xref: /linux/drivers/char/lp.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
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/smp_lock.h>
122 #include <linux/slab.h>
123 #include <linux/fcntl.h>
124 #include <linux/delay.h>
125 #include <linux/poll.h>
126 #include <linux/console.h>
127 #include <linux/device.h>
128 #include <linux/wait.h>
129 #include <linux/jiffies.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 /* ROUND_UP macro from fs/select.c */
143 #define ROUND_UP(x,y) (((x)+(y)-1)/(y))
144 
145 static struct lp_struct lp_table[LP_NO];
146 
147 static unsigned int lp_count = 0;
148 static struct class *lp_class;
149 
150 #ifdef CONFIG_LP_CONSOLE
151 static struct parport *console_registered; // initially NULL
152 #endif /* CONFIG_LP_CONSOLE */
153 
154 #undef LP_DEBUG
155 
156 /* Bits used to manage claiming the parport device */
157 #define LP_PREEMPT_REQUEST 1
158 #define LP_PARPORT_CLAIMED 2
159 
160 /* --- low-level port access ----------------------------------- */
161 
162 #define r_dtr(x)	(parport_read_data(lp_table[(x)].dev->port))
163 #define r_str(x)	(parport_read_status(lp_table[(x)].dev->port))
164 #define w_ctr(x,y)	do { parport_write_control(lp_table[(x)].dev->port, (y)); } while (0)
165 #define w_dtr(x,y)	do { parport_write_data(lp_table[(x)].dev->port, (y)); } while (0)
166 
167 /* Claim the parport or block trying unless we've already claimed it */
168 static void lp_claim_parport_or_block(struct lp_struct *this_lp)
169 {
170 	if (!test_and_set_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
171 		parport_claim_or_block (this_lp->dev);
172 	}
173 }
174 
175 /* Claim the parport or block trying unless we've already claimed it */
176 static void lp_release_parport(struct lp_struct *this_lp)
177 {
178 	if (test_and_clear_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
179 		parport_release (this_lp->dev);
180 	}
181 }
182 
183 
184 
185 static int lp_preempt(void *handle)
186 {
187 	struct lp_struct *this_lp = (struct lp_struct *)handle;
188 	set_bit(LP_PREEMPT_REQUEST, &this_lp->bits);
189 	return (1);
190 }
191 
192 
193 /*
194  * Try to negotiate to a new mode; if unsuccessful negotiate to
195  * compatibility mode.  Return the mode we ended up in.
196  */
197 static int lp_negotiate(struct parport * port, int mode)
198 {
199 	if (parport_negotiate (port, mode) != 0) {
200 		mode = IEEE1284_MODE_COMPAT;
201 		parport_negotiate (port, mode);
202 	}
203 
204 	return (mode);
205 }
206 
207 static int lp_reset(int minor)
208 {
209 	int retval;
210 	lp_claim_parport_or_block (&lp_table[minor]);
211 	w_ctr(minor, LP_PSELECP);
212 	udelay (LP_DELAY);
213 	w_ctr(minor, LP_PSELECP | LP_PINITP);
214 	retval = r_str(minor);
215 	lp_release_parport (&lp_table[minor]);
216 	return retval;
217 }
218 
219 static void lp_error (int minor)
220 {
221 	DEFINE_WAIT(wait);
222 	int polling;
223 
224 	if (LP_F(minor) & LP_ABORT)
225 		return;
226 
227 	polling = lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE;
228 	if (polling) lp_release_parport (&lp_table[minor]);
229 	prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
230 	schedule_timeout(LP_TIMEOUT_POLLED);
231 	finish_wait(&lp_table[minor].waitq, &wait);
232 	if (polling) lp_claim_parport_or_block (&lp_table[minor]);
233 	else parport_yield_blocking (lp_table[minor].dev);
234 }
235 
236 static int lp_check_status(int minor)
237 {
238 	int error = 0;
239 	unsigned int last = lp_table[minor].last_error;
