1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * USB Serial Converter driver
   4 *
   5 * Copyright (C) 2009 - 2013 Johan Hovold (jhovold@gmail.com)
   6 * Copyright (C) 1999 - 2012 Greg Kroah-Hartman (greg@kroah.com)
   7 * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
   8 * Copyright (C) 2000 Al Borchers (borchers@steinerpoint.com)
   9 *
  10 * This driver was originally based on the ACM driver by Armin Fuerst (which was
  11 * based on a driver by Brad Keryan)
  12 *
  13 * See Documentation/usb/usb-serial.rst for more information on using this
  14 * driver
  15 */
  16
  17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  18
  19#include <linux/kernel.h>
  20#include <linux/errno.h>
  21#include <linux/init.h>
  22#include <linux/slab.h>
  23#include <linux/tty.h>
  24#include <linux/tty_driver.h>
  25#include <linux/tty_flip.h>
  26#include <linux/module.h>
  27#include <linux/moduleparam.h>
  28#include <linux/seq_file.h>
  29#include <linux/spinlock.h>
  30#include <linux/mutex.h>
  31#include <linux/list.h>
  32#include <linux/uaccess.h>
  33#include <linux/serial.h>
  34#include <linux/usb.h>
  35#include <linux/usb/serial.h>
  36#include <linux/kfifo.h>
  37#include <linux/idr.h>
  38
  39#define DRIVER_AUTHOR "Greg Kroah-Hartman <gregkh@linuxfoundation.org>"
  40#define DRIVER_DESC "USB Serial Driver core"
  41
  42#define USB_SERIAL_TTY_MAJOR	188
  43#define USB_SERIAL_TTY_MINORS	512	/* should be enough for a while */
  44
  45/* There is no MODULE_DEVICE_TABLE for usbserial.c.  Instead
  46   the MODULE_DEVICE_TABLE declarations in each serial driver
  47   cause the "hotplug" program to pull in whatever module is necessary
  48   via modprobe, and modprobe will load usbserial because the serial
  49   drivers depend on it.
  50*/
  51
  52static DEFINE_IDR(serial_minors);
  53static DEFINE_MUTEX(table_lock);
  54static LIST_HEAD(usb_serial_driver_list);
  55
  56/*
  57 * Look up the serial port structure.  If it is found and it hasn't been
  58 * disconnected, return with the parent usb_serial structure's disc_mutex held
  59 * and its refcount incremented.  Otherwise return NULL.
  60 */
  61struct usb_serial_port *usb_serial_port_get_by_minor(unsigned minor)
  62{
  63	struct usb_serial *serial;
  64	struct usb_serial_port *port;
  65
  66	mutex_lock(&table_lock);
  67	port = idr_find(&serial_minors, minor);
  68	if (!port)
  69		goto exit;
  70
  71	serial = port->serial;
  72	mutex_lock(&serial->disc_mutex);
  73	if (serial->disconnected) {
  74		mutex_unlock(&serial->disc_mutex);
  75		port = NULL;
  76	} else {
  77		kref_get(&serial->kref);
  78	}
  79exit:
  80	mutex_unlock(&table_lock);
  81	return port;
  82}
  83
  84static int allocate_minors(struct usb_serial *serial, int num_ports)
  85{
  86	struct usb_serial_port *port;
  87	unsigned int i, j;
  88	int minor;
  89
  90	dev_dbg(&serial->interface->dev, "%s %d\n", __func__, num_ports);
  91
  92	mutex_lock(&table_lock);
  93	for (i = 0; i < num_ports; ++i) {
  94		port = serial->port[i];
  95		minor = idr_alloc(&serial_minors, port, 0,
  96					USB_SERIAL_TTY_MINORS, GFP_KERNEL);
  97		if (minor < 0)
  98			goto error;
  99		port->minor = minor;
 100		port->port_number = i;
 101	}
 102	serial->minors_reserved = 1;
 103	mutex_unlock(&table_lock);
 104	return 0;
 105error:
 106	/* unwind the already allocated minors */
 107	for (j = 0; j < i; ++j)
 108		idr_remove(&serial_minors, serial->port[j]->minor);
 109	mutex_unlock(&table_lock);
 110	return minor;
 111}
 112
 113static void release_minors(struct usb_serial *serial)
 114{
 115	int i;
 116
 117	mutex_lock(&table_lock);
 118	for (i = 0; i < serial->num_ports; ++i)
 119		idr_remove(&serial_minors, serial->port[i]->minor);
 120	mutex_unlock(&table_lock);
 121	serial->minors_reserved = 0;
 122}
 123
 124int usb_serial_claim_interface(struct usb_serial *serial, struct usb_interface *intf)
 125{
 126	struct usb_driver *driver = serial->type->usb_driver;
 127	int ret;
 128
 129	if (serial->sibling)
 130		return -EBUSY;
 131
 132	ret = usb_driver_claim_interface(driver, intf, serial);
 133	if (ret) {
 134		dev_err(&serial->interface->dev,
 135				"failed to claim sibling interface: %d\n", ret);
 136		return ret;
 137	}
 138
 139	serial->sibling = intf;
 140
 141	return 0;
 142}
 143EXPORT_SYMBOL_GPL(usb_serial_claim_interface);
 144
 145static void release_sibling(struct usb_serial *serial, struct usb_interface *intf)
 146{
 147	struct usb_driver *driver = serial->type->usb_driver;
 148	struct usb_interface *sibling;
 149
 150	if (!serial->sibling)
 151		return;
 152
 153	if (intf == serial->sibling)
 154		sibling = serial->interface;
 155	else
 156		sibling = serial->sibling;
 157
 158	usb_set_intfdata(sibling, NULL);
 159	usb_driver_release_interface(driver, sibling);
 160}
 161
 162static void destroy_serial(struct kref *kref)
 163{
 164	struct usb_serial *serial;
 165	struct usb_serial_port *port;
 166	int i;
 167
 168	serial = to_usb_serial(kref);
 169
 170	/* return the minor range that this device had */
 171	if (serial->minors_reserved)
 172		release_minors(serial);
 173
 174	if (serial->attached && serial->type->release)
 175		serial->type->release(serial);
 176
 177	/* Now that nothing is using the ports, they can be freed */
 178	for (i = 0; i < serial->num_port_pointers; ++i) {
 179		port = serial->port[i];
 180		if (port) {
 181			port->serial = NULL;
 182			put_device(&port->dev);
 183		}
 184	}
 185
 186	usb_put_intf(serial->interface);
 187	usb_put_dev(serial->dev);
 188	kfree(serial);
 189}
 190
 191void usb_serial_put(struct usb_serial *serial)
 192{
 193	kref_put(&serial->kref, destroy_serial);
 194}
 195
 196/*****************************************************************************
 197 * Driver tty interface functions
 198 *****************************************************************************/
 199
 200/**
 201 * serial_install - install tty
 202 * @driver: the driver (USB in our case)
 203 * @tty: the tty being created
 204 *
 205 * Initialise the termios structure for this tty.  We use the default
 206 * USB serial settings but permit them to be overridden by
 207 * serial->type->init_termios on first open.
