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 pp_enable_irq(struct pp_struct * pp)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 pp_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)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 pp_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)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 pp_irq(void * private)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 register_device(int minor,struct pp_struct * pp)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 init_phase(int mode)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 pp_set_timeout(struct pardevice * pdev,long tv_sec,int tv_usec)343 static int pp_set_timeout(struct pardevice *pdev, long tv_sec, int tv_usec) 344 { 345 long to_jiffies; 346 347 if ((tv_sec < 0) || (tv_usec < 0)) 348 return -EINVAL; 349 350 to_jiffies = usecs_to_jiffies(tv_usec); 351 to_jiffies += tv_sec * HZ; 352 if (to_jiffies <= 0) 353 return -EINVAL; 354 355 pdev->timeout = to_jiffies; 356 return 0; 357 } 358 pp_do_ioctl(struct file * file,unsigned int cmd,unsigned long arg)359 static int pp_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 360 { 361 unsigned int minor = iminor(file_inode(file)); 362 struct pp_struct *pp = file->private_data; 363 struct parport *port; 364 void __user *argp = (void __user *)arg; 365 struct ieee1284_info *info; 366 unsigned char reg; 367 unsigned char mask; 368 int mode; 369 s32 time32[2]; 370 s64 time64[2]; 371 struct timespec64 ts; 372 int ret; 373 374 /* First handle the cases that don't take arguments. */ 375 switch (cmd) { 376 case PPCLAIM: 377 { 378 if (pp->flags & PP_CLAIMED) { 379 dev_dbg(&pp->pdev->dev, "you've already got it!\n"); 380 return -EINVAL; 381 } 382 383 /* Deferred device registration. */ 384 if (!pp->pdev) { 385 int err = register_device(minor, pp); 386 387 if (err) 388 return err; 389 } 390 391 ret = parport_claim_or_block(pp->pdev); 392 if (ret < 0) 393 return ret; 394 395 pp->flags |= PP_CLAIMED; 396 397 /* For interrupt-reporting to work, we need to be 398 * informed of each interrupt. */ 399 pp_enable_irq(pp); 400 401 /* We may need to fix up the state machine. */ 402 info = &pp->pdev->port->ieee1284; 403 pp->saved_state.mode = info->mode; 404 pp->saved_state.phase = info->phase; 405 info->mode = pp->state.mode; 406 info->phase = pp->state.phase; 407 pp->default_inactivity = parport_set_timeout(pp->pdev, 0); 408 parport_set_timeout(pp->pdev, pp->default_inactivity); 409 410 return 0; 411 } 412 case PPEXCL: 413 if (pp->pdev) { 414 dev_dbg(&pp->pdev->dev, 415 "too late for PPEXCL; already registered\n"); 416 if (pp->flags & PP_EXCL) 417 /* But it's not really an error. */ 418 return 0; 419 /* There's no chance of making the driver happy. */ 420 return -EINVAL; 421 } 422 423 /* Just remember to register the device exclusively 424 * when we finally do the registration. */ 425 pp->flags |= PP_EXCL; 426 return 0; 427 case PPSETMODE: 428 { 429 int mode; 430 431 if (copy_from_user(&mode, argp, sizeof(mode))) 432 return -EFAULT; 433 /* FIXME: validate mode */ 434 pp->state.mode = mode; 435 pp->state.phase = init_phase(mode); 436 437 if (pp->flags & PP_CLAIMED) { 438 pp->pdev->port->ieee1284.mode = mode; 439 pp->pdev->port->ieee1284.phase = pp->state.phase; 440 } 441 442 return 0; 443 } 444 case PPGETMODE: 445 { 446 int mode; 447 448 if (pp->flags & PP_CLAIMED) 449 mode = pp->pdev->port->ieee1284.mode; 450 else 451 mode = pp->state.mode; 452 453 if (copy_to_user(argp, &mode, sizeof(mode))) 454 return -EFAULT; 455 return 0; 456 } 457 