1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * linux/drivers/char/ppdev.c 4 * 5 * This is the code behind /dev/parport* -- it allows a user-space 6 * application to use the parport subsystem. 7 * 8 * Copyright (C) 1998-2000, 2002 Tim Waugh <tim@cyberelk.net> 9 * 10 * A /dev/parportx device node represents an arbitrary device 11 * on port 'x'. The following operations are possible: 12 * 13 * open do nothing, set up default IEEE 1284 protocol to be COMPAT 14 * close release port and unregister device (if necessary) 15 * ioctl 16 * EXCL register device exclusively (may fail) 17 * CLAIM (register device first time) parport_claim_or_block 18 * RELEASE parport_release 19 * SETMODE set the IEEE 1284 protocol to use for read/write 20 * SETPHASE set the IEEE 1284 phase of a particular mode. Not to be 21 * confused with ioctl(fd, SETPHASER, &stun). ;-) 22 * DATADIR data_forward / data_reverse 23 * WDATA write_data 24 * RDATA read_data 25 * WCONTROL write_control 26 * RCONTROL read_control 27 * FCONTROL frob_control 28 * RSTATUS read_status 29 * NEGOT parport_negotiate 30 * YIELD parport_yield_blocking 31 * WCTLONIRQ on interrupt, set control lines 32 * CLRIRQ clear (and return) interrupt count 33 * SETTIME sets device timeout (struct timeval) 34 * GETTIME gets device timeout (struct timeval) 35 * GETMODES gets hardware supported modes (unsigned int) 36 * GETMODE gets the current IEEE1284 mode 37 * GETPHASE gets the current IEEE1284 phase 38 * GETFLAGS gets current (user-visible) flags 39 * SETFLAGS sets current (user-visible) flags 40 * read/write read or write in current IEEE 1284 protocol 41 * select wait for interrupt (in readfds) 42 * 43 * Changes: 44 * Added SETTIME/GETTIME ioctl, Fred Barnes, 1999. 45 * 46 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 2000/08/25 47 * - On error, copy_from_user and copy_to_user do not return -EFAULT, 48 * They return the positive number of bytes *not* copied due to address 49 * space errors. 50 * 51 * Added GETMODES/GETMODE/GETPHASE ioctls, Fred Barnes <frmb2@ukc.ac.uk>, 03/01/2001. 52 * Added GETFLAGS/SETFLAGS ioctls, Fred Barnes, 04/2001 53 */ 54 55 #include <linux/module.h> 56 #include <linux/init.h> 57 #include <linux/sched/signal.h> 58 #include <linux/device.h> 59 #include <linux/ioctl.h> 60 #include <linux/parport.h> 61 #include <linux/ctype.h> 62 #include <linux/poll.h> 63 #include <linux/slab.h> 64 #include <linux/major.h> 65 #include <linux/ppdev.h> 66 #include <linux/mutex.h> 67 #include <linux/uaccess.h> 68 #include <linux/compat.h> 69 70 #define PP_VERSION "ppdev: user-space parallel port driver" 71 #define CHRDEV "ppdev" 72 73 struct pp_struct { 74 struct pardevice *pdev; 75 wait_queue_head_t irq_wait; 76 atomic_t irqc; 77 unsigned int flags; 78 int irqresponse; 79 unsigned char irqctl; 80 struct ieee1284_info state; 81 struct ieee1284_info saved_state; 82 long default_inactivity; 83 int index; 84 }; 85 86 /* should we use PARDEVICE_MAX here? */ 87 static struct device *devices[PARPORT_MAX]; 88 89 static DEFINE_IDA(ida_index); 90 91 /* pp_struct.flags bitfields */ 92 #define PP_CLAIMED (1<<0) 93 #define PP_EXCL (1<<1) 94 95 /* Other constants */ 96 #define PP_INTERRUPT_TIMEOUT (10 * HZ) /* 10s */ 97 #define PP_BUFFER_SIZE 1024 98 #define PARDEVICE_MAX 