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; 300 } 301 302 index = ida_simple_get(&ida_index, 0, 0, GFP_KERNEL); 303 memset(&ppdev_cb, 0, sizeof(ppdev_cb)); 304 ppdev_cb.irq_func = pp_irq; 305 ppdev_cb.flags = (pp->flags & PP_EXCL) ? PARPORT_FLAG_EXCL : 0; 306 ppdev_cb.private = pp; 307 pdev = parport_register_dev_model(port, name, &ppdev_cb, index); 308 parport_put_port(port); 309 310 if (!pdev) { 311 pr_warn("%s: failed to register device!\n", name); 312 rc = -ENXIO; 313 ida_simple_remove(&ida_index, index); 314 goto err; 315 } 316 317 pp->pdev = pdev; 318 pp->index = index; 319 dev_dbg(&pdev->dev, "registered pardevice\n"); 320 err: 321 kfree(name); 322 return rc; 323 } 324 325 static enum ieee1284_phase init_phase(int mode) 326 { 327 switch (mode & ~(IEEE1284_DEVICEID 328 | IEEE1284_ADDR)) { 329 case IEEE1284_MODE_NIBBLE: 330 case IEEE1284_MODE_BYTE: 331 return IEEE1284_PH_REV_IDLE; 332 } 333 return IEEE1284_PH_FWD_IDLE; 334 } 335 336 static int pp_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec) 337 { 338 long to_jiffies; 339 340 if ((tv_sec < 0) || (tv_usec < 0)) 341 return -EINVAL; 342 343 to_jiffies = usecs_to_jiffies(tv_usec); 344 to_jiffies += tv_sec * HZ; 345 if (to_jiffies <= 0) 346 return -EINVAL; 347 348 pdev->timeout = to_jiffies; 349 return 0; 350 } 351 352 static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 353 { 354 unsigned int minor = iminor(file_inode(file)); 355 struct pp_struct *pp = file->private_data; 356 struct parport *port; 357 void __user *argp = (void __user *)arg; 358 359 /* First handle the cases that don't take arguments. */ 360 switch (cmd) { 361 case PPCLAIM: 362 { 363 struct ieee1284_info *info; 364 int ret; 365 366 if (pp->flags & PP_CLAIMED) { 367 dev_dbg(&pp->pdev->dev, "you've already got it!\n"); 368 return -EINVAL; 369 } 370 371 /* Deferred device registration. */ 372 if (!pp->pdev) { 373 int err = register_device(minor, pp); 374 375 if (err) 376 return err; 377 } 378 379 ret = parport_claim_or_block(pp->pdev); 380 if (ret < 0) 381 return ret; 382 383 pp->flags |= PP_CLAIMED; 384 385 /* For interrupt-reporting to work, we need to be 386 * informed of each interrupt. */ 387 pp_enable_irq(pp); 388 389 /* We may need to fix up the state machine. */ 390 info = &pp->pdev->port->ieee1284; 391 pp->saved_state.mode = info->mode; 392 pp->saved_state.phase = info->phase; 393 info->mode = pp->state.mode; 394 info->phase = pp->state.phase; 395 pp->default_inactivity = parport_set_timeout(pp->pdev, 0); 396 parport_set_timeout(pp->pdev, pp->default_inactivity); 397 398 return 0; 399 } 400 case PPEXCL: 401 if (pp->pdev) { 402 dev_dbg(&pp->pdev->dev, 403 "too late for PPEXCL; already registered\n"); 404 if (pp->flags & PP_EXCL) 405 /* But it's not really an error. */ 406 return 0; 407 /* There's no chance of making the driver happy. */ 408 return -EINVAL; 409 } 410 411 /* Just remember to register the device exclusively 412 * when we finally do the registration. */ 413 pp->flags |= PP_EXCL; 414 return 0; 415 case PPSETMODE: 416 { 417 int mode; 418 419 if (copy_from_user(&mode, argp, sizeof(mode))) 420 return -EFAULT; 421 /* FIXME: validate mode */ 422 pp->state.mode = mode; 423 pp->state.phase = init_phase(mode); 424 425 if (pp->flags & PP_CLAIMED) { 426 pp->pdev->port->ieee1284.mode = mode; 427 pp->pdev->port->ieee1284.phase = pp->state.phase; 428 } 429 430 return 0; 431 } 432 case PPGETMODE: 433 { 434 int mode; 435 436 if (pp->flags & PP_CLAIMED) 437 mode = pp->pdev->port->ieee1284.mode; 438 else 439 mode = pp->state.mode; 440 441 if (copy_to_user(argp, &mode, sizeof(mode))) 442 return -EFAULT; 443 return 0; 444 } 445 case PPSETPHASE: 446 { 447 int phase; 448 449 if (copy_from_user(&phase, argp, sizeof(phase))) 450 return -EFAULT; 451 452 /* FIXME: validate phase */ 453 pp->state.phase = phase; 454 455 if (pp->flags & PP_CLAIMED) 456 pp->pdev->port->ieee1284.phase = phase; 457 458 return 0; 459 } 460 case PPGETPHASE: 461 { 462 int phase; 463 464 if (pp->flags & PP_CLAIMED) 465 phase = pp->pdev->port->ieee1284.phase; 466 else 467 phase = pp->state.phase; 468 if (copy_to_user(argp, &phase, sizeof(phase))) 469 return -EFAULT; 470 return 0; 471 } 472 case PPGETMODES: 473 { 474 unsigned int modes; 475 476 port = parport_find_number(minor); 477 if (!port) 478 return -ENODEV; 479 480 modes = port->modes; 481 parport_put_port(port); 482 if (copy_to_user(argp, &modes, sizeof(modes))) 483 return -EFAULT; 484 return 0; 485 } 486 case PPSETFLAGS: 487 { 488 int uflags; 489 490 if (copy_from_user(&uflags, argp, sizeof(uflags))) 491 return -EFAULT; 492 pp->flags &= ~PP_FLAGMASK; 493 pp->flags |= (uflags & PP_FLAGMASK); 494 return 0; 495 } 496 case PPGETFLAGS: 497 { 498 int uflags; 499 500 uflags = pp->flags & PP_FLAGMASK; 501 if (copy_to_user(argp, &uflags, sizeof(uflags))) 502 return -EFAULT; 503 return 0; 504 } 505 } /* end switch() */ 506 507 /* Everything else requires the port to be claimed, so check 508 * that now. */ 509 if ((pp->flags & PP_CLAIMED) == 0) { 510 pr_debug(CHRDEV "%x: claim the port first\n", minor); 511 return -EINVAL; 512 } 513 514 port = pp->pdev->port; 515 switch (cmd) { 516 struct ieee1284_info *info; 517 unsigned char reg; 518 unsigned char mask; 519 int mode; 520 s32 time32[2]; 521 s64 time64[2]; 522 struct timespec64 ts; 523 int ret; 524 525 case PPRSTATUS: 526 reg = parport_read_status(port); 527 if (copy_to_user(argp, ®, sizeof(reg))) 528 return -EFAULT; 529 return 0; 530 case PPRDATA: 531 reg = parport_read_data(port); 532 if (copy_to_user(argp, ®, sizeof(reg))) 533 return -EFAULT; 534 return 0; 535 case PPRCONTROL: 536 reg = parport_read_control(port); 537 if (copy_to_user(argp, ®, sizeof(reg))) 538 return -EFAULT; 539 return 0; 540 case PPYIELD: 541 parport_yield_blocking(pp->pdev); 542 return 0; 543 544 case PPRELEASE: 545 /* Save the state machine's state. */ 546 info = &pp->pdev->port->ieee1284; 547 pp->state.mode = info->mode; 548 pp->state.phase = info->phase; 549 info->mode = pp->saved_state.mode; 550 info->phase = pp->saved_state.phase; 551 parport_release(pp->pdev); 552 pp->flags &= ~PP_CLAIMED; 553 return 0; 554 555 case PPWCONTROL: 556 if (copy_from_user(®, argp, sizeof(reg))) 557 return -EFAULT; 558 parport_write_control(port, reg); 559 return 0; 560 561 case PPWDATA: 562 if (copy_from_user(®, argp, sizeof(reg))) 563 return -EFAULT; 564 parport_write_data(port, reg); 565 return 0; 566 567 case PPFCONTROL: 568 if (copy_from_user(&mask, argp, 569 sizeof(mask))) 570 return -EFAULT; 571 if (copy_from_user(®, 1 + (unsigned char __user *) arg, 572 sizeof(reg))) 573 return -EFAULT; 574 parport_frob_control(port, mask, reg); 575 return 0; 576 577 case PPDATADIR: 578 if (copy_from_user(&mode, argp, sizeof(mode))) 579 return -EFAULT; 580 if (mode) 581 port->ops->data_reverse(port); 582 else 583 port->ops->data_forward(port); 584 return 0; 585 586 case PPNEGOT: 587 if (copy_from_user(&mode, argp, sizeof(mode))) 588 return -EFAULT; 589 switch ((ret = parport_negotiate(port, mode))) { 590 case 0: break; 591 case -1: /* handshake failed, peripheral not IEEE 1284 */ 592 ret = -EIO; 593 break; 594 case 1: /* handshake succeeded, peripheral rejected mode */ 595 ret = -ENXIO; 596 break; 597 } 598 pp_enable_irq(pp); 