1/* This is the serial hardware link layer (HLL) for the Gigaset 307x isdn 2 * DECT base (aka Sinus 45 isdn) using the RS232 DECT data module M101, 3 * written as a line discipline. 4 * 5 * ===================================================================== 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of 9 * the License, or (at your option) any later version. 10 * ===================================================================== 11 */ 12 13#include "gigaset.h" 14#include <linux/module.h> 15#include <linux/moduleparam.h> 16#include <linux/platform_device.h> 17#include <linux/completion.h> 18 19/* Version Information */ 20#define DRIVER_AUTHOR "Tilman Schmidt" 21#define DRIVER_DESC "Serial Driver for Gigaset 307x using Siemens M101" 22 23#define GIGASET_MINORS 1 24#define GIGASET_MINOR 0 25#define GIGASET_MODULENAME "ser_gigaset" 26#define GIGASET_DEVNAME "ttyGS" 27 28/* length limit according to Siemens 3070usb-protokoll.doc ch. 2.1 */ 29#define IF_WRITEBUF 264 30 31MODULE_AUTHOR(DRIVER_AUTHOR); 32MODULE_DESCRIPTION(DRIVER_DESC); 33MODULE_LICENSE("GPL"); 34MODULE_ALIAS_LDISC(N_GIGASET_M101); 35 36static int startmode = SM_ISDN; 37module_param(startmode, int, S_IRUGO); 38MODULE_PARM_DESC(startmode, "initial operation mode"); 39static int cidmode = 1; 40module_param(cidmode, int, S_IRUGO); 41MODULE_PARM_DESC(cidmode, "stay in CID mode when idle"); 42 43static struct gigaset_driver *driver; 44 45struct ser_cardstate { 46 struct platform_device dev; 47 struct tty_struct *tty; 48 atomic_t refcnt; 49 struct completion dead_cmp; 50}; 51 52static struct platform_driver device_driver = { 53 .driver = { 54 .name = GIGASET_MODULENAME, 55 }, 56}; 57 58static void flush_send_queue(struct cardstate *); 59 60/* transmit data from current open skb 61 * result: number of bytes sent or error code < 0 62 */ 63static int write_modem(struct cardstate *cs) 64{ 65 struct tty_struct *tty = cs->hw.ser->tty; 66 struct bc_state *bcs = &cs->bcs[0]; /* only one channel */ 67 struct sk_buff *skb = bcs->tx_skb; 68 int sent = -EOPNOTSUPP; 69 70 if (!tty || !tty->driver || !skb) 71 return -EINVAL; 72 73 if (!skb->len) { 74 dev_kfree_skb_any(skb); 75 bcs->tx_skb = NULL; 76 return -EINVAL; 77 } 78 79 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 80 if (tty->ops->write) 81 sent = tty->ops->write(tty, skb->data, skb->len); 82 gig_dbg(DEBUG_OUTPUT, "write_modem: sent %d", sent); 83 if (sent < 0) { 84 /* error */ 85 flush_send_queue(cs); 86 return sent; 87 } 88 skb_pull(skb, sent); 89 if (!skb->len) { 90 /* skb sent completely */ 91 gigaset_skb_sent(bcs, skb); 92 93 gig_dbg(DEBUG_INTR, "kfree skb (Adr: %lx)!", 94 (unsigned long) skb); 95 dev_kfree_skb_any(skb); 96 bcs->tx_skb = NULL; 97 } 98 return sent; 99} 100 101/* 102 * transmit first queued command buffer 103 * result: number of bytes sent or error code < 0 104 */ 105static int send_cb(struct cardstate *cs) 106{ 107 struct tty_struct *tty = cs->hw.ser->tty; 108 struct cmdbuf_t *cb, *tcb; 109 unsigned long flags; 110 int sent = 0; 111 112 if (!tty || !tty->driver) 113 return -EFAULT; 114 115 cb = cs->cmdbuf; 116 if (!cb) 117 return 0; /* nothing to do */ 118 119 if (cb->len) { 120 set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 121 sent = tty->ops->write(tty, cb->buf + cb->offset, cb->len); 122 if (sent < 0) { 123 /* error */ 124 gig_dbg(DEBUG_OUTPUT, "send_cb: write error %d", sent); 125 flush_send_queue(cs); 126 return sent; 127 } 128 cb->offset += sent; 