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 const struct class lp_class = {
149 .name = "printer",
150 };
151
152 #ifdef CONFIG_LP_CONSOLE
153 static struct parport *console_registered;
154 #endif /* CONFIG_LP_CONSOLE */
155
156 #undef LP_DEBUG
157
158 /* Bits used to manage claiming the parport device */
159 #define LP_PREEMPT_REQUEST 1
160 #define LP_PARPORT_CLAIMED 2
161
162 /* --- low-level port access ----------------------------------- */
163
164 #define r_dtr(x) (parport_read_data(lp_table[(x)].dev->port))
165 #define r_str(x) (parport_read_status(lp_table[(x)].dev->port))
166 #define w_ctr(x,y) do { parport_write_control(lp_table[(x)].dev->port, (y)); } while (0)
167 #define w_dtr(x,y) do { parport_write_data(lp_table[(x)].dev->port, (y)); } while (0)
168
169 /* Claim the parport or block trying unless we've already claimed it */
lp_claim_parport_or_block(struct lp_struct * this_lp)170 static void lp_claim_parport_or_block(struct lp_struct *this_lp)
171 {
172 if (!test_and_set_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
173 parport_claim_or_block(this_lp->dev);
174 }
175 }
176
177 /* Claim the parport or block trying unless we've already claimed it */
lp_release_parport(struct lp_struct * this_lp)178 static void lp_release_parport(struct lp_struct *this_lp)
179 {
180 if (test_and_clear_bit(LP_PARPORT_CLAIMED, &this_lp->bits)) {
181 parport_release(this_lp->dev);
182 }
183 }
184
185
186
lp_preempt(void * handle)187 static int lp_preempt(void *handle)
188 {
189 struct lp_struct *this_lp = (struct lp_struct *)handle;
190 set_bit(LP_PREEMPT_REQUEST, &this_lp->bits);
191 return 1;
192 }
193
194
195 /*
196 * Try to negotiate to a new mode; if unsuccessful negotiate to
197 * compatibility mode. Return the mode we ended up in.
198 */
lp_negotiate(struct parport * port,int mode)199 static int lp_negotiate(struct parport *port, int mode)
200 {
201 if (parport_negotiate(port, mode) != 0) {
202 mode = IEEE1284_MODE_COMPAT;
203 parport_negotiate(port, mode);
204 }
205
206 return mode;
207 }
208
lp_reset(int minor)209 static int lp_reset(int minor)
210 {
211 int retval;
212 lp_claim_parport_or_block(&lp_table[minor]);
213 w_ctr(minor, LP_PSELECP);
214 udelay(LP_DELAY);
215 w_ctr(minor, LP_PSELECP | LP_PINITP);
216 retval = r_str(minor);
217 lp_release_parport(&lp_table[minor]);
218 return retval;
219 }
220
lp_error(int minor)221 static void lp_error(int minor)
222 {
223 DEFINE_WAIT(wait);
224 int polling;
225
226 if (LP_F(minor) & LP_ABORT)
227 return;
228
229 polling = lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE;
230 if (polling)
231 lp_release_parport(&lp_table[minor]);
232 prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
233 schedule_timeout(LP_TIMEOUT_POLLED);
234 finish_wait(&lp_table[minor].waitq, &wait);
235 if (polling)
236 lp_claim_parport_or_block(&lp_table[minor]);
237 else
238 parport_yield_blocking(lp_table[minor].dev);
239 }
240
lp_check_status(int minor)241 static int lp_check_status(int minor)
242 {
243 int error = 0;
244 unsigned int last = lp_table[minor].last_error;
245 unsigned char status = r_str(minor);
246 if ((status & LP_PERRORP) && !(LP_F(minor) & LP_CAREFUL))
247 /* No error. */
248 last = 0;
249 else if ((status & LP_POUTPA)) {
250 if (last != LP_POUTPA) {
251 last = LP_POUTPA;
