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
139/* if you have more than 8 printers, remember to increase LP_NO */
140#define LP_NO 8
141
142static DEFINE_MUTEX(lp_mutex);
143static struct lp_struct lp_table[LP_NO];
144
145static unsigned int lp_count = 0;
146static struct class *lp_class;
147
148#ifdef CONFIG_LP_CONSOLE
149static struct parport *console_registered;
150#endif /* CONFIG_LP_CONSOLE */
151
152#undef LP_DEBUG
153
154/* Bits used to manage claiming the parport device */
155#define LP_PREEMPT_REQUEST 1
156#define LP_PARPORT_CLAIMED 2
157
158/* --- low-level port access ----------------------------------- */
159
160#define r_dtr(x)	(parport_read_data(lp_table[(x)].dev->port))
161#define r_str(x)	(parport_read_status(lp_table[(x)].dev->port))
162#define w_ctr(x,y)	do { parport_write_control(lp_table[(x)].dev->port, (y)); } while (0)
163#define w_dtr(x,y)	do { parport_write_data(lp_table[(x)].dev->port, (y)); } while (0)
164
165/* Claim the parport or block trying unless we've already claimed it */
166static void lp_claim_parport_or_block(struct lp_struct *this_lp)
167{
168	if (!test_and_set_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
169		parport_claim_or_block (this_lp->dev);
170	}
171}
172
173/* Claim the parport or block trying unless we've already claimed it */
174static void lp_release_parport(struct lp_struct *this_lp)
175{
176	if (test_and_clear_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
177		parport_release (this_lp->dev);
178	}
179}
180
181
182
183static int lp_preempt(void *handle)
184{
185	struct lp_struct *this_lp = (struct lp_struct *)handle;
186	set_bit(LP_PREEMPT_REQUEST, &this_lp->bits);
187	return (1);
188}
189
190
191/*
192 * Try to negotiate to a new mode; if unsuccessful negotiate to
193 * compatibility mode.  Return the mode we ended up in.
194 */
195static int lp_negotiate(struct parport * port, int mode)
196{
197	if (parport_negotiate (port, mode) != 0) {
198		mode = IEEE1284_MODE_COMPAT;
199		parport_negotiate (port, mode);
200	}
201
202	return (mode);
203}
204
205static int lp_reset(int minor)
206{
207	int retval;
208	lp_claim_parport_or_block (&lp_table[minor]);
209	w_ctr(minor, LP_PSELECP);
210	udelay (LP_DELAY);
211	w_ctr(minor, LP_PSELECP | LP_PINITP);
212	retval = r_str(minor);
213	lp_release_parport (&lp_table[minor]);
214	return retval;
215}
216
217static void lp_error (int minor)
218{
219	DEFINE_WAIT(wait);
220	int polling;
221
222	if (LP_F(minor) & LP_ABORT)
223		return;
224
225	polling = lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE;
226	if (polling) lp_release_parport (&lp_table[minor]);
227	prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
228	schedule_timeout(LP_TIMEOUT_POLLED);
229	finish_wait(&lp_table[minor].waitq, &wait);
230	if (polling) lp_claim_parport_or_block (&lp_table[minor]);
231	else parport_yield_blocking (lp_table[minor].dev);
232}
233
234static int lp_check_status(int minor)
235{
236	int error = 0;
237	unsigned int last = lp_table[minor].last_error;
238	unsigned char status = r_str(minor);
239	if ((status & LP_PERRORP) && !(LP_F(minor) & LP_CAREFUL))
240		/* No error. */
241		last = 0;
242	else if ((status & LP_POUTPA)) {
243		if (last != LP_POUTPA) {
244			last = LP_POUTPA;
245			printk(KERN_INFO "lp%d out of paper\n", minor);
246		}
247		error = -ENOSPC;
248	} else if (!(status & LP_PSELECD)) {
249		if (last != LP_PSELECD) {
250			last = LP_PSELECD;
251			printk(KERN_INFO "lp%d off-line\n", minor);
252		}
253		error = -EIO;
254	} else if (!(status & LP_PERRORP)) {
255		if (last != LP_PERRORP) {