240 	unsigned char status = r_str(minor);
241 	if ((status & LP_PERRORP) && !(LP_F(minor) & LP_CAREFUL))
242 		/* No error. */
243 		last = 0;
244 	else if ((status & LP_POUTPA)) {
245 		if (last != LP_POUTPA) {
246 			last = LP_POUTPA;
247 			printk(KERN_INFO "lp%d out of paper\n", minor);
248 		}
249 		error = -ENOSPC;
250 	} else if (!(status & LP_PSELECD)) {
251 		if (last != LP_PSELECD) {
252 			last = LP_PSELECD;
253 			printk(KERN_INFO "lp%d off-line\n", minor);
254 		}
255 		error = -EIO;
256 	} else if (!(status & LP_PERRORP)) {
257 		if (last != LP_PERRORP) {
258 			last = LP_PERRORP;
259 			printk(KERN_INFO "lp%d on fire\n", minor);
260 		}
261 		error = -EIO;
262 	} else {
263 		last = 0; /* Come here if LP_CAREFUL is set and no
264                              errors are reported. */
265 	}
266 
267 	lp_table[minor].last_error = last;
268 
269 	if (last != 0)
270 		lp_error(minor);
271 
272 	return error;
273 }
274 
275 static int lp_wait_ready(int minor, int nonblock)
276 {
277 	int error = 0;
278 
279 	/* If we're not in compatibility mode, we're ready now! */
280 	if (lp_table[minor].current_mode != IEEE1284_MODE_COMPAT) {
281 	  return (0);
282 	}
283 
284 	do {
285 		error = lp_check_status (minor);
286 		if (error && (nonblock || (LP_F(minor) & LP_ABORT)))
287 			break;
288 		if (signal_pending (current)) {
289 			error = -EINTR;
290 			break;
291 		}
292 	} while (error);
293 	return error;
294 }
295 
296 static ssize_t lp_write(struct file * file, const char __user * buf,
297 		        size_t count, loff_t *ppos)
298 {
299 	unsigned int minor = iminor(file->f_dentry->d_inode);
300 	struct parport *port = lp_table[minor].dev->port;
301 	char *kbuf = lp_table[minor].lp_buffer;
302 	ssize_t retv = 0;
303 	ssize_t written;
304 	size_t copy_size = count;
305 	int nonblock = ((file->f_flags & O_NONBLOCK) ||
306 			(LP_F(minor) & LP_ABORT));
307 
308 #ifdef LP_STATS
309 	if (time_after(jiffies, lp_table[minor].lastcall + LP_TIME(minor)))
310 		lp_table[minor].runchars = 0;
311 
312 	lp_table[minor].lastcall = jiffies;
313 #endif
314 
315 	/* Need to copy the data from user-space. */
316 	if (copy_size > LP_BUFFER_SIZE)
317 		copy_size = LP_BUFFER_SIZE;
318 
319 	if (down_interruptible (&lp_table[minor].port_mutex))
320 		return -EINTR;
321 
322 	if (copy_from_user (kbuf, buf, copy_size)) {
323 		retv = -EFAULT;
324 		goto out_unlock;
325 	}
326 
327  	/* Claim Parport or sleep until it becomes available
328  	 */
329 	lp_claim_parport_or_block (&lp_table[minor]);
330 	/* Go to the proper mode. */
331 	lp_table[minor].current_mode = lp_negotiate (port,
332 						     lp_table[minor].best_mode);
333 
334 	parport_set_timeout (lp_table[minor].dev,
335 			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
336 			      : lp_table[minor].timeout));
337 
338 	if ((retv = lp_wait_ready (minor, nonblock)) == 0)
339 	do {
340 		/* Write the data. */
341 		written = parport_write (port, kbuf, copy_size);
342 		if (written > 0) {
343 			copy_size -= written;
344 			count -= written;
345 			buf  += written;
346 			retv += written;
347 		}
348 
349 		if (signal_pending (current)) {
350 			if (retv == 0)
351 				retv = -EINTR;
352 
353 			break;
354 		}
355 
356 		if (copy_size > 0) {
357 			/* incomplete write -> check error ! */
358 			int error;
359 
360 			parport_negotiate (lp_table[minor].dev->port,
361 					   IEEE1284_MODE_COMPAT);
362 			lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
363 
364 			error = lp_wait_ready (minor, nonblock);
