xref: /linux/drivers/usb/class/cdc-acm.c (revision 4ac6d90867a4de2e12117e755dbd76e08d88697f)
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 
18 #undef DEBUG
19 #undef VERBOSE_DEBUG
20 
21 #include <linux/kernel.h>
22 #include <linux/sched/signal.h>
23 #include <linux/errno.h>
24 #include <linux/init.h>
25 #include <linux/slab.h>
26 #include <linux/log2.h>
27 #include <linux/tty.h>
28 #include <linux/serial.h>
29 #include <linux/tty_driver.h>
30 #include <linux/tty_flip.h>
31 #include <linux/module.h>
32 #include <linux/mutex.h>
33 #include <linux/uaccess.h>
34 #include <linux/usb.h>
35 #include <linux/usb/cdc.h>
36 #include <asm/byteorder.h>
37 #include <asm/unaligned.h>
38 #include <linux/idr.h>
39 #include <linux/list.h>
40 
41 #include "cdc-acm.h"
42 
43 
44 #define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek, Johan Hovold"
45 #define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
46 
47 static struct usb_driver acm_driver;
48 static struct tty_driver *acm_tty_driver;
49 
50 static DEFINE_IDR(acm_minors);
51 static DEFINE_MUTEX(acm_minors_lock);
52 
53 static void acm_tty_set_termios(struct tty_struct *tty,
54 				struct ktermios *termios_old);
55 
56 /*
57  * acm_minors accessors
58  */
59 
60 /*
61  * Look up an ACM structure by minor. If found and not disconnected, increment
62  * its refcount and return it with its mutex held.
63  */
64 static struct acm *acm_get_by_minor(unsigned int minor)
65 {
66 	struct acm *acm;
67 
68 	mutex_lock(&acm_minors_lock);
69 	acm = idr_find(&acm_minors, minor);
70 	if (acm) {
71 		mutex_lock(&acm->mutex);
72 		if (acm->disconnected) {
73 			mutex_unlock(&acm->mutex);
74 			acm = NULL;
75 		} else {
76 			tty_port_get(&acm->port);
77 			mutex_unlock(&acm->mutex);
78 		}
79 	}
80 	mutex_unlock(&acm_minors_lock);
81 	return acm;
82 }
83 
84 /*
85  * Try to find an available minor number and if found, associate it with 'acm'.
86  */
87 static int acm_alloc_minor(struct acm *acm)
88 {
89 	int minor;
90 
91 	mutex_lock(&acm_minors_lock);
92 	minor = idr_alloc(&acm_minors, acm, 0, ACM_TTY_MINORS, GFP_KERNEL);
93 	mutex_unlock(&acm_minors_lock);
94 
95 	return minor;
96 }
97 
98 /* Release the minor number associated with 'acm'.  */
99 static void acm_release_minor(struct acm *acm)
100 {
101 	mutex_lock(&acm_minors_lock);
102 	idr_remove(&acm_minors, acm->minor);
103 	mutex_unlock(&acm_minors_lock);
104 }
105 
106 /*
107  * Functions for ACM control messages.
108  */
109 
110 static int acm_ctrl_msg(struct acm *acm, int request, int value,
111 							void *buf, int len)
112 {
113 	int retval;
114 
115 	retval = usb_autopm_get_interface(acm->control);
116 	if (retval)
117 		return retval;
118 
119 	retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
120 		request, USB_RT_ACM, value,
121 		acm->control->altsetting[0].desc.bInterfaceNumber,
122 		buf, len, 5000);
123 
124 	dev_dbg(&acm->control->dev,
125 		"%s - rq 0x%02x, val %#x, len %#x, result %d\n",
126 		__func__, request, value, len, retval);
127 
128 	usb_autopm_put_interface(acm->control);
129 
130 	return retval < 0 ? retval : 0;
131 }
132 
133 /* devices aren't required to support these requests.
134  * the cdc acm descriptor tells whether they do...
135  */
136 static inline int acm_set_control(struct acm *acm, int control)
137 {
138 	if (acm->quirks & QUIRK_CONTROL_LINE_STATE)
139 		return -EOPNOTSUPP;
140 
141 	return acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE,
142 			control, NULL, 0);
143 }
144 
145 #define acm_set_line(acm, line) \
146 	acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line))
147 #define acm_send_break(acm, ms) \
148 	acm_ctrl_msg(acm, USB_CDC_REQ_SEND_BREAK, ms, NULL, 0)
149 
150 static void acm_poison_urbs(struct acm *acm)
151 {
152 	int i;
153 
154 	usb_poison_urb(acm->ctrlurb);
155 	for (i = 0; i < ACM_NW; i++)
156 		usb_poison_urb(acm->wb[i].urb);
157 	for (i = 0; i < acm->rx_buflimit; i++)
158 		usb_poison_urb(acm->read_urbs[i]);
159 }
160 
161 static void acm_unpoison_urbs(struct acm *acm)
162 {
163 	int i;
164 
165 	for (i = 0; i < acm->rx_buflimit; i++)
166 		usb_unpoison_urb(acm->read_urbs[i]);
167 	for (i = 0; i < ACM_NW; i++)
168 		usb_unpoison_urb(acm->wb[i].urb);
169 	usb_unpoison_urb(acm->ctrlurb);
170 }
171 
172 
173 /*
174  * Write buffer management.
175  * All of these assume proper locks taken by the caller.
176  */
177 
178 static int acm_wb_alloc(struct acm *acm)
179 {
180 	int i, wbn;
181 	struct acm_wb *wb;
182 
183 	wbn = 0;
184 	i = 0;
185 	for (;;) {
186 		wb = &acm->wb[wbn];
187 		if (!wb->use) {
188 			wb->use = true;
189 			wb->len = 0;
190 			return wbn;
191 		}
192 		wbn = (wbn + 1) % ACM_NW;
193 		if (++i >= ACM_NW)
194 			return -1;
195 	}
196 }
197 
198 static int acm_wb_is_avail(struct acm *acm)
199 {
200 	int i, n;
201 	unsigned long flags;
202 
203 	n = ACM_NW;
204 	spin_lock_irqsave(&acm->write_lock, flags);
205 	for (i = 0; i < ACM_NW; i++)
206 		if(acm->wb[i].use)
207 			n--;
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 = false;
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 		if (rc != -EPERM)
242 			dev_err(&acm->data->dev,
243 				"%s - usb_submit_urb(write bulk) failed: %d\n",
244 				__func__, rc);
245 		acm_write_done(acm, wb);
246 	}
247 	return rc;
248 }
249 
250 /*
251  * attributes exported through sysfs
252  */
253 static ssize_t bmCapabilities_show
254 (struct device *dev, struct device_attribute *attr, char *buf)
255 {
256 	struct usb_interface *intf = to_usb_interface(dev);
257 	struct acm *acm = usb_get_intfdata(intf);
258 
259 	return sprintf(buf, "%d", acm->ctrl_caps);
260 }
261 static DEVICE_ATTR_RO(bmCapabilities);
262 
263 static ssize_t wCountryCodes_show
264 (struct device *dev, struct device_attribute *attr, char *buf)
265 {
266 	struct usb_interface *intf = to_usb_interface(dev);
267 	struct acm *acm = usb_get_intfdata(intf);
268 
269 	memcpy(buf, acm->country_codes, acm->country_code_size);
270 	return acm->country_code_size;
271 }
272 
273 static DEVICE_ATTR_RO(wCountryCodes);
274 
275 static ssize_t iCountryCodeRelDate_show
276 (struct device *dev, struct device_attribute *attr, char *buf)
277 {
278 	struct usb_interface *intf = to_usb_interface(dev);
279 	struct acm *acm = usb_get_intfdata(intf);
280 
281 	return sprintf(buf, "%d", acm->country_rel_date);
282 }
283 
284 static DEVICE_ATTR_RO(iCountryCodeRelDate);
285 /*
286  * Interrupt handlers for various ACM device responses
287  */
288 
289 static void acm_process_notification(struct acm *acm, unsigned char *buf)
290 {
291 	int newctrl;
292 	int difference;
293 	unsigned long flags;
294 	struct usb_cdc_notification *dr = (struct usb_cdc_notification *)buf;
295 	unsigned char *data = buf + sizeof(struct usb_cdc_notification);
296 
297 	switch (dr->bNotificationType) {
298 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
299 		dev_dbg(&acm->control->dev,
300 			"%s - network connection: %d\n", __func__, dr->wValue);
301 		break;
302 
303 	case USB_CDC_NOTIFY_SERIAL_STATE:
304 		if (le16_to_cpu(dr->wLength) != 2) {
305 			dev_dbg(&acm->control->dev,
306 				"%s - malformed serial state\n", __func__);
307 			break;
308 		}
309 
310 		newctrl = get_unaligned_le16(data);
311 		dev_dbg(&acm->control->dev,
312 			"%s - serial state: 0x%x\n", __func__, newctrl);
313 
314 		if (!acm->clocal && (acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
315 			dev_dbg(&acm->control->dev,
316 				"%s - calling hangup\n", __func__);
317 			tty_port_tty_hangup(&acm->port, false);
318 		}
319 
320 		difference = acm->ctrlin ^ newctrl;
321 		spin_lock_irqsave(&acm->read_lock, flags);
322 		acm->ctrlin = newctrl;
323 		acm->oldcount = acm->iocount;
324 
325 		if (difference & ACM_CTRL_DSR)
326 			acm->iocount.dsr++;
327 		if (difference & ACM_CTRL_DCD)
328 			acm->iocount.dcd++;
329 		if (newctrl & ACM_CTRL_BRK) {
330 			acm->iocount.brk++;
331 			tty_insert_flip_char(&acm->port, 0, TTY_BREAK);
332 		}
333 		if (newctrl & ACM_CTRL_RI)
334 			acm->iocount.rng++;
335 		if (newctrl & ACM_CTRL_FRAMING)
336 			acm->iocount.frame++;
337 		if (newctrl & ACM_CTRL_PARITY)
338 			acm->iocount.parity++;
339 		if (newctrl & ACM_CTRL_OVERRUN)
340 			acm->iocount.overrun++;
