xref: /openbmc/linux/drivers/usb/class/cdc-acm.c (revision e9e8bcb8)
1 /*
2  * cdc-acm.c
3  *
4  * Copyright (c) 1999 Armin Fuerst	<fuerst@in.tum.de>
5  * Copyright (c) 1999 Pavel Machek	<pavel@ucw.cz>
6  * Copyright (c) 1999 Johannes Erdfelt	<johannes@erdfelt.com>
7  * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
8  * Copyright (c) 2004 Oliver Neukum	<oliver@neukum.name>
9  * Copyright (c) 2005 David Kubicek	<dave@awk.cz>
10  * Copyright (c) 2011 Johan Hovold	<jhovold@gmail.com>
11  *
12  * USB Abstract Control Model driver for USB modems and ISDN adapters
13  *
14  * Sponsored by SuSE
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License as published by
18  * the Free Software Foundation; either version 2 of the License, or
19  * (at your option) any later version.
20  *
21  * This program is distributed in the hope that it will be useful,
22  * but WITHOUT ANY WARRANTY; without even the implied warranty of
23  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
24  * GNU General Public License for more details.
25  *
26  * You should have received a copy of the GNU General Public License
27  * along with this program; if not, write to the Free Software
28  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
29  */
30 
31 #undef DEBUG
32 #undef VERBOSE_DEBUG
33 
34 #include <linux/kernel.h>
35 #include <linux/errno.h>
36 #include <linux/init.h>
37 #include <linux/slab.h>
38 #include <linux/tty.h>
39 #include <linux/serial.h>
40 #include <linux/tty_driver.h>
41 #include <linux/tty_flip.h>
42 #include <linux/module.h>
43 #include <linux/mutex.h>
44 #include <linux/uaccess.h>
45 #include <linux/usb.h>
46 #include <linux/usb/cdc.h>
47 #include <asm/byteorder.h>
48 #include <asm/unaligned.h>
49 #include <linux/list.h>
50 
51 #include "cdc-acm.h"
52 
53 
54 #define DRIVER_AUTHOR "Armin Fuerst, Pavel Machek, Johannes Erdfelt, Vojtech Pavlik, David Kubicek, Johan Hovold"
55 #define DRIVER_DESC "USB Abstract Control Model driver for USB modems and ISDN adapters"
56 
57 static struct usb_driver acm_driver;
58 static struct tty_driver *acm_tty_driver;
59 static struct acm *acm_table[ACM_TTY_MINORS];
60 
61 static DEFINE_MUTEX(open_mutex);
62 
63 #define ACM_READY(acm)	(acm && acm->dev && acm->port.count)
64 
65 static const struct tty_port_operations acm_port_ops = {
66 };
67 
68 /*
69  * Functions for ACM control messages.
70  */
71 
72 static int acm_ctrl_msg(struct acm *acm, int request, int value,
73 							void *buf, int len)
74 {
75 	int retval = usb_control_msg(acm->dev, usb_sndctrlpipe(acm->dev, 0),
76 		request, USB_RT_ACM, value,
77 		acm->control->altsetting[0].desc.bInterfaceNumber,
78 		buf, len, 5000);
79 	dev_dbg(&acm->control->dev,
80 			"%s - rq 0x%02x, val %#x, len %#x, result %d\n",
81 			__func__, request, value, len, retval);
82 	return retval < 0 ? retval : 0;
83 }
84 
85 /* devices aren't required to support these requests.
86  * the cdc acm descriptor tells whether they do...
87  */
88 #define acm_set_control(acm, control) \
89 	acm_ctrl_msg(acm, USB_CDC_REQ_SET_CONTROL_LINE_STATE, control, NULL, 0)
90 #define acm_set_line(acm, line) \
91 	acm_ctrl_msg(acm, USB_CDC_REQ_SET_LINE_CODING, 0, line, sizeof *(line))
92 #define acm_send_break(acm, ms) \
93 	acm_ctrl_msg(acm, USB_CDC_REQ_SEND_BREAK, ms, NULL, 0)
94 
95 /*
96  * Write buffer management.
97  * All of these assume proper locks taken by the caller.
98  */
99 
100 static int acm_wb_alloc(struct acm *acm)
101 {
102 	int i, wbn;
103 	struct acm_wb *wb;
104 
105 	wbn = 0;
106 	i = 0;
107 	for (;;) {
108 		wb = &acm->wb[wbn];
109 		if (!wb->use) {
110 			wb->use = 1;
111 			return wbn;
112 		}
113 		wbn = (wbn + 1) % ACM_NW;
114 		if (++i >= ACM_NW)
115 			return -1;
116 	}
117 }
118 
119 static int acm_wb_is_avail(struct acm *acm)
120 {
121 	int i, n;
122 	unsigned long flags;
123 
124 	n = ACM_NW;
125 	spin_lock_irqsave(&acm->write_lock, flags);
126 	for (i = 0; i < ACM_NW; i++)
127 		n -= acm->wb[i].use;
128 	spin_unlock_irqrestore(&acm->write_lock, flags);
129 	return n;
130 }
131 
132 /*
133  * Finish write. Caller must hold acm->write_lock
134  */
135 static void acm_write_done(struct acm *acm, struct acm_wb *wb)
136 {
137 	wb->use = 0;
138 	acm->transmitting--;
139 	usb_autopm_put_interface_async(acm->control);
140 }
141 
142 /*
143  * Poke write.
144  *
145  * the caller is responsible for locking
146  */
147 
148 static int acm_start_wb(struct acm *acm, struct acm_wb *wb)
149 {
150 	int rc;
151 
152 	acm->transmitting++;
153 
154 	wb->urb->transfer_buffer = wb->buf;
155 	wb->urb->transfer_dma = wb->dmah;
156 	wb->urb->transfer_buffer_length = wb->len;
157 	wb->urb->dev = acm->dev;
158 
159 	rc = usb_submit_urb(wb->urb, GFP_ATOMIC);
160 	if (rc < 0) {
161 		dev_err(&acm->data->dev,
162 			"%s - usb_submit_urb(write bulk) failed: %d\n",
163 			__func__, rc);
164 		acm_write_done(acm, wb);
165 	}
166 	return rc;
167 }
168 
169 static int acm_write_start(struct acm *acm, int wbn)
170 {
171 	unsigned long flags;
172 	struct acm_wb *wb = &acm->wb[wbn];
173 	int rc;
174 
175 	spin_lock_irqsave(&acm->write_lock, flags);
176 	if (!acm->dev) {
177 		wb->use = 0;
178 		spin_unlock_irqrestore(&acm->write_lock, flags);
179 		return -ENODEV;
180 	}
181 
182 	dev_vdbg(&acm->data->dev, "%s - susp_count %d\n", __func__,
183 							acm->susp_count);
184 	usb_autopm_get_interface_async(acm->control);
185 	if (acm->susp_count) {
186 		if (!acm->delayed_wb)
187 			acm->delayed_wb = wb;
188 		else
189 			usb_autopm_put_interface_async(acm->control);
190 		spin_unlock_irqrestore(&acm->write_lock, flags);
191 		return 0;	/* A white lie */
192 	}
193 	usb_mark_last_busy(acm->dev);
194 
195 	rc = acm_start_wb(acm, wb);
196 	spin_unlock_irqrestore(&acm->write_lock, flags);
197 
198 	return rc;
199 
200 }
201 /*
202  * attributes exported through sysfs
203  */
204 static ssize_t show_caps
205 (struct device *dev, struct device_attribute *attr, char *buf)
206 {
207 	struct usb_interface *intf = to_usb_interface(dev);
208 	struct acm *acm = usb_get_intfdata(intf);
209 
210 	return sprintf(buf, "%d", acm->ctrl_caps);
211 }
212 static DEVICE_ATTR(bmCapabilities, S_IRUGO, show_caps, NULL);
213 
214 static ssize_t show_country_codes
215 (struct device *dev, struct device_attribute *attr, char *buf)
216 {
217 	struct usb_interface *intf = to_usb_interface(dev);
218 	struct acm *acm = usb_get_intfdata(intf);
219 
220 	memcpy(buf, acm->country_codes, acm->country_code_size);
221 	return acm->country_code_size;
222 }
223 
224 static DEVICE_ATTR(wCountryCodes, S_IRUGO, show_country_codes, NULL);
225 
226 static ssize_t show_country_rel_date
227 (struct device *dev, struct device_attribute *attr, char *buf)
228 {
229 	struct usb_interface *intf = to_usb_interface(dev);
230 	struct acm *acm = usb_get_intfdata(intf);
231 
232 	return sprintf(buf, "%d", acm->country_rel_date);
233 }
234 
235 static DEVICE_ATTR(iCountryCodeRelDate, S_IRUGO, show_country_rel_date, NULL);
236 /*
237  * Interrupt handlers for various ACM device responses
238  */
239 
240 /* control interface reports status changes with "interrupt" transfers */