365 
366 			if (error) {
367 				if (retv == 0)
368 					retv = error;
369 				break;
370 			} else if (nonblock) {
371 				if (retv == 0)
372 					retv = -EAGAIN;
373 				break;
374 			}
375 
376 			parport_yield_blocking (lp_table[minor].dev);
377 			lp_table[minor].current_mode
378 			  = lp_negotiate (port,
379 					  lp_table[minor].best_mode);
380 
381 		} else if (need_resched())
382 			schedule ();
383 
384 		if (count) {
385 			copy_size = count;
386 			if (copy_size > LP_BUFFER_SIZE)
387 				copy_size = LP_BUFFER_SIZE;
388 
389 			if (copy_from_user(kbuf, buf, copy_size)) {
390 				if (retv == 0)
391 					retv = -EFAULT;
392 				break;
393 			}
394 		}
395 	} while (count > 0);
396 
397 	if (test_and_clear_bit(LP_PREEMPT_REQUEST,
398 			       &lp_table[minor].bits)) {
399 		printk(KERN_INFO "lp%d releasing parport\n", minor);
400 		parport_negotiate (lp_table[minor].dev->port,
401 				   IEEE1284_MODE_COMPAT);
402 		lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
403 		lp_release_parport (&lp_table[minor]);
404 	}
405 out_unlock:
406 	up (&lp_table[minor].port_mutex);
407 
408  	return retv;
409 }
410 
411 #ifdef CONFIG_PARPORT_1284
412 
413 /* Status readback conforming to ieee1284 */
414 static ssize_t lp_read(struct file * file, char __user * buf,
415 		       size_t count, loff_t *ppos)
416 {
417 	DEFINE_WAIT(wait);
418 	unsigned int minor=iminor(file->f_dentry->d_inode);
419 	struct parport *port = lp_table[minor].dev->port;
420 	ssize_t retval = 0;
421 	char *kbuf = lp_table[minor].lp_buffer;
422 	int nonblock = ((file->f_flags & O_NONBLOCK) ||
423 			(LP_F(minor) & LP_ABORT));
424 
425 	if (count > LP_BUFFER_SIZE)
426 		count = LP_BUFFER_SIZE;
427 
428 	if (down_interruptible (&lp_table[minor].port_mutex))
429 		return -EINTR;
430 
431 	lp_claim_parport_or_block (&lp_table[minor]);
432 
433 	parport_set_timeout (lp_table[minor].dev,
434 			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
435 			      : lp_table[minor].timeout));
436 
437 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
438 	if (parport_negotiate (lp_table[minor].dev->port,
439 			       IEEE1284_MODE_NIBBLE)) {
440 		retval = -EIO;
441 		goto out;
442 	}
443 
444 	while (retval == 0) {
445 		retval = parport_read (port, kbuf, count);
446 
447 		if (retval > 0)
448 			break;
449 
450 		if (nonblock) {
451 			retval = -EAGAIN;
452 			break;
453 		}
454 
455 		/* Wait for data. */
456 
457 		if (lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE) {
458 			parport_negotiate (lp_table[minor].dev->port,
459 					   IEEE1284_MODE_COMPAT);
460 			lp_error (minor);
461 			if (parport_negotiate (lp_table[minor].dev->port,
462 					       IEEE1284_MODE_NIBBLE)) {
463 				retval = -EIO;
464 				goto out;
465 			}
466 		} else {
467 			prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
468 			schedule_timeout(LP_TIMEOUT_POLLED);
469 			finish_wait(&lp_table[minor].waitq, &wait);
470 		}
471 
472 		if (signal_pending (current)) {
473 			retval = -ERESTARTSYS;
474 			break;
475 		}
476 
477 		cond_resched ();
478 	}
479 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
480  out:
481 	lp_release_parport (&lp_table[minor]);
482 
483 	if (retval > 0 && copy_to_user (buf, kbuf, retval))
484 		retval = -EFAULT;
485 
486 	up (&lp_table[minor].port_mutex);
487 
488 	return retval;
489 }
490 
491 #endif /* IEEE 1284 support */
492 
493 static int lp_open(struct inode * inode, struct file * file)
494 {
