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Merge remote-tracking branch 'driver-core/driver-core-next'
[linux-2.6/next.git] / drivers / usb / serial / usb-serial.c
blob1c031309ab255ba83b70739566fb8e6c6b1bb58e
1 /*
2 * USB Serial Converter driver
3 *
4 * Copyright (C) 1999 - 2005 Greg Kroah-Hartman (greg@kroah.com)
5 * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
6 * Copyright (C) 2000 Al Borchers (borchers@steinerpoint.com)
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License version
10 * 2 as published by the Free Software Foundation.
11 *
12 * This driver was originally based on the ACM driver by Armin Fuerst (which was
13 * based on a driver by Brad Keryan)
14 *
15 * See Documentation/usb/usb-serial.txt for more information on using this
16 * driver
17 *
18 */
19
20 #include <linux/kernel.h>
21 #include <linux/errno.h>
22 #include <linux/init.h>
23 #include <linux/slab.h>
24 #include <linux/tty.h>
25 #include <linux/tty_driver.h>
26 #include <linux/tty_flip.h>
27 #include <linux/module.h>
28 #include <linux/moduleparam.h>
29 #include <linux/seq_file.h>
30 #include <linux/spinlock.h>
31 #include <linux/mutex.h>
32 #include <linux/list.h>
33 #include <linux/uaccess.h>
34 #include <linux/serial.h>
35 #include <linux/usb.h>
36 #include <linux/usb/serial.h>
37 #include <linux/kfifo.h>
38 #include "pl2303.h"
39
40 /*
41 * Version Information
42 */
43 #define DRIVER_AUTHOR "Greg Kroah-Hartman, greg@kroah.com, http://www.kroah.com/linux/"
44 #define DRIVER_DESC "USB Serial Driver core"
45
46 /* Driver structure we register with the USB core */
47 static struct usb_driver usb_serial_driver = {
48 .name = "usbserial",
49 .probe = usb_serial_probe,
50 .disconnect = usb_serial_disconnect,
51 .suspend = usb_serial_suspend,
52 .resume = usb_serial_resume,
53 .no_dynamic_id = 1,
54 .supports_autosuspend = 1,
55 };
56
57 /* There is no MODULE_DEVICE_TABLE for usbserial.c. Instead
58 the MODULE_DEVICE_TABLE declarations in each serial driver
59 cause the "hotplug" program to pull in whatever module is necessary
60 via modprobe, and modprobe will load usbserial because the serial
61 drivers depend on it.
62 */
63
64 static int debug;
65 /* initially all NULL */
66 static struct usb_serial *serial_table[SERIAL_TTY_MINORS];
67 static DEFINE_MUTEX(table_lock);
68 static LIST_HEAD(usb_serial_driver_list);
69
70 /*
71 * Look up the serial structure. If it is found and it hasn't been
72 * disconnected, return with its disc_mutex held and its refcount
73 * incremented. Otherwise return NULL.
74 */
75 struct usb_serial *usb_serial_get_by_index(unsigned index)
76 {
77 struct usb_serial *serial;
78
79 mutex_lock(&table_lock);
80 serial = serial_table[index];
81
82 if (serial) {
83 mutex_lock(&serial->disc_mutex);
84 if (serial->disconnected) {
85 mutex_unlock(&serial->disc_mutex);
86 serial = NULL;
87 } else {
88 kref_get(&serial->kref);
89 }
90 }
91 mutex_unlock(&table_lock);
92 return serial;
93 }
94
95 static struct usb_serial *get_free_serial(struct usb_serial *serial,
96 int num_ports, unsigned int *minor)
97 {
98 unsigned int i, j;
99 int good_spot;
100
101 dbg("%s %d", __func__, num_ports);
102
103 *minor = 0;
104 mutex_lock(&table_lock);
105 for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
106 if (serial_table[i])
107 continue;
108
109 good_spot = 1;
110 for (j = 1; j <= num_ports-1; ++j)
111 if ((i+j >= SERIAL_TTY_MINORS) || (serial_table[i+j])) {
112 good_spot = 0;
113 i += j;
114 break;
115 }
116 if (good_spot == 0)
117 continue;
118
119 *minor = i;
120 j = 0;
121 dbg("%s - minor base = %d", __func__, *minor);
122 for (i = *minor; (i < (*minor + num_ports)) && (i < SERIAL_TTY_MINORS); ++i) {
123 serial_table[i] = serial;
124 serial->port[j++]->number = i;
125 }
126 mutex_unlock(&table_lock);
127 return serial;
128 }
129 mutex_unlock(&table_lock);
130 return NULL;
131 }
132
133 static void return_serial(struct usb_serial *serial)
134 {
135 int i;
136
137 dbg("%s", __func__);
138
139 mutex_lock(&table_lock);
140 for (i = 0; i < serial->num_ports; ++i)
141 serial_table[serial->minor + i] = NULL;
142 mutex_unlock(&table_lock);
143 }
144
145 static void destroy_serial(struct kref *kref)
146 {
147 struct usb_serial *serial;
148 struct usb_serial_port *port;
149 int i;
150
151 serial = to_usb_serial(kref);
152
153 dbg("%s - %s", __func__, serial->type->description);
154
155 /* return the minor range that this device had */
156 if (serial->minor != SERIAL_TTY_NO_MINOR)
157 return_serial(serial);
158
159 if (serial->attached)
160 serial->type->release(serial);
161
162 /* Now that nothing is using the ports, they can be freed */
163 for (i = 0; i < serial->num_port_pointers; ++i) {
164 port = serial->port[i];
165 if (port) {
166 port->serial = NULL;
167 put_device(&port->dev);
168 }
169 }
170
171 usb_put_dev(serial->dev);
172 kfree(serial);
173 }
174
175 void usb_serial_put(struct usb_serial *serial)
176 {
177 kref_put(&serial->kref, destroy_serial);
178 }
179
180 /*****************************************************************************
181 * Driver tty interface functions
182 *****************************************************************************/
183
184 /**
185 * serial_install - install tty
186 * @driver: the driver (USB in our case)
187 * @tty: the tty being created
188 *
189 * Create the termios objects for this tty. We use the default
190 * USB serial settings but permit them to be overridden by
191 * serial->type->init_termios.
