xref: /linux/drivers/usb/class/usblp.c (revision 606d099cdd1080bbb50ea50dc52d98252f8f10a1)
1 /*
2  * usblp.c  Version 0.13
3  *
4  * Copyright (c) 1999 Michael Gee	<michael@linuxspecific.com>
5  * Copyright (c) 1999 Pavel Machek	<pavel@suse.cz>
6  * Copyright (c) 2000 Randy Dunlap	<rdunlap@xenotime.net>
7  * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
8  # Copyright (c) 2001 Pete Zaitcev	<zaitcev@redhat.com>
9  # Copyright (c) 2001 David Paschal	<paschal@rcsis.com>
10  * Copyright (c) 2006 Oliver Neukum	<oliver@neukum.name>
11  *
12  * USB Printer Device Class driver for USB printers and printer cables
13  *
14  * Sponsored by SuSE
15  *
16  * ChangeLog:
17  *	v0.1 - thorough cleaning, URBification, almost a rewrite
18  *	v0.2 - some more cleanups
19  *	v0.3 - cleaner again, waitqueue fixes
20  *	v0.4 - fixes in unidirectional mode
21  *	v0.5 - add DEVICE_ID string support
22  *	v0.6 - never time out
23  *	v0.7 - fixed bulk-IN read and poll (David Paschal)
24  *	v0.8 - add devfs support
25  *	v0.9 - fix unplug-while-open paths
26  *	v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
27  *	v0.11 - add proto_bias option (Pete Zaitcev)
28  *	v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
29  *	v0.13 - alloc space for statusbuf (<status> not on stack);
30  *		use usb_buffer_alloc() for read buf & write buf;
31  */
32 
33 /*
34  * This program is free software; you can redistribute it and/or modify
35  * it under the terms of the GNU General Public License as published by
36  * the Free Software Foundation; either version 2 of the License, or
37  * (at your option) any later version.
38  *
39  * This program is distributed in the hope that it will be useful,
40  * but WITHOUT ANY WARRANTY; without even the implied warranty of
41  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
42  * GNU General Public License for more details.
43  *
44  * You should have received a copy of the GNU General Public License
45  * along with this program; if not, write to the Free Software
46  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
47  */
48 
49 #include <linux/module.h>
50 #include <linux/kernel.h>
51 #include <linux/sched.h>
52 #include <linux/smp_lock.h>
53 #include <linux/signal.h>
54 #include <linux/poll.h>
55 #include <linux/init.h>
56 #include <linux/slab.h>
57 #include <linux/lp.h>
58 #include <linux/mutex.h>
59 #undef DEBUG
60 #include <linux/usb.h>
61 
62 /*
63  * Version Information
64  */
65 #define DRIVER_VERSION "v0.13"
66 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
67 #define DRIVER_DESC "USB Printer Device Class driver"
68 
69 #define USBLP_BUF_SIZE		8192
70 #define USBLP_DEVICE_ID_SIZE	1024
71 
72 /* ioctls: */
73 #define LPGETSTATUS		0x060b		/* same as in drivers/char/lp.c */
74 #define IOCNR_GET_DEVICE_ID		1
75 #define IOCNR_GET_PROTOCOLS		2
76 #define IOCNR_SET_PROTOCOL		3
77 #define IOCNR_HP_SET_CHANNEL		4
78 #define IOCNR_GET_BUS_ADDRESS		5
79 #define IOCNR_GET_VID_PID		6
80 #define IOCNR_SOFT_RESET		7
81 /* Get device_id string: */
82 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
83 /* The following ioctls were added for http://hpoj.sourceforge.net: */
84 /* Get two-int array:
85  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
86  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
87 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
88 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
89 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
90 /* Set channel number (HP Vendor-specific command): */
91 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
92 /* Get two-int array: [0]=bus number, [1]=device address: */
93 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
94 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
95 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
96 /* Perform class specific soft reset */
97 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
98 
99 /*
100  * A DEVICE_ID string may include the printer's serial number.
101  * It should end with a semi-colon (';').