241 static void acm_ctrl_irq(struct urb *urb)
242 {
243 	struct acm *acm = urb->context;
244 	struct usb_cdc_notification *dr = urb->transfer_buffer;
245 	struct tty_struct *tty;
246 	unsigned char *data;
247 	int newctrl;
248 	int retval;
249 	int status = urb->status;
250 
251 	switch (status) {
252 	case 0:
253 		/* success */
254 		break;
255 	case -ECONNRESET:
256 	case -ENOENT:
257 	case -ESHUTDOWN:
258 		/* this urb is terminated, clean up */
259 		dev_dbg(&acm->control->dev,
260 				"%s - urb shutting down with status: %d\n",
261 				__func__, status);
262 		return;
263 	default:
264 		dev_dbg(&acm->control->dev,
265 				"%s - nonzero urb status received: %d\n",
266 				__func__, status);
267 		goto exit;
268 	}
269 
270 	if (!ACM_READY(acm))
271 		goto exit;
272 
273 	usb_mark_last_busy(acm->dev);
274 
275 	data = (unsigned char *)(dr + 1);
276 	switch (dr->bNotificationType) {
277 	case USB_CDC_NOTIFY_NETWORK_CONNECTION:
278 		dev_dbg(&acm->control->dev, "%s - network connection: %d\n",
279 							__func__, dr->wValue);
280 		break;
281 
282 	case USB_CDC_NOTIFY_SERIAL_STATE:
283 		tty = tty_port_tty_get(&acm->port);
284 		newctrl = get_unaligned_le16(data);
285 
286 		if (tty) {
287 			if (!acm->clocal &&
288 				(acm->ctrlin & ~newctrl & ACM_CTRL_DCD)) {
289 				dev_dbg(&acm->control->dev,
290 					"%s - calling hangup\n", __func__);
291 				tty_hangup(tty);
292 			}
293 			tty_kref_put(tty);
294 		}
295 
296 		acm->ctrlin = newctrl;
297 
298 		dev_dbg(&acm->control->dev,
299 			"%s - input control lines: dcd%c dsr%c break%c "
300 			"ring%c framing%c parity%c overrun%c\n",
301 			__func__,
302 			acm->ctrlin & ACM_CTRL_DCD ? '+' : '-',
303 			acm->ctrlin & ACM_CTRL_DSR ? '+' : '-',
304 			acm->ctrlin & ACM_CTRL_BRK ? '+' : '-',
305 			acm->ctrlin & ACM_CTRL_RI  ? '+' : '-',
306 			acm->ctrlin & ACM_CTRL_FRAMING ? '+' : '-',
307 			acm->ctrlin & ACM_CTRL_PARITY ? '+' : '-',
308 			acm->ctrlin & ACM_CTRL_OVERRUN ? '+' : '-');
309 			break;
310 
311 	default:
312 		dev_dbg(&acm->control->dev,
313 			"%s - unknown notification %d received: index %d "
314 			"len %d data0 %d data1 %d\n",
315 			__func__,
316 			dr->bNotificationType, dr->wIndex,
317 			dr->wLength, data[0], data[1]);
318 		break;
319 	}
320 exit:
321 	retval = usb_submit_urb(urb, GFP_ATOMIC);
322 	if (retval)
323 		dev_err(&acm->control->dev, "%s - usb_submit_urb failed: %d\n",
324 							__func__, retval);
325 }
326 
327 static int acm_submit_read_urb(struct acm *acm, int index, gfp_t mem_flags)
328 {
329 	int res;
330 
331 	if (!test_and_clear_bit(index, &acm->read_urbs_free))
332 		return 0;
333 
334 	dev_vdbg(&acm->data->dev, "%s - urb %d\n", __func__, index);
335 
336 	res = usb_submit_urb(acm->read_urbs[index], mem_flags);
337 	if (res) {
338 		if (res != -EPERM) {
339 			dev_err(&acm->data->dev,
340 					"%s - usb_submit_urb failed: %d\n",
341 					__func__, res);
342 		}
343 		set_bit(index, &acm->read_urbs_free);
344 		return res;
345 	}
346 
347 	return 0;
348 }
349 
350 static int acm_submit_read_urbs(struct acm *acm, gfp_t mem_flags)
351 {
352 	int res;
353 	int i;
354 
355 	for (i = 0; i < acm->rx_buflimit; ++i) {
356 		res = acm_submit_read_urb(acm, i, mem_flags);
357 		if (res)
358 			return res;
359 	}
360 
361 	return 0;
362 }
363 
364 static void acm_process_read_urb(struct acm *acm, struct urb *urb)
365 {
366 	struct tty_struct *tty;
367 
368 	if (!urb->actual_length)
369 		return;
370 
371 	tty = tty_port_tty_get(&acm->port);
372 	if (!tty)
373 		return;
374 
375 	tty_insert_flip_string(tty, urb->transfer_buffer, urb->actual_length);
376 	tty_flip_buffer_push(tty);
377 
378 	tty_kref_put(tty);
379 }
380 
381 static void acm_read_bulk_callback(struct urb *urb)
382 {
383 	struct acm_rb *rb = urb->context;
384 	struct acm *acm = rb->instance;
385 	unsigned long flags;
386 
387 	dev_vdbg(&acm->data->dev, "%s - urb %d, len %d\n", __func__,
388 					rb->index, urb->actual_length);
389 	set_bit(rb->index, &acm->read_urbs_free);
390 
391 	if (!acm->dev) {
392 		dev_dbg(&acm->data->dev, "%s - disconnected\n", __func__);
393 		return;
394 	}
395 	usb_mark_last_busy(acm->dev);
396 
397 	if (urb->status) {
398 		dev_dbg(&acm->data->dev, "%s - non-zero urb status: %d\n",
399 							__func__, urb->status);
400 		return;
401 	}
402 	acm_process_read_urb(acm, urb);
403 
404 	/* throttle device if requested by tty */
405 	spin_lock_irqsave(&acm->read_lock, flags);
406 	acm->throttled = acm->throttle_req;
407 	if (!acm->throttled && !acm->susp_count) {
408 		spin_unlock_irqrestore(&acm->read_lock, flags);
409 		acm_submit_read_urb(acm, rb->index, GFP_ATOMIC);
410 	} else {
411 		spin_unlock_irqrestore(&acm->read_lock, flags);
412 	}
413 }
414 
415 /* data interface wrote those outgoing bytes */
416 static void acm_write_bulk(struct urb *urb)
417 {
418 	struct acm_wb *wb = urb->context;
419 	struct acm *acm = wb->instance;
420 	unsigned long flags;
421 
422 	if (urb->status	|| (urb->actual_length != urb->transfer_buffer_length))
423 		dev_vdbg(&acm->data->dev, "%s - len %d/%d, status %d\n",
424 			__func__,
425 			urb->actual_length,
426 			urb->transfer_buffer_length,
427 			urb->status);
428 
429 	spin_lock_irqsave(&acm->write_lock, flags);
430 	acm_write_done(acm, wb);
431 	spin_unlock_irqrestore(&acm->write_lock, flags);
432 	if (ACM_READY(acm))
433 		schedule_work(&acm->work);
434 }
435 
436 static void acm_softint(struct work_struct *work)
437 {
438 	struct acm *acm = container_of(work, struct acm, work);
439 	struct tty_struct *tty;
440 
441 	dev_vdbg(&acm->data->dev, "%s\n", __func__);
442 
443 	if (!ACM_READY(acm))
444 		return;
445 	tty = tty_port_tty_get(&acm->port);
446 	if (!tty)
447 		return;
448 	tty_wakeup(tty);
449 	tty_kref_put(tty);
450 }
451 
452 /*
453  * TTY handlers
454  */
455 
456 static int acm_tty_open(struct tty_struct *tty, struct file *filp)
457 {
458 	struct acm *acm;
459 	int rv = -ENODEV;
460 
461 	mutex_lock(&open_mutex);
462 
463 	acm = acm_table[tty->index];
464 	if (!acm || !acm->dev)
465 		goto out;
466 	else
467 		rv = 0;
468 
469 	dev_dbg(&acm->control->dev, "%s\n", __func__);
470 
471 	set_bit(TTY_NO_WRITE_SPLIT, &tty->flags);
472 
473 	tty->driver_data = acm;
474 	tty_port_tty_set(&acm->port, tty);
475 
476 	if (usb_autopm_get_interface(acm->control) < 0)
477 		goto early_bail;
478 	else
479 		acm->control->needs_remote_wakeup = 1;
480 
481 	mutex_lock(&acm->mutex);
482 	if (acm->port.count++) {
483 		mutex_unlock(&acm->mutex);
484 		usb_autopm_put_interface(acm->control);
485 		goto out;
486 	}
487 
488 	acm->ctrlurb->dev = acm->dev;
489 	if (usb_submit_urb(acm->ctrlurb, GFP_KERNEL)) {
490 		dev_err(&acm->control->dev,
491 			"%s - usb_submit_urb(ctrl irq) failed\n", __func__);
492 		goto bail_out;
493 	}
494 
495 	if (0 > acm_set_control(acm, acm->ctrlout = ACM_CTRL_DTR | ACM_CTRL_RTS) &&
496 	    (acm->ctrl_caps & USB_CDC_CAP_LINE))
497 		goto bail_out;
498 
499 	usb_autopm_put_interface(acm->control);
500 
501 	if (acm_submit_read_urbs(acm, GFP_KERNEL))
502 		goto bail_out;
503 
504 	set_bit(ASYNCB_INITIALIZED, &acm->port.flags);
