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 1; 344} 345 346/* 347 * Free B channel structure 348 * Called by "gigaset_freebcs" in common.c 349 */ 350static int gigaset_freebcshw(struct bc_state *bcs) 351{ 352 /* unused */ 353 return 1; 354} 355 356/* 357 * Reinitialize B channel structure 358 * This is called by "bcs_reinit" in common.c 359 */ 360static void gigaset_reinitbcshw(struct bc_state *bcs) 361{ 362 /* nothing to do for M10x */ 363} 364 365/* 366 * Free hardware specific device data 367 * This will be called by "gigaset_freecs" in common.c 368 */ 369static void gigaset_freecshw(struct cardstate *cs) 370{ 371 tasklet_kill(&cs->write_tasklet); 372 if (!cs->hw.ser) 373 return; 374 dev_set_drvdata(&cs->hw.ser->dev.dev, NULL); 375 platform_device_unregister(&cs->hw.ser->dev); 376 kfree(cs->hw.ser); 377 cs->hw.ser = NULL; 378} 379 380static void gigaset_device_release(struct device *dev) 381{ 382 struct platform_device *pdev = to_platform_device(dev); 383 384 /* adapted from platform_device_release() in drivers/base/platform.c */ 385 kfree(dev->platform_data); 386 kfree(pdev->resource); 387} 388 389/* 390 * Set up hardware specific device data 391 * This is called by "gigaset_initcs" in common.c 392 */ 393static int gigaset_initcshw(struct cardstate *cs) 394{ 395 int rc; 396 struct ser_cardstate *scs; 397 398 scs = kzalloc(sizeof(struct ser_cardstate), GFP_KERNEL); 399 if (!scs) { 400 pr_err("out of memory\n"); 401 return 0; 402 } 403 cs->hw.ser = scs; 404 405 cs->hw.ser->dev.name = GIGASET_MODULENAME; 406 cs->hw.ser->dev.id = cs->minor_index; 407 cs->hw.ser->dev.dev.release = gigaset_device_release; 408 rc = platform_device_register(&cs->hw.ser->dev); 409 if (rc != 0) { 410 pr_err("error %d registering platform device\n", rc); 411 kfree(cs->hw.ser); 412 cs->hw.ser = NULL; 413 return 0; 414 } 415 dev_set_drvdata(&cs->hw.ser->dev.dev, cs); 416 417 tasklet_init(&cs->write_tasklet, 418 gigaset_modem_fill, (unsigned long) cs); 419 return 1; 420} 421 422/* 423 * set modem control lines 424 * Parameters: 425 * card state structure 426 * modem control line state ([TIOCM_DTR]|[TIOCM_RTS]) 427 * Called by "gigaset_start" and "gigaset_enterconfigmode" in common.c 428 * and by "if_lock" and "if_termios" in interface.c 429 */ 430static int gigaset_set_modem_ctrl(struct cardstate *cs, unsigned old_state, 431 unsigned new_state) 432{ 433 struct tty_struct *tty = cs->hw.ser->tty; 434 unsigned int set, clear; 435 436 if (!tty || !tty->driver || !tty->ops->tiocmset) 437 return -EINVAL; 438 set = new_state & ~old_state; 439 clear = old_state & ~new_state; 440 if (!set && !clear) 441 return 0; 442 gig_dbg(DEBUG_IF, "tiocmset set %x clear %x", set, clear); 443 return tty->ops->tiocmset(tty, NULL, set, clear); 444} 445 446static int gigaset_baud_rate(struct cardstate *cs, unsigned cflag) 447{ 448 return -EINVAL; 449} 450 451static int gigaset_set_line_ctrl(struct cardstate *cs, unsigned cflag) 452{ 453 return -EINVAL; 454} 455 456static const struct gigaset_ops ops = { 457 gigaset_write_cmd, 458 gigaset_write_room, 459 gigaset_chars_in_buffer, 460 gigaset_brkchars, 461 gigaset_init_bchannel, 462 gigaset_close_bchannel, 463 gigaset_initbcshw, 464 gigaset_freebcshw, 465 gigaset_reinitbcshw, 466 gigaset_initcshw, 467 gigaset_freecshw, 468 gigaset_set_modem_ctrl, 469 gigaset_baud_rate, 470 gigaset_set_line_ctrl, 471 gigaset_m10x_send_skb, /* asyncdata.c */ 472 gigaset_m10x_input, /* asyncdata.c */ 473}; 474 475 476/* Line Discipline Interface */ 477/* ========================= */ 478 479/* helper functions for cardstate refcounting */ 480static struct cardstate *cs_get(struct tty_struct *tty) 481{ 482 struct cardstate *cs = tty->disc_data; 483 484 if (!cs || !cs->hw.ser) { 485 gig_dbg(DEBUG_ANY, "%s: no cardstate", __func__); 486 return NULL; 487 } 488 atomic_inc(&cs->hw.ser->refcnt); 489 return cs; 490} 491 492static void cs_put(struct cardstate *cs) 493{ 494 if (atomic_dec_and_test(&cs->hw.ser->refcnt)) 495 complete(&cs->hw.ser->dead_cmp); 496} 497 498/* 499 * Called by the tty driver when the line discipline is pushed onto the tty. 500 * Called in process context. 