 208 *
 209 * This is the first place a new tty gets used.  Hence this is where we
 210 * acquire references to the usb_serial structure and the driver module,
 211 * where we store a pointer to the port.  All these actions are reversed
 212 * in serial_cleanup().
 213 */
 214static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
 215{
 216	int idx = tty->index;
 217	struct usb_serial *serial;
 218	struct usb_serial_port *port;
 219	bool init_termios;
 220	int retval = -ENODEV;
 221
 222	port = usb_serial_port_get_by_minor(idx);
 223	if (!port)
 224		return retval;
 225
 226	serial = port->serial;
 227	if (!try_module_get(serial->type->driver.owner))
 228		goto err_put_serial;
 229
 230	init_termios = (driver->termios[idx] == NULL);
 231
 232	retval = tty_standard_install(driver, tty);
 233	if (retval)
 234		goto err_put_module;
 235
 236	mutex_unlock(&serial->disc_mutex);
 237
 238	/* allow the driver to update the initial settings */
 239	if (init_termios && serial->type->init_termios)
 240		serial->type->init_termios(tty);
 241
 242	tty->driver_data = port;
 243
 244	return retval;
 245
 246err_put_module:
 247	module_put(serial->type->driver.owner);
 248err_put_serial:
 249	usb_serial_put(serial);
 250	mutex_unlock(&serial->disc_mutex);
 251	return retval;
 252}
 253
 254static int serial_port_activate(struct tty_port *tport, struct tty_struct *tty)
 255{
 256	struct usb_serial_port *port =
 257		container_of(tport, struct usb_serial_port, port);
 258	struct usb_serial *serial = port->serial;
 259	int retval;
 260
 261	mutex_lock(&serial->disc_mutex);
 262	if (serial->disconnected) {
 263		retval = -ENODEV;
 264		goto out_unlock;
 265	}
 266
 267	retval = usb_autopm_get_interface(serial->interface);
 268	if (retval)
 269		goto out_unlock;
 270
 271	retval = port->serial->type->open(tty, port);
 272	if (retval)
 273		usb_autopm_put_interface(serial->interface);
 274out_unlock:
 275	mutex_unlock(&serial->disc_mutex);
 276
 277	if (retval < 0)
 278		retval = usb_translate_errors(retval);
 279
 280	return retval;
 281}
 282
 283static int serial_open(struct tty_struct *tty, struct file *filp)
 284{
 285	struct usb_serial_port *port = tty->driver_data;
 286
 287	dev_dbg(&port->dev, "%s\n", __func__);
 288
 289	return tty_port_open(&port->port, tty, filp);
 290}
 291
 292/**
 293 * serial_port_shutdown - shut down hardware
 294 * @tport: tty port to shut down
 295 *
 296 * Shut down a USB serial port. Serialized against activate by the
 297 * tport mutex and kept to matching open/close pairs
 298 * of calls by the tty-port initialized flag.
 299 *
 300 * Not called if tty is console.
 301 */
 302static void serial_port_shutdown(struct tty_port *tport)
 303{
 304	struct usb_serial_port *port =
 305		container_of(tport, struct usb_serial_port, port);
 306	struct usb_serial_driver *drv = port->serial->type;
 307
 308	if (drv->close)
 309		drv->close(port);
 310
 311	usb_autopm_put_interface(port->serial->interface);
 312}
 313
 314static void serial_hangup(struct tty_struct *tty)
 315{
 316	struct usb_serial_port *port = tty->driver_data;
 317
 318	dev_dbg(&port->dev, "%s\n", __func__);
 319
 320	tty_port_hangup(&port->port);
 321}
 322
 323static void serial_close(struct tty_struct *tty, struct file *filp)
 324{
 325	struct usb_serial_port *port = tty->driver_data;
 326
 327	dev_dbg(&port->dev, "%s\n", __func__);
 328
 329	tty_port_close(&port->port, tty, filp);
 330}
 331
 332/**
 333 * serial_cleanup - free resources post close/hangup
 334 * @tty: tty to clean up
 335 *
 336 * Do the resource freeing and refcount dropping for the port.
 337 * Avoid freeing the console.
 338 *
 339 * Called asynchronously after the last tty kref is dropped.
 340 */
 341static void serial_cleanup(struct tty_struct *tty)
 342{
 343	struct usb_serial_port *port = tty->driver_data;
 344	struct usb_serial *serial;
 345	struct module *owner;
 346
 347	dev_dbg(&port->dev, "%s\n", __func__);
 348
 349	/* The console is magical.  Do not hang up the console hardware
 350	 * or there will be tears.
 351	 */
 352	if (port->port.console)
 353		return;
 354
 355	tty->driver_data = NULL;
 356
 357	serial = port->serial;
 358	owner = serial->type->driver.owner;
 359
 360	usb_serial_put(serial);
 361	module_put(owner);
 362}
 363
 364static ssize_t serial_write(struct tty_struct *tty, const u8 *buf, size_t count)
 365{
 366	struct usb_serial_port *port = tty->driver_data;
 367	int retval = -ENODEV;
 368
 369	if (port->serial->dev->state == USB_STATE_NOTATTACHED)
 370		goto exit;
 371
 372	dev_dbg(&port->dev, "%s - %zu byte(s)\n", __func__, count);
 373
 374	retval = port->serial->type->write(tty, port, buf, count);
 375	if (retval < 0)
 376		retval = usb_translate_errors(retval);
 377exit:
 378	return retval;
 379}
 380
 381static unsigned int serial_write_room(struct tty_struct *tty)
 382{
 383	struct usb_serial_port *port = tty->driver_data;
 384
 385	dev_dbg(&port->dev, "%s\n", __func__);
 386
 387	return port->serial->type->write_room(tty);
 388}
 389
 390static unsigned int serial_chars_in_buffer(struct tty_struct *tty)
 391{
 392	struct usb_serial_port *port = tty->driver_data;
 393	struct usb_serial *serial = port->serial;
 394
 395	dev_dbg(&port->dev, "%s\n", __func__);
 396
 397	if (serial->disconnected)
 398		return 0;
 399
 400	return serial->type->chars_in_buffer(tty);
 401}
 402
 403static void serial_wait_until_sent(struct tty_struct *tty, int timeout)
 404{
 405	struct usb_serial_port *port = tty->driver_data;
 406	struct usb_serial *serial = port->serial;
 407
 408	dev_dbg(&port->dev, "%s\n", __func__);
 409
 410	if (!port->serial->type->wait_until_sent)
 411		return;
 412
 413	mutex_lock(&serial->disc_mutex);
 414	if (!serial->disconnected)
 415		port->serial->type->wait_until_sent(tty, timeout);
 416	mutex_unlock(&serial->disc_mutex);
 417}
 418