192 *
193 * This is the first place a new tty gets used. Hence this is where we
194 * acquire references to the usb_serial structure and the driver module,
195 * where we store a pointer to the port, and where we do an autoresume.
196 * All these actions are reversed in serial_cleanup().
197 */
198 static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
199 {
200 int idx = tty->index;
201 struct usb_serial *serial;
202 struct usb_serial_port *port;
203 int retval = -ENODEV;
204
205 dbg("%s", __func__);
206
207 serial = usb_serial_get_by_index(idx);
208 if (!serial)
209 return retval;
210
211 port = serial->port[idx - serial->minor];
212 if (!port)
213 goto error_no_port;
214 if (!try_module_get(serial->type->driver.owner))
215 goto error_module_get;
216
217 /* perform the standard setup */
218 retval = tty_init_termios(tty);
219 if (retval)
220 goto error_init_termios;
221
222 retval = usb_autopm_get_interface(serial->interface);
223 if (retval)
224 goto error_get_interface;
225
226 mutex_unlock(&serial->disc_mutex);
227
228 /* allow the driver to update the settings */
229 if (serial->type->init_termios)
230 serial->type->init_termios(tty);
231
232 tty->driver_data = port;
233
234 /* Final install (we use the default method) */
235 tty_driver_kref_get(driver);
236 tty->count++;
237 driver->ttys[idx] = tty;
238 return retval;
239
240 error_get_interface:
241 error_init_termios:
242 module_put(serial->type->driver.owner);
243 error_module_get:
244 error_no_port:
245 usb_serial_put(serial);
246 mutex_unlock(&serial->disc_mutex);
247 return retval;
248 }
249
250 static int serial_activate(struct tty_port *tport, struct tty_struct *tty)
251 {
252 struct usb_serial_port *port =
253 container_of(tport, struct usb_serial_port, port);
254 struct usb_serial *serial = port->serial;
255 int retval;
256
257 mutex_lock(&serial->disc_mutex);
258 if (serial->disconnected)
259 retval = -ENODEV;
260 else
261 retval = port->serial->type->open(tty, port);
262 mutex_unlock(&serial->disc_mutex);
263 return retval;
264 }
265
266 static int serial_open(struct tty_struct *tty, struct file *filp)
267 {
268 struct usb_serial_port *port = tty->driver_data;
269
270 dbg("%s - port %d", __func__, port->number);
271 return tty_port_open(&port->port, tty, filp);
272 }
273
274 /**
275 * serial_down - shut down hardware
276 * @tport: tty port to shut down
277 *
278 * Shut down a USB serial port unless it is the console. We never
279 * shut down the console hardware as it will always be in use. Serialized
280 * against activate by the tport mutex and kept to matching open/close pairs
281 * of calls by the ASYNCB_INITIALIZED flag.
282 */
283 static void serial_down(struct tty_port *tport)
284 {
285 struct usb_serial_port *port =
286 container_of(tport, struct usb_serial_port, port);
287 struct usb_serial_driver *drv = port->serial->type;
288 /*
289 * The console is magical. Do not hang up the console hardware
290 * or there will be tears.
291 */
292 if (port->port.console)
293 return;
294 if (drv->close)
295 drv->close(port);
296 }
297
298 static void serial_hangup(struct tty_struct *tty)
299 {
300 struct usb_serial_port *port = tty->driver_data;
301 dbg("%s - port %d", __func__, port->number);
302 tty_port_hangup(&port->port);
303 }
304
305 static void serial_close(struct tty_struct *tty, struct file *filp)
306 {
307 struct usb_serial_port *port = tty->driver_data;
308 dbg("%s - port %d", __func__, port->number);
309 tty_port_close(&port->port, tty, filp);
310 }
311
312 /**
313 * serial_cleanup - free resources post close/hangup
314 * @port: port to free up
315 *
316 * Do the resource freeing and refcount dropping for the port.
317 * Avoid freeing the console.
318 *
319 * Called asynchronously after the last tty kref is dropped,
320 * and the tty layer has already done the tty_shutdown(tty);
321 */
322 static void serial_cleanup(struct tty_struct *tty)
323 {
324 struct usb_serial_port *port = tty->driver_data;
325 struct usb_serial *serial;
326 struct module *owner;
327
328 /* The console is magical. Do not hang up the console hardware
329 * or there will be tears.
