xref: /linux/drivers/usb/class/cdc-acm.c (revision 5fd54ace4721fc5ce2bb5aef6318fcf17f421460)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * cdc-acm.c
4  *
5  * Copyright (c) 1999 Armin Fuerst	<fuerst@in.tum.de>
6  * Copyright (c) 1999 Pavel Machek	<pavel@ucw.cz>
7  * Copyright (c) 1999 Johannes Erdfelt	<johannes@erdfelt.com>
8  * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
9  * Copyright (c) 2004 Oliver Neukum	<oliver@neukum.name>
10  * Copyright (c) 2005 David Kubicek	<dave@awk.cz>
11  * Copyright (c) 2011 Johan Hovold	<jhovold@gmail.com>
12  *
13  * USB Abstract Control Model driver for USB modems and ISDN adapters
14  *
15  * Sponsored by SuSE
16  *
17  * This program is free software; you can redistribute it and/or modify
18  * it under the terms of the GNU General Public License as published by
19  * the Free Software Foundation; either version 2 of the License, or
20  * (at your option) any later version.
21  *
22  * This program is distributed in the hope that it will be useful,
23  * but WITHOUT ANY WARRANTY; without even the implied warranty of
24  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
25  * GNU General Public License for more details.
26  *
27  * You should have received a copy of the GNU General Public License
28  * along with this program; if not, write to the Free Software
29  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
30  */
31 
32 #undef DEBUG
33 #undef VERBOSE_DEBUG
34 
35 #include <linux/kernel.h>
36 #include <linux/sched/signal.h>
37 #include <linux/errno.h>
38 #include <linux/init.h>
39 #include <linux/slab.h>
40 #include <linux/log2.h>
41 #include <linux/tty.h>
42 #include <linux/serial.h>
43 #include <linux/tty_driver.h>
44 #include <linux/tty_flip.h>
45 #include <linux/module.h>
46 #include <linux/mutex.h>
47 #include <linux/uaccess.h>
48 #include <linux/usb.h>
49 #include <linux/usb/cdc.h>
50 #include <asm/byteorder.h>
51 #include <asm/unaligned.h>
52 #include <linux/idr.h>
53 #include <linux/list.h>
54 
55 #include "cdc-acm.h"
56 
57 
58 #define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek, Johan Hovold"
59 #define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
60 
61 static struct usb_driver acm_driver;
62 static struct tty_driver *acm_tty_driver;
63 
64 static DEFINE_IDR(acm_minors);
65 static DEFINE_MUTEX(acm_minors_lock);
66 
67 static void acm_tty_set_termios(struct tty_struct *tty,
68 				struct ktermios *termios_old);
69 
70 /*
71  * acm_minors accessors
72  */
73 
74 /*
75  * Look up an ACM structure by minor. If found and not disconnected, increment
76  * its refcount and return it with its mutex held.
77  */
78 static struct acm *acm_get_by_minor(unsigned int minor)
79 {
80 	struct acm *acm;
81 
82 	mutex_lock(&acm_minors_lock);
83 	acm = idr_find(&acm_minors, minor);
84 	if (acm) {
85 		mutex_lock(&acm->mutex);
86 		if (acm->disconnected) {
87 			mutex_unlock(&acm->mutex);
88 			acm = NULL;
89 		} else {
90 			tty_port_get(&acm->port);
91 			mutex_unlock(&acm->mutex);
92 		}
93 	}
94 	mutex_unlock(&acm_minors_lock);
95 	return acm;
96 }
97 
98 /*
99  * Try to find an available minor number and if found, associate it with 'acm'.
100  */
101 static int acm_alloc_minor(struct acm *acm)
102 {
103 	int minor;
104 
105 	mutex_lock(&acm_minors_lock);
106 	minor = idr_alloc(&acm_minors, acm, 0, ACM_TTY_MINORS, GFP_KERNEL);
107 	mutex_unlock(&acm_minors_lock);
108 
109 	return minor;
110 }
111 
112 /* Release the minor number associated with 'acm'.  */
113 static void acm_release_minor(struct acm *acm)
114 {
115 	mutex_lock(&acm_minors_lock);
116 	idr_remove(&acm_minors, acm->minor);
117 	mutex_unlock(&acm_minors_lock);
118 }
119 
120 /*
121  * Functions for ACM control messages.
122  */
123 
124 static int acm_ctrl_msg(struct acm *acm, int request, int value,
125 							void *buf, int len)
126 {
127 	int retval;
128 
129 	retval = usb_autopm_get_interface(acm->control);
130 	if (retval)
131 		return retval;
132 
133 	retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
134 		request, USB_RT_ACM, value,
135 		acm->control->altsetting[0].desc.bInterfaceNumber,
136 		buf, len, 5000);
137 
138 	dev_dbg(&acm->control->dev,
139 		"%s - rq 0x%02x, val %#x, len %#x, result %d\n",
140 		__func__, request, value, len, retval);
141 
142 	usb_autopm_put_interface(acm->control);
143 
144 	return retval < 0 ? retval : 0;
145 }
146 
147 /* devices aren't required to support these requests.
148  * the cdc acm descriptor tells whether they do...
149  */
150 static inline int acm_set_control(struct acm *acm, int control)
151 {
152 	if (acm->quirks & QUIRK_CONTROL_LINE_STATE)
153 		return -EOPNOTSUPP;
154 
155 	return acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE,
156 			control, NULL, 0);
157 }
158 
159 #define acm_set_line(acm, line) \
160 	acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line))
161 #define acm_send_break(acm, ms) \
162 	acm_ctrl_msg(acm, USB_CDC_REQ_SEND_BREAK, ms, NULL, 0)
163 
164 static void acm_kill_urbs(struct acm *acm)
165 {
166 	int i;
167 
168 	usb_kill_urb(acm->ctrlurb);
169 	for (i = 0; i < ACM_NW; i++)
170 		usb_kill_urb(acm->wb[i].urb);
171 	for (i = 0; i < acm->rx_buflimit; i++)
172 		usb_kill_urb(acm->read_urbs[i]);
173 }
174 
175 /*
176  * Write buffer management.
177  * All of these assume proper locks taken by the caller.
178  */
179 
180 static int acm_wb_alloc(struct acm *acm)
181 {
182 	int i, wbn;
183 	struct acm_wb *wb;
184 
185 	wbn = 0;
186 	i = 0;
187 	for (;;) {
188 		wb = &acm->wb[wbn];
189 		if (!wb->use) {
190 			wb->use = 1;
191 			return wbn;
192 		}
193 		wbn = (wbn + 1) % ACM_NW;
194 		if (++i >= ACM_NW)
195 			return -1;
196 	}
197 }
198 
199 static int acm_wb_is_avail(struct acm *acm)
200 {
201 	int i, n;
202 	unsigned long flags;
203 
204 	n = ACM_NW;
205 	spin_lock_irqsave(&acm->write_lock, flags);
206 	for (i = 0; i < ACM_NW; i++)
207 		n -= acm->wb[i].use;
208 	spin_unlock_irqrestore(&acm->write_lock, flags);
209 	return n;
210 }
211 
212 /*
213  * Finish write. Caller must hold acm->write_lock
214  */
215 static void acm_write_done(struct acm *acm, struct acm_wb *wb)
216 {
217 	wb->use = 0;
218 	acm->transmitting--;
219 	usb_autopm_put_interface_async(acm->control);
220 }
221 
222 /*
223  * Poke write.