256			last = LP_PERRORP;
257			printk(KERN_INFO "lp%d on fire\n", minor);
258		}
259		error = -EIO;
260	} else {
261		last = 0; /* Come here if LP_CAREFUL is set and no
262                             errors are reported. */
263	}
264
265	lp_table[minor].last_error = last;
266
267	if (last != 0)
268		lp_error(minor);
269
270	return error;
271}
272
273static int lp_wait_ready(int minor, int nonblock)
274{
275	int error = 0;
276
277	/* If we're not in compatibility mode, we're ready now! */
278	if (lp_table[minor].current_mode != IEEE1284_MODE_COMPAT) {
279	  return (0);
280	}
281
282	do {
283		error = lp_check_status (minor);
284		if (error && (nonblock || (LP_F(minor) & LP_ABORT)))
285			break;
286		if (signal_pending (current)) {
287			error = -EINTR;
288			break;
289		}
290	} while (error);
291	return error;
292}
293
294static ssize_t lp_write(struct file * file, const char __user * buf,
295		        size_t count, loff_t *ppos)
296{
297	unsigned int minor = iminor(file_inode(file));
298	struct parport *port = lp_table[minor].dev->port;
299	char *kbuf = lp_table[minor].lp_buffer;
300	ssize_t retv = 0;
301	ssize_t written;
302	size_t copy_size = count;
303	int nonblock = ((file->f_flags & O_NONBLOCK) ||
304			(LP_F(minor) & LP_ABORT));
305
306#ifdef LP_STATS
307	if (time_after(jiffies, lp_table[minor].lastcall + LP_TIME(minor)))
308		lp_table[minor].runchars = 0;
309
310	lp_table[minor].lastcall = jiffies;
311#endif
312
313	/* Need to copy the data from user-space. */
314	if (copy_size > LP_BUFFER_SIZE)
315		copy_size = LP_BUFFER_SIZE;
316
317	if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
318		return -EINTR;
319
320	if (copy_from_user (kbuf, buf, copy_size)) {
321		retv = -EFAULT;
322		goto out_unlock;
323	}
324
325 	/* Claim Parport or sleep until it becomes available
326 	 */
327	lp_claim_parport_or_block (&lp_table[minor]);
328	/* Go to the proper mode. */
329	lp_table[minor].current_mode = lp_negotiate (port,
330						     lp_table[minor].best_mode);
331
332	parport_set_timeout (lp_table[minor].dev,
333			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
334			      : lp_table[minor].timeout));
335
336	if ((retv = lp_wait_ready (minor, nonblock)) == 0)
337	do {
338		/* Write the data. */
339		written = parport_write (port, kbuf, copy_size);
340		if (written > 0) {
341			copy_size -= written;
342			count -= written;
343			buf  += written;
344			retv += written;
345		}
346
347		if (signal_pending (current)) {
348			if (retv == 0)
349				retv = -EINTR;
350
351			break;
352		}
353
354		if (copy_size > 0) {
355			/* incomplete write -> check error ! */
356			int error;
357
358			parport_negotiate (lp_table[minor].dev->port,
359					   IEEE1284_MODE_COMPAT);
360			lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
361
362			error = lp_wait_ready (minor, nonblock);
363
364			if (error) {
365				if (retv == 0)
366					retv = error;
367				break;
368			} else if (nonblock) {
369				if (retv == 0)
370					retv = -EAGAIN;
371				break;
372			}
373
374			parport_yield_blocking (lp_table[minor].dev);
375			lp_table[minor].current_mode
376			  = lp_negotiate (port,
377					  lp_table[minor].best_mode);
378
379		} else if (need_resched())
380			schedule ();
381
382		if (count) {
383			copy_size = count;
384			if (copy_size > LP_BUFFER_SIZE)
385				copy_size = LP_BUFFER_SIZE;
386
387			if (copy_from_user(kbuf, buf, copy_size)) {
388				if (retv == 0)
389					retv = -EFAULT;
390				break;
391			}
392		}
393	} while (count > 0);
394
395	if (test_and_clear_bit(LP_PREEMPT_REQUEST,