495 	unsigned int minor = iminor(inode);
496 
497 	if (minor >= LP_NO)
498 		return -ENXIO;
499 	if ((LP_F(minor) & LP_EXIST) == 0)
500 		return -ENXIO;
501 	if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor)))
502 		return -EBUSY;
503 
504 	/* If ABORTOPEN is set and the printer is offline or out of paper,
505 	   we may still want to open it to perform ioctl()s.  Therefore we
506 	   have commandeered O_NONBLOCK, even though it is being used in
507 	   a non-standard manner.  This is strictly a Linux hack, and
508 	   should most likely only ever be used by the tunelp application. */
509 	if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
510 		int status;
511 		lp_claim_parport_or_block (&lp_table[minor]);
512 		status = r_str(minor);
513 		lp_release_parport (&lp_table[minor]);
514 		if (status & LP_POUTPA) {
515 			printk(KERN_INFO "lp%d out of paper\n", minor);
516 			LP_F(minor) &= ~LP_BUSY;
517 			return -ENOSPC;
518 		} else if (!(status & LP_PSELECD)) {
519 			printk(KERN_INFO "lp%d off-line\n", minor);
520 			LP_F(minor) &= ~LP_BUSY;
521 			return -EIO;
522 		} else if (!(status & LP_PERRORP)) {
523 			printk(KERN_ERR "lp%d printer error\n", minor);
524 			LP_F(minor) &= ~LP_BUSY;
525 			return -EIO;
526 		}
527 	}
528 	lp_table[minor].lp_buffer = (char *) kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
529 	if (!lp_table[minor].lp_buffer) {
530 		LP_F(minor) &= ~LP_BUSY;
531 		return -ENOMEM;
532 	}
533 	/* Determine if the peripheral supports ECP mode */
534 	lp_claim_parport_or_block (&lp_table[minor]);
535 	if ( (lp_table[minor].dev->port->modes & PARPORT_MODE_ECP) &&
536              !parport_negotiate (lp_table[minor].dev->port,
537                                  IEEE1284_MODE_ECP)) {
538 		printk (KERN_INFO "lp%d: ECP mode\n", minor);
539 		lp_table[minor].best_mode = IEEE1284_MODE_ECP;
540 	} else {
541 		lp_table[minor].best_mode = IEEE1284_MODE_COMPAT;
542 	}
543 	/* Leave peripheral in compatibility mode */
544 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
545 	lp_release_parport (&lp_table[minor]);
546 	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
547 	return 0;
548 }
549 
550 static int lp_release(struct inode * inode, struct file * file)
551 {
552 	unsigned int minor = iminor(inode);
553 
554 	lp_claim_parport_or_block (&lp_table[minor]);
555 	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
556 	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
557 	lp_release_parport (&lp_table[minor]);
558 	kfree(lp_table[minor].lp_buffer);
559 	lp_table[minor].lp_buffer = NULL;
560 	LP_F(minor) &= ~LP_BUSY;
561 	return 0;
562 }
563 
564 static int lp_ioctl(struct inode *inode, struct file *file,
565 		    unsigned int cmd, unsigned long arg)
566 {
567 	unsigned int minor = iminor(inode);
568 	int status;
569 	int retval = 0;
570 	void __user *argp = (void __user *)arg;
571 
572 #ifdef LP_DEBUG
573 	printk(KERN_DEBUG "lp%d ioctl, cmd: 0x%x, arg: 0x%lx\n", minor, cmd, arg);
574 #endif
575 	if (minor >= LP_NO)
576 		return -ENODEV;
577 	if ((LP_F(minor) & LP_EXIST) == 0)
578 		return -ENODEV;
579 	switch ( cmd ) {
580 		struct timeval par_timeout;
581 		long to_jiffies;
582 
583 		case LPTIME:
584 			LP_TIME(minor) = arg * HZ/100;
585 			break;
586 		case LPCHAR:
587 			LP_CHAR(minor) = arg;
588 			break;
589 		case LPABORT:
590 			if (arg)
591 				LP_F(minor) |= LP_ABORT;
592 			else
593 				LP_F(minor) &= ~LP_ABORT;
594 			break;
595 		case LPABORTOPEN:
596 			if (arg)