501 */ 502static int 503gigaset_tty_open(struct tty_struct *tty) 504{ 505 struct cardstate *cs; 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 intialize it */ 517 cs = gigaset_initcs(driver, 1, 1, 0, cidmode, GIGASET_MODULENAME); 518 if (!cs) 519 goto error; 520 521 cs->dev = &cs->hw.ser->dev.dev; 522 cs->hw.ser->tty = tty; 523 atomic_set(&cs->hw.ser->refcnt, 1); 524 init_completion(&cs->hw.ser->dead_cmp); 525 526 tty->disc_data = cs; 527 528 /* OK.. Initialization of the datastructures and the HW is done.. Now 529 * startup system and notify the LL that we are ready to run 530 */ 531 if (startmode == SM_LOCKED) 532 cs->mstate = MS_LOCKED; 533 if (!gigaset_start(cs)) { 534 tasklet_kill(&cs->write_tasklet); 535 goto error; 536 } 537 538 gig_dbg(DEBUG_INIT, "Startup of HLL done"); 539 return 0; 540 541error: 542 gig_dbg(DEBUG_INIT, "Startup of HLL failed"); 543 tty->disc_data = NULL; 544 gigaset_freecs(cs); 545 return -ENODEV; 546} 547 548/* 549 * Called by the tty driver when the line discipline is removed. 550 * Called from process context. 551 */ 552static void 553gigaset_tty_close(struct tty_struct *tty) 554{ 555 struct cardstate *cs = tty->disc_data; 556 557 gig_dbg(DEBUG_INIT, "Stopping HLL for Gigaset M101"); 558 559 if (!cs) { 560 gig_dbg(DEBUG_INIT, "%s: no cardstate", __func__); 561 return; 562 } 563 564 /* prevent other callers from entering ldisc methods */ 565 tty->disc_data = NULL; 566 567 if (!cs->hw.ser) 568 pr_err("%s: no hw cardstate\n", __func__); 569 else { 570 /* wait for running methods to finish */ 571 if (!atomic_dec_and_test(&cs->hw.ser->refcnt)) 572 wait_for_completion(&cs->hw.ser->dead_cmp); 573 } 574 575 /* stop operations */ 576 gigaset_stop(cs); 577 tasklet_kill(&cs->write_tasklet); 578 flush_send_queue(cs); 579 cs->dev = NULL; 580 gigaset_freecs(cs); 581 582 gig_dbg(DEBUG_INIT, "Shutdown of HLL done"); 583} 584 585/* 586 * Called by the tty driver when the tty line is hung up. 587 * Wait for I/O to driver to complete and unregister ISDN device. 588 * This is already done by the close routine, so just call that. 589 * Called from process context. 590 */ 591static int gigaset_tty_hangup(struct tty_struct *tty) 592{ 593 gigaset_tty_close(tty); 594 return 0; 595} 596 597/* 598 * Read on the tty. 599 * Unused, received data goes only to the Gigaset driver. 600 */ 601static ssize_t 602gigaset_tty_read(struct tty_struct *tty, struct file *file, 603 unsigned char __user *buf, size_t count) 604{ 605 return -EAGAIN; 606} 607 608/* 609 * Write on the tty. 610 * Unused, transmit data comes only from the Gigaset driver. 611 */ 612static ssize_t 613gigaset_tty_write(struct tty_struct *tty, struct file *file, 614 const unsigned char *buf, size_t count) 615{ 616 return -EAGAIN; 617} 618 619/* 620 * Ioctl on the tty. 621 * Called in process context only. 622 * May be re-entered by multiple ioctl calling threads. 623 */ 624static int 625gigaset_tty_ioctl(struct tty_struct *tty, struct file *file, 626 unsigned int cmd, unsigned long arg) 627{ 628 struct cardstate *cs = cs_get(tty); 629 int rc, val; 630 int __user *p = (int __user *)arg; 631 632 if (!cs) 633 return -ENXIO; 634 635 switch (cmd) { 636 637 case FIONREAD: 638 /* unused, always return zero */ 639 val = 0; 640 rc = put_user(val, p); 641 break; 642 643 case TCFLSH: 644 /* flush our buffers and the serial port's buffer */ 645 switch (arg) { 646 case TCIFLUSH: 647 /* no own input buffer to flush */ 648 break; 649 case TCIOFLUSH: 650 case TCOFLUSH: 651 flush_send_queue(cs); 652 break; 653 } 654 /* Pass through */ 655 656 default: 657 /* pass through to underlying serial device */ 658 rc = n_tty_ioctl_helper(tty, file, cmd, arg); 659 break; 660 } 661 cs_put(cs); 662 return rc; 663} 664 665/* 666 * Called by the tty driver when a block of data has been received. 