396			       &lp_table[minor].bits)) {
397		printk(KERN_INFO "lp%d releasing parport\n", minor);
398		parport_negotiate (lp_table[minor].dev->port,
399				   IEEE1284_MODE_COMPAT);
400		lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
401		lp_release_parport (&lp_table[minor]);
402	}
403out_unlock:
404	mutex_unlock(&lp_table[minor].port_mutex);
405
406 	return retv;
407}
408
409#ifdef CONFIG_PARPORT_1284
410
411/* Status readback conforming to ieee1284 */
412static ssize_t lp_read(struct file * file, char __user * buf,
413		       size_t count, loff_t *ppos)
414{
415	DEFINE_WAIT(wait);
416	unsigned int minor=iminor(file_inode(file));
417	struct parport *port = lp_table[minor].dev->port;
418	ssize_t retval = 0;
419	char *kbuf = lp_table[minor].lp_buffer;
420	int nonblock = ((file->f_flags & O_NONBLOCK) ||
421			(LP_F(minor) & LP_ABORT));
422
423	if (count > LP_BUFFER_SIZE)
424		count = LP_BUFFER_SIZE;
425
426	if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
427		return -EINTR;
428
429	lp_claim_parport_or_block (&lp_table[minor]);
430
431	parport_set_timeout (lp_table[minor].dev,
432			     (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
433			      : lp_table[minor].timeout));
434
435	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
436	if (parport_negotiate (lp_table[minor].dev->port,
437			       IEEE1284_MODE_NIBBLE)) {
438		retval = -EIO;
439		goto out;
440	}
441
442	while (retval == 0) {
443		retval = parport_read (port, kbuf, count);
444
445		if (retval > 0)
446			break;
447
448		if (nonblock) {
449			retval = -EAGAIN;
450			break;
451		}
452
453		/* Wait for data. */
454
455		if (lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE) {
456			parport_negotiate (lp_table[minor].dev->port,
457					   IEEE1284_MODE_COMPAT);
458			lp_error (minor);
459			if (parport_negotiate (lp_table[minor].dev->port,
460					       IEEE1284_MODE_NIBBLE)) {
461				retval = -EIO;
462				goto out;
463			}
464		} else {
465			prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
466			schedule_timeout(LP_TIMEOUT_POLLED);
467			finish_wait(&lp_table[minor].waitq, &wait);
468		}
469
470		if (signal_pending (current)) {
471			retval = -ERESTARTSYS;
472			break;
473		}
474
475		cond_resched ();
476	}
477	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
478 out:
479	lp_release_parport (&lp_table[minor]);
480
481	if (retval > 0 && copy_to_user (buf, kbuf, retval))
482		retval = -EFAULT;
483
484	mutex_unlock(&lp_table[minor].port_mutex);
485
486	return retval;
487}
488
489#endif /* IEEE 1284 support */
490
491static int lp_open(struct inode * inode, struct file * file)
492{
493	unsigned int minor = iminor(inode);
494	int ret = 0;
495
496	mutex_lock(&lp_mutex);
497	if (minor >= LP_NO) {
498		ret = -ENXIO;
499		goto out;
500	}
501	if ((LP_F(minor) & LP_EXIST) == 0) {
502		ret = -ENXIO;
503		goto out;
504	}
505	if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor))) {
506		ret = -EBUSY;
507		goto out;
508	}
509	/* If ABORTOPEN is set and the printer is offline or out of paper,
510	   we may still want to open it to perform ioctl()s.  Therefore we
511	   have commandeered O_NONBLOCK, even though it is being used in
512	   a non-standard manner.  This is strictly a Linux hack, and
513	   should most likely only ever be used by the tunelp application. */
514	if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
515		int status;
516		lp_claim_parport_or_block (&lp_table[minor]);
517		status = r_str(minor);
518		lp_release_parport (&lp_table[minor]);
519		if (status & LP_POUTPA) {
