xref: /linux/drivers/usb/class/cdc-acm.c (revision 5eb070769ea5e18405535609d1d3f6886f3755bd)
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/tty_ldisc.h>
32 #include <linux/module.h>
33 #include <linux/mutex.h>
34 #include <linux/uaccess.h>
35 #include <linux/usb.h>
36 #include <linux/usb/cdc.h>
37 #include <asm/byteorder.h>
38 #include <linux/unaligned.h>
39 #include <linux/idr.h>
40 #include <linux/list.h>
41 
42 #include "cdc-acm.h"
43 
44 
45 #define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek, Johan Hovold"
46 #define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
47 
48 static struct usb_driver acm_driver;
49 static struct tty_driver *acm_tty_driver;
50 
51 static DEFINE_IDR(acm_minors);
52 static DEFINE_MUTEX(acm_minors_lock);
53 
54 static void acm_tty_set_termios(struct tty_struct *tty,
55 				const struct ktermios *termios_old);
56 
57 /*
58  * acm_minors accessors
59  */
60 
61 /*
62  * Look up an ACM structure by minor. If found and not disconnected, increment
63  * its refcount and return it with its mutex held.
64  */
65 static struct acm *acm_get_by_minor(unsigned int minor)
66 {
67 	struct acm *acm;
68 
69 	mutex_lock(&acm_minors_lock);
70 	acm = idr_find(&acm_minors, minor);
71 	if (acm) {
72 		mutex_lock(&acm->mutex);
73 		if (acm->disconnected) {
74 			mutex_unlock(&acm->mutex);
75 			acm = NULL;
76 		} else {
77 			tty_port_get(&acm->port);
78 			mutex_unlock(&acm->mutex);
79 		}
80 	}
81 	mutex_unlock(&acm_minors_lock);
82 	return acm;
83 }
84 
85 /*
86  * Try to find an available minor number and if found, associate it with 'acm'.
87  */
88 static int acm_alloc_minor(struct acm *acm)
89 {
90 	int minor;
91 
92 	mutex_lock(&acm_minors_lock);
93 	minor = idr_alloc(&acm_minors, acm, 0, ACM_TTY_MINORS, GFP_KERNEL);
94 	mutex_unlock(&acm_minors_lock);
95 
96 	return minor;
97 }
98 
99 /* Release the minor number associated with 'acm'.  */
100 static void acm_release_minor(struct acm *acm)
101 {
102 	mutex_lock(&acm_minors_lock);
103 	idr_remove(&acm_minors, acm->minor);
104 	mutex_unlock(&acm_minors_lock);
105 }
106 
107 /*
108  * Functions for ACM control messages.
109  */
110 
111 static int acm_ctrl_msg(struct acm *acm, int request, int value,
112 							void *buf, int len)
113 {
114 	int retval;
115 
116 	retval = usb_autopm_get_interface(acm->control);
117 	if (retval)
118 		return retval;
119 
120 	retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
121 		request, USB_RT_ACM, value,
122 		acm->control->altsetting[0].desc.bInterfaceNumber,
123 		buf, len, USB_CTRL_SET_TIMEOUT);
124 
125 	dev_dbg(&acm->control->dev,
126 		"%s - rq 0x%02x, val %#x, len %#x, result %d\n",
127 		__func__, request, value, len, retval);
128 
129 	usb_autopm_put_interface(acm->control);
130 
131 	return retval < 0 ? retval : 0;
132 }
133 
134 /* devices aren't required to support these requests.
135  * the cdc acm descriptor tells whether they do...
136  */
137 static inline int acm_set_control(struct acm *acm, int control)
138 {
139 	if (acm->quirks & QUIRK_CONTROL_LINE_STATE)
140 		return -EOPNOTSUPP;
141 
142 	return acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE,
143 			control, NULL, 0);
144 }
145 
146 #define acm_set_line(acm, line) \
147 	acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line))
148 #define acm_send_break(acm, ms) \
149 	acm_ctrl_msg(acm, USB_CDC_REQ_SEND_BREAK, ms, NULL, 0)
150 
151 static void acm_poison_urbs(struct acm *acm)
152 {
153 	int i;
154 
155 	usb_poison_urb(acm->ctrlurb);
156 	for (i = 0; i < ACM_NW; i++)
157 		usb_poison_urb(acm->wb[i].urb);
158 	for (i = 0; i < acm->rx_buflimit; i++)
159 		usb_poison_urb(acm->read_urbs[i]);
160 }
161 
162 static void acm_unpoison_urbs(struct acm *acm)
163 {
164 	int i;
165 
166 	for (i = 0; i < acm->rx_buflimit; i++)
167 		usb_unpoison_urb(acm->read_urbs[i]);
168 	for (i = 0; i < ACM_NW; i++)
169 		usb_unpoison_urb(acm->wb[i].urb);
170 	usb_unpoison_urb(acm->ctrlurb);
171 }
172 
173 
174 /*
175  * Write buffer management.
176  * All of these assume proper locks taken by the caller.
177  */
178 
179 static int acm_wb_alloc(struct acm *acm)
180 {
181 	int i, wbn;
182 	struct acm_wb *wb;
183 
184 	wbn = 0;
185 	i = 0;
186 	for (;;) {
187 		wb = &acm->wb[wbn];
188 		if (!wb->use) {
189 			wb->use = true;
190 			wb->len = 0;
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 		if(acm->wb[i].use)
208 			n--;
209 	spin_unlock_irqrestore(&acm->write_lock, flags);
210 	return n;
211 }
212 
213 /*
214  * Finish write. Caller must hold acm->write_lock
215  */
216 static void acm_write_done(struct acm *acm, struct acm_wb *wb)
217 {
218 	wb->use = false;
219 	acm->transmitting--;
220 	usb_autopm_put_interface_async(acm->control);
221 }
222 
223 /*
224  * Poke write.
225  *
226  * the caller is responsible for locking
227  */
228 
229 static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
230 {
231 	int rc;
232 
233 	acm->transmitting++;
234 
235 	wb->urb->transfer_buffer = wb->buf;
236 	wb->urb->transfer_dma = wb->dmah;
237 	wb->urb->transfer_buffer_length = wb->len;
238 	wb->urb->dev = acm->dev;
239 
240 	rc = usb_submit_urb(wb->urb, GFP_ATOMIC);
241 	if (rc < 0) {
242 		if (rc != -EPERM)
243 			dev_err(&acm->data->dev,
244 				"%s - usb_submit_urb(write bulk) failed: %d\n",
245 				__func__, rc);
246 		acm_write_done(acm, wb);
247 	}
248 	return rc;
249 }
250 
251 /*
252  * attributes exported through sysfs
253  */
254 static ssize_t bmCapabilities_show
255 (struct device *dev, struct device_attribute *attr, char *buf)
256 {
257 	struct usb_interface *intf = to_usb_interface(dev);
258 	struct acm *acm = usb_get_intfdata(intf);
259 
260 	return sprintf(buf, "%d", acm->ctrl_caps);
261 }
262 static DEVICE_ATTR_RO(bmCapabilities);
263 
264 static ssize_t wCountryCodes_show
265 (struct device *dev, struct device_attribute *attr, char *buf)
266 {
267 	struct usb_interface *intf = to_usb_interface(dev);
268 	struct acm *acm = usb_get_intfdata(intf);
269 
270 	memcpy(buf, acm->country_codes, acm->country_code_size);
271 	return acm->country_code_size;
272 }
273 
274 static DEVICE_ATTR_RO(wCountryCodes);
275 
276 static ssize_t iCountryCodeRelDate_show
277 (struct device *dev, struct device_attribute *attr, char *buf)
278 {
279 	struct usb_interface *intf = to_usb_interface(dev);
280 	struct acm *acm = usb_get_intfdata(intf);
281 
282 	return sprintf(buf, "%d", acm->country_rel_date);
283 }
284 
285 static DEVICE_ATTR_RO(iCountryCodeRelDate);
286 /*
287  * Interrupt handlers for various ACM device responses
288  */
289 
290 static void acm_process_notification(struct acm *acm, unsigned char *buf)
291 {
292 	int newctrl;
293 	int difference;
294 	unsigned long flags;
295 	struct usb_cdc_notification *dr = (struct usb_cdc_notification *)buf;
296 	unsigned char *data = buf + sizeof(struct usb_cdc_notification);
297 
298 	switch (dr->bNotificationType) {
299 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
300 		dev_dbg(&acm->control->dev,
301 			"%s - network connection: %d\n", __func__, dr->wValue);
302 		break;
303 
304 	case USB_CDC_NOTIFY_SERIAL_STATE:
305 		if (le16_to_cpu(dr->wLength) != 2) {
306 			dev_dbg(&acm->control->dev,
307 				"%s - malformed serial state\n", __func__);
308 			break;
309 		}
310 
311 		newctrl = get_unaligned_le16(data);
312 		dev_dbg(&acm->control->dev,
313 			"%s - serial state: 0x%x\n", __func__, newctrl);
314 
315 		if (!acm->clocal && (acm->ctrlin & ~newctrl & USB_CDC_SERIAL_STATE_DCD)) {
316 			dev_dbg(&acm->control->dev,
317 				"%s - calling hangup\n", __func__);
318 			tty_port_tty_hangup(&acm->port, false);
319 		}
320 
321 		difference = acm->ctrlin ^ newctrl;
322 
323 		if ((difference & USB_CDC_SERIAL_STATE_DCD) && acm->port.tty) {
324 			struct tty_ldisc *ld = tty_ldisc_ref(acm->port.tty);
325 			if (ld) {
326 				if (ld->ops->dcd_change)
327 					ld->ops->dcd_change(acm->port.tty, newctrl & USB_CDC_SERIAL_STATE_DCD);
328 				tty_ldisc_deref(ld);
329 			}
330 		}
331 
332 		spin_lock_irqsave(&acm->read_lock, flags);
333 		acm->ctrlin = newctrl;
334 		acm->oldcount = acm->iocount;
335 
336 		if (difference & USB_CDC_SERIAL_STATE_DSR)
337 			acm->iocount.dsr++;
338 		if (difference & USB_CDC_SERIAL_STATE_DCD)
339 			acm->iocount.dcd++;
340 		if (newctrl & USB_CDC_SERIAL_STATE_BREAK) {
341 			acm->iocount.brk++;
342 			tty_insert_flip_char(&acm->port, 0, TTY_BREAK);
343 		}
344 		if (newctrl & USB_CDC_SERIAL_STATE_RING_SIGNAL)
345 			acm->iocount.rng++;
346 		if (newctrl & USB_CDC_SERIAL_STATE_FRAMING)
347 			acm->iocount.frame++;
348 		if (newctrl & USB_CDC_SERIAL_STATE_PARITY)
349 			acm->iocount.parity++;
350 		if (newctrl & USB_CDC_SERIAL_STATE_OVERRUN)
351 			acm->iocount.overrun++;
352 		spin_unlock_irqrestore(&acm->read_lock, flags);
353 
354 		if (newctrl & USB_CDC_SERIAL_STATE_BREAK)
355 			tty_flip_buffer_push(&acm->port);
356 
357 		if (difference)
358 			wake_up_all(&acm->wioctl);
359 
360 		break;
361 
362 	default:
363 		dev_dbg(&acm->control->dev,
364 			"%s - unknown notification %d received: index %d len %d\n",
365 			__func__,
366 			dr->bNotificationType, dr->wIndex, dr->wLength);
367 	}
368 }
369 
370 /* control interface reports status changes with "interrupt" transfers */
371 static void acm_ctrl_irq(struct urb *urb)
372 {
373 	struct acm *acm = urb->context;
374 	struct usb_cdc_notification *dr;
375 	unsigned int current_size = urb->actual_length;
376 	unsigned int expected_size, copy_size, alloc_size;
377 	int retval;
378 	int status = urb->status;
379 
380 	switch (status) {
381 	case 0:
382 		/* success */
383 		break;
384 	case -ECONNRESET:
385 	case -ENOENT:
386 	case -ESHUTDOWN:
387 		/* this urb is terminated, clean up */
388 		dev_dbg(&acm->control->dev,
389 			"%s - urb shutting down with status: %d\n",
390 			__func__, status);
391 		return;
392 	default:
393 		dev_dbg(&acm->control->dev,
394 			"%s - nonzero urb status received: %d\n",
395 			__func__, status);
396 		goto exit;
397 	}
398 
399 	usb_mark_last_busy(acm->dev);
400 
401 	if (acm->nb_index == 0) {
402 		/*
403 		 * The first chunk of a message must contain at least the
404 		 * notification header with the length field, otherwise we
405 		 * can't get an expected_size.
