1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Generic parallel printer driver
4 *
5 * Copyright (C) 1992 by Jim Weigand and Linus Torvalds
6 * Copyright (C) 1992,1993 by Michael K. Johnson
7 * - Thanks much to Gunter Windau for pointing out to me where the error
8 * checking ought to be.
9 * Copyright (C) 1993 by Nigel Gamble (added interrupt code)
10 * Copyright (C) 1994 by Alan Cox (Modularised it)
11 * LPCAREFUL, LPABORT, LPGETSTATUS added by Chris Metcalf, metcalf@lcs.mit.edu
12 * Statistics and support for slow printers by Rob Janssen, rob@knoware.nl
13 * "lp=" command line parameters added by Grant Guenther, grant@torque.net
14 * lp_read (Status readback) support added by Carsten Gross,
15 * carsten@sol.wohnheim.uni-ulm.de
16 * Support for parport by Philip Blundell <philb@gnu.org>
17 * Parport sharing hacking by Andrea Arcangeli
18 * Fixed kernel_(to/from)_user memory copy to check for errors
19 * by Riccardo Facchetti <fizban@tin.it>
20 * 22-JAN-1998 Added support for devfs Richard Gooch <rgooch@atnf.csiro.au>
21 * Redesigned interrupt handling for handle printers with buggy handshake
22 * by Andrea Arcangeli, 11 May 1998
23 * Full efficient handling of printer with buggy irq handshake (now I have
24 * understood the meaning of the strange handshake). This is done sending new
25 * characters if the interrupt is just happened, even if the printer say to
26 * be still BUSY. This is needed at least with Epson Stylus Color. To enable
27 * the new TRUST_IRQ mode read the `LP OPTIMIZATION' section below...
28 * Fixed the irq on the rising edge of the strobe case.
29 * Obsoleted the CAREFUL flag since a printer that doesn' t work with
30 * CAREFUL will block a bit after in lp_check_status().
31 * Andrea Arcangeli, 15 Oct 1998
32 * Obsoleted and removed all the lowlevel stuff implemented in the last
33 * month to use the IEEE1284 functions (that handle the _new_ compatibilty
34 * mode fine).
35 */
36
37 /* This driver should, in theory, work with any parallel port that has an
38 * appropriate low-level driver; all I/O is done through the parport
39 * abstraction layer.
40 *
41 * If this driver is built into the kernel, you can configure it using the
42 * kernel command-line. For example:
43 *
44 * lp=parport1,none,parport2 (bind lp0 to parport1, disable lp1 and
45 * bind lp2 to parport2)
46 *
47 * lp=auto (assign lp devices to all ports that
48 * have printers attached, as determined
49 * by the IEEE-1284 autoprobe)
50 *
51 * lp=reset (reset the printer during
52 * initialisation)
53 *
54 * lp=off (disable the printer driver entirely)
55 *
56 * If the driver is loaded as a module, similar functionality is available
57 * using module parameters. The equivalent of the above commands would be:
58 *
59 * # insmod lp.o parport=1,none,2
60 *
61 * # insmod lp.o parport=auto
62 *
63 * # insmod lp.o reset=1
64 */
65
66 /* COMPATIBILITY WITH OLD KERNELS
67 *
68 * Under Linux 2.0 and previous versions, lp devices were bound to ports at
69 * particular I/O addresses, as follows:
70 *
71 * lp0 0x3bc
72 * lp1 0x378
73 * lp2 0x278
74 *
75 * The new driver, by default, binds lp devices to parport devices as it
76 * finds them. This means that if you only have one port, it will be bound
77 * to lp0 regardless of its I/O address. If you need the old behaviour, you
78 * can force it using the parameters described above.
79 */
80
81 /*
82 * The new interrupt handling code take care of the buggy handshake
83 * of some HP and Epson printer:
84 * ___
85 * ACK _______________ ___________
86 * |__|
87 * ____
88 * BUSY _________ _______
89 * |____________|
90 *
91 * I discovered this using the printer scanner that you can find at:
92 *
93 * ftp://e-mind.com/pub/linux/pscan/
94 *
95 * 11 May 98, Andrea Arcangeli
96 *
97 * My printer scanner run on an Epson Stylus Color show that such printer
98 * generates the irq on the _rising_ edge of the STROBE. Now lp handle
99 * this case fine too.