224  *
225  * the caller is responsible for locking
226  */
227 
228 static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
229 {
230 	int rc;
231 
232 	acm->transmitting++;
233 
234 	wb->urb->transfer_buffer = wb->buf;
235 	wb->urb->transfer_dma = wb->dmah;
236 	wb->urb->transfer_buffer_length = wb->len;
237 	wb->urb->dev = acm->dev;
238 
239 	rc = usb_submit_urb(wb->urb, GFP_ATOMIC);
240 	if (rc < 0) {
241 		dev_err(&acm->data->dev,
242 			"%s - usb_submit_urb(write bulk) failed: %d\n",
243 			__func__, rc);
244 		acm_write_done(acm, wb);
245 	}
246 	return rc;
247 }
248 
249 /*
250  * attributes exported through sysfs
251  */
252 static ssize_t show_caps
253 (struct device *dev, struct device_attribute *attr, char *buf)
254 {
255 	struct usb_interface *intf = to_usb_interface(dev);
256 	struct acm *acm = usb_get_intfdata(intf);
257 
258 	return sprintf(buf, "%d", acm->ctrl_caps);
259 }
260 static DEVICE_ATTR(bmCapabilities, S_IRUGO, show_caps, NULL);
261 
262 static ssize_t show_country_codes
263 (struct device *dev, struct device_attribute *attr, char *buf)
264 {
265 	struct usb_interface *intf = to_usb_interface(dev);
266 	struct acm *acm = usb_get_intfdata(intf);
267 
268 	memcpy(buf, acm->country_codes, acm->country_code_size);
269 	return acm->country_code_size;
270 }
271 
272 static DEVICE_ATTR(wCountryCodes, S_IRUGO, show_country_codes, NULL);
273 
274 static ssize_t show_country_rel_date
275 (struct device *dev, struct device_attribute *attr, char *buf)
276 {
277 	struct usb_interface *intf = to_usb_interface(dev);
278 	struct acm *acm = usb_get_intfdata(intf);
279 
280 	return sprintf(buf, "%d", acm->country_rel_date);
281 }
282 
283 static DEVICE_ATTR(iCountryCodeRelDate, S_IRUGO, show_country_rel_date, NULL);
284 /*
285  * Interrupt handlers for various ACM device responses
286  */
287 
288 static void acm_process_notification(struct acm *acm, unsigned char *buf)
289 {
290 	int newctrl;
291 	int difference;
292 	struct usb_cdc_notification *dr = (struct usb_cdc_notification *)buf;
293 	unsigned char *data = buf + sizeof(struct usb_cdc_notification);
294 
295 	switch (dr->bNotificationType) {
296 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
297 		dev_dbg(&acm->control->dev,
298 			"%s - network connection: %d\n", __func__, dr->wValue);
299 		break;
300 
301 	case USB_CDC_NOTIFY_SERIAL_STATE:
302 		if (le16_to_cpu(dr->wLength) != 2) {
303 			dev_dbg(&acm->control->dev,
304 				"%s - malformed serial state\n", __func__);
305 			break;
306 		}
307 
308 		newctrl = get_unaligned_le16(data);
309 		dev_dbg(&acm->control->dev,
310 			"%s - serial state: 0x%x\n", __func__, newctrl);
311 
312 		if (!acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
313 			dev_dbg(&acm->control->dev,
314 				"%s - calling hangup\n", __func__);
315 			tty_port_tty_hangup(&acm->port, false);
316 		}
317 
318 		difference = acm->ctrlin ^ newctrl;
319 		spin_lock(&acm->read_lock);
320 		acm->ctrlin = newctrl;
321 		acm->oldcount = acm->iocount;
322 
323 		if (difference & ACM_CTRL_DSR)
324 			acm->iocount.dsr++;
325 		if (difference & ACM_CTRL_BRK)
326 			acm->iocount.brk++;
327 		if (difference & ACM_CTRL_RI)
328 			acm->iocount.rng++;
329 		if (difference & ACM_CTRL_DCD)
330 			acm->iocount.dcd++;
331 		if (difference & ACM_CTRL_FRAMING)
332 			acm->iocount.frame++;
333 		if (difference & ACM_CTRL_PARITY)
334 			acm->iocount.parity++;
335 		if (difference & ACM_CTRL_OVERRUN)
336 			acm->iocount.overrun++;
337 		spin_unlock(&acm->read_lock);
338 
339 		if (difference)
340 			wake_up_all(&acm->wioctl);
341 
342 		break;
343 
344 	default:
345 		dev_dbg(&acm->control->dev,
346 			"%s - unknown notification %d received: index %d len %d\n",
347 			__func__,
348 			dr->bNotificationType, dr->wIndex, dr->wLength);
349 	}
350 }
351 
352 /* control interface reports status changes with "interrupt" transfers */
353 static void acm_ctrl_irq(struct urb *urb)
354 {
355 	struct acm *acm = urb->context;
356 	struct usb_cdc_notification *dr = urb->transfer_buffer;
357 	unsigned int current_size = urb->actual_length;
358 	unsigned int expected_size, copy_size, alloc_size;
359 	int retval;
360 	int status = urb->status;
361 
362 	switch (status) {
363 	case 0:
364 		/* success */
365 		break;
366 	case -ECONNRESET:
367 	case -ENOENT:
368 	case -ESHUTDOWN:
369 		/* this urb is terminated, clean up */
370 		acm->nb_index = 0;
371 		dev_dbg(&acm->control->dev,
372 			"%s - urb shutting down with status: %d\n",
373 			__func__, status);
374 		return;
375 	default:
376 		dev_dbg(&acm->control->dev,
377 			"%s - nonzero urb status received: %d\n",
378 			__func__, status);
379 		goto exit;
380 	}
381 
382 	usb_mark_last_busy(acm->dev);
383 
384 	if (acm->nb_index)
385 		dr = (struct usb_cdc_notification *)acm->notification_buffer;
386 
387 	/* size = notification-header + (optional) data */
388 	expected_size = sizeof(struct usb_cdc_notification) +
389 					le16_to_cpu(dr->wLength);
390 
391 	if (current_size < expected_size) {
392 		/* notification is transmitted fragmented, reassemble */
393 		if (acm->nb_size < expected_size) {
394 			if (acm->nb_size) {
395 				kfree(acm->notification_buffer);
396 				acm->nb_size = 0;
397 			}
398 			alloc_size = roundup_pow_of_two(expected_size);
399 			/*
400 			 * kmalloc ensures a valid notification_buffer after a
401 			 * use of kfree in case the previous allocation was too
402 			 * small. Final freeing is done on disconnect.
403 			 */
404 			acm->notification_buffer =
405 				kmalloc(alloc_size, GFP_ATOMIC);
406 			if (!acm->notification_buffer)
407 				goto exit;
408 			acm->nb_size = alloc_size;
409 		}
410 
411 		copy_size = min(current_size,
412 				expected_size - acm->nb_index);
413 
414 		memcpy(&acm->notification_buffer[acm->nb_index],
415 		       urb->transfer_buffer, copy_size);
416 		acm->nb_index += copy_size;
417 		current_size = acm->nb_index;
418 	}
419 
420 	if (current_size >= expected_size) {
421 		/* notification complete */
422 		acm_process_notification(acm, (unsigned char *)dr);
423 		acm->nb_index = 0;
424 	}
425 
426 exit:
427 	retval = usb_submit_urb(urb, GFP_ATOMIC);
428 	if (retval && retval != -EPERM)
429 		dev_err(&acm->control->dev,
430 			"%s - usb_submit_urb failed: %d\n", __func__, retval);
431 }
432 
433 static int acm_submit_read_urb(struct acm *acm, int index, gfp_t mem_flags)
434 {
435 	int res;
436 
437 	if (!test_and_clear_bit(index, &acm->read_urbs_free))
438 		return 0;
439 
440 	res = usb_submit_urb(acm->read_urbs[index], mem_flags);
441 	if (res) {
442 		if (res != -EPERM) {
443 			dev_err(&acm->data->dev,
444 				"urb %d failed submission with %d\n",
445 				index, res);
446 		}
447 		set_bit(index, &acm->read_urbs_free);
448 		return res;
449 	} else {
450 		dev_vdbg(&acm->data->dev, "submitted urb %d\n", index);
451 	}
452 
453 	return 0;
454 }
455 
456 static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
457 {
458 	int res;
459 	int i;
460 
461 	for (i = 0; i < acm->rx_buflimit; ++i) {
462 		res = acm_submit_read_urb(acm, i, mem_flags);
463 		if (res)
464 			return res;
465 	}
466 
467 	return 0;
468 }
469 
470 static void acm_process_read_urb(struct acm *acm, struct urb *urb)
471 {
472 	if (!urb->actual_length)
473 		return;
474 
475 	tty_insert_flip_string(&acm->port, urb->transfer_buffer,
476 			urb->actual_length);
477 	tty_flip_buffer_push(&acm->port);
478 }
479 
480 static void acm_read_bulk_callback(struct urb *urb)
481 {
482 	struct acm_rb *rb = urb->context;
483 	struct acm *acm = rb->instance;
484 	unsigned long flags;
485 	int status = urb->status;
486 
487 	dev_vdbg(&acm->data->dev, "got urb %d, len %d, status %d\n",
488 		rb->index, urb->actual_length, status);
489 
490 	set_bit(rb->index, &acm->read_urbs_free);
491 
492 	if (!acm->dev) {
493 		dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
494 		return;
495 	}
496 
497 	switch (status) {
498 	case 0:
499 		usb_mark_last_busy(acm->dev);
500 		acm_process_read_urb(acm, urb);
501 		break;
502 	case -EPIPE:
503 		set_bit(EVENT_RX_STALL, &acm->flags);
504 		schedule_work(&acm->work);
505 		return;
506 	case -ENOENT:
507 	case -ECONNRESET:
508 	case -ESHUTDOWN:
509 		dev_dbg(&acm->data->dev,
510 			"%s - urb shutting down with status: %d\n",
511 			__func__, status);
512 		return;
513 	default:
514 		dev_dbg(&acm->data->dev,
515 			"%s - nonzero urb status received: %d\n",
516 			__func__, status);
517 		break;
518 	}
519 
520 	/*
521 	 * Unthrottle may run on another CPU which needs to see events
522 	 * in the same order. Submission has an implict barrier
523 	 */
524 	smp_mb__before_atomic();
525 
526 	/* throttle device if requested by tty */
527 	spin_lock_irqsave(&acm->read_lock, flags);
528 	acm->throttled = acm->throttle_req;
529 	if (!acm->throttled) {
530 		spin_unlock_irqrestore(&acm->read_lock, flags);
531 		acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
532 	} else {
533 		spin_unlock_irqrestore(&acm->read_lock, flags);
534 	}
535 }
536 
537 /* data interface wrote those outgoing bytes */
538 static void acm_write_bulk(struct urb *urb)
539 {
540 	struct acm_wb *wb = urb->context;
541 	struct acm *acm = wb->instance;
542 	unsigned long flags;
543 	int status = urb->status;
544 
545 	if (status || (urb->actual_length != urb->transfer_buffer_length))
546 		dev_vdbg(&acm->data->dev, "wrote len %d/%d, status %d\n",
547 			urb->actual_length,
548 			urb->transfer_buffer_length,
549 			status);
550 
551 	spin_lock_irqsave(&acm->write_lock, flags);
552 	acm_write_done(acm, wb);
553 	spin_unlock_irqrestore(&acm->write_lock, flags);
554 	set_bit(EVENT_TTY_WAKEUP, &acm->flags);
555 	schedule_work(&acm->work);
556 }
557 
558 static void acm_softint(struct work_struct *work)
559 {
560 	int i;
561 	struct acm *acm = container_of(work, struct acm, work);
562 
563 	if (test_bit(EVENT_RX_STALL, &acm->flags)) {
564 		if (!(usb_autopm_get_interface(acm->data))) {
565 			for (i = 0; i < acm->rx_buflimit; i++)
566 				usb_kill_urb(acm->read_urbs[i]);
567 			usb_clear_halt(acm->dev, acm->in);
568 			acm_submit_read_urbs(acm, GFP_KERNEL);
569 			usb_autopm_put_interface(acm->data);
570 		}
571 		clear_bit(EVENT_RX_STALL, &acm->flags);
572 	}
573 
574 	if (test_bit(EVENT_TTY_WAKEUP, &acm->flags)) {
575 		tty_port_tty_wakeup(&acm->port);
576 		clear_bit(EVENT_TTY_WAKEUP, &acm->flags);
577 	}
578 }
579 
580 /*
581  * TTY handlers
582  */
583 
584 static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
585 {
586 	struct acm *acm;
587 	int retval;
588 
589 	acm = acm_get_by_minor(tty->index);
590 	if (!acm)
591 		return -ENODEV;
592 
593 	retval = tty_standard_install(driver, tty);
594 	if (retval)
595 		goto error_init_termios;
596 
597 	tty->driver_data = acm;
598 
599 	return 0;
600 
601 error_init_termios:
602 	tty_port_put(&acm->port);
603 	return retval;
604 }
605 
606 static int acm_tty_open(struct tty_struct *tty, struct file *filp)
607 {
608 	struct acm *acm = tty->driver_data;
609 
610 	return tty_port_open(&acm->port, tty, filp);
611 }
612 
613 static void acm_port_dtr_rts(struct tty_port *port, int raise)
614 {
615 	struct acm *acm = container_of(port, struct acm, port);
616 	int val;
617 	int res;
618 
619 	if (raise)
620 		val = ACM_CTRL_DTR | ACM_CTRL_RTS;
621 	else
622 		val = 0;
623 
624 	/* FIXME: add missing ctrlout locking throughout driver */
625 	acm->ctrlout = val;
626 
627 	res = acm_set_control(acm, val);
628 	if (res && (acm->ctrl_caps & USB_CDC_CAP_LINE))
629 		dev_err(&acm->control->dev, "failed to set dtr/rts\n");
630 }
631 
632 static int acm_port_activate(struct tty_port *port, struct tty_struct *tty)
633 {
634 	struct acm *acm = container_of(port, struct acm, port);
635 	int retval = -ENODEV;
636 	int i;
637 
638 	mutex_lock(&acm->mutex);
639 	if (acm->disconnected)
640 		goto disconnected;
641 
642 	retval = usb_autopm_get_interface(acm->control);
643 	if (retval)
644 		goto error_get_interface;
645 
646 	/*
647 	 * FIXME: Why do we need this? Allocating 64K of physically contiguous
648 	 * memory is really nasty...