597 				LP_F(minor) |= LP_ABORTOPEN;
598 			else
599 				LP_F(minor) &= ~LP_ABORTOPEN;
600 			break;
601 		case LPCAREFUL:
602 			if (arg)
603 				LP_F(minor) |= LP_CAREFUL;
604 			else
605 				LP_F(minor) &= ~LP_CAREFUL;
606 			break;
607 		case LPWAIT:
608 			LP_WAIT(minor) = arg;
609 			break;
610 		case LPSETIRQ:
611 			return -EINVAL;
612 			break;
613 		case LPGETIRQ:
614 			if (copy_to_user(argp, &LP_IRQ(minor),
615 					sizeof(int)))
616 				return -EFAULT;
617 			break;
618 		case LPGETSTATUS:
619 			lp_claim_parport_or_block (&lp_table[minor]);
620 			status = r_str(minor);
621 			lp_release_parport (&lp_table[minor]);
622 
623 			if (copy_to_user(argp, &status, sizeof(int)))
624 				return -EFAULT;
625 			break;
626 		case LPRESET:
627 			lp_reset(minor);
628 			break;
629 #ifdef LP_STATS
630 		case LPGETSTATS:
631 			if (copy_to_user(argp, &LP_STAT(minor),
632 					sizeof(struct lp_stats)))
633 				return -EFAULT;
634 			if (capable(CAP_SYS_ADMIN))
635 				memset(&LP_STAT(minor), 0,
636 						sizeof(struct lp_stats));
637 			break;
638 #endif
639  		case LPGETFLAGS:
640  			status = LP_F(minor);
641 			if (copy_to_user(argp, &status, sizeof(int)))
642 				return -EFAULT;
643 			break;
644 
645 		case LPSETTIMEOUT:
646 			if (copy_from_user (&par_timeout, argp,
647 					    sizeof (struct timeval))) {
648 				return -EFAULT;
649 			}
650 			/* Convert to jiffies, place in lp_table */
651 			if ((par_timeout.tv_sec < 0) ||
652 			    (par_timeout.tv_usec < 0)) {
653 				return -EINVAL;
654 			}
655 			to_jiffies = ROUND_UP(par_timeout.tv_usec, 1000000/HZ);
656 			to_jiffies += par_timeout.tv_sec * (long) HZ;
657 			if (to_jiffies <= 0) {
658 				return -EINVAL;
659 			}
660 			lp_table[minor].timeout = to_jiffies;
661 			break;
662 
663 		default:
664 			retval = -EINVAL;
665 	}
666 	return retval;
667 }
668 
669 static const struct file_operations lp_fops = {
670 	.owner		= THIS_MODULE,
671 	.write		= lp_write,
672 	.ioctl		= lp_ioctl,
673 	.open		= lp_open,
674 	.release	= lp_release,
675 #ifdef CONFIG_PARPORT_1284
676 	.read		= lp_read,
677 #endif
678 };
679 
680 /* --- support for console on the line printer ----------------- */
681 
682 #ifdef CONFIG_LP_CONSOLE
683 
684 #define CONSOLE_LP 0
685 
686 /* If the printer is out of paper, we can either lose the messages or
687  * stall until the printer is happy again.  Define CONSOLE_LP_STRICT
688  * non-zero to get the latter behaviour. */
689 #define CONSOLE_LP_STRICT 1
690 
691 /* The console must be locked when we get here. */
692 
693 static void lp_console_write (struct console *co, const char *s,
694 			      unsigned count)
695 {
696 	struct pardevice *dev = lp_table[CONSOLE_LP].dev;
697 	struct parport *port = dev->port;
698 	ssize_t written;
699 
700 	if (parport_claim (dev))
701 		/* Nothing we can do. */
702 		return;
703 
704 	parport_set_timeout (dev, 0);
705 
706 	/* Go to compatibility mode. */
707 	parport_negotiate (port, IEEE1284_MODE_COMPAT);
708 
709 	do {
710 		/* Write the data, converting LF->CRLF as we go. */
711 		ssize_t canwrite = count;
712 		char *lf = memchr (s, '\n', count);
713 		if (lf)
714 			canwrite = lf - s;
715 
716 		if (canwrite > 0) {
717 			written = parport_write (port, s, canwrite);
718 
719 			if (written <= 0)
720 				continue;
721 
722 			s += written;
723 			count -= written;
724 			canwrite -= written;
725 		}
726 
727 		if (lf && canwrite <= 0) {
728 			const char *crlf = "\r\n";
729 			int i = 2;
730 