100 *
101 * 15 Oct 1998, Andrea Arcangeli
102 *
103 * The so called `buggy' handshake is really the well documented
104 * compatibility mode IEEE1284 handshake. They changed the well known
105 * Centronics handshake acking in the middle of busy expecting to not
106 * break drivers or legacy application, while they broken linux lp
107 * until I fixed it reverse engineering the protocol by hand some
108 * month ago...
109 *
110 * 14 Dec 1998, Andrea Arcangeli
111 *
112 * Copyright (C) 2000 by Tim Waugh (added LPSETTIMEOUT ioctl)
113 */
114
115 #include <linux/module.h>
116 #include <linux/init.h>
117
118 #include <linux/errno.h>
119 #include <linux/kernel.h>
120 #include <linux/major.h>
121 #include <linux/sched/signal.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 #include <linux/mutex.h>
131 #include <linux/compat.h>
132
133 #include <linux/parport.h>
134 #undef LP_STATS
135 #include <linux/lp.h>
136
137 #include <asm/irq.h>
138 #include <linux/uaccess.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 static int port_num[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;
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 */
lp_claim_parport_or_block(struct lp_struct * this_lp)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 */
lp_release_parport(struct lp_struct * this_lp)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
lp_preempt(void * handle)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 */
lp_negotiate(struct parport * port,int mode)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
lp_reset(int minor)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
lp_error(int minor)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)
229 lp_release_parport(&lp_table[minor]);
230 prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
231 schedule_timeout(LP_TIMEOUT_POLLED);
232 finish_wait(&lp_table[minor].waitq, &wait);
233 if (polling)
234 lp_claim_parport_or_block(&lp_table[minor]);
235 else
236 parport_yield_blocking(lp_table[minor].dev);
237 }
238
lp_check_status(int minor)239 static int lp_check_status(int minor)
240 {
241 int error = 0;
242 unsigned int last = lp_table[minor].last_error;
243 unsigned char status = r_str(minor);
244 if ((status & LP_PERRORP) && !(LP_F(minor) & LP_CAREFUL))
245 /* No error. */
246 last = 0;
247 else if ((status & LP_POUTPA)) {
248 if (last != LP_POUTPA) {
249 last = LP_POUTPA;
250 printk(KERN_INFO "lp%d out of paper\n", minor);
251 }
252 error = -ENOSPC;
253 } else if (!(status & LP_PSELECD)) {
254 if (last != LP_PSELECD) {
255 last = LP_PSELECD;
256 printk(KERN_INFO "lp%d off-line\n", minor);
257 }
258 error = -EIO;
259 } else if (!(status & LP_PERRORP)) {
260 if (last != LP_PERRORP) {
261 last = LP_PERRORP;
262 printk(KERN_INFO "lp%d on fire\n", minor);
263 }
264 error = -EIO;
265 } else {
266 last = 0; /* Come here if LP_CAREFUL is set and no
267 errors are reported. */
268 }
269
270 lp_table[minor].last_error = last;
271
272 if (last != 0)
273 lp_error(minor);
274
275 return error;
276 }
277
lp_wait_ready(int minor,int nonblock)278 static int lp_wait_ready(int minor, int nonblock)
279 {
280 int error = 0;
281
282 /* If we're not in compatibility mode, we're ready now! */
283 if (lp_table[minor].current_mode != IEEE1284_MODE_COMPAT) {
284 return 0;
285 }
286
287 do {
288 error = lp_check_status(minor);
289 if (error && (nonblock || (LP_F(minor) & LP_ABORT)))
290 break;
291 if (signal_pending(current)) {
292 error = -EINTR;
293 break;
294 }
295 } while (error);
296 return error;