252 printk(KERN_INFO "lp%d out of paper\n", minor);
253 }
254 error = -ENOSPC;
255 } else if (!(status & LP_PSELECD)) {
256 if (last != LP_PSELECD) {
257 last = LP_PSELECD;
258 printk(KERN_INFO "lp%d off-line\n", minor);
259 }
260 error = -EIO;
261 } else if (!(status & LP_PERRORP)) {
262 if (last != LP_PERRORP) {
263 last = LP_PERRORP;
264 printk(KERN_INFO "lp%d on fire\n", minor);
265 }
266 error = -EIO;
267 } else {
268 last = 0; /* Come here if LP_CAREFUL is set and no
269 errors are reported. */
270 }
271
272 lp_table[minor].last_error = last;
273
274 if (last != 0)
275 lp_error(minor);
276
277 return error;
278 }
279
lp_wait_ready(int minor,int nonblock)280 static int lp_wait_ready(int minor, int nonblock)
281 {
282 int error = 0;
283
284 /* If we're not in compatibility mode, we're ready now! */
285 if (lp_table[minor].current_mode != IEEE1284_MODE_COMPAT) {
286 return 0;
287 }
288
289 do {
290 error = lp_check_status(minor);
291 if (error && (nonblock || (LP_F(minor) & LP_ABORT)))
292 break;
293 if (signal_pending(current)) {
294 error = -EINTR;
295 break;
296 }
297 } while (error);
298 return error;
299 }
300
lp_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)301 static ssize_t lp_write(struct file *file, const char __user *buf,
302 size_t count, loff_t *ppos)
303 {
304 unsigned int minor = iminor(file_inode(file));
305 struct parport *port = lp_table[minor].dev->port;
306 char *kbuf = lp_table[minor].lp_buffer;
307 ssize_t retv = 0;
308 ssize_t written;
309 size_t copy_size = count;
310 int nonblock = ((file->f_flags & O_NONBLOCK) ||
311 (LP_F(minor) & LP_ABORT));
312
313 #ifdef LP_STATS
314 if (time_after(jiffies, lp_table[minor].lastcall + LP_TIME(minor)))
315 lp_table[minor].runchars = 0;
316
317 lp_table[minor].lastcall = jiffies;
318 #endif
319
320 /* Need to copy the data from user-space. */
321 if (copy_size > LP_BUFFER_SIZE)
322 copy_size = LP_BUFFER_SIZE;
323
324 if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
325 return -EINTR;
326
327 if (copy_from_user(kbuf, buf, copy_size)) {
328 retv = -EFAULT;
329 goto out_unlock;
330 }
331
332 /* Claim Parport or sleep until it becomes available
333 */
334 lp_claim_parport_or_block(&lp_table[minor]);
335 /* Go to the proper mode. */
336 lp_table[minor].current_mode = lp_negotiate(port,
337 lp_table[minor].best_mode);
338
339 parport_set_timeout(lp_table[minor].dev,
340 (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
341 : lp_table[minor].timeout));
342
343 if ((retv = lp_wait_ready(minor, nonblock)) == 0)
344 do {
345 /* Write the data. */
346 written = parport_write(port, kbuf, copy_size);
347 if (written > 0) {
348 copy_size -= written;
349 count -= written;
350 buf += written;
351 retv += written;
352 }
353
354 if (signal_pending(current)) {
355 if (retv == 0)
356 retv = -EINTR;
357
358 break;
359 }
360
361 if (copy_size > 0) {
362 /* incomplete write -> check error ! */
363 int error;
364
365 parport_negotiate(lp_table[minor].dev->port,
366 IEEE1284_MODE_COMPAT);
367 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
368
369 error = lp_wait_ready(minor, nonblock);
370
371 if (error) {
372 if (retv == 0)
373 retv = error;
374 break;
375 } else if (nonblock) {
376 if (retv == 0)
377 retv = -EAGAIN;
378 break;
379 }
380
381 parport_yield_blocking(lp_table[minor].dev);