731 			/* Dodge the original '\n', and put '\r\n' instead. */
732 			s++;
733 			count--;
734 			do {
735 				written = parport_write (port, crlf, i);
736 				if (written > 0)
737 					i -= written, crlf += written;
738 			} while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
739 		}
740 	} while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
741 
742 	parport_release (dev);
743 }
744 
745 static struct console lpcons = {
746 	.name		= "lp",
747 	.write		= lp_console_write,
748 	.flags		= CON_PRINTBUFFER,
749 };
750 
751 #endif /* console on line printer */
752 
753 /* --- initialisation code ------------------------------------- */
754 
755 static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
756 static char *parport[LP_NO] = { NULL,  };
757 static int reset = 0;
758 
759 module_param_array(parport, charp, NULL, 0);
760 module_param(reset, bool, 0);
761 
762 #ifndef MODULE
763 static int __init lp_setup (char *str)
764 {
765 	static int parport_ptr; // initially zero
766 	int x;
767 
768 	if (get_option (&str, &x)) {
769 		if (x == 0) {
770 			/* disable driver on "lp=" or "lp=0" */
771 			parport_nr[0] = LP_PARPORT_OFF;
772 		} else {
773 			printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
774 			return 0;
775 		}
776 	} else if (!strncmp(str, "parport", 7)) {
777 		int n = simple_strtoul(str+7, NULL, 10);
778 		if (parport_ptr < LP_NO)
779 			parport_nr[parport_ptr++] = n;
780 		else
781 			printk(KERN_INFO "lp: too many ports, %s ignored.\n",
782 			       str);
783 	} else if (!strcmp(str, "auto")) {
784 		parport_nr[0] = LP_PARPORT_AUTO;
785 	} else if (!strcmp(str, "none")) {
786 		parport_nr[parport_ptr++] = LP_PARPORT_NONE;
787 	} else if (!strcmp(str, "reset")) {
788 		reset = 1;
789 	}
790 	return 1;
791 }
792 #endif
793 
794 static int lp_register(int nr, struct parport *port)
795 {
796 	lp_table[nr].dev = parport_register_device(port, "lp",
797 						   lp_preempt, NULL, NULL, 0,
798 						   (void *) &lp_table[nr]);
799 	if (lp_table[nr].dev == NULL)
800 		return 1;
801 	lp_table[nr].flags |= LP_EXIST;
802 
803 	if (reset)
804 		lp_reset(nr);
805 
806 	class_device_create(lp_class, NULL, MKDEV(LP_MAJOR, nr), NULL,
807 				"lp%d", nr);
808 
809 	printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name,
810 	       (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
811 
812 #ifdef CONFIG_LP_CONSOLE
813 	if (!nr) {
814 		if (port->modes & PARPORT_MODE_SAFEININT) {
815 			register_console (&lpcons);
816 			console_registered = port;
817 			printk (KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
818 		} else
819 			printk (KERN_ERR "lp%d: cannot run console on %s\n",
820 				CONSOLE_LP, port->name);
821 	}
822 #endif
823 
824 	return 0;
825 }
826 
827 static void lp_attach (struct parport *port)
828 {
829 	unsigned int i;
830 
831 	switch (parport_nr[0])
832 	{
833 	case LP_PARPORT_UNSPEC:
834 	case LP_PARPORT_AUTO:
835 		if (parport_nr[0] == LP_PARPORT_AUTO &&
836 		    port->probe_info[0].class != PARPORT_CLASS_PRINTER)
837 			return;
838 		if (lp_count == LP_NO) {
839 			printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
840 			return;
841 		}
842 		if (!lp_register(lp_count, port))
843 			lp_count++;
844 		break;
845 
846 	default:
847 		for (i = 0; i < LP_NO; i++) {
848 			if (port->number == parport_nr[i]) {
849 				if (!lp_register(i, port))
850 					lp_count++;
851 				break;
852 			}
853 		}
854 		break;
855 	}
856 }
857 