341 		spin_unlock_irqrestore(&acm->read_lock, flags);
342 
343 		if (difference)
344 			wake_up_all(&acm->wioctl);
345 
346 		break;
347 
348 	default:
349 		dev_dbg(&acm->control->dev,
350 			"%s - unknown notification %d received: index %d len %d\n",
351 			__func__,
352 			dr->bNotificationType, dr->wIndex, dr->wLength);
353 	}
354 }
355 
356 /* control interface reports status changes with "interrupt" transfers */
357 static void acm_ctrl_irq(struct urb *urb)
358 {
359 	struct acm *acm = urb->context;
360 	struct usb_cdc_notification *dr = urb->transfer_buffer;
361 	unsigned int current_size = urb->actual_length;
362 	unsigned int expected_size, copy_size, alloc_size;
363 	int retval;
364 	int status = urb->status;
365 
366 	switch (status) {
367 	case 0:
368 		/* success */
369 		break;
370 	case -ECONNRESET:
371 	case -ENOENT:
372 	case -ESHUTDOWN:
373 		/* this urb is terminated, clean up */
374 		dev_dbg(&acm->control->dev,
375 			"%s - urb shutting down with status: %d\n",
376 			__func__, status);
377 		return;
378 	default:
379 		dev_dbg(&acm->control->dev,
380 			"%s - nonzero urb status received: %d\n",
381 			__func__, status);
382 		goto exit;
383 	}
384 
385 	usb_mark_last_busy(acm->dev);
386 
387 	if (acm->nb_index)
388 		dr = (struct usb_cdc_notification *)acm->notification_buffer;
389 
390 	/* size = notification-header + (optional) data */
391 	expected_size = sizeof(struct usb_cdc_notification) +
392 					le16_to_cpu(dr->wLength);
393 
394 	if (current_size < expected_size) {
395 		/* notification is transmitted fragmented, reassemble */
396 		if (acm->nb_size < expected_size) {
397 			u8 *new_buffer;
398 			alloc_size = roundup_pow_of_two(expected_size);
399 			/* Final freeing is done on disconnect. */
400 			new_buffer = krealloc(acm->notification_buffer,
401 					      alloc_size, GFP_ATOMIC);
402 			if (!new_buffer) {
403 				acm->nb_index = 0;
404 				goto exit;
405 			}
406 
407 			acm->notification_buffer = new_buffer;
408 			acm->nb_size = alloc_size;
409 			dr = (struct usb_cdc_notification *)acm->notification_buffer;
410 		}
411 
412 		copy_size = min(current_size,
413 				expected_size - acm->nb_index);
414 
415 		memcpy(&acm->notification_buffer[acm->nb_index],
416 		       urb->transfer_buffer, copy_size);
417 		acm->nb_index += copy_size;
418 		current_size = acm->nb_index;
419 	}
420 
421 	if (current_size >= expected_size) {
422 		/* notification complete */
423 		acm_process_notification(acm, (unsigned char *)dr);
424 		acm->nb_index = 0;
425 	}
426 
427 exit:
428 	retval = usb_submit_urb(urb, GFP_ATOMIC);
429 	if (retval && retval != -EPERM && retval != -ENODEV)
430 		dev_err(&acm->control->dev,
431 			"%s - usb_submit_urb failed: %d\n", __func__, retval);
432 	else
433 		dev_vdbg(&acm->control->dev,
434 			"control resubmission terminated %d\n", retval);
435 }
436 
437 static int acm_submit_read_urb(struct acm *acm, int index, gfp_t mem_flags)
438 {
439 	int res;
440 
441 	if (!test_and_clear_bit(index, &acm->read_urbs_free))
442 		return 0;
443 
444 	res = usb_submit_urb(acm->read_urbs[index], mem_flags);
445 	if (res) {
446 		if (res != -EPERM && res != -ENODEV) {
447 			dev_err(&acm->data->dev,
448 				"urb %d failed submission with %d\n",
449 				index, res);
450 		} else {
451 			dev_vdbg(&acm->data->dev, "intended failure %d\n", res);
452 		}
453 		set_bit(index, &acm->read_urbs_free);
454 		return res;
455 	} else {
456 		dev_vdbg(&acm->data->dev, "submitted urb %d\n", index);
457 	}
458 
459 	return 0;
460 }
461 
462 static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
463 {
464 	int res;
465 	int i;
466 
467 	for (i = 0; i < acm->rx_buflimit; ++i) {
468 		res = acm_submit_read_urb(acm, i, mem_flags);
469 		if (res)
470 			return res;
471 	}
472 
473 	return 0;
474 }
475 
476 static void acm_process_read_urb(struct acm *acm, struct urb *urb)
477 {
478 	if (!urb->actual_length)
479 		return;
480 
481 	tty_insert_flip_string(&acm->port, urb->transfer_buffer,
482 			urb->actual_length);
483 	tty_flip_buffer_push(&acm->port);
484 }
485 
486 static void acm_read_bulk_callback(struct urb *urb)
487 {
488 	struct acm_rb *rb = urb->context;
489 	struct acm *acm = rb->instance;
490 	int status = urb->status;
491 	bool stopped = false;
492 	bool stalled = false;
493 	bool cooldown = false;
494 
495 	dev_vdbg(&acm->data->dev, "got urb %d, len %d, status %d\n",
496 		rb->index, urb->actual_length, status);
497 
498 	switch (status) {
499 	case 0:
500 		usb_mark_last_busy(acm->dev);
501 		acm_process_read_urb(acm, urb);
502 		break;
503 	case -EPIPE:
504 		set_bit(EVENT_RX_STALL, &acm->flags);
505 		stalled = true;
506 		break;
507 	case -ENOENT:
508 	case -ECONNRESET:
509 	case -ESHUTDOWN:
510 		dev_dbg(&acm->data->dev,
511 			"%s - urb shutting down with status: %d\n",
512 			__func__, status);
513 		stopped = true;
514 		break;
515 	case -EOVERFLOW:
516 	case -EPROTO:
517 		dev_dbg(&acm->data->dev,
518 			"%s - cooling babbling device\n", __func__);
519 		usb_mark_last_busy(acm->dev);
520 		set_bit(rb->index, &acm->urbs_in_error_delay);
521 		set_bit(ACM_ERROR_DELAY, &acm->flags);
522 		cooldown = true;
523 		break;
524 	default:
525 		dev_dbg(&acm->data->dev,
526 			"%s - nonzero urb status received: %d\n",
527 			__func__, status);
528 		break;
529 	}
530 
531 	/*
532 	 * Make sure URB processing is done before marking as free to avoid
533 	 * racing with unthrottle() on another CPU. Matches the barriers
534 	 * implied by the test_and_clear_bit() in acm_submit_read_urb().
535 	 */
536 	smp_mb__before_atomic();
537 	set_bit(rb->index, &acm->read_urbs_free);
538 	/*
539 	 * Make sure URB is marked as free before checking the throttled flag
540 	 * to avoid racing with unthrottle() on another CPU. Matches the
541 	 * smp_mb() in unthrottle().
542 	 */
543 	smp_mb__after_atomic();
544 
545 	if (stopped || stalled || cooldown) {
546 		if (stalled)
547 			schedule_delayed_work(&acm->dwork, 0);
548 		else if (cooldown)
549 			schedule_delayed_work(&acm->dwork, HZ / 2);
550 		return;
551 	}
552 
553 	if (test_bit(ACM_THROTTLED, &acm->flags))
554 		return;
555 
556 	acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
557 }
558 
559 /* data interface wrote those outgoing bytes */
560 static void acm_write_bulk(struct urb *urb)
561 {
562 	struct acm_wb *wb = urb->context;
563 	struct acm *acm = wb->instance;
564 	unsigned long flags;
565 	int status = urb->status;
566 
567 	if (status || (urb->actual_length != urb->transfer_buffer_length))
568 		dev_vdbg(&acm->data->dev, "wrote len %d/%d, status %d\n",
569 			urb->actual_length,
570 			urb->transfer_buffer_length,
571 			status);
572 
573 	spin_lock_irqsave(&acm->write_lock, flags);
574 	acm_write_done(acm, wb);
575 	spin_unlock_irqrestore(&acm->write_lock, flags);
576 	set_bit(EVENT_TTY_WAKEUP, &acm->flags);
577 	schedule_delayed_work(&acm->dwork, 0);
578 }
579 
580 static void acm_softint(struct work_struct *work)
581 {
582 	int i;
583 	struct acm *acm = container_of(work, struct acm, dwork.work);
584 
585 	if (test_bit(EVENT_RX_STALL, &acm->flags)) {
586 		smp_mb(); /* against acm_suspend() */
587 		if (!acm->susp_count) {
588 			for (i = 0; i < acm->rx_buflimit; i++)
589 				usb_kill_urb(acm->read_urbs[i]);
590 			usb_clear_halt(acm->dev, acm->in);
591 			acm_submit_read_urbs(acm, GFP_KERNEL);
592 			clear_bit(EVENT_RX_STALL, &acm->flags);
593 		}
594 	}
595 
596 	if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) {
597 		for (i = 0; i < acm->rx_buflimit; i++)
598 			if (test_and_clear_bit(i, &acm->urbs_in_error_delay))
599 				acm_submit_read_urb(acm, i, GFP_KERNEL);
600 	}
601 
602 	if (test_and_clear_bit(EVENT_TTY_WAKEUP, &acm->flags))
603 		tty_port_tty_wakeup(&acm->port);
604 }
605 
606 /*
607  * TTY handlers
608  */
609 
610 static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
611 {
612 	struct acm *acm;
613 	int retval;
614 
615 	acm = acm_get_by_minor(tty->index);
616 	if (!acm)
617 		return -ENODEV;
618 
619 	retval = tty_standard_install(driver, tty);
620 	if (retval)
621 		goto error_init_termios;
622 
623 	/*
624 	 * Suppress initial echoing for some devices which might send data
625 	 * immediately after acm driver has been installed.