505 	rv = tty_port_block_til_ready(&acm->port, tty, filp);
506 
507 	mutex_unlock(&acm->mutex);
508 out:
509 	mutex_unlock(&open_mutex);
510 	return rv;
511 
512 bail_out:
513 	acm->port.count--;
514 	mutex_unlock(&acm->mutex);
515 	usb_autopm_put_interface(acm->control);
516 early_bail:
517 	mutex_unlock(&open_mutex);
518 	tty_port_tty_set(&acm->port, NULL);
519 	return -EIO;
520 }
521 
522 static void acm_tty_unregister(struct acm *acm)
523 {
524 	int i;
525 
526 	tty_unregister_device(acm_tty_driver, acm->minor);
527 	usb_put_intf(acm->control);
528 	acm_table[acm->minor] = NULL;
529 	usb_free_urb(acm->ctrlurb);
530 	for (i = 0; i < ACM_NW; i++)
531 		usb_free_urb(acm->wb[i].urb);
532 	for (i = 0; i < acm->rx_buflimit; i++)
533 		usb_free_urb(acm->read_urbs[i]);
534 	kfree(acm->country_codes);
535 	kfree(acm);
536 }
537 
538 static void acm_port_down(struct acm *acm)
539 {
540 	int i;
541 
542 	mutex_lock(&open_mutex);
543 	if (acm->dev) {
544 		usb_autopm_get_interface(acm->control);
545 		acm_set_control(acm, acm->ctrlout = 0);
546 		usb_kill_urb(acm->ctrlurb);
547 		for (i = 0; i < ACM_NW; i++)
548 			usb_kill_urb(acm->wb[i].urb);
549 		for (i = 0; i < acm->rx_buflimit; i++)
550 			usb_kill_urb(acm->read_urbs[i]);
551 		acm->control->needs_remote_wakeup = 0;
552 		usb_autopm_put_interface(acm->control);
553 	}
554 	mutex_unlock(&open_mutex);
555 }
556 
557 static void acm_tty_hangup(struct tty_struct *tty)
558 {
559 	struct acm *acm = tty->driver_data;
560 	tty_port_hangup(&acm->port);
561 	acm_port_down(acm);
562 }
563 
564 static void acm_tty_close(struct tty_struct *tty, struct file *filp)
565 {
566 	struct acm *acm = tty->driver_data;
567 
568 	/* Perform the closing process and see if we need to do the hardware
569 	   shutdown */
570 	if (!acm)
571 		return;
572 	if (tty_port_close_start(&acm->port, tty, filp) == 0) {
573 		mutex_lock(&open_mutex);
574 		if (!acm->dev) {
575 			tty_port_tty_set(&acm->port, NULL);
576 			acm_tty_unregister(acm);
577 			tty->driver_data = NULL;
578 		}
579 		mutex_unlock(&open_mutex);
580 		return;
581 	}
582 	acm_port_down(acm);
583 	tty_port_close_end(&acm->port, tty);
584 	tty_port_tty_set(&acm->port, NULL);
585 }
586 
587 static int acm_tty_write(struct tty_struct *tty,
588 					const unsigned char *buf, int count)
589 {
590 	struct acm *acm = tty->driver_data;
591 	int stat;
592 	unsigned long flags;
593 	int wbn;
594 	struct acm_wb *wb;
595 
596 	if (!ACM_READY(acm))
597 		return -EINVAL;
598 	if (!count)
599 		return 0;
600 
601 	dev_vdbg(&acm->data->dev, "%s - count %d\n", __func__, count);
602 
603 	spin_lock_irqsave(&acm->write_lock, flags);
604 	wbn = acm_wb_alloc(acm);
605 	if (wbn < 0) {
606 		spin_unlock_irqrestore(&acm->write_lock, flags);
607 		return 0;
608 	}
609 	wb = &acm->wb[wbn];
610 
611 	count = (count > acm->writesize) ? acm->writesize : count;
612 	dev_vdbg(&acm->data->dev, "%s - write %d\n", __func__, count);
613 	memcpy(wb->buf, buf, count);
614 	wb->len = count;
615 	spin_unlock_irqrestore(&acm->write_lock, flags);
616 
617 	stat = acm_write_start(acm, wbn);
618 	if (stat < 0)
619 		return stat;
620 	return count;
621 }
622 
623 static int acm_tty_write_room(struct tty_struct *tty)
624 {
625 	struct acm *acm = tty->driver_data;
626 	if (!ACM_READY(acm))
627 		return -EINVAL;
628 	/*
629 	 * Do not let the line discipline to know that we have a reserve,
630 	 * or it might get too enthusiastic.
631 	 */
632 	return acm_wb_is_avail(acm) ? acm->writesize : 0;
633 }
634 
635 static int acm_tty_chars_in_buffer(struct tty_struct *tty)
636 {
637 	struct acm *acm = tty->driver_data;
638 	if (!ACM_READY(acm))
639 		return 0;
640 	/*
641 	 * This is inaccurate (overcounts), but it works.
642 	 */
643 	return (ACM_NW - acm_wb_is_avail(acm)) * acm->writesize;
644 }
645 
646 static void acm_tty_throttle(struct tty_struct *tty)
647 {
648 	struct acm *acm = tty->driver_data;
649 
650 	if (!ACM_READY(acm))
651 		return;
652 
653 	spin_lock_irq(&acm->read_lock);
654 	acm->throttle_req = 1;
655 	spin_unlock_irq(&acm->read_lock);
656 }
657 
658 static void acm_tty_unthrottle(struct tty_struct *tty)
659 {
660 	struct acm *acm = tty->driver_data;
661 	unsigned int was_throttled;
662 
663 	if (!ACM_READY(acm))
664 		return;
665 
666 	spin_lock_irq(&acm->read_lock);
667 	was_throttled = acm->throttled;
668 	acm->throttled = 0;
669 	acm->throttle_req = 0;
670 	spin_unlock_irq(&acm->read_lock);
671 
672 	if (was_throttled)
673 		acm_submit_read_urbs(acm, GFP_KERNEL);
674 }
675 
676 static int acm_tty_break_ctl(struct tty_struct *tty, int state)
677 {
678 	struct acm *acm = tty->driver_data;
679 	int retval;
680 	if (!ACM_READY(acm))
681 		return -EINVAL;
682 	retval = acm_send_break(acm, state ? 0xffff : 0);
683 	if (retval < 0)
684 		dev_dbg(&acm->control->dev, "%s - send break failed\n",
685 								__func__);
686 	return retval;
687 }
688 
689 static int acm_tty_tiocmget(struct tty_struct *tty)
690 {
691 	struct acm *acm = tty->driver_data;
692 
693 	if (!ACM_READY(acm))
694 		return -EINVAL;
695 
696 	return (acm->ctrlout & ACM_CTRL_DTR ? TIOCM_DTR : 0) |
697 	       (acm->ctrlout & ACM_CTRL_RTS ? TIOCM_RTS : 0) |
698 	       (acm->ctrlin  & ACM_CTRL_DSR ? TIOCM_DSR : 0) |
699 	       (acm->ctrlin  & ACM_CTRL_RI  ? TIOCM_RI  : 0) |
700 	       (acm->ctrlin  & ACM_CTRL_DCD ? TIOCM_CD  : 0) |
701 	       TIOCM_CTS;
702 }
703 
704 static int acm_tty_tiocmset(struct tty_struct *tty,
705 			    unsigned int set, unsigned int clear)
706 {
707 	struct acm *acm = tty->driver_data;
708 	unsigned int newctrl;
709 
710 	if (!ACM_READY(acm))
711 		return -EINVAL;
712 
713 	newctrl = acm->ctrlout;
714 	set = (set & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
715 					(set & TIOCM_RTS ? ACM_CTRL_RTS : 0);
716 	clear = (clear & TIOCM_DTR ? ACM_CTRL_DTR : 0) |
717 					(clear & TIOCM_RTS ? ACM_CTRL_RTS : 0);
718 
719 	newctrl = (newctrl & ~clear) | set;
720 
721 	if (acm->ctrlout == newctrl)
722 		return 0;
723 	return acm_set_control(acm, acm->ctrlout = newctrl);
724 }
725 
726 static int acm_tty_ioctl(struct tty_struct *tty,
727 					unsigned int cmd, unsigned long arg)
728 {
729 	struct acm *acm = tty->driver_data;
730 
731 	if (!ACM_READY(acm))
732 		return -EINVAL;
733 
734 	return -ENOIOCTLCMD;
735 }
736 
737 static const __u32 acm_tty_speed[] = {
738 	0, 50, 75, 110, 134, 150, 200, 300, 600,
739 	1200, 1800, 2400, 4800, 9600, 19200, 38400,
740 	57600, 115200, 230400, 460800, 500000, 576000,
741 	921600, 1000000, 1152000, 1500000, 2000000,
742 	2500000, 3000000, 3500000, 4000000
743 };
744 
745 static const __u8 acm_tty_size[] = {
746 	5, 6, 7, 8
747 };
748 
749 static void acm_tty_set_termios(struct tty_struct *tty,
750 						struct ktermios *termios_old)
751 {
752 	struct acm *acm = tty->driver_data;
753 	struct ktermios *termios = tty->termios;
754 	struct usb_cdc_line_coding newline;
755 	int newctrl = acm->ctrlout;
756 
757 	if (!ACM_READY(acm))
758 		return;
759 
760 	newline.dwDTERate = cpu_to_le32(tty_get_baud_rate(tty));
761 	newline.bCharFormat = termios->c_cflag & CSTOPB ? 2 : 0;
762 	newline.bParityType = termios->c_cflag & PARENB ?