649 	 */
650 	set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
651 	acm->control->needs_remote_wakeup = 1;
652 
653 	acm->ctrlurb->dev = acm->dev;
654 	retval = usb_submit_urb(acm->ctrlurb, GFP_KERNEL);
655 	if (retval) {
656 		dev_err(&acm->control->dev,
657 			"%s - usb_submit_urb(ctrl irq) failed\n", __func__);
658 		goto error_submit_urb;
659 	}
660 
661 	acm_tty_set_termios(tty, NULL);
662 
663 	/*
664 	 * Unthrottle device in case the TTY was closed while throttled.
665 	 */
666 	spin_lock_irq(&acm->read_lock);
667 	acm->throttled = 0;
668 	acm->throttle_req = 0;
669 	spin_unlock_irq(&acm->read_lock);
670 
671 	retval = acm_submit_read_urbs(acm, GFP_KERNEL);
672 	if (retval)
673 		goto error_submit_read_urbs;
674 
675 	usb_autopm_put_interface(acm->control);
676 
677 	mutex_unlock(&acm->mutex);
678 
679 	return 0;
680 
681 error_submit_read_urbs:
682 	for (i = 0; i < acm->rx_buflimit; i++)
683 		usb_kill_urb(acm->read_urbs[i]);
684 	usb_kill_urb(acm->ctrlurb);
685 error_submit_urb:
686 	usb_autopm_put_interface(acm->control);
687 error_get_interface:
688 disconnected:
689 	mutex_unlock(&acm->mutex);
690 
691 	return usb_translate_errors(retval);
692 }
693 
694 static void acm_port_destruct(struct tty_port *port)
695 {
696 	struct acm *acm = container_of(port, struct acm, port);
697 
698 	acm_release_minor(acm);
699 	usb_put_intf(acm->control);
700 	kfree(acm->country_codes);
701 	kfree(acm);
702 }
703 
704 static void acm_port_shutdown(struct tty_port *port)
705 {
706 	struct acm *acm = container_of(port, struct acm, port);
707 	struct urb *urb;
708 	struct acm_wb *wb;
709 
710 	/*
711 	 * Need to grab write_lock to prevent race with resume, but no need to
712 	 * hold it due to the tty-port initialised flag.
713 	 */
714 	spin_lock_irq(&acm->write_lock);
715 	spin_unlock_irq(&acm->write_lock);
716 
717 	usb_autopm_get_interface_no_resume(acm->control);
718 	acm->control->needs_remote_wakeup = 0;
719 	usb_autopm_put_interface(acm->control);
720 
721 	for (;;) {
722 		urb = usb_get_from_anchor(&acm->delayed);
723 		if (!urb)
724 			break;
725 		wb = urb->context;
726 		wb->use = 0;
727 		usb_autopm_put_interface_async(acm->control);
728 	}
729 
730 	acm_kill_urbs(acm);
731 }
732 
733 static void acm_tty_cleanup(struct tty_struct *tty)
734 {
735 	struct acm *acm = tty->driver_data;
736 
737 	tty_port_put(&acm->port);
738 }
739 
740 static void acm_tty_hangup(struct tty_struct *tty)
741 {
742 	struct acm *acm = tty->driver_data;
743 
744 	tty_port_hangup(&acm->port);
745 }
746 
747 static void acm_tty_close(struct tty_struct *tty, struct file *filp)
748 {
749 	struct acm *acm = tty->driver_data;
750 
751 	tty_port_close(&acm->port, tty, filp);
752 }
753 
754 static int acm_tty_write(struct tty_struct *tty,
755 					const unsigned char *buf, int count)
756 {
757 	struct acm *acm = tty->driver_data;
758 	int stat;
759 	unsigned long flags;
760 	int wbn;
761 	struct acm_wb *wb;
762 
763 	if (!count)
764 		return 0;
765 
766 	dev_vdbg(&acm->data->dev, "%d bytes from tty layer\n", count);
767 
768 	spin_lock_irqsave(&acm->write_lock, flags);
769 	wbn = acm_wb_alloc(acm);
770 	if (wbn < 0) {
771 		spin_unlock_irqrestore(&acm->write_lock, flags);
772 		return 0;
773 	}
774 	wb = &acm->wb[wbn];
775 
776 	if (!acm->dev) {
777 		wb->use = 0;
778 		spin_unlock_irqrestore(&acm->write_lock, flags);
779 		return -ENODEV;
780 	}
781 
782 	count = (count > acm->writesize) ? acm->writesize : count;
783 	dev_vdbg(&acm->data->dev, "writing %d bytes\n", count);
784 	memcpy(wb->buf, buf, count);
785 	wb->len = count;
786 
787 	stat = usb_autopm_get_interface_async(acm->control);
788 	if (stat) {
789 		wb->use = 0;
790 		spin_unlock_irqrestore(&acm->write_lock, flags);
791 		return stat;
792 	}
793 
794 	if (acm->susp_count) {
795 		if (acm->putbuffer) {
796 			/* now to preserve order */
797 			usb_anchor_urb(acm->putbuffer->urb, &acm->delayed);
798 			acm->putbuffer = NULL;
799 		}
800 		usb_anchor_urb(wb->urb, &acm->delayed);
801 		spin_unlock_irqrestore(&acm->write_lock, flags);
802 		return count;
803 	} else {
804 		if (acm->putbuffer) {
805 			/* at this point there is no good way to handle errors */
806 			acm_start_wb(acm, acm->putbuffer);
807 			acm->putbuffer = NULL;
808 		}
809 	}
810 
811 	stat = acm_start_wb(acm, wb);
812 	spin_unlock_irqrestore(&acm->write_lock, flags);
813 
814 	if (stat < 0)
815 		return stat;
816 	return count;
817 }
818 
819 static void acm_tty_flush_chars(struct tty_struct *tty)
820 {
821 	struct acm *acm = tty->driver_data;
822 	struct acm_wb *cur = acm->putbuffer;
823 	int err;
824 	unsigned long flags;
825 
826 	if (!cur) /* nothing to do */
827 		return;
828 
829 	acm->putbuffer = NULL;
830 	err = usb_autopm_get_interface_async(acm->control);
831 	spin_lock_irqsave(&acm->write_lock, flags);
832 	if (err < 0) {
833 		cur->use = 0;
834 		acm->putbuffer = cur;
835 		goto out;
836 	}
837 
838 	if (acm->susp_count)
839 		usb_anchor_urb(cur->urb, &acm->delayed);
840 	else
841 		acm_start_wb(acm, cur);
842 out:
843 	spin_unlock_irqrestore(&acm->write_lock, flags);
844 	return;
845 }
846 
847 static int acm_tty_put_char(struct tty_struct *tty, unsigned char ch)
848 {
849 	struct acm *acm = tty->driver_data;
850 	struct acm_wb *cur;
851 	int wbn;
852 	unsigned long flags;
853 
854 overflow:
855 	cur = acm->putbuffer;
856 	if (!cur) {
857 		spin_lock_irqsave(&acm->write_lock, flags);
858 		wbn = acm_wb_alloc(acm);
859 		if (wbn >= 0) {
860 			cur = &acm->wb[wbn];
861 			acm->putbuffer = cur;
862 		}
863 		spin_unlock_irqrestore(&acm->write_lock, flags);
864 		if (!cur)
865 			return 0;
866 	}
867 
868 	if (cur->len == acm->writesize) {
869 		acm_tty_flush_chars(tty);
870 		goto overflow;
871 	}
872 
873 	cur->buf[cur->len++] = ch;
874 	return 1;
875 }
876 
877 static int acm_tty_write_room(struct tty_struct *tty)
878 {
879 	struct acm *acm = tty->driver_data;
880 	/*
881 	 * Do not let the line discipline to know that we have a reserve,
882 	 * or it might get too enthusiastic.
883 	 */
884 	return acm_wb_is_avail(acm) ? acm->writesize : 0;
885 }
886 
887 static int acm_tty_chars_in_buffer(struct tty_struct *tty)
888 {
889 	struct acm *acm = tty->driver_data;
890 	/*
891 	 * if the device was unplugged then any remaining characters fell out
892 	 * of the connector ;)
893 	 */
894 	if (acm->disconnected)
895 		return 0;
896 	/*
897 	 * This is inaccurate (overcounts), but it works.