 419static void serial_throttle(struct tty_struct *tty)
 420{
 421	struct usb_serial_port *port = tty->driver_data;
 422
 423	dev_dbg(&port->dev, "%s\n", __func__);
 424
 425	if (port->serial->type->throttle)
 426		port->serial->type->throttle(tty);
 427}
 428
 429static void serial_unthrottle(struct tty_struct *tty)
 430{
 431	struct usb_serial_port *port = tty->driver_data;
 432
 433	dev_dbg(&port->dev, "%s\n", __func__);
 434
 435	if (port->serial->type->unthrottle)
 436		port->serial->type->unthrottle(tty);
 437}
 438
 439static int serial_get_serial(struct tty_struct *tty, struct serial_struct *ss)
 440{
 441	struct usb_serial_port *port = tty->driver_data;
 442	struct tty_port *tport = &port->port;
 443	unsigned int close_delay, closing_wait;
 444
 445	mutex_lock(&tport->mutex);
 446
 447	close_delay = jiffies_to_msecs(tport->close_delay) / 10;
 448	closing_wait = tport->closing_wait;
 449	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
 450		closing_wait = jiffies_to_msecs(closing_wait) / 10;
 451
 452	ss->line = port->minor;
 453	ss->close_delay = close_delay;
 454	ss->closing_wait = closing_wait;
 455
 456	if (port->serial->type->get_serial)
 457		port->serial->type->get_serial(tty, ss);
 458
 459	mutex_unlock(&tport->mutex);
 460
 461	return 0;
 462}
 463
 464static int serial_set_serial(struct tty_struct *tty, struct serial_struct *ss)
 465{
 466	struct usb_serial_port *port = tty->driver_data;
 467	struct tty_port *tport = &port->port;
 468	unsigned int close_delay, closing_wait;
 469	int ret = 0;
 470
 471	close_delay = msecs_to_jiffies(ss->close_delay * 10);
 472	closing_wait = ss->closing_wait;
 473	if (closing_wait != ASYNC_CLOSING_WAIT_NONE)
 474		closing_wait = msecs_to_jiffies(closing_wait * 10);
 475
 476	mutex_lock(&tport->mutex);
 477
 478	if (!capable(CAP_SYS_ADMIN)) {
 479		if (close_delay != tport->close_delay ||
 480				closing_wait != tport->closing_wait) {
 481			ret = -EPERM;
 482			goto out_unlock;
 483		}
 484	}
 485
 486	if (port->serial->type->set_serial) {
 487		ret = port->serial->type->set_serial(tty, ss);
 488		if (ret)
 489			goto out_unlock;
 490	}
 491
 492	tport->close_delay = close_delay;
 493	tport->closing_wait = closing_wait;
 494out_unlock:
 495	mutex_unlock(&tport->mutex);
 496
 497	return ret;
 498}
 499
 500static int serial_ioctl(struct tty_struct *tty,
 501					unsigned int cmd, unsigned long arg)
 502{
 503	struct usb_serial_port *port = tty->driver_data;
 504	int retval = -ENOIOCTLCMD;
 505
 506	dev_dbg(&port->dev, "%s - cmd 0x%04x\n", __func__, cmd);
 507
 508	switch (cmd) {
 509	case TIOCMIWAIT:
 510		if (port->serial->type->tiocmiwait)
 511			retval = port->serial->type->tiocmiwait(tty, arg);
 512		break;
 513	default:
 514		if (port->serial->type->ioctl)
 515			retval = port->serial->type->ioctl(tty, cmd, arg);
 516	}
 517
 518	return retval;
 519}
 520
 521static void serial_set_termios(struct tty_struct *tty,
 522		               const struct ktermios *old)
 523{
 524	struct usb_serial_port *port = tty->driver_data;
 525
 526	dev_dbg(&port->dev, "%s\n", __func__);
 527
 528	if (port->serial->type->set_termios)
 529		port->serial->type->set_termios(tty, port, old);
 530	else
 531		tty_termios_copy_hw(&tty->termios, old);
 532}
 533
 534static int serial_break(struct tty_struct *tty, int break_state)
 535{
 536	struct usb_serial_port *port = tty->driver_data;
 537
 538	dev_dbg(&port->dev, "%s\n", __func__);
 539
 540	if (port->serial->type->break_ctl)
 541		return port->serial->type->break_ctl(tty, break_state);
 542
 543	return -ENOTTY;
 544}
 545
 546static int serial_proc_show(struct seq_file *m, void *v)
 547{
 548	struct usb_serial *serial;
 549	struct usb_serial_port *port;
 550	int i;
 551	char tmp[40];
 552
 553	seq_puts(m, "usbserinfo:1.0 driver:2.0\n");
 554	for (i = 0; i < USB_SERIAL_TTY_MINORS; ++i) {
 555		port = usb_serial_port_get_by_minor(i);
 556		if (port == NULL)
 557			continue;
 558		serial = port->serial;
 559
 560		seq_printf(m, "%d:", i);
 561		if (serial->type->driver.owner)
 562			seq_printf(m, " module:%s",
 563				module_name(serial->type->driver.owner));
 564		seq_printf(m, " name:\"%s\"",
 565				serial->type->description);
 566		seq_printf(m, " vendor:%04x product:%04x",
 567			le16_to_cpu(serial->dev->descriptor.idVendor),
 568			le16_to_cpu(serial->dev->descriptor.idProduct));
 569		seq_printf(m, " num_ports:%d", serial->num_ports);
 570		seq_printf(m, " port:%d", port->port_number);
 571		usb_make_path(serial->dev, tmp, sizeof(tmp));
 572		seq_printf(m, " path:%s", tmp);
 573
 574		seq_putc(m, '\n');
 575		usb_serial_put(serial);
 576		mutex_unlock(&serial->disc_mutex);
 577	}
 578	return 0;
 579}
 580
 581static int serial_tiocmget(struct tty_struct *tty)
 582{
 583	struct usb_serial_port *port = tty->driver_data;
 584
 585	dev_dbg(&port->dev, "%s\n", __func__);
 586
 587	if (port->serial->type->tiocmget)
 588		return port->serial->type->tiocmget(tty);
 589	return -ENOTTY;
 590}
 591
 592static int serial_tiocmset(struct tty_struct *tty,
 593			    unsigned int set, unsigned int clear)
 594{
 595	struct usb_serial_port *port = tty->driver_data;
 596
 597	dev_dbg(&port->dev, "%s\n", __func__);
 598
 599	if (port->serial->type->tiocmset)
 600		return port->serial->type->tiocmset(tty, set, clear);
 601	return -ENOTTY;
 602}
 603
 604static int serial_get_icount(struct tty_struct *tty,
 605				struct serial_icounter_struct *icount)
 606{
 607	struct usb_serial_port *port = tty->driver_data;
 608
 609	dev_dbg(&port->dev, "%s\n", __func__);
 610
 611	if (port->serial->type->get_icount)
 612		return port->serial->type->get_icount(tty, icount);
 613	return -ENOTTY;
 614}
 615
 616/*
 617 * We would be calling tty_wakeup here, but unfortunately some line
 618 * disciplines have an annoying habit of calling tty->write from
 619 * the write wakeup callback (e.g. n_hdlc.c).