297 }
298
lp_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)299 static ssize_t lp_write(struct file *file, const char __user *buf,
300 size_t count, loff_t *ppos)
301 {
302 unsigned int minor = iminor(file_inode(file));
303 struct parport *port = lp_table[minor].dev->port;
304 char *kbuf = lp_table[minor].lp_buffer;
305 ssize_t retv = 0;
306 ssize_t written;
307 size_t copy_size = count;
308 int nonblock = ((file->f_flags & O_NONBLOCK) ||
309 (LP_F(minor) & LP_ABORT));
310
311 #ifdef LP_STATS
312 if (time_after(jiffies, lp_table[minor].lastcall + LP_TIME(minor)))
313 lp_table[minor].runchars = 0;
314
315 lp_table[minor].lastcall = jiffies;
316 #endif
317
318 /* Need to copy the data from user-space. */
319 if (copy_size > LP_BUFFER_SIZE)
320 copy_size = LP_BUFFER_SIZE;
321
322 if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
323 return -EINTR;
324
325 if (copy_from_user(kbuf, buf, copy_size)) {
326 retv = -EFAULT;
327 goto out_unlock;
328 }
329
330 /* Claim Parport or sleep until it becomes available
331 */
332 lp_claim_parport_or_block(&lp_table[minor]);
333 /* Go to the proper mode. */
334 lp_table[minor].current_mode = lp_negotiate(port,
335 lp_table[minor].best_mode);
336
337 parport_set_timeout(lp_table[minor].dev,
338 (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
339 : lp_table[minor].timeout));
340
341 if ((retv = lp_wait_ready(minor, nonblock)) == 0)
342 do {
343 /* Write the data. */
344 written = parport_write(port, kbuf, copy_size);
345 if (written > 0) {
346 copy_size -= written;
347 count -= written;
348 buf += written;
349 retv += written;
350 }
351
352 if (signal_pending(current)) {
353 if (retv == 0)
354 retv = -EINTR;
355
356 break;
357 }
358
359 if (copy_size > 0) {
360 /* incomplete write -> check error ! */
361 int error;
362
363 parport_negotiate(lp_table[minor].dev->port,
364 IEEE1284_MODE_COMPAT);
365 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
366
367 error = lp_wait_ready(minor, nonblock);
368
369 if (error) {
370 if (retv == 0)
371 retv = error;
372 break;
373 } else if (nonblock) {
374 if (retv == 0)
375 retv = -EAGAIN;
376 break;
377 }
378
379 parport_yield_blocking(lp_table[minor].dev);
380 lp_table[minor].current_mode
381 = lp_negotiate(port,
382 lp_table[minor].best_mode);
383
384 } else if (need_resched())
385 schedule();
386
387 if (count) {
388 copy_size = count;
389 if (copy_size > LP_BUFFER_SIZE)
390 copy_size = LP_BUFFER_SIZE;
391
392 if (copy_from_user(kbuf, buf, copy_size)) {
393 if (retv == 0)
394 retv = -EFAULT;
395 break;
396 }
397 }
398 } while (count > 0);
399
400 if (test_and_clear_bit(LP_PREEMPT_REQUEST,
401 &lp_table[minor].bits)) {
402 printk(KERN_INFO "lp%d releasing parport\n", minor);
403 parport_negotiate(lp_table[minor].dev->port,
404 IEEE1284_MODE_COMPAT);
405 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
406 lp_release_parport(&lp_table[minor]);
407 }
408 out_unlock:
409 mutex_unlock(&lp_table[minor].port_mutex);
410
411 return retv;
412 }
413
414 #ifdef CONFIG_PARPORT_1284
415
416 /* Status readback conforming to ieee1284 */
lp_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)417 static ssize_t lp_read(struct file *file, char __user *buf,
418 size_t count, loff_t *ppos)
419 {
420 DEFINE_WAIT(wait);
421 unsigned int minor=iminor(file_inode(file));
422 struct parport *port = lp_table[minor].dev->port;
423 ssize_t retval = 0;
424 char *kbuf = lp_table[minor].lp_buffer;
425 int nonblock = ((file->f_flags & O_NONBLOCK) ||
426 (LP_F(minor) & LP_ABORT));