129 cb->len -= sent; 130 gig_dbg(DEBUG_OUTPUT, "send_cb: sent %d, left %u, queued %u", 131 sent, cb->len, cs->cmdbytes); 132 } 133 134 while (cb && !cb->len) { 135 spin_lock_irqsave(&cs->cmdlock, flags); 136 cs->cmdbytes -= cs->curlen; 137 tcb = cb; 138 cs->cmdbuf = cb = cb->next; 139 if (cb) { 140 cb->prev = NULL; 141 cs->curlen = cb->len; 142 } else { 143 cs->lastcmdbuf = NULL; 144 cs->curlen = 0; 145 } 146 spin_unlock_irqrestore(&cs->cmdlock, flags); 147 148 if (tcb->wake_tasklet) 149 tasklet_schedule(tcb->wake_tasklet); 150 kfree(tcb); 151 } 152 return sent; 153} 154 155/* 156 * send queue tasklet 157 * If there is already a skb opened, put data to the transfer buffer 158 * by calling "write_modem". 159 * Otherwise take a new skb out of the queue. 160 */ 161static void gigaset_modem_fill(unsigned long data) 162{ 163 struct cardstate *cs = (struct cardstate *) data; 164 struct bc_state *bcs; 165 struct sk_buff *nextskb; 166 int sent = 0; 167 168 if (!cs) { 169 gig_dbg(DEBUG_OUTPUT, "%s: no cardstate", __func__); 170 return; 171 } 172 bcs = cs->bcs; 173 if (!bcs) { 174 gig_dbg(DEBUG_OUTPUT, "%s: no cardstate", __func__); 175 return; 176 } 177 if (!bcs->tx_skb) { 178 /* no skb is being sent; send command if any */ 179 sent = send_cb(cs); 180 gig_dbg(DEBUG_OUTPUT, "%s: send_cb -> %d", __func__, sent); 181 if (sent) 182 /* something sent or error */ 183 return; 184 185 /* no command to send; get skb */ 186 nextskb = skb_dequeue(&bcs->squeue); 187 if (!nextskb) 188 /* no skb either, nothing to do */ 189 return; 190 bcs->tx_skb = nextskb; 191 192 gig_dbg(DEBUG_INTR, "Dequeued skb (Adr: %lx)", 193 (unsigned long) bcs->tx_skb); 194 } 195 196 /* send skb */ 197 gig_dbg(DEBUG_OUTPUT, "%s: tx_skb", __func__); 198 if (write_modem(cs) < 0) 199 gig_dbg(DEBUG_OUTPUT, "%s: write_modem failed", __func__); 200} 201 202/* 203 * throw away all data queued for sending 204 */ 205static void flush_send_queue(struct cardstate *cs) 206{ 207 struct sk_buff *skb; 208 struct cmdbuf_t *cb; 209 unsigned long flags; 210 211 /* command queue */ 212 spin_lock_irqsave(&cs->cmdlock, flags); 213 while ((cb = cs->cmdbuf) != NULL) { 214 cs->cmdbuf = cb->next; 215 if (cb->wake_tasklet) 216 tasklet_schedule(cb->wake_tasklet); 217 kfree(cb); 218 } 219 cs->cmdbuf = cs->lastcmdbuf = NULL; 220 cs->cmdbytes = cs->curlen = 0; 221 spin_unlock_irqrestore(&cs->cmdlock, flags); 222 223 /* data queue */ 224 if (cs->bcs->tx_skb) 225 dev_kfree_skb_any(cs->bcs->tx_skb); 226 while ((skb = skb_dequeue(&cs->bcs->squeue)) != NULL) 227 dev_kfree_skb_any(skb); 228} 229 230 231/* Gigaset Driver Interface */ 232/* ======================== */ 233 234/* 235 * queue an AT command string for transmission to the Gigaset device 236 * parameters: 237 * cs controller state structure 238 * buf buffer containing the string to send 239 * len number of characters to send 240 * wake_tasklet tasklet to run when transmission is complete, or NULL 241 * return value: 242 * number of bytes queued, or error code < 0 243 */ 244static int gigaset_write_cmd(struct cardstate *cs, struct cmdbuf_t *cb) 245{ 246 unsigned long flags; 247 248 gigaset_dbg_buffer(cs->mstate != MS_LOCKED ? 