 620 */
 621void usb_serial_port_softint(struct usb_serial_port *port)
 622{
 623	schedule_work(&port->work);
 624}
 625EXPORT_SYMBOL_GPL(usb_serial_port_softint);
 626
 627static void usb_serial_port_work(struct work_struct *work)
 628{
 629	struct usb_serial_port *port =
 630		container_of(work, struct usb_serial_port, work);
 631
 632	tty_port_tty_wakeup(&port->port);
 633}
 634
 635static void usb_serial_port_poison_urbs(struct usb_serial_port *port)
 636{
 637	int i;
 638
 639	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 640		usb_poison_urb(port->read_urbs[i]);
 641	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 642		usb_poison_urb(port->write_urbs[i]);
 643
 644	usb_poison_urb(port->interrupt_in_urb);
 645	usb_poison_urb(port->interrupt_out_urb);
 646}
 647
 648static void usb_serial_port_unpoison_urbs(struct usb_serial_port *port)
 649{
 650	int i;
 651
 652	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
 653		usb_unpoison_urb(port->read_urbs[i]);
 654	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
 655		usb_unpoison_urb(port->write_urbs[i]);
 656
 657	usb_unpoison_urb(port->interrupt_in_urb);
 658	usb_unpoison_urb(port->interrupt_out_urb);
 659}
 660
 661static void usb_serial_port_release(struct device *dev)
 662{
 663	struct usb_serial_port *port = to_usb_serial_port(dev);
 664	int i;
 665
 666	dev_dbg(dev, "%s\n", __func__);
 667
 668	usb_free_urb(port->interrupt_in_urb);
 669	usb_free_urb(port->interrupt_out_urb);
 670	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 671		usb_free_urb(port->read_urbs[i]);
 672		kfree(port->bulk_in_buffers[i]);
 673	}
 674	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 675		usb_free_urb(port->write_urbs[i]);
 676		kfree(port->bulk_out_buffers[i]);
 677	}
 678	kfifo_free(&port->write_fifo);
 679	kfree(port->interrupt_in_buffer);
 680	kfree(port->interrupt_out_buffer);
 681	tty_port_destroy(&port->port);
 682	kfree(port);
 683}
 684
 685static struct usb_serial *create_serial(struct usb_device *dev,
 686					struct usb_interface *interface,
 687					struct usb_serial_driver *driver)
 688{
 689	struct usb_serial *serial;
 690
 691	serial = kzalloc(sizeof(*serial), GFP_KERNEL);
 692	if (!serial)
 693		return NULL;
 694	serial->dev = usb_get_dev(dev);
 695	serial->type = driver;
 696	serial->interface = usb_get_intf(interface);
 697	kref_init(&serial->kref);
 698	mutex_init(&serial->disc_mutex);
 699	serial->minors_reserved = 0;
 700
 701	return serial;
 702}
 703
 704static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
 705					    struct usb_serial_driver *drv)
 706{
 707	struct usb_dynid *dynid;
 708
 709	spin_lock(&drv->dynids.lock);
 710	list_for_each_entry(dynid, &drv->dynids.list, node) {
 711		if (usb_match_one_id(intf, &dynid->id)) {
 712			spin_unlock(&drv->dynids.lock);
 713			return &dynid->id;
 714		}
 715	}
 716	spin_unlock(&drv->dynids.lock);
 717	return NULL;
 718}
 719
 720static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
 721						struct usb_interface *intf)
 722{
 723	const struct usb_device_id *id;
 724
 725	id = usb_match_id(intf, drv->id_table);
 726	if (id) {
 727		dev_dbg(&intf->dev, "static descriptor matches\n");
 728		goto exit;
 729	}
 730	id = match_dynamic_id(intf, drv);
 731	if (id)
 732		dev_dbg(&intf->dev, "dynamic descriptor matches\n");
 733exit:
 734	return id;
 735}
 736
 737/* Caller must hold table_lock */
 738static struct usb_serial_driver *search_serial_device(
 739					struct usb_interface *iface)
 740{
 741	const struct usb_device_id *id = NULL;
 742	struct usb_serial_driver *drv;
 743	struct usb_driver *driver = to_usb_driver(iface->dev.driver);
 744
 745	/* Check if the usb id matches a known device */
 746	list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
 747		if (drv->usb_driver == driver)
 748			id = get_iface_id(drv, iface);
 749		if (id)
 750			return drv;
 751	}
 752
 753	return NULL;
 754}
 755
 756static bool serial_port_carrier_raised(struct tty_port *port)
 757{
 758	struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 759	struct usb_serial_driver *drv = p->serial->type;
 760
 761	if (drv->carrier_raised)
 762		return drv->carrier_raised(p);
 763	/* No carrier control - don't block */
 764	return true;
 765}
 766
 767static void serial_port_dtr_rts(struct tty_port *port, bool on)
 768{
 769	struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
 770	struct usb_serial_driver *drv = p->serial->type;
 771
 772	if (drv->dtr_rts)
 773		drv->dtr_rts(p, on);
 774}
 775
 776static ssize_t port_number_show(struct device *dev,
 777				struct device_attribute *attr, char *buf)
 778{
 779	struct usb_serial_port *port = to_usb_serial_port(dev);
 780
 781	return sprintf(buf, "%u\n", port->port_number);
 782}
 783static DEVICE_ATTR_RO(port_number);
 784
 785static struct attribute *usb_serial_port_attrs[] = {
 786	&dev_attr_port_number.attr,
 787	NULL
 788};
 789ATTRIBUTE_GROUPS(usb_serial_port);
 790
 791static const struct tty_port_operations serial_port_ops = {
 792	.carrier_raised		= serial_port_carrier_raised,
 793	.dtr_rts		= serial_port_dtr_rts,
 794	.activate		= serial_port_activate,
 795	.shutdown		= serial_port_shutdown,
 796};
 797
 798static void store_endpoint(struct usb_serial *serial,
 799					struct usb_serial_endpoints *epds,
 800					struct usb_endpoint_descriptor *epd)
 801{
 802	struct device *dev = &serial->interface->dev;
 803	u8 addr = epd->bEndpointAddress;
 804
 805	if (usb_endpoint_is_bulk_in(epd)) {
 806		if (epds->num_bulk_in == ARRAY_SIZE(epds->bulk_in))
 807			return;
 808		dev_dbg(dev, "found bulk in endpoint %02x\n", addr);
 809		epds->bulk_in[epds->num_bulk_in++] = epd;
 810	} else if (usb_endpoint_is_bulk_out(epd)) {
 811		if (epds->num_bulk_out == ARRAY_SIZE(epds->bulk_out))
 812			return;
 813		dev_dbg(dev, "found bulk out endpoint %02x\n", addr);
 814		epds->bulk_out[epds->num_bulk_out++] = epd;
 815	} else if (usb_endpoint_is_int_in(epd)) {
 816		if (epds->num_interrupt_in == ARRAY_SIZE(epds->interrupt_in))
 817			return;
 818		dev_dbg(dev, "found interrupt in endpoint %02x\n", addr);
 819		epds->interrupt_in[epds->num_interrupt_in++] = epd;
 820	} else if (usb_endpoint_is_int_out(epd)) {
 821		if (epds->num_interrupt_out == ARRAY_SIZE(epds->interrupt_out))
 822			return;
 823		dev_dbg(dev, "found interrupt out endpoint %02x\n", addr);
 824		epds->interrupt_out[epds->num_interrupt_out++] = epd;
 825	}
 826}
 827
 828static void find_endpoints(struct usb_serial *serial,
 829					struct usb_serial_endpoints *epds,