102  * An example from an HP 970C DeskJet printer is (this is one long string,
103  * with the serial number changed):
104 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
105  */
106 
107 /*
108  * USB Printer Requests
109  */
110 
111 #define USBLP_REQ_GET_ID			0x00
112 #define USBLP_REQ_GET_STATUS			0x01
113 #define USBLP_REQ_RESET				0x02
114 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST	0x00	/* HP Vendor-specific */
115 
116 #define USBLP_MINORS		16
117 #define USBLP_MINOR_BASE	0
118 
119 #define USBLP_WRITE_TIMEOUT	(5000)			/* 5 seconds */
120 
121 #define USBLP_FIRST_PROTOCOL	1
122 #define USBLP_LAST_PROTOCOL	3
123 #define USBLP_MAX_PROTOCOLS	(USBLP_LAST_PROTOCOL+1)
124 
125 /*
126  * some arbitrary status buffer size;
127  * need a status buffer that is allocated via kmalloc(), not on stack
128  */
129 #define STATUS_BUF_SIZE		8
130 
131 struct usblp {
132 	struct usb_device 	*dev;			/* USB device */
133 	struct semaphore	sem;			/* locks this struct, especially "dev" */
134 	char			*writebuf;		/* write transfer_buffer */
135 	char			*readbuf;		/* read transfer_buffer */
136 	char			*statusbuf;		/* status transfer_buffer */
137 	struct urb		*readurb, *writeurb;	/* The urbs */
138 	wait_queue_head_t	wait;			/* Zzzzz ... */
139 	int			readcount;		/* Counter for reads */
140 	int			ifnum;			/* Interface number */
141 	struct usb_interface	*intf;			/* The interface */
142 	/* Alternate-setting numbers and endpoints for each protocol
143 	 * (7/1/{index=1,2,3}) that the device supports: */
144 	struct {
145 		int				alt_setting;
146 		struct usb_endpoint_descriptor	*epwrite;
147 		struct usb_endpoint_descriptor	*epread;
148 	}			protocol[USBLP_MAX_PROTOCOLS];
149 	int			current_protocol;
150 	int			minor;			/* minor number of device */
151 	int			wcomplete;		/* writing is completed */
152 	int			rcomplete;		/* reading is completed */
153 	unsigned int		quirks;			/* quirks flags */
154 	unsigned char		used;			/* True if open */
155 	unsigned char		present;		/* True if not disconnected */
156 	unsigned char		bidir;			/* interface is bidirectional */
157 	unsigned char		sleeping;		/* interface is suspended */
158 	unsigned char		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
159 							/* first 2 bytes are (big-endian) length */
160 };
161 
162 #ifdef DEBUG
163 static void usblp_dump(struct usblp *usblp) {
164 	int p;
165 
166 	dbg("usblp=0x%p", usblp);
167 	dbg("dev=0x%p", usblp->dev);
168 	dbg("present=%d", usblp->present);
169 	dbg("readbuf=0x%p", usblp->readbuf);
170 	dbg("writebuf=0x%p", usblp->writebuf);
171 	dbg("readurb=0x%p", usblp->readurb);
172 	dbg("writeurb=0x%p", usblp->writeurb);
173 	dbg("readcount=%d", usblp->readcount);
174 	dbg("ifnum=%d", usblp->ifnum);
175     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
176 	dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
177 	dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
178 	dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
179     }
180 	dbg("current_protocol=%d", usblp->current_protocol);
181 	dbg("minor=%d", usblp->minor);
182 	dbg("wcomplete=%d", usblp->wcomplete);
183 	dbg("rcomplete=%d", usblp->rcomplete);
184 	dbg("quirks=%d", usblp->quirks);
185 	dbg("used=%d", usblp->used);
186 	dbg("bidir=%d", usblp->bidir);
187 	dbg("sleeping=%d", usblp->sleeping);
188 	dbg("device_id_string=\"%s\"",
189 		usblp->device_id_string ?
190 			usblp->device_id_string + 2 :
191 			(unsigned char *)"(null)");
192 }
193 #endif
194 
195 /* Quirks: various printer quirks are handled by this table & its flags. */
196 
197 struct quirk_printer_struct {
198 	__u16 vendorId;
199 	__u16 productId;
200 	unsigned int quirks;
201 };
202 
203 #define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
204 #define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */
205 
206 static const struct quirk_printer_struct quirk_printers[] = {
207 	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
208 	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
209 	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
210 	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
211 	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
212 	{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
213 	{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
214 	{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
215 	{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
216 	{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
217 	{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
218 	{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
219 	{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
220 	{ 0, 0 }
221 };
222 
223 static int usblp_select_alts(struct usblp *usblp);
224 static int usblp_set_protocol(struct usblp *usblp, int protocol);
225 static int usblp_cache_device_id_string(struct usblp *usblp);
226 
227 /* forward reference to make our lives easier */
228 static struct usb_driver usblp_driver;
229 static DEFINE_MUTEX(usblp_mutex);	/* locks the existence of usblp's */
230 
231 /*
232  * Functions for usblp control messages.