898 	 */
899 	return (ACM_NW - acm_wb_is_avail(acm)) * acm->writesize;
900 }
901 
902 static void acm_tty_throttle(struct tty_struct *tty)
903 {
904 	struct acm *acm = tty->driver_data;
905 
906 	spin_lock_irq(&acm->read_lock);
907 	acm->throttle_req = 1;
908 	spin_unlock_irq(&acm->read_lock);
909 }
910 
911 static void acm_tty_unthrottle(struct tty_struct *tty)
912 {
913 	struct acm *acm = tty->driver_data;
914 	unsigned int was_throttled;
915 
916 	spin_lock_irq(&acm->read_lock);
917 	was_throttled = acm->throttled;
918 	acm->throttled = 0;
919 	acm->throttle_req = 0;
920 	spin_unlock_irq(&acm->read_lock);
921 
922 	if (was_throttled)
923 		acm_submit_read_urbs(acm, GFP_KERNEL);
924 }
925 
926 static int acm_tty_break_ctl(struct tty_struct *tty, int state)
927 {
928 	struct acm *acm = tty->driver_data;
929 	int retval;
930 
931 	retval = acm_send_break(acm, state ? 0xffff : 0);
932 	if (retval < 0)
933 		dev_dbg(&acm->control->dev,
934 			"%s - send break failed\n", __func__);
935 	return retval;
936 }
937 
938 static int acm_tty_tiocmget(struct tty_struct *tty)
939 {
940 	struct acm *acm = tty->driver_data;
941 
942 	return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
943 	       (acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
944 	       (acm->ctrlin  & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
945 	       (acm->ctrlin  & ACM_CTRL_RI  ? TIOCM_RI  : 0) |
946 	       (acm->ctrlin  & ACM_CTRL_DCD ? TIOCM_CD  : 0) |
947 	       TIOCM_CTS;
948 }
949 
950 static int acm_tty_tiocmset(struct tty_struct *tty,
951 			    unsigned int set, unsigned int clear)
952 {
953 	struct acm *acm = tty->driver_data;
954 	unsigned int newctrl;
955 
956 	newctrl = acm->ctrlout;
957 	set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
958 					(set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
959 	clear = (clear & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
960 					(clear & TIOCM_RTS ? ACM_CTRL_RTS : 0);
961 
962 	newctrl = (newctrl & ~clear) | set;
963 
964 	if (acm->ctrlout == newctrl)
965 		return 0;
966 	return acm_set_control(acm, acm->ctrlout = newctrl);
967 }
968 
969 static int get_serial_info(struct acm *acm, struct serial_struct __user *info)
970 {
971 	struct serial_struct tmp;
972 
973 	memset(&tmp, 0, sizeof(tmp));
974 	tmp.xmit_fifo_size = acm->writesize;
975 	tmp.baud_base = le32_to_cpu(acm->line.dwDTERate);
976 	tmp.close_delay	= acm->port.close_delay / 10;
977 	tmp.closing_wait = acm->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
978 				ASYNC_CLOSING_WAIT_NONE :
979 				acm->port.closing_wait / 10;
980 
981 	if (copy_to_user(info, &tmp, sizeof(tmp)))
982 		return -EFAULT;
983 	else
984 		return 0;
985 }
986 
987 static int set_serial_info(struct acm *acm,
988 				struct serial_struct __user *newinfo)
989 {
990 	struct serial_struct new_serial;
991 	unsigned int closing_wait, close_delay;
992 	int retval = 0;
993 
994 	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
995 		return -EFAULT;
996 
997 	close_delay = new_serial.close_delay * 10;
998 	closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
999 			ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
1000 
1001 	mutex_lock(&acm->port.mutex);
1002 
1003 	if (!capable(CAP_SYS_ADMIN)) {
1004 		if ((close_delay != acm->port.close_delay) ||
1005 		    (closing_wait != acm->port.closing_wait))
1006 			retval = -EPERM;
1007 		else
1008 			retval = -EOPNOTSUPP;
1009 	} else {
1010 		acm->port.close_delay  = close_delay;
1011 		acm->port.closing_wait = closing_wait;
1012 	}
1013 
1014 	mutex_unlock(&acm->port.mutex);
1015 	return retval;
1016 }
1017 
1018 static int wait_serial_change(struct acm *acm, unsigned long arg)
1019 {
1020 	int rv = 0;
1021 	DECLARE_WAITQUEUE(wait, current);
1022 	struct async_icount old, new;
1023 
1024 	do {
1025 		spin_lock_irq(&acm->read_lock);
1026 		old = acm->oldcount;
1027 		new = acm->iocount;
1028 		acm->oldcount = new;
1029 		spin_unlock_irq(&acm->read_lock);
1030 
1031 		if ((arg & TIOCM_DSR) &&
1032 			old.dsr != new.dsr)
1033 			break;
1034 		if ((arg & TIOCM_CD)  &&
1035 			old.dcd != new.dcd)
1036 			break;
1037 		if ((arg & TIOCM_RI) &&
1038 			old.rng != new.rng)
1039 			break;
1040 
1041 		add_wait_queue(&acm->wioctl, &wait);
1042 		set_current_state(TASK_INTERRUPTIBLE);
1043 		schedule();
1044 		remove_wait_queue(&acm->wioctl, &wait);
1045 		if (acm->disconnected) {
1046 			if (arg & TIOCM_CD)
1047 				break;
1048 			else
1049 				rv = -ENODEV;
1050 		} else {
1051 			if (signal_pending(current))
1052 				rv = -ERESTARTSYS;
1053 		}
1054 	} while (!rv);
1055 
1056 
1057 
1058 	return rv;
1059 }
1060 
1061 static int acm_tty_get_icount(struct tty_struct *tty,
1062 					struct serial_icounter_struct *icount)
1063 {
1064 	struct acm *acm = tty->driver_data;
1065 
1066 	icount->dsr = acm->iocount.dsr;
1067 	icount->rng = acm->iocount.rng;
1068 	icount->dcd = acm->iocount.dcd;
1069 	icount->frame = acm->iocount.frame;
1070 	icount->overrun = acm->iocount.overrun;
1071 	icount->parity = acm->iocount.parity;
1072 	icount->brk = acm->iocount.brk;
1073 
1074 	return 0;
1075 }
1076 
1077 static int acm_tty_ioctl(struct tty_struct *tty,
1078 					unsigned int cmd, unsigned long arg)
1079 {
1080 	struct acm *acm = tty->driver_data;
1081 	int rv = -ENOIOCTLCMD;
1082 
1083 	switch (cmd) {
1084 	case TIOCGSERIAL: /* gets serial port data */
1085 		rv = get_serial_info(acm, (struct serial_struct __user *) arg);
1086 		break;
1087 	case TIOCSSERIAL:
1088 		rv = set_serial_info(acm, (struct serial_struct __user *) arg);
1089 		break;
1090 	case TIOCMIWAIT:
1091 		rv = usb_autopm_get_interface(acm->control);
1092 		if (rv < 0) {
1093 			rv = -EIO;
1094 			break;
1095 		}
1096 		rv = wait_serial_change(acm, arg);
1097 		usb_autopm_put_interface(acm->control);
1098 		break;
1099 	}
1100 
1101 	return rv;
1102 }
1103 
1104 static void acm_tty_set_termios(struct tty_struct *tty,
1105 						struct ktermios *termios_old)
1106 {
1107 	struct acm *acm = tty->driver_data;
1108 	struct ktermios *termios = &tty->termios;
1109 	struct usb_cdc_line_coding newline;
1110 	int newctrl = acm->ctrlout;
1111 
1112 	newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
1113 	newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
1114 	newline.bParityType = termios->c_cflag & PARENB ?
1115 				(termios->c_cflag & PARODD ? 1 : 2) +
1116 				(termios->c_cflag & CMSPAR ? 2 : 0) : 0;
1117 	switch (termios->c_cflag & CSIZE) {
1118 	case CS5:
1119 		newline.bDataBits = 5;
1120 		break;
1121 	case CS6:
1122 		newline.bDataBits = 6;
1123 		break;
1124 	case CS7:
1125 		newline.bDataBits = 7;
1126 		break;
1127 	case CS8:
1128 	default:
1129 		newline.bDataBits = 8;
1130 		break;
1131 	}
1132 	/* FIXME: Needs to clear unsupported bits in the termios */
1133 	acm->clocal = ((termios->c_cflag & CLOCAL) != 0);
1134 
1135 	if (C_BAUD(tty) == B0) {
1136 		newline.dwDTERate = acm->line.dwDTERate;
1137 		newctrl &= ~ACM_CTRL_DTR;
1138 	} else if (termios_old && (termios_old->c_cflag & CBAUD) == B0) {
1139 		newctrl |=  ACM_CTRL_DTR;
1140 	}
1141 
1142 	if (newctrl != acm->ctrlout)
1143 		acm_set_control(acm, acm->ctrlout = newctrl);
1144 
1145 	if (memcmp(&acm->line, &newline, sizeof newline)) {
1146 		memcpy(&acm->line, &newline, sizeof newline);
1147 		dev_dbg(&acm->control->dev, "%s - set line: %d %d %d %d\n",
1148 			__func__,
1149 			le32_to_cpu(newline.dwDTERate),
1150 			newline.bCharFormat, newline.bParityType,
1151 			newline.bDataBits);
1152 		acm_set_line(acm, &acm->line);
1153 	}
1154 }
1155 
1156 static const struct tty_port_operations acm_port_ops = {
1157 	.dtr_rts = acm_port_dtr_rts,
1158 	.shutdown = acm_port_shutdown,
1159 	.activate = acm_port_activate,
1160 	.destruct = acm_port_destruct,
1161 };
1162 
1163 /*
1164  * USB probe and disconnect routines.