406 		 */
407 		if (current_size < sizeof(struct usb_cdc_notification)) {
408 			dev_dbg(&acm->control->dev, "urb too short\n");
409 			goto exit;
410 		}
411 		dr = urb->transfer_buffer;
412 	} else {
413 		dr = (struct usb_cdc_notification *)acm->notification_buffer;
414 	}
415 	/* size = notification-header + (optional) data */
416 	expected_size = sizeof(struct usb_cdc_notification) +
417 					le16_to_cpu(dr->wLength);
418 
419 	if (acm->nb_index != 0 || current_size < expected_size) {
420 		/* notification is transmitted fragmented, reassemble */
421 		if (acm->nb_size < expected_size) {
422 			u8 *new_buffer;
423 			alloc_size = roundup_pow_of_two(expected_size);
424 			/* Final freeing is done on disconnect. */
425 			new_buffer = krealloc(acm->notification_buffer,
426 					      alloc_size, GFP_ATOMIC);
427 			if (!new_buffer) {
428 				acm->nb_index = 0;
429 				goto exit;
430 			}
431 
432 			acm->notification_buffer = new_buffer;
433 			acm->nb_size = alloc_size;
434 			dr = (struct usb_cdc_notification *)acm->notification_buffer;
435 		}
436 
437 		copy_size = min(current_size,
438 				expected_size - acm->nb_index);
439 
440 		memcpy(&acm->notification_buffer[acm->nb_index],
441 		       urb->transfer_buffer, copy_size);
442 		acm->nb_index += copy_size;
443 		current_size = acm->nb_index;
444 	}
445 
446 	if (current_size >= expected_size) {
447 		/* notification complete */
448 		acm_process_notification(acm, (unsigned char *)dr);
449 		acm->nb_index = 0;
450 	}
451 
452 exit:
453 	retval = usb_submit_urb(urb, GFP_ATOMIC);
454 	if (retval && retval != -EPERM && retval != -ENODEV)
455 		dev_err(&acm->control->dev,
456 			"%s - usb_submit_urb failed: %d\n", __func__, retval);
457 	else
458 		dev_vdbg(&acm->control->dev,
459 			"control resubmission terminated %d\n", retval);
460 }
461 
462 static int acm_submit_read_urb(struct acm *acm, int index, gfp_t mem_flags)
463 {
464 	int res;
465 
466 	if (!test_and_clear_bit(index, &acm->read_urbs_free))
467 		return 0;
468 
469 	res = usb_submit_urb(acm->read_urbs[index], mem_flags);
470 	if (res) {
471 		if (res != -EPERM && res != -ENODEV) {
472 			dev_err(&acm->data->dev,
473 				"urb %d failed submission with %d\n",
474 				index, res);
475 		} else {
476 			dev_vdbg(&acm->data->dev, "intended failure %d\n", res);
477 		}
478 		set_bit(index, &acm->read_urbs_free);
479 		return res;
480 	} else {
481 		dev_vdbg(&acm->data->dev, "submitted urb %d\n", index);
482 	}
483 
484 	return 0;
485 }
486 
487 static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
488 {
489 	int res;
490 	int i;
491 
492 	for (i = 0; i < acm->rx_buflimit; ++i) {
493 		res = acm_submit_read_urb(acm, i, mem_flags);
494 		if (res)
495 			return res;
496 	}
497 
498 	return 0;
499 }
500 
501 static void acm_process_read_urb(struct acm *acm, struct urb *urb)
502 {
503 	unsigned long flags;
504 
505 	if (!urb->actual_length)
506 		return;
507 
508 	spin_lock_irqsave(&acm->read_lock, flags);
509 	tty_insert_flip_string(&acm->port, urb->transfer_buffer,
510 			urb->actual_length);
511 	spin_unlock_irqrestore(&acm->read_lock, flags);
512 
513 	tty_flip_buffer_push(&acm->port);
514 }
515 
516 static void acm_read_bulk_callback(struct urb *urb)
517 {
518 	struct acm_rb *rb = urb->context;
519 	struct acm *acm = rb->instance;
520 	int status = urb->status;
521 	bool stopped = false;
522 	bool stalled = false;
523 	bool cooldown = false;
524 
525 	dev_vdbg(&acm->data->dev, "got urb %d, len %d, status %d\n",
526 		rb->index, urb->actual_length, status);
527 
528 	switch (status) {
529 	case 0:
530 		usb_mark_last_busy(acm->dev);
531 		acm_process_read_urb(acm, urb);
532 		break;
533 	case -EPIPE:
534 		set_bit(EVENT_RX_STALL, &acm->flags);
535 		stalled = true;
536 		break;
537 	case -ENOENT:
538 	case -ECONNRESET:
539 	case -ESHUTDOWN:
540 		dev_dbg(&acm->data->dev,
541 			"%s - urb shutting down with status: %d\n",
542 			__func__, status);
543 		stopped = true;
544 		break;
545 	case -EOVERFLOW:
546 	case -EPROTO:
547 		dev_dbg(&acm->data->dev,
548 			"%s - cooling babbling device\n", __func__);
549 		usb_mark_last_busy(acm->dev);
550 		set_bit(rb->index, &acm->urbs_in_error_delay);
551 		set_bit(ACM_ERROR_DELAY, &acm->flags);
552 		cooldown = true;
553 		break;
554 	default:
555 		dev_dbg(&acm->data->dev,
556 			"%s - nonzero urb status received: %d\n",
557 			__func__, status);
558 		break;
559 	}
560 
561 	/*
562 	 * Make sure URB processing is done before marking as free to avoid
563 	 * racing with unthrottle() on another CPU. Matches the barriers
564 	 * implied by the test_and_clear_bit() in acm_submit_read_urb().
565 	 */
566 	smp_mb__before_atomic();
567 	set_bit(rb->index, &acm->read_urbs_free);
568 	/*
569 	 * Make sure URB is marked as free before checking the throttled flag
570 	 * to avoid racing with unthrottle() on another CPU. Matches the
571 	 * smp_mb() in unthrottle().
572 	 */
573 	smp_mb__after_atomic();
574 
575 	if (stopped || stalled || cooldown) {
576 		if (stalled)
577 			schedule_delayed_work(&acm->dwork, 0);
578 		else if (cooldown)
579 			schedule_delayed_work(&acm->dwork, HZ / 2);
580 		return;
581 	}
582 
583 	if (test_bit(ACM_THROTTLED, &acm->flags))
584 		return;
585 
586 	acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
587 }
588 
589 /* data interface wrote those outgoing bytes */
590 static void acm_write_bulk(struct urb *urb)
591 {
592 	struct acm_wb *wb = urb->context;
593 	struct acm *acm = wb->instance;
594 	unsigned long flags;
595 	int status = urb->status;
596 
597 	if (status || (urb->actual_length != urb->transfer_buffer_length))
598 		dev_vdbg(&acm->data->dev, "wrote len %d/%d, status %d\n",
599 			urb->actual_length,
600 			urb->transfer_buffer_length,
601 			status);
602 
603 	spin_lock_irqsave(&acm->write_lock, flags);
604 	acm_write_done(acm, wb);
605 	spin_unlock_irqrestore(&acm->write_lock, flags);
606 	set_bit(EVENT_TTY_WAKEUP, &acm->flags);
607 	schedule_delayed_work(&acm->dwork, 0);
608 }
609 
610 static void acm_softint(struct work_struct *work)
611 {
612 	int i;
613 	struct acm *acm = container_of(work, struct acm, dwork.work);
614 
615 	if (test_bit(EVENT_RX_STALL, &acm->flags)) {
616 		smp_mb(); /* against acm_suspend() */
617 		if (!acm->susp_count) {
618 			for (i = 0; i < acm->rx_buflimit; i++)
619 				usb_kill_urb(acm->read_urbs[i]);
620 			usb_clear_halt(acm->dev, acm->in);
621 			acm_submit_read_urbs(acm, GFP_KERNEL);
622 			clear_bit(EVENT_RX_STALL, &acm->flags);
623 		}
624 	}
625 
626 	if (test_and_clear_bit(ACM_ERROR_DELAY, &acm->flags)) {
627 		for (i = 0; i < acm->rx_buflimit; i++)
628 			if (test_and_clear_bit(i, &acm->urbs_in_error_delay))
629 				acm_submit_read_urb(acm, i, GFP_KERNEL);
630 	}
631 
632 	if (test_and_clear_bit(EVENT_TTY_WAKEUP, &acm->flags))
633 		tty_port_tty_wakeup(&acm->port);
634 }
635 
636 /*
637  * TTY handlers
638  */
639 
640 static int acm_tty_install(struct tty_driver *driver, struct tty_struct *tty)
641 {
642 	struct acm *acm;
643 	int retval;
644 
645 	acm = acm_get_by_minor(tty->index);
646 	if (!acm)
647 		return -ENODEV;
648 
649 	retval = tty_standard_install(driver, tty);
650 	if (retval)
651 		goto error_init_termios;
652 
653 	/*
654 	 * Suppress initial echoing for some devices which might send data
655 	 * immediately after acm driver has been installed.
