linux/drivers/char/lp.c
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   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;
 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
 867static 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
 877static int parport_nr[LP_NO] = { [0 ... LP_NO-1] = LP_PARPORT_UNSPEC };
 878static char *parport[LP_NO];
 879static bool reset;
 880
 881module_param_array(parport, charp, NULL, 0);
 882module_param(reset, bool, 0);
 883
 884#ifndef MODULE
 885static 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
 920static 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
 958static 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
 992static 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
1014static struct parport_driver lp_driver = {
1015        .name = "lp",
1016        .match_port = lp_attach,
1017        .detach = lp_detach,
1018        .devmodel = true,
1019};
1020
1021static 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
1075out_class:
1076        class_destroy(lp_class);
1077out_reg:
1078        unregister_chrdev(LP_MAJOR, "lp");
1079        return err;
1080}
1081
1082static 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
1110static 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);
1123module_init(lp_init_module);
1124module_exit(lp_cleanup_module);
1125
1126MODULE_ALIAS_CHARDEV_MAJOR(LP_MAJOR);
1127MODULE_LICENSE("GPL");
1128