763 				(termios->c_cflag & PARODD ? 1 : 2) +
764 				(termios->c_cflag & CMSPAR ? 2 : 0) : 0;
765 	newline.bDataBits = acm_tty_size[(termios->c_cflag & CSIZE) >> 4];
766 	/* FIXME: Needs to clear unsupported bits in the termios */
767 	acm->clocal = ((termios->c_cflag & CLOCAL) != 0);
768 
769 	if (!newline.dwDTERate) {
770 		newline.dwDTERate = acm->line.dwDTERate;
771 		newctrl &= ~ACM_CTRL_DTR;
772 	} else
773 		newctrl |=  ACM_CTRL_DTR;
774 
775 	if (newctrl != acm->ctrlout)
776 		acm_set_control(acm, acm->ctrlout = newctrl);
777 
778 	if (memcmp(&acm->line, &newline, sizeof newline)) {
779 		memcpy(&acm->line, &newline, sizeof newline);
780 		dev_dbg(&acm->control->dev, "%s - set line: %d %d %d %d\n",
781 			__func__,
782 			le32_to_cpu(newline.dwDTERate),
783 			newline.bCharFormat, newline.bParityType,
784 			newline.bDataBits);
785 		acm_set_line(acm, &acm->line);
786 	}
787 }
788 
789 /*
790  * USB probe and disconnect routines.
791  */
792 
793 /* Little helpers: write/read buffers free */
794 static void acm_write_buffers_free(struct acm *acm)
795 {
796 	int i;
797 	struct acm_wb *wb;
798 	struct usb_device *usb_dev = interface_to_usbdev(acm->control);
799 
800 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++)
801 		usb_free_coherent(usb_dev, acm->writesize, wb->buf, wb->dmah);
802 }
803 
804 static void acm_read_buffers_free(struct acm *acm)
805 {
806 	struct usb_device *usb_dev = interface_to_usbdev(acm->control);
807 	int i;
808 
809 	for (i = 0; i < acm->rx_buflimit; i++)
810 		usb_free_coherent(usb_dev, acm->readsize,
811 			  acm->read_buffers[i].base, acm->read_buffers[i].dma);
812 }
813 
814 /* Little helper: write buffers allocate */
815 static int acm_write_buffers_alloc(struct acm *acm)
816 {
817 	int i;
818 	struct acm_wb *wb;
819 
820 	for (wb = &acm->wb[0], i = 0; i < ACM_NW; i++, wb++) {
821 		wb->buf = usb_alloc_coherent(acm->dev, acm->writesize, GFP_KERNEL,
822 		    &wb->dmah);
823 		if (!wb->buf) {
824 			while (i != 0) {
825 				--i;
826 				--wb;
827 				usb_free_coherent(acm->dev, acm->writesize,
828 				    wb->buf, wb->dmah);
829 			}
830 			return -ENOMEM;
831 		}
832 	}
833 	return 0;
834 }
835 
836 static int acm_probe(struct usb_interface *intf,
837 		     const struct usb_device_id *id)
838 {
839 	struct usb_cdc_union_desc *union_header = NULL;
840 	struct usb_cdc_country_functional_desc *cfd = NULL;
841 	unsigned char *buffer = intf->altsetting->extra;
842 	int buflen = intf->altsetting->extralen;
843 	struct usb_interface *control_interface;
844 	struct usb_interface *data_interface;
845 	struct usb_endpoint_descriptor *epctrl = NULL;
846 	struct usb_endpoint_descriptor *epread = NULL;
847 	struct usb_endpoint_descriptor *epwrite = NULL;
848 	struct usb_device *usb_dev = interface_to_usbdev(intf);
849 	struct acm *acm;
850 	int minor;
851 	int ctrlsize, readsize;
852 	u8 *buf;
853 	u8 ac_management_function = 0;
854 	u8 call_management_function = 0;
855 	int call_interface_num = -1;
856 	int data_interface_num = -1;
857 	unsigned long quirks;
858 	int num_rx_buf;
859 	int i;
860 	int combined_interfaces = 0;
861 
862 	/* normal quirks */
863 	quirks = (unsigned long)id->driver_info;
864 	num_rx_buf = (quirks == SINGLE_RX_URB) ? 1 : ACM_NR;
865 
866 	/* handle quirks deadly to normal probing*/
867 	if (quirks == NO_UNION_NORMAL) {
868 		data_interface = usb_ifnum_to_if(usb_dev, 1);
869 		control_interface = usb_ifnum_to_if(usb_dev, 0);
870 		goto skip_normal_probe;
871 	}
872 
873 	/* normal probing*/
874 	if (!buffer) {
875 		dev_err(&intf->dev, "Weird descriptor references\n");
876 		return -EINVAL;
877 	}
878 
879 	if (!buflen) {
880 		if (intf->cur_altsetting->endpoint &&
881 				intf->cur_altsetting->endpoint->extralen &&
882 				intf->cur_altsetting->endpoint->extra) {
883 			dev_dbg(&intf->dev,
884 				"Seeking extra descriptors on endpoint\n");
885 			buflen = intf->cur_altsetting->endpoint->extralen;
886 			buffer = intf->cur_altsetting->endpoint->extra;
887 		} else {
888 			dev_err(&intf->dev,
889 				"Zero length descriptor references\n");
890 			return -EINVAL;
891 		}
892 	}
893 
894 	while (buflen > 0) {
895 		if (buffer[1] != USB_DT_CS_INTERFACE) {
896 			dev_err(&intf->dev, "skipping garbage\n");
897 			goto next_desc;
898 		}
899 
900 		switch (buffer[2]) {
901 		case USB_CDC_UNION_TYPE: /* we've found it */
902 			if (union_header) {
903 				dev_err(&intf->dev, "More than one "
904 					"union descriptor, skipping ...\n");
905 				goto next_desc;
906 			}
907 			union_header = (struct usb_cdc_union_desc *)buffer;
908 			break;
909 		case USB_CDC_COUNTRY_TYPE: /* export through sysfs*/
910 			cfd = (struct usb_cdc_country_functional_desc *)buffer;
911 			break;
912 		case USB_CDC_HEADER_TYPE: /* maybe check version */
913 			break; /* for now we ignore it */
914 		case USB_CDC_ACM_TYPE:
915 			ac_management_function = buffer[3];
916 			break;
917 		case USB_CDC_CALL_MANAGEMENT_TYPE:
918 			call_management_function = buffer[3];
919 			call_interface_num = buffer[4];
920 			if ( (quirks & NOT_A_MODEM) == 0 && (call_management_function & 3) != 3)
921 				dev_err(&intf->dev, "This device cannot do calls on its own. It is not a modem.\n");
922 			break;
923 		default:
924 			/* there are LOTS more CDC descriptors that
925 			 * could legitimately be found here.
