linux/drivers/char/ppdev.c
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   1/*
   2 * linux/drivers/char/ppdev.c
   3 *
   4 * This is the code behind /dev/parport* -- it allows a user-space
   5 * application to use the parport subsystem.
   6 *
   7 * Copyright (C) 1998-2000, 2002 Tim Waugh <tim@cyberelk.net>
   8 *
   9 * This program is free software; you can redistribute it and/or
  10 * modify it under the terms of the GNU General Public License
  11 * as published by the Free Software Foundation; either version
  12 * 2 of the License, or (at your option) any later version.
  13 *
  14 * A /dev/parportx device node represents an arbitrary device
  15 * on port 'x'.  The following operations are possible:
  16 *
  17 * open         do nothing, set up default IEEE 1284 protocol to be COMPAT
  18 * close        release port and unregister device (if necessary)
  19 * ioctl
  20 *   EXCL       register device exclusively (may fail)
  21 *   CLAIM      (register device first time) parport_claim_or_block
  22 *   RELEASE    parport_release
  23 *   SETMODE    set the IEEE 1284 protocol to use for read/write
  24 *   SETPHASE   set the IEEE 1284 phase of a particular mode.  Not to be
  25 *              confused with ioctl(fd, SETPHASER, &stun). ;-)
  26 *   DATADIR    data_forward / data_reverse
  27 *   WDATA      write_data
  28 *   RDATA      read_data
  29 *   WCONTROL   write_control
  30 *   RCONTROL   read_control
  31 *   FCONTROL   frob_control
  32 *   RSTATUS    read_status
  33 *   NEGOT      parport_negotiate
  34 *   YIELD      parport_yield_blocking
  35 *   WCTLONIRQ  on interrupt, set control lines
  36 *   CLRIRQ     clear (and return) interrupt count
  37 *   SETTIME    sets device timeout (struct timeval)
  38 *   GETTIME    gets device timeout (struct timeval)
  39 *   GETMODES   gets hardware supported modes (unsigned int)
  40 *   GETMODE    gets the current IEEE1284 mode
  41 *   GETPHASE   gets the current IEEE1284 phase
  42 *   GETFLAGS   gets current (user-visible) flags
  43 *   SETFLAGS   sets current (user-visible) flags
  44 * read/write   read or write in current IEEE 1284 protocol
  45 * select       wait for interrupt (in readfds)
  46 *
  47 * Changes:
  48 * Added SETTIME/GETTIME ioctl, Fred Barnes, 1999.
  49 *
  50 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 2000/08/25
  51 * - On error, copy_from_user and copy_to_user do not return -EFAULT,
  52 *   They return the positive number of bytes *not* copied due to address
  53 *   space errors.
  54 *
  55 * Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <frmb2@ukc.ac.uk>, 03/01/2001.
  56 * Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001
  57 */
  58
  59#include <linux/module.h>
  60#include <linux/init.h>
  61#include <linux/sched.h>
  62#include <linux/device.h>
  63#include <linux/ioctl.h>
  64#include <linux/parport.h>
  65#include <linux/ctype.h>
  66#include <linux/poll.h>
  67#include <linux/major.h>
  68#include <linux/ppdev.h>
  69#include <linux/smp_lock.h>
  70#include <linux/uaccess.h>
  71
  72#define PP_VERSION "ppdev: user-space parallel port driver"
  73#define CHRDEV "ppdev"
  74
  75struct pp_struct {
  76        struct pardevice * pdev;
  77        wait_queue_head_t irq_wait;
  78        atomic_t irqc;
  79        unsigned int flags;
  80        int irqresponse;
  81        unsigned char irqctl;
  82        struct ieee1284_info state;
  83        struct ieee1284_info saved_state;
  84        long default_inactivity;
  85};
  86
  87/* pp_struct.flags bitfields */
  88#define PP_CLAIMED    (1<<0)
  89#define PP_EXCL       (1<<1)
  90
  91/* Other constants */
  92#define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */
  93#define PP_BUFFER_SIZE 1024
  94#define PARDEVICE_MAX 8
  95
  96/* ROUND_UP macro from fs/select.c */
  97#define ROUND_UP(x,y) (((x)+(y)-1)/(y))
  98
  99static inline void pp_enable_irq (struct pp_struct *pp)
 100{
 101        struct parport *port = pp->pdev->port;
 102        port->ops->enable_irq (port);
 103}
 104
 105static ssize_t pp_read (struct file * file, char __user * buf, size_t count,