233  */
234 
235 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
236 {
237 	int retval;
238 	int index = usblp->ifnum;
239 
240 	/* High byte has the interface index.
241 	   Low byte has the alternate setting.
242 	 */
243 	if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
244 	  index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
245 	}
246 
247 	retval = usb_control_msg(usblp->dev,
248 		dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
249 		request, type | dir | recip, value, index, buf, len, USBLP_WRITE_TIMEOUT);
250 	dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
251 		request, !!dir, recip, value, index, len, retval);
252 	return retval < 0 ? retval : 0;
253 }
254 
255 #define usblp_read_status(usblp, status)\
256 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
257 #define usblp_get_id(usblp, config, id, maxlen)\
258 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
259 #define usblp_reset(usblp)\
260 	usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
261 
262 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
263 	usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
264 
265 /*
266  * See the description for usblp_select_alts() below for the usage
267  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
268  * case of any trouble.
269  */
270 static int proto_bias = -1;
271 
272 /*
273  * URB callback.
274  */
275 
276 static void usblp_bulk_read(struct urb *urb)
277 {
278 	struct usblp *usblp = urb->context;
279 
280 	if (unlikely(!usblp || !usblp->dev || !usblp->used))
281 		return;
282 
283 	if (unlikely(!usblp->present))
284 		goto unplug;
285 	if (unlikely(urb->status))
286 		warn("usblp%d: nonzero read/write bulk status received: %d",
287 			usblp->minor, urb->status);
288 	usblp->rcomplete = 1;
289 unplug:
290 	wake_up_interruptible(&usblp->wait);
291 }
292 
293 static void usblp_bulk_write(struct urb *urb)
294 {
295 	struct usblp *usblp = urb->context;
296 
297 	if (unlikely(!usblp || !usblp->dev || !usblp->used))
298 		return;
299 	if (unlikely(!usblp->present))
300 		goto unplug;
301 	if (unlikely(urb->status))
302 		warn("usblp%d: nonzero read/write bulk status received: %d",
303 			usblp->minor, urb->status);
304 	usblp->wcomplete = 1;
305 unplug:
306 	wake_up_interruptible(&usblp->wait);
307 }
308 
309 /*
310  * Get and print printer errors.
311  */
312 
313 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
314 
315 static int usblp_check_status(struct usblp *usblp, int err)
316 {
317 	unsigned char status, newerr = 0;
318 	int error;
319 
320 	error = usblp_read_status (usblp, usblp->statusbuf);
321 	if (error < 0) {
322 		if (printk_ratelimit())
323 			err("usblp%d: error %d reading printer status",
324 				usblp->minor, error);
325 		return 0;
326 	}
327 
328 	status = *usblp->statusbuf;
329 
330 	if (~status & LP_PERRORP)
331 		newerr = 3;
332 	if (status & LP_POUTPA)
333 		newerr = 1;
334 	if (~status & LP_PSELECD)
335 		newerr = 2;
336 
337 	if (newerr != err)
338 		info("usblp%d: %s", usblp->minor, usblp_messages[newerr]);
339 
340 	return newerr;
341 }
342 
343 static int handle_bidir (struct usblp *usblp)
344 {
345 	if (usblp->bidir && usblp->used && !usblp->sleeping) {
346 		usblp->readcount = 0;
347 		usblp->readurb->dev = usblp->dev;
348 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0) {
349 			usblp->used = 0;
350 			return -EIO;
351 		}
352 	}
353 
354 	return 0;
355 }
356 
357 /*
358  * File op functions.