330 */
331 if (port->port.console)
332 return;
333
334 dbg("%s - port %d", __func__, port->number);
335
336 tty->driver_data = NULL;
337
338 serial = port->serial;
339 owner = serial->type->driver.owner;
340
341 mutex_lock(&serial->disc_mutex);
342 if (!serial->disconnected)
343 usb_autopm_put_interface(serial->interface);
344 mutex_unlock(&serial->disc_mutex);
345
346 usb_serial_put(serial);
347 module_put(owner);
348 }
349
350 static int serial_write(struct tty_struct *tty, const unsigned char *buf,
351 int count)
352 {
353 struct usb_serial_port *port = tty->driver_data;
354 int retval = -ENODEV;
355
356 if (port->serial->dev->state == USB_STATE_NOTATTACHED)
357 goto exit;
358
359 dbg("%s - port %d, %d byte(s)", __func__, port->number, count);
360
361 /* pass on to the driver specific version of this function */
362 retval = port->serial->type->write(tty, port, buf, count);
363
364 exit:
365 return retval;
366 }
367
368 static int serial_write_room(struct tty_struct *tty)
369 {
370 struct usb_serial_port *port = tty->driver_data;
371 dbg("%s - port %d", __func__, port->number);
372 /* pass on to the driver specific version of this function */
373 return port->serial->type->write_room(tty);
374 }
375
376 static int serial_chars_in_buffer(struct tty_struct *tty)
377 {
378 struct usb_serial_port *port = tty->driver_data;
379 dbg("%s - port %d", __func__, port->number);
380
381 /* if the device was unplugged then any remaining characters
382 fell out of the connector ;) */
383 if (port->serial->disconnected)
384 return 0;
385 /* pass on to the driver specific version of this function */
386 return port->serial->type->chars_in_buffer(tty);
387 }
388
389 static void serial_throttle(struct tty_struct *tty)
390 {
391 struct usb_serial_port *port = tty->driver_data;
392 dbg("%s - port %d", __func__, port->number);
393
394 /* pass on to the driver specific version of this function */
395 if (port->serial->type->throttle)
396 port->serial->type->throttle(tty);
397 }
398
399 static void serial_unthrottle(struct tty_struct *tty)
400 {
401 struct usb_serial_port *port = tty->driver_data;
402 dbg("%s - port %d", __func__, port->number);
403
404 /* pass on to the driver specific version of this function */
405 if (port->serial->type->unthrottle)
406 port->serial->type->unthrottle(tty);
407 }
408
409 static int serial_ioctl(struct tty_struct *tty,
410 unsigned int cmd, unsigned long arg)
411 {
412 struct usb_serial_port *port = tty->driver_data;
413 int retval = -ENODEV;
414
415 dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
416
417 /* pass on to the driver specific version of this function
418 if it is available */
419 if (port->serial->type->ioctl) {
420 retval = port->serial->type->ioctl(tty, cmd, arg);
421 } else
422 retval = -ENOIOCTLCMD;
423 return retval;
424 }
425
426 static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
427 {
428 struct usb_serial_port *port = tty->driver_data;
429 dbg("%s - port %d", __func__, port->number);
430
431 /* pass on to the driver specific version of this function
432 if it is available */
433 if (port->serial->type->set_termios)
434 port->serial->type->set_termios(tty, port, old);
435 else
436 tty_termios_copy_hw(tty->termios, old);
437 }
438
439 static int serial_break(struct tty_struct *tty, int break_state)
440 {
441 struct usb_serial_port *port = tty->driver_data;
442
443 dbg("%s - port %d", __func__, port->number);
444
445 /* pass on to the driver specific version of this function
446 if it is available */
447 if (port->serial->type->break_ctl)
448 port->serial->type->break_ctl(tty, break_state);
449 return 0;
450 }
451
452 static int serial_proc_show(struct seq_file *m, void *v)
453 {
454 struct usb_serial *serial;
455 int i;
456 char tmp[40];
457
458 dbg("%s", __func__);
459 seq_puts(m, "usbserinfo:1.0 driver:2.0\n");
460 for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
461 serial = usb_serial_get_by_index(i);
462 if (serial == NULL)
463 continue;
464
465 seq_printf(m, "%d:", i);
466 if (serial->type->driver.owner)
467 seq_printf(m, " module:%s",
468 module_name(serial->type->driver.owner));
469 seq_printf(m, " name:\"%s\"",
470 serial->type->description);
471 seq_printf(m, " vendor:%04x product:%04x",
472 le16_to_cpu(serial->dev->descriptor.idVendor),
473 le16_to_cpu(serial->dev->descriptor.idProduct));
474 seq_printf(m, " num_ports:%d", serial->num_ports);
475 seq_printf(m, " port:%d", i - serial->minor + 1);
476 usb_make_path(serial->dev, tmp, sizeof(tmp));
477 seq_printf(m, " path:%s", tmp);
478
479 seq_putc(m, '\n');
480 usb_serial_put(serial);
481 mutex_unlock(&serial->disc_mutex);
482 }
483 return 0;
484 }
485
486 static int serial_proc_open(struct inode *inode, struct file *file)
487 {
488 return single_open(file, serial_proc_show, NULL);
489 }
490
491 static const struct file_operations serial_proc_fops = {
492 .owner = THIS_MODULE,
493 .open = serial_proc_open,
494 .read = seq_read,
495 .llseek = seq_lseek,
496 .release = single_release,
497 };
498
499 static int serial_tiocmget(struct tty_struct *tty)
500 {
501 struct usb_serial_port *port = tty->driver_data;
502
503 dbg("%s - port %d", __func__, port->number);
504
505 if (port->serial->type->tiocmget)
506 return port->serial->type->tiocmget(tty);
507 return -EINVAL;
508 }
509
510 static int serial_tiocmset(struct tty_struct *tty,
511 unsigned int set, unsigned int clear)
512 {
513 struct usb_serial_port *port = tty->driver_data;
514
515 dbg("%s - port %d", __func__, port->number);
516
517 if (port->serial->type->tiocmset)
518 return port->serial->type->tiocmset(tty, set, clear);
519 return -EINVAL;
520 }
521
522 static int serial_get_icount(struct tty_struct *tty,
523 struct serial_icounter_struct *icount)
524 {
525 struct usb_serial_port *port = tty->driver_data;
526
527 dbg("%s - port %d", __func__, port->number);
528
529 if (port->serial->type->get_icount)
530 return port->serial->type->get_icount(tty, icount);
531 return -EINVAL;
532 }
533
534 /*
535 * We would be calling tty_wakeup here, but unfortunately some line
536 * disciplines have an annoying habit of calling tty->write from
537 * the write wakeup callback (e.g. n_hdlc.c).
538 */
539 void usb_serial_port_softint(struct usb_serial_port *port)
540 {
541 schedule_work(&port->work);
542 }
543 EXPORT_SYMBOL_GPL(usb_serial_port_softint);
544
545 static void usb_serial_port_work(struct work_struct *work)
546 {
547 struct usb_serial_port *port =
548 container_of(work, struct usb_serial_port, work);
549 struct tty_struct *tty;
550
551 dbg("%s - port %d", __func__, port->number);
552
553 tty = tty_port_tty_get(&port->port);
554 if (!tty)
555 return;
556
557 tty_wakeup(tty);
558 tty_kref_put(tty);
559 }
560
561 static void kill_traffic(struct usb_serial_port *port)
562 {
563 int i;
564
565 usb_kill_urb(port->read_urb);
566 usb_kill_urb(port->write_urb);
567 for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
568 usb_kill_urb(port->write_urbs[i]);
569 /*
570 * This is tricky.