626 	 */
627 	if (acm->quirks & DISABLE_ECHO)
628 		tty->termios.c_lflag &= ~ECHO;
629 
630 	tty->driver_data = acm;
631 
632 	return 0;
633 
634 error_init_termios:
635 	tty_port_put(&acm->port);
636 	return retval;
637 }
638 
639 static int acm_tty_open(struct tty_struct *tty, struct file *filp)
640 {
641 	struct acm *acm = tty->driver_data;
642 
643 	return tty_port_open(&acm->port, tty, filp);
644 }
645 
646 static void acm_port_dtr_rts(struct tty_port *port, int raise)
647 {
648 	struct acm *acm = container_of(port, struct acm, port);
649 	int val;
650 	int res;
651 
652 	if (raise)
653 		val = ACM_CTRL_DTR | ACM_CTRL_RTS;
654 	else
655 		val = 0;
656 
657 	/* FIXME: add missing ctrlout locking throughout driver */
658 	acm->ctrlout = val;
659 
660 	res = acm_set_control(acm, val);
661 	if (res && (acm->ctrl_caps & USB_CDC_CAP_LINE))
662 		/* This is broken in too many devices to spam the logs */
663 		dev_dbg(&acm->control->dev, "failed to set dtr/rts\n");
664 }
665 
666 static int acm_port_activate(struct tty_port *port, struct tty_struct *tty)
667 {
668 	struct acm *acm = container_of(port, struct acm, port);
669 	int retval = -ENODEV;
670 	int i;
671 
672 	mutex_lock(&acm->mutex);
673 	if (acm->disconnected)
674 		goto disconnected;
675 
676 	retval = usb_autopm_get_interface(acm->control);
677 	if (retval)
678 		goto error_get_interface;
679 
680 	/*
681 	 * FIXME: Why do we need this? Allocating 64K of physically contiguous
682 	 * memory is really nasty...
683 	 */
684 	set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
685 	acm->control->needs_remote_wakeup = 1;
686 
687 	acm->ctrlurb->dev = acm->dev;
688 	retval = usb_submit_urb(acm->ctrlurb, GFP_KERNEL);
689 	if (retval) {
690 		dev_err(&acm->control->dev,
691 			"%s - usb_submit_urb(ctrl irq) failed\n", __func__);
692 		goto error_submit_urb;
693 	}
694 
695 	acm_tty_set_termios(tty, NULL);
696 
697 	/*
698 	 * Unthrottle device in case the TTY was closed while throttled.
699 	 */
700 	clear_bit(ACM_THROTTLED, &acm->flags);
701 
702 	retval = acm_submit_read_urbs(acm, GFP_KERNEL);
703 	if (retval)
704 		goto error_submit_read_urbs;
705 
706 	usb_autopm_put_interface(acm->control);
707 
708 	mutex_unlock(&acm->mutex);
709 
710 	return 0;
711 
712 error_submit_read_urbs:
713 	for (i = 0; i < acm->rx_buflimit; i++)
714 		usb_kill_urb(acm->read_urbs[i]);
715 	usb_kill_urb(acm->ctrlurb);
716 error_submit_urb:
717 	usb_autopm_put_interface(acm->control);
718 error_get_interface:
719 disconnected:
720 	mutex_unlock(&acm->mutex);
721 
722 	return usb_translate_errors(retval);
723 }
724 
725 static void acm_port_destruct(struct tty_port *port)
726 {
727 	struct acm *acm = container_of(port, struct acm, port);
728 
729 	acm_release_minor(acm);
730 	usb_put_intf(acm->control);
731 	kfree(acm->country_codes);
732 	kfree(acm);
733 }
734 
735 static void acm_port_shutdown(struct tty_port *port)
736 {
737 	struct acm *acm = container_of(port, struct acm, port);
738 	struct urb *urb;
739 	struct acm_wb *wb;
740 
741 	/*
742 	 * Need to grab write_lock to prevent race with resume, but no need to
743 	 * hold it due to the tty-port initialised flag.
744 	 */
745 	acm_poison_urbs(acm);
746 	spin_lock_irq(&acm->write_lock);
747 	spin_unlock_irq(&acm->write_lock);
748 
749 	usb_autopm_get_interface_no_resume(acm->control);
750 	acm->control->needs_remote_wakeup = 0;
751 	usb_autopm_put_interface(acm->control);
752 
753 	for (;;) {
754 		urb = usb_get_from_anchor(&acm->delayed);
755 		if (!urb)
756 			break;
757 		wb = urb->context;
758 		wb->use = false;
759 		usb_autopm_put_interface_async(acm->control);
760 	}
761 
762 	acm_unpoison_urbs(acm);
763 
764 }
765 
766 static void acm_tty_cleanup(struct tty_struct *tty)
767 {
768 	struct acm *acm = tty->driver_data;
769 
770 	tty_port_put(&acm->port);
771 }
772 
773 static void acm_tty_hangup(struct tty_struct *tty)
774 {
775 	struct acm *acm = tty->driver_data;
776 
777 	tty_port_hangup(&acm->port);
778 }
779 
780 static void acm_tty_close(struct tty_struct *tty, struct file *filp)
781 {
782 	struct acm *acm = tty->driver_data;
783 
784 	tty_port_close(&acm->port, tty, filp);
785 }
786 
787 static int acm_tty_write(struct tty_struct *tty,
788 					const unsigned char *buf, int count)
789 {
790 	struct acm *acm = tty->driver_data;
791 	int stat;
792 	unsigned long flags;
793 	int wbn;
794 	struct acm_wb *wb;
795 
796 	if (!count)
797 		return 0;
798 
799 	dev_vdbg(&acm->data->dev, "%d bytes from tty layer\n", count);
800 
801 	spin_lock_irqsave(&acm->write_lock, flags);
802 	wbn = acm_wb_alloc(acm);
803 	if (wbn < 0) {
804 		spin_unlock_irqrestore(&acm->write_lock, flags);
805 		return 0;
806 	}
807 	wb = &acm->wb[wbn];
808 
809 	if (!acm->dev) {
810 		wb->use = false;
811 		spin_unlock_irqrestore(&acm->write_lock, flags);
812 		return -ENODEV;
813 	}
814 
815 	count = (count > acm->writesize) ? acm->writesize : count;
816 	dev_vdbg(&acm->data->dev, "writing %d bytes\n", count);
817 	memcpy(wb->buf, buf, count);
818 	wb->len = count;
819 
820 	stat = usb_autopm_get_interface_async(acm->control);
821 	if (stat) {
822 		wb->use = false;
823 		spin_unlock_irqrestore(&acm->write_lock, flags);
824 		return stat;
825 	}
826 
827 	if (acm->susp_count) {
828 		usb_anchor_urb(wb->urb, &acm->delayed);
829 		spin_unlock_irqrestore(&acm->write_lock, flags);
830 		return count;
831 	}
832 
833 	stat = acm_start_wb(acm, wb);
834 	spin_unlock_irqrestore(&acm->write_lock, flags);
835 
836 	if (stat < 0)
837 		return stat;
838 	return count;
839 }
840 
841 static unsigned int acm_tty_write_room(struct tty_struct *tty)
842 {
843 	struct acm *acm = tty->driver_data;
844 	/*
845 	 * Do not let the line discipline to know that we have a reserve,
846 	 * or it might get too enthusiastic.
847 	 */
848 	return acm_wb_is_avail(acm) ? acm->writesize : 0;
849 }
850 
851 static unsigned int acm_tty_chars_in_buffer(struct tty_struct *tty)
852 {
853 	struct acm *acm = tty->driver_data;
854 	/*
855 	 * if the device was unplugged then any remaining characters fell out
856 	 * of the connector ;)
857 	 */
858 	if (acm->disconnected)
859 		return 0;
860 	/*
861 	 * This is inaccurate (overcounts), but it works.
862 	 */
863 	return (ACM_NW - acm_wb_is_avail(acm)) * acm->writesize;
864 }
865 
866 static void acm_tty_throttle(struct tty_struct *tty)
867 {
868 	struct acm *acm = tty->driver_data;
869 
870 	set_bit(ACM_THROTTLED, &acm->flags);
871 }
872 
873 static void acm_tty_unthrottle(struct tty_struct *tty)
874 {
875 	struct acm *acm = tty->driver_data;
876 
877 	clear_bit(ACM_THROTTLED, &acm->flags);
878 
879 	/* Matches the smp_mb__after_atomic() in acm_read_bulk_callback(). */
880 	smp_mb();
881 
882 	acm_submit_read_urbs(acm, GFP_KERNEL);
883 }
884 
885 static int acm_tty_break_ctl(struct tty_struct *tty, int state)
886 {
887 	struct acm *acm = tty->driver_data;
888 	int retval;
889 
890 	retval = acm_send_break(acm, state ? 0xffff : 0);
891 	if (retval < 0)
892 		dev_dbg(&acm->control->dev,
893 			"%s - send break failed\n", __func__);
894 	return retval;
895 }
896 
897 static int acm_tty_tiocmget(struct tty_struct *tty)
898 {
899 	struct acm *acm = tty->driver_data;
900 
901 	return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
902 	       (acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
903 	       (acm->ctrlin  & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
904 	       (acm->ctrlin  & ACM_CTRL_RI  ? TIOCM_RI  : 0) |
905 	       (acm->ctrlin  & ACM_CTRL_DCD ? TIOCM_CD  : 0) |
906 	       TIOCM_CTS;
907 }
908 
909 static int acm_tty_tiocmset(struct tty_struct *tty,
910 			    unsigned int set, unsigned int clear)
911 {
912 	struct acm *acm = tty->driver_data;
913 	unsigned int newctrl;
914 
915 	newctrl = acm->ctrlout;
916 	set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
917 					(set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
918 	clear = (clear & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
919 					(clear & TIOCM_RTS ? ACM_CTRL_RTS : 0);
920 
921 	newctrl = (newctrl & ~clear) | set;
922 
923 	if (acm->ctrlout == newctrl)
924 		return 0;
925 	return acm_set_control(acm, acm->ctrlout = newctrl);
926 }
927 
928 static int get_serial_info(struct tty_struct *tty, struct serial_struct *ss)
929 {
930 	struct acm *acm = tty->driver_data;
931 
932 	ss->line = acm->minor;
933 	ss->close_delay	= jiffies_to_msecs(acm->port.close_delay) / 10;
934 	ss->closing_wait = acm->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
935 				ASYNC_CLOSING_WAIT_NONE :
936 				jiffies_to_msecs(acm->port.closing_wait) / 10;
937 	return 0;
938 }
939 
940 static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss)
941 {
942 	struct acm *acm = tty->driver_data;
943 	unsigned int closing_wait, close_delay;
944 	int retval = 0;
945 
946 	close_delay = msecs_to_jiffies(ss->close_delay * 10);
947 	closing_wait = ss->closing_wait == ASYNC_CLOSING_WAIT_NONE ?
