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
 143static DEFINE_MUTEX(lp_mutex);
 144static struct lp_struct lp_table[LP_NO];
 145static int port_num[LP_NO];
 146
 147static unsigned int lp_count = 0;
 148static struct class *lp_class;
 149
 150#ifdef CONFIG_LP_CONSOLE
 151static 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 */
 168static 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 */
 176static 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
 185static 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 */
 197static 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
 207static 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
 219static 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
 239static 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
 278static 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
 299static 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	}
 408out_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 */
 417static 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
 496static 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;
 561out:
 562	mutex_unlock(&lp_mutex);
 563	return ret;
 564}
 565
 566static 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
 580static 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
 667static 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
 699static 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
 709static 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
 723static 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
 751static 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
 785static 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
 813static 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, crlf += written;
 
 
 858			} while (i > 0 && (CONSOLE_LP_STRICT || written > 0));
 859		}
 860	} while (count > 0 && (CONSOLE_LP_STRICT || written > 0));
 861
 862	parport_release(dev);
 863}
 864
 865static struct console lpcons = {
 866	.name		= "lp",
 867	.write		= lp_console_write,
 868	.flags		= CON_PRINTBUFFER,
 869};
 870
 871#endif /* console on line printer */
 872
 873/* --- initialisation code ------------------------------------- */
 874
 875static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
 876static char *parport[LP_NO];
 877static bool reset;
 878
 879module_param_array(parport, charp, NULL, 0);
 880module_param(reset, bool, 0);
 881
 882#ifndef MODULE
 883static int __init lp_setup(char *str)
 884{
 885	static int parport_ptr;
 886	int x;
 887
 888	if (get_option(&str, &x)) {
 889		if (x == 0) {
 890			/* disable driver on "lp=" or "lp=0" */
 891			parport_nr[0] = LP_PARPORT_OFF;
 892		} else {
 893			printk(KERN_WARNING "warning: 'lp=0x%x' is deprecated, ignored\n", x);
 894			return 0;
 895		}
 896	} else if (!strncmp(str, "parport", 7)) {
 897		int n = simple_strtoul(str+7, NULL, 10);
 898		if (parport_ptr < LP_NO)
 899			parport_nr[parport_ptr++] = n;
 900		else
 901			printk(KERN_INFO "lp: too many ports, %s ignored.\n",
 902			       str);
 903	} else if (!strcmp(str, "auto")) {
 904		parport_nr[0] = LP_PARPORT_AUTO;
 905	} else if (!strcmp(str, "none")) {
 906		if (parport_ptr < LP_NO)
 907			parport_nr[parport_ptr++] = LP_PARPORT_NONE;
 908		else
 909			printk(KERN_INFO "lp: too many ports, %s ignored.\n",
 910			       str);
 911	} else if (!strcmp(str, "reset")) {
 912		reset = true;
 913	}
 914	return 1;
 915}
 916#endif
 917
 918static int lp_register(int nr, struct parport *port)
 919{
 920	struct pardev_cb ppdev_cb;
 921
 922	memset(&ppdev_cb, 0, sizeof(ppdev_cb));
 923	ppdev_cb.preempt = lp_preempt;
 924	ppdev_cb.private = &lp_table[nr];
 925	lp_table[nr].dev = parport_register_dev_model(port, "lp",
 926						      &ppdev_cb, nr);
 927	if (lp_table[nr].dev == NULL)
 928		return 1;
 929	lp_table[nr].flags |= LP_EXIST;
 930
 931	if (reset)
 932		lp_reset(nr);
 933
 934	device_create(lp_class, port->dev, MKDEV(LP_MAJOR, nr), NULL,
 935		      "lp%d", nr);
 936
 937	printk(KERN_INFO "lp%d: using %s (%s).\n", nr, port->name,
 938	       (port->irq == PARPORT_IRQ_NONE)?"polling":"interrupt-driven");
 939
 940#ifdef CONFIG_LP_CONSOLE
 941	if (!nr) {
 942		if (port->modes & PARPORT_MODE_SAFEININT) {
 943			register_console(&lpcons);
 944			console_registered = port;
 945			printk(KERN_INFO "lp%d: console ready\n", CONSOLE_LP);
 946		} else
 947			printk(KERN_ERR "lp%d: cannot run console on %s\n",