1165  */
1166 
1167 /* Little helpers: write/read buffers free */
1168 static void acm_write_buffers_free(struct acm *acm)
1169 {
1170 	int i;
1171 	struct acm_wb *wb;
1172 
1173 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++)
1174 		usb_free_coherent(acm->dev, acm->writesize, wb->buf, wb->dmah);
1175 }
1176 
1177 static void acm_read_buffers_free(struct acm *acm)
1178 {
1179 	int i;
1180 
1181 	for (i = 0; i < acm->rx_buflimit; i++)
1182 		usb_free_coherent(acm->dev, acm->readsize,
1183 			  acm->read_buffers[i].base, acm->read_buffers[i].dma);
1184 }
1185 
1186 /* Little helper: write buffers allocate */
1187 static int acm_write_buffers_alloc(struct acm *acm)
1188 {
1189 	int i;
1190 	struct acm_wb *wb;
1191 
1192 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++) {
1193 		wb->buf = usb_alloc_coherent(acm->dev, acm->writesize, GFP_KERNEL,
1194 		    &wb->dmah);
1195 		if (!wb->buf) {
1196 			while (i != 0) {
1197 				--i;
1198 				--wb;
1199 				usb_free_coherent(acm->dev, acm->writesize,
1200 				    wb->buf, wb->dmah);
1201 			}
1202 			return -ENOMEM;
1203 		}
1204 	}
1205 	return 0;
1206 }
1207 
1208 static int acm_probe(struct usb_interface *intf,
1209 		     const struct usb_device_id *id)
1210 {
1211 	struct usb_cdc_union_desc *union_header = NULL;
1212 	struct usb_cdc_call_mgmt_descriptor *cmgmd = NULL;
1213 	unsigned char *buffer = intf->altsetting->extra;
1214 	int buflen = intf->altsetting->extralen;
1215 	struct usb_interface *control_interface;
1216 	struct usb_interface *data_interface;
1217 	struct usb_endpoint_descriptor *epctrl = NULL;
1218 	struct usb_endpoint_descriptor *epread = NULL;
1219 	struct usb_endpoint_descriptor *epwrite = NULL;
1220 	struct usb_device *usb_dev = interface_to_usbdev(intf);
1221 	struct usb_cdc_parsed_header h;
1222 	struct acm *acm;
1223 	int minor;
1224 	int ctrlsize, readsize;
1225 	u8 *buf;
1226 	int call_intf_num = -1;
1227 	int data_intf_num = -1;
1228 	unsigned long quirks;
1229 	int num_rx_buf;
1230 	int i;
1231 	int combined_interfaces = 0;
1232 	struct device *tty_dev;
1233 	int rv = -ENOMEM;
1234 	int res;
1235 
1236 	/* normal quirks */
1237 	quirks = (unsigned long)id->driver_info;
1238 
1239 	if (quirks == IGNORE_DEVICE)
1240 		return -ENODEV;
1241 
1242 	memset(&h, 0x00, sizeof(struct usb_cdc_parsed_header));
1243 
1244 	num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;
1245 
1246 	/* handle quirks deadly to normal probing*/
1247 	if (quirks == NO_UNION_NORMAL) {
1248 		data_interface = usb_ifnum_to_if(usb_dev, 1);
1249 		control_interface = usb_ifnum_to_if(usb_dev, 0);
1250 		/* we would crash */
1251 		if (!data_interface || !control_interface)
1252 			return -ENODEV;
1253 		goto skip_normal_probe;
1254 	}
1255 
1256 	/* normal probing*/
1257 	if (!buffer) {
1258 		dev_err(&intf->dev, "Weird descriptor references\n");
1259 		return -EINVAL;
1260 	}
1261 
1262 	if (!intf->cur_altsetting)
1263 		return -EINVAL;
1264 
1265 	if (!buflen) {
1266 		if (intf->cur_altsetting->endpoint &&
1267 				intf->cur_altsetting->endpoint->extralen &&
1268 				intf->cur_altsetting->endpoint->extra) {
1269 			dev_dbg(&intf->dev,
1270 				"Seeking extra descriptors on endpoint\n");
1271 			buflen = intf->cur_altsetting->endpoint->extralen;
1272 			buffer = intf->cur_altsetting->endpoint->extra;
1273 		} else {
1274 			dev_err(&intf->dev,
1275 				"Zero length descriptor references\n");
1276 			return -EINVAL;
1277 		}
1278 	}
1279 
1280 	cdc_parse_cdc_header(&h, intf, buffer, buflen);
1281 	union_header = h.usb_cdc_union_desc;
1282 	cmgmd = h.usb_cdc_call_mgmt_descriptor;
1283 	if (cmgmd)
1284 		call_intf_num = cmgmd->bDataInterface;
1285 
1286 	if (!union_header) {
1287 		if (call_intf_num > 0) {
1288 			dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n");
1289 			/* quirks for Droids MuIn LCD */
1290 			if (quirks & NO_DATA_INTERFACE) {
1291 				data_interface = usb_ifnum_to_if(usb_dev, 0);
1292 			} else {
1293 				data_intf_num = call_intf_num;
1294 				data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
1295 			}
1296 			control_interface = intf;
1297 		} else {
1298 			if (intf->cur_altsetting->desc.bNumEndpoints != 3) {
1299 				dev_dbg(&intf->dev,"No union descriptor, giving up\n");
1300 				return -ENODEV;
1301 			} else {
1302 				dev_warn(&intf->dev,"No union descriptor, testing for castrated device\n");
1303 				combined_interfaces = 1;
1304 				control_interface = data_interface = intf;
1305 				goto look_for_collapsed_interface;
1306 			}
1307 		}
1308 	} else {
1309 		data_intf_num = union_header->bSlaveInterface0;
1310 		control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
1311 		data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
1312 	}
1313 
1314 	if (!control_interface || !data_interface) {
1315 		dev_dbg(&intf->dev, "no interfaces\n");
1316 		return -ENODEV;
1317 	}
1318 	if (!data_interface->cur_altsetting || !control_interface->cur_altsetting)
1319 		return -ENODEV;
1320 
1321 	if (data_intf_num != call_intf_num)
1322 		dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");
1323 
1324 	if (control_interface == data_interface) {
1325 		/* some broken devices designed for windows work this way */
1326 		dev_warn(&intf->dev,"Control and data interfaces are not separated!\n");
1327 		combined_interfaces = 1;
1328 		/* a popular other OS doesn't use it */
1329 		quirks |= NO_CAP_LINE;
1330 		if (data_interface->cur_altsetting->desc.bNumEndpoints != 3) {
1331 			dev_err(&intf->dev, "This needs exactly 3 endpoints\n");
1332 			return -EINVAL;
1333 		}
1334 look_for_collapsed_interface:
1335 		res = usb_find_common_endpoints(data_interface->cur_altsetting,
1336 				&epread, &epwrite, &epctrl, NULL);
1337 		if (res)
1338 			return res;
1339 
1340 		goto made_compressed_probe;
1341 	}
1342 
1343 skip_normal_probe:
1344 
1345 	/*workaround for switched interfaces */
1346 	if (data_interface->cur_altsetting->desc.bInterfaceClass
1347 						!= CDC_DATA_INTERFACE_TYPE) {
1348 		if (control_interface->cur_altsetting->desc.bInterfaceClass
1349 						== CDC_DATA_INTERFACE_TYPE) {
1350 			dev_dbg(&intf->dev,
1351 				"Your device has switched interfaces.\n");
1352 			swap(control_interface, data_interface);
1353 		} else {
1354 			return -EINVAL;
1355 		}
1356 	}
1357 
1358 	/* Accept probe requests only for the control interface */
1359 	if (!combined_interfaces && intf != control_interface)
1360 		return -ENODEV;
1361 
1362 	if (!combined_interfaces && usb_interface_claimed(data_interface)) {
1363 		/* valid in this context */
1364 		dev_dbg(&intf->dev, "The data interface isn't available\n");
1365 		return -EBUSY;
1366 	}
1367 
1368 
1369 	if (data_interface->cur_altsetting->desc.bNumEndpoints < 2 ||
1370 	    control_interface->cur_altsetting->desc.bNumEndpoints == 0)
1371 		return -EINVAL;
1372 
1373 	epctrl = &control_interface->cur_altsetting->endpoint[0].desc;
1374 	epread = &data_interface->cur_altsetting->endpoint[0].desc;
1375 	epwrite = &data_interface->cur_altsetting->endpoint[1].desc;
1376 
1377 
1378 	/* workaround for switched endpoints */
1379 	if (!usb_endpoint_dir_in(epread)) {
1380 		/* descriptors are swapped */
1381 		dev_dbg(&intf->dev,
1382 			"The data interface has switched endpoints\n");
1383 		swap(epread, epwrite);
1384 	}
1385 made_compressed_probe:
1386 	dev_dbg(&intf->dev, "interfaces are valid\n");
1387 
1388 	acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
1389 	if (acm == NULL)
1390 		goto alloc_fail;
1391 
1392 	minor = acm_alloc_minor(acm);
1393 	if (minor < 0)
1394 		goto alloc_fail1;
1395 
1396 	ctrlsize = usb_endpoint_maxp(epctrl);
1397 	readsize = usb_endpoint_maxp(epread) *
1398 				(quirks == SINGLE_RX_URB ? 1 : 2);
1399 	acm->combined_interfaces = combined_interfaces;