948 			ASYNC_CLOSING_WAIT_NONE :
949 			msecs_to_jiffies(ss->closing_wait * 10);
950 
951 	mutex_lock(&acm->port.mutex);
952 
953 	if (!capable(CAP_SYS_ADMIN)) {
954 		if ((close_delay != acm->port.close_delay) ||
955 		    (closing_wait != acm->port.closing_wait))
956 			retval = -EPERM;
957 	} else {
958 		acm->port.close_delay  = close_delay;
959 		acm->port.closing_wait = closing_wait;
960 	}
961 
962 	mutex_unlock(&acm->port.mutex);
963 	return retval;
964 }
965 
966 static int wait_serial_change(struct acm *acm, unsigned long arg)
967 {
968 	int rv = 0;
969 	DECLARE_WAITQUEUE(wait, current);
970 	struct async_icount old, new;
971 
972 	do {
973 		spin_lock_irq(&acm->read_lock);
974 		old = acm->oldcount;
975 		new = acm->iocount;
976 		acm->oldcount = new;
977 		spin_unlock_irq(&acm->read_lock);
978 
979 		if ((arg & TIOCM_DSR) &&
980 			old.dsr != new.dsr)
981 			break;
982 		if ((arg & TIOCM_CD)  &&
983 			old.dcd != new.dcd)
984 			break;
985 		if ((arg & TIOCM_RI) &&
986 			old.rng != new.rng)
987 			break;
988 
989 		add_wait_queue(&acm->wioctl, &wait);
990 		set_current_state(TASK_INTERRUPTIBLE);
991 		schedule();
992 		remove_wait_queue(&acm->wioctl, &wait);
993 		if (acm->disconnected) {
994 			if (arg & TIOCM_CD)
995 				break;
996 			else
997 				rv = -ENODEV;
998 		} else {
999 			if (signal_pending(current))
1000 				rv = -ERESTARTSYS;
1001 		}
1002 	} while (!rv);
1003 
1004 
1005 
1006 	return rv;
1007 }
1008 
1009 static int acm_tty_get_icount(struct tty_struct *tty,
1010 					struct serial_icounter_struct *icount)
1011 {
1012 	struct acm *acm = tty->driver_data;
1013 
1014 	icount->dsr = acm->iocount.dsr;
1015 	icount->rng = acm->iocount.rng;
1016 	icount->dcd = acm->iocount.dcd;
1017 	icount->frame = acm->iocount.frame;
1018 	icount->overrun = acm->iocount.overrun;
1019 	icount->parity = acm->iocount.parity;
1020 	icount->brk = acm->iocount.brk;
1021 
1022 	return 0;
1023 }
1024 
1025 static int acm_tty_ioctl(struct tty_struct *tty,
1026 					unsigned int cmd, unsigned long arg)
1027 {
1028 	struct acm *acm = tty->driver_data;
1029 	int rv = -ENOIOCTLCMD;
1030 
1031 	switch (cmd) {
1032 	case TIOCMIWAIT:
1033 		rv = usb_autopm_get_interface(acm->control);
1034 		if (rv < 0) {
1035 			rv = -EIO;
1036 			break;
1037 		}
1038 		rv = wait_serial_change(acm, arg);
1039 		usb_autopm_put_interface(acm->control);
1040 		break;
1041 	}
1042 
1043 	return rv;
1044 }
1045 
1046 static void acm_tty_set_termios(struct tty_struct *tty,
1047 						struct ktermios *termios_old)
1048 {
1049 	struct acm *acm = tty->driver_data;
1050 	struct ktermios *termios = &tty->termios;
1051 	struct usb_cdc_line_coding newline;
1052 	int newctrl = acm->ctrlout;
1053 
1054 	newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
1055 	newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
1056 	newline.bParityType = termios->c_cflag & PARENB ?
1057 				(termios->c_cflag & PARODD ? 1 : 2) +
1058 				(termios->c_cflag & CMSPAR ? 2 : 0) : 0;
1059 	newline.bDataBits = tty_get_char_size(termios->c_cflag);
1060 
1061 	/* FIXME: Needs to clear unsupported bits in the termios */
1062 	acm->clocal = ((termios->c_cflag & CLOCAL) != 0);
1063 
1064 	if (C_BAUD(tty) == B0) {
1065 		newline.dwDTERate = acm->line.dwDTERate;
1066 		newctrl &= ~ACM_CTRL_DTR;
1067 	} else if (termios_old && (termios_old->c_cflag & CBAUD) == B0) {
1068 		newctrl |=  ACM_CTRL_DTR;
1069 	}
1070 
1071 	if (newctrl != acm->ctrlout)
1072 		acm_set_control(acm, acm->ctrlout = newctrl);
1073 
1074 	if (memcmp(&acm->line, &newline, sizeof newline)) {
1075 		memcpy(&acm->line, &newline, sizeof newline);
1076 		dev_dbg(&acm->control->dev, "%s - set line: %d %d %d %d\n",
1077 			__func__,
1078 			le32_to_cpu(newline.dwDTERate),
1079 			newline.bCharFormat, newline.bParityType,
1080 			newline.bDataBits);
1081 		acm_set_line(acm, &acm->line);
1082 	}
1083 }
1084 
1085 static const struct tty_port_operations acm_port_ops = {
1086 	.dtr_rts = acm_port_dtr_rts,
1087 	.shutdown = acm_port_shutdown,
1088 	.activate = acm_port_activate,
1089 	.destruct = acm_port_destruct,
1090 };
1091 
1092 /*
1093  * USB probe and disconnect routines.
1094  */
1095 
1096 /* Little helpers: write/read buffers free */
1097 static void acm_write_buffers_free(struct acm *acm)
1098 {
1099 	int i;
1100 	struct acm_wb *wb;
1101 
1102 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++)
1103 		usb_free_coherent(acm->dev, acm->writesize, wb->buf, wb->dmah);
1104 }
1105 
1106 static void acm_read_buffers_free(struct acm *acm)
1107 {
1108 	int i;
1109 
1110 	for (i = 0; i < acm->rx_buflimit; i++)
1111 		usb_free_coherent(acm->dev, acm->readsize,
1112 			  acm->read_buffers[i].base, acm->read_buffers[i].dma);
1113 }
1114 
1115 /* Little helper: write buffers allocate */
1116 static int acm_write_buffers_alloc(struct acm *acm)
1117 {
1118 	int i;
1119 	struct acm_wb *wb;
1120 
1121 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++) {
1122 		wb->buf = usb_alloc_coherent(acm->dev, acm->writesize, GFP_KERNEL,
1123 		    &wb->dmah);
1124 		if (!wb->buf) {
1125 			while (i != 0) {
1126 				--i;
1127 				--wb;
1128 				usb_free_coherent(acm->dev, acm->writesize,
1129 				    wb->buf, wb->dmah);
1130 			}
1131 			return -ENOMEM;
1132 		}
1133 	}
1134 	return 0;
1135 }
1136 
1137 static int acm_probe(struct usb_interface *intf,
1138 		     const struct usb_device_id *id)
1139 {
1140 	struct usb_cdc_union_desc *union_header = NULL;
1141 	struct usb_cdc_call_mgmt_descriptor *cmgmd = NULL;
1142 	unsigned char *buffer = intf->altsetting->extra;
1143 	int buflen = intf->altsetting->extralen;
1144 	struct usb_interface *control_interface;
1145 	struct usb_interface *data_interface;
1146 	struct usb_endpoint_descriptor *epctrl = NULL;
1147 	struct usb_endpoint_descriptor *epread = NULL;
1148 	struct usb_endpoint_descriptor *epwrite = NULL;
1149 	struct usb_device *usb_dev = interface_to_usbdev(intf);
1150 	struct usb_cdc_parsed_header h;
1151 	struct acm *acm;
1152 	int minor;
1153 	int ctrlsize, readsize;
1154 	u8 *buf;
1155 	int call_intf_num = -1;
1156 	int data_intf_num = -1;
1157 	unsigned long quirks;
1158 	int num_rx_buf;
1159 	int i;
1160 	int combined_interfaces = 0;
1161 	struct device *tty_dev;
1162 	int rv = -ENOMEM;
1163 	int res;
1164 
1165 	/* normal quirks */
1166 	quirks = (unsigned long)id->driver_info;
1167 
1168 	if (quirks == IGNORE_DEVICE)
1169 		return -ENODEV;
1170 
1171 	memset(&h, 0x00, sizeof(struct usb_cdc_parsed_header));
1172 
1173 	num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;
1174 
1175 	/* handle quirks deadly to normal probing*/
1176 	if (quirks == NO_UNION_NORMAL) {
1177 		data_interface = usb_ifnum_to_if(usb_dev, 1);
1178 		control_interface = usb_ifnum_to_if(usb_dev, 0);
1179 		/* we would crash */
1180 		if (!data_interface || !control_interface)
1181 			return -ENODEV;
1182 		goto skip_normal_probe;
1183 	}
1184 
1185 	/* normal probing*/
1186 	if (!buffer) {
1187 		dev_err(&intf->dev, "Weird descriptor references\n");
1188 		return -EINVAL;
1189 	}
1190 
1191 	if (!buflen) {
1192 		if (intf->cur_altsetting->endpoint &&
1193 				intf->cur_altsetting->endpoint->extralen &&
1194 				intf->cur_altsetting->endpoint->extra) {
1195 			dev_dbg(&intf->dev,
1196 				"Seeking extra descriptors on endpoint\n");
1197 			buflen = intf->cur_altsetting->endpoint->extralen;
1198 			buffer = intf->cur_altsetting->endpoint->extra;
1199 		} else {
1200 			dev_err(&intf->dev,
1201 				"Zero length descriptor references\n");
1202 			return -EINVAL;
1203 		}
1204 	}
1205 
1206 	cdc_parse_cdc_header(&h, intf, buffer, buflen);