382 lp_table[minor].current_mode
383 = lp_negotiate(port,
384 lp_table[minor].best_mode);
385
386 } else if (need_resched())
387 schedule();
388
389 if (count) {
390 copy_size = count;
391 if (copy_size > LP_BUFFER_SIZE)
392 copy_size = LP_BUFFER_SIZE;
393
394 if (copy_from_user(kbuf, buf, copy_size)) {
395 if (retv == 0)
396 retv = -EFAULT;
397 break;
398 }
399 }
400 } while (count > 0);
401
402 if (test_and_clear_bit(LP_PREEMPT_REQUEST,
403 &lp_table[minor].bits)) {
404 printk(KERN_INFO "lp%d releasing parport\n", minor);
405 parport_negotiate(lp_table[minor].dev->port,
406 IEEE1284_MODE_COMPAT);
407 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
408 lp_release_parport(&lp_table[minor]);
409 }
410 out_unlock:
411 mutex_unlock(&lp_table[minor].port_mutex);
412
413 return retv;
414 }
415
416 #ifdef CONFIG_PARPORT_1284
417
418 /* Status readback conforming to ieee1284 */
lp_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)419 static ssize_t lp_read(struct file *file, char __user *buf,
420 size_t count, loff_t *ppos)
421 {
422 DEFINE_WAIT(wait);
423 unsigned int minor=iminor(file_inode(file));
424 struct parport *port = lp_table[minor].dev->port;
425 ssize_t retval = 0;
426 char *kbuf = lp_table[minor].lp_buffer;
427 int nonblock = ((file->f_flags & O_NONBLOCK) ||
428 (LP_F(minor) & LP_ABORT));
429
430 if (count > LP_BUFFER_SIZE)
431 count = LP_BUFFER_SIZE;
432
433 if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
434 return -EINTR;
435
436 lp_claim_parport_or_block(&lp_table[minor]);
437
438 parport_set_timeout(lp_table[minor].dev,
439 (nonblock ? PARPORT_INACTIVITY_O_NONBLOCK
440 : lp_table[minor].timeout));
441
442 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
443 if (parport_negotiate(lp_table[minor].dev->port,
444 IEEE1284_MODE_NIBBLE)) {
445 retval = -EIO;
446 goto out;
447 }
448
449 while (retval == 0) {
450 retval = parport_read(port, kbuf, count);
451
452 if (retval > 0)
453 break;
454
455 if (nonblock) {
456 retval = -EAGAIN;
457 break;
458 }
459
460 /* Wait for data. */
461
462 if (lp_table[minor].dev->port->irq == PARPORT_IRQ_NONE) {
463 parport_negotiate(lp_table[minor].dev->port,
464 IEEE1284_MODE_COMPAT);
465 lp_error(minor);
466 if (parport_negotiate(lp_table[minor].dev->port,
467 IEEE1284_MODE_NIBBLE)) {
468 retval = -EIO;
469 goto out;
470 }
471 } else {
472 prepare_to_wait(&lp_table[minor].waitq, &wait, TASK_INTERRUPTIBLE);
473 schedule_timeout(LP_TIMEOUT_POLLED);
474 finish_wait(&lp_table[minor].waitq, &wait);
475 }
476
477 if (signal_pending(current)) {
478 retval = -ERESTARTSYS;
479 break;
480 }
481
482 cond_resched();
483 }
484 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
485 out:
486 lp_release_parport(&lp_table[minor]);
487
488 if (retval > 0 && copy_to_user(buf, kbuf, retval))
489 retval = -EFAULT;
490
491 mutex_unlock(&lp_table[minor].port_mutex);
492
493 return retval;
494 }
495
496 #endif /* IEEE 1284 support */
497
lp_open(struct inode * inode,struct file * file)498 static int lp_open(struct inode *inode, struct file *file)
499 {
500 unsigned int minor = iminor(inode);
501 int ret = 0;
502
503 mutex_lock(&lp_mutex);
504 if (minor >= LP_NO) {
505 ret = -ENXIO;
506 goto out;
507 }
508 if ((LP_F(minor) & LP_EXIST) == 0) {
509 ret = -ENXIO;
510 goto out;
511 }