520			printk(KERN_INFO "lp%d out of paper\n", minor);
521			LP_F(minor) &= ~LP_BUSY;
522			ret = -ENOSPC;
523			goto out;
524		} else if (!(status & LP_PSELECD)) {
525			printk(KERN_INFO "lp%d off-line\n", minor);
526			LP_F(minor) &= ~LP_BUSY;
527			ret = -EIO;
528			goto out;
529		} else if (!(status & LP_PERRORP)) {
530			printk(KERN_ERR "lp%d printer error\n", minor);
531			LP_F(minor) &= ~LP_BUSY;
532			ret = -EIO;
533			goto out;
534		}
535	}
536	lp_table[minor].lp_buffer = kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
537	if (!lp_table[minor].lp_buffer) {
538		LP_F(minor) &= ~LP_BUSY;
539		ret = -ENOMEM;
540		goto out;
541	}
542	/* Determine if the peripheral supports ECP mode */
543	lp_claim_parport_or_block (&lp_table[minor]);
544	if ( (lp_table[minor].dev->port->modes & PARPORT_MODE_ECP) &&
545             !parport_negotiate (lp_table[minor].dev->port,
546                                 IEEE1284_MODE_ECP)) {
547		printk (KERN_INFO "lp%d: ECP mode\n", minor);
548		lp_table[minor].best_mode = IEEE1284_MODE_ECP;
549	} else {
550		lp_table[minor].best_mode = IEEE1284_MODE_COMPAT;
551	}
552	/* Leave peripheral in compatibility mode */
553	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
554	lp_release_parport (&lp_table[minor]);
555	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
556out:
557	mutex_unlock(&lp_mutex);
558	return ret;
559}
560
561static int lp_release(struct inode * inode, struct file * file)
562{
563	unsigned int minor = iminor(inode);
564
565	lp_claim_parport_or_block (&lp_table[minor]);
566	parport_negotiate (lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
567	lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
568	lp_release_parport (&lp_table[minor]);
569	kfree(lp_table[minor].lp_buffer);
570	lp_table[minor].lp_buffer = NULL;
571	LP_F(minor) &= ~LP_BUSY;
572	return 0;
573}
574
575static int lp_do_ioctl(unsigned int minor, unsigned int cmd,
576	unsigned long arg, void __user *argp)
577{
578	int status;
579	int retval = 0;
580
581#ifdef LP_DEBUG
582	printk(KERN_DEBUG "lp%d ioctl, cmd: 0x%x, arg: 0x%lx\n", minor, cmd, arg);
583#endif
584	if (minor >= LP_NO)
585		return -ENODEV;
586	if ((LP_F(minor) & LP_EXIST) == 0)
587		return -ENODEV;
588	switch ( cmd ) {
589		case LPTIME:
590			if (arg > UINT_MAX / HZ)
591				return -EINVAL;
592			LP_TIME(minor) = arg * HZ/100;
593			break;
594		case LPCHAR:
595			LP_CHAR(minor) = arg;
596			break;
597		case LPABORT:
598			if (arg)
599				LP_F(minor) |= LP_ABORT;
600			else
601				LP_F(minor) &= ~LP_ABORT;
602			break;
603		case LPABORTOPEN:
604			if (arg)
605				LP_F(minor) |= LP_ABORTOPEN;
606			else
607				LP_F(minor) &= ~LP_ABORTOPEN;
608			break;
609		case LPCAREFUL:
610			if (arg)
611				LP_F(minor) |= LP_CAREFUL;
612			else
613				LP_F(minor) &= ~LP_CAREFUL;
614			break;
615		case LPWAIT:
616			LP_WAIT(minor) = arg;
617			break;
618		case LPSETIRQ:
619			return -EINVAL;
620			break;
621		case LPGETIRQ:
622			if (copy_to_user(argp, &LP_IRQ(minor),
623					sizeof(int)))
624				return -EFAULT;
625			break;
626		case LPGETSTATUS:
627			if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
628				return -EINTR;
629			lp_claim_parport_or_block (&lp_table[minor]);
630			status = r_str(minor);
631			lp_release_parport (&lp_table[minor]);
632			mutex_unlock(&lp_table[minor].port_mutex);
633
634			if (copy_to_user(argp, &status, sizeof(int)))
635				return -EFAULT;
636			break;
637		case LPRESET:
638			lp_reset(minor);
639			break;
640#ifdef LP_STATS
641		case LPGETSTATS:
642			if (copy_to_user(argp, &LP_STAT(minor),