1400 	acm->writesize = usb_endpoint_maxp(epwrite) * 20;
1401 	acm->control = control_interface;
1402 	acm->data = data_interface;
1403 	acm->minor = minor;
1404 	acm->dev = usb_dev;
1405 	if (h.usb_cdc_acm_descriptor)
1406 		acm->ctrl_caps = h.usb_cdc_acm_descriptor->bmCapabilities;
1407 	if (quirks & NO_CAP_LINE)
1408 		acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
1409 	acm->ctrlsize = ctrlsize;
1410 	acm->readsize = readsize;
1411 	acm->rx_buflimit = num_rx_buf;
1412 	INIT_WORK(&acm->work, acm_softint);
1413 	init_waitqueue_head(&acm->wioctl);
1414 	spin_lock_init(&acm->write_lock);
1415 	spin_lock_init(&acm->read_lock);
1416 	mutex_init(&acm->mutex);
1417 	if (usb_endpoint_xfer_int(epread)) {
1418 		acm->bInterval = epread->bInterval;
1419 		acm->in = usb_rcvintpipe(usb_dev, epread->bEndpointAddress);
1420 	} else {
1421 		acm->in = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
1422 	}
1423 	if (usb_endpoint_xfer_int(epwrite))
1424 		acm->out = usb_sndintpipe(usb_dev, epwrite->bEndpointAddress);
1425 	else
1426 		acm->out = usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress);
1427 	tty_port_init(&acm->port);
1428 	acm->port.ops = &acm_port_ops;
1429 	init_usb_anchor(&acm->delayed);
1430 	acm->quirks = quirks;
1431 
1432 	buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
1433 	if (!buf)
1434 		goto alloc_fail2;
1435 	acm->ctrl_buffer = buf;
1436 
1437 	if (acm_write_buffers_alloc(acm) < 0)
1438 		goto alloc_fail4;
1439 
1440 	acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
1441 	if (!acm->ctrlurb)
1442 		goto alloc_fail5;
1443 
1444 	for (i = 0; i < num_rx_buf; i++) {
1445 		struct acm_rb *rb = &(acm->read_buffers[i]);
1446 		struct urb *urb;
1447 
1448 		rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
1449 								&rb->dma);
1450 		if (!rb->base)
1451 			goto alloc_fail6;
1452 		rb->index = i;
1453 		rb->instance = acm;
1454 
1455 		urb = usb_alloc_urb(0, GFP_KERNEL);
1456 		if (!urb)
1457 			goto alloc_fail6;
1458 
1459 		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1460 		urb->transfer_dma = rb->dma;
1461 		if (usb_endpoint_xfer_int(epread))
1462 			usb_fill_int_urb(urb, acm->dev, acm->in, rb->base,
1463 					 acm->readsize,
1464 					 acm_read_bulk_callback, rb,
1465 					 acm->bInterval);
1466 		else
1467 			usb_fill_bulk_urb(urb, acm->dev, acm->in, rb->base,
1468 					  acm->readsize,
1469 					  acm_read_bulk_callback, rb);
1470 
1471 		acm->read_urbs[i] = urb;
1472 		__set_bit(i, &acm->read_urbs_free);
1473 	}
1474 	for (i = 0; i < ACM_NW; i++) {
1475 		struct acm_wb *snd = &(acm->wb[i]);
1476 
1477 		snd->urb = usb_alloc_urb(0, GFP_KERNEL);
1478 		if (snd->urb == NULL)
1479 			goto alloc_fail7;
1480 
1481 		if (usb_endpoint_xfer_int(epwrite))
1482 			usb_fill_int_urb(snd->urb, usb_dev, acm->out,
1483 				NULL, acm->writesize, acm_write_bulk, snd, epwrite->bInterval);
1484 		else
1485 			usb_fill_bulk_urb(snd->urb, usb_dev, acm->out,
1486 				NULL, acm->writesize, acm_write_bulk, snd);
1487 		snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1488 		if (quirks & SEND_ZERO_PACKET)
1489 			snd->urb->transfer_flags |= URB_ZERO_PACKET;
1490 		snd->instance = acm;
1491 	}
1492 
1493 	usb_set_intfdata(intf, acm);
1494 
1495 	i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
1496 	if (i < 0)
1497 		goto alloc_fail7;
1498 
1499 	if (h.usb_cdc_country_functional_desc) { /* export the country data */
1500 		struct usb_cdc_country_functional_desc * cfd =
1501 					h.usb_cdc_country_functional_desc;
1502 
1503 		acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
1504 		if (!acm->country_codes)
1505 			goto skip_countries;
1506 		acm->country_code_size = cfd->bLength - 4;
1507 		memcpy(acm->country_codes, (u8 *)&cfd->wCountyCode0,
1508 							cfd->bLength - 4);
1509 		acm->country_rel_date = cfd->iCountryCodeRelDate;
1510 
1511 		i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
1512 		if (i < 0) {
1513 			kfree(acm->country_codes);
1514 			acm->country_codes = NULL;
1515 			acm->country_code_size = 0;
1516 			goto skip_countries;
1517 		}
1518 
1519 		i = device_create_file(&intf->dev,
1520 						&dev_attr_iCountryCodeRelDate);
1521 		if (i < 0) {
1522 			device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
1523 			kfree(acm->country_codes);
1524 			acm->country_codes = NULL;
1525 			acm->country_code_size = 0;
1526 			goto skip_countries;
1527 		}
1528 	}
1529 
1530 skip_countries:
1531 	usb_fill_int_urb(acm->ctrlurb, usb_dev,
1532 			 usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
1533 			 acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
1534 			 /* works around buggy devices */
1535 			 epctrl->bInterval ? epctrl->bInterval : 16);
1536 	acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1537 	acm->ctrlurb->transfer_dma = acm->ctrl_dma;
1538 	acm->notification_buffer = NULL;
1539 	acm->nb_index = 0;
1540 	acm->nb_size = 0;
1541 
1542 	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
1543 
1544 	acm->line.dwDTERate = cpu_to_le32(9600);
1545 	acm->line.bDataBits = 8;
1546 	acm_set_line(acm, &acm->line);
1547 
1548 	usb_driver_claim_interface(&acm_driver, data_interface, acm);
1549 	usb_set_intfdata(data_interface, acm);
1550 
1551 	usb_get_intf(control_interface);
1552 	tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
1553 			&control_interface->dev);
1554 	if (IS_ERR(tty_dev)) {
1555 		rv = PTR_ERR(tty_dev);
1556 		goto alloc_fail8;
1557 	}
1558 
1559 	if (quirks & CLEAR_HALT_CONDITIONS) {
1560 		usb_clear_halt(usb_dev, acm->in);
1561 		usb_clear_halt(usb_dev, acm->out);
1562 	}
1563 
1564 	return 0;
1565 alloc_fail8:
1566 	if (acm->country_codes) {
1567 		device_remove_file(&acm->control->dev,
1568 				&dev_attr_wCountryCodes);
1569 		device_remove_file(&acm->control->dev,
1570 				&dev_attr_iCountryCodeRelDate);
1571 		kfree(acm->country_codes);
1572 	}
1573 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1574 alloc_fail7:
1575 	usb_set_intfdata(intf, NULL);
1576 	for (i = 0; i < ACM_NW; i++)
1577 		usb_free_urb(acm->wb[i].urb);
1578 alloc_fail6:
1579 	for (i = 0; i < num_rx_buf; i++)
1580 		usb_free_urb(acm->read_urbs[i]);
1581 	acm_read_buffers_free(acm);
1582 	usb_free_urb(acm->ctrlurb);
1583 alloc_fail5:
1584 	acm_write_buffers_free(acm);
1585 alloc_fail4:
1586 	usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1587 alloc_fail2:
1588 	acm_release_minor(acm);
1589 alloc_fail1:
1590 	kfree(acm);
1591 alloc_fail:
1592 	return rv;
1593 }
1594 
1595 static void acm_disconnect(struct usb_interface *intf)
1596 {
1597 	struct acm *acm = usb_get_intfdata(intf);
1598 	struct tty_struct *tty;
1599 
1600 	/* sibling interface is already cleaning up */
1601 	if (!acm)
1602 		return;
1603 
1604 	mutex_lock(&acm->mutex);
1605 	acm->disconnected = true;
1606 	if (acm->country_codes) {
1607 		device_remove_file(&acm->control->dev,
1608 				&dev_attr_wCountryCodes);
1609 		device_remove_file(&acm->control->dev,
1610 				&dev_attr_iCountryCodeRelDate);
1611 	}
1612 	wake_up_all(&acm->wioctl);
1613 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1614 	usb_set_intfdata(acm->control, NULL);
1615 	usb_set_intfdata(acm->data, NULL);
1616 	mutex_unlock(&acm->mutex);
1617 
1618 	tty = tty_port_tty_get(&acm->port);
1619 	if (tty) {
1620 		tty_vhangup(tty);
1621 		tty_kref_put(tty);
1622 	}
1623 
1624 	acm_kill_urbs(acm);
1625 	cancel_work_sync(&acm->work);
1626 
1627 	tty_unregister_device(acm_tty_driver, acm->minor);
1628 
1629 	acm_write_buffers_free(acm);
1630 	usb_free_coherent(acm->dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1631 	acm_read_buffers_free(acm);
1632 
1633 	kfree(acm->notification_buffer);
1634 
1635 	if (!acm->combined_interfaces)
1636 		usb_driver_release_interface(&acm_driver, intf == acm->control ?