656 	 */
657 	if (acm->quirks & DISABLE_ECHO)
658 		tty->termios.c_lflag &= ~ECHO;
659 
660 	tty->driver_data = acm;
661 
662 	return 0;
663 
664 error_init_termios:
665 	tty_port_put(&acm->port);
666 	return retval;
667 }
668 
669 static int acm_tty_open(struct tty_struct *tty, struct file *filp)
670 {
671 	struct acm *acm = tty->driver_data;
672 
673 	return tty_port_open(&acm->port, tty, filp);
674 }
675 
676 static void acm_port_dtr_rts(struct tty_port *port, bool active)
677 {
678 	struct acm *acm = container_of(port, struct acm, port);
679 	int val;
680 	int res;
681 
682 	if (active)
683 		val = USB_CDC_CTRL_DTR | USB_CDC_CTRL_RTS;
684 	else
685 		val = 0;
686 
687 	/* FIXME: add missing ctrlout locking throughout driver */
688 	acm->ctrlout = val;
689 
690 	res = acm_set_control(acm, val);
691 	if (res && (acm->ctrl_caps & USB_CDC_CAP_LINE))
692 		/* This is broken in too many devices to spam the logs */
693 		dev_dbg(&acm->control->dev, "failed to set dtr/rts\n");
694 }
695 
696 static int acm_port_activate(struct tty_port *port, struct tty_struct *tty)
697 {
698 	struct acm *acm = container_of(port, struct acm, port);
699 	int retval = -ENODEV;
700 	int i;
701 
702 	mutex_lock(&acm->mutex);
703 	if (acm->disconnected)
704 		goto disconnected;
705 
706 	retval = usb_autopm_get_interface(acm->control);
707 	if (retval)
708 		goto error_get_interface;
709 
710 	set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
711 	acm->control->needs_remote_wakeup = 1;
712 
713 	if (!(acm->quirks & ALWAYS_POLL_CTRL)) {
714 		acm->ctrlurb->dev = acm->dev;
715 		retval = usb_submit_urb(acm->ctrlurb, GFP_KERNEL);
716 		if (retval) {
717 			dev_err(&acm->control->dev,
718 				"%s - usb_submit_urb(ctrl irq) failed\n", __func__);
719 			goto error_submit_urb;
720 		}
721 	}
722 
723 	acm_tty_set_termios(tty, NULL);
724 
725 	/*
726 	 * Unthrottle device in case the TTY was closed while throttled.
727 	 */
728 	clear_bit(ACM_THROTTLED, &acm->flags);
729 
730 	retval = acm_submit_read_urbs(acm, GFP_KERNEL);
731 	if (retval)
732 		goto error_submit_read_urbs;
733 
734 	usb_autopm_put_interface(acm->control);
735 
736 	mutex_unlock(&acm->mutex);
737 
738 	return 0;
739 
740 error_submit_read_urbs:
741 	for (i = 0; i < acm->rx_buflimit; i++)
742 		usb_kill_urb(acm->read_urbs[i]);
743 	usb_kill_urb(acm->ctrlurb);
744 error_submit_urb:
745 	usb_autopm_put_interface(acm->control);
746 error_get_interface:
747 disconnected:
748 	mutex_unlock(&acm->mutex);
749 
750 	return usb_translate_errors(retval);
751 }
752 
753 static void acm_port_destruct(struct tty_port *port)
754 {
755 	struct acm *acm = container_of(port, struct acm, port);
756 
757 	if (acm->minor != ACM_MINOR_INVALID)
758 		acm_release_minor(acm);
759 	usb_put_intf(acm->control);
760 	kfree(acm->country_codes);
761 	kfree(acm);
762 }
763 
764 static void acm_port_shutdown(struct tty_port *port)
765 {
766 	struct acm *acm = container_of(port, struct acm, port);
767 	struct urb *urb;
768 	struct acm_wb *wb;
769 
770 	/*
771 	 * Need to grab write_lock to prevent race with resume, but no need to
772 	 * hold it due to the tty-port initialised flag.
773 	 */
774 	acm_poison_urbs(acm);
775 	spin_lock_irq(&acm->write_lock);
776 	spin_unlock_irq(&acm->write_lock);
777 
778 	usb_autopm_get_interface_no_resume(acm->control);
779 	acm->control->needs_remote_wakeup = 0;
780 	usb_autopm_put_interface(acm->control);
781 
782 	for (;;) {
783 		urb = usb_get_from_anchor(&acm->delayed);
784 		if (!urb)
785 			break;
786 		wb = urb->context;
787 		wb->use = false;
788 		usb_autopm_put_interface_async(acm->control);
789 	}
790 
791 	acm_unpoison_urbs(acm);
792 
793 	if (acm->quirks & ALWAYS_POLL_CTRL) {
794 		acm->ctrlurb->dev = acm->dev;
795 		if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL))
796 			dev_dbg(&acm->control->dev,
797 				"ctrl polling restart failed after port close\n");
798 		/* port_shutdown() cleared DTR/RTS; restore them */
799 		acm_set_control(acm, USB_CDC_CTRL_DTR | USB_CDC_CTRL_RTS);
800 	}
801 }
802 
803 static void acm_tty_cleanup(struct tty_struct *tty)
804 {
805 	struct acm *acm = tty->driver_data;
806 
807 	tty_port_put(&acm->port);
808 }
809 
810 static void acm_tty_hangup(struct tty_struct *tty)
811 {
812 	struct acm *acm = tty->driver_data;
813 
814 	tty_port_hangup(&acm->port);
815 }
816 
817 static void acm_tty_close(struct tty_struct *tty, struct file *filp)
818 {
819 	struct acm *acm = tty->driver_data;
820 
821 	tty_port_close(&acm->port, tty, filp);
822 }
823 
824 static ssize_t acm_tty_write(struct tty_struct *tty, const u8 *buf,
825 			     size_t count)
826 {
827 	struct acm *acm = tty->driver_data;
828 	int stat;
829 	unsigned long flags;
830 	int wbn;
831 	struct acm_wb *wb;
832 
833 	if (!count)
834 		return 0;
835 
836 	dev_vdbg(&acm->data->dev, "%zu bytes from tty layer\n", count);
837 
838 	spin_lock_irqsave(&acm->write_lock, flags);
839 	wbn = acm_wb_alloc(acm);
840 	if (wbn < 0) {
841 		spin_unlock_irqrestore(&acm->write_lock, flags);
842 		return 0;
843 	}
844 	wb = &acm->wb[wbn];
845 
846 	if (!acm->dev) {
847 		wb->use = false;
848 		spin_unlock_irqrestore(&acm->write_lock, flags);
849 		return -ENODEV;
850 	}
851 
852 	count = (count > acm->writesize) ? acm->writesize : count;
853 	dev_vdbg(&acm->data->dev, "writing %zu bytes\n", count);
854 	memcpy(wb->buf, buf, count);
855 	wb->len = count;
856 
857 	stat = usb_autopm_get_interface_async(acm->control);
858 	if (stat) {
859 		wb->use = false;
860 		spin_unlock_irqrestore(&acm->write_lock, flags);
861 		return stat;
862 	}
863 
864 	if (acm->susp_count) {
865 		usb_anchor_urb(wb->urb, &acm->delayed);
866 		spin_unlock_irqrestore(&acm->write_lock, flags);
867 		return count;
868 	}
869 
870 	stat = acm_start_wb(acm, wb);
871 	spin_unlock_irqrestore(&acm->write_lock, flags);
872 
873 	if (stat < 0)
874 		return stat;
875 	return count;
876 }
877 
878 static unsigned int acm_tty_write_room(struct tty_struct *tty)
879 {
880 	struct acm *acm = tty->driver_data;
881 	/*
882 	 * Do not let the line discipline to know that we have a reserve,
883 	 * or it might get too enthusiastic.
884 	 */
885 	return acm_wb_is_avail(acm) ? acm->writesize : 0;
886 }
887 
888 static void acm_tty_flush_buffer(struct tty_struct *tty)
889 {
890 	struct acm *acm = tty->driver_data;
891 	unsigned long flags;
892 	int i;
893 
894 	spin_lock_irqsave(&acm->write_lock, flags);
895 	for (i = 0; i < ACM_NW; i++)
896 		if (acm->wb[i].use)
897 			usb_unlink_urb(acm->wb[i].urb);
898 	spin_unlock_irqrestore(&acm->write_lock, flags);
899 }
900 
901 static unsigned int acm_tty_chars_in_buffer(struct tty_struct *tty)
902 {
903 	struct acm *acm = tty->driver_data;
904 	/*
905 	 * if the device was unplugged then any remaining characters fell out
906 	 * of the connector ;)
907 	 */
908 	if (acm->disconnected)
909 		return 0;
910 	/*
911 	 * This is inaccurate (overcounts), but it works.
912 	 */
913 	return (ACM_NW - acm_wb_is_avail(acm)) * acm->writesize;
914 }
915 
916 static void acm_tty_throttle(struct tty_struct *tty)
917 {
918 	struct acm *acm = tty->driver_data;
919 
920 	set_bit(ACM_THROTTLED, &acm->flags);
921 }
922 
923 static void acm_tty_unthrottle(struct tty_struct *tty)
924 {
925 	struct acm *acm = tty->driver_data;
926 
927 	clear_bit(ACM_THROTTLED, &acm->flags);
928 
929 	/* Matches the smp_mb__after_atomic() in acm_read_bulk_callback(). */
930 	smp_mb();
931 
932 	acm_submit_read_urbs(acm, GFP_KERNEL);
933 }
934 
935 static int acm_tty_break_ctl(struct tty_struct *tty, int state)
936 {
937 	struct acm *acm = tty->driver_data;
938 	int retval;
939 
940 	if (!(acm->ctrl_caps & USB_CDC_CAP_BRK))
941 		return -EOPNOTSUPP;
942 
943 	retval = acm_send_break(acm, state ? 0xffff : 0);
944 	if (retval < 0)
945 		dev_dbg(&acm->control->dev,
946 			"%s - send break failed\n", __func__);
947 	return retval;
948 }
949 
950 static int acm_tty_tiocmget(struct tty_struct *tty)
951 {
952 	struct acm *acm = tty->driver_data;
953 
954 	return (acm->ctrlout & USB_CDC_CTRL_DTR ? TIOCM_DTR : 0) |
955 	       (acm->ctrlout & USB_CDC_CTRL_RTS ? TIOCM_RTS : 0) |
956 	       (acm->ctrlin  & USB_CDC_SERIAL_STATE_DSR ? TIOCM_DSR : 0) |
957 	       (acm->ctrlin  & USB_CDC_SERIAL_STATE_RING_SIGNAL ? TIOCM_RI : 0) |
958 	       (acm->ctrlin  & USB_CDC_SERIAL_STATE_DCD ? TIOCM_CD : 0) |
959 	       TIOCM_CTS;
960 }
961 
962 static int acm_tty_tiocmset(struct tty_struct *tty,
963 			    unsigned int set, unsigned int clear)
964 {
965 	struct acm *acm = tty->driver_data;
966 	unsigned int newctrl;
967 
968 	newctrl = acm->ctrlout;
969 	set = (set & TIOCM_DTR ? USB_CDC_CTRL_DTR : 0) |
970 	      (set & TIOCM_RTS ? USB_CDC_CTRL_RTS : 0);
971 	clear = (clear & TIOCM_DTR ? USB_CDC_CTRL_DTR : 0) |
972 		(clear & TIOCM_RTS ? USB_CDC_CTRL_RTS : 0);
973 
974 	newctrl = (newctrl & ~clear) | set;
975 
976 	if (acm->ctrlout == newctrl)
977 		return 0;
978 	return acm_set_control(acm, acm->ctrlout = newctrl);
979 }
980 
981 static int get_serial_info(struct tty_struct *tty, struct serial_struct *ss)
982 {
983 	struct acm *acm = tty->driver_data;
984 
985 	ss->line = acm->minor;
986 	mutex_lock(&acm->port.mutex);
987 	ss->close_delay	= jiffies_to_msecs(acm->port.close_delay) / 10;
988 	ss->closing_wait = acm->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
989 				ASYNC_CLOSING_WAIT_NONE :
990 				jiffies_to_msecs(acm->port.closing_wait) / 10;
991 	mutex_unlock(&acm->port.mutex);
992 	return 0;
993 }
994 
995 static int set_serial_info(struct tty_struct *tty, struct serial_struct *ss)
996 {
997 	struct acm *acm = tty->driver_data;
998 	unsigned int closing_wait, close_delay;
999 	int retval = 0;
1000 
1001 	close_delay = msecs_to_jiffies(ss->close_delay * 10);
1002 	closing_wait = ss->closing_wait == ASYNC_CLOSING_WAIT_NONE ?