 106                        loff_t * ppos)
 107{
 108        unsigned int minor = iminor(file->f_path.dentry->d_inode);
 109        struct pp_struct *pp = file->private_data;
 110        char * kbuffer;
 111        ssize_t bytes_read = 0;
 112        struct parport *pport;
 113        int mode;
 114
 115        if (!(pp->flags & PP_CLAIMED)) {
 116                /* Don't have the port claimed */
 117                printk (KERN_DEBUG CHRDEV "%x: claim the port first\n",
 118                        minor);
 119                return -EINVAL;
 120        }
 121
 122        /* Trivial case. */
 123        if (count == 0)
 124                return 0;
 125
 126        kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
 127        if (!kbuffer) {
 128                return -ENOMEM;
 129        }
 130        pport = pp->pdev->port;
 131        mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
 132
 133        parport_set_timeout (pp->pdev,
 134                             (file->f_flags & O_NONBLOCK) ?
 135                             PARPORT_INACTIVITY_O_NONBLOCK :
 136                             pp->default_inactivity);
 137
 138        while (bytes_read == 0) {
 139                ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE);
 140
 141                if (mode == IEEE1284_MODE_EPP) {
 142                        /* various specials for EPP mode */
 143                        int flags = 0;
 144                        size_t (*fn)(struct parport *, void *, size_t, int);
 145
 146                        if (pp->flags & PP_W91284PIC) {
 147                                flags |= PARPORT_W91284PIC;
 148                        }
 149                        if (pp->flags & PP_FASTREAD) {
 150                                flags |= PARPORT_EPP_FAST;
 151                        }
 152                        if (pport->ieee1284.mode & IEEE1284_ADDR) {
 153                                fn = pport->ops->epp_read_addr;
 154                        } else {
 155                                fn = pport->ops->epp_read_data;
 156                        }
 157                        bytes_read = (*fn)(pport, kbuffer, need, flags);
 158                } else {
 159                        bytes_read = parport_read (pport, kbuffer, need);
 160                }
 161
 162                if (bytes_read != 0)
 163                        break;
 164
 165                if (file->f_flags & O_NONBLOCK) {
 166                        bytes_read = -EAGAIN;
 167                        break;
 168                }
 169
 170                if (signal_pending (current)) {
 171                        bytes_read = -ERESTARTSYS;
 172                        break;
 173                }
 174
 175                cond_resched();
 176        }
 177
 178        parport_set_timeout (pp->pdev, pp->default_inactivity);
 179
 180        if (bytes_read > 0 && copy_to_user (buf, kbuffer, bytes_read))
 181                bytes_read = -EFAULT;
 182
 183        kfree (kbuffer);
 184        pp_enable_irq (pp);
 185        return bytes_read;
 186}
 187
 188static ssize_t pp_write (struct file * file, const char __user * buf,
 189                         size_t count, loff_t * ppos)
 190{
 191        unsigned int minor = iminor(file->f_path.dentry->d_inode);
 192        struct pp_struct *pp = file->private_data;
 193        char * kbuffer;
 194        ssize_t bytes_written = 0;
 195        ssize_t wrote;
 196        int mode;
 197        struct parport *pport;
 198
 199        if (!(pp->flags & PP_CLAIMED)) {
 200                /* Don't have the port claimed */
 201                printk (KERN_DEBUG CHRDEV "%x: claim the port first\n",
 202                        minor);
 203                return -EINVAL;
 204        }
 205
 206        kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL);
 207        if (!kbuffer) {
 208                return -ENOMEM;
 209        }
 210        pport = pp->pdev->port;
 211        mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR);
 212
 213        parport_set_timeout (pp->pdev,
 214                             (file->f_flags & O_NONBLOCK) ?