case PPSETPHASE: 458 { 459 int phase; 460 461 if (copy_from_user(&phase, argp, sizeof(phase))) 462 return -EFAULT; 463 464 /* FIXME: validate phase */ 465 pp->state.phase = phase; 466 467 if (pp->flags & PP_CLAIMED) 468 pp->pdev->port->ieee1284.phase = phase; 469 470 return 0; 471 } 472 case PPGETPHASE: 473 { 474 int phase; 475 476 if (pp->flags & PP_CLAIMED) 477 phase = pp->pdev->port->ieee1284.phase; 478 else 479 phase = pp->state.phase; 480 if (copy_to_user(argp, &phase, sizeof(phase))) 481 return -EFAULT; 482 return 0; 483 } 484 case PPGETMODES: 485 { 486 unsigned int modes; 487 488 port = parport_find_number(minor); 489 if (!port) 490 return -ENODEV; 491 492 modes = port->modes; 493 parport_put_port(port); 494 if (copy_to_user(argp, &modes, sizeof(modes))) 495 return -EFAULT; 496 return 0; 497 } 498 case PPSETFLAGS: 499 { 500 int uflags; 501 502 if (copy_from_user(&uflags, argp, sizeof(uflags))) 503 return -EFAULT; 504 pp->flags &= ~PP_FLAGMASK; 505 pp->flags |= (uflags & PP_FLAGMASK); 506 return 0; 507 } 508 case PPGETFLAGS: 509 { 510 int uflags; 511 512 uflags = pp->flags & PP_FLAGMASK; 513 if (copy_to_user(argp, &uflags, sizeof(uflags))) 514 return -EFAULT; 515 return 0; 516 } 517 } /* end switch() */ 518 519 /* Everything else requires the port to be claimed, so check 520 * that now. */ 521 if ((pp->flags & PP_CLAIMED) == 0) { 522 pr_debug(CHRDEV "%x: claim the port first\n", minor); 523 return -EINVAL; 524 } 525 526 port = pp->pdev->port; 527 switch (cmd) { 528 case PPRSTATUS: 529 reg = parport_read_status(port); 530 if (copy_to_user(argp, ®, sizeof(reg))) 531 return -EFAULT; 532 return 0; 533 case PPRDATA: 534 reg = parport_read_data(port); 535 if (copy_to_user(argp, ®, sizeof(reg))) 536 return -EFAULT; 537 return 0; 538 case PPRCONTROL: 539 reg = parport_read_control(port); 540 if (copy_to_user(argp, ®, sizeof(reg))) 541 return -EFAULT; 542 return 0; 543 case PPYIELD: 544 parport_yield_blocking(pp->pdev); 545 return 0; 546 547 case PPRELEASE: 548 /* Save the state machine's state. */ 549 info = &pp->pdev->port->ieee1284; 550 pp->state.mode = info->mode; 551 pp->state.phase = info->phase; 552 info->mode = pp->saved_state.mode; 553 info->phase = pp->saved_state.phase; 554 parport_release(pp->pdev); 555 pp->flags &= ~PP_CLAIMED; 556 return 0; 557 558 case PPWCONTROL: 559 if (copy_from_user(®, argp, sizeof(reg))) 560 return -EFAULT; 561 parport_write_control(port, reg); 562 return 0; 563 564 case PPWDATA: 565 if (copy_from_user(®, argp, sizeof(reg))) 566 return -EFAULT; 567 parport_write_data(port, reg); 568 return 0; 569 570 case PPFCONTROL: 571 if (copy_from_user(&mask, argp, 572 sizeof(mask))) 573 return -EFAULT; 574 if (copy_from_user(®, 1 + (unsigned char __user *) arg, 575 sizeof(reg))) 576 return -EFAULT; 577 parport_frob_control(port, mask, reg); 578 return 0; 579 580 case PPDATADIR: 581 if (copy_from_user(&mode, argp, sizeof(mode))) 582 return -EFAULT; 583 if (mode) 584 port->ops->data_reverse(port); 585 else 586 port->ops->data_forward(port); 587 return 0; 588 589 case PPNEGOT: 590 if (copy_from_user(&mode, argp, sizeof(mode))) 591 return -EFAULT; 592 switch ((ret = parport_negotiate(port, mode))) { 593 case 0: break; 594 case -1: /* handshake failed, peripheral not IEEE 1284 */ 595 ret = -EIO; 596 break; 597 case 1: /* handshake succeeded, peripheral rejected mode */ 598 ret = -ENXIO; 599 break; 600 } 601 pp_enable_irq(pp); 602 return ret; 603 604 case PPWCTLONIRQ: 605 if (copy_from_user(®, argp, sizeof(reg))) 606 return -EFAULT; 607 608 /* Remember what to set the control