926 			 */
927 			dev_dbg(&intf->dev, "Ignoring descriptor: "
928 					"type %02x, length %d\n",
929 					buffer[2], buffer[0]);
930 			break;
931 		}
932 next_desc:
933 		buflen -= buffer[0];
934 		buffer += buffer[0];
935 	}
936 
937 	if (!union_header) {
938 		if (call_interface_num > 0) {
939 			dev_dbg(&intf->dev, "No union descriptor, using call management descriptor\n");
940 			/* quirks for Droids MuIn LCD */
941 			if (quirks & NO_DATA_INTERFACE)
942 				data_interface = usb_ifnum_to_if(usb_dev, 0);
943 			else
944 				data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = call_interface_num));
945 			control_interface = intf;
946 		} else {
947 			if (intf->cur_altsetting->desc.bNumEndpoints != 3) {
948 				dev_dbg(&intf->dev,"No union descriptor, giving up\n");
949 				return -ENODEV;
950 			} else {
951 				dev_warn(&intf->dev,"No union descriptor, testing for castrated device\n");
952 				combined_interfaces = 1;
953 				control_interface = data_interface = intf;
954 				goto look_for_collapsed_interface;
955 			}
956 		}
957 	} else {
958 		control_interface = usb_ifnum_to_if(usb_dev, union_header->bMasterInterface0);
959 		data_interface = usb_ifnum_to_if(usb_dev, (data_interface_num = union_header->bSlaveInterface0));
960 		if (!control_interface || !data_interface) {
961 			dev_dbg(&intf->dev, "no interfaces\n");
962 			return -ENODEV;
963 		}
964 	}
965 
966 	if (data_interface_num != call_interface_num)
967 		dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");
968 
969 	if (control_interface == data_interface) {
970 		/* some broken devices designed for windows work this way */
971 		dev_warn(&intf->dev,"Control and data interfaces are not separated!\n");
972 		combined_interfaces = 1;
973 		/* a popular other OS doesn't use it */
974 		quirks |= NO_CAP_LINE;
975 		if (data_interface->cur_altsetting->desc.bNumEndpoints != 3) {
976 			dev_err(&intf->dev, "This needs exactly 3 endpoints\n");
977 			return -EINVAL;
978 		}
979 look_for_collapsed_interface:
980 		for (i = 0; i < 3; i++) {
981 			struct usb_endpoint_descriptor *ep;
982 			ep = &data_interface->cur_altsetting->endpoint[i].desc;
983 
984 			if (usb_endpoint_is_int_in(ep))
985 				epctrl = ep;
986 			else if (usb_endpoint_is_bulk_out(ep))
987 				epwrite = ep;
988 			else if (usb_endpoint_is_bulk_in(ep))
989 				epread = ep;
990 			else
991 				return -EINVAL;
992 		}
993 		if (!epctrl || !epread || !epwrite)
994 			return -ENODEV;
995 		else
996 			goto made_compressed_probe;
997 	}
998 
999 skip_normal_probe:
1000 
1001 	/*workaround for switched interfaces */
1002 	if (data_interface->cur_altsetting->desc.bInterfaceClass
1003 						!= CDC_DATA_INTERFACE_TYPE) {
1004 		if (control_interface->cur_altsetting->desc.bInterfaceClass
1005 						== CDC_DATA_INTERFACE_TYPE) {
1006 			struct usb_interface *t;
1007 			dev_dbg(&intf->dev,
1008 				"Your device has switched interfaces.\n");
1009 			t = control_interface;
1010 			control_interface = data_interface;
1011 			data_interface = t;
1012 		} else {
1013 			return -EINVAL;
1014 		}
1015 	}
1016 
1017 	/* Accept probe requests only for the control interface */
1018 	if (!combined_interfaces && intf != control_interface)
1019 		return -ENODEV;
1020 
1021 	if (!combined_interfaces && usb_interface_claimed(data_interface)) {
1022 		/* valid in this context */
1023 		dev_dbg(&intf->dev, "The data interface isn't available\n");
1024 		return -EBUSY;
1025 	}
1026 
1027 
1028 	if (data_interface->cur_altsetting->desc.bNumEndpoints < 2)
1029 		return -EINVAL;
1030 
1031 	epctrl = &control_interface->cur_altsetting->endpoint[0].desc;
1032 	epread = &data_interface->cur_altsetting->endpoint[0].desc;
1033 	epwrite = &data_interface->cur_altsetting->endpoint[1].desc;
1034 
1035 
1036 	/* workaround for switched endpoints */
1037 	if (!usb_endpoint_dir_in(epread)) {
1038 		/* descriptors are swapped */
1039 		struct usb_endpoint_descriptor *t;
1040 		dev_dbg(&intf->dev,
1041 			"The data interface has switched endpoints\n");
1042 		t = epread;
1043 		epread = epwrite;
1044 		epwrite = t;
1045 	}
1046 made_compressed_probe:
1047 	dev_dbg(&intf->dev, "interfaces are valid\n");
1048 	for (minor = 0; minor < ACM_TTY_MINORS && acm_table[minor]; minor++);
1049 
1050 	if (minor == ACM_TTY_MINORS) {
1051 		dev_err(&intf->dev, "no more free acm devices\n");
1052 		return -ENODEV;
1053 	}
1054 
1055 	acm = kzalloc(sizeof(struct acm), GFP_KERNEL);
1056 	if (acm == NULL) {
1057 		dev_err(&intf->dev, "out of memory (acm kzalloc)\n");
1058 		goto alloc_fail;
1059 	}
1060 
1061 	ctrlsize = le16_to_cpu(epctrl->wMaxPacketSize);
1062 	readsize = le16_to_cpu(epread->wMaxPacketSize) *
1063 				(quirks == SINGLE_RX_URB ? 1 : 2);
1064 	acm->combined_interfaces = combined_interfaces;
1065 	acm->writesize = le16_to_cpu(epwrite->wMaxPacketSize) * 20;
1066 	acm->control = control_interface;
1067 	acm->data = data_interface;
1068 	acm->minor = minor;
1069 	acm->dev = usb_dev;
1070 	acm->ctrl_caps = ac_management_function;
1071 	if (quirks & NO_CAP_LINE)
1072 		acm->ctrl_caps &= ~USB_CDC_CAP_LINE;
1073 	acm->ctrlsize = ctrlsize;
1074 	acm->readsize = readsize;
1075 	acm->rx_buflimit = num_rx_buf;
1076 	INIT_WORK(&acm->work, acm_softint);
1077 	spin_lock_init(&acm->write_lock);
1078 	spin_lock_init(&acm->read_lock);
1079 	mutex_init(&acm->mutex);
1080 	acm->rx_endpoint = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
1081 	acm->is_int_ep = usb_endpoint_xfer_int(epread);
1082 	if (acm->is_int_ep)
1083 		acm->bInterval = epread->bInterval;
1084 	tty_port_init(&acm->port);
1085 	acm->port.ops = &acm_port_ops;
1086 
1087 	buf = usb_alloc_coherent(usb_dev, ctrlsize, GFP_KERNEL, &acm->ctrl_dma);
1088 	if (!buf) {
1089 		dev_err(&intf->dev, "out of memory (ctrl buffer alloc)\n");
1090 		goto alloc_fail2;
1091 	}
1092 	acm->ctrl_buffer = buf;
1093 
1094 	if (acm_write_buffers_alloc(acm) < 0) {
1095 		dev_err(&intf->dev, "out of memory (write buffer alloc)\n");
1096 		goto alloc_fail4;