643					sizeof(struct lp_stats)))
644				return -EFAULT;
645			if (capable(CAP_SYS_ADMIN))
646				memset(&LP_STAT(minor), 0,
647						sizeof(struct lp_stats));
648			break;
649#endif
650 		case LPGETFLAGS:
651 			status = LP_F(minor);
652			if (copy_to_user(argp, &status, sizeof(int)))
653				return -EFAULT;
654			break;
655
656		default:
657			retval = -EINVAL;
658	}
659	return retval;
660}
661
662static int lp_set_timeout(unsigned int minor, struct timeval *par_timeout)
663{
664	long to_jiffies;
665
666	/* Convert to jiffies, place in lp_table */
667	if ((par_timeout->tv_sec < 0) ||
668	    (par_timeout->tv_usec < 0)) {
669		return -EINVAL;
670	}
671	to_jiffies = DIV_ROUND_UP(par_timeout->tv_usec, 1000000/HZ);
672	to_jiffies += par_timeout->tv_sec * (long) HZ;
673	if (to_jiffies <= 0) {
674		return -EINVAL;
675	}
676	lp_table[minor].timeout = to_jiffies;
677	return 0;
678}
679
680static long lp_ioctl(struct file *file, unsigned int cmd,
681			unsigned long arg)
682{
683	unsigned int minor;
684	struct timeval par_timeout;
685	int ret;
686
687	minor = iminor(file_inode(file));
688	mutex_lock(&lp_mutex);
689	switch (cmd) {
690	case LPSETTIMEOUT:
691		if (copy_from_user(&par_timeout, (void __user *)arg,
692					sizeof (struct timeval))) {
693			ret = -EFAULT;
694			break;
695		}
696		ret = lp_set_timeout(minor, &par_timeout);
697		break;
698	default:
699		ret = lp_do_ioctl(minor, cmd, arg, (void __user *)arg);
700		break;
701	}
702	mutex_unlock(&lp_mutex);
703
704	return ret;
705}
706
707#ifdef CONFIG_COMPAT
708static long lp_compat_ioctl(struct file *file, unsigned int cmd,
709			unsigned long arg)
710{
711	unsigned int minor;
712	struct timeval par_timeout;
713	int ret;
714
715	minor = iminor(file_inode(file));
716	mutex_lock(&lp_mutex);
717	switch (cmd) {
718	case LPSETTIMEOUT:
719		if (compat_get_timeval(&par_timeout, compat_ptr(arg))) {
720			ret = -EFAULT;
721			break;
722		}
723		ret = lp_set_timeout(minor, &par_timeout);
724		break;
725#ifdef LP_STATS
726	case LPGETSTATS:
727		/* FIXME: add an implementation if you set LP_STATS */
728		ret = -EINVAL;
729		break;
730#endif
731	default:
732		ret = lp_do_ioctl(minor, cmd, arg, compat_ptr(arg));
733		break;
734	}
735	mutex_unlock(&lp_mutex);
736
737	return ret;
738}
739#endif
740
741static const struct file_operations lp_fops = {
742	.owner		= THIS_MODULE,
743	.write		= lp_write,
744	.unlocked_ioctl	= lp_ioctl,
745#ifdef CONFIG_COMPAT
746	.compat_ioctl	= lp_compat_ioctl,
747#endif
748	.open		= lp_open,
749	.release	= lp_release,
750#ifdef CONFIG_PARPORT_1284
751	.read		= lp_read,
752#endif
753	.llseek		= noop_llseek,
754};
755
756/* --- support for console on the line printer ----------------- */
757
758#ifdef CONFIG_LP_CONSOLE
759
760#define CONSOLE_LP 0
761
762/* If the printer is out of paper, we can either lose the messages or
763 * stall until the printer is happy again.  Define CONSOLE_LP_STRICT
764 * non-zero to get the latter behaviour. */
765#define CONSOLE_LP_STRICT 1
766
767/* The console must be locked when we get here. */
768
769static void lp_console_write (struct console *co, const char *s,
770			      unsigned count)
771{
772	struct pardevice *dev = lp_table[CONSOLE_LP].dev;
773	struct parport *port = dev->port;
774	ssize_t written;
775
776	if (parport_claim (dev))
777		/* Nothing we can do. */
778		return;
779
780	parport_set_timeout (dev, 0);
781
782	/* Go to compatibility mode. */
783	parport_negotiate (port, IEEE1284_MODE_COMPAT);
784
785	do {
786		/* Write the data, converting LF->CRLF as we go. */