858 static void lp_detach (struct parport *port)
859 {
860 	/* Write this some day. */
861 #ifdef CONFIG_LP_CONSOLE
862 	if (console_registered == port) {
863 		unregister_console (&lpcons);
864 		console_registered = NULL;
865 	}
866 #endif /* CONFIG_LP_CONSOLE */
867 }
868 
869 static struct parport_driver lp_driver = {
870 	.name = "lp",
871 	.attach = lp_attach,
872 	.detach = lp_detach,
873 };
874 
875 static int __init lp_init (void)
876 {
877 	int i, err = 0;
878 
879 	if (parport_nr[0] == LP_PARPORT_OFF)
880 		return 0;
881 
882 	for (i = 0; i < LP_NO; i++) {
883 		lp_table[i].dev = NULL;
884 		lp_table[i].flags = 0;
885 		lp_table[i].chars = LP_INIT_CHAR;
886 		lp_table[i].time = LP_INIT_TIME;
887 		lp_table[i].wait = LP_INIT_WAIT;
888 		lp_table[i].lp_buffer = NULL;
889 #ifdef LP_STATS
890 		lp_table[i].lastcall = 0;
891 		lp_table[i].runchars = 0;
892 		memset (&lp_table[i].stats, 0, sizeof (struct lp_stats));
893 #endif
894 		lp_table[i].last_error = 0;
895 		init_waitqueue_head (&lp_table[i].waitq);
896 		init_waitqueue_head (&lp_table[i].dataq);
897 		init_MUTEX (&lp_table[i].port_mutex);
898 		lp_table[i].timeout = 10 * HZ;
899 	}
900 
901 	if (register_chrdev (LP_MAJOR, "lp", &lp_fops)) {
902 		printk (KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
903 		return -EIO;
904 	}
905 
906 	lp_class = class_create(THIS_MODULE, "printer");
907 	if (IS_ERR(lp_class)) {
908 		err = PTR_ERR(lp_class);
909 		goto out_devfs;
910 	}
911 
912 	if (parport_register_driver (&lp_driver)) {
913 		printk (KERN_ERR "lp: unable to register with parport\n");
914 		err = -EIO;
915 		goto out_class;
916 	}
917 
918 	if (!lp_count) {
919 		printk (KERN_INFO "lp: driver loaded but no devices found\n");
920 #ifndef CONFIG_PARPORT_1284
921 		if (parport_nr[0] == LP_PARPORT_AUTO)
922 			printk (KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
923 #endif
924 	}
925 
926 	return 0;
927 
928 out_class:
929 	class_destroy(lp_class);
930 out_devfs:
931 	unregister_chrdev(LP_MAJOR, "lp");
932 	return err;
933 }
934 
935 static int __init lp_init_module (void)
936 {
937 	if (parport[0]) {
938 		/* The user gave some parameters.  Let's see what they were.  */
939 		if (!strncmp(parport[0], "auto", 4))
940 			parport_nr[0] = LP_PARPORT_AUTO;
941 		else {
942 			int n;
943 			for (n = 0; n < LP_NO && parport[n]; n++) {
944 				if (!strncmp(parport[n], "none", 4))
945 					parport_nr[n] = LP_PARPORT_NONE;
946 				else {
947 					char *ep;
948 					unsigned long r = simple_strtoul(parport[n], &ep, 0);
949 					if (ep != parport[n])
950 						parport_nr[n] = r;
951 					else {
952 						printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
953 						return -ENODEV;
954 					}
955 				}
956 			}
957 		}
958 	}
959 
960 	return lp_init();
961 }
962 
963 static void lp_cleanup_module (void)
964 {
965 	unsigned int offset;
966 
967 	parport_unregister_driver (&lp_driver);
968 
969 #ifdef CONFIG_LP_CONSOLE
970 	unregister_console (&lpcons);
971 #endif
972 
973 	unregister_chrdev(LP_MAJOR, "lp");
974 	for (offset = 0; offset < LP_NO; offset++) {
975 		if (lp_table[offset].dev == NULL)
976 			continue;
977 		parport_unregister_device(lp_table[offset].dev);
978 		class_device_destroy(lp_class, MKDEV(LP_MAJOR, offset));
979 	}
980 	class_destroy(lp_class);
981 }
982 
983 __setup("lp=", lp_setup);
984 module_init(lp_init_module);
985 module_exit(lp_cleanup_module);
986 
987 MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
988 MODULE_LICENSE("GPL");
989