1097 	}
1098 
1099 	acm->ctrlurb = usb_alloc_urb(0, GFP_KERNEL);
1100 	if (!acm->ctrlurb) {
1101 		dev_err(&intf->dev, "out of memory (ctrlurb kmalloc)\n");
1102 		goto alloc_fail5;
1103 	}
1104 	for (i = 0; i < num_rx_buf; i++) {
1105 		struct acm_rb *rb = &(acm->read_buffers[i]);
1106 		struct urb *urb;
1107 
1108 		rb->base = usb_alloc_coherent(acm->dev, readsize, GFP_KERNEL,
1109 								&rb->dma);
1110 		if (!rb->base) {
1111 			dev_err(&intf->dev, "out of memory "
1112 					"(read bufs usb_alloc_coherent)\n");
1113 			goto alloc_fail6;
1114 		}
1115 		rb->index = i;
1116 		rb->instance = acm;
1117 
1118 		urb = usb_alloc_urb(0, GFP_KERNEL);
1119 		if (!urb) {
1120 			dev_err(&intf->dev,
1121 				"out of memory (read urbs usb_alloc_urb)\n");
1122 			goto alloc_fail6;
1123 		}
1124 		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1125 		urb->transfer_dma = rb->dma;
1126 		if (acm->is_int_ep) {
1127 			usb_fill_int_urb(urb, acm->dev,
1128 					 acm->rx_endpoint,
1129 					 rb->base,
1130 					 acm->readsize,
1131 					 acm_read_bulk_callback, rb,
1132 					 acm->bInterval);
1133 		} else {
1134 			usb_fill_bulk_urb(urb, acm->dev,
1135 					  acm->rx_endpoint,
1136 					  rb->base,
1137 					  acm->readsize,
1138 					  acm_read_bulk_callback, rb);
1139 		}
1140 
1141 		acm->read_urbs[i] = urb;
1142 		__set_bit(i, &acm->read_urbs_free);
1143 	}
1144 	for (i = 0; i < ACM_NW; i++) {
1145 		struct acm_wb *snd = &(acm->wb[i]);
1146 
1147 		snd->urb = usb_alloc_urb(0, GFP_KERNEL);
1148 		if (snd->urb == NULL) {
1149 			dev_err(&intf->dev,
1150 				"out of memory (write urbs usb_alloc_urb)\n");
1151 			goto alloc_fail7;
1152 		}
1153 
1154 		if (usb_endpoint_xfer_int(epwrite))
1155 			usb_fill_int_urb(snd->urb, usb_dev,
1156 				usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
1157 				NULL, acm->writesize, acm_write_bulk, snd, epwrite->bInterval);
1158 		else
1159 			usb_fill_bulk_urb(snd->urb, usb_dev,
1160 				usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress),
1161 				NULL, acm->writesize, acm_write_bulk, snd);
1162 		snd->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1163 		snd->instance = acm;
1164 	}
1165 
1166 	usb_set_intfdata(intf, acm);
1167 
1168 	i = device_create_file(&intf->dev, &dev_attr_bmCapabilities);
1169 	if (i < 0)
1170 		goto alloc_fail7;
1171 
1172 	if (cfd) { /* export the country data */
1173 		acm->country_codes = kmalloc(cfd->bLength - 4, GFP_KERNEL);
1174 		if (!acm->country_codes)
1175 			goto skip_countries;
1176 		acm->country_code_size = cfd->bLength - 4;
1177 		memcpy(acm->country_codes, (u8 *)&cfd->wCountyCode0,
1178 							cfd->bLength - 4);
1179 		acm->country_rel_date = cfd->iCountryCodeRelDate;
1180 
1181 		i = device_create_file(&intf->dev, &dev_attr_wCountryCodes);
1182 		if (i < 0) {
1183 			kfree(acm->country_codes);
1184 			goto skip_countries;
1185 		}
1186 
1187 		i = device_create_file(&intf->dev,
1188 						&dev_attr_iCountryCodeRelDate);
1189 		if (i < 0) {
1190 			device_remove_file(&intf->dev, &dev_attr_wCountryCodes);
1191 			kfree(acm->country_codes);
1192 			goto skip_countries;
1193 		}
1194 	}
1195 
1196 skip_countries:
1197 	usb_fill_int_urb(acm->ctrlurb, usb_dev,
1198 			 usb_rcvintpipe(usb_dev, epctrl->bEndpointAddress),
1199 			 acm->ctrl_buffer, ctrlsize, acm_ctrl_irq, acm,
1200 			 /* works around buggy devices */
1201 			 epctrl->bInterval ? epctrl->bInterval : 0xff);
1202 	acm->ctrlurb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1203 	acm->ctrlurb->transfer_dma = acm->ctrl_dma;
1204 
1205 	dev_info(&intf->dev, "ttyACM%d: USB ACM device\n", minor);
1206 
1207 	acm_set_control(acm, acm->ctrlout);
1208 
1209 	acm->line.dwDTERate = cpu_to_le32(9600);
1210 	acm->line.bDataBits = 8;
1211 	acm_set_line(acm, &acm->line);
1212 
1213 	usb_driver_claim_interface(&acm_driver, data_interface, acm);
1214 	usb_set_intfdata(data_interface, acm);
1215 
1216 	usb_get_intf(control_interface);
1217 	tty_register_device(acm_tty_driver, minor, &control_interface->dev);
1218 
1219 	acm_table[minor] = acm;
1220 
1221 	return 0;
1222 alloc_fail7:
1223 	for (i = 0; i < ACM_NW; i++)
1224 		usb_free_urb(acm->wb[i].urb);
1225 alloc_fail6:
1226 	for (i = 0; i < num_rx_buf; i++)
1227 		usb_free_urb(acm->read_urbs[i]);
1228 	acm_read_buffers_free(acm);
1229 	usb_free_urb(acm->ctrlurb);
1230 alloc_fail5:
1231 	acm_write_buffers_free(acm);
1232 alloc_fail4:
1233 	usb_free_coherent(usb_dev, ctrlsize, acm->ctrl_buffer, acm->ctrl_dma);
1234 alloc_fail2:
1235 	kfree(acm);
1236 alloc_fail:
1237 	return -ENOMEM;
1238 }
1239 
1240 static void stop_data_traffic(struct acm *acm)
1241 {
1242 	int i;
1243 
1244 	dev_dbg(&acm->control->dev, "%s\n", __func__);
1245 
1246 	usb_kill_urb(acm->ctrlurb);
1247 	for (i = 0; i < ACM_NW; i++)
1248 		usb_kill_urb(acm->wb[i].urb);
1249 	for (i = 0; i < acm->rx_buflimit; i++)
1250 		usb_kill_urb(acm->read_urbs[i]);
1251 
1252 	cancel_work_sync(&acm->work);
1253 }
1254 
1255 static void acm_disconnect(struct usb_interface *intf)
1256 {
1257 	struct acm *acm = usb_get_intfdata(intf);
1258 	struct usb_device *usb_dev = interface_to_usbdev(intf);
1259 	struct tty_struct *tty;
1260 
1261 	/* sibling interface is already cleaning up */
1262 	if (!acm)
1263 		return;
1264 
1265 	mutex_lock(&open_mutex);
1266 	if (acm->country_codes) {
1267 		device_remove_file(&acm->control->dev,
1268 				&dev_attr_wCountryCodes);
1269 		device_remove_file(&acm->control->dev,
1270 				&dev_attr_iCountryCodeRelDate);
1271 	}
1272 	device_remove_file(&acm->control->dev, &dev_attr_bmCapabilities);
1273 	acm->dev = NULL;
1274 	usb_set_intfdata(acm->control, NULL);
1275 	usb_set_intfdata(acm->data, NULL);
1276 
1277 	stop_data_traffic(acm);
1278 
1279 	acm_write_buffers_free(acm);
1280 	usb_free_coherent(usb_dev, acm->ctrlsize, acm->ctrl_buffer,
1281 			  acm->ctrl_dma);
1282 	acm_read_buffers_free(acm);
1283 
1284 	if (!acm->combined_interfaces)
1285 		usb_driver_release_interface(&acm_driver, intf == acm->control ?