427
428 if (count > LP_BUFFER_SIZE)
429 count = LP_BUFFER_SIZE;
430
431 if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
432 return -EINTR;
433
434 lp_claim_parport_or_block(&lp_table[minor]);
435
436 parport_set_timeout(lp_table[minor].dev,
437 (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
438 : lp_table[minor].timeout));
439
440 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
441 if (parport_negotiate(lp_table[minor].dev->port,
442 IEEE1284_MODE_NIBBLE)) {
443 retval = -EIO;
444 goto out;
445 }
446
447 while (retval == 0) {
448 retval = parport_read(port, kbuf, count);
449
450 if (retval > 0)
451 break;
452
453 if (nonblock) {
454 retval = -EAGAIN;
455 break;
456 }
457
458 /* Wait for data. */
459
460 if (lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE) {
461 parport_negotiate(lp_table[minor].dev->port,
462 IEEE1284_MODE_COMPAT);
463 lp_error(minor);
464 if (parport_negotiate(lp_table[minor].dev->port,
465 IEEE1284_MODE_NIBBLE)) {
466 retval = -EIO;
467 goto out;
468 }
469 } else {
470 prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
471 schedule_timeout(LP_TIMEOUT_POLLED);
472 finish_wait(&lp_table[minor].waitq, &wait);
473 }
474
475 if (signal_pending(current)) {
476 retval = -ERESTARTSYS;
477 break;
478 }
479
480 cond_resched();
481 }
482 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
483 out:
484 lp_release_parport(&lp_table[minor]);
485
486 if (retval > 0 && copy_to_user(buf, kbuf, retval))
487 retval = -EFAULT;
488
489 mutex_unlock(&lp_table[minor].port_mutex);
490
491 return retval;
492 }
493
494 #endif /* IEEE 1284 support */
495
lp_open(struct inode * inode,struct file * file)496 static int lp_open(struct inode *inode, struct file *file)
497 {
498 unsigned int minor = iminor(inode);
499 int ret = 0;
500
501 mutex_lock(&lp_mutex);
502 if (minor >= LP_NO) {
503 ret = -ENXIO;
504 goto out;
505 }
506 if ((LP_F(minor) & LP_EXIST) == 0) {
507 ret = -ENXIO;
508 goto out;
509 }
510 if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor))) {
511 ret = -EBUSY;
512 goto out;
513 }
514 /* If ABORTOPEN is set and the printer is offline or out of paper,
515 we may still want to open it to perform ioctl()s. Therefore we
516 have commandeered O_NONBLOCK, even though it is being used in
517 a non-standard manner. This is strictly a Linux hack, and
518 should most likely only ever be used by the tunelp application. */
519 if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
520 int status;
521 lp_claim_parport_or_block(&lp_table[minor]);
522 status = r_str(minor);
523 lp_release_parport(&lp_table[minor]);
524 if (status & LP_POUTPA) {
525 printk(KERN_INFO "lp%d out of paper\n", minor);
526 LP_F(minor) &= ~LP_BUSY;
527 ret = -ENOSPC;
528 goto out;
529 } else if (!(status & LP_PSELECD)) {
530 printk(KERN_INFO "lp%d off-line\n", minor);
531 LP_F(minor) &= ~LP_BUSY;
532 ret = -EIO;
533 goto out;
534 } else if (!(status & LP_PERRORP)) {
535 printk(KERN_ERR "lp%d printer error\n", minor);
536 LP_F(minor) &= ~LP_BUSY;
537 ret = -EIO;
538 goto out;
539 }
540 }
541 lp_table[minor].lp_buffer = kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
542 if (!lp_table[minor].lp_buffer) {
543 LP_F(minor) &= ~LP_BUSY;
544 ret = -ENOMEM;
545 goto out;
546 }
547 /* Determine if the peripheral supports ECP mode */
548 lp_claim_parport_or_block(&lp_table[minor]);
549 if ( (lp_table[minor].dev->port->modes & PARPORT_MODE_ECP) &&
550 !parport_negotiate(lp_table[minor].dev->port,
551 IEEE1284_MODE_ECP)) {