 830					struct usb_interface *intf)
 831{
 832	struct usb_host_interface *iface_desc;
 833	struct usb_endpoint_descriptor *epd;
 834	unsigned int i;
 835
 836	iface_desc = intf->cur_altsetting;
 837	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 838		epd = &iface_desc->endpoint[i].desc;
 839		store_endpoint(serial, epds, epd);
 840	}
 841}
 842
 843static int setup_port_bulk_in(struct usb_serial_port *port,
 844					struct usb_endpoint_descriptor *epd)
 845{
 846	struct usb_serial_driver *type = port->serial->type;
 847	struct usb_device *udev = port->serial->dev;
 848	int buffer_size;
 849	int i;
 850
 851	buffer_size = max_t(int, type->bulk_in_size, usb_endpoint_maxp(epd));
 852	port->bulk_in_size = buffer_size;
 853	port->bulk_in_endpointAddress = epd->bEndpointAddress;
 854
 855	for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
 856		set_bit(i, &port->read_urbs_free);
 857		port->read_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
 858		if (!port->read_urbs[i])
 859			return -ENOMEM;
 860		port->bulk_in_buffers[i] = kmalloc(buffer_size, GFP_KERNEL);
 861		if (!port->bulk_in_buffers[i])
 862			return -ENOMEM;
 863		usb_fill_bulk_urb(port->read_urbs[i], udev,
 864				usb_rcvbulkpipe(udev, epd->bEndpointAddress),
 865				port->bulk_in_buffers[i], buffer_size,
 866				type->read_bulk_callback, port);
 867	}
 868
 869	port->read_urb = port->read_urbs[0];
 870	port->bulk_in_buffer = port->bulk_in_buffers[0];
 871
 872	return 0;
 873}
 874
 875static int setup_port_bulk_out(struct usb_serial_port *port,
 876					struct usb_endpoint_descriptor *epd)
 877{
 878	struct usb_serial_driver *type = port->serial->type;
 879	struct usb_device *udev = port->serial->dev;
 880	int buffer_size;
 881	int i;
 882
 883	if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
 884		return -ENOMEM;
 885	if (type->bulk_out_size)
 886		buffer_size = type->bulk_out_size;
 887	else
 888		buffer_size = usb_endpoint_maxp(epd);
 889	port->bulk_out_size = buffer_size;
 890	port->bulk_out_endpointAddress = epd->bEndpointAddress;
 891
 892	for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
 893		set_bit(i, &port->write_urbs_free);
 894		port->write_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
 895		if (!port->write_urbs[i])
 896			return -ENOMEM;
 897		port->bulk_out_buffers[i] = kmalloc(buffer_size, GFP_KERNEL);
 898		if (!port->bulk_out_buffers[i])
 899			return -ENOMEM;
 900		usb_fill_bulk_urb(port->write_urbs[i], udev,
 901				usb_sndbulkpipe(udev, epd->bEndpointAddress),
 902				port->bulk_out_buffers[i], buffer_size,
 903				type->write_bulk_callback, port);
 904	}
 905
 906	port->write_urb = port->write_urbs[0];
 907	port->bulk_out_buffer = port->bulk_out_buffers[0];
 908
 909	return 0;
 910}
 911
 912static int setup_port_interrupt_in(struct usb_serial_port *port,
 913					struct usb_endpoint_descriptor *epd)
 914{
 915	struct usb_serial_driver *type = port->serial->type;
 916	struct usb_device *udev = port->serial->dev;
 917	int buffer_size;
 918
 919	port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
 920	if (!port->interrupt_in_urb)
 921		return -ENOMEM;
 922	buffer_size = usb_endpoint_maxp(epd);
 923	port->interrupt_in_endpointAddress = epd->bEndpointAddress;
 924	port->interrupt_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
 925	if (!port->interrupt_in_buffer)
 926		return -ENOMEM;
 927	usb_fill_int_urb(port->interrupt_in_urb, udev,
 928			usb_rcvintpipe(udev, epd->bEndpointAddress),
 929			port->interrupt_in_buffer, buffer_size,
 930			type->read_int_callback, port,
 931			epd->bInterval);
 932
 933	return 0;
 934}
 935
 936static int setup_port_interrupt_out(struct usb_serial_port *port,
 937					struct usb_endpoint_descriptor *epd)
 938{
 939	struct usb_serial_driver *type = port->serial->type;
 940	struct usb_device *udev = port->serial->dev;
 941	int buffer_size;
 942
 943	port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
 944	if (!port->interrupt_out_urb)
 945		return -ENOMEM;
 946	buffer_size = usb_endpoint_maxp(epd);
 947	port->interrupt_out_size = buffer_size;
 948	port->interrupt_out_endpointAddress = epd->bEndpointAddress;
 949	port->interrupt_out_buffer = kmalloc(buffer_size, GFP_KERNEL);
 950	if (!port->interrupt_out_buffer)
 951		return -ENOMEM;
 952	usb_fill_int_urb(port->interrupt_out_urb, udev,
 953			usb_sndintpipe(udev, epd->bEndpointAddress),
 954			port->interrupt_out_buffer, buffer_size,
 955			type->write_int_callback, port,
 956			epd->bInterval);
 957
 958	return 0;
 959}
 960
 961static int usb_serial_probe(struct usb_interface *interface,
 962			       const struct usb_device_id *id)
 963{
 964	struct device *ddev = &interface->dev;
 965	struct usb_device *dev = interface_to_usbdev(interface);
 966	struct usb_serial *serial = NULL;
 967	struct usb_serial_port *port;
 968	struct usb_serial_endpoints *epds;
 969	struct usb_serial_driver *type = NULL;
 970	int retval;
 971	int i;
 972	int num_ports = 0;
 973	unsigned char max_endpoints;
 974
 975	mutex_lock(&table_lock);
 976	type = search_serial_device(interface);
 977	if (!type) {
 978		mutex_unlock(&table_lock);
 979		dev_dbg(ddev, "none matched\n");
 980		return -ENODEV;
 981	}
 982
 983	if (!try_module_get(type->driver.owner)) {
 984		mutex_unlock(&table_lock);
 985		dev_err(ddev, "module get failed, exiting\n");
 986		return -EIO;
 987	}
 988	mutex_unlock(&table_lock);
 989
 990	serial = create_serial(dev, interface, type);
 991	if (!serial) {
 992		retval = -ENOMEM;
 993		goto err_put_module;
 994	}
 995
 996	/* if this device type has a probe function, call it */
 997	if (type->probe) {
 998		const struct usb_device_id *id;
 999
1000		id = get_iface_id(type, interface);
1001		retval = type->probe(serial, id);
1002
1003		if (retval) {
1004			dev_dbg(ddev, "sub driver rejected device\n");
1005			goto err_release_sibling;
1006		}
1007	}
1008
1009	/* descriptor matches, let's find the endpoints needed */
1010	epds = kzalloc(sizeof(*epds), GFP_KERNEL);
1011	if (!epds) {
1012		retval = -ENOMEM;
1013		goto err_release_sibling;
1014	}
1015
1016	find_endpoints(serial, epds, interface);
1017	if (serial->sibling)
1018		find_endpoints(serial, epds, serial->sibling);
1019
1020	if (epds->num_bulk_in < type->num_bulk_in ||
1021			epds->num_bulk_out < type->num_bulk_out ||
1022			epds->num_interrupt_in < type->num_interrupt_in ||
1023			epds->num_interrupt_out < type->num_interrupt_out) {
1024		dev_err(ddev, "required endpoints missing\n");
1025		retval = -ENODEV;
1026		goto err_free_epds;