1286 					acm->data : acm->control);
1287 
1288 	if (acm->port.count == 0) {
1289 		acm_tty_unregister(acm);
1290 		mutex_unlock(&open_mutex);
1291 		return;
1292 	}
1293 
1294 	mutex_unlock(&open_mutex);
1295 	tty = tty_port_tty_get(&acm->port);
1296 	if (tty) {
1297 		tty_hangup(tty);
1298 		tty_kref_put(tty);
1299 	}
1300 }
1301 
1302 #ifdef CONFIG_PM
1303 static int acm_suspend(struct usb_interface *intf, pm_message_t message)
1304 {
1305 	struct acm *acm = usb_get_intfdata(intf);
1306 	int cnt;
1307 
1308 	if (message.event & PM_EVENT_AUTO) {
1309 		int b;
1310 
1311 		spin_lock_irq(&acm->write_lock);
1312 		b = acm->transmitting;
1313 		spin_unlock_irq(&acm->write_lock);
1314 		if (b)
1315 			return -EBUSY;
1316 	}
1317 
1318 	spin_lock_irq(&acm->read_lock);
1319 	spin_lock(&acm->write_lock);
1320 	cnt = acm->susp_count++;
1321 	spin_unlock(&acm->write_lock);
1322 	spin_unlock_irq(&acm->read_lock);
1323 
1324 	if (cnt)
1325 		return 0;
1326 	/*
1327 	we treat opened interfaces differently,
1328 	we must guard against open
1329 	*/
1330 	mutex_lock(&acm->mutex);
1331 
1332 	if (acm->port.count)
1333 		stop_data_traffic(acm);
1334 
1335 	mutex_unlock(&acm->mutex);
1336 	return 0;
1337 }
1338 
1339 static int acm_resume(struct usb_interface *intf)
1340 {
1341 	struct acm *acm = usb_get_intfdata(intf);
1342 	struct acm_wb *wb;
1343 	int rv = 0;
1344 	int cnt;
1345 
1346 	spin_lock_irq(&acm->read_lock);
1347 	acm->susp_count -= 1;
1348 	cnt = acm->susp_count;
1349 	spin_unlock_irq(&acm->read_lock);
1350 
1351 	if (cnt)
1352 		return 0;
1353 
1354 	mutex_lock(&acm->mutex);
1355 	if (acm->port.count) {
1356 		rv = usb_submit_urb(acm->ctrlurb, GFP_NOIO);
1357 
1358 		spin_lock_irq(&acm->write_lock);
1359 		if (acm->delayed_wb) {
1360 			wb = acm->delayed_wb;
1361 			acm->delayed_wb = NULL;
1362 			spin_unlock_irq(&acm->write_lock);
1363 			acm_start_wb(acm, wb);
1364 		} else {
1365 			spin_unlock_irq(&acm->write_lock);
1366 		}
1367 
1368 		/*
1369 		 * delayed error checking because we must
1370 		 * do the write path at all cost
1371 		 */
1372 		if (rv < 0)
1373 			goto err_out;
1374 
1375 		rv = acm_submit_read_urbs(acm, GFP_NOIO);
1376 	}
1377 
1378 err_out:
1379 	mutex_unlock(&acm->mutex);
1380 	return rv;
1381 }
1382 
1383 static int acm_reset_resume(struct usb_interface *intf)
1384 {
1385 	struct acm *acm = usb_get_intfdata(intf);
1386 	struct tty_struct *tty;
1387 
1388 	mutex_lock(&acm->mutex);
1389 	if (acm->port.count) {
1390 		tty = tty_port_tty_get(&acm->port);
1391 		if (tty) {
1392 			tty_hangup(tty);
1393 			tty_kref_put(tty);
1394 		}
1395 	}
1396 	mutex_unlock(&acm->mutex);
1397 	return acm_resume(intf);
1398 }
1399 
1400 #endif /* CONFIG_PM */
1401 
1402 #define NOKIA_PCSUITE_ACM_INFO(x) \
1403 		USB_DEVICE_AND_INTERFACE_INFO(0x0421, x, \
1404 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1405 		USB_CDC_ACM_PROTO_VENDOR)
1406 
1407 #define SAMSUNG_PCSUITE_ACM_INFO(x) \
1408 		USB_DEVICE_AND_INTERFACE_INFO(0x04e7, x, \
1409 		USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, \
1410 		USB_CDC_ACM_PROTO_VENDOR)
1411 
1412 /*
1413  * USB driver structure.
1414  */
1415 
1416 static const struct usb_device_id acm_ids[] = {
1417 	/* quirky and broken devices */
1418 	{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
1419 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1420 	},
1421 	{ USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; andrey.arapov@gmail.com */
1422 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1423 	},
1424 	{ USB_DEVICE(0x0e8d, 0x3329), /* MediaTek Inc GPS */
1425 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1426 	},
1427 	{ USB_DEVICE(0x0482, 0x0203), /* KYOCERA AH-K3001V */
1428 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1429 	},
1430 	{ USB_DEVICE(0x079b, 0x000f), /* BT On-Air USB MODEM */
1431 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1432 	},
1433 	{ USB_DEVICE(0x0ace, 0x1602), /* ZyDAS 56K USB MODEM */
1434 	.driver_info = SINGLE_RX_URB,
1435 	},
1436 	{ USB_DEVICE(0x0ace, 0x1608), /* ZyDAS 56K USB MODEM */
1437 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1438 	},
1439 	{ USB_DEVICE(0x0ace, 0x1611), /* ZyDAS 56K USB MODEM - new version */
1440 	.driver_info = SINGLE_RX_URB, /* firmware bug */
1441 	},
1442 	{ USB_DEVICE(0x22b8, 0x7000), /* Motorola Q Phone */
1443 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1444 	},
1445 	{ USB_DEVICE(0x0803, 0x3095), /* Zoom Telephonics Model 3095F USB MODEM */
1446 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1447 	},
1448 	{ USB_DEVICE(0x0572, 0x1321), /* Conexant USB MODEM CX93010 */
1449 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1450 	},
1451 	{ USB_DEVICE(0x0572, 0x1324), /* Conexant USB MODEM RD02-D400 */
1452 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1453 	},
1454 	{ USB_DEVICE(0x0572, 0x1328), /* Shiro / Aztech USB MODEM UM-3100 */
1455 	.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
1456 	},
1457 	{ USB_DEVICE(0x22b8, 0x6425), /* Motorola MOTOMAGX phones */
1458 	},
1459 	{ USB_DEVICE(0x0572, 0x1329), /* Hummingbird huc56s (Conexant) */
1460 	.driver_info = NO_UNION_NORMAL, /* union descriptor misplaced on
1461 					   data interface instead of
1462 					   communications interface.
1463 					   Maybe we should define a new
1464 					   quirk for this. */
1465 	},
1466 	{ USB_DEVICE(0x1bbb, 0x0003), /* Alcatel OT-I650 */
1467 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1468 	},
1469 	{ USB_DEVICE(0x1576, 0x03b1), /* Maretron USB100 */
1470 	.driver_info = NO_UNION_NORMAL, /* reports zero length descriptor */
1471 	},
1472 
1473 	/* Nokia S60 phones expose two ACM channels. The first is
1474 	 * a modem and is picked up by the standard AT-command
1475 	 * information below. The second is 'vendor-specific' but
1476 	 * is treated as a serial device at the S60 end, so we want
1477 	 * to expose it on Linux too. */
1478 	{ NOKIA_PCSUITE_ACM_INFO(0x042D), }, /* Nokia 3250 */
1479 	{ NOKIA_PCSUITE_ACM_INFO(0x04D8), }, /* Nokia 5500 Sport */
1480 	{ NOKIA_PCSUITE_ACM_INFO(0x04C9), }, /* Nokia E50 */
1481 	{ NOKIA_PCSUITE_ACM_INFO(0x0419), }, /* Nokia E60 */
1482 	{ NOKIA_PCSUITE_ACM_INFO(0x044D), }, /* Nokia E61 */
1483 	{ NOKIA_PCSUITE_ACM_INFO(0x0001), }, /* Nokia E61i */
1484 	{ NOKIA_PCSUITE_ACM_INFO(0x0475), }, /* Nokia E62 */
1485 	{ NOKIA_PCSUITE_ACM_INFO(0x0508), }, /* Nokia E65 */
1486 	{ NOKIA_PCSUITE_ACM_INFO(0x0418), }, /* Nokia E70 */
1487 	{ NOKIA_PCSUITE_ACM_INFO(0x0425), }, /* Nokia N71 */
1488 	{ NOKIA_PCSUITE_ACM_INFO(0x0486), }, /* Nokia N73 */
1489 	{ NOKIA_PCSUITE_ACM_INFO(0x04DF), }, /* Nokia N75 */
1490 	{ NOKIA_PCSUITE_ACM_INFO(0x000e), }, /* Nokia N77 */