 215                             PARPORT_INACTIVITY_O_NONBLOCK :
 216                             pp->default_inactivity);
 217
 218        while (bytes_written < count) {
 219                ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE);
 220
 221                if (copy_from_user (kbuffer, buf + bytes_written, n)) {
 222                        bytes_written = -EFAULT;
 223                        break;
 224                }
 225
 226                if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) {
 227                        /* do a fast EPP write */
 228                        if (pport->ieee1284.mode & IEEE1284_ADDR) {
 229                                wrote = pport->ops->epp_write_addr (pport,
 230                                        kbuffer, n, PARPORT_EPP_FAST);
 231                        } else {
 232                                wrote = pport->ops->epp_write_data (pport,
 233                                        kbuffer, n, PARPORT_EPP_FAST);
 234                        }
 235                } else {
 236                        wrote = parport_write (pp->pdev->port, kbuffer, n);
 237                }
 238
 239                if (wrote <= 0) {
 240                        if (!bytes_written) {
 241                                bytes_written = wrote;
 242                        }
 243                        break;
 244                }
 245
 246                bytes_written += wrote;
 247
 248                if (file->f_flags & O_NONBLOCK) {
 249                        if (!bytes_written)
 250                                bytes_written = -EAGAIN;
 251                        break;
 252                }
 253
 254                if (signal_pending (current)) {
 255                        if (!bytes_written) {
 256                                bytes_written = -EINTR;
 257                        }
 258                        break;
 259                }
 260
 261                cond_resched();
 262        }
 263
 264        parport_set_timeout (pp->pdev, pp->default_inactivity);
 265
 266        kfree (kbuffer);
 267        pp_enable_irq (pp);
 268        return bytes_written;
 269}
 270
 271static void pp_irq (void *private)
 272{
 273        struct pp_struct *pp = private;
 274
 275        if (pp->irqresponse) {
 276                parport_write_control (pp->pdev->port, pp->irqctl);
 277                pp->irqresponse = 0;
 278        }
 279
 280        atomic_inc (&pp->irqc);
 281        wake_up_interruptible (&pp->irq_wait);
 282}
 283
 284static int register_device (int minor, struct pp_struct *pp)
 285{
 286        struct parport *port;
 287        struct pardevice * pdev = NULL;
 288        char *name;
 289        int fl;
 290
 291        name = kmalloc (strlen (CHRDEV) + 3, GFP_KERNEL);
 292        if (name == NULL)
 293                return -ENOMEM;
 294
 295        sprintf (name, CHRDEV "%x", minor);
 296
 297        port = parport_find_number (minor);
 298        if (!port) {
 299                printk (KERN_WARNING "%s: no associated port!\n", name);
 300                kfree (name);
 301                return -ENXIO;
 302        }
 303
 304        fl = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0;
 305        pdev = parport_register_device (port, name, NULL,
 306                                        NULL, pp_irq, fl, pp);
 307        parport_put_port (port);
 308
 309        if (!pdev) {
 310                printk (KERN_WARNING "%s: failed to register device!\n", name);
 311                kfree (name);
 312                return -ENXIO;
 313        }
 314
 315        pp->pdev = pdev;
 316        printk (KERN_DEBUG "%s: registered pardevice\n", name);
 317        return 0;
 318}
 319
 320static enum ieee1284_phase init_phase (int mode)
 321{
 322        switch (mode & ~(IEEE1284_DEVICEID
 323                         | IEEE1284_ADDR)) {
 324        case IEEE1284_MODE_NIBBLE:
 325        case IEEE1284_MODE_BYTE:
 326                return IEEE1284_PH_REV_IDLE;
 327        }
 328        return IEEE1284_PH_FWD_IDLE;
 329}
 330
 331static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 332{
 333        unsigned int minor = iminor(file->f_path.dentry->d_inode);
 334        struct pp_struct *pp = file->private_data;