249 DEBUG_TRANSCMD : DEBUG_LOCKCMD, 250 "CMD Transmit", cb->len, cb->buf); 251 252 spin_lock_irqsave(&cs->cmdlock, flags); 253 cb->prev = cs->lastcmdbuf; 254 if (cs->lastcmdbuf) 255 cs->lastcmdbuf->next = cb; 256 else { 257 cs->cmdbuf = cb; 258 cs->curlen = cb->len; 259 } 260 cs->cmdbytes += cb->len; 261 cs->lastcmdbuf = cb; 262 spin_unlock_irqrestore(&cs->cmdlock, flags); 263 264 spin_lock_irqsave(&cs->lock, flags); 265 if (cs->connected) 266 tasklet_schedule(&cs->write_tasklet); 267 spin_unlock_irqrestore(&cs->lock, flags); 268 return cb->len; 269} 270 271/* 272 * tty_driver.write_room interface routine 273 * return number of characters the driver will accept to be written 274 * parameter: 275 * controller state structure 276 * return value: 277 * number of characters 278 */ 279static int gigaset_write_room(struct cardstate *cs) 280{ 281 unsigned bytes; 282 283 bytes = cs->cmdbytes; 284 return bytes < IF_WRITEBUF ? IF_WRITEBUF - bytes : 0; 285} 286 287/* 288 * tty_driver.chars_in_buffer interface routine 289 * return number of characters waiting to be sent 290 * parameter: 291 * controller state structure 292 * return value: 293 * number of characters 294 */ 295static int gigaset_chars_in_buffer(struct cardstate *cs) 296{ 297 return cs->cmdbytes; 298} 299 300/* 301 * implementation of ioctl(GIGASET_BRKCHARS) 302 * parameter: 303 * controller state structure 304 * return value: 305 * -EINVAL (unimplemented function) 306 */ 307static int gigaset_brkchars(struct cardstate *cs, const unsigned char buf[6]) 308{ 309 /* not implemented */ 310 return -EINVAL; 311} 312 313/* 314 * Open B channel 315 * Called by "do_action" in ev-layer.c 316 */ 317static int gigaset_init_bchannel(struct bc_state *bcs) 318{ 319 /* nothing to do for M10x */ 320 gigaset_bchannel_up(bcs); 321 return 0; 322} 323 324/* 325 * Close B channel 326 * Called by "do_action" in ev-layer.c 327 */ 328static int gigaset_close_bchannel(struct bc_state *bcs) 329{ 330 /* nothing to do for M10x */ 331 gigaset_bchannel_down(bcs); 332 return 0; 333} 334 335/* 336 * Set up B channel structure 337 * This is called by "gigaset_initcs" in common.c 338 */ 339static int gigaset_initbcshw(struct bc_state *bcs) 340{ 341 /* unused */ 342 bcs->hw.ser = NULL; 343 return 0; 344} 345 346/* 347 * Free B channel structure 348 * Called by "gigaset_freebcs" in common.c 349 */ 350static void gigaset_freebcshw(struct bc_state *bcs) 351{ 352 /* unused */ 353} 354 355/* 356 * Reinitialize B channel structure 357 * This is called by "bcs_reinit" in common.c 358 */ 359static void gigaset_reinitbcshw(struct bc_state *bcs) 360{ 361 /* nothing to do for M10x */ 362} 363 364/* 365 * Free hardware specific device data 366 * This will be called by "gigaset_freecs" in common.c 367 */ 368static void gigaset_freecshw(struct cardstate *cs) 369{ 370 tasklet_kill(&cs->write_tasklet); 371 if (!cs->hw.ser) 372 return; 373 dev_set_drvdata(&cs->hw.ser->dev.dev, NULL); 374 platform_device_unregister(&cs->hw.ser->dev); 375 kfree(cs->hw.ser); 376 cs->hw.ser = NULL; 377} 378 379static void gigaset_device_release(struct device *dev) 380{ 381 struct platform_device *pdev = to_platform_device(dev); 382 383 /* adapted from platform_device_release() in drivers/base/platform.c */ 384 kfree(dev->platform_data); 385 kfree(pdev->resource); 386} 387 388/* 389 * Set up hardware specific device data 390 * This is called by "gigaset_initcs" in common.c 391 */ 392static int gigaset_initcshw(struct cardstate *cs) 393{ 394 int rc; 395 struct ser_cardstate *scs; 396 397 scs = kzalloc(sizeof(struct ser_cardstate), GFP_KERNEL); 398 if (!scs) { 399 pr_err("out of memory\n"); 400 return -ENOMEM; 401 } 402 cs->hw.ser = scs; 403 404 cs->hw.ser->dev.name = GIGASET_MODULENAME; 405 cs->hw.ser->dev.id = cs->minor_index; 406 cs->hw.ser->dev.dev.release = gigaset_device_release; 407 rc = platform_device_register(&cs->hw.ser->dev); 408 if (rc != 0) { 409 pr_err("error %d registering platform device\n", rc); 410 kfree(cs->hw.ser); 411 cs->hw.ser = NULL; 412 return rc; 413 } 414 dev_set_drvdata(&cs->hw.ser->dev.dev, cs); 415 416 tasklet_init(&cs->write_tasklet, 417 gigaset_modem_fill, (unsigned long) cs); 418 return 0; 419} 420 421/* 422 * set modem control lines 423 * Parameters: 424 * card state structure 425 * modem control line state ([TIOCM_DTR]|[TIOCM_RTS]) 426 * Called by "gigaset_start" and "gigaset_enterconfigmode" in common.c 427 * and by "if_lock" and "if_termios" in interface.c 428 */ 429static int gigaset_set_modem_ctrl(struct cardstate *cs, unsigned old_state, 430 unsigned new_state) 431{ 432 struct tty_struct *tty = cs->hw.ser->tty; 433 unsigned int set, clear; 434 435 if (!tty || !tty->driver || !tty->ops->tiocmset) 436 return -EINVAL; 437 set = new_state & ~old_state; 438 clear = old_state & ~new_state; 439 if (!set && !clear) 440 return 0; 441 gig_dbg(DEBUG_IF, "tiocmset set %x clear %x", set, clear); 442 return tty->ops->tiocmset(tty, set, clear); 443} 444 445static int gigaset_baud_rate(struct cardstate *cs, unsigned cflag) 446{ 447 return -EINVAL; 448} 449 450static int gigaset_set_line_ctrl(struct cardstate *cs, unsigned cflag) 451{ 452 return -EINVAL; 453} 454 455static const struct gigaset_ops ops = { 456 gigaset_write_cmd, 457 gigaset_write_room, 458 gigaset_chars_in_buffer, 459 gigaset_brkchars, 460 gigaset_init_bchannel, 461 gigaset_close_bchannel, 462 gigaset_initbcshw, 463 gigaset_freebcshw, 464 gigaset_reinitbcshw, 465 gigaset_initcshw, 466 gigaset_freecshw, 467 gigaset_set_modem_ctrl, 468 gigaset_baud_rate, 469 gigaset_set_line_ctrl, 470 gigaset_m10x_send_skb, /* asyncdata.c */ 471 gigaset_m10x_input, /* asyncdata.c */ 472}; 473 474 475/* Line Discipline Interface */ 476/* ========================= */ 477 478/* helper functions for cardstate refcounting */ 479static struct cardstate *cs_get(struct tty_struct *tty) 480{ 481 struct cardstate *cs = tty->disc_data; 482 483 if (!cs || !cs->hw.ser) { 484 gig_dbg(DEBUG_ANY, "%s: no cardstate", __func__); 485 return NULL; 486 } 487 atomic_inc(&cs->hw.ser->refcnt); 488 return cs; 489} 490 491static void cs_put(struct cardstate *cs) 492{ 493 if (atomic_dec_and_test(&cs->hw.ser->refcnt)) 494 complete(&cs->hw.ser->dead_cmp); 495} 496 497/* 498 * Called by the tty driver when the line discipline is pushed onto the tty. 499 * Called in process context. 500 */ 501static int 502gigaset_tty_open(struct tty_struct *tty) 503{ 504 struct cardstate *cs; 505 int rc; 506 507 gig_dbg(DEBUG_INIT, "Starting HLL for Gigaset M101"); 508 509 pr_info(DRIVER_DESC "\n"); 510 511 if (!driver) { 512 pr_err("%s: no driver structure\n", __func__); 513 return -ENODEV; 514 } 515 516 /* allocate memory for our device state and initialize it */ 517 cs = gigaset_initcs(driver, 1, 1, 0, cidmode, GIGASET_MODULENAME); 518 if (!cs) { 519 rc = -ENODEV; 520 goto error; 521 } 522 523 cs->dev = &cs->hw.ser->dev.dev; 524 cs->hw.ser->tty = tty; 525 atomic_set(&cs->hw.ser->refcnt, 1); 526 init_completion(&cs->hw.ser->dead_cmp); 527 528 tty->disc_data = cs; 529 530 /* OK.. Initialization of the datastructures and the HW is done.. Now 531 * startup system and notify the LL that we are ready to run 532 */ 533 if (startmode == SM_LOCKED) 534 cs->mstate = MS_LOCKED; 535 rc = gigaset_start(cs); 536 if (rc < 0) { 537 tasklet_kill(&cs->write_tasklet); 538 goto error; 539 } 540 541 gig_dbg(DEBUG_INIT, "Startup of HLL done"); 542 return 0; 543 544error: 545 gig_dbg(DEBUG_INIT, "Startup of HLL failed"); 546 tty->disc_data = NULL; 547 gigaset_freecs(cs); 548 return rc; 549} 550 551/* 552 * Called by the tty driver when the line discipline is removed. 