1207 	union_header = h.usb_cdc_union_desc;
1208 	cmgmd = h.usb_cdc_call_mgmt_descriptor;
1209 	if (cmgmd)
1210 		call_intf_num = cmgmd->bDataInterface;
1211 
1212 	if (!union_header) {
1213 		if (intf->cur_altsetting->desc.bNumEndpoints == 3) {
1214 			dev_dbg(&intf->dev, "No union descriptor, assuming single interface\n");
1215 			combined_interfaces = 1;
1216 			control_interface = data_interface = intf;
1217 			goto look_for_collapsed_interface;
1218 		} else if (call_intf_num > 0) {
1219 			dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n");
1220 			data_intf_num = call_intf_num;
1221 			data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
1222 			control_interface = intf;
1223 		} else {
1224 			dev_dbg(&intf->dev, "No union descriptor, giving up\n");
1225 			return -ENODEV;
1226 		}
1227 	} else {
1228 		int class = -1;
1229 
1230 		data_intf_num = union_header->bSlaveInterface0;
1231 		control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
1232 		data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
1233 
1234 		if (control_interface)
1235 			class = control_interface->cur_altsetting->desc.bInterfaceClass;
1236 
1237 		if (class != USB_CLASS_COMM && class != USB_CLASS_CDC_DATA) {
1238 			dev_dbg(&intf->dev, "Broken union descriptor, assuming single interface\n");
1239 			combined_interfaces = 1;
1240 			control_interface = data_interface = intf;
1241 			goto look_for_collapsed_interface;
1242 		}
1243 	}
1244 
1245 	if (!control_interface || !data_interface) {
1246 		dev_dbg(&intf->dev, "no interfaces\n");
1247 		return -ENODEV;
1248 	}
1249 
1250 	if (data_intf_num != call_intf_num)
1251 		dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");
1252 
1253 	if (control_interface == data_interface) {
1254 		/* some broken devices designed for windows work this way */
1255 		dev_warn(&intf->dev,"Control and data interfaces are not separated!\n");
1256 		combined_interfaces = 1;
1257 		/* a popular other OS doesn't use it */
1258 		quirks |= NO_CAP_LINE;
1259 		if (data_interface->cur_altsetting->desc.bNumEndpoints != 3) {
1260 			dev_err(&intf->dev, "This needs exactly 3 endpoints\n");
1261 			return -EINVAL;
1262 		}
1263 look_for_collapsed_interface:
1264 		res = usb_find_common_endpoints(data_interface->cur_altsetting,
1265 				&epread, &epwrite, &epctrl, NULL);
1266 		if (res)
1267 			return res;
1268 
1269 		goto made_compressed_probe;
1270 	}
1271 
1272 skip_normal_probe:
1273 
1274 	/*workaround for switched interfaces */
1275 	if (data_interface->cur_altsetting->desc.bInterfaceClass != USB_CLASS_CDC_DATA) {
1276 		if (control_interface->cur_altsetting->desc.bInterfaceClass == USB_CLASS_CDC_DATA) {
1277 			dev_dbg(&intf->dev,
1278 				"Your device has switched interfaces.\n");
1279 			swap(control_interface, data_interface);
1280 		} else {
1281 			return -EINVAL;
1282 		}
1283 	}
1284 
1285 	/* Accept probe requests only for the control interface */
1286 	if (!combined_interfaces && intf != control_interface)
1287 		return -ENODEV;
1288 
1289 	if (data_interface->cur_altsetting->desc.bNumEndpoints < 2 ||
1290 	    control_interface->cur_altsetting->desc.bNumEndpoints == 0)
1291 		return -EINVAL;
1292 
1293 	epctrl = &control_interface->cur_altsetting->endpoint[0].desc;
1294 	epread = &data_interface->cur_altsetting->endpoint[0].desc;
1295 	epwrite = &data_interface->cur_altsetting->endpoint[1].desc;
1296 
1297 
1298 	/* workaround for switched endpoints */
1299 	if (!usb_endpoint_dir_in(epread)) {
1300 		/* descriptors are swapped */
1301 		dev_dbg(&intf->dev,
1302 			"The data interface has switched endpoints\n");
1303 		swap(epread, epwrite);
1304 	}
1305 made_compressed_probe:
1306 	dev_dbg(&intf->dev, "interfaces are valid\n");
1307 
1308 	acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
1309 	if (!acm)
1310 		return -ENOMEM;
1311 
1312 	tty_port_init(&acm->port);
1313 	acm->port.ops = &acm_port_ops;
1314 
1315 	ctrlsize = usb_endpoint_maxp(epctrl);
1316 	readsize = usb_endpoint_maxp(epread) *
1317 				(quirks == SINGLE_RX_URB ? 1 : 2);
1318 	acm->combined_interfaces = combined_interfaces;
1319 	acm->writesize = usb_endpoint_maxp(epwrite) * 20;
1320 	acm->control = control_interface;
1321 	acm->data = data_interface;
1322 
1323 	usb_get_intf(acm->control); /* undone in destruct() */
1324 
1325 	minor = acm_alloc_minor(acm);
1326 	if (minor < 0)
1327 		goto err_put_port;
1328 
1329 	acm->minor = minor;
1330 	acm->dev = usb_dev;
1331 	if (h.usb_cdc_acm_descriptor)
1332 		acm->ctrl_caps = h.usb_cdc_acm_descriptor->bmCapabilities;
1333 	if (quirks & NO_CAP_LINE)
1334 		acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
1335 	acm->ctrlsize = ctrlsize;
1336 	acm->readsize = readsize;
1337 	acm->rx_buflimit = num_rx_buf;
1338 	INIT_DELAYED_WORK(&acm->dwork, acm_softint);
1339 	init_waitqueue_head(&acm->wioctl);
1340 	spin_lock_init(&acm->write_lock);
1341 	spin_lock_init(&acm->read_lock);
1342 	mutex_init(&acm->mutex);
1343 	if (usb_endpoint_xfer_int(epread)) {
1344 		acm->bInterval = epread->bInterval;
1345 		acm->in = usb_rcvintpipe(usb_dev, epread->bEndpointAddress);
1346 	} else {
1347 		acm->in = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
1348 	}
1349 	if (usb_endpoint_xfer_int(epwrite))
1350 		acm->out = usb_sndintpipe(usb_dev, epwrite->bEndpointAddress);
1351 	else
1352 		acm->out = usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress);
1353 	init_usb_anchor(&acm->delayed);
1354 	acm->quirks = quirks;
1355 
1356 	buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
1357 	if (!buf)
1358 		goto err_put_port;
1359 	acm->ctrl_buffer = buf;
1360 
1361 	if (acm_write_buffers_alloc(acm) < 0)
1362 		goto err_free_ctrl_buffer;
1363 
1364 	acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
1365 	if (!acm->ctrlurb)
1366 		goto err_free_write_buffers;
1367 
1368 	for (i = 0; i < num_rx_buf; i++) {
1369 		struct acm_rb *rb = &(acm->read_buffers[i]);
1370 		struct urb *urb;
1371 
1372 		rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
1373 								&rb->dma);
1374 		if (!rb->base)
1375 			goto err_free_read_urbs;
1376 		rb->index = i;
1377 		rb->instance = acm;
1378 
1379 		urb = usb_alloc_urb(0, GFP_KERNEL);
1380 		if (!urb)
1381 			goto err_free_read_urbs;
1382 
1383 		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1384 		urb->transfer_dma = rb->dma;
1385 		if (usb_endpoint_xfer_int(epread))
1386 			usb_fill_int_urb(urb, acm->dev, acm->in, rb->base,
1387 					 acm->readsize,
1388 					 acm_read_bulk_callback, rb,
1389 					 acm->bInterval);
1390 		else
1391 			usb_fill_bulk_urb(urb, acm->dev, acm->in, rb->base,
1392 					  acm->readsize,
1393 					  acm_read_bulk_callback, rb);
1394 
1395 		acm->read_urbs[i] = urb;
1396 		__set_bit(i, &acm->read_urbs_free);
1397 	}
1398 	for (i = 0; i < ACM_NW; i++) {
1399 		struct acm_wb *snd = &(acm->wb[i]);
1400 
1401 		snd->urb = usb_alloc_urb(0, GFP_KERNEL);
1402 		if (!snd->urb)
1403 			goto err_free_write_urbs;
1404 
1405 		if (usb_endpoint_xfer_int(epwrite))
1406 			usb_fill_int_urb(snd->urb, usb_dev, acm->out,
1407 				NULL, acm->writesize, acm_write_bulk, snd, epwrite->bInterval);
1408 		else
1409 			usb_fill_bulk_urb(snd->urb, usb_dev, acm->out,
1410 				NULL, acm->writesize, acm_write_bulk, snd);
1411 		snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1412 		if (quirks & SEND_ZERO_PACKET)
1413 			snd->urb->transfer_flags |= URB_ZERO_PACKET;
1414 		snd->instance = acm;
1415 	}
1416 
1417 	usb_set_intfdata(intf, acm);
1418 
1419 	i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
1420 	if (i < 0)
1421 		goto err_free_write_urbs;