 948			       CONSOLE_LP, port->name);
 949	}
 950#endif
 951	port_num[nr] = port->number;
 952
 953	return 0;
 954}
 955
 956static void lp_attach(struct parport *port)
 957{
 958	unsigned int i;
 959
 960	switch (parport_nr[0]) {
 961	case LP_PARPORT_UNSPEC:
 962	case LP_PARPORT_AUTO:
 963		if (parport_nr[0] == LP_PARPORT_AUTO &&
 964		    port->probe_info[0].class != PARPORT_CLASS_PRINTER)
 965			return;
 966		if (lp_count == LP_NO) {
 967			printk(KERN_INFO "lp: ignoring parallel port (max. %d)\n",LP_NO);
 968			return;
 969		}
 970		for (i = 0; i < LP_NO; i++)
 971			if (port_num[i] == -1)
 972				break;
 973
 974		if (!lp_register(i, port))
 975			lp_count++;
 976		break;
 977
 978	default:
 979		for (i = 0; i < LP_NO; i++) {
 980			if (port->number == parport_nr[i]) {
 981				if (!lp_register(i, port))
 982					lp_count++;
 983				break;
 984			}
 985		}
 986		break;
 987	}
 988}
 989
 990static void lp_detach(struct parport *port)
 991{
 992	int n;
 993
 994	/* Write this some day. */
 995#ifdef CONFIG_LP_CONSOLE
 996	if (console_registered == port) {
 997		unregister_console(&lpcons);
 998		console_registered = NULL;
 999	}
1000#endif /* CONFIG_LP_CONSOLE */
1001
1002	for (n = 0; n < LP_NO; n++) {
1003		if (port_num[n] == port->number) {
1004			port_num[n] = -1;
1005			lp_count--;
1006			device_destroy(lp_class, MKDEV(LP_MAJOR, n));
1007			parport_unregister_device(lp_table[n].dev);
1008		}
1009	}
1010}
1011
1012static struct parport_driver lp_driver = {
1013	.name = "lp",
1014	.match_port = lp_attach,
1015	.detach = lp_detach,
1016	.devmodel = true,
1017};
1018
1019static int __init lp_init(void)
1020{
1021	int i, err = 0;
1022
1023	if (parport_nr[0] == LP_PARPORT_OFF)
1024		return 0;
1025
1026	for (i = 0; i < LP_NO; i++) {
1027		lp_table[i].dev = NULL;
1028		lp_table[i].flags = 0;
1029		lp_table[i].chars = LP_INIT_CHAR;
1030		lp_table[i].time = LP_INIT_TIME;
1031		lp_table[i].wait = LP_INIT_WAIT;
1032		lp_table[i].lp_buffer = NULL;
1033#ifdef LP_STATS
1034		lp_table[i].lastcall = 0;
1035		lp_table[i].runchars = 0;
1036		memset(&lp_table[i].stats, 0, sizeof(struct lp_stats));
1037#endif
1038		lp_table[i].last_error = 0;
1039		init_waitqueue_head(&lp_table[i].waitq);
1040		init_waitqueue_head(&lp_table[i].dataq);
1041		mutex_init(&lp_table[i].port_mutex);
1042		lp_table[i].timeout = 10 * HZ;
1043		port_num[i] = -1;
1044	}
1045
1046	if (register_chrdev(LP_MAJOR, "lp", &lp_fops)) {
1047		printk(KERN_ERR "lp: unable to get major %d\n", LP_MAJOR);
1048		return -EIO;
1049	}
1050
1051	lp_class = class_create(THIS_MODULE, "printer");
1052	if (IS_ERR(lp_class)) {
1053		err = PTR_ERR(lp_class);
1054		goto out_reg;
1055	}
1056
1057	if (parport_register_driver(&lp_driver)) {
1058		printk(KERN_ERR "lp: unable to register with parport\n");
1059		err = -EIO;
1060		goto out_class;
1061	}
1062
1063	if (!lp_count) {
1064		printk(KERN_INFO "lp: driver loaded but no devices found\n");
1065#ifndef CONFIG_PARPORT_1284
1066		if (parport_nr[0] == LP_PARPORT_AUTO)
1067			printk(KERN_INFO "lp: (is IEEE 1284 support enabled?)\n");
1068#endif
1069	}
1070
1071	return 0;
1072
1073out_class:
1074	class_destroy(lp_class);
1075out_reg:
1076	unregister_chrdev(LP_MAJOR, "lp");
1077	return err;
1078}
1079
1080static int __init lp_init_module(void)
1081{
1082	if (parport[0]) {
1083		/* The user gave some parameters.  Let's see what they were.  */
1084		if (!strncmp(parport[0], "auto", 4))
1085			parport_nr[0] = LP_PARPORT_AUTO;
1086		else {
1087			int n;
1088			for (n = 0; n < LP_NO && parport[n]; n++) {
1089				if (!strncmp(parport[n], "none", 4))
1090					parport_nr[n] = LP_PARPORT_NONE;
1091				else {
1092					char *ep;
1093					unsigned long r = simple_strtoul(parport[n], &ep, 0);
1094					if (ep != parport[n])
1095						parport_nr[n] = r;
1096					else {
1097						printk(KERN_ERR "lp: bad port specifier `%s'\n", parport[n]);
1098						return -ENODEV;
1099					}
1100				}
1101			}
1102		}
1103	}
1104
1105	return lp_init();
1106}
1107
1108static void lp_cleanup_module(void)
1109{
1110	parport_unregister_driver(&lp_driver);
1111
1112#ifdef CONFIG_LP_CONSOLE
1113	unregister_console(&lpcons);
1114#endif
1115
1116	unregister_chrdev(LP_MAJOR, "lp");
1117	class_destroy(lp_class);
1118}
1119
1120__setup("lp=", lp_setup);
1121module_init(lp_init_module);
1122module_exit(lp_cleanup_module);
1123
1124MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
1125MODULE_LICENSE("GPL");