553 * Called from process context. 554 */ 555static void 556gigaset_tty_close(struct tty_struct *tty) 557{ 558 struct cardstate *cs = tty->disc_data; 559 560 gig_dbg(DEBUG_INIT, "Stopping HLL for Gigaset M101"); 561 562 if (!cs) { 563 gig_dbg(DEBUG_INIT, "%s: no cardstate", __func__); 564 return; 565 } 566 567 /* prevent other callers from entering ldisc methods */ 568 tty->disc_data = NULL; 569 570 if (!cs->hw.ser) 571 pr_err("%s: no hw cardstate\n", __func__); 572 else { 573 /* wait for running methods to finish */ 574 if (!atomic_dec_and_test(&cs->hw.ser->refcnt)) 575 wait_for_completion(&cs->hw.ser->dead_cmp); 576 } 577 578 /* stop operations */ 579 gigaset_stop(cs); 580 tasklet_kill(&cs->write_tasklet); 581 flush_send_queue(cs); 582 cs->dev = NULL; 583 gigaset_freecs(cs); 584 585 gig_dbg(DEBUG_INIT, "Shutdown of HLL done"); 586} 587 588/* 589 * Called by the tty driver when the tty line is hung up. 590 * Wait for I/O to driver to complete and unregister ISDN device. 591 * This is already done by the close routine, so just call that. 592 * Called from process context. 593 */ 594static int gigaset_tty_hangup(struct tty_struct *tty) 595{ 596 gigaset_tty_close(tty); 597 return 0; 598} 599 600/* 601 * Read on the tty. 602 * Unused, received data goes only to the Gigaset driver. 603 */ 604static ssize_t 605gigaset_tty_read(struct tty_struct *tty, struct file *file, 606 unsigned char __user *buf, size_t count) 607{ 608 return -EAGAIN; 609} 610 611/* 612 * Write on the tty. 613 * Unused, transmit data comes only from the Gigaset driver. 614 */ 615static ssize_t 616gigaset_tty_write(struct tty_struct *tty, struct file *file, 617 const unsigned char *buf, size_t count) 618{ 619 return -EAGAIN; 620} 621 622/* 623 * Ioctl on the tty. 624 * Called in process context only. 625 * May be re-entered by multiple ioctl calling threads. 626 */ 627static int 628gigaset_tty_ioctl(struct tty_struct *tty, struct file *file, 629 unsigned int cmd, unsigned long arg) 630{ 631 struct cardstate *cs = cs_get(tty); 632 int rc, val; 633 int __user *p = (int __user *)arg; 634 635 if (!cs) 636 return -ENXIO; 637 638 switch (cmd) { 639 640 case FIONREAD: 641 /* unused, always return zero */ 642 val = 0; 643 rc = put_user(val, p); 644 break; 645 646 case TCFLSH: 647 /* flush our buffers and the serial port's buffer */ 648 switch (arg) { 649 case TCIFLUSH: 650 /* no own input buffer to flush */ 651 break; 652 case TCIOFLUSH: 653 case TCOFLUSH: 654 flush_send_queue(cs); 655 break; 656 } 657 /* Pass through */ 658 659 default: 660 /* pass through to underlying serial device */ 661 rc = n_tty_ioctl_helper(tty, file, cmd, arg); 662 break; 663 } 664 cs_put(cs); 665 return rc; 666} 667 668/* 669 * Called by the tty driver when a block of data has been received. 670 * Will not be re-entered while running but other ldisc functions 671 * may be called in parallel. 672 * Can be called from hard interrupt level as well as soft interrupt 673 * level or mainline. 