667 * Will not be re-entered while running but other ldisc functions 668 * may be called in parallel. 669 * Can be called from hard interrupt level as well as soft interrupt 670 * level or mainline. 671 * Parameters: 672 * tty tty structure 673 * buf buffer containing received characters 674 * cflags buffer containing error flags for received characters (ignored) 675 * count number of received characters 676 */ 677static void 678gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf, 679 char *cflags, int count) 680{ 681 struct cardstate *cs = cs_get(tty); 682 unsigned tail, head, n; 683 struct inbuf_t *inbuf; 684 685 if (!cs) 686 return; 687 inbuf = cs->inbuf; 688 if (!inbuf) { 689 dev_err(cs->dev, "%s: no inbuf\n", __func__); 690 cs_put(cs); 691 return; 692 } 693 694 tail = inbuf->tail; 695 head = inbuf->head; 696 gig_dbg(DEBUG_INTR, "buffer state: %u -> %u, receive %u bytes", 697 head, tail, count); 698 699 if (head <= tail) { 700 /* possible buffer wraparound */ 701 n = min_t(unsigned, count, RBUFSIZE - tail); 702 memcpy(inbuf->data + tail, buf, n); 703 tail = (tail + n) % RBUFSIZE; 704 buf += n; 705 count -= n; 706 } 707 708 if (count > 0) { 709 /* tail < head and some data left */ 710 n = head - tail - 1; 711 if (count > n) { 712 dev_err(cs->dev, 713 "inbuf overflow, discarding %d bytes\n", 714 count - n); 715 count = n; 716 } 717 memcpy(inbuf->data + tail, buf, count); 718 tail += count; 719 } 720 721 gig_dbg(DEBUG_INTR, "setting tail to %u", tail); 722 inbuf->tail = tail; 723 724 /* Everything was received .. Push data into handler */ 725 gig_dbg(DEBUG_INTR, "%s-->BH", __func__); 726 gigaset_schedule_event(cs); 727 cs_put(cs); 728} 729 730/* 731 * Called by the tty driver when there's room for more data to send. 732 */ 733static void 734gigaset_tty_wakeup(struct tty_struct *tty) 735{ 736 struct cardstate *cs = cs_get(tty); 737 738 clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); 739 if (!cs) 740 return; 741 tasklet_schedule(&cs->write_tasklet); 742 cs_put(cs); 743} 744 745static struct tty_ldisc_ops gigaset_ldisc = { 746 .owner = THIS_MODULE, 747 .magic = TTY_LDISC_MAGIC, 748 .name = "ser_gigaset", 749 .open = gigaset_tty_open, 750 .close = gigaset_tty_close, 751 .hangup = gigaset_tty_hangup, 752 .read = gigaset_tty_read, 753 .write = gigaset_tty_write, 754 .ioctl = gigaset_tty_ioctl, 755 .receive_buf = gigaset_tty_receive, 756 .write_wakeup = gigaset_tty_wakeup, 757}; 758 759 760/* Initialization / Shutdown */ 761/* ========================= */ 762 763static int __init ser_gigaset_init(void) 764{ 765 int rc; 766 767 gig_dbg(DEBUG_INIT, "%s", __func__); 768 rc = platform_driver_register(&device_driver); 769 if (rc != 0) { 770 pr_err("error %d registering platform driver\n", rc); 771 return rc; 772 } 773 774 /* allocate memory for our driver state and intialize it */ 775 driver = gigaset_initdriver(GIGASET_MINOR, GIGASET_MINORS, 776 GIGASET_MODULENAME, GIGASET_DEVNAME, 777 &ops, THIS_MODULE); 778 if (!driver) 779 goto error; 780 781 rc = tty_register_ldisc(N_GIGASET_M101, &gigaset_ldisc); 782 if (rc != 0) { 783 pr_err("error %d registering line discipline\n", rc); 784 goto error; 785 } 786 787 return 0; 788 789error: 790 if (driver) { 791 gigaset_freedriver(driver); 792 driver = NULL; 793 } 794 platform_driver_unregister(&device_driver); 795 return rc; 796} 797 798static void __exit ser_gigaset_exit(void) 799{ 800 int rc; 801 802 gig_dbg(DEBUG_INIT, "%s", __func__); 803 804 if (driver) { 805 gigaset_freedriver(driver); 806 driver = NULL; 807 } 808 809 rc = tty_unregister_ldisc(N_GIGASET_M101); 810 if (rc != 0) 811 pr_err("error %d unregistering line discipline\n", rc); 812 813 platform_driver_unregister(&device_driver); 814} 815 816module_init(ser_gigaset_init); 817module_exit(ser_gigaset_exit); 818