 335        struct parport * port;
 336        void __user *argp = (void __user *)arg;
 337
 338        /* First handle the cases that don't take arguments. */
 339        switch (cmd) {
 340        case PPCLAIM:
 341            {
 342                struct ieee1284_info *info;
 343                int ret;
 344
 345                if (pp->flags & PP_CLAIMED) {
 346                        printk (KERN_DEBUG CHRDEV
 347                                "%x: you've already got it!\n", minor);
 348                        return -EINVAL;
 349                }
 350
 351                /* Deferred device registration. */
 352                if (!pp->pdev) {
 353                        int err = register_device (minor, pp);
 354                        if (err) {
 355                                return err;
 356                        }
 357                }
 358
 359                ret = parport_claim_or_block (pp->pdev);
 360                if (ret < 0)
 361                        return ret;
 362
 363                pp->flags |= PP_CLAIMED;
 364
 365                /* For interrupt-reporting to work, we need to be
 366                 * informed of each interrupt. */
 367                pp_enable_irq (pp);
 368
 369                /* We may need to fix up the state machine. */
 370                info = &pp->pdev->port->ieee1284;
 371                pp->saved_state.mode = info->mode;
 372                pp->saved_state.phase = info->phase;
 373                info->mode = pp->state.mode;
 374                info->phase = pp->state.phase;
 375                pp->default_inactivity = parport_set_timeout (pp->pdev, 0);
 376                parport_set_timeout (pp->pdev, pp->default_inactivity);
 377
 378                return 0;
 379            }
 380        case PPEXCL:
 381                if (pp->pdev) {
 382                        printk (KERN_DEBUG CHRDEV "%x: too late for PPEXCL; "
 383                                "already registered\n", minor);
 384                        if (pp->flags & PP_EXCL)
 385                                /* But it's not really an error. */
 386                                return 0;
 387                        /* There's no chance of making the driver happy. */
 388                        return -EINVAL;
 389                }
 390
 391                /* Just remember to register the device exclusively
 392                 * when we finally do the registration. */
 393                pp->flags |= PP_EXCL;
 394                return 0;
 395        case PPSETMODE:
 396            {
 397                int mode;
 398                if (copy_from_user (&mode, argp, sizeof (mode)))
 399                        return -EFAULT;
 400                /* FIXME: validate mode */
 401                pp->state.mode = mode;
 402                pp->state.phase = init_phase (mode);
 403
 404                if (pp->flags & PP_CLAIMED) {
 405                        pp->pdev->port->ieee1284.mode = mode;
 406                        pp->pdev->port->ieee1284.phase = pp->state.phase;
 407                }
 408
 409                return 0;
 410            }
 411        case PPGETMODE:
 412            {
 413                int mode;
 414
 415                if (pp->flags & PP_CLAIMED) {
 416                        mode = pp->pdev->port->ieee1284.mode;
 417                } else {
 418                        mode = pp->state.mode;
 419                }
 420                if (copy_to_user (argp, &mode, sizeof (mode))) {
 421                        return -EFAULT;
 422                }
 423                return 0;
 424            }
 425        case PPSETPHASE:
 426            {
 427                int phase;
 428                if (copy_from_user (&phase, argp, sizeof (phase))) {
 429                        return -EFAULT;
 430                }
 431                /* FIXME: validate phase */
 432                pp->state.phase = phase;
 433
 434                if (pp->flags & PP_CLAIMED) {
 435                        pp->pdev->port->ieee1284.phase = phase;
 436                }
 437
 438                return 0;
 439            }
 440        case PPGETPHASE:
 441            {
 442                int phase;
 443
 444                if (pp->flags & PP_CLAIMED) {