lines to, for next 609 * time we get an interrupt. */ 610 pp->irqctl = reg; 611 pp->irqresponse = 1; 612 return 0; 613 614 case PPCLRIRQ: 615 ret = atomic_read(&pp->irqc); 616 if (copy_to_user(argp, &ret, sizeof(ret))) 617 return -EFAULT; 618 atomic_sub(ret, &pp->irqc); 619 return 0; 620 621 case PPSETTIME32: 622 if (copy_from_user(time32, argp, sizeof(time32))) 623 return -EFAULT; 624 625 if ((time32[0] < 0) || (time32[1] < 0)) 626 return -EINVAL; 627 628 return pp_set_timeout(pp->pdev, time32[0], time32[1]); 629 630 case PPSETTIME64: 631 if (copy_from_user(time64, argp, sizeof(time64))) 632 return -EFAULT; 633 634 if ((time64[0] < 0) || (time64[1] < 0)) 635 return -EINVAL; 636 637 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall()) 638 time64[1] >>= 32; 639 640 return pp_set_timeout(pp->pdev, time64[0], time64[1]); 641 642 case PPGETTIME32: 643 jiffies_to_timespec64(pp->pdev->timeout, &ts); 644 time32[0] = ts.tv_sec; 645 time32[1] = ts.tv_nsec / NSEC_PER_USEC; 646 647 if (copy_to_user(argp, time32, sizeof(time32))) 648 return -EFAULT; 649 650 return 0; 651 652 case PPGETTIME64: 653 jiffies_to_timespec64(pp->pdev->timeout, &ts); 654 time64[0] = ts.tv_sec; 655 time64[1] = ts.tv_nsec / NSEC_PER_USEC; 656 657 if (IS_ENABLED(CONFIG_SPARC64) && !in_compat_syscall()) 658 time64[1] <<= 32; 659 660 if (copy_to_user(argp, time64, sizeof(time64))) 661 return -EFAULT; 662 663 return 0; 664 665 default: 666 dev_dbg(&pp->pdev->dev, "What? (cmd=0x%x)\n", cmd); 667 return -EINVAL; 668 } 669 670 /* Keep the compiler happy */ 671 return 0; 672 } 673 pp_ioctl(struct file * file,unsigned int cmd,unsigned long arg)674 static long pp_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 675 { 676 long ret; 677 678 mutex_lock(&pp_do_mutex); 679 ret = pp_do_ioctl(file, cmd, arg); 680 mutex_unlock(&pp_do_mutex); 681 return ret; 682 } 683 pp_open(struct inode * inode,struct file * file)684 static int pp_open(struct inode *inode, struct file *file) 685 { 686 unsigned int minor = iminor(inode); 687 struct pp_struct *pp; 688 689 if (minor >= PARPORT_MAX) 690 return -ENXIO; 691 692 pp = kmalloc(sizeof(struct pp_struct), GFP_KERNEL); 693 if (!pp) 694 return -ENOMEM; 695 696 pp->state.mode = IEEE1284_MODE_COMPAT; 697 pp->state.phase = init_phase(pp->state.mode); 698 pp->flags = 0; 699 pp->irqresponse = 0; 700 atomic_set(&pp->irqc, 0); 701 init_waitqueue_head(&pp->irq_wait); 702 703 /* Defer the actual device registration until the first claim. 704 * That way, we know whether or not the driver wants to have 705 * exclusive access to the port (PPEXCL). 706 */ 707 pp->pdev = NULL; 708 file->private_data = pp; 709 710 return 0; 711 } 712 pp_release(struct inode * inode,struct file * file)713 static int pp_release(struct inode *inode, struct file *file) 714 { 715 unsigned int minor = iminor(inode); 716 struct pp_struct *pp = file->private_data; 717 int compat_negot; 718 719 compat_negot = 0; 720 if (!(pp->flags & PP_CLAIMED) && pp->pdev && 721 (pp->state.mode != IEEE1284_MODE_COMPAT)) { 722 struct ieee1284_info *info; 723 724 /* parport released, but not in compatibility mode */ 725 parport_claim_or_block(pp->pdev); 726 pp->flags |= PP_CLAIMED; 727 info = &pp->pdev->port->ieee1284; 728 pp->saved_state.mode = info->mode; 729 pp->saved_state.phase = info->phase; 730 info->mode = pp->state.mode; 731 info->phase = pp->state.phase; 732 compat_negot = 1; 733 } else if ((pp->flags & PP_CLAIMED) && pp->pdev && 734 (pp->pdev->port->ieee1284.mode != IEEE1284_MODE_COMPAT)) { 735 compat_negot = 2; 736 } 737 if (compat_negot) { 738 