1637 					acm->data : acm->control);
1638 
1639 	tty_port_put(&acm->port);
1640 }
1641 
1642 #ifdef CONFIG_PM
1643 static int acm_suspend(struct usb_interface *intf, pm_message_t message)
1644 {
1645 	struct acm *acm = usb_get_intfdata(intf);
1646 	int cnt;
1647 
1648 	spin_lock_irq(&acm->write_lock);
1649 	if (PMSG_IS_AUTO(message)) {
1650 		if (acm->transmitting) {
1651 			spin_unlock_irq(&acm->write_lock);
1652 			return -EBUSY;
1653 		}
1654 	}
1655 	cnt = acm->susp_count++;
1656 	spin_unlock_irq(&acm->write_lock);
1657 
1658 	if (cnt)
1659 		return 0;
1660 
1661 	acm_kill_urbs(acm);
1662 	cancel_work_sync(&acm->work);
1663 
1664 	return 0;
1665 }
1666 
1667 static int acm_resume(struct usb_interface *intf)
1668 {
1669 	struct acm *acm = usb_get_intfdata(intf);
1670 	struct urb *urb;
1671 	int rv = 0;
1672 
1673 	spin_lock_irq(&acm->write_lock);
1674 
1675 	if (--acm->susp_count)
1676 		goto out;
1677 
1678 	if (tty_port_initialized(&acm->port)) {
1679 		rv = usb_submit_urb(acm->ctrlurb, GFP_ATOMIC);
1680 
1681 		for (;;) {
1682 			urb = usb_get_from_anchor(&acm->delayed);
1683 			if (!urb)
1684 				break;
1685 
1686 			acm_start_wb(acm, urb->context);
1687 		}
1688 
1689 		/*
1690 		 * delayed error checking because we must
1691 		 * do the write path at all cost
1692 		 */
1693 		if (rv < 0)
1694 			goto out;
1695 
1696 		rv = acm_submit_read_urbs(acm, GFP_ATOMIC);
1697 	}
1698 out:
1699 	spin_unlock_irq(&acm->write_lock);
1700 
1701 	return rv;
1702 }
1703 
1704 static int acm_reset_resume(struct usb_interface *intf)
1705 {
1706 	struct acm *acm = usb_get_intfdata(intf);
1707 
1708 	if (tty_port_initialized(&acm->port))
1709 		tty_port_tty_hangup(&acm->port, false);
1710 
1711 	return acm_resume(intf);
1712 }
1713 
1714 #endif /* CONFIG_PM */
1715 
1716 static int acm_pre_reset(struct usb_interface *intf)
1717 {
1718 	struct acm *acm = usb_get_intfdata(intf);
1719 
1720 	clear_bit(EVENT_RX_STALL, &acm->flags);
1721 
1722 	return 0;
1723 }
1724 
1725 #define NOKIA_PCSUITE_ACM_INFO(x) \
1726 		USB_DEVICE_AND_INTERFACE_INFO(0x0421, x, \
1727 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1728 		USB_CDC_ACM_PROTO_VENDOR)
1729 
1730 #define SAMSUNG_PCSUITE_ACM_INFO(x) \
1731 		USB_DEVICE_AND_INTERFACE_INFO(0x04e7, x, \
1732 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1733 		USB_CDC_ACM_PROTO_VENDOR)
1734 
1735 /*
1736  * USB driver structure.
1737  */
1738 
1739 static const struct usb_device_id acm_ids[] = {
1740 	/* quirky and broken devices */
1741 	{ USB_DEVICE(0x076d, 0x0006), /* Denso Cradle CU-321 */
1742 	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
1743 	{ USB_DEVICE(0x17ef, 0x7000), /* Lenovo USB modem */
1744 	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
1745 	{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
1746 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1747 	},
1748 	{ USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; andrey.arapov@gmail.com */
1749 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1750 	},
1751 	{ USB_DEVICE(0x0e8d, 0x3329), /* MediaTek Inc GPS */
1752 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1753 	},
1754 	{ USB_DEVICE(0x0482, 0x0203), /* KYOCERA AH-K3001V */
1755 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1756 	},
1757 	{ USB_DEVICE(0x079b, 0x000f), /* BT On-Air USB MODEM */
1758 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1759 	},
1760 	{ USB_DEVICE(0x0ace, 0x1602), /* ZyDAS 56K USB MODEM */
1761 	.driver_info = SINGLE_RX_URB,
1762 	},
1763 	{ USB_DEVICE(0x0ace, 0x1608), /* ZyDAS 56K USB MODEM */
1764 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1765 	},
1766 	{ USB_DEVICE(0x0ace, 0x1611), /* ZyDAS 56K USB MODEM - new version */
1767 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1768 	},
1769 	{ USB_DEVICE(0x22b8, 0x7000), /* Motorola Q Phone */
1770 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1771 	},
1772 	{ USB_DEVICE(0x0803, 0x3095), /* Zoom Telephonics Model 3095F USB MODEM */
1773 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1774 	},
1775 	{ USB_DEVICE(0x0572, 0x1321), /* Conexant USB MODEM CX93010 */
1776 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1777 	},
1778 	{ USB_DEVICE(0x0572, 0x1324), /* Conexant USB MODEM RD02-D400 */
1779 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1780 	},
1781 	{ USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */
1782 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1783 	},
1784 	{ USB_DEVICE(0x20df, 0x0001), /* Simtec Electronics Entropy Key */
1785 	.driver_info = QUIRK_CONTROL_LINE_STATE, },
1786 	{ USB_DEVICE(0x2184, 0x001c) },	/* GW Instek AFG-2225 */
1787 	{ USB_DEVICE(0x2184, 0x0036) },	/* GW Instek AFG-125 */
1788 	{ USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
1789 	},
1790 	/* Motorola H24 HSPA module: */
1791 	{ USB_DEVICE(0x22b8, 0x2d91) }, /* modem                                */
1792 	{ USB_DEVICE(0x22b8, 0x2d92),   /* modem           + diagnostics        */
1793 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1794 	},
1795 	{ USB_DEVICE(0x22b8, 0x2d93),   /* modem + AT port                      */
1796 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1797 	},
1798 	{ USB_DEVICE(0x22b8, 0x2d95),   /* modem + AT port + diagnostics        */
1799 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1800 	},
1801 	{ USB_DEVICE(0x22b8, 0x2d96),   /* modem                         + NMEA */
1802 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1803 	},
1804 	{ USB_DEVICE(0x22b8, 0x2d97),   /* modem           + diagnostics + NMEA */
1805 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1806 	},
1807 	{ USB_DEVICE(0x22b8, 0x2d99),   /* modem + AT port               + NMEA */
1808 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1809 	},
1810 	{ USB_DEVICE(0x22b8, 0x2d9a),   /* modem + AT port + diagnostics + NMEA */
1811 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1812 	},
1813 
1814 	{ USB_DEVICE(0x0572, 0x1329), /* Hummingbird huc56s (Conexant) */
1815 	.driver_info = NO_UNION_NORMAL, /* union descriptor misplaced on
1816 					   data interface instead of
1817 					   communications interface.
1818 					   Maybe we should define a new
1819 					   quirk for this. */
1820 	},
1821 	{ USB_DEVICE(0x0572, 0x1340), /* Conexant CX93010-2x UCMxx */
1822 	.driver_info = NO_UNION_NORMAL,
1823 	},
1824 	{ USB_DEVICE(0x05f9, 0x4002), /* PSC Scanning, Magellan 800i */
1825 	.driver_info = NO_UNION_NORMAL,
1826 	},
1827 	{ USB_DEVICE(0x1bbb, 0x0003), /* Alcatel OT-I650 */
1828 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1829 	},
1830 	{ USB_DEVICE(0x1576, 0x03b1), /* Maretron USB100 */
1831 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1832 	},
1833 	{ USB_DEVICE(0xfff0, 0x0100), /* DATECS FP-2000 */
1834 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1835 	},
1836 	{ USB_DEVICE(0x09d8, 0x0320), /* Elatec GmbH TWN3 */
1837 	.driver_info = NO_UNION_NORMAL, /* has misplaced union descriptor */
1838 	},
1839 
1840 	{ USB_DEVICE(0x2912, 0x0001), /* ATOL FPrint */
1841 	.driver_info = CLEAR_HALT_CONDITIONS,
1842 	},
1843 
1844 	/* Nokia S60 phones expose two ACM channels. The first is
1845 	 * a modem and is picked up by the standard AT-command
1846 	 * information below. The second is 'vendor-specific' but
1847 	 * is treated as a serial device at the S60 end, so we want
1848 	 * to expose it on Linux too. */
1849 	{ NOKIA_PCSUITE_ACM_INFO(0x042D), }, /* Nokia 3250 */
1850 	{ NOKIA_PCSUITE_ACM_INFO(0x04D8), }, /* Nokia 5500 Sport */
1851 	{ NOKIA_PCSUITE_ACM_INFO(0x04C9), }, /* Nokia E50 */
1852 	{ NOKIA_PCSUITE_ACM_INFO(0x0419), }, /* Nokia E60 */
1853 	{ NOKIA_PCSUITE_ACM_INFO(0x044D), }, /* Nokia E61 */
1854 	{ NOKIA_PCSUITE_ACM_INFO(0x0001), }, /* Nokia E61i */
1855 	{ NOKIA_PCSUITE_ACM_INFO(0x0475), }, /* Nokia E62 */
1856 	{ NOKIA_PCSUITE_ACM_INFO(0x0508), }, /* Nokia E65 */