1003 			ASYNC_CLOSING_WAIT_NONE :
1004 			msecs_to_jiffies(ss->closing_wait * 10);
1005 
1006 	mutex_lock(&acm->port.mutex);
1007 
1008 	if (!capable(CAP_SYS_ADMIN)) {
1009 		if ((close_delay != acm->port.close_delay) ||
1010 		    (closing_wait != acm->port.closing_wait))
1011 			retval = -EPERM;
1012 	} else {
1013 		acm->port.close_delay  = close_delay;
1014 		acm->port.closing_wait = closing_wait;
1015 	}
1016 
1017 	mutex_unlock(&acm->port.mutex);
1018 	return retval;
1019 }
1020 
1021 static int wait_serial_change(struct acm *acm, unsigned long arg)
1022 {
1023 	int rv = 0;
1024 	DECLARE_WAITQUEUE(wait, current);
1025 	struct async_icount old, new;
1026 
1027 	do {
1028 		spin_lock_irq(&acm->read_lock);
1029 		old = acm->oldcount;
1030 		new = acm->iocount;
1031 		acm->oldcount = new;
1032 		spin_unlock_irq(&acm->read_lock);
1033 
1034 		if ((arg & TIOCM_DSR) &&
1035 			old.dsr != new.dsr)
1036 			break;
1037 		if ((arg & TIOCM_CD)  &&
1038 			old.dcd != new.dcd)
1039 			break;
1040 		if ((arg & TIOCM_RI) &&
1041 			old.rng != new.rng)
1042 			break;
1043 
1044 		add_wait_queue(&acm->wioctl, &wait);
1045 		set_current_state(TASK_INTERRUPTIBLE);
1046 		schedule();
1047 		remove_wait_queue(&acm->wioctl, &wait);
1048 		if (acm->disconnected) {
1049 			if (arg & TIOCM_CD)
1050 				break;
1051 			else
1052 				rv = -ENODEV;
1053 		} else {
1054 			if (signal_pending(current))
1055 				rv = -ERESTARTSYS;
1056 		}
1057 	} while (!rv);
1058 
1059 
1060 
1061 	return rv;
1062 }
1063 
1064 static int acm_tty_get_icount(struct tty_struct *tty,
1065 					struct serial_icounter_struct *icount)
1066 {
1067 	struct acm *acm = tty->driver_data;
1068 
1069 	icount->dsr = acm->iocount.dsr;
1070 	icount->rng = acm->iocount.rng;
1071 	icount->dcd = acm->iocount.dcd;
1072 	icount->frame = acm->iocount.frame;
1073 	icount->overrun = acm->iocount.overrun;
1074 	icount->parity = acm->iocount.parity;
1075 	icount->brk = acm->iocount.brk;
1076 
1077 	return 0;
1078 }
1079 
1080 static int acm_tty_ioctl(struct tty_struct *tty,
1081 					unsigned int cmd, unsigned long arg)
1082 {
1083 	struct acm *acm = tty->driver_data;
1084 	int rv = -ENOIOCTLCMD;
1085 
1086 	switch (cmd) {
1087 	case TIOCMIWAIT:
1088 		rv = usb_autopm_get_interface(acm->control);
1089 		if (rv < 0) {
1090 			rv = -EIO;
1091 			break;
1092 		}
1093 		rv = wait_serial_change(acm, arg);
1094 		usb_autopm_put_interface(acm->control);
1095 		break;
1096 	}
1097 
1098 	return rv;
1099 }
1100 
1101 static void acm_tty_set_termios(struct tty_struct *tty,
1102 				const struct ktermios *termios_old)
1103 {
1104 	struct acm *acm = tty->driver_data;
1105 	struct ktermios *termios = &tty->termios;
1106 	struct usb_cdc_line_coding newline;
1107 	int newctrl = acm->ctrlout;
1108 
1109 	newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
1110 	newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
1111 	newline.bParityType = termios->c_cflag & PARENB ?
1112 				(termios->c_cflag & PARODD ? 1 : 2) +
1113 				(termios->c_cflag & CMSPAR ? 2 : 0) : 0;
1114 	newline.bDataBits = tty_get_char_size(termios->c_cflag);
1115 
1116 	/* FIXME: Needs to clear unsupported bits in the termios */
1117 	acm->clocal = ((termios->c_cflag & CLOCAL) != 0);
1118 
1119 	if (C_BAUD(tty) == B0) {
1120 		newline.dwDTERate = acm->line.dwDTERate;
1121 		newctrl &= ~USB_CDC_CTRL_DTR;
1122 	} else if (termios_old && (termios_old->c_cflag & CBAUD) == B0) {
1123 		newctrl |=  USB_CDC_CTRL_DTR;
1124 	}
1125 
1126 	if (newctrl != acm->ctrlout)
1127 		acm_set_control(acm, acm->ctrlout = newctrl);
1128 
1129 	if (memcmp(&acm->line, &newline, sizeof newline)) {
1130 		memcpy(&acm->line, &newline, sizeof newline);
1131 		dev_dbg(&acm->control->dev, "%s - set line: %d %d %d %d\n",
1132 			__func__,
1133 			le32_to_cpu(newline.dwDTERate),
1134 			newline.bCharFormat, newline.bParityType,
1135 			newline.bDataBits);
1136 		acm_set_line(acm, &acm->line);
1137 	}
1138 }
1139 
1140 static const struct tty_port_operations acm_port_ops = {
1141 	.dtr_rts = acm_port_dtr_rts,
1142 	.shutdown = acm_port_shutdown,
1143 	.activate = acm_port_activate,
1144 	.destruct = acm_port_destruct,
1145 };
1146 
1147 /*
1148  * USB probe and disconnect routines.
1149  */
1150 
1151 /* Little helpers: write/read buffers free */
1152 static void acm_write_buffers_free(struct acm *acm)
1153 {
1154 	int i;
1155 	struct acm_wb *wb;
1156 
1157 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++)
1158 		usb_free_coherent(acm->dev, acm->writesize, wb->buf, wb->dmah);
1159 }
1160 
1161 static void acm_read_buffers_free(struct acm *acm)
1162 {
1163 	int i;
1164 
1165 	for (i = 0; i < acm->rx_buflimit; i++)
1166 		usb_free_coherent(acm->dev, acm->readsize,
1167 			  acm->read_buffers[i].base, acm->read_buffers[i].dma);
1168 }
1169 
1170 /* Little helper: write buffers allocate */
1171 static int acm_write_buffers_alloc(struct acm *acm)
1172 {
1173 	int i;
1174 	struct acm_wb *wb;
1175 
1176 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++) {
1177 		wb->buf = usb_alloc_coherent(acm->dev, acm->writesize, GFP_KERNEL,
1178 		    &wb->dmah);
1179 		if (!wb->buf) {
1180 			while (i != 0) {
1181 				--i;
1182 				--wb;
1183 				usb_free_coherent(acm->dev, acm->writesize,
1184 				    wb->buf, wb->dmah);
1185 			}
1186 			return -ENOMEM;
1187 		}
1188 	}
1189 	return 0;
1190 }
1191 
1192 static int acm_probe(struct usb_interface *intf,
1193 		     const struct usb_device_id *id)
1194 {
1195 	struct usb_cdc_union_desc *union_header = NULL;
1196 	struct usb_cdc_call_mgmt_descriptor *cmgmd = NULL;
1197 	unsigned char *buffer = intf->altsetting->extra;
1198 	int buflen = intf->altsetting->extralen;
1199 	struct usb_interface *control_interface;
1200 	struct usb_interface *data_interface;
1201 	struct usb_endpoint_descriptor *epctrl = NULL;
1202 	struct usb_endpoint_descriptor *epread = NULL;
1203 	struct usb_endpoint_descriptor *epwrite = NULL;
1204 	struct usb_device *usb_dev = interface_to_usbdev(intf);
1205 	struct usb_cdc_parsed_header h;
1206 	struct acm *acm;
1207 	int minor;
1208 	int ctrlsize, readsize;
1209 	u8 *buf;
1210 	int call_intf_num = -1;
1211 	int data_intf_num = -1;
1212 	unsigned long quirks;
1213 	int num_rx_buf;
1214 	int i;
1215 	int combined_interfaces = 0;
1216 	struct device *tty_dev;
1217 	int rv = -ENOMEM;
1218 	int res;
1219 
1220 	/* normal quirks */
1221 	quirks = (unsigned long)id->driver_info;
1222 
1223 	if (quirks == IGNORE_DEVICE)
1224 		return -ENODEV;
1225 
1226 	memset(&h, 0x00, sizeof(struct usb_cdc_parsed_header));
1227 
1228 	num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;
1229 
1230 	/* handle quirks deadly to normal probing*/
1231 	if (quirks == NO_UNION_NORMAL) {
1232 		data_interface = usb_ifnum_to_if(usb_dev, 1);
1233 		control_interface = usb_ifnum_to_if(usb_dev, 0);
1234 		/* we would crash */
1235 		if (!data_interface || !control_interface)
1236 			return -ENODEV;
1237 		goto skip_normal_probe;
1238 	} else if (quirks == NO_UNION_12) {
1239 		data_interface = usb_ifnum_to_if(usb_dev, 2);
1240 		control_interface = usb_ifnum_to_if(usb_dev, 1);
1241 		if (!data_interface || !control_interface)
1242 			 return -ENODEV;
1243 		goto skip_normal_probe;
1244 	}
1245 
1246 	/* normal probing*/
1247 	if (!buffer) {
1248 		dev_err(&intf->dev, "Weird descriptor references\n");
1249 		return -EINVAL;
1250 	}
1251 
1252 	if (!buflen) {
1253 		if (intf->cur_altsetting->endpoint &&
1254 				intf->cur_altsetting->endpoint->extralen &&
1255 				intf->cur_altsetting->endpoint->extra) {
1256 			dev_dbg(&intf->dev,
1257 				"Seeking extra descriptors on endpoint\n");
1258 			buflen = intf->cur_altsetting->endpoint->extralen;
1259 			buffer = intf->cur_altsetting->endpoint->extra;
1260 		} else {
1261 			dev_err(&intf->dev,
1262 				"Zero length descriptor references\n");
1263 			return -EINVAL;
1264 		}
1265 	}
1266 
1267 	cdc_parse_cdc_header(&h, intf, buffer, buflen);