parport_negotiate(pp->pdev->port, IEEE1284_MODE_COMPAT); 739 dev_dbg(&pp->pdev->dev, 740 "negotiated back to compatibility mode because user-space forgot\n"); 741 } 742 743 if ((pp->flags & PP_CLAIMED) && pp->pdev) { 744 struct ieee1284_info *info; 745 746 info = &pp->pdev->port->ieee1284; 747 pp->state.mode = info->mode; 748 pp->state.phase = info->phase; 749 info->mode = pp->saved_state.mode; 750 info->phase = pp->saved_state.phase; 751 parport_release(pp->pdev); 752 if (compat_negot != 1) { 753 pr_debug(CHRDEV "%x: released pardevice " 754 "because user-space forgot\n", minor); 755 } 756 } 757 758 if (pp->pdev) { 759 parport_unregister_device(pp->pdev); 760 ida_free(&ida_index, pp->index); 761 pp->pdev = NULL; 762 pr_debug(CHRDEV "%x: unregistered pardevice\n", minor); 763 } 764 765 kfree(pp); 766 767 return 0; 768 } 769 770 /* No kernel lock held - fine */ pp_poll(struct file * file,poll_table * wait)771 static __poll_t pp_poll(struct file *file, poll_table *wait) 772 { 773 struct pp_struct *pp = file->private_data; 774 __poll_t mask = 0; 775 776 poll_wait(file, &pp->irq_wait, wait); 777 if (atomic_read(&pp->irqc)) 778 mask |= EPOLLIN | EPOLLRDNORM; 779 780 return mask; 781 } 782 783 static const struct class ppdev_class = { 784 .name = CHRDEV, 785 }; 786 787 static const struct file_operations pp_fops = { 788 .owner = THIS_MODULE, 789 .read = pp_read, 790 .write = pp_write, 791 .poll = pp_poll, 792 .unlocked_ioctl = pp_ioctl, 793 .compat_ioctl = compat_ptr_ioctl, 794 .open = pp_open, 795 .release = pp_release, 796 }; 797 pp_attach(struct parport * port)798 static void pp_attach(struct parport *port) 799 { 800 struct device *ret; 801 802 if (devices[port->number]) 803 return; 804 805 ret = device_create(&ppdev_class, port->dev, 806 MKDEV(PP_MAJOR, port->number), NULL, 807 "parport%d", port->number); 808 if (IS_ERR(ret)) { 809 pr_err("Failed to create device parport%d\n", 810 port->number); 811 return; 812 } 813 devices[port->number] = ret; 814 } 815 pp_detach(struct parport * port)816 static void pp_detach(struct parport *port) 817 { 818 if (!devices[port->number]) 819 return; 820 821 device_destroy(&ppdev_class, MKDEV(PP_MAJOR, port->number)); 822 devices[port->number] = NULL; 823 } 824 pp_probe(struct pardevice * par_dev)825 static int pp_probe(struct pardevice *par_dev) 826 { 827 struct device_driver *drv = par_dev->dev.driver; 828 int len = strlen(drv->name); 829 830 if (strncmp(par_dev->name, drv->name, len)) 831 return -ENODEV; 832 833 return 0; 834 } 835 836 static struct parport_driver pp_driver = { 837 .name = CHRDEV, 838 .probe = pp_probe, 839 .match_port = pp_attach, 840 .detach = pp_detach, 841 }; 842 ppdev_init(void)843 static int __init ppdev_init(void) 844 { 845 int err = 0; 846 847 if (register_chrdev(PP_MAJOR, CHRDEV, &pp_fops)) { 848 pr_warn(CHRDEV ": unable to get major %d\n", PP_MAJOR); 849 return -EIO; 850 } 851 err = class_register(&ppdev_class); 852 if (err) 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_unregister(&ppdev_class); 866 out_chrdev: 867 unregister_chrdev(PP_MAJOR, CHRDEV); 868 out: 869 return err; 870 } 871 ppdev_cleanup(void)872 static void __exit ppdev_cleanup(void) 873 { 874 /* Clean up all parport stuff */ 875 parport_unregister_driver(&pp_driver); 876 class_unregister(&ppdev_class); 877 unregister_chrdev(PP_MAJOR, CHRDEV); 878 } 879 880 module_init(ppdev_init); 881 module_exit(ppdev_cleanup); 882 883 MODULE_DESCRIPTION("Support for user-space parallel port device drivers"); 884 MODULE_LICENSE("GPL"); 885 MODULE_ALIAS_CHARDEV_MAJOR(PP_MAJOR); 886