1027	}
1028
1029	if (type->calc_num_ports) {
1030		retval = type->calc_num_ports(serial, epds);
1031		if (retval < 0)
1032			goto err_free_epds;
1033		num_ports = retval;
1034	}
1035
1036	if (!num_ports)
1037		num_ports = type->num_ports;
1038
1039	if (num_ports > MAX_NUM_PORTS) {
1040		dev_warn(ddev, "too many ports requested: %d\n", num_ports);
1041		num_ports = MAX_NUM_PORTS;
1042	}
1043
1044	serial->num_ports = (unsigned char)num_ports;
1045	serial->num_bulk_in = epds->num_bulk_in;
1046	serial->num_bulk_out = epds->num_bulk_out;
1047	serial->num_interrupt_in = epds->num_interrupt_in;
1048	serial->num_interrupt_out = epds->num_interrupt_out;
1049
1050	/* found all that we need */
1051	dev_info(ddev, "%s converter detected\n", type->description);
1052
1053	/* create our ports, we need as many as the max endpoints */
1054	/* we don't use num_ports here because some devices have more
1055	   endpoint pairs than ports */
1056	max_endpoints = max(epds->num_bulk_in, epds->num_bulk_out);
1057	max_endpoints = max(max_endpoints, epds->num_interrupt_in);
1058	max_endpoints = max(max_endpoints, epds->num_interrupt_out);
1059	max_endpoints = max(max_endpoints, serial->num_ports);
1060	serial->num_port_pointers = max_endpoints;
1061
1062	dev_dbg(ddev, "setting up %d port structure(s)\n", max_endpoints);
1063	for (i = 0; i < max_endpoints; ++i) {
1064		port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
1065		if (!port) {
1066			retval = -ENOMEM;
1067			goto err_free_epds;
1068		}
1069		tty_port_init(&port->port);
1070		port->port.ops = &serial_port_ops;
1071		port->serial = serial;
1072		spin_lock_init(&port->lock);
1073		/* Keep this for private driver use for the moment but
1074		   should probably go away */
1075		INIT_WORK(&port->work, usb_serial_port_work);
1076		serial->port[i] = port;
1077		port->dev.parent = &interface->dev;
1078		port->dev.driver = NULL;
1079		port->dev.bus = &usb_serial_bus_type;
1080		port->dev.release = &usb_serial_port_release;
1081		port->dev.groups = usb_serial_port_groups;
1082		device_initialize(&port->dev);
1083	}
1084
1085	/* set up the endpoint information */
1086	for (i = 0; i < epds->num_bulk_in; ++i) {
1087		retval = setup_port_bulk_in(serial->port[i], epds->bulk_in[i]);
1088		if (retval)
1089			goto err_free_epds;
1090	}
1091
1092	for (i = 0; i < epds->num_bulk_out; ++i) {
1093		retval = setup_port_bulk_out(serial->port[i],
1094				epds->bulk_out[i]);
1095		if (retval)
1096			goto err_free_epds;
1097	}
1098
1099	if (serial->type->read_int_callback) {
1100		for (i = 0; i < epds->num_interrupt_in; ++i) {
1101			retval = setup_port_interrupt_in(serial->port[i],
1102					epds->interrupt_in[i]);
1103			if (retval)
1104				goto err_free_epds;
1105		}
1106	} else if (epds->num_interrupt_in) {
1107		dev_dbg(ddev, "The device claims to support interrupt in transfers, but read_int_callback is not defined\n");
1108	}
1109
1110	if (serial->type->write_int_callback) {
1111		for (i = 0; i < epds->num_interrupt_out; ++i) {
1112			retval = setup_port_interrupt_out(serial->port[i],
1113					epds->interrupt_out[i]);
1114			if (retval)
1115				goto err_free_epds;
1116		}
1117	} else if (epds->num_interrupt_out) {
1118		dev_dbg(ddev, "The device claims to support interrupt out transfers, but write_int_callback is not defined\n");
1119	}
1120
1121	usb_set_intfdata(interface, serial);
1122
1123	/* if this device type has an attach function, call it */
1124	if (type->attach) {
1125		retval = type->attach(serial);
1126		if (retval < 0)
1127			goto err_free_epds;
1128		serial->attached = 1;
1129		if (retval > 0) {
1130			/* quietly accept this device, but don't bind to a
1131			   serial port as it's about to disappear */
1132			serial->num_ports = 0;
1133			goto exit;
1134		}
1135	} else {
1136		serial->attached = 1;
1137	}
1138
1139	retval = allocate_minors(serial, num_ports);
1140	if (retval) {
1141		dev_err(ddev, "No more free serial minor numbers\n");
1142		goto err_free_epds;
1143	}
1144
1145	/* register all of the individual ports with the driver core */
1146	for (i = 0; i < num_ports; ++i) {
1147		port = serial->port[i];
1148		dev_set_name(&port->dev, "ttyUSB%d", port->minor);
1149		dev_dbg(ddev, "registering %s\n", dev_name(&port->dev));
1150		device_enable_async_suspend(&port->dev);
1151
1152		retval = device_add(&port->dev);
1153		if (retval)
1154			dev_err(ddev, "Error registering port device, continuing\n");
1155	}
1156
1157	if (num_ports > 0)
1158		usb_serial_console_init(serial->port[0]->minor);
1159exit:
1160	kfree(epds);
1161	module_put(type->driver.owner);
1162	return 0;
1163
1164err_free_epds:
1165	kfree(epds);
1166err_release_sibling:
1167	release_sibling(serial, interface);
1168	usb_serial_put(serial);
1169err_put_module:
1170	module_put(type->driver.owner);
1171
1172	return retval;
1173}
1174
1175static void usb_serial_disconnect(struct usb_interface *interface)
1176{
1177	int i;
1178	struct usb_serial *serial = usb_get_intfdata(interface);
1179	struct device *dev = &interface->dev;
1180	struct usb_serial_port *port;
1181	struct tty_struct *tty;
1182
1183	/* sibling interface is cleaning up */
1184	if (!serial)
1185		return;
1186
1187	usb_serial_console_disconnect(serial);
1188
1189	mutex_lock(&serial->disc_mutex);
1190	/* must set a flag, to signal subdrivers */
1191	serial->disconnected = 1;
1192	mutex_unlock(&serial->disc_mutex);
1193
1194	for (i = 0; i < serial->num_ports; ++i) {
1195		port = serial->port[i];
1196		tty = tty_port_tty_get(&port->port);
1197		if (tty) {
1198			tty_vhangup(tty);
1199			tty_kref_put(tty);
1200		}
1201		usb_serial_port_poison_urbs(port);
1202		wake_up_interruptible(&port->port.delta_msr_wait);
1203		cancel_work_sync(&port->work);
1204		if (device_is_registered(&port->dev))
1205			device_del(&port->dev);
1206	}
1207	if (serial->type->disconnect)
1208		serial->type->disconnect(serial);
1209
1210	release_sibling(serial, interface);
1211
1212	/* let the last holder of this object cause it to be cleaned up */
1213	usb_serial_put(serial);
1214	dev_info(dev, "device disconnected\n");
1215}
1216
1217int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1218{
1219	struct usb_serial *serial = usb_get_intfdata(intf);
1220	int i, r;
1221
1222	/* suspend when called for first sibling interface */
1223	if (serial->suspend_count++)
1224		return 0;
1225
1226	/*
1227	 * serial->type->suspend() MUST return 0 in system sleep context,
1228	 * otherwise, the resume callback has to recover device from
1229	 * previous suspend failure.