 445                        phase = pp->pdev->port->ieee1284.phase;
 446                } else {
 447                        phase = pp->state.phase;
 448                }
 449                if (copy_to_user (argp, &phase, sizeof (phase))) {
 450                        return -EFAULT;
 451                }
 452                return 0;
 453            }
 454        case PPGETMODES:
 455            {
 456                unsigned int modes;
 457
 458                port = parport_find_number (minor);
 459                if (!port)
 460                        return -ENODEV;
 461
 462                modes = port->modes;
 463                if (copy_to_user (argp, &modes, sizeof (modes))) {
 464                        return -EFAULT;
 465                }
 466                return 0;
 467            }
 468        case PPSETFLAGS:
 469            {
 470                int uflags;
 471
 472                if (copy_from_user (&uflags, argp, sizeof (uflags))) {
 473                        return -EFAULT;
 474                }
 475                pp->flags &= ~PP_FLAGMASK;
 476                pp->flags |= (uflags & PP_FLAGMASK);
 477                return 0;
 478            }
 479        case PPGETFLAGS:
 480            {
 481                int uflags;
 482
 483                uflags = pp->flags & PP_FLAGMASK;
 484                if (copy_to_user (argp, &uflags, sizeof (uflags))) {
 485                        return -EFAULT;
 486                }
 487                return 0;
 488            }
 489        }       /* end switch() */
 490
 491        /* Everything else requires the port to be claimed, so check
 492         * that now. */
 493        if ((pp->flags & PP_CLAIMED) == 0) {
 494                printk (KERN_DEBUG CHRDEV "%x: claim the port first\n",
 495                        minor);
 496                return -EINVAL;
 497        }
 498
 499        port = pp->pdev->port;
 500        switch (cmd) {
 501                struct ieee1284_info *info;
 502                unsigned char reg;
 503                unsigned char mask;
 504                int mode;
 505                int ret;
 506                struct timeval par_timeout;
 507                long to_jiffies;
 508
 509        case PPRSTATUS:
 510                reg = parport_read_status (port);
 511                if (copy_to_user (argp, &reg, sizeof (reg)))
 512                        return -EFAULT;
 513                return 0;
 514        case PPRDATA:
 515                reg = parport_read_data (port);
 516                if (copy_to_user (argp, &reg, sizeof (reg)))
 517                        return -EFAULT;
 518                return 0;
 519        case PPRCONTROL:
 520                reg = parport_read_control (port);
 521                if (copy_to_user (argp, &reg, sizeof (reg)))
 522                        return -EFAULT;
 523                return 0;
 524        case PPYIELD:
 525                parport_yield_blocking (pp->pdev);
 526                return 0;
 527
 528        case PPRELEASE:
 529                /* Save the state machine's state. */
 530                info = &pp->pdev->port->ieee1284;
 531                pp->state.mode = info->mode;
 532                pp->state.phase = info->phase;
 533                info->mode = pp->saved_state.mode;
 534                info->phase = pp->saved_state.phase;
 535                parport_release (pp->pdev);
 536                pp->flags &= ~PP_CLAIMED;
 537                return 0;
 538
 539        case PPWCONTROL:
 540                if (copy_from_user (&reg, argp, sizeof (reg)))
 541                        return -EFAULT;
 542                parport_write_control (port, reg);
 543                return 0;
 544
 545        case PPWDATA:
 546                if (copy_from_user (&reg, argp, sizeof (reg)))
 547                        return -EFAULT;
 548                parport_write_data (port, reg);
 549                return 0;
 550
 551        case PPFCONTROL:
 552                if (copy_from_user (&mask, argp,
 553                                    sizeof (mask)))
 554                        return -EFAULT;
 555                if (copy_from_user (&reg, 1 + (unsigned char __user *) arg,
 556                                    sizeof (reg)))
 557                        return -EFAULT;