8 99 100 static DEFINE_MUTEX(pp_do_mutex); 101 102 /* define fixed sized ioctl cmd for y2038 migration */ 103 #define PPGETTIME32 _IOR(PP_IOCTL, 0x95, s32[2]) 104 #define PPSETTIME32 _IOW(PP_IOCTL, 0x96, s32[2]) 105 #define PPGETTIME64 _IOR(PP_IOCTL, 0x95, s64[2]) 106 #define PPSETTIME64 _IOW(PP_IOCTL, 0x96, s64[2]) 107 108 static inline void pp_enable_irq(struct pp_struct *pp) 109 { 110 struct parport *port = pp->pdev->port; 111 112 port->ops->enable_irq(port); 113 } 114 115 static ssize_t pp_read(struct file *file, char __user *buf, size_t count, 116 loff_t *ppos) 117 { 118 unsigned int minor = iminor(file_inode(file)); 119 struct pp_struct *pp = file->private_data; 120 char *kbuffer; 121 ssize_t bytes_read = 0; 122 struct parport *pport; 123 int mode; 124 125 if (!(pp->flags & PP_CLAIMED)) { 126 /* Don't have the port claimed */ 127 pr_debug(CHRDEV "%x: claim the port first\n", minor); 128 return -EINVAL; 129 } 130 131 /* Trivial case. */ 132 if (count == 0) 133 return 0; 134 135 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL); 136 if (!kbuffer) 137 return -ENOMEM; 138 pport = pp->pdev->port; 139 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR); 140 141 parport_set_timeout(pp->pdev, 142 (file->f_flags & O_NONBLOCK) ? 143 PARPORT_INACTIVITY_O_NONBLOCK : 144 pp->default_inactivity); 145 146 while (bytes_read == 0) { 147 ssize_t need = min_t(unsigned long, count, PP_BUFFER_SIZE); 148 149 if (mode == IEEE1284_MODE_EPP) { 150 /* various specials for EPP mode */ 151 int flags = 0; 152 size_t (*fn)(struct parport *, void *, size_t, int); 153 154 if (pp->flags & PP_W91284PIC) 155 flags |= PARPORT_W91284PIC; 156 if (pp->flags & PP_FASTREAD) 157 flags |= PARPORT_EPP_FAST; 158 if (pport->ieee1284.mode & IEEE1284_ADDR) 159 fn = pport->ops->epp_read_addr; 160 else 161 fn = pport->ops->epp_read_data; 162 bytes_read = (*fn)(pport, kbuffer, need, flags); 163 } else { 164 bytes_read = parport_read(pport, kbuffer, need); 165 } 166 167 if (bytes_read != 0) 168 break; 169 170 if (file->f_flags & O_NONBLOCK) { 171 bytes_read = -EAGAIN; 172 break; 173 } 174 175 if (signal_pending(current)) { 176 bytes_read = -ERESTARTSYS; 177 break; 178 } 179 180 cond_resched(); 181 } 182 183 parport_set_timeout(pp->pdev, pp->default_inactivity); 184 185 if (bytes_read > 0 && copy_to_user(buf, kbuffer, bytes_read)) 186 bytes_read = -EFAULT; 187 188 kfree(kbuffer); 189 pp_enable_irq(pp); 190 return bytes_read; 191 } 192 193 static ssize_t pp_write(struct file *file, const char __user *buf, 194 size_t count, loff_t *ppos) 195 { 196 unsigned int minor = iminor(file_inode(file)); 197 struct pp_struct *pp = file->private_data; 198 char *kbuffer; 199 ssize_t bytes_written = 0; 200 ssize_t wrote; 201 int mode; 202 struct parport *pport; 203 204 if (!(pp->flags & PP_CLAIMED)) { 205 /* Don't have the port claimed */ 206 pr_debug(CHRDEV "%x: claim the port first\n", minor); 207 return -EINVAL; 208 } 209 210 kbuffer = kmalloc(min_t(size_t, count, PP_BUFFER_SIZE), GFP_KERNEL); 211 if (!kbuffer) 212 return -ENOMEM; 213 214 pport = pp->pdev->port; 215 mode = pport->ieee1284.mode & ~(IEEE1284_DEVICEID | IEEE1284_ADDR); 216 217 parport_set_timeout(pp->pdev, 218 (file->f_flags & O_NONBLOCK) ? 