512 if (test_and_set_bit(LP_BUSY_BIT_POS, &LP_F(minor))) {
513 ret = -EBUSY;
514 goto out;
515 }
516 /* If ABORTOPEN is set and the printer is offline or out of paper,
517 we may still want to open it to perform ioctl()s. Therefore we
518 have commandeered O_NONBLOCK, even though it is being used in
519 a non-standard manner. This is strictly a Linux hack, and
520 should most likely only ever be used by the tunelp application. */
521 if ((LP_F(minor) & LP_ABORTOPEN) && !(file->f_flags & O_NONBLOCK)) {
522 int status;
523 lp_claim_parport_or_block(&lp_table[minor]);
524 status = r_str(minor);
525 lp_release_parport(&lp_table[minor]);
526 if (status & LP_POUTPA) {
527 printk(KERN_INFO "lp%d out of paper\n", minor);
528 LP_F(minor) &= ~LP_BUSY;
529 ret = -ENOSPC;
530 goto out;
531 } else if (!(status & LP_PSELECD)) {
532 printk(KERN_INFO "lp%d off-line\n", minor);
533 LP_F(minor) &= ~LP_BUSY;
534 ret = -EIO;
535 goto out;
536 } else if (!(status & LP_PERRORP)) {
537 printk(KERN_ERR "lp%d printer error\n", minor);
538 LP_F(minor) &= ~LP_BUSY;
539 ret = -EIO;
540 goto out;
541 }
542 }
543 lp_table[minor].lp_buffer = kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
544 if (!lp_table[minor].lp_buffer) {
545 LP_F(minor) &= ~LP_BUSY;
546 ret = -ENOMEM;
547 goto out;
548 }
549 /* Determine if the peripheral supports ECP mode */
550 lp_claim_parport_or_block(&lp_table[minor]);
551 if ((lp_table[minor].dev->port->modes & PARPORT_MODE_ECP) &&
552 !parport_negotiate(lp_table[minor].dev->port,
553 IEEE1284_MODE_ECP)) {
554 printk(KERN_INFO "lp%d: ECP mode\n", minor);
555 lp_table[minor].best_mode = IEEE1284_MODE_ECP;
556 } else {
557 lp_table[minor].best_mode = IEEE1284_MODE_COMPAT;
558 }
559 /* Leave peripheral in compatibility mode */
560 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
561 lp_release_parport(&lp_table[minor]);
562 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
563 out:
564 mutex_unlock(&lp_mutex);
565 return ret;
566 }
567
lp_release(struct inode * inode,struct file * file)568 static int lp_release(struct inode *inode, struct file *file)
569 {
570 unsigned int minor = iminor(inode);
571
572 lp_claim_parport_or_block(&lp_table[minor]);
573 parport_negotiate(lp_table[minor].dev->port, IEEE1284_MODE_COMPAT);
574 lp_table[minor].current_mode = IEEE1284_MODE_COMPAT;
575 lp_release_parport(&lp_table[minor]);
576 kfree(lp_table[minor].lp_buffer);
577 lp_table[minor].lp_buffer = NULL;
578 LP_F(minor) &= ~LP_BUSY;
579 return 0;
580 }
581
lp_do_ioctl(unsigned int minor,unsigned int cmd,unsigned long arg,void __user * argp)582 static int lp_do_ioctl(unsigned int minor, unsigned int cmd,
583 unsigned long arg, void __user *argp)
584 {
585 int status;
586 int retval = 0;
587
588 #ifdef LP_DEBUG
589 printk(KERN_DEBUG "lp%d ioctl, cmd: 0x%x, arg: 0x%lx\n", minor, cmd, arg);
590 #endif
591 if (minor >= LP_NO)
592 return -ENODEV;
593 if ((LP_F(minor) & LP_EXIST) == 0)
594 return -ENODEV;
595 switch (cmd) {
596 case LPTIME:
597 if (arg > UINT_MAX / HZ)
598 return -EINVAL;
599 LP_TIME(minor) = arg * HZ/100;
600 break;
601 case LPCHAR:
602 LP_CHAR(minor) = arg;
603 break;
604 case LPABORT:
605 if (arg)
606 LP_F(minor) |= LP_ABORT;
607 else
608 LP_F(minor) &= ~LP_ABORT;
609 break;
610 case LPABORTOPEN:
611 if (arg)
612 LP_F(minor) |= LP_ABORTOPEN;