 558                parport_frob_control (port, mask, reg);
 559                return 0;
 560
 561        case PPDATADIR:
 562                if (copy_from_user (&mode, argp, sizeof (mode)))
 563                        return -EFAULT;
 564                if (mode)
 565                        port->ops->data_reverse (port);
 566                else
 567                        port->ops->data_forward (port);
 568                return 0;
 569
 570        case PPNEGOT:
 571                if (copy_from_user (&mode, argp, sizeof (mode)))
 572                        return -EFAULT;
 573                switch ((ret = parport_negotiate (port, mode))) {
 574                case 0: break;
 575                case -1: /* handshake failed, peripheral not IEEE 1284 */
 576                        ret = -EIO;
 577                        break;
 578                case 1:  /* handshake succeeded, peripheral rejected mode */
 579                        ret = -ENXIO;
 580                        break;
 581                }
 582                pp_enable_irq (pp);
 583                return ret;
 584
 585        case PPWCTLONIRQ:
 586                if (copy_from_user (&reg, argp, sizeof (reg)))
 587                        return -EFAULT;
 588
 589                /* Remember what to set the control lines to, for next
 590                 * time we get an interrupt. */
 591                pp->irqctl = reg;
 592                pp->irqresponse = 1;
 593                return 0;
 594
 595        case PPCLRIRQ:
 596                ret = atomic_read (&pp->irqc);
 597                if (copy_to_user (argp, &ret, sizeof (ret)))
 598                        return -EFAULT;
 599                atomic_sub (ret, &pp->irqc);
 600                return 0;
 601
 602        case PPSETTIME:
 603                if (copy_from_user (&par_timeout, argp, sizeof(struct timeval))) {
 604                        return -EFAULT;
 605                }
 606                /* Convert to jiffies, place in pp->pdev->timeout */
 607                if ((par_timeout.tv_sec < 0) || (par_timeout.tv_usec < 0)) {
 608                        return -EINVAL;
 609                }
 610                to_jiffies = ROUND_UP(par_timeout.tv_usec, 1000000/HZ);
 611                to_jiffies += par_timeout.tv_sec * (long)HZ;
 612                if (to_jiffies <= 0) {
 613                        return -EINVAL;
 614                }
 615                pp->pdev->timeout = to_jiffies;
 616                return 0;
 617
 618        case PPGETTIME:
 619                to_jiffies = pp->pdev->timeout;
 620                par_timeout.tv_sec = to_jiffies / HZ;
 621                par_timeout.tv_usec = (to_jiffies % (long)HZ) * (1000000/HZ);
 622                if (copy_to_user (argp, &par_timeout, sizeof(struct timeval)))
 623                        return -EFAULT;
 624                return 0;
 625
 626        default:
 627                printk (KERN_DEBUG CHRDEV "%x: What? (cmd=0x%x)\n", minor,
 628                        cmd);
 629                return -EINVAL;
 630        }
 631
 632        /* Keep the compiler happy */
 633        return 0;
 634}
 635
 636static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 637{
 638        long ret;
 639        lock_kernel();
 640        ret = pp_do_ioctl(file, cmd, arg);
 641        unlock_kernel();
 642        return ret;
 643}
 644
 645static int pp_open (struct inode * inode, struct file * file)
 646{
 647        unsigned int minor = iminor(inode);
 648        struct pp_struct *pp;
 649
 650        cycle_kernel_lock();
 651        if (minor >= PARPORT_MAX)
 652                return -ENXIO;
 653
 654        pp = kmalloc (sizeof (struct pp_struct), GFP_KERNEL);
 655        if (!pp)
 656                return -ENOMEM;
 657
 658        pp->state.mode = IEEE1284_MODE_COMPAT;
 659        pp->state.phase = init_phase (pp->state.mode);
 660        pp->flags = 0;
 661        pp->irqresponse = 0;
 662        atomic_set (&pp->irqc, 0);
 663        init_waitqueue_head (&pp->irq_wait);
 664
 665        /* Defer the actual device registration until the first claim.
 666         * That way, we know whether or not the driver wants to have
 667         * exclusive access to the port (PPEXCL).