1268 	union_header = h.usb_cdc_union_desc;
1269 	cmgmd = h.usb_cdc_call_mgmt_descriptor;
1270 	if (cmgmd)
1271 		call_intf_num = cmgmd->bDataInterface;
1272 
1273 	if (!union_header) {
1274 		if (intf->cur_altsetting->desc.bNumEndpoints == 3) {
1275 			dev_dbg(&intf->dev, "No union descriptor, assuming single interface\n");
1276 			combined_interfaces = 1;
1277 			control_interface = data_interface = intf;
1278 			goto look_for_collapsed_interface;
1279 		} else if (call_intf_num > 0) {
1280 			dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n");
1281 			data_intf_num = call_intf_num;
1282 			data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
1283 			control_interface = intf;
1284 		} else {
1285 			dev_dbg(&intf->dev, "No union descriptor, giving up\n");
1286 			return -ENODEV;
1287 		}
1288 	} else {
1289 		int class = -1;
1290 
1291 		data_intf_num = union_header->bSlaveInterface0;
1292 		control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
1293 		data_interface = usb_ifnum_to_if(usb_dev, data_intf_num);
1294 
1295 		if (control_interface)
1296 			class = control_interface->cur_altsetting->desc.bInterfaceClass;
1297 
1298 		if (class != USB_CLASS_COMM && class != USB_CLASS_CDC_DATA) {
1299 			dev_dbg(&intf->dev, "Broken union descriptor, assuming single interface\n");
1300 			combined_interfaces = 1;
1301 			control_interface = data_interface = intf;
1302 			goto look_for_collapsed_interface;
1303 		}
1304 	}
1305 
1306 	if (!control_interface || !data_interface) {
1307 		dev_dbg(&intf->dev, "no interfaces\n");
1308 		return -ENODEV;
1309 	}
1310 
1311 	if (data_intf_num != call_intf_num)
1312 		dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");
1313 
1314 	if (control_interface == data_interface) {
1315 		/* some broken devices designed for windows work this way */
1316 		dev_warn(&intf->dev,"Control and data interfaces are not separated!\n");
1317 		combined_interfaces = 1;
1318 		/* a popular other OS doesn't use it */
1319 		quirks |= NO_CAP_LINE;
1320 		if (data_interface->cur_altsetting->desc.bNumEndpoints != 3) {
1321 			dev_err(&intf->dev, "This needs exactly 3 endpoints\n");
1322 			return -EINVAL;
1323 		}
1324 look_for_collapsed_interface:
1325 		res = usb_find_common_endpoints(data_interface->cur_altsetting,
1326 				&epread, &epwrite, &epctrl, NULL);
1327 		if (res)
1328 			return res;
1329 
1330 		goto made_compressed_probe;
1331 	}
1332 
1333 skip_normal_probe:
1334 
1335 	/*workaround for switched interfaces */
1336 	if (data_interface->cur_altsetting->desc.bInterfaceClass != USB_CLASS_CDC_DATA) {
1337 		if (control_interface->cur_altsetting->desc.bInterfaceClass == USB_CLASS_CDC_DATA) {
1338 			dev_dbg(&intf->dev,
1339 				"Your device has switched interfaces.\n");
1340 			swap(control_interface, data_interface);
1341 		} else if (quirks & VENDOR_CLASS_DATA_IFACE) {
1342 			dev_dbg(&intf->dev,
1343 				"Vendor-specific data interface class, continuing.\n");
1344 		} else {
1345 			return -EINVAL;
1346 		}
1347 	}
1348 
1349 	/* Accept probe requests only for the control interface */
1350 	if (!combined_interfaces && intf != control_interface)
1351 		return -ENODEV;
1352 
1353 	if (data_interface->cur_altsetting->desc.bNumEndpoints < 2 ||
1354 	    control_interface->cur_altsetting->desc.bNumEndpoints == 0)
1355 		return -EINVAL;
1356 
1357 	epctrl = &control_interface->cur_altsetting->endpoint[0].desc;
1358 	epread = &data_interface->cur_altsetting->endpoint[0].desc;
1359 	epwrite = &data_interface->cur_altsetting->endpoint[1].desc;
1360 
1361 
1362 	/* workaround for switched endpoints */
1363 	if (!usb_endpoint_dir_in(epread)) {
1364 		/* descriptors are swapped */
1365 		dev_dbg(&intf->dev,
1366 			"The data interface has switched endpoints\n");
1367 		swap(epread, epwrite);
1368 	}
1369 made_compressed_probe:
1370 	dev_dbg(&intf->dev, "interfaces are valid\n");
1371 
1372 	acm = kzalloc_obj(struct acm);
1373 	if (!acm)
1374 		return -ENOMEM;
1375 
1376 	tty_port_init(&acm->port);
1377 	acm->port.ops = &acm_port_ops;
1378 
1379 	ctrlsize = usb_endpoint_maxp(epctrl);
1380 	readsize = usb_endpoint_maxp(epread) *
1381 				(quirks == SINGLE_RX_URB ? 1 : 2);
1382 	acm->combined_interfaces = combined_interfaces;
1383 	acm->writesize = usb_endpoint_maxp(epwrite) * 20;
1384 	acm->control = control_interface;
1385 	acm->data = data_interface;
1386 
1387 	usb_get_intf(acm->control); /* undone in destruct() */
1388 
1389 	minor = acm_alloc_minor(acm);
1390 	if (minor < 0) {
1391 		acm->minor = ACM_MINOR_INVALID;
1392 		goto err_put_port;
1393 	}
1394 
1395 	acm->minor = minor;
1396 	acm->dev = usb_dev;
1397 	if (h.usb_cdc_acm_descriptor)
1398 		acm->ctrl_caps = h.usb_cdc_acm_descriptor->bmCapabilities;
1399 	if (quirks & NO_CAP_LINE)
1400 		acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
1401 	if (quirks & MISSING_CAP_BRK)
1402 		acm->ctrl_caps |= USB_CDC_CAP_BRK;
1403 	acm->ctrlsize = ctrlsize;
1404 	acm->readsize = readsize;
1405 	acm->rx_buflimit = num_rx_buf;
1406 	INIT_DELAYED_WORK(&acm->dwork, acm_softint);
1407 	init_waitqueue_head(&acm->wioctl);
1408 	spin_lock_init(&acm->write_lock);
1409 	spin_lock_init(&acm->read_lock);
1410 	mutex_init(&acm->mutex);
1411 	if (usb_endpoint_xfer_int(epread)) {
1412 		acm->bInterval = epread->bInterval;
1413 		acm->in = usb_rcvintpipe(usb_dev, epread->bEndpointAddress);
1414 	} else {
1415 		acm->in = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
1416 	}
1417 	if (usb_endpoint_xfer_int(epwrite))
1418 		acm->out = usb_sndintpipe(usb_dev, epwrite->bEndpointAddress);
1419 	else
1420 		acm->out = usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress);
1421 	init_usb_anchor(&acm->delayed);
1422 	acm->quirks = quirks;
1423 
1424 	buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
1425 	if (!buf)
1426 		goto err_put_port;
1427 	acm->ctrl_buffer = buf;
1428 
1429 	if (acm_write_buffers_alloc(acm) < 0)
1430 		goto err_free_ctrl_buffer;
1431 
1432 	acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
1433 	if (!acm->ctrlurb)
1434 		goto err_free_write_buffers;
1435 
1436 	for (i = 0; i < num_rx_buf; i++) {
1437 		struct acm_rb *rb = &(acm->read_buffers[i]);
1438 		struct urb *urb;
1439 
1440 		rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
1441 								&rb->dma);
1442 		if (!rb->base)
1443 			goto err_free_read_urbs;
1444 		rb->index = i;
1445 		rb->instance = acm;
1446 
1447 		urb = usb_alloc_urb(0, GFP_KERNEL);
1448 		if (!urb)
1449 			goto err_free_read_urbs;
1450 
1451 		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1452 		urb->transfer_dma = rb->dma;
1453 		if (usb_endpoint_xfer_int(epread))
1454 			usb_fill_int_urb(urb, acm->dev, acm->in, rb->base,
1455 					 acm->readsize,
1456 					 acm_read_bulk_callback, rb,
1457 					 acm->bInterval);
1458 		else
1459 			usb_fill_bulk_urb(urb, acm->dev, acm->in, rb->base,
1460 					  acm->readsize,
1461 					  acm_read_bulk_callback, rb);
1462 
1463 		acm->read_urbs[i] = urb;
1464 		__set_bit(i, &acm->read_urbs_free);
1465 	}
1466 	for (i = 0; i < ACM_NW; i++) {
1467 		struct acm_wb *snd = &(acm->wb[i]);
1468 
1469 		snd->urb = usb_alloc_urb(0, GFP_KERNEL);
1470 		if (!snd->urb)
1471 			goto err_free_write_urbs;
1472 
1473 		if (usb_endpoint_xfer_int(epwrite))
1474 			usb_fill_int_urb(snd->urb, usb_dev, acm->out,
1475 				NULL, acm->writesize, acm_write_bulk, snd, epwrite->bInterval);
1476 		else
1477 			usb_fill_bulk_urb(snd->urb, usb_dev, acm->out,
1478 				NULL, acm->writesize, acm_write_bulk, snd);
1479 		snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1480 		if (quirks & SEND_ZERO_PACKET)
1481 			snd->urb->transfer_flags |= URB_ZERO_PACKET;
1482 		snd->instance = acm;
1483 	}
1484 
1485 	usb_set_intfdata(intf, acm);
1486 
1487 	i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
1488 	if (i < 0)
1489 		goto err_free_write_urbs;
1490 