571 * Some drivers submit the read_urb in the
572 * handler for the write_urb or vice versa
573 * this order determines the order in which
574 * usb_kill_urb() must be used to reliably
575 * kill the URBs. As it is unknown here,
576 * both orders must be used in turn.
577 * The call below is not redundant.
578 */
579 usb_kill_urb(port->read_urb);
580 usb_kill_urb(port->interrupt_in_urb);
581 usb_kill_urb(port->interrupt_out_urb);
582 }
583
584 static void port_release(struct device *dev)
585 {
586 struct usb_serial_port *port = to_usb_serial_port(dev);
587 int i;
588
589 dbg ("%s - %s", __func__, dev_name(dev));
590
591 /*
592 * Stop all the traffic before cancelling the work, so that
593 * nobody will restart it by calling usb_serial_port_softint.
594 */
595 kill_traffic(port);
596 cancel_work_sync(&port->work);
597
598 usb_free_urb(port->read_urb);
599 usb_free_urb(port->write_urb);
600 usb_free_urb(port->interrupt_in_urb);
601 usb_free_urb(port->interrupt_out_urb);
602 for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
603 usb_free_urb(port->write_urbs[i]);
604 kfree(port->bulk_out_buffers[i]);
605 }
606 kfifo_free(&port->write_fifo);
607 kfree(port->bulk_in_buffer);
608 kfree(port->bulk_out_buffer);
609 kfree(port->interrupt_in_buffer);
610 kfree(port->interrupt_out_buffer);
611 kfree(port);
612 }
613
614 static struct usb_serial *create_serial(struct usb_device *dev,
615 struct usb_interface *interface,
616 struct usb_serial_driver *driver)
617 {
618 struct usb_serial *serial;
619
620 serial = kzalloc(sizeof(*serial), GFP_KERNEL);
621 if (!serial) {
622 dev_err(&dev->dev, "%s - out of memory\n", __func__);
623 return NULL;
624 }
625 serial->dev = usb_get_dev(dev);
626 serial->type = driver;
627 serial->interface = interface;
628 kref_init(&serial->kref);
629 mutex_init(&serial->disc_mutex);
630 serial->minor = SERIAL_TTY_NO_MINOR;
631
632 return serial;
633 }
634
635 static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
636 struct usb_serial_driver *drv)
637 {
638 struct usb_dynid *dynid;
639
640 spin_lock(&drv->dynids.lock);
641 list_for_each_entry(dynid, &drv->dynids.list, node) {
642 if (usb_match_one_id(intf, &dynid->id)) {
643 spin_unlock(&drv->dynids.lock);
644 return &dynid->id;
645 }
646 }
647 spin_unlock(&drv->dynids.lock);
648 return NULL;
649 }
650
651 static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
652 struct usb_interface *intf)
653 {
654 const struct usb_device_id *id;
655
656 id = usb_match_id(intf, drv->id_table);
657 if (id) {
658 dbg("static descriptor matches");
659 goto exit;
660 }
661 id = match_dynamic_id(intf, drv);
662 if (id)
663 dbg("dynamic descriptor matches");
664 exit:
665 return id;
666 }
667
668 /* Caller must hold table_lock */
669 static struct usb_serial_driver *search_serial_device(
670 struct usb_interface *iface)
671 {
672 const struct usb_device_id *id;
673 struct usb_serial_driver *drv;
674
675 /* Check if the usb id matches a known device */
676 list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
677 id = get_iface_id(drv, iface);
678 if (id)
679 return drv;
680 }
681
682 return NULL;
683 }
684
685 static int serial_carrier_raised(struct tty_port *port)
686 {
687 struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
688 struct usb_serial_driver *drv = p->serial->type;
689 if (drv->carrier_raised)
690 return drv->carrier_raised(p);
691 /* No carrier control - don't block */
692 return 1;
693 }
694
695 static void serial_dtr_rts(struct tty_port *port, int on)
696 {
697 struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
698 struct usb_serial_driver *drv = p->serial->type;
699 if (drv->dtr_rts)
700 drv->dtr_rts(p, on);
701 }
702
703 static const struct tty_port_operations serial_port_ops = {
704 .carrier_raised = serial_carrier_raised,
705 .dtr_rts = serial_dtr_rts,
706 .activate = serial_activate,
707 .shutdown = serial_down,
708 };
709
710 int usb_serial_probe(struct usb_interface *interface,
711 const struct usb_device_id *id)
712 {
713 struct usb_device *dev = interface_to_usbdev(interface);
714 struct usb_serial *serial = NULL;
715 struct usb_serial_port *port;
716 struct usb_host_interface *iface_desc;
717 struct usb_endpoint_descriptor *endpoint;
718 struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
719 struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
720 struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
721 struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
722 struct usb_serial_driver *type = NULL;
723 int retval;
724 unsigned int minor;
725 int buffer_size;
726 int i;
727 int num_interrupt_in = 0;
728 int num_interrupt_out = 0;
729 int num_bulk_in = 0;
730 int num_bulk_out = 0;
731 int num_ports = 0;
732 int max_endpoints;
733
734 mutex_lock(&table_lock);
735 type = search_serial_device(interface);
736 if (!type) {
737 mutex_unlock(&table_lock);
738 dbg("none matched");
739 return -ENODEV;
740 }
741
742 if (!try_module_get(type->driver.owner)) {
743 mutex_unlock(&table_lock);
744 dev_err(&interface->dev, "module get failed, exiting\n");
745 return -EIO;
746 }
747 mutex_unlock(&table_lock);
748