1422 
1423 	if (h.usb_cdc_country_functional_desc) { /* export the country data */
1424 		struct usb_cdc_country_functional_desc * cfd =
1425 					h.usb_cdc_country_functional_desc;
1426 
1427 		acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
1428 		if (!acm->country_codes)
1429 			goto skip_countries;
1430 		acm->country_code_size = cfd->bLength - 4;
1431 		memcpy(acm->country_codes, (u8 *)&cfd->wCountyCode0,
1432 							cfd->bLength - 4);
1433 		acm->country_rel_date = cfd->iCountryCodeRelDate;
1434 
1435 		i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
1436 		if (i < 0) {
1437 			kfree(acm->country_codes);
1438 			acm->country_codes = NULL;
1439 			acm->country_code_size = 0;
1440 			goto skip_countries;
1441 		}
1442 
1443 		i = device_create_file(&intf->dev,
1444 						&dev_attr_iCountryCodeRelDate);
1445 		if (i < 0) {
1446 			device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
1447 			kfree(acm->country_codes);
1448 			acm->country_codes = NULL;
1449 			acm->country_code_size = 0;
1450 			goto skip_countries;
1451 		}
1452 	}
1453 
1454 skip_countries:
1455 	usb_fill_int_urb(acm->ctrlurb, usb_dev,
1456 			 usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
1457 			 acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
1458 			 /* works around buggy devices */
1459 			 epctrl->bInterval ? epctrl->bInterval : 16);
1460 	acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1461 	acm->ctrlurb->transfer_dma = acm->ctrl_dma;
1462 	acm->notification_buffer = NULL;
1463 	acm->nb_index = 0;
1464 	acm->nb_size = 0;
1465 
1466 	acm->line.dwDTERate = cpu_to_le32(9600);
1467 	acm->line.bDataBits = 8;
1468 	acm_set_line(acm, &acm->line);
1469 
1470 	if (!acm->combined_interfaces) {
1471 		rv = usb_driver_claim_interface(&acm_driver, data_interface, acm);
1472 		if (rv)
1473 			goto err_remove_files;
1474 	}
1475 
1476 	tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
1477 			&control_interface->dev);
1478 	if (IS_ERR(tty_dev)) {
1479 		rv = PTR_ERR(tty_dev);
1480 		goto err_release_data_interface;
1481 	}
1482 
1483 	if (quirks & CLEAR_HALT_CONDITIONS) {
1484 		usb_clear_halt(usb_dev, acm->in);
1485 		usb_clear_halt(usb_dev, acm->out);
1486 	}
1487 
1488 	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
1489 
1490 	return 0;
1491 
1492 err_release_data_interface:
1493 	if (!acm->combined_interfaces) {
1494 		/* Clear driver data so that disconnect() returns early. */
1495 		usb_set_intfdata(data_interface, NULL);
1496 		usb_driver_release_interface(&acm_driver, data_interface);
1497 	}
1498 err_remove_files:
1499 	if (acm->country_codes) {
1500 		device_remove_file(&acm->control->dev,
1501 				&dev_attr_wCountryCodes);
1502 		device_remove_file(&acm->control->dev,
1503 				&dev_attr_iCountryCodeRelDate);
1504 	}
1505 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1506 err_free_write_urbs:
1507 	for (i = 0; i < ACM_NW; i++)
1508 		usb_free_urb(acm->wb[i].urb);
1509 err_free_read_urbs:
1510 	for (i = 0; i < num_rx_buf; i++)
1511 		usb_free_urb(acm->read_urbs[i]);
1512 	acm_read_buffers_free(acm);
1513 	usb_free_urb(acm->ctrlurb);
1514 err_free_write_buffers:
1515 	acm_write_buffers_free(acm);
1516 err_free_ctrl_buffer:
1517 	usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1518 err_put_port:
1519 	tty_port_put(&acm->port);
1520 
1521 	return rv;
1522 }
1523 
1524 static void acm_disconnect(struct usb_interface *intf)
1525 {
1526 	struct acm *acm = usb_get_intfdata(intf);
1527 	struct tty_struct *tty;
1528 	int i;
1529 
1530 	/* sibling interface is already cleaning up */
1531 	if (!acm)
1532 		return;
1533 
1534 	acm->disconnected = true;
1535 	/*
1536 	 * there is a circular dependency. acm_softint() can resubmit
1537 	 * the URBs in error handling so we need to block any
1538 	 * submission right away
1539 	 */
1540 	acm_poison_urbs(acm);
1541 	mutex_lock(&acm->mutex);
1542 	if (acm->country_codes) {
1543 		device_remove_file(&acm->control->dev,
1544 				&dev_attr_wCountryCodes);
1545 		device_remove_file(&acm->control->dev,
1546 				&dev_attr_iCountryCodeRelDate);
1547 	}
1548 	wake_up_all(&acm->wioctl);
1549 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1550 	usb_set_intfdata(acm->control, NULL);
1551 	usb_set_intfdata(acm->data, NULL);
1552 	mutex_unlock(&acm->mutex);
1553 
1554 	tty = tty_port_tty_get(&acm->port);
1555 	if (tty) {
1556 		tty_vhangup(tty);
1557 		tty_kref_put(tty);
1558 	}
1559 
1560 	cancel_delayed_work_sync(&acm->dwork);
1561 
1562 	tty_unregister_device(acm_tty_driver, acm->minor);
1563 
1564 	usb_free_urb(acm->ctrlurb);
1565 	for (i = 0; i < ACM_NW; i++)
1566 		usb_free_urb(acm->wb[i].urb);
1567 	for (i = 0; i < acm->rx_buflimit; i++)
1568 		usb_free_urb(acm->read_urbs[i]);
1569 	acm_write_buffers_free(acm);
1570 	usb_free_coherent(acm->dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1571 	acm_read_buffers_free(acm);
1572 
1573 	kfree(acm->notification_buffer);
1574 
1575 	if (!acm->combined_interfaces)
1576 		usb_driver_release_interface(&acm_driver, intf == acm->control ?
1577 					acm->data : acm->control);
1578 
1579 	tty_port_put(&acm->port);
1580 }
1581 
1582 #ifdef CONFIG_PM
1583 static int acm_suspend(struct usb_interface *intf, pm_message_t message)
1584 {
1585 	struct acm *acm = usb_get_intfdata(intf);
1586 	int cnt;
1587 
1588 	spin_lock_irq(&acm->write_lock);
1589 	if (PMSG_IS_AUTO(message)) {
1590 		if (acm->transmitting) {
1591 			spin_unlock_irq(&acm->write_lock);
1592 			return -EBUSY;
1593 		}
1594 	}
1595 	cnt = acm->susp_count++;
1596 	spin_unlock_irq(&acm->write_lock);
1597 
1598 	if (cnt)
1599 		return 0;
1600 
1601 	acm_poison_urbs(acm);
1602 	cancel_delayed_work_sync(&acm->dwork);
1603 	acm->urbs_in_error_delay = 0;
1604 
1605 	return 0;
1606 }
1607 
1608 static int acm_resume(struct usb_interface *intf)
1609 {
1610 	struct acm *acm = usb_get_intfdata(intf);
1611 	struct urb *urb;
1612 	int rv = 0;
1613 
1614 	spin_lock_irq(&acm->write_lock);
1615 
1616 	if (--acm->susp_count)
1617 		goto out;
1618 
1619 	acm_unpoison_urbs(acm);
1620 
1621 	if (tty_port_initialized(&acm->port)) {
1622 		rv = usb_submit_urb(acm->ctrlurb, GFP_ATOMIC);
1623 
1624 		for (;;) {
1625 			urb = usb_get_from_anchor(&acm->delayed);
1626 			if (!urb)
1627 				break;
1628 
1629 			acm_start_wb(acm, urb->context);
1630 		}
1631 
1632 		/*
1633 		 * delayed error checking because we must
1634 		 * do the write path at all cost
1635 		 */
1636 		if (rv < 0)
1637 			goto out;
1638 
1639 		rv = acm_submit_read_urbs(acm, GFP_ATOMIC);
1640 	}
1641 out:
1642 	spin_unlock_irq(&acm->write_lock);
1643 
1644 	return rv;
1645 }
1646 
1647 static int acm_reset_resume(struct usb_interface *intf)
1648 {
1649 	struct acm *acm = usb_get_intfdata(intf);
1650 
1651 	if (tty_port_initialized(&acm->port))
1652 		tty_port_tty_hangup(&acm->port, false);
1653 
1654 	return acm_resume(intf);
1655 }
1656 
1657 #endif /* CONFIG_PM */
1658 
1659 static int acm_pre_reset(struct usb_interface *intf)
1660 {
1661 	struct acm *acm = usb_get_intfdata(intf);
1662 
1663 	clear_bit(EVENT_RX_STALL, &acm->flags);
1664 	acm->nb_index = 0; /* pending control transfers are lost */
1665 
1666 	return 0;
1667 }
1668 
1669 #define NOKIA_PCSUITE_ACM_INFO(x) \
1670 		USB_DEVICE_AND_INTERFACE_INFO(0x0421, x, \
1671 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1672 		USB_CDC_ACM_PROTO_VENDOR)
1673 
1674 #define SAMSUNG_PCSUITE_ACM_INFO(x) \
1675 		USB_DEVICE_AND_INTERFACE_INFO(0x04e7, x, \
1676 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1677 		USB_CDC_ACM_PROTO_VENDOR)
1678 
1679 /*
1680  * USB driver structure.