552 printk(KERN_INFO "lp%d: ECP mode\n", minor);
553 lp_table[minor].best_mode = IEEE1284_MODE_ECP;
554 } else {
555 lp_table[minor].best_mode = IEEE1284_MODE_COMPAT;
556 }
557 /* Leave peripheral in compatibility mode */
558 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
559 lp_release_parport(&lp_table[minor]);
560 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
561 out:
562 mutex_unlock(&lp_mutex);
563 return ret;
564 }
565
lp_release(struct inode * inode,struct file * file)566 static int lp_release(struct inode *inode, struct file *file)
567 {
568 unsigned int minor = iminor(inode);
569
570 lp_claim_parport_or_block(&lp_table[minor]);
571 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
572 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
573 lp_release_parport(&lp_table[minor]);
574 kfree(lp_table[minor].lp_buffer);
575 lp_table[minor].lp_buffer = NULL;
576 LP_F(minor) &= ~LP_BUSY;
577 return 0;
578 }
579
lp_do_ioctl(unsigned int minor,unsigned int cmd,unsigned long arg,void __user * argp)580 static int lp_do_ioctl(unsigned int minor, unsigned int cmd,
581 unsigned long arg, void __user *argp)
582 {
583 int status;
584 int retval = 0;
585
586 #ifdef LP_DEBUG
587 printk(KERN_DEBUG "lp%d ioctl, cmd: 0x%x, arg: 0x%lx\n", minor, cmd, arg);
588 #endif
589 if (minor >= LP_NO)
590 return -ENODEV;
591 if ((LP_F(minor) & LP_EXIST) == 0)
592 return -ENODEV;
593 switch ( cmd ) {
594 case LPTIME:
595 if (arg > UINT_MAX / HZ)
596 return -EINVAL;
597 LP_TIME(minor) = arg * HZ/100;
598 break;
599 case LPCHAR:
600 LP_CHAR(minor) = arg;
601 break;
602 case LPABORT:
603 if (arg)
604 LP_F(minor) |= LP_ABORT;
605 else
606 LP_F(minor) &= ~LP_ABORT;
607 break;
608 case LPABORTOPEN:
609 if (arg)
610 LP_F(minor) |= LP_ABORTOPEN;
611 else
612 LP_F(minor) &= ~LP_ABORTOPEN;
613 break;
614 case LPCAREFUL:
615 if (arg)
616 LP_F(minor) |= LP_CAREFUL;
617 else
618 LP_F(minor) &= ~LP_CAREFUL;
619 break;
620 case LPWAIT:
621 LP_WAIT(minor) = arg;
622 break;
623 case LPSETIRQ:
624 return -EINVAL;
625 break;
626 case LPGETIRQ:
627 if (copy_to_user(argp, &LP_IRQ(minor),
628 sizeof(int)))
629 return -EFAULT;
630 break;
631 case LPGETSTATUS:
632 if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
633 return -EINTR;
634 lp_claim_parport_or_block(&lp_table[minor]);
635 status = r_str(minor);
636 lp_release_parport(&lp_table[minor]);
637 mutex_unlock(&lp_table[minor].port_mutex);
638
639 if (copy_to_user(argp, &status, sizeof(int)))
640 return -EFAULT;
641 break;
642 case LPRESET:
643 lp_reset(minor);
644 break;
645 #ifdef LP_STATS
646 case LPGETSTATS:
647 if (copy_to_user(argp, &LP_STAT(minor),
648 sizeof(struct lp_stats)))
649 return -EFAULT;
650 if (capable(CAP_SYS_ADMIN))
651 memset(&LP_STAT(minor), 0,
652 sizeof(struct lp_stats));
653 break;
654 #endif
655 case LPGETFLAGS:
656 status = LP_F(minor);
657 if (copy_to_user(argp, &status, sizeof(int)))
658 return -EFAULT;
659 break;
660
661 default:
662 retval = -EINVAL;
663 }
664 return retval;
665 }
666
lp_set_timeout(unsigned int minor,s64 tv_sec,long tv_usec)667 static int lp_set_timeout(unsigned int minor, s64 tv_sec, long tv_usec)
668 {
669 long to_jiffies;
670
671 /* Convert to jiffies, place in lp_table */
672 if (tv_sec < 0 || tv_usec < 0)
673 return -EINVAL;
674
675 /*
676 * we used to not check, so let's not make this fatal,
677 * but deal with user space passing a 32-bit tv_nsec in
678 * a 64-bit field, capping the timeout to 1 second
679 * worth of microseconds, and capping the total at
680 * MAX_JIFFY_OFFSET.