219 PARPORT_INACTIVITY_O_NONBLOCK : 220 pp->default_inactivity); 221 222 while (bytes_written < count) { 223 ssize_t n = min_t(unsigned long, count - bytes_written, PP_BUFFER_SIZE); 224 225 if (copy_from_user(kbuffer, buf + bytes_written, n)) { 226 bytes_written = -EFAULT; 227 break; 228 } 229 230 if ((pp->flags & PP_FASTWRITE) && (mode == IEEE1284_MODE_EPP)) { 231 /* do a fast EPP write */ 232 if (pport->ieee1284.mode & IEEE1284_ADDR) { 233 wrote = pport->ops->epp_write_addr(pport, 234 kbuffer, n, PARPORT_EPP_FAST); 235 } else { 236 wrote = pport->ops->epp_write_data(pport, 237 kbuffer, n, PARPORT_EPP_FAST); 238 } 239 } else { 240 wrote = parport_write(pp->pdev->port, kbuffer, n); 241 } 242 243 if (wrote <= 0) { 244 if (!bytes_written) 245 bytes_written = wrote; 246 break; 247 } 248 249 bytes_written += wrote; 250 251 if (file->f_flags & O_NONBLOCK) { 252 if (!bytes_written) 253 bytes_written = -EAGAIN; 254 break; 255 } 256 257 if (signal_pending(current)) 258 break; 259 260 cond_resched(); 261 } 262 263 parport_set_timeout(pp->pdev, pp->default_inactivity); 264 265 kfree(kbuffer); 266 pp_enable_irq(pp); 267 return bytes_written; 268 } 269 270 static void pp_irq(void *private) 271 { 272 struct pp_struct *pp = private; 273 274 if (pp->irqresponse) { 275 parport_write_control(pp->pdev->port, pp->irqctl); 276 pp->irqresponse = 0; 277 } 278 279 atomic_inc(&pp->irqc); 280 wake_up_interruptible(&pp->irq_wait); 281 } 282 283 static int register_device(int minor, struct pp_struct *pp) 284 { 285 struct parport *port; 286 struct pardevice *pdev = NULL; 287 char *name; 288 struct pardev_cb ppdev_cb; 289 int rc = 0, index; 290 291 name = kasprintf(GFP_KERNEL, CHRDEV "%x", minor); 292 if (name == NULL) 293 return -ENOMEM; 294 295 port = parport_find_number(minor); 296 if (!port) { 297 pr_warn("%s: no associated port!\n", name); 298 rc = -ENXIO; 299 goto err_free_name; 300 } 301 302 index = ida_alloc(&ida_index, GFP_KERNEL); 303 if (index < 0) { 304 pr_warn("%s: failed to get index!\n", name); 305 rc = index; 306 goto err_put_port; 307 } 308 309 memset(&ppdev_cb, 0, sizeof(ppdev_cb)); 310 ppdev_cb.irq_func = pp_irq; 311 ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0; 312 ppdev_cb.private = pp; 313 pdev = parport_register_dev_model(port, name, &ppdev_cb, index); 314 315 if (!pdev) { 316 pr_warn("%s: failed to register device!\n", name); 317 rc = -ENXIO; 318 ida_free(&ida_index, index); 319 goto err_put_port; 320 } 321 322 pp->pdev = pdev; 323 pp->index = index; 324 dev_dbg(&pdev->dev, "registered pardevice\n"); 325 err_put_port: 326 parport_put_port(port); 327 err_free_name: 328 kfree(name); 329 return rc; 330 } 331 332 static enum ieee1284_phase init_phase(int mode) 333 { 334 switch (mode & ~(IEEE1284_DEVICEID 335 | IEEE1284_ADDR)) { 336 case IEEE1284_MODE_NIBBLE: 337 case IEEE1284_MODE_BYTE: 338 return IEEE1284_PH_REV_IDLE; 339 } 340 return IEEE1284_PH_FWD_IDLE; 341 } 342 343 static int pp_set_timeout(struct pardevice *pdev, s64 tv_sec, s64 tv_usec) 344 { 345 struct timespec64 ts; 346 long to_jiffies; 347 348 if (tv_sec < 0 || tv_usec < 0 || tv_usec >= USEC_PER_SEC) 349 return -EINVAL; 350 351 ts.tv_sec = tv_sec; 352 ts.tv_nsec = tv_usec * NSEC_PER_USEC; 353 to_jiffies = timespec64_to_jiffies(&ts); 354 if (to_jiffies <= 0) 355 return -EINVAL; 356 357 