1230	 */
1231	if (serial->type->suspend) {
1232		r = serial->type->suspend(serial, message);
1233		if (r < 0) {
1234			serial->suspend_count--;
1235			return r;
1236		}
1237	}
1238
1239	for (i = 0; i < serial->num_ports; ++i)
1240		usb_serial_port_poison_urbs(serial->port[i]);
1241
1242	return 0;
1243}
1244EXPORT_SYMBOL(usb_serial_suspend);
1245
1246static void usb_serial_unpoison_port_urbs(struct usb_serial *serial)
1247{
1248	int i;
1249
1250	for (i = 0; i < serial->num_ports; ++i)
1251		usb_serial_port_unpoison_urbs(serial->port[i]);
1252}
1253
1254int usb_serial_resume(struct usb_interface *intf)
1255{
1256	struct usb_serial *serial = usb_get_intfdata(intf);
1257	int rv;
1258
1259	/* resume when called for last sibling interface */
1260	if (--serial->suspend_count)
1261		return 0;
1262
1263	usb_serial_unpoison_port_urbs(serial);
1264
1265	if (serial->type->resume)
1266		rv = serial->type->resume(serial);
1267	else
1268		rv = usb_serial_generic_resume(serial);
1269
1270	return rv;
1271}
1272EXPORT_SYMBOL(usb_serial_resume);
1273
1274static int usb_serial_reset_resume(struct usb_interface *intf)
1275{
1276	struct usb_serial *serial = usb_get_intfdata(intf);
1277	int rv;
1278
1279	/* resume when called for last sibling interface */
1280	if (--serial->suspend_count)
1281		return 0;
1282
1283	usb_serial_unpoison_port_urbs(serial);
1284
1285	if (serial->type->reset_resume) {
1286		rv = serial->type->reset_resume(serial);
1287	} else {
1288		rv = -EOPNOTSUPP;
1289		intf->needs_binding = 1;
1290	}
1291
1292	return rv;
1293}
1294
1295static const struct tty_operations serial_ops = {
1296	.open =			serial_open,
1297	.close =		serial_close,
1298	.write =		serial_write,
1299	.hangup =		serial_hangup,
1300	.write_room =		serial_write_room,
1301	.ioctl =		serial_ioctl,
1302	.set_termios =		serial_set_termios,
1303	.throttle =		serial_throttle,
1304	.unthrottle =		serial_unthrottle,
1305	.break_ctl =		serial_break,
1306	.chars_in_buffer =	serial_chars_in_buffer,
1307	.wait_until_sent =	serial_wait_until_sent,
1308	.tiocmget =		serial_tiocmget,
1309	.tiocmset =		serial_tiocmset,
1310	.get_icount =		serial_get_icount,
1311	.set_serial =		serial_set_serial,
1312	.get_serial =		serial_get_serial,
1313	.cleanup =		serial_cleanup,
1314	.install =		serial_install,
1315	.proc_show =		serial_proc_show,
1316};
1317
1318
1319struct tty_driver *usb_serial_tty_driver;
1320
1321static int __init usb_serial_init(void)
1322{
1323	int result;
1324
1325	usb_serial_tty_driver = tty_alloc_driver(USB_SERIAL_TTY_MINORS,
1326			TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV);
1327	if (IS_ERR(usb_serial_tty_driver))
1328		return PTR_ERR(usb_serial_tty_driver);
1329
1330	/* Initialize our global data */
1331	result = bus_register(&usb_serial_bus_type);
1332	if (result) {
1333		pr_err("%s - registering bus driver failed\n", __func__);
1334		goto err_put_driver;
1335	}
1336
1337	usb_serial_tty_driver->driver_name = "usbserial";
1338	usb_serial_tty_driver->name = "ttyUSB";
1339	usb_serial_tty_driver->major = USB_SERIAL_TTY_MAJOR;
1340	usb_serial_tty_driver->minor_start = 0;
1341	usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1342	usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1343	usb_serial_tty_driver->init_termios = tty_std_termios;
1344	usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1345							| HUPCL | CLOCAL;
1346	usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1347	usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1348	tty_set_operations(usb_serial_tty_driver, &serial_ops);
1349	result = tty_register_driver(usb_serial_tty_driver);
1350	if (result) {
1351		pr_err("%s - tty_register_driver failed\n", __func__);
1352		goto err_unregister_bus;
1353	}
1354
1355	/* register the generic driver, if we should */
1356	result = usb_serial_generic_register();
1357	if (result < 0) {
1358		pr_err("%s - registering generic driver failed\n", __func__);
1359		goto err_unregister_driver;
1360	}
1361
1362	return result;
1363
1364err_unregister_driver:
1365	tty_unregister_driver(usb_serial_tty_driver);
1366err_unregister_bus:
1367	bus_unregister(&usb_serial_bus_type);
1368err_put_driver:
1369	pr_err("%s - returning with error %d\n", __func__, result);
1370	tty_driver_kref_put(usb_serial_tty_driver);
1371	return result;
1372}
1373
1374
1375static void __exit usb_serial_exit(void)
1376{
1377	usb_serial_console_exit();
1378
1379	usb_serial_generic_deregister();
1380
1381	tty_unregister_driver(usb_serial_tty_driver);
1382	tty_driver_kref_put(usb_serial_tty_driver);
1383	bus_unregister(&usb_serial_bus_type);
1384	idr_destroy(&serial_minors);
1385}
1386
1387
1388module_init(usb_serial_init);
1389module_exit(usb_serial_exit);
1390
1391#define set_to_generic_if_null(type, function)				\
1392	do {								\
1393		if (!type->function) {					\
1394			type->function = usb_serial_generic_##function;	\
1395			pr_debug("%s: using generic " #function	"\n",	\
1396						type->driver.name);	\
1397		}							\
1398	} while (0)
1399
1400static void usb_serial_operations_init(struct usb_serial_driver *device)
1401{
1402	set_to_generic_if_null(device, open);
1403	set_to_generic_if_null(device, write);
1404	set_to_generic_if_null(device, close);