681 */
682 if (tv_usec > 999999)
683 tv_usec = 999999;
684
685 if (tv_sec >= MAX_SEC_IN_JIFFIES - 1) {
686 to_jiffies = MAX_JIFFY_OFFSET;
687 } else {
688 to_jiffies = DIV_ROUND_UP(tv_usec, 1000000/HZ);
689 to_jiffies += tv_sec * (long) HZ;
690 }
691
692 if (to_jiffies <= 0) {
693 return -EINVAL;
694 }
695 lp_table[minor].timeout = to_jiffies;
696 return 0;
697 }
698
lp_set_timeout32(unsigned int minor,void __user * arg)699 static int lp_set_timeout32(unsigned int minor, void __user *arg)
700 {
701 s32 karg[2];
702
703 if (copy_from_user(karg, arg, sizeof(karg)))
704 return -EFAULT;
705
706 return lp_set_timeout(minor, karg[0], karg[1]);
707 }
708
lp_set_timeout64(unsigned int minor,void __user * arg)709 static int lp_set_timeout64(unsigned int minor, void __user *arg)
710 {
711 s64 karg[2];
712
713 if (copy_from_user(karg, arg, sizeof(karg)))
714 return -EFAULT;
715
716 /* sparc64 suseconds_t is 32-bit only */
717 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
718 karg[1] >>= 32;
719
720 return lp_set_timeout(minor, karg[0], karg[1]);
721 }
722
lp_ioctl(struct file * file,unsigned int cmd,unsigned long arg)723 static long lp_ioctl(struct file *file, unsigned int cmd,
724 unsigned long arg)
725 {
726 unsigned int minor;
727 int ret;
728
729 minor = iminor(file_inode(file));
730 mutex_lock(&lp_mutex);
731 switch (cmd) {
732 case LPSETTIMEOUT_OLD:
733 if (BITS_PER_LONG == 32) {
734 ret = lp_set_timeout32(minor, (void __user *)arg);
735 break;
736 }
737 fallthrough; /* for 64-bit */
738 case LPSETTIMEOUT_NEW:
739 ret = lp_set_timeout64(minor, (void __user *)arg);
740 break;
741 default:
742 ret = lp_do_ioctl(minor, cmd, arg, (void __user *)arg);
743 break;
744 }
745 mutex_unlock(&lp_mutex);
746
747 return ret;
748 }
749
750 #ifdef CONFIG_COMPAT
lp_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)751 static long lp_compat_ioctl(struct file *file, unsigned int cmd,
752 unsigned long arg)
753 {
754 unsigned int minor;
755 int ret;
756
757 minor = iminor(file_inode(file));
758 mutex_lock(&lp_mutex);
759 switch (cmd) {
760 case LPSETTIMEOUT_OLD:
761 if (!COMPAT_USE_64BIT_TIME) {
762 ret = lp_set_timeout32(minor, (void __user *)arg);
763 break;
764 }
765 fallthrough; /* for x32 mode */
766 case LPSETTIMEOUT_NEW:
767 ret = lp_set_timeout64(minor, (void __user *)arg);
768 break;
769 #ifdef LP_STATS
770 case LPGETSTATS:
771 /* FIXME: add an implementation if you set LP_STATS */
772 ret = -EINVAL;
773 break;
774 #endif
775 default:
776 ret = lp_do_ioctl(minor, cmd, arg, compat_ptr(arg));
777 break;
778 }
779 mutex_unlock(&lp_mutex);
780
781 return ret;
782 }
783 #endif
784
785 static const struct file_operations lp_fops = {
786 .owner = THIS_MODULE,
787 .write = lp_write,
788 .unlocked_ioctl = lp_ioctl,
789 #ifdef CONFIG_COMPAT
790 .compat_ioctl = lp_compat_ioctl,
791 #endif
792 .open = lp_open,
793 .release = lp_release,
794 #ifdef CONFIG_PARPORT_1284
795 .read = lp_read,
796 #endif
797 .llseek = noop_llseek,
798 };
799
800 /* --- support for console on the line printer ----------------- */
801
802 #ifdef CONFIG_LP_CONSOLE
803
804 #define CONSOLE_LP 0
805
806 /* If the printer is out of paper, we can either lose the messages or
807 * stall until the printer is happy again. Define CONSOLE_LP_STRICT
808 * non-zero to get the latter behaviour. */
809 #define CONSOLE_LP_STRICT 1
810
811 /* The console must be locked when we get here. */
812
lp_console_write(struct console * co,const char * s,unsigned count)813 static void lp_console_write(struct console *co, const char *s,
814 unsigned count)
815 {
816 struct pardevice *dev = lp_table[CONSOLE_LP].dev;
817 struct parport *port = dev->port;
818 ssize_t written;
819
820 if (parport_claim(dev))
821 /* Nothing we can do. */
822 return;
823
824 parport_set_timeout(dev, 0);
825
826 /* Go to compatibility mode. */