749 serial = create_serial(dev, interface, type);
750 if (!serial) {
751 module_put(type->driver.owner);
752 dev_err(&interface->dev, "%s - out of memory\n", __func__);
753 return -ENOMEM;
754 }
755
756 /* if this device type has a probe function, call it */
757 if (type->probe) {
758 const struct usb_device_id *id;
759
760 id = get_iface_id(type, interface);
761 retval = type->probe(serial, id);
762
763 if (retval) {
764 dbg("sub driver rejected device");
765 kfree(serial);
766 module_put(type->driver.owner);
767 return retval;
768 }
769 }
770
771 /* descriptor matches, let's find the endpoints needed */
772 /* check out the endpoints */
773 iface_desc = interface->cur_altsetting;
774 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
775 endpoint = &iface_desc->endpoint[i].desc;
776
777 if (usb_endpoint_is_bulk_in(endpoint)) {
778 /* we found a bulk in endpoint */
779 dbg("found bulk in on endpoint %d", i);
780 bulk_in_endpoint[num_bulk_in] = endpoint;
781 ++num_bulk_in;
782 }
783
784 if (usb_endpoint_is_bulk_out(endpoint)) {
785 /* we found a bulk out endpoint */
786 dbg("found bulk out on endpoint %d", i);
787 bulk_out_endpoint[num_bulk_out] = endpoint;
788 ++num_bulk_out;
789 }
790
791 if (usb_endpoint_is_int_in(endpoint)) {
792 /* we found a interrupt in endpoint */
793 dbg("found interrupt in on endpoint %d", i);
794 interrupt_in_endpoint[num_interrupt_in] = endpoint;
795 ++num_interrupt_in;
796 }
797
798 if (usb_endpoint_is_int_out(endpoint)) {
799 /* we found an interrupt out endpoint */
800 dbg("found interrupt out on endpoint %d", i);
801 interrupt_out_endpoint[num_interrupt_out] = endpoint;
802 ++num_interrupt_out;
803 }
804 }
805
806 #if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
807 /* BEGIN HORRIBLE HACK FOR PL2303 */
808 /* this is needed due to the looney way its endpoints are set up */
809 if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
810 (le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
811 ((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
812 (le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
813 ((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
814 (le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
815 ((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
816 (le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
817 if (interface != dev->actconfig->interface[0]) {
818 /* check out the endpoints of the other interface*/
819 iface_desc = dev->actconfig->interface[0]->cur_altsetting;
820 for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
821 endpoint = &iface_desc->endpoint[i].desc;
822 if (usb_endpoint_is_int_in(endpoint)) {
823 /* we found a interrupt in endpoint */
824 dbg("found interrupt in for Prolific device on separate interface");
825 interrupt_in_endpoint[num_interrupt_in] = endpoint;
826 ++num_interrupt_in;
827 }
828 }
829 }
830
831 /* Now make sure the PL-2303 is configured correctly.
832 * If not, give up now and hope this hack will work
833 * properly during a later invocation of usb_serial_probe
834 */
835 if (num_bulk_in == 0 || num_bulk_out == 0) {
836 dev_info(&interface->dev, "PL-2303 hack: descriptors matched but endpoints did not\n");
837 kfree(serial);
838 module_put(type->driver.owner);
839 return -ENODEV;
840 }
841 }
842 /* END HORRIBLE HACK FOR PL2303 */
843 #endif
844
845 #ifdef CONFIG_USB_SERIAL_GENERIC
846 if (type == &usb_serial_generic_device) {
847 num_ports = num_bulk_out;
848 if (num_ports == 0) {
849 dev_err(&interface->dev,
850 "Generic device with no bulk out, not allowed.\n");
851 kfree(serial);
852 module_put(type->driver.owner);
853 return -EIO;
854 }
855 }
856 #endif
857 if (!num_ports) {
858 /* if this device type has a calc_num_ports function, call it */
859 if (type->calc_num_ports)
860 num_ports = type->calc_num_ports(serial);
861 if (!num_ports)
862 num_ports = type->num_ports;
863 }
864
865 serial->num_ports = num_ports;
866 serial->num_bulk_in = num_bulk_in;
867 serial->num_bulk_out = num_bulk_out;
868 serial->num_interrupt_in = num_interrupt_in;
869 serial->num_interrupt_out = num_interrupt_out;
870
871 /* found all that we need */
872 dev_info(&interface->dev, "%s converter detected\n",
873 type->description);
874
875 /* create our ports, we need as many as the max endpoints */
876 /* we don't use num_ports here because some devices have more
877 endpoint pairs than ports */
878 max_endpoints = max(num_bulk_in, num_bulk_out);
879 max_endpoints = max(max_endpoints, num_interrupt_in);
880 max_endpoints = max(max_endpoints, num_interrupt_out);
881 max_endpoints = max(max_endpoints, (int)serial->num_ports);
882 serial->num_port_pointers = max_endpoints;
883
884 dbg("%s - setting up %d port structures for this device",
885 __func__, max_endpoints);
886 for (i = 0; i < max_endpoints; ++i) {
887 port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
888 if (!port)
889 goto probe_error;
890 tty_port_init(&port->port);
891 port->port.ops = &serial_port_ops;
892 port->serial = serial;
893 spin_lock_init(&port->lock);
894 /* Keep this for private driver use for the moment but
895 should probably go away */