1491 	if (h.usb_cdc_country_functional_desc) { /* export the country data */
1492 		struct usb_cdc_country_functional_desc * cfd =
1493 					h.usb_cdc_country_functional_desc;
1494 
1495 		acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
1496 		if (!acm->country_codes)
1497 			goto skip_countries;
1498 		acm->country_code_size = cfd->bLength - 4;
1499 		memcpy(acm->country_codes, cfd->wCountryCodes,
1500 							cfd->bLength - 4);
1501 		acm->country_rel_date = cfd->iCountryCodeRelDate;
1502 
1503 		i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
1504 		if (i < 0) {
1505 			kfree(acm->country_codes);
1506 			acm->country_codes = NULL;
1507 			acm->country_code_size = 0;
1508 			goto skip_countries;
1509 		}
1510 
1511 		i = device_create_file(&intf->dev,
1512 						&dev_attr_iCountryCodeRelDate);
1513 		if (i < 0) {
1514 			device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
1515 			kfree(acm->country_codes);
1516 			acm->country_codes = NULL;
1517 			acm->country_code_size = 0;
1518 			goto skip_countries;
1519 		}
1520 	}
1521 
1522 skip_countries:
1523 	usb_fill_int_urb(acm->ctrlurb, usb_dev,
1524 			 usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
1525 			 acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
1526 			 /* works around buggy devices */
1527 			 epctrl->bInterval ? epctrl->bInterval : 16);
1528 	acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1529 	acm->ctrlurb->transfer_dma = acm->ctrl_dma;
1530 	acm->notification_buffer = NULL;
1531 	acm->nb_index = 0;
1532 	acm->nb_size = 0;
1533 
1534 	acm->line.dwDTERate = cpu_to_le32(9600);
1535 	acm->line.bDataBits = 8;
1536 	acm_set_line(acm, &acm->line);
1537 
1538 	if (quirks & ALWAYS_POLL_CTRL)
1539 		acm_set_control(acm, USB_CDC_CTRL_DTR | USB_CDC_CTRL_RTS);
1540 
1541 	if (!acm->combined_interfaces) {
1542 		rv = usb_driver_claim_interface(&acm_driver, data_interface, acm);
1543 		if (rv)
1544 			goto err_remove_files;
1545 	}
1546 
1547 	if (quirks & CLEAR_HALT_CONDITIONS) {
1548 		/* errors intentionally ignored */
1549 		usb_clear_halt(usb_dev, acm->in);
1550 		usb_clear_halt(usb_dev, acm->out);
1551 	}
1552 
1553 	tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
1554 			&control_interface->dev);
1555 	if (IS_ERR(tty_dev)) {
1556 		rv = PTR_ERR(tty_dev);
1557 		goto err_release_data_interface;
1558 	}
1559 
1560 	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
1561 
1562 	if (acm->quirks & ALWAYS_POLL_CTRL) {
1563 		acm->ctrlurb->dev = acm->dev;
1564 		if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL))
1565 			dev_warn(&intf->dev,
1566 				 "failed to start persistent ctrl polling\n");
1567 	}
1568 
1569 	return 0;
1570 
1571 err_release_data_interface:
1572 	if (!acm->combined_interfaces) {
1573 		/* Clear driver data so that disconnect() returns early. */
1574 		usb_set_intfdata(data_interface, NULL);
1575 		usb_driver_release_interface(&acm_driver, data_interface);
1576 	}
1577 err_remove_files:
1578 	if (acm->country_codes) {
1579 		device_remove_file(&acm->control->dev,
1580 				&dev_attr_wCountryCodes);
1581 		device_remove_file(&acm->control->dev,
1582 				&dev_attr_iCountryCodeRelDate);
1583 	}
1584 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1585 err_free_write_urbs:
1586 	for (i = 0; i < ACM_NW; i++)
1587 		usb_free_urb(acm->wb[i].urb);
1588 err_free_read_urbs:
1589 	for (i = 0; i < num_rx_buf; i++)
1590 		usb_free_urb(acm->read_urbs[i]);
1591 	acm_read_buffers_free(acm);
1592 	usb_free_urb(acm->ctrlurb);
1593 err_free_write_buffers:
1594 	acm_write_buffers_free(acm);
1595 err_free_ctrl_buffer:
1596 	usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1597 err_put_port:
1598 	tty_port_put(&acm->port);
1599 
1600 	return rv;
1601 }
1602 
1603 static void acm_disconnect(struct usb_interface *intf)
1604 {
1605 	struct acm *acm = usb_get_intfdata(intf);
1606 	int i;
1607 
1608 	/* sibling interface is already cleaning up */
1609 	if (!acm)
1610 		return;
1611 
1612 	acm->disconnected = true;
1613 	/*
1614 	 * there is a circular dependency. acm_softint() can resubmit
1615 	 * the URBs in error handling so we need to block any
1616 	 * submission right away
1617 	 */
1618 	acm_poison_urbs(acm);
1619 	mutex_lock(&acm->mutex);
1620 	if (acm->country_codes) {
1621 		device_remove_file(&acm->control->dev,
1622 				&dev_attr_wCountryCodes);
1623 		device_remove_file(&acm->control->dev,
1624 				&dev_attr_iCountryCodeRelDate);
1625 	}
1626 	wake_up_all(&acm->wioctl);
1627 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1628 	usb_set_intfdata(acm->control, NULL);
1629 	usb_set_intfdata(acm->data, NULL);
1630 	mutex_unlock(&acm->mutex);
1631 
1632 	tty_port_tty_vhangup(&acm->port);
1633 
1634 	cancel_delayed_work_sync(&acm->dwork);
1635 
1636 	tty_unregister_device(acm_tty_driver, acm->minor);
1637 
1638 	usb_free_urb(acm->ctrlurb);
1639 	for (i = 0; i < ACM_NW; i++)
1640 		usb_free_urb(acm->wb[i].urb);
1641 	for (i = 0; i < acm->rx_buflimit; i++)
1642 		usb_free_urb(acm->read_urbs[i]);
1643 	acm_write_buffers_free(acm);
1644 	usb_free_coherent(acm->dev, acm->ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1645 	acm_read_buffers_free(acm);
1646 
1647 	kfree(acm->notification_buffer);
1648 
1649 	if (!acm->combined_interfaces)
1650 		usb_driver_release_interface(&acm_driver, intf == acm->control ?
1651 					acm->data : acm->control);
1652 
1653 	tty_port_put(&acm->port);
1654 }
1655 
1656 #ifdef CONFIG_PM
1657 static int acm_suspend(struct usb_interface *intf, pm_message_t message)
1658 {
1659 	struct acm *acm = usb_get_intfdata(intf);
1660 	int cnt;
1661 
1662 	spin_lock_irq(&acm->write_lock);
1663 	if (PMSG_IS_AUTO(message)) {
1664 		if (acm->transmitting) {
1665 			spin_unlock_irq(&acm->write_lock);
1666 			return -EBUSY;
1667 		}
1668 	}
1669 	cnt = acm->susp_count++;
1670 	spin_unlock_irq(&acm->write_lock);
1671 
1672 	if (cnt)
1673 		return 0;
1674 
1675 	acm_poison_urbs(acm);
1676 	cancel_delayed_work_sync(&acm->dwork);
1677 	acm->urbs_in_error_delay = 0;
1678 
1679 	return 0;
1680 }
1681 
1682 static int acm_resume(struct usb_interface *intf)
1683 {
1684 	struct acm *acm = usb_get_intfdata(intf);
1685 	struct urb *urb;
1686 	int rv = 0;
1687 
1688 	spin_lock_irq(&acm->write_lock);
1689 
1690 	if (--acm->susp_count)
1691 		goto out;
1692 
1693 	acm_unpoison_urbs(acm);
1694 
1695 	if (tty_port_initialized(&acm->port) || (acm->quirks & ALWAYS_POLL_CTRL)) {
1696 		rv = usb_submit_urb(acm->ctrlurb, GFP_ATOMIC);
1697 
1698 		for (;;) {
1699 			urb = usb_get_from_anchor(&acm->delayed);
1700 			if (!urb)
1701 				break;
1702 
1703 			acm_start_wb(acm, urb->context);
1704 		}
1705 
1706 		/*
1707 		 * delayed error checking because we must
1708 		 * do the write path at all cost
1709 		 */
1710 		if (rv < 0)
1711 			goto out;
1712 
1713 		rv = acm_submit_read_urbs(acm, GFP_ATOMIC);
1714 	}
1715 out:
1716 	spin_unlock_irq(&acm->write_lock);
1717 
1718 	return rv;
1719 }
1720 
1721 static int acm_reset_resume(struct usb_interface *intf)
1722 {
1723 	struct acm *acm = usb_get_intfdata(intf);
1724 
1725 	if (tty_port_initialized(&acm->port))
1726 		tty_port_tty_hangup(&acm->port, false);
1727 
1728 	return acm_resume(intf);
1729 }
1730 
1731 #endif /* CONFIG_PM */
1732 
1733 static int acm_pre_reset(struct usb_interface *intf)
1734 {
1735 	struct acm *acm = usb_get_intfdata(intf);
1736 
1737 	clear_bit(EVENT_RX_STALL, &acm->flags);
1738 	acm->nb_index = 0; /* pending control transfers are lost */
1739 
1740 	return 0;
1741 }
1742 
1743 #define NOKIA_PCSUITE_ACM_INFO(x) \
1744 		USB_DEVICE_AND_INTERFACE_INFO(0x0421, x, \
1745 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1746 		USB_CDC_ACM_PROTO_VENDOR)
1747 
1748 #define SAMSUNG_PCSUITE_ACM_INFO(x) \
1749 		USB_DEVICE_AND_INTERFACE_INFO(0x04e7, x, \
1750 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1751 		USB_CDC_ACM_PROTO_VENDOR)
1752 
1753 /*
1754  * USB driver structure.