613 else
614 LP_F(minor) &= ~LP_ABORTOPEN;
615 break;
616 case LPCAREFUL:
617 if (arg)
618 LP_F(minor) |= LP_CAREFUL;
619 else
620 LP_F(minor) &= ~LP_CAREFUL;
621 break;
622 case LPWAIT:
623 LP_WAIT(minor) = arg;
624 break;
625 case LPSETIRQ:
626 return -EINVAL;
627 case LPGETIRQ:
628 if (copy_to_user(argp, &LP_IRQ(minor),
629 sizeof(int)))
630 return -EFAULT;
631 break;
632 case LPGETSTATUS:
633 if (mutex_lock_interruptible(&lp_table[minor].port_mutex))
634 return -EINTR;
635 lp_claim_parport_or_block(&lp_table[minor]);
636 status = r_str(minor);
637 lp_release_parport(&lp_table[minor]);
638 mutex_unlock(&lp_table[minor].port_mutex);
639
640 if (copy_to_user(argp, &status, sizeof(int)))
641 return -EFAULT;
642 break;
643 case LPRESET:
644 lp_reset(minor);
645 break;
646 #ifdef LP_STATS
647 case LPGETSTATS:
648 if (copy_to_user(argp, &LP_STAT(minor),
649 sizeof(struct lp_stats)))
650 return -EFAULT;
651 if (capable(CAP_SYS_ADMIN))
652 memset(&LP_STAT(minor), 0,
653 sizeof(struct lp_stats));
654 break;
655 #endif
656 case LPGETFLAGS:
657 status = LP_F(minor);
658 if (copy_to_user(argp, &status, sizeof(int)))
659 return -EFAULT;
660 break;
661
662 default:
663 retval = -EINVAL;
664 }
665 return retval;
666 }
667
lp_set_timeout(unsigned int minor,s64 tv_sec,long tv_usec)668 static int lp_set_timeout(unsigned int minor, s64 tv_sec, long tv_usec)
669 {
670 long to_jiffies;
671
672 /* Convert to jiffies, place in lp_table */
673 if (tv_sec < 0 || tv_usec < 0)
674 return -EINVAL;
675
676 /*
677 * we used to not check, so let's not make this fatal,
678 * but deal with user space passing a 32-bit tv_nsec in
679 * a 64-bit field, capping the timeout to 1 second
680 * worth of microseconds, and capping the total at
681 * MAX_JIFFY_OFFSET.
682 */
683 if (tv_usec > 999999)
684 tv_usec = 999999;
685
686 if (tv_sec >= MAX_SEC_IN_JIFFIES - 1) {
687 to_jiffies = MAX_JIFFY_OFFSET;
688 } else {
689 to_jiffies = DIV_ROUND_UP(tv_usec, 1000000/HZ);
690 to_jiffies += tv_sec * (long) HZ;
691 }
692
693 if (to_jiffies <= 0) {
694 return -EINVAL;
695 }
696 lp_table[minor].timeout = to_jiffies;
697 return 0;
698 }
699
lp_set_timeout32(unsigned int minor,void __user * arg)700 static int lp_set_timeout32(unsigned int minor, void __user *arg)
701 {
702 s32 karg[2];
703
704 if (copy_from_user(karg, arg, sizeof(karg)))
705 return -EFAULT;
706
707 return lp_set_timeout(minor, karg[0], karg[1]);
708 }
709
lp_set_timeout64(unsigned int minor,void __user * arg)710 static int lp_set_timeout64(unsigned int minor, void __user *arg)
711 {
712 s64 karg[2];
713
714 if (copy_from_user(karg, arg, sizeof(karg)))
715 return -EFAULT;
716
717 /* sparc64 suseconds_t is 32-bit only */
718 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall())
719 karg[1] >>= 32;
720
721 return lp_set_timeout(minor, karg[0], karg[1]);
722 }
723
lp_ioctl(struct file * file,unsigned int cmd,unsigned long arg)724 static long lp_ioctl(struct file *file, unsigned int cmd,
725 unsigned long arg)
726 {
727 unsigned int minor;
728 int ret;
729
730 minor = iminor(file_inode(file));
731 mutex_lock(&lp_mutex);
732 switch (cmd) {
733 case LPSETTIMEOUT_OLD:
734 if (BITS_PER_LONG == 32) {
735 ret = lp_set_timeout32(minor, (void __user *)arg);
736 break;
737 }
738 fallthrough; /* for 64-bit */