896 INIT_WORK(&port->work, usb_serial_port_work);
897 serial->port[i] = port;
898 port->dev.parent = &interface->dev;
899 port->dev.driver = NULL;
900 port->dev.bus = &usb_serial_bus_type;
901 port->dev.release = &port_release;
902 device_initialize(&port->dev);
903 }
904
905 /* set up the endpoint information */
906 for (i = 0; i < num_bulk_in; ++i) {
907 endpoint = bulk_in_endpoint[i];
908 port = serial->port[i];
909 port->read_urb = usb_alloc_urb(0, GFP_KERNEL);
910 if (!port->read_urb) {
911 dev_err(&interface->dev, "No free urbs available\n");
912 goto probe_error;
913 }
914 buffer_size = max_t(int, serial->type->bulk_in_size,
915 le16_to_cpu(endpoint->wMaxPacketSize));
916 port->bulk_in_size = buffer_size;
917 port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
918 port->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
919 if (!port->bulk_in_buffer) {
920 dev_err(&interface->dev,
921 "Couldn't allocate bulk_in_buffer\n");
922 goto probe_error;
923 }
924 usb_fill_bulk_urb(port->read_urb, dev,
925 usb_rcvbulkpipe(dev,
926 endpoint->bEndpointAddress),
927 port->bulk_in_buffer, buffer_size,
928 serial->type->read_bulk_callback, port);
929 }
930
931 for (i = 0; i < num_bulk_out; ++i) {
932 int j;
933
934 endpoint = bulk_out_endpoint[i];
935 port = serial->port[i];
936 port->write_urb = usb_alloc_urb(0, GFP_KERNEL);
937 if (!port->write_urb) {
938 dev_err(&interface->dev, "No free urbs available\n");
939 goto probe_error;
940 }
941 if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
942 goto probe_error;
943 buffer_size = serial->type->bulk_out_size;
944 if (!buffer_size)
945 buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
946 port->bulk_out_size = buffer_size;
947 port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
948 port->bulk_out_buffer = kmalloc(buffer_size, GFP_KERNEL);
949 if (!port->bulk_out_buffer) {
950 dev_err(&interface->dev,
951 "Couldn't allocate bulk_out_buffer\n");
952 goto probe_error;
953 }
954 usb_fill_bulk_urb(port->write_urb, dev,
955 usb_sndbulkpipe(dev,
956 endpoint->bEndpointAddress),
957 port->bulk_out_buffer, buffer_size,
958 serial->type->write_bulk_callback, port);
959 for (j = 0; j < ARRAY_SIZE(port->write_urbs); ++j) {
960 set_bit(j, &port->write_urbs_free);
961 port->write_urbs[j] = usb_alloc_urb(0, GFP_KERNEL);
962 if (!port->write_urbs[j]) {
963 dev_err(&interface->dev,
964 "No free urbs available\n");
965 goto probe_error;
966 }
967 port->bulk_out_buffers[j] = kmalloc(buffer_size,
968 GFP_KERNEL);
969 if (!port->bulk_out_buffers[j]) {
970 dev_err(&interface->dev,
971 "Couldn't allocate bulk_out_buffer\n");
972 goto probe_error;
973 }
974 usb_fill_bulk_urb(port->write_urbs[j], dev,
975 usb_sndbulkpipe(dev,
976 endpoint->bEndpointAddress),
977 port->bulk_out_buffers[j], buffer_size,
978 serial->type->write_bulk_callback,
979 port);
980 }
981 }
982
983 if (serial->type->read_int_callback) {
984 for (i = 0; i < num_interrupt_in; ++i) {
985 endpoint = interrupt_in_endpoint[i];
986 port = serial->port[i];
987 port->interrupt_in_urb = usb_alloc_urb(0, GFP_KERNEL);
988 if (!port->interrupt_in_urb) {
989 dev_err(&interface->dev,
990 "No free urbs available\n");
991 goto probe_error;
992 }
993 buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
994 port->interrupt_in_endpointAddress =
995 endpoint->bEndpointAddress;
996 port->interrupt_in_buffer = kmalloc(buffer_size,
997 GFP_KERNEL);
998 if (!port->interrupt_in_buffer) {
999 dev_err(&interface->dev,
1000 "Couldn't allocate interrupt_in_buffer\n");
1001 goto probe_error;
1002 }
1003 usb_fill_int_urb(port->interrupt_in_urb, dev,
1004 usb_rcvintpipe(dev,
1005 endpoint->bEndpointAddress),
1006 port->interrupt_in_buffer, buffer_size,
1007 serial->type->read_int_callback, port,
1008 endpoint->bInterval);
1009 }
1010 } else if (num_interrupt_in) {
1011 dbg("the device claims to support interrupt in transfers, but read_int_callback is not defined");
1012 }
1013
1014 if (serial->type->write_int_callback) {
1015 for (i = 0; i < num_interrupt_out; ++i) {
1016 endpoint = interrupt_out_endpoint[i];
1017 port = serial->port[i];
1018 port->interrupt_out_urb = usb_alloc_urb(0, GFP_KERNEL);
1019 if (!port->interrupt_out_urb) {
1020 dev_err(&interface->dev,
1021 "No free urbs available\n");
1022 goto probe_error;
1023 }
1024 buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
1025 port->interrupt_out_size = buffer_size;
1026 port->interrupt_out_endpointAddress =
1027 endpoint->bEndpointAddress;
1028 port->interrupt_out_buffer = kmalloc(buffer_size,
1029 GFP_KERNEL);
1030 if (!port->interrupt_out_buffer) {
1031 dev_err(&interface->dev,
1032 "Couldn't allocate interrupt_out_buffer\n");
1033 goto probe_error;
1034 }
1035 usb_fill_int_urb(port->interrupt_out_urb, dev,
1036 usb_sndintpipe(dev,
1037 endpoint->bEndpointAddress),
1038 port->interrupt_out_buffer, buffer_size,
1039 serial->type->write_int_callback, port,
1040 endpoint->bInterval);
1041 }
1042 } else if (num_interrupt_out) {
1043 dbg("the device claims to support interrupt out transfers, but write_int_callback is not defined");
1044 }
1045