787		ssize_t canwrite = count;
788		char *lf = memchr (s, '\n', count);
789		if (lf)
790			canwrite = lf - s;
791
792		if (canwrite > 0) {
793			written = parport_write (port, s, canwrite);
794
795			if (written <= 0)
796				continue;
797
798			s += written;
799			count -= written;
800			canwrite -= written;
801		}
802
803		if (lf && canwrite <= 0) {
804			const char *crlf = "\r\n";
805			int i = 2;
806
807			/* Dodge the original '\n', and put '\r\n' instead. */
808			s++;
809			count--;
810			do {
811				written = parport_write (port, crlf, i);
812				if (written > 0)
813					i -= written, crlf += written;
814			} while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
815		}
816	} while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
817
818	parport_release (dev);
819}
820
821static struct console lpcons = {
822	.name		= "lp",
823	.write		= lp_console_write,
824	.flags		= CON_PRINTBUFFER,
825};
826
827#endif /* console on line printer */
828
829/* --- initialisation code ------------------------------------- */
830
831static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
832static char *parport[LP_NO];
833static bool reset;
834
835module_param_array(parport, charp, NULL, 0);
836module_param(reset, bool, 0);
837
838#ifndef MODULE
839static int __init lp_setup (char *str)
840{
841	static int parport_ptr;
842	int x;
843
844	if (get_option(&str, &x)) {
845		if (x == 0) {
846			/* disable driver on "lp=" or "lp=0" */
847			parport_nr[0] = LP_PARPORT_OFF;
848		} else {
849			printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
850			return 0;
851		}
852	} else if (!strncmp(str, "parport", 7)) {
853		int n = simple_strtoul(str+7, NULL, 10);
854		if (parport_ptr < LP_NO)
855			parport_nr[parport_ptr++] = n;
856		else
857			printk(KERN_INFO "lp: too many ports, %s ignored.\n",
858			       str);
859	} else if (!strcmp(str, "auto")) {
860		parport_nr[0] = LP_PARPORT_AUTO;
861	} else if (!strcmp(str, "none")) {
862		parport_nr[parport_ptr++] = LP_PARPORT_NONE;
863	} else if (!strcmp(str, "reset")) {
864		reset = 1;
865	}
866	return 1;
867}
868#endif
869
870static int lp_register(int nr, struct parport *port)
871{
872	lp_table[nr].dev = parport_register_device(port, "lp",
873						   lp_preempt, NULL, NULL, 0,
874						   (void *) &lp_table[nr]);
875	if (lp_table[nr].dev == NULL)
876		return 1;
877	lp_table[nr].flags |= LP_EXIST;
878
879	if (reset)
880		lp_reset(nr);
881
882	device_create(lp_class, port->dev, MKDEV(LP_MAJOR, nr), NULL,
883		      "lp%d", nr);
884
885	printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name,
886	       (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
887
888#ifdef CONFIG_LP_CONSOLE
889	if (!nr) {
890		if (port->modes & PARPORT_MODE_SAFEININT) {
891			register_console(&lpcons);
892			console_registered = port;
893			printk (KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
894		} else
895			printk (KERN_ERR "lp%d: cannot run console on %s\n",
896				CONSOLE_LP, port->name);
897	}
898#endif
899
900	return 0;
901}
902
903static void lp_attach (struct parport *port)
904{
905	unsigned int i;
906
907	switch (parport_nr[0]) {
908	case LP_PARPORT_UNSPEC:
909	case LP_PARPORT_AUTO:
910		if (parport_nr[0] == LP_PARPORT_AUTO &&
911		    port->probe_info[0].class != PARPORT_CLASS_PRINTER)
912			return;
913		if (lp_count == LP_NO) {
914			printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
915			return;
916		}
917		if (!lp_register(lp_count, port))
918			lp_count++;
919		break;
920
921	default:
922		for (i = 0; i < LP_NO; i++) {