739 case LPSETTIMEOUT_NEW:
740 ret = lp_set_timeout64(minor, (void __user *)arg);
741 break;
742 default:
743 ret = lp_do_ioctl(minor, cmd, arg, (void __user *)arg);
744 break;
745 }
746 mutex_unlock(&lp_mutex);
747
748 return ret;
749 }
750
751 #ifdef CONFIG_COMPAT
lp_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)752 static long lp_compat_ioctl(struct file *file, unsigned int cmd,
753 unsigned long arg)
754 {
755 unsigned int minor;
756 int ret;
757
758 minor = iminor(file_inode(file));
759 mutex_lock(&lp_mutex);
760 switch (cmd) {
761 case LPSETTIMEOUT_OLD:
762 if (!COMPAT_USE_64BIT_TIME) {
763 ret = lp_set_timeout32(minor, (void __user *)arg);
764 break;
765 }
766 fallthrough; /* for x32 mode */
767 case LPSETTIMEOUT_NEW:
768 ret = lp_set_timeout64(minor, (void __user *)arg);
769 break;
770 #ifdef LP_STATS
771 case LPGETSTATS:
772 /* FIXME: add an implementation if you set LP_STATS */
773 ret = -EINVAL;
774 break;
775 #endif
776 default:
777 ret = lp_do_ioctl(minor, cmd, arg, compat_ptr(arg));
778 break;
779 }
780 mutex_unlock(&lp_mutex);
781
782 return ret;
783 }
784 #endif
785
786 static const struct file_operations lp_fops = {
787 .owner = THIS_MODULE,
788 .write = lp_write,
789 .unlocked_ioctl = lp_ioctl,
790 #ifdef CONFIG_COMPAT
791 .compat_ioctl = lp_compat_ioctl,
792 #endif
793 .open = lp_open,
794 .release = lp_release,
795 #ifdef CONFIG_PARPORT_1284
796 .read = lp_read,
797 #endif
798 .llseek = noop_llseek,
799 };
800
801 /* --- support for console on the line printer ----------------- */
802
803 #ifdef CONFIG_LP_CONSOLE
804
805 #define CONSOLE_LP 0
806
807 /* If the printer is out of paper, we can either lose the messages or
808 * stall until the printer is happy again. Define CONSOLE_LP_STRICT
809 * non-zero to get the latter behaviour. */
810 #define CONSOLE_LP_STRICT 1
811
812 /* The console must be locked when we get here. */
813
lp_console_write(struct console * co,const char * s,unsigned count)814 static void lp_console_write(struct console *co, const char *s,
815 unsigned count)
816 {
817 struct pardevice *dev = lp_table[CONSOLE_LP].dev;
818 struct parport *port = dev->port;
819 ssize_t written;
820
821 if (parport_claim(dev))
822 /* Nothing we can do. */
823 return;
824
825 parport_set_timeout(dev, 0);
826
827 /* Go to compatibility mode. */
828 parport_negotiate(port, IEEE1284_MODE_COMPAT);
829
830 do {
831 /* Write the data, converting LF->CRLF as we go. */
832 ssize_t canwrite = count;
833 char *lf = memchr(s, '\n', count);
834 if (lf)
835 canwrite = lf - s;
836
837 if (canwrite > 0) {
838 written = parport_write(port, s, canwrite);
839
840 if (written <= 0)
841 continue;
842
843 s += written;
844 count -= written;
845 canwrite -= written;
846 }
847
848 if (lf && canwrite <= 0) {
849 const char *crlf = "\r\n";
850 int i = 2;
851
852 /* Dodge the original '\n', and put '\r\n' instead. */
853 s++;
854 count--;
855 do {
856 written = parport_write(port, crlf, i);
857 if (written > 0) {
858 i -= written;
859 crlf += written;
860 }
861 } while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
862 }
863 } while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
864
865 parport_release(dev);
866 }
867
868 static struct console lpcons = {
869 .name = "lp",
870 .write = lp_console_write,
871 .flags = CON_PRINTBUFFER,