1046 /* if this device type has an attach function, call it */
1047 if (type->attach) {
1048 retval = type->attach(serial);
1049 if (retval < 0)
1050 goto probe_error;
1051 serial->attached = 1;
1052 if (retval > 0) {
1053 /* quietly accept this device, but don't bind to a
1054 serial port as it's about to disappear */
1055 serial->num_ports = 0;
1056 goto exit;
1057 }
1058 } else {
1059 serial->attached = 1;
1060 }
1061
1062 if (get_free_serial(serial, num_ports, &minor) == NULL) {
1063 dev_err(&interface->dev, "No more free serial devices\n");
1064 goto probe_error;
1065 }
1066 serial->minor = minor;
1067
1068 /* register all of the individual ports with the driver core */
1069 for (i = 0; i < num_ports; ++i) {
1070 port = serial->port[i];
1071 dev_set_name(&port->dev, "ttyUSB%d", port->number);
1072 dbg ("%s - registering %s", __func__, dev_name(&port->dev));
1073 port->dev_state = PORT_REGISTERING;
1074 device_enable_async_suspend(&port->dev);
1075
1076 retval = device_add(&port->dev);
1077 if (retval) {
1078 dev_err(&port->dev, "Error registering port device, "
1079 "continuing\n");
1080 port->dev_state = PORT_UNREGISTERED;
1081 } else {
1082 port->dev_state = PORT_REGISTERED;
1083 }
1084 }
1085
1086 usb_serial_console_init(debug, minor);
1087
1088 exit:
1089 /* success */
1090 usb_set_intfdata(interface, serial);
1091 module_put(type->driver.owner);
1092 return 0;
1093
1094 probe_error:
1095 usb_serial_put(serial);
1096 module_put(type->driver.owner);
1097 return -EIO;
1098 }
1099 EXPORT_SYMBOL_GPL(usb_serial_probe);
1100
1101 void usb_serial_disconnect(struct usb_interface *interface)
1102 {
1103 int i;
1104 struct usb_serial *serial = usb_get_intfdata(interface);
1105 struct device *dev = &interface->dev;
1106 struct usb_serial_port *port;
1107
1108 usb_serial_console_disconnect(serial);
1109 dbg("%s", __func__);
1110
1111 mutex_lock(&serial->disc_mutex);
1112 usb_set_intfdata(interface, NULL);
1113 /* must set a flag, to signal subdrivers */
1114 serial->disconnected = 1;
1115 mutex_unlock(&serial->disc_mutex);
1116
1117 for (i = 0; i < serial->num_ports; ++i) {
1118 port = serial->port[i];
1119 if (port) {
1120 struct tty_struct *tty = tty_port_tty_get(&port->port);
1121 if (tty) {
1122 tty_vhangup(tty);
1123 tty_kref_put(tty);
1124 }
1125 kill_traffic(port);
1126 cancel_work_sync(&port->work);
1127 if (port->dev_state == PORT_REGISTERED) {
1128
1129 /* Make sure the port is bound so that the
1130 * driver's port_remove method is called.
1131 */
1132 if (!port->dev.driver) {
1133 int rc;
1134
1135 port->dev.driver =
1136 &serial->type->driver;
1137 rc = device_bind_driver(&port->dev);
1138 }
1139 port->dev_state = PORT_UNREGISTERING;
1140 device_del(&port->dev);
1141 port->dev_state = PORT_UNREGISTERED;
1142 }
1143 }
1144 }
1145 serial->type->disconnect(serial);
1146
1147 /* let the last holder of this object cause it to be cleaned up */
1148 usb_serial_put(serial);
1149 dev_info(dev, "device disconnected\n");
1150 }
1151 EXPORT_SYMBOL_GPL(usb_serial_disconnect);
1152
1153 int usb_serial_suspend(struct usb_interface *intf, pm_message_t message)
1154 {
1155 struct usb_serial *serial = usb_get_intfdata(intf);
1156 struct usb_serial_port *port;
1157 int i, r = 0;
1158
1159 serial->suspending = 1;
1160
1161 if (serial->type->suspend) {
1162 r = serial->type->suspend(serial, message);
1163 if (r < 0) {
1164 serial->suspending = 0;
1165 goto err_out;
1166 }
1167 }
1168
1169 for (i = 0; i < serial->num_ports; ++i) {
1170 port = serial->port[i];
1171 if (port)
1172 kill_traffic(port);
1173 }
1174
1175 err_out:
1176 return r;
1177 }
1178 EXPORT_SYMBOL(usb_serial_suspend);
1179
1180 int usb_serial_resume(struct usb_interface *intf)
1181 {
1182 struct usb_serial *serial = usb_get_intfdata(intf);
1183 int rv;
1184
1185 serial->suspending = 0;
1186 if (serial->type->resume)
1187 rv = serial->type->resume(serial);
1188 else
1189 rv = usb_serial_generic_resume(serial);
1190
1191 return rv;
1192 }
1193 EXPORT_SYMBOL(usb_serial_resume);
1194
1195 static const struct tty_operations serial_ops = {
1196 .open = serial_open,
1197 .close = serial_close,
1198 .write = serial_write,
1199 .hangup = serial_hangup,
1200 .write_room = serial_write_room,
1201 .ioctl = serial_ioctl,
1202 .set_termios = serial_set_termios,
1203 .throttle = serial_throttle,
1204 .unthrottle = serial_unthrottle,
1205 .break_ctl = serial_break,
1206 .chars_in_buffer = serial_chars_in_buffer,
1207 .tiocmget = serial_tiocmget,
1208 .tiocmset = serial_tiocmset,
1209 .get_icount = serial_get_icount,
1210 .cleanup = serial_cleanup,
1211 .install = serial_install,
1212 .proc_fops = &serial_proc_fops,
1213 };
1214
1215
1216 struct tty_driver *usb_serial_tty_driver;
1217
1218 static int __init usb_serial_init(void)
1219 {
1220 int i;
1221 int result;
1222
1223 usb_serial_tty_driver = alloc_tty_driver(SERIAL_TTY_MINORS);
1224 if (!usb_serial_tty_driver)
1225 return -ENOMEM;
1226
1227 /* Initialize our global data */
1228 for (i = 0; i < SERIAL_TTY_MINORS; ++i)
1229 serial_table[i] = NULL;
1230
1231 result = bus_register(&usb_serial_bus_type);
1232 if (result) {