827 parport_negotiate(port, IEEE1284_MODE_COMPAT);
828
829 do {
830 /* Write the data, converting LF->CRLF as we go. */
831 ssize_t canwrite = count;
832 char *lf = memchr(s, '\n', count);
833 if (lf)
834 canwrite = lf - s;
835
836 if (canwrite > 0) {
837 written = parport_write(port, s, canwrite);
838
839 if (written <= 0)
840 continue;
841
842 s += written;
843 count -= written;
844 canwrite -= written;
845 }
846
847 if (lf && canwrite <= 0) {
848 const char *crlf = "\r\n";
849 int i = 2;
850
851 /* Dodge the original '\n', and put '\r\n' instead. */
852 s++;
853 count--;
854 do {
855 written = parport_write(port, crlf, i);
856 if (written > 0) {
857 i -= written;
858 crlf += written;
859 }
860 } while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
861 }
862 } while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
863
864 parport_release(dev);
865 }
866
867 static struct console lpcons = {
868 .name = "lp",
869 .write = lp_console_write,
870 .flags = CON_PRINTBUFFER,
871 };
872
873 #endif /* console on line printer */
874
875 /* --- initialisation code ------------------------------------- */
876
877 static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
878 static char *parport[LP_NO];
879 static bool reset;
880
881 module_param_array(parport, charp, NULL, 0);
882 module_param(reset, bool, 0);
883
884 #ifndef MODULE
lp_setup(char * str)885 static int __init lp_setup(char *str)
886 {
887 static int parport_ptr;
888 int x;
889
890 if (get_option(&str, &x)) {
891 if (x == 0) {
892 /* disable driver on "lp=" or "lp=0" */
893 parport_nr[0] = LP_PARPORT_OFF;
894 } else {
895 printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
896 return 0;
897 }
898 } else if (!strncmp(str, "parport", 7)) {
899 int n = simple_strtoul(str+7, NULL, 10);
900 if (parport_ptr < LP_NO)
901 parport_nr[parport_ptr++] = n;
902 else
903 printk(KERN_INFO "lp: too many ports, %s ignored.\n",
904 str);
905 } else if (!strcmp(str, "auto")) {
906 parport_nr[0] = LP_PARPORT_AUTO;
907 } else if (!strcmp(str, "none")) {
908 if (parport_ptr < LP_NO)
909 parport_nr[parport_ptr++] = LP_PARPORT_NONE;
910 else
911 printk(KERN_INFO "lp: too many ports, %s ignored.\n",
912 str);
913 } else if (!strcmp(str, "reset")) {
914 reset = true;
915 }
916 return 1;
917 }
918 #endif
919
lp_register(int nr,struct parport * port)920 static int lp_register(int nr, struct parport *port)
921 {
922 struct pardev_cb ppdev_cb;
923
924 memset(&ppdev_cb, 0, sizeof(ppdev_cb));
925 ppdev_cb.preempt = lp_preempt;
926 ppdev_cb.private = &lp_table[nr];
927 lp_table[nr].dev = parport_register_dev_model(port, "lp",
928 &ppdev_cb, nr);
929 if (lp_table[nr].dev == NULL)
930 return 1;
931 lp_table[nr].flags |= LP_EXIST;
932
933 if (reset)
934 lp_reset(nr);
935
936 device_create(lp_class, port->dev, MKDEV(LP_MAJOR, nr), NULL,
937 "lp%d", nr);
938
939 printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name,
940 (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
941
942 #ifdef CONFIG_LP_CONSOLE
943 if (!nr) {
944 if (port->modes & PARPORT_MODE_SAFEININT) {
945 register_console(&lpcons);
946 console_registered = port;
947 printk(KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
948 } else
949 printk(KERN_ERR "lp%d: cannot run console on %s\n",
950 CONSOLE_LP, port->name);
951 }
952 #endif
953 port_num[nr] = port->number;
954
955 return 0;
956 }
957
lp_attach(struct parport * port)958 static void lp_attach(struct parport *port)
959 {
960 unsigned int i;
961
962 switch (parport_nr[0]) {
963 case LP_PARPORT_UNSPEC:
964 case LP_PARPORT_AUTO:
965 if (parport_nr[0] == LP_PARPORT_AUTO &&
966 port->probe_info[0].class != PARPORT_CLASS_PRINTER)
967 return;
968 if (lp_count == LP_NO) {
969 printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
970 return;
971 }
972 for (i = 0; i < LP_NO; i++)