599 return ret; 600 601 case PPWCTLONIRQ: 602 if (copy_from_user(®, argp, sizeof(reg))) 603 return -EFAULT; 604 605 /* Remember what to set the control lines to, for next 606 * time we get an interrupt. */ 607 pp->irqctl = reg; 608 pp->irqresponse = 1; 609 return 0; 610 611 case PPCLRIRQ: 612 ret = atomic_read(&pp->irqc); 613 if (copy_to_user(argp, &ret, sizeof(ret))) 614 return -EFAULT; 615 atomic_sub(ret, &pp->irqc); 616 return 0; 617 618 case PPSETTIME32: 619 if (copy_from_user(time32, argp, sizeof(time32))) 620 return -EFAULT; 621 622 return pp_set_timeout(pp->pdev, time32[0], time32[1]); 623 624 case PPSETTIME64: 625 if (copy_from_user(time64, argp, sizeof(time64))) 626 return -EFAULT; 627 628 return pp_set_timeout(pp->pdev, time64[0], time64[1]); 629 630 case PPGETTIME32: 631 jiffies_to_timespec64(pp->pdev->timeout, &ts); 632 time32[0] = ts.tv_sec; 633 time32[1] = ts.tv_nsec / NSEC_PER_USEC; 634 if ((time32[0] < 0) || (time32[1] < 0)) 635 return -EINVAL; 636 637 if (copy_to_user(argp, time32, sizeof(time32))) 638 return -EFAULT; 639 640 return 0; 641 642 case PPGETTIME64: 643 jiffies_to_timespec64(pp->pdev->timeout, &ts); 644 time64[0] = ts.tv_sec; 645 time64[1] = ts.tv_nsec / NSEC_PER_USEC; 646 if ((time64[0] < 0) || (time64[1] < 0)) 647 return -EINVAL; 648 649 if (copy_to_user(argp, time64, sizeof(time64))) 650 return -EFAULT; 651 652 return 0; 653 654 default: 655 dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd); 656 return -EINVAL; 657 } 658 659 /* Keep the compiler happy */ 660 return 0; 661 } 662 663 static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 664 { 665 long ret; 666 667 mutex_lock(&pp_do_mutex); 668 ret = pp_do_ioctl(file, cmd, arg); 669 mutex_unlock(&pp_do_mutex); 670 return ret; 671 } 672 673 #ifdef CONFIG_COMPAT 674 static long pp_compat_ioctl(struct file *file, unsigned int cmd, 675 unsigned long arg) 676 { 677 return pp_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); 678 } 679 #endif 680 681 static int pp_open(struct inode *inode, struct file *file) 682 { 683 unsigned int minor = iminor(inode); 684 struct pp_struct *pp; 685 686 if (minor >= PARPORT_MAX) 687 return -ENXIO; 688 689 pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL); 690 if (!pp) 691 return -ENOMEM; 692 693 pp->state.mode = IEEE1284_MODE_COMPAT; 694 pp->state.phase = init_phase(pp->state.mode); 695 pp->flags = 0; 696 pp->irqresponse = 0; 697 atomic_set(&pp->irqc, 0); 698 init_waitqueue_head(&pp->irq_wait); 699 700 /* Defer the actual device registration until the first claim. 701 * That way, we know whether or not the driver wants to have 702 * exclusive access to the port (PPEXCL). 703 */ 704 pp->pdev = NULL; 705 file->private_data = pp; 706 707 return 0; 708 } 709 710 static int pp_release(struct inode *inode, struct file *file) 711 { 712 unsigned int minor = iminor(inode); 713 struct pp_struct *pp = file->private_data; 714 int compat_negot; 715 716 compat_negot = 0; 717 if (!(pp->flags & PP_CLAIMED) && pp->pdev && 718 (pp->state.mode != IEEE1284_MODE_COMPAT)) { 719 struct ieee1284_info *info; 720 721 /* parport released, but not in compatibility mode */ 722 parport_claim_or_block(pp->pdev); 723 pp->flags |= PP_CLAIMED; 724 info = &pp->pdev->port->ieee1284; 725 pp->saved_state.mode = info->mode; 726 pp->saved_state.phase = info->phase; 727 info->mode = pp->state.mode; 728 info->phase = pp->state.phase; 729 compat_negot = 1; 730 } else if ((pp->flags & PP_CLAIMED) && pp->pdev && 731 (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) { 732 compat_negot = 2; 733 } 734 if (compat_negot) { 735 parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT); 736 dev_dbg(&pp->pdev->dev, 737 "negotiated back to compatibility mode because user-space forgot\n"); 738 } 739 740 if (pp->flags & PP_CLAIMED) { 741 struct ieee1284_info *info; 742 743 info = &pp->pdev->port->ieee1284; 744 pp->state.mode = info->mode; 745 pp->state.phase = info->phase; 746 info->mode = pp->saved_state.mode; 747 info->phase = pp->saved_state.phase; 748 parport_release(pp->pdev); 749 if (compat_negot != 1) { 750 pr_debug(CHRDEV "%x: released pardevice " 751 "because user-space forgot\n", minor); 752 } 753 } 754 755 if (pp->pdev) { 756 parport_unregister_device(pp->pdev); 757 ida_simple_remove(&ida_index, pp->index); 758 pp->pdev = NULL; 759 pr_debug(CHRDEV "%x: unregistered pardevice\n", minor); 760 } 761 762 kfree(pp); 763 764 return 0; 765 } 766 767 /* No kernel lock held - fine */ 768 static __poll_t pp_poll(struct file *file, poll_table *wait) 769 { 770 struct pp_struct *pp = file->private_data; 771 __poll_t mask = 0; 772 773 poll_wait(file, &pp->irq_wait, wait); 774 if (atomic_read(&pp->irqc)) 775 mask |= EPOLLIN | EPOLLRDNORM; 776 777 return mask; 778 } 779 780 static struct class *ppdev_class; 781 782 static const struct file_operations pp_fops = { 783 .owner = THIS_MODULE, 784 .llseek = no_llseek, 785 .read = pp_read, 786 .write = pp_write, 787 .poll = pp_poll, 788 .unlocked_ioctl = pp_ioctl, 789 #ifdef CONFIG_COMPAT 790 .compat_ioctl = pp_compat_ioctl, 791 #endif 792 .open = pp_open, 793 .release = pp_release, 794 }; 795 796 static void pp_attach(struct parport *port) 797 { 798 struct device *ret; 799 800 if (devices[port->number]) 801 return; 802 803 ret = device_create(ppdev_class, port->dev, 804 MKDEV(PP_MAJOR, port->number), NULL, 805 "parport%d", port->number); 806 if (IS_ERR(ret)) { 807 pr_err("Failed to create device parport%d\n", 808 port->number); 809 return; 810 } 811 devices[port->number] = ret; 812 } 813 814 static void pp_detach(struct parport *port) 815 { 816 if (!devices[port->number]) 817 return; 818 819 device_destroy(ppdev_class, MKDEV(PP_MAJOR, port->number)); 820 devices[port->number] = NULL; 821 } 822 823 static int pp_probe(struct pardevice *par_dev) 824 { 825 struct device_driver *drv = par_dev->dev.driver; 826 int len = strlen(drv->name); 827 828 if (strncmp(par_dev->name, drv->name, len)) 829 return -ENODEV; 830 831 return 0; 832 } 833 834 static struct parport_driver pp_driver = { 835 .name = CHRDEV, 836 .probe = pp_probe, 837 .match_port = pp_attach, 838 .detach = pp_detach, 839 .devmodel = true, 840 }; 841 842 static int __init ppdev_init(void) 843 { 844 int err = 0; 845 846 if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) { 847 pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR); 848 return -EIO; 849 } 850 ppdev_class = class_create(THIS_MODULE, CHRDEV); 851 if (IS_ERR(ppdev_class)) { 852 err = PTR_ERR(ppdev_class); 853 goto out_chrdev; 854 } 855 err = parport_register_driver(&pp_driver); 856 if (err < 0) { 857 pr_warn(CHRDEV ": unable to register with parport\n"); 858 goto out_class; 859 } 860 861 pr_info(PP_VERSION "\n"); 862 goto out; 863 864 out_class: 865 class_destroy(ppdev_class); 866 out_chrdev: 867 unregister_chrdev(PP_MAJOR, CHRDEV); 868 out: 869 return err; 870 } 871 872 static void __exit ppdev_cleanup(void) 873 { 874 /* Clean up all parport stuff */ 875 parport_unregister_driver(&pp_driver); 876 class_destroy(ppdev_class); 877 unregister_chrdev(PP_MAJOR, CHRDEV); 878 } 879 880 module_init(ppdev_init); 881 module_exit(ppdev_cleanup); 882 883 MODULE_LICENSE("GPL"); 884 MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR); 885