1233 printk(KERN_ERR "usb-serial: %s - registering bus driver "
1234 "failed\n", __func__);
1235 goto exit_bus;
1236 }
1237
1238 usb_serial_tty_driver->owner = THIS_MODULE;
1239 usb_serial_tty_driver->driver_name = "usbserial";
1240 usb_serial_tty_driver->name = "ttyUSB";
1241 usb_serial_tty_driver->major = SERIAL_TTY_MAJOR;
1242 usb_serial_tty_driver->minor_start = 0;
1243 usb_serial_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
1244 usb_serial_tty_driver->subtype = SERIAL_TYPE_NORMAL;
1245 usb_serial_tty_driver->flags = TTY_DRIVER_REAL_RAW |
1246 TTY_DRIVER_DYNAMIC_DEV;
1247 usb_serial_tty_driver->init_termios = tty_std_termios;
1248 usb_serial_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD
1249 | HUPCL | CLOCAL;
1250 usb_serial_tty_driver->init_termios.c_ispeed = 9600;
1251 usb_serial_tty_driver->init_termios.c_ospeed = 9600;
1252 tty_set_operations(usb_serial_tty_driver, &serial_ops);
1253 result = tty_register_driver(usb_serial_tty_driver);
1254 if (result) {
1255 printk(KERN_ERR "usb-serial: %s - tty_register_driver failed\n",
1256 __func__);
1257 goto exit_reg_driver;
1258 }
1259
1260 /* register the USB driver */
1261 result = usb_register(&usb_serial_driver);
1262 if (result < 0) {
1263 printk(KERN_ERR "usb-serial: %s - usb_register failed\n",
1264 __func__);
1265 goto exit_tty;
1266 }
1267
1268 /* register the generic driver, if we should */
1269 result = usb_serial_generic_register(debug);
1270 if (result < 0) {
1271 printk(KERN_ERR "usb-serial: %s - registering generic "
1272 "driver failed\n", __func__);
1273 goto exit_generic;
1274 }
1275
1276 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");
1277
1278 return result;
1279
1280 exit_generic:
1281 usb_deregister(&usb_serial_driver);
1282
1283 exit_tty:
1284 tty_unregister_driver(usb_serial_tty_driver);
1285
1286 exit_reg_driver:
1287 bus_unregister(&usb_serial_bus_type);
1288
1289 exit_bus:
1290 printk(KERN_ERR "usb-serial: %s - returning with error %d\n",
1291 __func__, result);
1292 put_tty_driver(usb_serial_tty_driver);
1293 return result;
1294 }
1295
1296
1297 static void __exit usb_serial_exit(void)
1298 {
1299 usb_serial_console_exit();
1300
1301 usb_serial_generic_deregister();
1302
1303 usb_deregister(&usb_serial_driver);
1304 tty_unregister_driver(usb_serial_tty_driver);
1305 put_tty_driver(usb_serial_tty_driver);
1306 bus_unregister(&usb_serial_bus_type);
1307 }
1308
1309
1310 module_init(usb_serial_init);
1311 module_exit(usb_serial_exit);
1312
1313 #define set_to_generic_if_null(type, function) \
1314 do { \
1315 if (!type->function) { \
1316 type->function = usb_serial_generic_##function; \
1317 dbg("Had to override the " #function \
1318 " usb serial operation with the generic one.");\
1319 } \
1320 } while (0)
1321
1322 static void fixup_generic(struct usb_serial_driver *device)
1323 {
1324 set_to_generic_if_null(device, open);
1325 set_to_generic_if_null(device, write);
1326 set_to_generic_if_null(device, close);
1327 set_to_generic_if_null(device, write_room);
1328 set_to_generic_if_null(device, chars_in_buffer);
1329 set_to_generic_if_null(device, read_bulk_callback);
1330 set_to_generic_if_null(device, write_bulk_callback);
1331 set_to_generic_if_null(device, disconnect);
1332 set_to_generic_if_null(device, release);
1333 set_to_generic_if_null(device, process_read_urb);
1334 set_to_generic_if_null(device, prepare_write_buffer);
1335 }
1336
1337 int usb_serial_register(struct usb_serial_driver *driver)
1338 {
1339 /* must be called with BKL held */
1340 int retval;
1341
1342 if (usb_disabled())
1343 return -ENODEV;
1344
1345 fixup_generic(driver);
1346
1347 if (!driver->description)
1348 driver->description = driver->driver.name;
1349 if (!driver->usb_driver) {
1350 WARN(1, "Serial driver %s has no usb_driver\n",
1351 driver->description);
1352 return -EINVAL;
1353 }
1354 driver->usb_driver->supports_autosuspend = 1;
1355
1356 /* Add this device to our list of devices */
1357 mutex_lock(&table_lock);
1358 list_add(&driver->driver_list, &usb_serial_driver_list);
1359
1360 retval = usb_serial_bus_register(driver);
1361 if (retval) {
1362 printk(KERN_ERR "usb-serial: problem %d when registering "
1363 "driver %s\n", retval, driver->description);
1364 list_del(&driver->driver_list);
1365 } else
1366 printk(KERN_INFO "USB Serial support registered for %s\n",
1367 driver->description);
1368
1369 mutex_unlock(&table_lock);
1370 return retval;
1371 }
1372 EXPORT_SYMBOL_GPL(usb_serial_register);
1373
1374
1375 void usb_serial_deregister(struct usb_serial_driver *device)
1376 {
1377 /* must be called with BKL held */
1378 printk(KERN_INFO "USB Serial deregistering driver %s\n",
1379 device->description);
1380 mutex_lock(&table_lock);
1381 list_del(&device->driver_list);
1382 usb_serial_bus_deregister(device);
1383 mutex_unlock(&table_lock);
1384 }
1385 EXPORT_SYMBOL_GPL(usb_serial_deregister);
1386
1387 /* Module information */
1388 MODULE_AUTHOR(DRIVER_AUTHOR);
1389 MODULE_DESCRIPTION(DRIVER_DESC);
1390 MODULE_LICENSE("GPL");
1391
1392 module_param(debug, bool, S_IRUGO | S_IWUSR);
1393 MODULE_PARM_DESC(debug, "Debug enabled or not");
linux-next