923			if (port->number == parport_nr[i]) {
924				if (!lp_register(i, port))
925					lp_count++;
926				break;
927			}
928		}
929		break;
930	}
931}
932
933static void lp_detach (struct parport *port)
934{
935	/* Write this some day. */
936#ifdef CONFIG_LP_CONSOLE
937	if (console_registered == port) {
938		unregister_console(&lpcons);
939		console_registered = NULL;
940	}
941#endif /* CONFIG_LP_CONSOLE */
942}
943
944static struct parport_driver lp_driver = {
945	.name = "lp",
946	.attach = lp_attach,
947	.detach = lp_detach,
948};
949
950static int __init lp_init (void)
951{
952	int i, err = 0;
953
954	if (parport_nr[0] == LP_PARPORT_OFF)
955		return 0;
956
957	for (i = 0; i < LP_NO; i++) {
958		lp_table[i].dev = NULL;
959		lp_table[i].flags = 0;
960		lp_table[i].chars = LP_INIT_CHAR;
961		lp_table[i].time = LP_INIT_TIME;
962		lp_table[i].wait = LP_INIT_WAIT;
963		lp_table[i].lp_buffer = NULL;
964#ifdef LP_STATS
965		lp_table[i].lastcall = 0;
966		lp_table[i].runchars = 0;
967		memset (&lp_table[i].stats, 0, sizeof (struct lp_stats));
968#endif
969		lp_table[i].last_error = 0;
970		init_waitqueue_head (&lp_table[i].waitq);
971		init_waitqueue_head (&lp_table[i].dataq);
972		mutex_init(&lp_table[i].port_mutex);
973		lp_table[i].timeout = 10 * HZ;
974	}
975
976	if (register_chrdev (LP_MAJOR, "lp", &lp_fops)) {
977		printk (KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
978		return -EIO;
979	}
980
981	lp_class = class_create(THIS_MODULE, "printer");
982	if (IS_ERR(lp_class)) {
983		err = PTR_ERR(lp_class);
984		goto out_reg;
985	}
986
987	if (parport_register_driver (&lp_driver)) {
988		printk (KERN_ERR "lp: unable to register with parport\n");
989		err = -EIO;
990		goto out_class;
991	}
992
993	if (!lp_count) {
994		printk (KERN_INFO "lp: driver loaded but no devices found\n");
995#ifndef CONFIG_PARPORT_1284
996		if (parport_nr[0] == LP_PARPORT_AUTO)
997			printk (KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
998#endif
999	}
1000
1001	return 0;
1002
1003out_class:
1004	class_destroy(lp_class);
1005out_reg:
1006	unregister_chrdev(LP_MAJOR, "lp");
1007	return err;
1008}
1009
1010static int __init lp_init_module (void)
1011{
1012	if (parport[0]) {
1013		/* The user gave some parameters.  Let's see what they were.  */
1014		if (!strncmp(parport[0], "auto", 4))
1015			parport_nr[0] = LP_PARPORT_AUTO;
1016		else {
1017			int n;
1018			for (n = 0; n < LP_NO && parport[n]; n++) {
1019				if (!strncmp(parport[n], "none", 4))
1020					parport_nr[n] = LP_PARPORT_NONE;
1021				else {
1022					char *ep;
1023					unsigned long r = simple_strtoul(parport[n], &ep, 0);
1024					if (ep != parport[n])
1025						parport_nr[n] = r;
1026					else {
1027						printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
1028						return -ENODEV;
1029					}
1030				}
1031			}
1032		}
1033	}
1034
1035	return lp_init();
1036}
1037
1038static void lp_cleanup_module (void)
1039{
1040	unsigned int offset;
1041
1042	parport_unregister_driver (&lp_driver);
1043
1044#ifdef CONFIG_LP_CONSOLE
1045	unregister_console (&lpcons);
1046#endif
1047
1048	unregister_chrdev(LP_MAJOR, "lp");
1049	for (offset = 0; offset < LP_NO; offset++) {
1050		if (lp_table[offset].dev == NULL)
1051			continue;
1052		parport_unregister_device(lp_table[offset].dev);
1053		device_destroy(lp_class, MKDEV(LP_MAJOR, offset));
1054	}
1055	class_destroy(lp_class);
1056}
1057
1058__setup("lp=", lp_setup);
1059module_init(lp_init_module);
1060module_exit(lp_cleanup_module);
1061
1062MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
1063MODULE_LICENSE("GPL");
1064