1491 	{ NOKIA_PCSUITE_ACM_INFO(0x0445), }, /* Nokia N80 */
1492 	{ NOKIA_PCSUITE_ACM_INFO(0x042F), }, /* Nokia N91 & N91 8GB */
1493 	{ NOKIA_PCSUITE_ACM_INFO(0x048E), }, /* Nokia N92 */
1494 	{ NOKIA_PCSUITE_ACM_INFO(0x0420), }, /* Nokia N93 */
1495 	{ NOKIA_PCSUITE_ACM_INFO(0x04E6), }, /* Nokia N93i  */
1496 	{ NOKIA_PCSUITE_ACM_INFO(0x04B2), }, /* Nokia 5700 XpressMusic */
1497 	{ NOKIA_PCSUITE_ACM_INFO(0x0134), }, /* Nokia 6110 Navigator (China) */
1498 	{ NOKIA_PCSUITE_ACM_INFO(0x046E), }, /* Nokia 6110 Navigator */
1499 	{ NOKIA_PCSUITE_ACM_INFO(0x002f), }, /* Nokia 6120 classic &  */
1500 	{ NOKIA_PCSUITE_ACM_INFO(0x0088), }, /* Nokia 6121 classic */
1501 	{ NOKIA_PCSUITE_ACM_INFO(0x00fc), }, /* Nokia 6124 classic */
1502 	{ NOKIA_PCSUITE_ACM_INFO(0x0042), }, /* Nokia E51 */
1503 	{ NOKIA_PCSUITE_ACM_INFO(0x00b0), }, /* Nokia E66 */
1504 	{ NOKIA_PCSUITE_ACM_INFO(0x00ab), }, /* Nokia E71 */
1505 	{ NOKIA_PCSUITE_ACM_INFO(0x0481), }, /* Nokia N76 */
1506 	{ NOKIA_PCSUITE_ACM_INFO(0x0007), }, /* Nokia N81 & N81 8GB */
1507 	{ NOKIA_PCSUITE_ACM_INFO(0x0071), }, /* Nokia N82 */
1508 	{ NOKIA_PCSUITE_ACM_INFO(0x04F0), }, /* Nokia N95 & N95-3 NAM */
1509 	{ NOKIA_PCSUITE_ACM_INFO(0x0070), }, /* Nokia N95 8GB  */
1510 	{ NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1511 	{ NOKIA_PCSUITE_ACM_INFO(0x0099), }, /* Nokia 6210 Navigator, RM-367 */
1512 	{ NOKIA_PCSUITE_ACM_INFO(0x0128), }, /* Nokia 6210 Navigator, RM-419 */
1513 	{ NOKIA_PCSUITE_ACM_INFO(0x008f), }, /* Nokia 6220 Classic */
1514 	{ NOKIA_PCSUITE_ACM_INFO(0x00a0), }, /* Nokia 6650 */
1515 	{ NOKIA_PCSUITE_ACM_INFO(0x007b), }, /* Nokia N78 */
1516 	{ NOKIA_PCSUITE_ACM_INFO(0x0094), }, /* Nokia N85 */
1517 	{ NOKIA_PCSUITE_ACM_INFO(0x003a), }, /* Nokia N96 & N96-3  */
1518 	{ NOKIA_PCSUITE_ACM_INFO(0x00e9), }, /* Nokia 5320 XpressMusic */
1519 	{ NOKIA_PCSUITE_ACM_INFO(0x0108), }, /* Nokia 5320 XpressMusic 2G */
1520 	{ NOKIA_PCSUITE_ACM_INFO(0x01f5), }, /* Nokia N97, RM-505 */
1521 	{ NOKIA_PCSUITE_ACM_INFO(0x02e3), }, /* Nokia 5230, RM-588 */
1522 	{ NOKIA_PCSUITE_ACM_INFO(0x0178), }, /* Nokia E63 */
1523 	{ NOKIA_PCSUITE_ACM_INFO(0x010e), }, /* Nokia E75 */
1524 	{ NOKIA_PCSUITE_ACM_INFO(0x02d9), }, /* Nokia 6760 Slide */
1525 	{ NOKIA_PCSUITE_ACM_INFO(0x01d0), }, /* Nokia E52 */
1526 	{ NOKIA_PCSUITE_ACM_INFO(0x0223), }, /* Nokia E72 */
1527 	{ NOKIA_PCSUITE_ACM_INFO(0x0275), }, /* Nokia X6 */
1528 	{ NOKIA_PCSUITE_ACM_INFO(0x026c), }, /* Nokia N97 Mini */
1529 	{ NOKIA_PCSUITE_ACM_INFO(0x0154), }, /* Nokia 5800 XpressMusic */
1530 	{ NOKIA_PCSUITE_ACM_INFO(0x04ce), }, /* Nokia E90 */
1531 	{ NOKIA_PCSUITE_ACM_INFO(0x01d4), }, /* Nokia E55 */
1532 	{ NOKIA_PCSUITE_ACM_INFO(0x0302), }, /* Nokia N8 */
1533 	{ NOKIA_PCSUITE_ACM_INFO(0x0335), }, /* Nokia E7 */
1534 	{ NOKIA_PCSUITE_ACM_INFO(0x03cd), }, /* Nokia C7 */
1535 	{ SAMSUNG_PCSUITE_ACM_INFO(0x6651), }, /* Samsung GTi8510 (INNOV8) */
1536 
1537 	/* NOTE: non-Nokia COMM/ACM/0xff is likely MSFT RNDIS... NOT a modem! */
1538 
1539 	/* Support Lego NXT using pbLua firmware */
1540 	{ USB_DEVICE(0x0694, 0xff00),
1541 	.driver_info = NOT_A_MODEM,
1542 	},
1543 
1544 	/* Support for Droids MuIn LCD */
1545 	{ USB_DEVICE(0x04d8, 0x000b),
1546 	.driver_info = NO_DATA_INTERFACE,
1547 	},
1548 
1549 	/* control interfaces without any protocol set */
1550 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1551 		USB_CDC_PROTO_NONE) },
1552 
1553 	/* control interfaces with various AT-command sets */
1554 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1555 		USB_CDC_ACM_PROTO_AT_V25TER) },
1556 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1557 		USB_CDC_ACM_PROTO_AT_PCCA101) },
1558 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1559 		USB_CDC_ACM_PROTO_AT_PCCA101_WAKE) },
1560 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1561 		USB_CDC_ACM_PROTO_AT_GSM) },
1562 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1563 		USB_CDC_ACM_PROTO_AT_3G) },
1564 	{ USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM,
1565 		USB_CDC_ACM_PROTO_AT_CDMA) },
1566 
1567 	{ }
1568 };
1569 
1570 MODULE_DEVICE_TABLE(usb, acm_ids);
1571 
1572 static struct usb_driver acm_driver = {
1573 	.name =		"cdc_acm",
1574 	.probe =	acm_probe,
1575 	.disconnect =	acm_disconnect,
1576 #ifdef CONFIG_PM
1577 	.suspend =	acm_suspend,
1578 	.resume =	acm_resume,
1579 	.reset_resume =	acm_reset_resume,
1580 #endif
1581 	.id_table =	acm_ids,
1582 #ifdef CONFIG_PM
1583 	.supports_autosuspend = 1,
1584 #endif
1585 };
1586 
1587 /*
1588  * TTY driver structures.
1589  */
1590 
1591 static const struct tty_operations acm_ops = {
1592 	.open =			acm_tty_open,
1593 	.close =		acm_tty_close,
1594 	.hangup =		acm_tty_hangup,
1595 	.write =		acm_tty_write,
1596 	.write_room =		acm_tty_write_room,
1597 	.ioctl =		acm_tty_ioctl,
1598 	.throttle =		acm_tty_throttle,
1599 	.unthrottle =		acm_tty_unthrottle,
1600 	.chars_in_buffer =	acm_tty_chars_in_buffer,
1601 	.break_ctl =		acm_tty_break_ctl,
1602 	.set_termios =		acm_tty_set_termios,
1603 	.tiocmget =		acm_tty_tiocmget,
1604 	.tiocmset =		acm_tty_tiocmset,
1605 };
1606 
1607 /*
1608  * Init / exit.
1609  */
1610 
1611 static int __init acm_init(void)
1612 {
1613 	int retval;
1614 	acm_tty_driver = alloc_tty_driver(ACM_TTY_MINORS);
1615 	if (!acm_tty_driver)
1616 		return -ENOMEM;
1617 	acm_tty_driver->owner = THIS_MODULE,
1618 	acm_tty_driver->driver_name = "acm",
1619 	acm_tty_driver->name = "ttyACM",
1620 	acm_tty_driver->major = ACM_TTY_MAJOR,
1621 	acm_tty_driver->minor_start = 0,
1622 	acm_tty_driver->type = TTY_DRIVER_TYPE_SERIAL,
1623 	acm_tty_driver->subtype = SERIAL_TYPE_NORMAL,
1624 	acm_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1625 	acm_tty_driver->init_termios = tty_std_termios;
1626 	acm_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD |
1627 								HUPCL | CLOCAL;
1628 	tty_set_operations(acm_tty_driver, &acm_ops);
1629 
1630 	retval = tty_register_driver(acm_tty_driver);
1631 	if (retval) {
1632 		put_tty_driver(acm_tty_driver);
1633 		return retval;
1634 	}
1635 
1636 	retval = usb_register(&acm_driver);
1637 	if (retval) {
1638 		tty_unregister_driver(acm_tty_driver);
1639 		put_tty_driver(acm_tty_driver);
1640 		return retval;
1641 	}
1642 
1643 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
1644 
1645 	return 0;
1646 }
1647 
1648 static void __exit acm_exit(void)
1649 {
1650 	usb_deregister(&acm_driver);
1651 	tty_unregister_driver(acm_tty_driver);
1652 	put_tty_driver(acm_tty_driver);
1653 }
1654 
1655 module_init(acm_init);
1656 module_exit(acm_exit);
1657 
1658 MODULE_AUTHOR(DRIVER_AUTHOR);
1659 MODULE_DESCRIPTION(DRIVER_DESC);
1660 MODULE_LICENSE("GPL");
1661 MODULE_ALIAS_CHARDEV_MAJOR(ACM_TTY_MAJOR);
1662