1681  */
1682 
1683 static const struct usb_device_id acm_ids[] = {
1684 	/* quirky and broken devices */
1685 	{ USB_DEVICE(0x0424, 0x274e), /* Microchip Technology, Inc. (formerly SMSC) */
1686 	  .driver_info = DISABLE_ECHO, }, /* DISABLE ECHO in termios flag */
1687 	{ USB_DEVICE(0x076d, 0x0006), /* Denso Cradle CU-321 */
1688 	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
1689 	{ USB_DEVICE(0x17ef, 0x7000), /* Lenovo USB modem */
1690 	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
1691 	{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
1692 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1693 	},
1694 	{ USB_DEVICE(0x045b, 0x023c),	/* Renesas USB Download mode */
1695 	.driver_info = DISABLE_ECHO,	/* Don't echo banner */
1696 	},
1697 	{ USB_DEVICE(0x045b, 0x0248),	/* Renesas USB Download mode */
1698 	.driver_info = DISABLE_ECHO,	/* Don't echo banner */
1699 	},
1700 	{ USB_DEVICE(0x045b, 0x024D),	/* Renesas USB Download mode */
1701 	.driver_info = DISABLE_ECHO,	/* Don't echo banner */
1702 	},
1703 	{ USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; andrey.arapov@gmail.com */
1704 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1705 	},
1706 	{ USB_DEVICE(0x0e8d, 0x2000), /* MediaTek Inc Preloader */
1707 	.driver_info = DISABLE_ECHO, /* DISABLE ECHO in termios flag */
1708 	},
1709 	{ USB_DEVICE(0x0e8d, 0x3329), /* MediaTek Inc GPS */
1710 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1711 	},
1712 	{ USB_DEVICE(0x0482, 0x0203), /* KYOCERA AH-K3001V */
1713 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1714 	},
1715 	{ USB_DEVICE(0x079b, 0x000f), /* BT On-Air USB MODEM */
1716 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1717 	},
1718 	{ USB_DEVICE(0x0ace, 0x1602), /* ZyDAS 56K USB MODEM */
1719 	.driver_info = SINGLE_RX_URB,
1720 	},
1721 	{ USB_DEVICE(0x0ace, 0x1608), /* ZyDAS 56K USB MODEM */
1722 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1723 	},
1724 	{ USB_DEVICE(0x0ace, 0x1611), /* ZyDAS 56K USB MODEM - new version */
1725 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1726 	},
1727 	{ USB_DEVICE(0x11ca, 0x0201), /* VeriFone Mx870 Gadget Serial */
1728 	.driver_info = SINGLE_RX_URB,
1729 	},
1730 	{ USB_DEVICE(0x1965, 0x0018), /* Uniden UBC125XLT */
1731 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1732 	},
1733 	{ USB_DEVICE(0x22b8, 0x7000), /* Motorola Q Phone */
1734 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1735 	},
1736 	{ USB_DEVICE(0x0803, 0x3095), /* Zoom Telephonics Model 3095F USB MODEM */
1737 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1738 	},
1739 	{ USB_DEVICE(0x0572, 0x1321), /* Conexant USB MODEM CX93010 */
1740 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1741 	},
1742 	{ USB_DEVICE(0x0572, 0x1324), /* Conexant USB MODEM RD02-D400 */
1743 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1744 	},
1745 	{ USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */
1746 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1747 	},
1748 	{ USB_DEVICE(0x0572, 0x1349), /* Hiro (Conexant) USB MODEM H50228 */
1749 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1750 	},
1751 	{ USB_DEVICE(0x20df, 0x0001), /* Simtec Electronics Entropy Key */
1752 	.driver_info = QUIRK_CONTROL_LINE_STATE, },
1753 	{ USB_DEVICE(0x2184, 0x001c) },	/* GW Instek AFG-2225 */
1754 	{ USB_DEVICE(0x2184, 0x0036) },	/* GW Instek AFG-125 */
1755 	{ USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
1756 	},
1757 	/* Motorola H24 HSPA module: */
1758 	{ USB_DEVICE(0x22b8, 0x2d91) }, /* modem                                */
1759 	{ USB_DEVICE(0x22b8, 0x2d92),   /* modem           + diagnostics        */
1760 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1761 	},
1762 	{ USB_DEVICE(0x22b8, 0x2d93),   /* modem + AT port                      */
1763 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1764 	},
1765 	{ USB_DEVICE(0x22b8, 0x2d95),   /* modem + AT port + diagnostics        */
1766 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1767 	},
1768 	{ USB_DEVICE(0x22b8, 0x2d96),   /* modem                         + NMEA */
1769 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1770 	},
1771 	{ USB_DEVICE(0x22b8, 0x2d97),   /* modem           + diagnostics + NMEA */
1772 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1773 	},
1774 	{ USB_DEVICE(0x22b8, 0x2d99),   /* modem + AT port               + NMEA */
1775 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1776 	},
1777 	{ USB_DEVICE(0x22b8, 0x2d9a),   /* modem + AT port + diagnostics + NMEA */
1778 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1779 	},
1780 
1781 	{ USB_DEVICE(0x0572, 0x1329), /* Hummingbird huc56s (Conexant) */
1782 	.driver_info = NO_UNION_NORMAL, /* union descriptor misplaced on
1783 					   data interface instead of
1784 					   communications interface.
1785 					   Maybe we should define a new
1786 					   quirk for this. */
1787 	},
1788 	{ USB_DEVICE(0x0572, 0x1340), /* Conexant CX93010-2x UCMxx */
1789 	.driver_info = NO_UNION_NORMAL,
1790 	},
1791 	{ USB_DEVICE(0x05f9, 0x4002), /* PSC Scanning, Magellan 800i */
1792 	.driver_info = NO_UNION_NORMAL,
1793 	},
1794 	{ USB_DEVICE(0x1bbb, 0x0003), /* Alcatel OT-I650 */
1795 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1796 	},
1797 	{ USB_DEVICE(0x1576, 0x03b1), /* Maretron USB100 */
1798 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1799 	},
1800 	{ USB_DEVICE(0xfff0, 0x0100), /* DATECS FP-2000 */
1801 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1802 	},
1803 	{ USB_DEVICE(0x09d8, 0x0320), /* Elatec GmbH TWN3 */
1804 	.driver_info = NO_UNION_NORMAL, /* has misplaced union descriptor */
1805 	},
1806 	{ USB_DEVICE(0x0ca6, 0xa050), /* Castles VEGA3000 */
1807 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1808 	},
1809 
1810 	{ USB_DEVICE(0x2912, 0x0001), /* ATOL FPrint */
1811 	.driver_info = CLEAR_HALT_CONDITIONS,
1812 	},
1813 
1814 	/* Nokia S60 phones expose two ACM channels. The first is
1815 	 * a modem and is picked up by the standard AT-command
1816 	 * information below. The second is 'vendor-specific' but
1817 	 * is treated as a serial device at the S60 end, so we want
1818 	 * to expose it on Linux too. */
1819 	{ NOKIA_PCSUITE_ACM_INFO(0x042D), }, /* Nokia 3250 */
1820 	{ NOKIA_PCSUITE_ACM_INFO(0x04D8), }, /* Nokia 5500 Sport */
1821 	{ NOKIA_PCSUITE_ACM_INFO(0x04C9), }, /* Nokia E50 */
1822 	{ NOKIA_PCSUITE_ACM_INFO(0x0419), }, /* Nokia E60 */
1823 	{ NOKIA_PCSUITE_ACM_INFO(0x044D), }, /* Nokia E61 */
1824 	{ NOKIA_PCSUITE_ACM_INFO(0x0001), }, /* Nokia E61i */
1825 	{ NOKIA_PCSUITE_ACM_INFO(0x0475), }, /* Nokia E62 */
1826 	{ NOKIA_PCSUITE_ACM_INFO(0x0508), }, /* Nokia E65 */
1827 	{ NOKIA_PCSUITE_ACM_INFO(0x0418), }, /* Nokia E70 */
1828 	{ NOKIA_PCSUITE_ACM_INFO(0x0425), }, /* Nokia N71 */
1829 	{ NOKIA_PCSUITE_ACM_INFO(0x0486), }, /* Nokia N73 */
1830 	{ NOKIA_PCSUITE_ACM_INFO(0x04DF), }, /* Nokia N75 */
1831 	{ NOKIA_PCSUITE_ACM_INFO(0x000e), }, /* Nokia N77 */
1832 	{ NOKIA_PCSUITE_ACM_INFO(0x0445), }, /* Nokia N80 */
1833 	{ NOKIA_PCSUITE_ACM_INFO(0x042F), }, /* Nokia N91 & N91 8GB */
1834 	{ NOKIA_PCSUITE_ACM_INFO(0x048E), }, /* Nokia N92 */
1835 	{ NOKIA_PCSUITE_ACM_INFO(0x0420), }, /* Nokia N93 */
1836 	{ NOKIA_PCSUITE_ACM_INFO(0x04E6), }, /* Nokia N93i  */
1837 	{ NOKIA_PCSUITE_ACM_INFO(0x04B2), }, /* Nokia 5700 XpressMusic */
1838 	{ NOKIA_PCSUITE_ACM_INFO(0x0134), }, /* Nokia 6110 Navigator (China) */
1839 	{ NOKIA_PCSUITE_ACM_INFO(0x046E), }, /* Nokia 6110 Navigator */
1840 	{ NOKIA_PCSUITE_ACM_INFO(0x002f), }, /* Nokia 6120 classic &  */
1841 	{ NOKIA_PCSUITE_ACM_INFO(0x0088), }, /* Nokia 6121 classic */
1842 	{ NOKIA_PCSUITE_ACM_INFO(0x00fc), }, /* Nokia 6124 classic */
1843 	{ NOKIA_PCSUITE_ACM_INFO(0x0042), }, /* Nokia E51 */
1844 	{ NOKIA_PCSUITE_ACM_INFO(0x00b0), }, /* Nokia E66 */
1845 	{ NOKIA_PCSUITE_ACM_INFO(0x00ab), }, /* Nokia E71 */
1846 	{ NOKIA_PCSUITE_ACM_INFO(0x0481), }, /* Nokia N76 */
1847 	{ NOKIA_PCSUITE_ACM_INFO(0x0007), }, /* Nokia N81 & N81 8GB */
1848 	{ NOKIA_PCSUITE_ACM_INFO(0x0071), }, /* Nokia N82 */
1849 	{ NOKIA_PCSUITE_ACM_INFO(0x04F0), }, /* Nokia N95 & N95-3 NAM */