872 };
873
874 #endif /* console on line printer */
875
876 /* --- initialisation code ------------------------------------- */
877
878 static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
879 static char *parport[LP_NO];
880 static bool reset;
881
882 module_param_array(parport, charp, NULL, 0);
883 module_param(reset, bool, 0);
884
885 #ifndef MODULE
lp_setup(char * str)886 static int __init lp_setup(char *str)
887 {
888 static int parport_ptr;
889 int x;
890
891 if (get_option(&str, &x)) {
892 if (x == 0) {
893 /* disable driver on "lp=" or "lp=0" */
894 parport_nr[0] = LP_PARPORT_OFF;
895 } else {
896 printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
897 return 0;
898 }
899 } else if (!strncmp(str, "parport", 7)) {
900 int n = simple_strtoul(str+7, NULL, 10);
901 if (parport_ptr < LP_NO)
902 parport_nr[parport_ptr++] = n;
903 else
904 printk(KERN_INFO "lp: too many ports, %s ignored.\n",
905 str);
906 } else if (!strcmp(str, "auto")) {
907 parport_nr[0] = LP_PARPORT_AUTO;
908 } else if (!strcmp(str, "none")) {
909 if (parport_ptr < LP_NO)
910 parport_nr[parport_ptr++] = LP_PARPORT_NONE;
911 else
912 printk(KERN_INFO "lp: too many ports, %s ignored.\n",
913 str);
914 } else if (!strcmp(str, "reset")) {
915 reset = true;
916 }
917 return 1;
918 }
919 #endif
920
lp_register(int nr,struct parport * port)921 static int lp_register(int nr, struct parport *port)
922 {
923 struct pardev_cb ppdev_cb;
924
925 memset(&ppdev_cb, 0, sizeof(ppdev_cb));
926 ppdev_cb.preempt = lp_preempt;
927 ppdev_cb.private = &lp_table[nr];
928 lp_table[nr].dev = parport_register_dev_model(port, "lp",
929 &ppdev_cb, nr);
930 if (lp_table[nr].dev == NULL)
931 return 1;
932 lp_table[nr].flags |= LP_EXIST;
933
934 if (reset)
935 lp_reset(nr);
936
937 device_create(&lp_class, port->dev, MKDEV(LP_MAJOR, nr), NULL,
938 "lp%d", nr);
939
940 printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name,
941 (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
942
943 #ifdef CONFIG_LP_CONSOLE
944 if (!nr) {
945 if (port->modes & PARPORT_MODE_SAFEININT) {
946 register_console(&lpcons);
947 console_registered = port;
948 printk(KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
949 } else
950 printk(KERN_ERR "lp%d: cannot run console on %s\n",
951 CONSOLE_LP, port->name);
952 }
953 #endif
954 port_num[nr] = port->number;
955
956 return 0;
957 }
958
lp_attach(struct parport * port)959 static void lp_attach(struct parport *port)
960 {
961 unsigned int i;
962
963 switch (parport_nr[0]) {
964 case LP_PARPORT_UNSPEC:
965 case LP_PARPORT_AUTO:
966 if (parport_nr[0] == LP_PARPORT_AUTO &&
967 port->probe_info[0].class != PARPORT_CLASS_PRINTER)
968 return;
969 if (lp_count == LP_NO) {
970 printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
971 return;
972 }
973 for (i = 0; i < LP_NO; i++)
974 if (port_num[i] == -1)
975 break;
976
977 if (!lp_register(i, port))
978 lp_count++;
979 break;
980
981 default:
982 for (i = 0; i < LP_NO; i++) {
983 if (port->number == parport_nr[i]) {
984 if (!lp_register(i, port))
985 lp_count++;
986 break;
987 }
988 }
989 break;
990 }
991 }
992
lp_detach(struct parport * port)993 static void lp_detach(struct parport *port)
994 {
995 int n;
996
997 /* Write this some day. */
998 #ifdef CONFIG_LP_CONSOLE
999 if (console_registered == port) {