pdev->timeout = to_jiffies; 358 return 0; 359 } 360 361 static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 362 { 363 unsigned int minor = iminor(file_inode(file)); 364 struct pp_struct *pp = file->private_data; 365 struct parport *port; 366 void __user *argp = (void __user *)arg; 367 struct ieee1284_info *info; 368 unsigned char reg; 369 unsigned char mask; 370 int mode; 371 s32 time32[2]; 372 s64 time64[2]; 373 struct timespec64 ts; 374 int ret; 375 376 /* First handle the cases that don't take arguments. */ 377 switch (cmd) { 378 case PPCLAIM: 379 { 380 if (pp->flags & PP_CLAIMED) { 381 dev_dbg(&pp->pdev->dev, "you've already got it!\n"); 382 return -EINVAL; 383 } 384 385 /* Deferred device registration. */ 386 if (!pp->pdev) { 387 int err = register_device(minor, pp); 388 389 if (err) 390 return err; 391 } 392 393 ret = parport_claim_or_block(pp->pdev); 394 if (ret < 0) 395 return ret; 396 397 pp->flags |= PP_CLAIMED; 398 399 /* For interrupt-reporting to work, we need to be 400 * informed of each interrupt. */ 401 pp_enable_irq(pp); 402 403 /* We may need to fix up the state machine. */ 404 info = &pp->pdev->port->ieee1284; 405 pp->saved_state.mode = info->mode; 406 pp->saved_state.phase = info->phase; 407 info->mode = pp->state.mode; 408 info->phase = pp->state.phase; 409 pp->default_inactivity = parport_set_timeout(pp->pdev, 0); 410 parport_set_timeout(pp->pdev, pp->default_inactivity); 411 412 return 0; 413 } 414 case PPEXCL: 415 if (pp->pdev) { 416 dev_dbg(&pp->pdev->dev, 417 "too late for PPEXCL; already registered\n"); 418 if (pp->flags & PP_EXCL) 419 /* But it's not really an error. */ 420 return 0; 421 /* There's no chance of making the driver happy. */ 422 return -EINVAL; 423 } 424 425 /* Just remember to register the device exclusively 426 * when we finally do the registration. */ 427 pp->flags |= PP_EXCL; 428 return 0; 429 case PPSETMODE: 430 { 431 int mode; 432 433 if (copy_from_user(&mode, argp, sizeof(mode))) 434 return -EFAULT; 435 /* FIXME: validate mode */ 436 pp->state.mode = mode; 437 pp->state.phase = init_phase(mode); 438 439 if (pp->flags & PP_CLAIMED) { 440 pp->pdev->port->ieee1284.mode = mode; 441 pp->pdev->port->ieee1284.phase = pp->state.phase; 442 } 443 444 return 0; 445 } 446 case PPGETMODE: 447 { 448 int mode; 449 450 if (pp->flags & PP_CLAIMED) 451 mode = pp->pdev->port->ieee1284.mode; 452 else 453 mode = pp->state.mode; 454 455 if (copy_to_user(argp, &mode, sizeof(mode))) 456 return -EFAULT; 457 return 0; 458 } 459 case PPSETPHASE: 460 { 461 int phase; 462 463 if (copy_from_user(&phase, argp, sizeof(phase))) 464 return -EFAULT; 465 466 /* FIXME: validate phase */ 467 pp->state.phase = phase; 468 469 if (pp->flags & PP_CLAIMED) 470 pp->pdev->port->ieee1284.phase = phase; 471 472 return 0; 473 } 474 case PPGETPHASE: 475 { 476 int phase; 477 478 if (pp->flags & PP_CLAIMED) 479 phase = pp->pdev->port->ieee1284.phase; 480 else 481 phase = pp->state.phase; 482 if (copy_to_user(argp, &phase, sizeof(phase))) 483 return -EFAULT; 484 return 0; 485 } 486 case PPGETMODES: 487 { 488 unsigned int modes; 489 490 port = parport_find_number(minor); 491 if (!port) 492 return -ENODEV; 493 494 modes = port->modes; 495 parport_put_port(port); 496 if (copy_to_user(argp, &modes, sizeof(modes))) 