1755  */
1756 
1757 static const struct usb_device_id acm_ids[] = {
1758 	/* quirky and broken devices */
1759 	{ USB_DEVICE(0x0424, 0x274e), /* Microchip Technology, Inc. (formerly SMSC) */
1760 	  .driver_info = DISABLE_ECHO, }, /* DISABLE ECHO in termios flag */
1761 	{ USB_DEVICE(0x076d, 0x0006), /* Denso Cradle CU-321 */
1762 	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
1763 	{ USB_DEVICE(0x17ef, 0x7000), /* Lenovo USB modem */
1764 	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
1765 	{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
1766 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1767 	},
1768 	{ USB_DEVICE(0x045b, 0x023c),	/* Renesas R-Car H3 USB Download mode */
1769 	.driver_info = DISABLE_ECHO,	/* Don't echo banner */
1770 	},
1771 	{ USB_DEVICE(0x045b, 0x0247),	/* Renesas R-Car D3 USB Download mode */
1772 	.driver_info = DISABLE_ECHO,	/* Don't echo banner */
1773 	},
1774 	{ USB_DEVICE(0x045b, 0x0248),	/* Renesas R-Car M3-N USB Download mode */
1775 	.driver_info = DISABLE_ECHO,	/* Don't echo banner */
1776 	},
1777 	{ USB_DEVICE(0x045b, 0x024D),	/* Renesas R-Car E3 USB Download mode */
1778 	.driver_info = DISABLE_ECHO,	/* Don't echo banner */
1779 	},
1780 	{ USB_DEVICE(0x04b8, 0x0d12),	/* EPSON HMD Com&Sens */
1781 	.driver_info = NO_UNION_12,	/* union descriptor is garbage */
1782 	},
1783 	{ USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; andrey.arapov@gmail.com */
1784 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1785 	},
1786 	{ USB_DEVICE(0x0e8d, 0x2000), /* MediaTek Inc Preloader */
1787 	.driver_info = DISABLE_ECHO, /* DISABLE ECHO in termios flag */
1788 	},
1789 	{ USB_DEVICE(0x0e8d, 0x3329), /* MediaTek Inc GPS */
1790 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1791 	},
1792 	{ USB_DEVICE(0x0482, 0x0203), /* KYOCERA AH-K3001V */
1793 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1794 	},
1795 	{ USB_DEVICE(0x079b, 0x000f), /* BT On-Air USB MODEM */
1796 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1797 	},
1798 	{ USB_DEVICE(0x0ace, 0x1602), /* ZyDAS 56K USB MODEM */
1799 	.driver_info = SINGLE_RX_URB,
1800 	},
1801 	{ USB_DEVICE(0x0ace, 0x1608), /* ZyDAS 56K USB MODEM */
1802 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1803 	},
1804 	{ USB_DEVICE(0x0ace, 0x1611), /* ZyDAS 56K USB MODEM - new version */
1805 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1806 	},
1807 	{ USB_DEVICE(0x11ca, 0x0201), /* VeriFone Mx870 Gadget Serial */
1808 	.driver_info = SINGLE_RX_URB,
1809 	},
1810 	{ USB_DEVICE(0x1901, 0x0006), /* GE Healthcare Patient Monitor UI Controller */
1811 	.driver_info = DISABLE_ECHO, /* DISABLE ECHO in termios flag */
1812 	},
1813 	{ USB_DEVICE(0x1965, 0x0018), /* Uniden UBC125XLT */
1814 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1815 	},
1816 	{ USB_DEVICE(0x22b8, 0x7000), /* Motorola Q Phone */
1817 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1818 	},
1819 	{ USB_DEVICE(0x0803, 0x3095), /* Zoom Telephonics Model 3095F USB MODEM */
1820 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1821 	},
1822 	{ USB_DEVICE(0x0572, 0x1321), /* Conexant USB MODEM CX93010 */
1823 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1824 	},
1825 	{ USB_DEVICE(0x0572, 0x1324), /* Conexant USB MODEM RD02-D400 */
1826 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1827 	},
1828 	{ USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */
1829 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1830 	},
1831 	{ USB_DEVICE(0x0572, 0x1349), /* Hiro (Conexant) USB MODEM H50228 */
1832 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1833 	},
1834 	{ USB_DEVICE(0x20df, 0x0001), /* Simtec Electronics Entropy Key */
1835 	.driver_info = QUIRK_CONTROL_LINE_STATE, },
1836 	{ USB_DEVICE(0x2184, 0x001c) },	/* GW Instek AFG-2225 */
1837 	{ USB_DEVICE(0x2184, 0x0036) },	/* GW Instek AFG-125 */
1838 	{ USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
1839 	},
1840 	/* Motorola H24 HSPA module: */
1841 	{ USB_DEVICE(0x22b8, 0x2d91) }, /* modem                                */
1842 	{ USB_DEVICE(0x22b8, 0x2d92),   /* modem           + diagnostics        */
1843 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1844 	},
1845 	{ USB_DEVICE(0x22b8, 0x2d93),   /* modem + AT port                      */
1846 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1847 	},
1848 	{ USB_DEVICE(0x22b8, 0x2d95),   /* modem + AT port + diagnostics        */
1849 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1850 	},
1851 	{ USB_DEVICE(0x22b8, 0x2d96),   /* modem                         + NMEA */
1852 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1853 	},
1854 	{ USB_DEVICE(0x22b8, 0x2d97),   /* modem           + diagnostics + NMEA */
1855 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1856 	},
1857 	{ USB_DEVICE(0x22b8, 0x2d99),   /* modem + AT port               + NMEA */
1858 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1859 	},
1860 	{ USB_DEVICE(0x22b8, 0x2d9a),   /* modem + AT port + diagnostics + NMEA */
1861 	.driver_info = NO_UNION_NORMAL, /* handle only modem interface          */
1862 	},
1863 
1864 	{ USB_DEVICE(0x0572, 0x1329), /* Hummingbird huc56s (Conexant) */
1865 	.driver_info = NO_UNION_NORMAL, /* union descriptor misplaced on
1866 					   data interface instead of
1867 					   communications interface.
1868 					   Maybe we should define a new
1869 					   quirk for this. */
1870 	},
1871 	{ USB_DEVICE(0x0572, 0x1340), /* Conexant CX93010-2x UCMxx */
1872 	.driver_info = NO_UNION_NORMAL,
1873 	},
1874 	{ USB_DEVICE(0x05f9, 0x4002), /* PSC Scanning, Magellan 800i */
1875 	.driver_info = NO_UNION_NORMAL,
1876 	},
1877 	{ USB_DEVICE(0x1bbb, 0x0003), /* Alcatel OT-I650 */
1878 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1879 	},
1880 	{ USB_DEVICE(0x1576, 0x03b1), /* Maretron USB100 */
1881 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1882 	},
1883 	{ USB_DEVICE(0xfff0, 0x0100), /* DATECS FP-2000 */
1884 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1885 	},
1886 	{ USB_DEVICE(0x09d8, 0x0320), /* Elatec GmbH TWN3 */
1887 	.driver_info = NO_UNION_NORMAL, /* has misplaced union descriptor */
1888 	},
1889 	{ USB_DEVICE(0x0c26, 0x0020), /* Icom ICF3400 Serie */
1890 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1891 	},
1892 	{ USB_DEVICE(0x0ca6, 0xa050), /* Castles VEGA3000 */
1893 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1894 	},
1895 
1896 	{ USB_DEVICE(0x2912, 0x0001), /* ATOL FPrint */
1897 	.driver_info = CLEAR_HALT_CONDITIONS,
1898 	},
1899 
1900 	/* Nokia S60 phones expose two ACM channels. The first is
1901 	 * a modem and is picked up by the standard AT-command
1902 	 * information below. The second is 'vendor-specific' but
1903 	 * is treated as a serial device at the S60 end, so we want
1904 	 * to expose it on Linux too. */
1905 	{ NOKIA_PCSUITE_ACM_INFO(0x042D), }, /* Nokia 3250 */
1906 	{ NOKIA_PCSUITE_ACM_INFO(0x04D8), }, /* Nokia 5500 Sport */
1907 	{ NOKIA_PCSUITE_ACM_INFO(0x04C9), }, /* Nokia E50 */
1908 	{ NOKIA_PCSUITE_ACM_INFO(0x0419), }, /* Nokia E60 */
1909 	{ NOKIA_PCSUITE_ACM_INFO(0x044D), }, /* Nokia E61 */
1910 	{ NOKIA_PCSUITE_ACM_INFO(0x0001), }, /* Nokia E61i */
1911 	{ NOKIA_PCSUITE_ACM_INFO(0x0475), }, /* Nokia E62 */
1912 	{ NOKIA_PCSUITE_ACM_INFO(0x0508), }, /* Nokia E65 */
1913 	{ NOKIA_PCSUITE_ACM_INFO(0x0418), }, /* Nokia E70 */
1914 	{ NOKIA_PCSUITE_ACM_INFO(0x0425), }, /* Nokia N71 */
1915 	{ NOKIA_PCSUITE_ACM_INFO(0x0486), }, /* Nokia N73 */
1916 	{ NOKIA_PCSUITE_ACM_INFO(0x04DF), }, /* Nokia N75 */
1917 	{ NOKIA_PCSUITE_ACM_INFO(0x000e), }, /* Nokia N77 */
1918 	{ NOKIA_PCSUITE_ACM_INFO(0x0445), }, /* Nokia N80 */
1919 	{ NOKIA_PCSUITE_ACM_INFO(0x042F), }, /* Nokia N91 & N91 8GB */
1920 	{ NOKIA_PCSUITE_ACM_INFO(0x048E), }, /* Nokia N92 */
1921 	{ NOKIA_PCSUITE_ACM_INFO(0x0420), }, /* Nokia N93 */
1922 	{ NOKIA_PCSUITE_ACM_INFO(0x04E6), }, /* Nokia N93i  */
1923 	{ NOKIA_PCSUITE_ACM_INFO(0x04B2), }, /* Nokia 5700 XpressMusic */
1924 	{ NOKIA_PCSUITE_ACM_INFO(0x0134), }, /* Nokia 6110 Navigator (China) */
1925 	{ NOKIA_PCSUITE_ACM_INFO(0x046E), }, /* Nokia 6110 Navigator */
1926 	{ NOKIA_PCSUITE_ACM_INFO(0x002f), }, /* Nokia 6120 classic &  */
1927 	{ NOKIA_PCSUITE_ACM_INFO(0x0088), }, /* Nokia 6121 classic */
1928 	{ NOKIA_PCSUITE_ACM_INFO(0x00fc), }, /* Nokia 6124 classic */
1929 	{ NOKIA_PCSUITE_ACM_INFO(0x0042), }, /* Nokia E51 */
1930 	{ NOKIA_PCSUITE_ACM_INFO(0x00b0), }, /* Nokia E66 */
1931 	{ NOKIA_PCSUITE_ACM_INFO(0x00ab), }, /* Nokia E71 */
1932 	{ NOKIA_PCSUITE_ACM_INFO(0x0481), }, /* Nokia N76 */
1933 	{ NOKIA_PCSUITE_ACM_INFO(0x0007), }, /* Nokia N81 & N81 8GB */
1934 	{ NOKIA_PCSUITE_ACM_INFO(0x0071), }, /* Nokia N82 */
1935 	{ NOKIA_PCSUITE_ACM_INFO(0x04F0), }, /* Nokia N95 & N95-3 NAM */
1936 	{ NOKIA_PCSUITE_ACM_INFO(0x0070), }, /* Nokia N95 8GB  */
1937 	{ NOKIA_PCSUITE_ACM_INFO(0x0099), }, /* Nokia 6210 Navigator, RM-367 */