674 * Parameters: 675 * tty tty structure 676 * buf buffer containing received characters 677 * cflags buffer containing error flags for received characters (ignored) 678 * count number of received characters 679 */ 680static void 681gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf, 682 char *cflags, int count) 683{ 684 struct cardstate *cs = cs_get(tty); 685 unsigned tail, head, n; 686 struct inbuf_t *inbuf; 687 688 if (!cs) 689 return; 690 inbuf = cs->inbuf; 691 if (!inbuf) { 692 dev_err(cs->dev, "%s: no inbuf\n", __func__); 693 cs_put(cs); 694 return; 695 } 696 697 tail = inbuf->tail; 698 head = inbuf->head; 699 gig_dbg(DEBUG_INTR, "buffer state: %u -> %u, receive %u bytes", 700 head, tail, count); 701 702 if (head <= tail) { 703 /* possible buffer wraparound */ 704 n = min_t(unsigned, count, RBUFSIZE - tail); 705 memcpy(inbuf->data + tail, buf, n); 706 tail = (tail + n) % RBUFSIZE; 707 buf += n; 708 count -= n; 709 } 710 711 if (count > 0) { 712 /* tail < head and some data left */ 713 n = head - tail - 1; 714 if (count > n) { 715 dev_err(cs->dev, 716 "inbuf overflow, discarding %d bytes\n", 717 count - n); 718 count = n; 719 } 720 memcpy(inbuf->data + tail, buf, count); 721 tail += count; 722 } 723 724 gig_dbg(DEBUG_INTR, "setting tail to %u", tail); 725 inbuf->tail = tail; 726 727 /* Everything was received .. Push data into handler */ 728 gig_dbg(DEBUG_INTR, "%s-->BH", __func__); 729 gigaset_schedule_event(cs); 730 cs_put(cs); 731} 732 733/* 734 * Called by the tty driver when there's room for more data to send. 735 */ 736static void 737gigaset_tty_wakeup(struct tty_struct *tty) 738{ 739 struct cardstate *cs = cs_get(tty); 740 741 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 742 if (!cs) 743 return; 744 tasklet_schedule(&cs->write_tasklet); 745 cs_put(cs); 746} 747 748static struct tty_ldisc_ops gigaset_ldisc = { 749 .owner = THIS_MODULE, 750 .magic = TTY_LDISC_MAGIC, 751 .name = "ser_gigaset", 752 .open = gigaset_tty_open, 753 .close = gigaset_tty_close, 754 .hangup = gigaset_tty_hangup, 755 .read = gigaset_tty_read, 756 .write = gigaset_tty_write, 757 .ioctl = gigaset_tty_ioctl, 758 .receive_buf = gigaset_tty_receive, 759 .write_wakeup = gigaset_tty_wakeup, 760}; 761 762 763/* Initialization / Shutdown */ 764/* ========================= */ 765 766static int __init ser_gigaset_init(void) 767{ 768 int rc; 769 770 gig_dbg(DEBUG_INIT, "%s", __func__); 771 rc = platform_driver_register(&device_driver); 772 if (rc != 0) { 773 pr_err("error %d registering platform driver\n", rc); 774 return rc; 775 } 776 777 /* allocate memory for our driver state and initialize it */ 778 driver = gigaset_initdriver(GIGASET_MINOR, GIGASET_MINORS, 779 GIGASET_MODULENAME, GIGASET_DEVNAME, 780 &ops, THIS_MODULE); 781 if (!driver) 782 goto error; 783 784 rc = tty_register_ldisc(N_GIGASET_M101, &gigaset_ldisc); 785 if (rc != 0) { 786 pr_err("error %d registering line discipline\n", rc); 787 goto error; 788 } 789 790 return 0; 791 792error: 793 if (driver) { 794 gigaset_freedriver(driver); 795 driver = NULL; 796 } 797 platform_driver_unregister(&device_driver); 798 return rc; 799} 800 801static void __exit ser_gigaset_exit(void) 802{ 803 int rc; 804 805 gig_dbg(DEBUG_INIT, "%s", __func__); 806 807 if (driver) { 808 gigaset_freedriver(driver); 809 driver = NULL; 810 } 811 812 rc = tty_unregister_ldisc(N_GIGASET_M101); 813 if (rc != 0) 814 pr_err("error %d unregistering line discipline\n", rc); 815 816 platform_driver_unregister(&device_driver); 817} 818 819module_init(ser_gigaset_init); 820module_exit(ser_gigaset_exit); 821