497 return -EFAULT; 498 return 0; 499 } 500 case PPSETFLAGS: 501 { 502 int uflags; 503 504 if (copy_from_user(&uflags, argp, sizeof(uflags))) 505 return -EFAULT; 506 pp->flags &= ~PP_FLAGMASK; 507 pp->flags |= (uflags & PP_FLAGMASK); 508 return 0; 509 } 510 case PPGETFLAGS: 511 { 512 int uflags; 513 514 uflags = pp->flags & PP_FLAGMASK; 515 if (copy_to_user(argp, &uflags, sizeof(uflags))) 516 return -EFAULT; 517 return 0; 518 } 519 } /* end switch() */ 520 521 /* Everything else requires the port to be claimed, so check 522 * that now. */ 523 if ((pp->flags & PP_CLAIMED) == 0) { 524 pr_debug(CHRDEV "%x: claim the port first\n", minor); 525 return -EINVAL; 526 } 527 528 port = pp->pdev->port; 529 switch (cmd) { 530 case PPRSTATUS: 531 reg = parport_read_status(port); 532 if (copy_to_user(argp, ®, sizeof(reg))) 533 return -EFAULT; 534 return 0; 535 case PPRDATA: 536 reg = parport_read_data(port); 537 if (copy_to_user(argp, ®, sizeof(reg))) 538 return -EFAULT; 539 return 0; 540 case PPRCONTROL: 541 reg = parport_read_control(port); 542 if (copy_to_user(argp, ®, sizeof(reg))) 543 return -EFAULT; 544 return 0; 545 case PPYIELD: 546 parport_yield_blocking(pp->pdev); 547 return 0; 548 549 case PPRELEASE: 550 /* Save the state machine's state. */ 551 info = &pp->pdev->port->ieee1284; 552 pp->state.mode = info->mode; 553 pp->state.phase = info->phase; 554 info->mode = pp->saved_state.mode; 555 info->phase = pp->saved_state.phase; 556 parport_release(pp->pdev); 557 pp->flags &= ~PP_CLAIMED; 558 return 0; 559 560 case PPWCONTROL: 561 if (copy_from_user(®, argp, sizeof(reg))) 562 return -EFAULT; 563 parport_write_control(port, reg); 564 return 0; 565 566 case PPWDATA: 567 if (copy_from_user(®, argp, sizeof(reg))) 568 return -EFAULT; 569 parport_write_data(port, reg); 570 return 0; 571 572 case PPFCONTROL: 573 if (copy_from_user(&mask, argp, 574 sizeof(mask))) 575 return -EFAULT; 576 if (copy_from_user(®, 1 + (unsigned char __user *) arg, 577 sizeof(reg))) 578 return -EFAULT; 579 parport_frob_control(port, mask, reg); 580 return 0; 581 582 case PPDATADIR: 583 if (copy_from_user(&mode, argp, sizeof(mode))) 584 return -EFAULT; 585 if (mode) 586 port->ops->data_reverse(port); 587 else 588 port->ops->data_forward(port); 589 return 0; 590 591 case PPNEGOT: 592 if (copy_from_user(&mode, argp, sizeof(mode))) 593 return -EFAULT; 594 switch ((ret = parport_negotiate(port, mode))) { 595 case 0: break; 596 case -1: /* handshake failed, peripheral not IEEE 1284 */ 597 ret = -EIO; 598 break; 599 case 1: /* handshake succeeded, peripheral rejected mode */ 600 ret = -ENXIO; 601 break; 602 } 603 pp_enable_irq(pp); 604 return ret; 605 606 case PPWCTLONIRQ: 607 if (copy_from_user(®, argp, sizeof(reg))) 608 return -EFAULT; 609 610 /* Remember what to set the control lines to, for next 611 * time we get an interrupt. */ 612 pp->irqctl = reg; 613 pp->irqresponse = 1; 614 return 0; 615 616 case PPCLRIRQ: 617 ret = atomic_read(&pp->irqc); 618 if (copy_to_user(argp, &ret, sizeof(ret))) 619 return -EFAULT; 620 atomic_sub(ret, &pp->irqc); 621 return 0; 622 623 case PPSETTIME32: 624 if (copy_from_user(time32, argp, sizeof(time32))) 625 return -EFAULT; 626 627 if ((time32[0] < 0) || (time32[1] < 0)) 628 return -EINVAL; 629 630 return