1850 	{ NOKIA_PCSUITE_ACM_INFO(0x0070), }, /* Nokia N95 8GB  */
1851 	{ NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1852 	{ NOKIA_PCSUITE_ACM_INFO(0x0099), }, /* Nokia 6210 Navigator, RM-367 */
1853 	{ NOKIA_PCSUITE_ACM_INFO(0x0128), }, /* Nokia 6210 Navigator, RM-419 */
1854 	{ NOKIA_PCSUITE_ACM_INFO(0x008f), }, /* Nokia 6220 Classic */
1855 	{ NOKIA_PCSUITE_ACM_INFO(0x00a0), }, /* Nokia 6650 */
1856 	{ NOKIA_PCSUITE_ACM_INFO(0x007b), }, /* Nokia N78 */
1857 	{ NOKIA_PCSUITE_ACM_INFO(0x0094), }, /* Nokia N85 */
1858 	{ NOKIA_PCSUITE_ACM_INFO(0x003a), }, /* Nokia N96 & N96-3  */
1859 	{ NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1860 	{ NOKIA_PCSUITE_ACM_INFO(0x0108), }, /* Nokia 5320 XpressMusic 2G */
1861 	{ NOKIA_PCSUITE_ACM_INFO(0x01f5), }, /* Nokia N97, RM-505 */
1862 	{ NOKIA_PCSUITE_ACM_INFO(0x02e3), }, /* Nokia 5230, RM-588 */
1863 	{ NOKIA_PCSUITE_ACM_INFO(0x0178), }, /* Nokia E63 */
1864 	{ NOKIA_PCSUITE_ACM_INFO(0x010e), }, /* Nokia E75 */
1865 	{ NOKIA_PCSUITE_ACM_INFO(0x02d9), }, /* Nokia 6760 Slide */
1866 	{ NOKIA_PCSUITE_ACM_INFO(0x01d0), }, /* Nokia E52 */
1867 	{ NOKIA_PCSUITE_ACM_INFO(0x0223), }, /* Nokia E72 */
1868 	{ NOKIA_PCSUITE_ACM_INFO(0x0275), }, /* Nokia X6 */
1869 	{ NOKIA_PCSUITE_ACM_INFO(0x026c), }, /* Nokia N97 Mini */
1870 	{ NOKIA_PCSUITE_ACM_INFO(0x0154), }, /* Nokia 5800 XpressMusic */
1871 	{ NOKIA_PCSUITE_ACM_INFO(0x04ce), }, /* Nokia E90 */
1872 	{ NOKIA_PCSUITE_ACM_INFO(0x01d4), }, /* Nokia E55 */
1873 	{ NOKIA_PCSUITE_ACM_INFO(0x0302), }, /* Nokia N8 */
1874 	{ NOKIA_PCSUITE_ACM_INFO(0x0335), }, /* Nokia E7 */
1875 	{ NOKIA_PCSUITE_ACM_INFO(0x03cd), }, /* Nokia C7 */
1876 	{ SAMSUNG_PCSUITE_ACM_INFO(0x6651), }, /* Samsung GTi8510 (INNOV8) */
1877 
1878 	/* Support for Owen devices */
1879 	{ USB_DEVICE(0x03eb, 0x0030), }, /* Owen SI30 */
1880 
1881 	/* NOTE: non-Nokia COMM/ACM/0xff is likely MSFT RNDIS... NOT a modem! */
1882 
1883 #if IS_ENABLED(CONFIG_INPUT_IMS_PCU)
1884 	{ USB_DEVICE(0x04d8, 0x0082),	/* Application mode */
1885 	.driver_info = IGNORE_DEVICE,
1886 	},
1887 	{ USB_DEVICE(0x04d8, 0x0083),	/* Bootloader mode */
1888 	.driver_info = IGNORE_DEVICE,
1889 	},
1890 #endif
1891 
1892 #if IS_ENABLED(CONFIG_IR_TOY)
1893 	{ USB_DEVICE(0x04d8, 0xfd08),
1894 	.driver_info = IGNORE_DEVICE,
1895 	},
1896 
1897 	{ USB_DEVICE(0x04d8, 0xf58b),
1898 	.driver_info = IGNORE_DEVICE,
1899 	},
1900 #endif
1901 
1902 #if IS_ENABLED(CONFIG_USB_SERIAL_XR)
1903 	{ USB_DEVICE(0x04e2, 0x1400), .driver_info = IGNORE_DEVICE },
1904 	{ USB_DEVICE(0x04e2, 0x1401), .driver_info = IGNORE_DEVICE },
1905 	{ USB_DEVICE(0x04e2, 0x1402), .driver_info = IGNORE_DEVICE },
1906 	{ USB_DEVICE(0x04e2, 0x1403), .driver_info = IGNORE_DEVICE },
1907 	{ USB_DEVICE(0x04e2, 0x1410), .driver_info = IGNORE_DEVICE },
1908 	{ USB_DEVICE(0x04e2, 0x1411), .driver_info = IGNORE_DEVICE },
1909 	{ USB_DEVICE(0x04e2, 0x1412), .driver_info = IGNORE_DEVICE },
1910 	{ USB_DEVICE(0x04e2, 0x1414), .driver_info = IGNORE_DEVICE },
1911 	{ USB_DEVICE(0x04e2, 0x1420), .driver_info = IGNORE_DEVICE },
1912 	{ USB_DEVICE(0x04e2, 0x1422), .driver_info = IGNORE_DEVICE },
1913 	{ USB_DEVICE(0x04e2, 0x1424), .driver_info = IGNORE_DEVICE },
1914 #endif
1915 
1916 	/*Samsung phone in firmware update mode */
1917 	{ USB_DEVICE(0x04e8, 0x685d),
1918 	.driver_info = IGNORE_DEVICE,
1919 	},
1920 
1921 	/* Exclude Infineon Flash Loader utility */
1922 	{ USB_DEVICE(0x058b, 0x0041),
1923 	.driver_info = IGNORE_DEVICE,
1924 	},
1925 
1926 	/* Exclude ETAS ES58x */
1927 	{ USB_DEVICE(0x108c, 0x0159), /* ES581.4 */
1928 	.driver_info = IGNORE_DEVICE,
1929 	},
1930 	{ USB_DEVICE(0x108c, 0x0168), /* ES582.1 */
1931 	.driver_info = IGNORE_DEVICE,
1932 	},
1933 	{ USB_DEVICE(0x108c, 0x0169), /* ES584.1 */
1934 	.driver_info = IGNORE_DEVICE,
1935 	},
1936 
1937 	{ USB_DEVICE(0x1bc7, 0x0021), /* Telit 3G ACM only composition */
1938 	.driver_info = SEND_ZERO_PACKET,
1939 	},
1940 	{ USB_DEVICE(0x1bc7, 0x0023), /* Telit 3G ACM + ECM composition */
1941 	.driver_info = SEND_ZERO_PACKET,
1942 	},
1943 
1944 	/* Exclude Goodix Fingerprint Reader */
1945 	{ USB_DEVICE(0x27c6, 0x5395),
1946 	.driver_info = IGNORE_DEVICE,
1947 	},
1948 
1949 	/* Exclude Heimann Sensor GmbH USB appset demo */
1950 	{ USB_DEVICE(0x32a7, 0x0000),
1951 	.driver_info = IGNORE_DEVICE,
1952 	},
1953 
1954 	/* control interfaces without any protocol set */
1955 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1956 		USB_CDC_PROTO_NONE) },
1957 
1958 	/* control interfaces with various AT-command sets */
1959 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1960 		USB_CDC_ACM_PROTO_AT_V25TER) },
1961 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1962 		USB_CDC_ACM_PROTO_AT_PCCA101) },
1963 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1964 		USB_CDC_ACM_PROTO_AT_PCCA101_WAKE) },
1965 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1966 		USB_CDC_ACM_PROTO_AT_GSM) },
1967 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1968 		USB_CDC_ACM_PROTO_AT_3G) },
1969 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1970 		USB_CDC_ACM_PROTO_AT_CDMA) },
1971 
1972 	{ USB_DEVICE(0x1519, 0x0452), /* Intel 7260 modem */
1973 	.driver_info = SEND_ZERO_PACKET,
1974 	},
1975 
1976 	{ }
1977 };
1978 
1979 MODULE_DEVICE_TABLE(usb, acm_ids);
1980 
1981 static struct usb_driver acm_driver = {
1982 	.name =		"cdc_acm",
1983 	.probe =	acm_probe,
1984 	.disconnect =	acm_disconnect,
1985 #ifdef CONFIG_PM
1986 	.suspend =	acm_suspend,
1987 	.resume =	acm_resume,
1988 	.reset_resume =	acm_reset_resume,
1989 #endif
1990 	.pre_reset =	acm_pre_reset,
1991 	.id_table =	acm_ids,
1992 #ifdef CONFIG_PM
1993 	.supports_autosuspend = 1,
1994 #endif
1995 	.disable_hub_initiated_lpm = 1,
1996 };
1997 
1998 /*
1999  * TTY driver structures.
2000  */
2001 
2002 static const struct tty_operations acm_ops = {
2003 	.install =		acm_tty_install,
2004 	.open =			acm_tty_open,
2005 	.close =		acm_tty_close,
2006 	.cleanup =		acm_tty_cleanup,
2007 	.hangup =		acm_tty_hangup,
2008 	.write =		acm_tty_write,
2009 	.write_room =		acm_tty_write_room,
2010 	.ioctl =		acm_tty_ioctl,
2011 	.throttle =		acm_tty_throttle,
2012 	.unthrottle =		acm_tty_unthrottle,
2013 	.chars_in_buffer =	acm_tty_chars_in_buffer,
2014 	.break_ctl =		acm_tty_break_ctl,
2015 	.set_termios =		acm_tty_set_termios,
2016 	.tiocmget =		acm_tty_tiocmget,
2017 	.tiocmset =		acm_tty_tiocmset,
2018 	.get_serial =		get_serial_info,
2019 	.set_serial =		set_serial_info,
2020 	.get_icount =		acm_tty_get_icount,
2021 };
2022 
2023 /*
2024  * Init / exit.
2025  */
2026 
2027 static int __init acm_init(void)
2028 {
2029 	int retval;
2030 	acm_tty_driver = tty_alloc_driver(ACM_TTY_MINORS, TTY_DRIVER_REAL_RAW |
2031 			TTY_DRIVER_DYNAMIC_DEV);
2032 	if (IS_ERR(acm_tty_driver))
2033 		return PTR_ERR(acm_tty_driver);
2034 	acm_tty_driver->driver_name = "acm",
2035 	acm_tty_driver->name = "ttyACM",
2036 	acm_tty_driver->major = ACM_TTY_MAJOR,
2037 	acm_tty_driver->minor_start = 0,
2038 	acm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
2039 	acm_tty_driver->subtype = SERIAL_TYPE_NORMAL,
2040 	acm_tty_driver->init_termios = tty_std_termios;
2041 	acm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD |
2042 								HUPCL | CLOCAL;
2043 	tty_set_operations(acm_tty_driver, &acm_ops);
2044 
2045 	retval = tty_register_driver(acm_tty_driver);
2046 	if (retval) {
2047 		tty_driver_kref_put(acm_tty_driver);
2048 		return retval;
2049 	}
2050 
2051 	retval = usb_register(&acm_driver);
2052 	if (retval) {
2053 		tty_unregister_driver(acm_tty_driver);
2054 		tty_driver_kref_put(acm_tty_driver);
2055 		return retval;
2056 	}
2057 
2058 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
2059 
2060 	return 0;
2061 }
2062 
2063 static void __exit acm_exit(void)
2064 {
2065 	usb_deregister(&acm_driver);
2066 	tty_unregister_driver(acm_tty_driver);
2067 	tty_driver_kref_put(acm_tty_driver);
2068 	idr_destroy(&acm_minors);
2069 }
2070 
2071 module_init(acm_init);
2072 module_exit(acm_exit);
2073 
2074 MODULE_AUTHOR(DRIVER_AUTHOR);
2075 MODULE_DESCRIPTION(DRIVER_DESC);
2076 MODULE_LICENSE("GPL");
2077 MODULE_ALIAS_CHARDEV_MAJOR(ACM_TTY_MAJOR);
2078