1000 unregister_console(&lpcons);
1001 console_registered = NULL;
1002 }
1003 #endif /* CONFIG_LP_CONSOLE */
1004
1005 for (n = 0; n < LP_NO; n++) {
1006 if (port_num[n] == port->number) {
1007 port_num[n] = -1;
1008 lp_count--;
1009 device_destroy(&lp_class, MKDEV(LP_MAJOR, n));
1010 parport_unregister_device(lp_table[n].dev);
1011 }
1012 }
1013 }
1014
1015 static struct parport_driver lp_driver = {
1016 .name = "lp",
1017 .match_port = lp_attach,
1018 .detach = lp_detach,
1019 .devmodel = true,
1020 };
1021
lp_init(void)1022 static int __init lp_init(void)
1023 {
1024 int i, err;
1025
1026 if (parport_nr[0] == LP_PARPORT_OFF)
1027 return 0;
1028
1029 for (i = 0; i < LP_NO; i++) {
1030 lp_table[i].dev = NULL;
1031 lp_table[i].flags = 0;
1032 lp_table[i].chars = LP_INIT_CHAR;
1033 lp_table[i].time = LP_INIT_TIME;
1034 lp_table[i].wait = LP_INIT_WAIT;
1035 lp_table[i].lp_buffer = NULL;
1036 #ifdef LP_STATS
1037 lp_table[i].lastcall = 0;
1038 lp_table[i].runchars = 0;
1039 memset(&lp_table[i].stats, 0, sizeof(struct lp_stats));
1040 #endif
1041 lp_table[i].last_error = 0;
1042 init_waitqueue_head(&lp_table[i].waitq);
1043 init_waitqueue_head(&lp_table[i].dataq);
1044 mutex_init(&lp_table[i].port_mutex);
1045 lp_table[i].timeout = 10 * HZ;
1046 port_num[i] = -1;
1047 }
1048
1049 if (register_chrdev(LP_MAJOR, "lp", &lp_fops)) {
1050 printk(KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
1051 return -EIO;
1052 }
1053
1054 err = class_register(&lp_class);
1055 if (err)
1056 goto out_reg;
1057
1058 if (parport_register_driver(&lp_driver)) {
1059 printk(KERN_ERR "lp: unable to register with parport\n");
1060 err = -EIO;
1061 goto out_class;
1062 }
1063
1064 if (!lp_count) {
1065 printk(KERN_INFO "lp: driver loaded but no devices found\n");
1066 #ifndef CONFIG_PARPORT_1284
1067 if (parport_nr[0] == LP_PARPORT_AUTO)
1068 printk(KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
1069 #endif
1070 }
1071
1072 return 0;
1073
1074 out_class:
1075 class_unregister(&lp_class);
1076 out_reg:
1077 unregister_chrdev(LP_MAJOR, "lp");
1078 return err;
1079 }
1080
lp_init_module(void)1081 static int __init lp_init_module(void)
1082 {
1083 if (parport[0]) {
1084 /* The user gave some parameters. Let's see what they were. */
1085 if (!strncmp(parport[0], "auto", 4))
1086 parport_nr[0] = LP_PARPORT_AUTO;
1087 else {
1088 int n;
1089 for (n = 0; n < LP_NO && parport[n]; n++) {
1090 if (!strncmp(parport[n], "none", 4))
1091 parport_nr[n] = LP_PARPORT_NONE;
1092 else {
1093 char *ep;
1094 unsigned long r = simple_strtoul(parport[n], &ep, 0);
1095 if (ep != parport[n])
1096 parport_nr[n] = r;
1097 else {
1098 printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
1099 return -ENODEV;
1100 }
1101 }
1102 }
1103 }
1104 }
1105
1106 return lp_init();
1107 }
1108
lp_cleanup_module(void)1109 static void lp_cleanup_module(void)
1110 {
1111 parport_unregister_driver(&lp_driver);
1112
1113 #ifdef CONFIG_LP_CONSOLE
1114 unregister_console(&lpcons);
1115 #endif
1116
1117 unregister_chrdev(LP_MAJOR, "lp");
1118 class_unregister(&lp_class);
1119 }
1120
1121 __setup("lp=", lp_setup);
1122 module_init(lp_init_module);
1123 module_exit(lp_cleanup_module);
1124
1125 MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
1126 MODULE_LICENSE("GPL");
1127