pp_set_timeout(pp->pdev, time32[0], time32[1]); 631 632 case PPSETTIME64: 633 if (copy_from_user(time64, argp, sizeof(time64))) 634 return -EFAULT; 635 636 if ((time64[0] < 0) || (time64[1] < 0)) 637 return -EINVAL; 638 639 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall()) 640 time64[1] >>= 32; 641 642 return pp_set_timeout(pp->pdev, time64[0], time64[1]); 643 644 case PPGETTIME32: 645 jiffies_to_timespec64(pp->pdev->timeout, &ts); 646 time32[0] = ts.tv_sec; 647 time32[1] = ts.tv_nsec / NSEC_PER_USEC; 648 649 if (copy_to_user(argp, time32, sizeof(time32))) 650 return -EFAULT; 651 652 return 0; 653 654 case PPGETTIME64: 655 jiffies_to_timespec64(pp->pdev->timeout, &ts); 656 time64[0] = ts.tv_sec; 657 time64[1] = ts.tv_nsec / NSEC_PER_USEC; 658 659 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall()) 660 time64[1] <<= 32; 661 662 if (copy_to_user(argp, time64, sizeof(time64))) 663 return -EFAULT; 664 665 return 0; 666 667 default: 668 dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd); 669 return -EINVAL; 670 } 671 672 /* Keep the compiler happy */ 673 return 0; 674 } 675 676 static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 677 { 678 long ret; 679 680 mutex_lock(&pp_do_mutex); 681 ret = pp_do_ioctl(file, cmd, arg); 682 mutex_unlock(&pp_do_mutex); 683 return ret; 684 } 685 686 static int pp_open(struct inode *inode, struct file *file) 687 { 688 unsigned int minor = iminor(inode); 689 struct pp_struct *pp; 690 691 if (minor >= PARPORT_MAX) 692 return -ENXIO; 693 694 pp = kmalloc_obj(struct pp_struct); 695 if (!pp) 696 return -ENOMEM; 697 698 pp->state.mode = IEEE1284_MODE_COMPAT; 699 pp->state.phase = init_phase(pp->state.mode); 700 pp->flags = 0; 701 pp->irqresponse = 0; 702 atomic_set(&pp->irqc, 0); 703 init_waitqueue_head(&pp->irq_wait); 704 705 /* Defer the actual device registration until the first claim. 706 * That way, we know whether or not the driver wants to have 707 * exclusive access to the port (PPEXCL). 708 */ 709 pp->pdev = NULL; 710 file->private_data = pp; 711 712 return 0; 713 } 714 715 static int pp_release(struct inode *inode, struct file *file) 716 { 717 unsigned int minor = iminor(inode); 718 struct pp_struct *pp = file->private_data; 719 int compat_negot; 720 721 compat_negot = 0; 722 if (!(pp->flags & PP_CLAIMED) && pp->pdev && 723 (pp->state.mode != IEEE1284_MODE_COMPAT)) { 724 struct ieee1284_info *info; 725 726 /* parport released, but not in compatibility mode */ 727 parport_claim_or_block(pp->pdev); 728 pp->flags |= PP_CLAIMED; 729 info = &pp->pdev->port->ieee1284; 730 pp->saved_state.mode = info->mode; 731 pp->saved_state.phase = info->phase; 732 info->mode = pp->state.mode; 733 info->phase = pp->state.phase; 734 compat_negot = 1; 735 } else if ((pp->flags & PP_CLAIMED) && pp->pdev && 736 (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) { 737 compat_negot = 2; 738 } 739 if (compat_negot) { 740 parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT); 741 dev_dbg(&pp->pdev->dev, 742 "negotiated back to compatibility mode because user-space forgot\n"); 743 } 744 745 if ((pp->flags & PP_CLAIMED) && pp->pdev) { 746 struct ieee1284_info *info; 747 748 info = &pp->pdev->port->ieee1284; 749 pp->state.mode = info->mode; 750 pp->state.phase = info->phase; 751 info->mode = pp->saved_state.mode; 752 info->phase = pp->saved_state.phase; 753 parport_release(pp->pdev); 754 if (compat_negot != 1) { 755 pr_debug(CHRDEV "%x: released pardevice " 756 "because user-space forgot\n", minor); 757 } 758 } 759 760 if (pp->pdev) { 761 parport_unregister_device(pp->pdev); 762 ida_free(&ida_index, pp->index); 763 pp->pdev = NULL; 764 pr_debug(CHRDEV "%x: unregistered pardevice\n", minor); 765 } 766 767 kfree(pp); 768 769 return 0; 770 } 771 772 /* No kernel lock held - fine */ 773 static __poll_t pp_poll(struct file *file, poll_table *wait) 774 { 775 struct pp_struct *pp = file->private_data; 776 __poll_t mask = 0; 777 778 poll_wait(file, &pp->irq_wait, wait); 779 if (atomic_read(&pp->irqc)) 780 mask |= EPOLLIN | EPOLLRDNORM; 781 782 return mask; 783 } 784 785 static const struct class ppdev_class = { 786 .name = CHRDEV, 787 }; 788 789 static const struct file_operations pp_fops = { 790 .owner = THIS_MODULE, 791 .read = pp_read, 792 .write = pp_write, 793 .poll = pp_poll, 794 .unlocked_ioctl = pp_ioctl, 795 .compat_ioctl = compat_ptr_ioctl, 796 .open = pp_open, 797 .release = pp_release, 798 }; 799 800 static void pp_attach(struct parport *port) 801 { 802 struct device *ret; 803 804 if (devices[port->number]) 805 return; 806 807 ret = device_create(&ppdev_class, port->dev, 808 MKDEV(PP_MAJOR, port->number), NULL, 809 "parport%d", port->number); 810 if (IS_ERR(ret)) { 811 pr_err("Failed to create device parport%d\n", 812 port->number); 813 return; 814 } 815 devices[port->number] = ret; 816 } 817 818 static void pp_detach(struct parport *port) 819 { 820 if (!devices[port->number]) 821 return; 822 823 device_destroy(&ppdev_class, MKDEV(PP_MAJOR, port->number)); 824 devices[port->number] = NULL; 825 } 826 827 static int pp_probe(struct pardevice *par_dev) 828 { 829 struct device_driver *drv = par_dev->dev.driver; 830 int len = strlen(drv->name); 831 832 if (strncmp(par_dev->name, drv->name, len)) 833 return -ENODEV; 834 835 return 0; 836 } 837 838 static struct parport_driver pp_driver = { 839 .name = CHRDEV, 840 .probe = pp_probe, 841 .match_port = pp_attach, 842 .detach = pp_detach, 843 }; 844 845 static int __init ppdev_init(void) 846 { 847 int err = 0; 848 849 if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) { 850 pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR); 851 return -EIO; 852 } 853 err = class_register(&ppdev_class); 854 if (err) 855 goto out_chrdev; 856 857 err = parport_register_driver(&pp_driver); 858 if (err < 0) { 859 pr_warn(CHRDEV ": unable to register with parport\n"); 860 goto out_class; 861 } 862 863 pr_info(PP_VERSION "\n"); 864 goto out; 865 866 out_class: 867 class_unregister(&ppdev_class); 868 out_chrdev: 869 unregister_chrdev(PP_MAJOR, CHRDEV); 870 out: 871 return err; 872 } 873 874 static void __exit ppdev_cleanup(void) 875 { 876 /* Clean up all parport stuff */ 877 parport_unregister_driver(&pp_driver); 878 class_unregister(&ppdev_class); 879 unregister_chrdev(PP_MAJOR, CHRDEV); 880 } 881 882 module_init(ppdev_init); 883 module_exit(ppdev_cleanup); 884 885 MODULE_DESCRIPTION("Support for user-space parallel port device drivers"); 886 MODULE_LICENSE("GPL"); 887 MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR); 888