1857 	{ NOKIA_PCSUITE_ACM_INFO(0x0418), }, /* Nokia E70 */
1858 	{ NOKIA_PCSUITE_ACM_INFO(0x0425), }, /* Nokia N71 */
1859 	{ NOKIA_PCSUITE_ACM_INFO(0x0486), }, /* Nokia N73 */
1860 	{ NOKIA_PCSUITE_ACM_INFO(0x04DF), }, /* Nokia N75 */
1861 	{ NOKIA_PCSUITE_ACM_INFO(0x000e), }, /* Nokia N77 */
1862 	{ NOKIA_PCSUITE_ACM_INFO(0x0445), }, /* Nokia N80 */
1863 	{ NOKIA_PCSUITE_ACM_INFO(0x042F), }, /* Nokia N91 & N91 8GB */
1864 	{ NOKIA_PCSUITE_ACM_INFO(0x048E), }, /* Nokia N92 */
1865 	{ NOKIA_PCSUITE_ACM_INFO(0x0420), }, /* Nokia N93 */
1866 	{ NOKIA_PCSUITE_ACM_INFO(0x04E6), }, /* Nokia N93i  */
1867 	{ NOKIA_PCSUITE_ACM_INFO(0x04B2), }, /* Nokia 5700 XpressMusic */
1868 	{ NOKIA_PCSUITE_ACM_INFO(0x0134), }, /* Nokia 6110 Navigator (China) */
1869 	{ NOKIA_PCSUITE_ACM_INFO(0x046E), }, /* Nokia 6110 Navigator */
1870 	{ NOKIA_PCSUITE_ACM_INFO(0x002f), }, /* Nokia 6120 classic &  */
1871 	{ NOKIA_PCSUITE_ACM_INFO(0x0088), }, /* Nokia 6121 classic */
1872 	{ NOKIA_PCSUITE_ACM_INFO(0x00fc), }, /* Nokia 6124 classic */
1873 	{ NOKIA_PCSUITE_ACM_INFO(0x0042), }, /* Nokia E51 */
1874 	{ NOKIA_PCSUITE_ACM_INFO(0x00b0), }, /* Nokia E66 */
1875 	{ NOKIA_PCSUITE_ACM_INFO(0x00ab), }, /* Nokia E71 */
1876 	{ NOKIA_PCSUITE_ACM_INFO(0x0481), }, /* Nokia N76 */
1877 	{ NOKIA_PCSUITE_ACM_INFO(0x0007), }, /* Nokia N81 & N81 8GB */
1878 	{ NOKIA_PCSUITE_ACM_INFO(0x0071), }, /* Nokia N82 */
1879 	{ NOKIA_PCSUITE_ACM_INFO(0x04F0), }, /* Nokia N95 & N95-3 NAM */
1880 	{ NOKIA_PCSUITE_ACM_INFO(0x0070), }, /* Nokia N95 8GB  */
1881 	{ NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1882 	{ NOKIA_PCSUITE_ACM_INFO(0x0099), }, /* Nokia 6210 Navigator, RM-367 */
1883 	{ NOKIA_PCSUITE_ACM_INFO(0x0128), }, /* Nokia 6210 Navigator, RM-419 */
1884 	{ NOKIA_PCSUITE_ACM_INFO(0x008f), }, /* Nokia 6220 Classic */
1885 	{ NOKIA_PCSUITE_ACM_INFO(0x00a0), }, /* Nokia 6650 */
1886 	{ NOKIA_PCSUITE_ACM_INFO(0x007b), }, /* Nokia N78 */
1887 	{ NOKIA_PCSUITE_ACM_INFO(0x0094), }, /* Nokia N85 */
1888 	{ NOKIA_PCSUITE_ACM_INFO(0x003a), }, /* Nokia N96 & N96-3  */
1889 	{ NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1890 	{ NOKIA_PCSUITE_ACM_INFO(0x0108), }, /* Nokia 5320 XpressMusic 2G */
1891 	{ NOKIA_PCSUITE_ACM_INFO(0x01f5), }, /* Nokia N97, RM-505 */
1892 	{ NOKIA_PCSUITE_ACM_INFO(0x02e3), }, /* Nokia 5230, RM-588 */
1893 	{ NOKIA_PCSUITE_ACM_INFO(0x0178), }, /* Nokia E63 */
1894 	{ NOKIA_PCSUITE_ACM_INFO(0x010e), }, /* Nokia E75 */
1895 	{ NOKIA_PCSUITE_ACM_INFO(0x02d9), }, /* Nokia 6760 Slide */
1896 	{ NOKIA_PCSUITE_ACM_INFO(0x01d0), }, /* Nokia E52 */
1897 	{ NOKIA_PCSUITE_ACM_INFO(0x0223), }, /* Nokia E72 */
1898 	{ NOKIA_PCSUITE_ACM_INFO(0x0275), }, /* Nokia X6 */
1899 	{ NOKIA_PCSUITE_ACM_INFO(0x026c), }, /* Nokia N97 Mini */
1900 	{ NOKIA_PCSUITE_ACM_INFO(0x0154), }, /* Nokia 5800 XpressMusic */
1901 	{ NOKIA_PCSUITE_ACM_INFO(0x04ce), }, /* Nokia E90 */
1902 	{ NOKIA_PCSUITE_ACM_INFO(0x01d4), }, /* Nokia E55 */
1903 	{ NOKIA_PCSUITE_ACM_INFO(0x0302), }, /* Nokia N8 */
1904 	{ NOKIA_PCSUITE_ACM_INFO(0x0335), }, /* Nokia E7 */
1905 	{ NOKIA_PCSUITE_ACM_INFO(0x03cd), }, /* Nokia C7 */
1906 	{ SAMSUNG_PCSUITE_ACM_INFO(0x6651), }, /* Samsung GTi8510 (INNOV8) */
1907 
1908 	/* Support for Owen devices */
1909 	{ USB_DEVICE(0x03eb, 0x0030), }, /* Owen SI30 */
1910 
1911 	/* NOTE: non-Nokia COMM/ACM/0xff is likely MSFT RNDIS... NOT a modem! */
1912 
1913 	/* Support for Droids MuIn LCD */
1914 	{ USB_DEVICE(0x04d8, 0x000b),
1915 	.driver_info = NO_DATA_INTERFACE,
1916 	},
1917 
1918 #if IS_ENABLED(CONFIG_INPUT_IMS_PCU)
1919 	{ USB_DEVICE(0x04d8, 0x0082),	/* Application mode */
1920 	.driver_info = IGNORE_DEVICE,
1921 	},
1922 	{ USB_DEVICE(0x04d8, 0x0083),	/* Bootloader mode */
1923 	.driver_info = IGNORE_DEVICE,
1924 	},
1925 #endif
1926 
1927 	/*Samsung phone in firmware update mode */
1928 	{ USB_DEVICE(0x04e8, 0x685d),
1929 	.driver_info = IGNORE_DEVICE,
1930 	},
1931 
1932 	/* Exclude Infineon Flash Loader utility */
1933 	{ USB_DEVICE(0x058b, 0x0041),
1934 	.driver_info = IGNORE_DEVICE,
1935 	},
1936 
1937 	/* control interfaces without any protocol set */
1938 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1939 		USB_CDC_PROTO_NONE) },
1940 
1941 	/* control interfaces with various AT-command sets */
1942 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1943 		USB_CDC_ACM_PROTO_AT_V25TER) },
1944 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1945 		USB_CDC_ACM_PROTO_AT_PCCA101) },
1946 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1947 		USB_CDC_ACM_PROTO_AT_PCCA101_WAKE) },
1948 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1949 		USB_CDC_ACM_PROTO_AT_GSM) },
1950 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1951 		USB_CDC_ACM_PROTO_AT_3G) },
1952 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1953 		USB_CDC_ACM_PROTO_AT_CDMA) },
1954 
1955 	{ USB_DEVICE(0x1519, 0x0452), /* Intel 7260 modem */
1956 	.driver_info = SEND_ZERO_PACKET,
1957 	},
1958 
1959 	{ }
1960 };
1961 
1962 MODULE_DEVICE_TABLE(usb, acm_ids);
1963 
1964 static struct usb_driver acm_driver = {
1965 	.name =		"cdc_acm",
1966 	.probe =	acm_probe,
1967 	.disconnect =	acm_disconnect,
1968 #ifdef CONFIG_PM
1969 	.suspend =	acm_suspend,
1970 	.resume =	acm_resume,
1971 	.reset_resume =	acm_reset_resume,
1972 #endif
1973 	.pre_reset =	acm_pre_reset,
1974 	.id_table =	acm_ids,
1975 #ifdef CONFIG_PM
1976 	.supports_autosuspend = 1,
1977 #endif
1978 	.disable_hub_initiated_lpm = 1,
1979 };
1980 
1981 /*
1982  * TTY driver structures.
1983  */
1984 
1985 static const struct tty_operations acm_ops = {
1986 	.install =		acm_tty_install,
1987 	.open =			acm_tty_open,
1988 	.close =		acm_tty_close,
1989 	.cleanup =		acm_tty_cleanup,
1990 	.hangup =		acm_tty_hangup,
1991 	.write =		acm_tty_write,
1992 	.put_char =		acm_tty_put_char,
1993 	.flush_chars =		acm_tty_flush_chars,
1994 	.write_room =		acm_tty_write_room,
1995 	.ioctl =		acm_tty_ioctl,
1996 	.throttle =		acm_tty_throttle,
1997 	.unthrottle =		acm_tty_unthrottle,
1998 	.chars_in_buffer =	acm_tty_chars_in_buffer,
1999 	.break_ctl =		acm_tty_break_ctl,
2000 	.set_termios =		acm_tty_set_termios,
2001 	.tiocmget =		acm_tty_tiocmget,
2002 	.tiocmset =		acm_tty_tiocmset,
2003 	.get_icount =		acm_tty_get_icount,
2004 };
2005 
2006 /*
2007  * Init / exit.
2008  */
2009 
2010 static int __init acm_init(void)
2011 {
2012 	int retval;
2013 	acm_tty_driver = alloc_tty_driver(ACM_TTY_MINORS);
2014 	if (!acm_tty_driver)
2015 		return -ENOMEM;
2016 	acm_tty_driver->driver_name = "acm",
2017 	acm_tty_driver->name = "ttyACM",
2018 	acm_tty_driver->major = ACM_TTY_MAJOR,
2019 	acm_tty_driver->minor_start = 0,
2020 	acm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
2021 	acm_tty_driver->subtype = SERIAL_TYPE_NORMAL,
2022 	acm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
2023 	acm_tty_driver->init_termios = tty_std_termios;
2024 	acm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD |
2025 								HUPCL | CLOCAL;
2026 	tty_set_operations(acm_tty_driver, &acm_ops);
2027 
2028 	retval = tty_register_driver(acm_tty_driver);
2029 	if (retval) {
2030 		put_tty_driver(acm_tty_driver);
2031 		return retval;
2032 	}
2033 
2034 	retval = usb_register(&acm_driver);
2035 	if (retval) {
2036 		tty_unregister_driver(acm_tty_driver);
2037 		put_tty_driver(acm_tty_driver);
2038 		return retval;
2039 	}
2040 
2041 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
2042 
2043 	return 0;
2044 }
2045 
2046 static void __exit acm_exit(void)
2047 {
2048 	usb_deregister(&acm_driver);
2049 	tty_unregister_driver(acm_tty_driver);
2050 	put_tty_driver(acm_tty_driver);
2051 	idr_destroy(&acm_minors);
2052 }
2053 
2054 module_init(acm_init);
2055 module_exit(acm_exit);
2056 
2057 MODULE_AUTHOR(DRIVER_AUTHOR);
2058 MODULE_DESCRIPTION(DRIVER_DESC);
2059 MODULE_LICENSE("GPL");
2060 MODULE_ALIAS_CHARDEV_MAJOR(ACM_TTY_MAJOR);
2061