return -EIO;
978 	}
979 
980 	lp_class = class_create(THIS_MODULE, "printer");
981 	if (IS_ERR(lp_class)) {
982 		err = PTR_ERR(lp_class);
983 		goto out_reg;
984 	}
985 
986 	if (parport_register_driver (&lp_driver)) {
987 		printk (KERN_ERR "lp: unable to register with parport\n");
988 		err = -EIO;
989 		goto out_class;
990 	}
991 
992 	if (!lp_count) {
993 		printk (KERN_INFO "lp: driver loaded but no devices found\n");
994 #ifndef CONFIG_PARPORT_1284
995 		if (parport_nr[0] == LP_PARPORT_AUTO)
996 			printk (KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
997 #endif
998 	}
999 
1000 	return 0;
1001 
1002 out_class:
1003 	class_destroy(lp_class);
1004 out_reg:
1005 	unregister_chrdev(LP_MAJOR, "lp");
1006 	return err;
1007 }
1008 
1009 static int __init lp_init_module (void)
1010 {
1011 	if (parport[0]) {
1012 		/* The user gave some parameters.  Let's see what they were.  */
1013 		if (!strncmp(parport[0], "auto", 4))
1014 			parport_nr[0] = LP_PARPORT_AUTO;
1015 		else {
1016 			int n;
1017 			for (n = 0; n < LP_NO && parport[n]; n++) {
1018 				if (!strncmp(parport[n], "none", 4))
1019 					parport_nr[n] = LP_PARPORT_NONE;
1020 				else {
1021 					char *ep;
1022 					unsigned long r = simple_strtoul(parport[n], &ep, 0);
1023 					if (ep != parport[n])
1024 						parport_nr[n] = r;
1025 					else {
1026 						printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
1027 						return -ENODEV;
1028 					}
1029 				}
1030 			}
1031 		}
1032 	}
1033 
1034 	return lp_init();
1035 }
1036 
1037 static void lp_cleanup_module (void)
1038 {
1039 	unsigned int offset;
1040 
1041 	parport_unregister_driver (&lp_driver);
1042 
1043 #ifdef CONFIG_LP_CONSOLE
1044 	unregister_console (&lpcons);
1045 #endif
1046 
1047 	unregister_chrdev(LP_MAJOR, "lp");
1048 	for (offset = 0; offset < LP_NO; offset++) {
1049 		if (lp_table[offset].dev == NULL)
1050 			continue;
1051 		parport_unregister_device(lp_table[offset].dev);
1052 		device_destroy(lp_class, MKDEV(LP_MAJOR, offset));
1053 	}
1054 	class_destroy(lp_class);
1055 }
1056 
1057 __setup("lp=", lp_setup);
1058 module_init(lp_init_module);
1059 module_exit(lp_cleanup_module);
1060 
1061 MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
1062 MODULE_LICENSE("GPL");
1063