973 if (port_num[i] == -1)
974 break;
975
976 if (!lp_register(i, port))
977 lp_count++;
978 break;
979
980 default:
981 for (i = 0; i < LP_NO; i++) {
982 if (port->number == parport_nr[i]) {
983 if (!lp_register(i, port))
984 lp_count++;
985 break;
986 }
987 }
988 break;
989 }
990 }
991
lp_detach(struct parport * port)992 static void lp_detach(struct parport *port)
993 {
994 int n;
995
996 /* Write this some day. */
997 #ifdef CONFIG_LP_CONSOLE
998 if (console_registered == port) {
999 unregister_console(&lpcons);
1000 console_registered = NULL;
1001 }
1002 #endif /* CONFIG_LP_CONSOLE */
1003
1004 for (n = 0; n < LP_NO; n++) {
1005 if (port_num[n] == port->number) {
1006 port_num[n] = -1;
1007 lp_count--;
1008 device_destroy(lp_class, MKDEV(LP_MAJOR, n));
1009 parport_unregister_device(lp_table[n].dev);
1010 }
1011 }
1012 }
1013
1014 static struct parport_driver lp_driver = {
1015 .name = "lp",
1016 .match_port = lp_attach,
1017 .detach = lp_detach,
1018 .devmodel = true,
1019 };
1020
lp_init(void)1021 static int __init lp_init(void)
1022 {
1023 int i, err = 0;
1024
1025 if (parport_nr[0] == LP_PARPORT_OFF)
1026 return 0;
1027
1028 for (i = 0; i < LP_NO; i++) {
1029 lp_table[i].dev = NULL;
1030 lp_table[i].flags = 0;
1031 lp_table[i].chars = LP_INIT_CHAR;
1032 lp_table[i].time = LP_INIT_TIME;
1033 lp_table[i].wait = LP_INIT_WAIT;
1034 lp_table[i].lp_buffer = NULL;
1035 #ifdef LP_STATS
1036 lp_table[i].lastcall = 0;
1037 lp_table[i].runchars = 0;
1038 memset(&lp_table[i].stats, 0, sizeof(struct lp_stats));
1039 #endif
1040 lp_table[i].last_error = 0;
1041 init_waitqueue_head(&lp_table[i].waitq);
1042 init_waitqueue_head(&lp_table[i].dataq);
1043 mutex_init(&lp_table[i].port_mutex);
1044 lp_table[i].timeout = 10 * HZ;
1045 port_num[i] = -1;
1046 }
1047
1048 if (register_chrdev(LP_MAJOR, "lp", &lp_fops)) {
1049 printk(KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
1050 return -EIO;
1051 }
1052
1053 lp_class = class_create(THIS_MODULE, "printer");
1054 if (IS_ERR(lp_class)) {
1055 err = PTR_ERR(lp_class);
1056 goto out_reg;
1057 }
1058
1059 if (parport_register_driver(&lp_driver)) {
1060 printk(KERN_ERR "lp: unable to register with parport\n");
1061 err = -EIO;
1062 goto out_class;
1063 }
1064
1065 if (!lp_count) {
1066 printk(KERN_INFO "lp: driver loaded but no devices found\n");
1067 #ifndef CONFIG_PARPORT_1284
1068 if (parport_nr[0] == LP_PARPORT_AUTO)
1069 printk(KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
1070 #endif
1071 }
1072
1073 return 0;
1074
1075 out_class:
1076 class_destroy(lp_class);
1077 out_reg:
1078 unregister_chrdev(LP_MAJOR, "lp");
1079 return err;
1080 }
1081
lp_init_module(void)1082 static int __init lp_init_module(void)
1083 {
1084 if (parport[0]) {
1085 /* The user gave some parameters. Let's see what they were. */
1086 if (!strncmp(parport[0], "auto", 4))
1087 parport_nr[0] = LP_PARPORT_AUTO;
1088 else {
1089 int n;
1090 for (n = 0; n < LP_NO && parport[n]; n++) {
1091 if (!strncmp(parport[n], "none", 4))
1092 parport_nr[n] = LP_PARPORT_NONE;
1093 else {
1094 char *ep;
1095 unsigned long r = simple_strtoul(parport[n], &ep, 0);
1096 if (ep != parport[n])
1097 parport_nr[n] = r;
1098 else {
1099 printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
1100 return -ENODEV;
1101 }
1102 }
1103 }
1104 }
1105 }
1106
1107 return lp_init();
1108 }
1109
lp_cleanup_module(void)1110 static void lp_cleanup_module(void)
1111 {
1112 parport_unregister_driver(&lp_driver);
1113
1114 #ifdef CONFIG_LP_CONSOLE
1115 unregister_console(&lpcons);
1116 #endif
1117
1118 unregister_chrdev(LP_MAJOR, "lp");
1119 class_destroy(lp_class);
1120 }
1121
1122 __setup("lp=", lp_setup);
1123 module_init(lp_init_module);
1124 module_exit(lp_cleanup_module);
1125
1126 MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
1127 MODULE_LICENSE("GPL");
1128