1938 	{ NOKIA_PCSUITE_ACM_INFO(0x0128), }, /* Nokia 6210 Navigator, RM-419 */
1939 	{ NOKIA_PCSUITE_ACM_INFO(0x008f), }, /* Nokia 6220 Classic */
1940 	{ NOKIA_PCSUITE_ACM_INFO(0x00a0), }, /* Nokia 6650 */
1941 	{ NOKIA_PCSUITE_ACM_INFO(0x007b), }, /* Nokia N78 */
1942 	{ NOKIA_PCSUITE_ACM_INFO(0x0094), }, /* Nokia N85 */
1943 	{ NOKIA_PCSUITE_ACM_INFO(0x003a), }, /* Nokia N96 & N96-3  */
1944 	{ NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1945 	{ NOKIA_PCSUITE_ACM_INFO(0x0108), }, /* Nokia 5320 XpressMusic 2G */
1946 	{ NOKIA_PCSUITE_ACM_INFO(0x01f5), }, /* Nokia N97, RM-505 */
1947 	{ NOKIA_PCSUITE_ACM_INFO(0x02e3), }, /* Nokia 5230, RM-588 */
1948 	{ NOKIA_PCSUITE_ACM_INFO(0x0178), }, /* Nokia E63 */
1949 	{ NOKIA_PCSUITE_ACM_INFO(0x010e), }, /* Nokia E75 */
1950 	{ NOKIA_PCSUITE_ACM_INFO(0x02d9), }, /* Nokia 6760 Slide */
1951 	{ NOKIA_PCSUITE_ACM_INFO(0x01d0), }, /* Nokia E52 */
1952 	{ NOKIA_PCSUITE_ACM_INFO(0x0223), }, /* Nokia E72 */
1953 	{ NOKIA_PCSUITE_ACM_INFO(0x0275), }, /* Nokia X6 */
1954 	{ NOKIA_PCSUITE_ACM_INFO(0x026c), }, /* Nokia N97 Mini */
1955 	{ NOKIA_PCSUITE_ACM_INFO(0x0154), }, /* Nokia 5800 XpressMusic */
1956 	{ NOKIA_PCSUITE_ACM_INFO(0x04ce), }, /* Nokia E90 */
1957 	{ NOKIA_PCSUITE_ACM_INFO(0x01d4), }, /* Nokia E55 */
1958 	{ NOKIA_PCSUITE_ACM_INFO(0x0302), }, /* Nokia N8 */
1959 	{ NOKIA_PCSUITE_ACM_INFO(0x0335), }, /* Nokia E7 */
1960 	{ NOKIA_PCSUITE_ACM_INFO(0x03cd), }, /* Nokia C7 */
1961 	{ SAMSUNG_PCSUITE_ACM_INFO(0x6651), }, /* Samsung GTi8510 (INNOV8) */
1962 
1963 	/* Support for Owen devices */
1964 	{ USB_DEVICE(0x03eb, 0x0030), }, /* Owen SI30 */
1965 
1966 	/* NOTE: non-Nokia COMM/ACM/0xff is likely MSFT RNDIS... NOT a modem! */
1967 
1968 #if IS_ENABLED(CONFIG_INPUT_IMS_PCU)
1969 	{ USB_DEVICE(0x04d8, 0x0082),	/* Application mode */
1970 	.driver_info = IGNORE_DEVICE,
1971 	},
1972 	{ USB_DEVICE(0x04d8, 0x0083),	/* Bootloader mode */
1973 	.driver_info = IGNORE_DEVICE,
1974 	},
1975 #endif
1976 
1977 #if IS_ENABLED(CONFIG_IR_TOY)
1978 	{ USB_DEVICE(0x04d8, 0xfd08),
1979 	.driver_info = IGNORE_DEVICE,
1980 	},
1981 
1982 	{ USB_DEVICE(0x04d8, 0xf58b),
1983 	.driver_info = IGNORE_DEVICE,
1984 	},
1985 #endif
1986 
1987 #if IS_ENABLED(CONFIG_USB_SERIAL_XR)
1988 	{ USB_DEVICE(0x04e2, 0x1400), .driver_info = IGNORE_DEVICE },
1989 	{ USB_DEVICE(0x04e2, 0x1401), .driver_info = IGNORE_DEVICE },
1990 	{ USB_DEVICE(0x04e2, 0x1402), .driver_info = IGNORE_DEVICE },
1991 	{ USB_DEVICE(0x04e2, 0x1403), .driver_info = IGNORE_DEVICE },
1992 	{ USB_DEVICE(0x04e2, 0x1410), .driver_info = IGNORE_DEVICE },
1993 	{ USB_DEVICE(0x04e2, 0x1411), .driver_info = IGNORE_DEVICE },
1994 	{ USB_DEVICE(0x04e2, 0x1412), .driver_info = IGNORE_DEVICE },
1995 	{ USB_DEVICE(0x04e2, 0x1414), .driver_info = IGNORE_DEVICE },
1996 	{ USB_DEVICE(0x04e2, 0x1420), .driver_info = IGNORE_DEVICE },
1997 	{ USB_DEVICE(0x04e2, 0x1422), .driver_info = IGNORE_DEVICE },
1998 	{ USB_DEVICE(0x04e2, 0x1424), .driver_info = IGNORE_DEVICE },
1999 #endif
2000 
2001 	/*Samsung phone in firmware update mode */
2002 	{ USB_DEVICE(0x04e8, 0x685d),
2003 	.driver_info = IGNORE_DEVICE,
2004 	},
2005 
2006 	/* Exclude Infineon Flash Loader utility */
2007 	{ USB_DEVICE(0x058b, 0x0041),
2008 	.driver_info = IGNORE_DEVICE,
2009 	},
2010 
2011 	/* Exclude ETAS ES58x */
2012 	{ USB_DEVICE(0x108c, 0x0159), /* ES581.4 */
2013 	.driver_info = IGNORE_DEVICE,
2014 	},
2015 	{ USB_DEVICE(0x108c, 0x0168), /* ES582.1 */
2016 	.driver_info = IGNORE_DEVICE,
2017 	},
2018 	{ USB_DEVICE(0x108c, 0x0169), /* ES584.1 */
2019 	.driver_info = IGNORE_DEVICE,
2020 	},
2021 
2022 	{ USB_DEVICE(0x1bc7, 0x0021), /* Telit 3G ACM only composition */
2023 	.driver_info = SEND_ZERO_PACKET,
2024 	},
2025 	{ USB_DEVICE(0x1bc7, 0x0023), /* Telit 3G ACM + ECM composition */
2026 	.driver_info = SEND_ZERO_PACKET,
2027 	},
2028 
2029 	/* Exclude Goodix Fingerprint Reader */
2030 	{ USB_DEVICE(0x27c6, 0x5395),
2031 	.driver_info = IGNORE_DEVICE,
2032 	},
2033 
2034 	/* Exclude Heimann Sensor GmbH USB appset demo */
2035 	{ USB_DEVICE(0x32a7, 0x0000),
2036 	.driver_info = IGNORE_DEVICE,
2037 	},
2038 
2039 	/* CH343 supports CAP_BRK, but doesn't advertise it */
2040 	{ USB_DEVICE(0x1a86, 0x55d3), .driver_info = MISSING_CAP_BRK, },
2041 
2042 	/*
2043 	 * Lenovo Yoga Book 9 14IAH10 (83KJ) — INGENIC 17EF:6161 touchscreen
2044 	 * composite device.  The CDC ACM control interface (0) uses a standard
2045 	 * Union descriptor, but the data interface (1) is declared as vendor-
2046 	 * specific class (0xff) with no CDC data descriptors, so cdc-acm would
2047 	 * normally reject it.  The firmware also requires continuous polling of
2048 	 * the notification endpoint (EP 0x82) to suppress a 20-second watchdog
2049 	 * reset; ALWAYS_POLL_CTRL keeps the ctrlurb active even when no TTY is
2050 	 * open.  Match only the control interface by class to avoid probing the
2051 	 * vendor-specific data interface.
2052 	 */
2053 	{ USB_DEVICE_INTERFACE_CLASS(0x17ef, 0x6161, USB_CLASS_COMM),
2054 	  .driver_info = VENDOR_CLASS_DATA_IFACE | ALWAYS_POLL_CTRL },
2055 
2056 	/* control interfaces without any protocol set */
2057 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
2058 		USB_CDC_PROTO_NONE) },
2059 
2060 	/* control interfaces with various AT-command sets */
2061 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
2062 		USB_CDC_ACM_PROTO_AT_V25TER) },
2063 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
2064 		USB_CDC_ACM_PROTO_AT_PCCA101) },
2065 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
2066 		USB_CDC_ACM_PROTO_AT_PCCA101_WAKE) },
2067 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
2068 		USB_CDC_ACM_PROTO_AT_GSM) },
2069 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
2070 		USB_CDC_ACM_PROTO_AT_3G) },
2071 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
2072 		USB_CDC_ACM_PROTO_AT_CDMA) },
2073 
2074 	{ USB_DEVICE(0x1519, 0x0452), /* Intel 7260 modem */
2075 	.driver_info = SEND_ZERO_PACKET,
2076 	},
2077 
2078 	{ }
2079 };
2080 
2081 MODULE_DEVICE_TABLE(usb, acm_ids);
2082 
2083 static struct usb_driver acm_driver = {
2084 	.name =		"cdc_acm",
2085 	.probe =	acm_probe,
2086 	.disconnect =	acm_disconnect,
2087 #ifdef CONFIG_PM
2088 	.suspend =	acm_suspend,
2089 	.resume =	acm_resume,
2090 	.reset_resume =	acm_reset_resume,
2091 #endif
2092 	.pre_reset =	acm_pre_reset,
2093 	.id_table =	acm_ids,
2094 #ifdef CONFIG_PM
2095 	.supports_autosuspend = 1,
2096 #endif
2097 	.disable_hub_initiated_lpm = 1,
2098 };
2099 
2100 /*
2101  * TTY driver structures.
2102  */
2103 
2104 static const struct tty_operations acm_ops = {
2105 	.install =		acm_tty_install,
2106 	.open =			acm_tty_open,
2107 	.close =		acm_tty_close,
2108 	.cleanup =		acm_tty_cleanup,
2109 	.hangup =		acm_tty_hangup,
2110 	.write =		acm_tty_write,
2111 	.write_room =		acm_tty_write_room,
2112 	.flush_buffer =		acm_tty_flush_buffer,
2113 	.ioctl =		acm_tty_ioctl,
2114 	.throttle =		acm_tty_throttle,
2115 	.unthrottle =		acm_tty_unthrottle,
2116 	.chars_in_buffer =	acm_tty_chars_in_buffer,
2117 	.break_ctl =		acm_tty_break_ctl,
2118 	.set_termios =		acm_tty_set_termios,
2119 	.tiocmget =		acm_tty_tiocmget,
2120 	.tiocmset =		acm_tty_tiocmset,
2121 	.get_serial =		get_serial_info,
2122 	.set_serial =		set_serial_info,
2123 	.get_icount =		acm_tty_get_icount,
2124 };
2125 
2126 /*
2127  * Init / exit.
2128  */
2129 
2130 static int __init acm_init(void)
2131 {
2132 	int retval;
2133 	acm_tty_driver = tty_alloc_driver(ACM_TTY_MINORS, TTY_DRIVER_REAL_RAW |
2134 			TTY_DRIVER_DYNAMIC_DEV);
2135 	if (IS_ERR(acm_tty_driver))
2136 		return PTR_ERR(acm_tty_driver);
2137 	acm_tty_driver->driver_name = "acm",
2138 	acm_tty_driver->name = "ttyACM",
2139 	acm_tty_driver->major = ACM_TTY_MAJOR,
2140 	acm_tty_driver->minor_start = 0,
2141 	acm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
2142 	acm_tty_driver->subtype = SERIAL_TYPE_NORMAL,
2143 	acm_tty_driver->init_termios = tty_std_termios;
2144 	acm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD |
2145 								HUPCL | CLOCAL;
2146 	tty_set_operations(acm_tty_driver, &acm_ops);
2147 
2148 	retval = tty_register_driver(acm_tty_driver);
2149 	if (retval) {
2150 		tty_driver_kref_put(acm_tty_driver);
2151 		return retval;
2152 	}
2153 
2154 	retval = usb_register(&acm_driver);
2155 	if (retval) {
2156 		tty_unregister_driver(acm_tty_driver);
2157 		tty_driver_kref_put(acm_tty_driver);
2158 		return retval;
2159 	}
2160 
2161 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
2162 
2163 	return 0;
2164 }
2165 
2166 static void __exit acm_exit(void)
2167 {
2168 	usb_deregister(&acm_driver);
2169 	tty_unregister_driver(acm_tty_driver);
2170 	tty_driver_kref_put(acm_tty_driver);
2171 	idr_destroy(&acm_minors);
2172 }
2173 
2174 module_init(acm_init);
2175 module_exit(acm_exit);
2176 
2177 MODULE_AUTHOR(DRIVER_AUTHOR);
2178 MODULE_DESCRIPTION(DRIVER_DESC);
2179 MODULE_LICENSE("GPL");
2180 MODULE_ALIAS_CHARDEV_MAJOR(ACM_TTY_MAJOR);
2181