 668         */
 669        pp->pdev = NULL;
 670        file->private_data = pp;
 671
 672        return 0;
 673}
 674
 675static int pp_release (struct inode * inode, struct file * file)
 676{
 677        unsigned int minor = iminor(inode);
 678        struct pp_struct *pp = file->private_data;
 679        int compat_negot;
 680
 681        compat_negot = 0;
 682        if (!(pp->flags & PP_CLAIMED) && pp->pdev &&
 683            (pp->state.mode != IEEE1284_MODE_COMPAT)) {
 684                struct ieee1284_info *info;
 685
 686                /* parport released, but not in compatibility mode */
 687                parport_claim_or_block (pp->pdev);
 688                pp->flags |= PP_CLAIMED;
 689                info = &pp->pdev->port->ieee1284;
 690                pp->saved_state.mode = info->mode;
 691                pp->saved_state.phase = info->phase;
 692                info->mode = pp->state.mode;
 693                info->phase = pp->state.phase;
 694                compat_negot = 1;
 695        } else if ((pp->flags & PP_CLAIMED) && pp->pdev &&
 696            (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) {
 697                compat_negot = 2;
 698        }
 699        if (compat_negot) {
 700                parport_negotiate (pp->pdev->port, IEEE1284_MODE_COMPAT);
 701                printk (KERN_DEBUG CHRDEV
 702                        "%x: negotiated back to compatibility mode because "
 703                        "user-space forgot\n", minor);
 704        }
 705
 706        if (pp->flags & PP_CLAIMED) {
 707                struct ieee1284_info *info;
 708
 709                info = &pp->pdev->port->ieee1284;
 710                pp->state.mode = info->mode;
 711                pp->state.phase = info->phase;
 712                info->mode = pp->saved_state.mode;
 713                info->phase = pp->saved_state.phase;
 714                parport_release (pp->pdev);
 715                if (compat_negot != 1) {
 716                        printk (KERN_DEBUG CHRDEV "%x: released pardevice "
 717                                "because user-space forgot\n", minor);
 718                }
 719        }
 720
 721        if (pp->pdev) {
 722                const char *name = pp->pdev->name;
 723                parport_unregister_device (pp->pdev);
 724                kfree (name);
 725                pp->pdev = NULL;
 726                printk (KERN_DEBUG CHRDEV "%x: unregistered pardevice\n",
 727                        minor);
 728        }
 729
 730        kfree (pp);
 731
 732        return 0;
 733}
 734
 735/* No kernel lock held - fine */
 736static unsigned int pp_poll (struct file * file, poll_table * wait)
 737{
 738        struct pp_struct *pp = file->private_data;
 739        unsigned int mask = 0;
 740
 741        poll_wait (file, &pp->irq_wait, wait);
 742        if (atomic_read (&pp->irqc))
 743                mask |= POLLIN | POLLRDNORM;
 744
 745        return mask;
 746}
 747
 748static struct class *ppdev_class;
 749
 750static const struct file_operations pp_fops = {
 751        .owner          = THIS_MODULE,
 752        .llseek         = no_llseek,
 753        .read           = pp_read,
 754        .write          = pp_write,
 755        .poll           = pp_poll,
 756        .unlocked_ioctl = pp_ioctl,
 757        .open           = pp_open,
 758        .release        = pp_release,
 759};
 760
 761static void pp_attach(struct parport *port)
 762{
 763        device_create(ppdev_class, port->dev, MKDEV(PP_MAJOR, port->number),
 764                      NULL, "parport%d", port->number);
 765}
 766
 767static void pp_detach(struct parport *port)
 768{
 769        device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number));
 770}
 771
 772static struct parport_driver pp_driver = {
 773        .name           = CHRDEV,
 774        .attach         = pp_attach,
 775        .detach         = pp_detach,
 776};
 777
 778static int __init ppdev_init (void)
 779{
 780        int err = 0;
 781
 782        if (register_chrdev (PP_MAJOR, CHRDEV, &pp_fops)) {
 783                printk (KERN_WARNING CHRDEV ": unable to get major %d\n",
 784                        PP_MAJOR);
 785                return -EIO;
 786        }
 787        ppdev_class = class_create(THIS_MODULE, CHRDEV);
 788        if (IS_ERR(ppdev_class)) {
 789                err = PTR_ERR(ppdev_class);
 790                goto out_chrdev;
 791        }
 792        if (parport_register_driver(&pp_driver)) {
 793                printk (KERN_WARNING CHRDEV ": unable to register with parport\n");
 794                goto out_class;
 795        }
 796
 797        printk (KERN_INFO PP_VERSION "\n");
 798        goto out;
 799
 800out_class:
 801        class_destroy(ppdev_class);
 802out_chrdev:
 803        unregister_chrdev(PP_MAJOR, CHRDEV);
 804out:
 805        return err;
 806}
 807
 808static void __exit ppdev_cleanup (void)
 809{
 810        /* Clean up all parport stuff */
 811        parport_unregister_driver(&pp_driver);
 812        class_destroy(ppdev_class);
 813        unregister_chrdev (PP_MAJOR, CHRDEV);
 814}
 815
 816module_init(ppdev_init);
 817module_exit(ppdev_cleanup);
 818
 819MODULE_LICENSE("GPL");
 820MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR);
 821
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