1405	set_to_generic_if_null(device, write_room);
1406	set_to_generic_if_null(device, chars_in_buffer);
1407	if (device->tx_empty)
1408		set_to_generic_if_null(device, wait_until_sent);
1409	set_to_generic_if_null(device, read_bulk_callback);
1410	set_to_generic_if_null(device, write_bulk_callback);
1411	set_to_generic_if_null(device, process_read_urb);
1412	set_to_generic_if_null(device, prepare_write_buffer);
1413}
1414
1415static int usb_serial_register(struct usb_serial_driver *driver)
1416{
1417	int retval;
1418
1419	if (usb_disabled())
1420		return -ENODEV;
1421
1422	if (!driver->description)
1423		driver->description = driver->driver.name;
1424	if (!driver->usb_driver) {
1425		WARN(1, "Serial driver %s has no usb_driver\n",
1426				driver->description);
1427		return -EINVAL;
1428	}
1429
1430	/* Prevent individual ports from being unbound. */
1431	driver->driver.suppress_bind_attrs = true;
1432
1433	usb_serial_operations_init(driver);
1434
1435	/* Add this device to our list of devices */
1436	mutex_lock(&table_lock);
1437	list_add(&driver->driver_list, &usb_serial_driver_list);
1438
1439	retval = usb_serial_bus_register(driver);
1440	if (retval) {
1441		pr_err("problem %d when registering driver %s\n", retval, driver->description);
1442		list_del(&driver->driver_list);
1443	} else {
1444		pr_info("USB Serial support registered for %s\n", driver->description);
1445	}
1446	mutex_unlock(&table_lock);
1447	return retval;
1448}
1449
1450static void usb_serial_deregister(struct usb_serial_driver *device)
1451{
1452	pr_info("USB Serial deregistering driver %s\n", device->description);
1453
1454	mutex_lock(&table_lock);
1455	list_del(&device->driver_list);
1456	mutex_unlock(&table_lock);
1457
1458	usb_serial_bus_deregister(device);
1459}
1460
1461/**
1462 * usb_serial_register_drivers - register drivers for a usb-serial module
1463 * @serial_drivers: NULL-terminated array of pointers to drivers to be registered
 
1464 * @name: name of the usb_driver for this set of @serial_drivers
1465 * @id_table: list of all devices this @serial_drivers set binds to
1466 *
1467 * Registers all the drivers in the @serial_drivers array, and dynamically
1468 * creates a struct usb_driver with the name @name and id_table of @id_table.
1469 */
1470int usb_serial_register_drivers(struct usb_serial_driver *const serial_drivers[],
1471				const char *name,
1472				const struct usb_device_id *id_table)
1473{
1474	int rc;
1475	struct usb_driver *udriver;
1476	struct usb_serial_driver * const *sd;
1477
1478	/*
1479	 * udriver must be registered before any of the serial drivers,
1480	 * because the store_new_id() routine for the serial drivers (in
1481	 * bus.c) probes udriver.
1482	 *
1483	 * Performance hack: We don't want udriver to be probed until
1484	 * the serial drivers are registered, because the probe would
1485	 * simply fail for lack of a matching serial driver.
1486	 * So we leave udriver's id_table set to NULL until we are all set.
1487	 *
1488	 * Suspend/resume support is implemented in the usb-serial core,
1489	 * so fill in the PM-related fields in udriver.
1490	 */
1491	udriver = kzalloc(sizeof(*udriver), GFP_KERNEL);
1492	if (!udriver)
1493		return -ENOMEM;
1494
1495	udriver->name = name;
1496	udriver->no_dynamic_id = 1;
1497	udriver->supports_autosuspend = 1;
1498	udriver->suspend = usb_serial_suspend;
1499	udriver->resume = usb_serial_resume;
1500	udriver->probe = usb_serial_probe;
1501	udriver->disconnect = usb_serial_disconnect;
1502
1503	/* we only set the reset_resume field if the serial_driver has one */
1504	for (sd = serial_drivers; *sd; ++sd) {
1505		if ((*sd)->reset_resume) {
1506			udriver->reset_resume = usb_serial_reset_resume;
1507			break;
1508		}
1509	}
1510
1511	rc = usb_register(udriver);
1512	if (rc)
1513		goto err_free_driver;
1514
1515	for (sd = serial_drivers; *sd; ++sd) {
1516		(*sd)->usb_driver = udriver;
 
1517		rc = usb_serial_register(*sd);
1518		if (rc)
1519			goto err_deregister_drivers;
1520	}
1521
1522	/* Now set udriver's id_table and look for matches */
1523	udriver->id_table = id_table;
1524	rc = driver_attach(&udriver->driver);
1525	return 0;
1526
1527err_deregister_drivers:
1528	while (sd-- > serial_drivers)
1529		usb_serial_deregister(*sd);
1530	usb_deregister(udriver);
1531err_free_driver:
1532	kfree(udriver);
1533	return rc;
1534}
1535EXPORT_SYMBOL_GPL(usb_serial_register_drivers);
1536
1537/**
1538 * usb_serial_deregister_drivers - deregister drivers for a usb-serial module
1539 * @serial_drivers: NULL-terminated array of pointers to drivers to be deregistered
1540 *
1541 * Deregisters all the drivers in the @serial_drivers array and deregisters and
1542 * frees the struct usb_driver that was created by the call to
1543 * usb_serial_register_drivers().
1544 */
1545void usb_serial_deregister_drivers(struct usb_serial_driver *const serial_drivers[])
1546{
1547	struct usb_driver *udriver = (*serial_drivers)->usb_driver;
1548
1549	for (; *serial_drivers; ++serial_drivers)
1550		usb_serial_deregister(*serial_drivers);
1551	usb_deregister(udriver);
1552	kfree(udriver);
1553}
1554EXPORT_SYMBOL_GPL(usb_serial_deregister_drivers);
1555
1556MODULE_AUTHOR(DRIVER_AUTHOR);
1557MODULE_DESCRIPTION(DRIVER_DESC);
1558MODULE_LICENSE("GPL v2");