359  */
360 
361 static int usblp_open(struct inode *inode, struct file *file)
362 {
363 	int minor = iminor(inode);
364 	struct usblp *usblp;
365 	struct usb_interface *intf;
366 	int retval;
367 
368 	if (minor < 0)
369 		return -ENODEV;
370 
371 	mutex_lock (&usblp_mutex);
372 
373 	retval = -ENODEV;
374 	intf = usb_find_interface(&usblp_driver, minor);
375 	if (!intf) {
376 		goto out;
377 	}
378 	usblp = usb_get_intfdata (intf);
379 	if (!usblp || !usblp->dev || !usblp->present)
380 		goto out;
381 
382 	retval = -EBUSY;
383 	if (usblp->used)
384 		goto out;
385 
386 	/*
387 	 * TODO: need to implement LP_ABORTOPEN + O_NONBLOCK as in drivers/char/lp.c ???
388 	 * This is #if 0-ed because we *don't* want to fail an open
389 	 * just because the printer is off-line.
390 	 */
391 #if 0
392 	if ((retval = usblp_check_status(usblp, 0))) {
393 		retval = retval > 1 ? -EIO : -ENOSPC;
394 		goto out;
395 	}
396 #else
397 	retval = 0;
398 #endif
399 
400 	usblp->used = 1;
401 	file->private_data = usblp;
402 
403 	usblp->writeurb->transfer_buffer_length = 0;
404 	usblp->wcomplete = 1; /* we begin writeable */
405 	usblp->rcomplete = 0;
406 	usblp->writeurb->status = 0;
407 	usblp->readurb->status = 0;
408 
409 	if (handle_bidir(usblp) < 0) {
410 		file->private_data = NULL;
411 		retval = -EIO;
412 	}
413 out:
414 	mutex_unlock (&usblp_mutex);
415 	return retval;
416 }
417 
418 static void usblp_cleanup (struct usblp *usblp)
419 {
420 	info("usblp%d: removed", usblp->minor);
421 
422 	kfree (usblp->device_id_string);
423 	kfree (usblp->statusbuf);
424 	usb_free_urb(usblp->writeurb);
425 	usb_free_urb(usblp->readurb);
426 	kfree (usblp);
427 }
428 
429 static void usblp_unlink_urbs(struct usblp *usblp)
430 {
431 	usb_kill_urb(usblp->writeurb);
432 	if (usblp->bidir)
433 		usb_kill_urb(usblp->readurb);
434 }
435 
436 static int usblp_release(struct inode *inode, struct file *file)
437 {
438 	struct usblp *usblp = file->private_data;
439 
440 	mutex_lock (&usblp_mutex);
441 	usblp->used = 0;
442 	if (usblp->present) {
443 		usblp_unlink_urbs(usblp);
444 	} else 		/* finish cleanup from disconnect */
445 		usblp_cleanup (usblp);
446 	mutex_unlock (&usblp_mutex);
447 	return 0;
448 }
449 
450 /* No kernel lock - fine */
451 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
452 {
453 	struct usblp *usblp = file->private_data;
454 	poll_wait(file, &usblp->wait, wait);
455  	return ((!usblp->bidir || !usblp->rcomplete) ? 0 : POLLIN  | POLLRDNORM)
456  			       | (!usblp->wcomplete ? 0 : POLLOUT | POLLWRNORM);
457 }
458 
459 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
460 {
461 	struct usblp *usblp = file->private_data;
462 	int length, err, i;
463 	unsigned char newChannel;
464 	int status;
465 	int twoints[2];
466 	int retval = 0;
467 
468 	down (&usblp->sem);
469 	if (!usblp->present) {
470 		retval = -ENODEV;
471 		goto done;
472 	}
473 
474 	if (usblp->sleeping) {
475 		retval = -ENODEV;
476 		goto done;
477 	}
478 
479 	dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
480 		_IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
481 
482 	if (_IOC_TYPE(cmd) == 'P')	/* new-style ioctl number */
483 
484 		switch (_IOC_NR(cmd)) {
485 
486 			case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
487 				if (_IOC_DIR(cmd) != _IOC_READ) {
488 					retval = -EINVAL;
489 					goto done;
490 				}
491 
492 				length = usblp_cache_device_id_string(usblp);
493 				if (length < 0) {
494 					retval = length;
495 					goto done;
496 				}
497 				if (length > _IOC_SIZE(cmd))
498 					length = _IOC_SIZE(cmd); /* truncate */
499 
500 				if (copy_to_user((void __user *) arg,
501 						usblp->device_id_string,
502 						(unsigned long) length)) {
503 					retval = -EFAULT;
504 					goto done;
505 				}
506 
507 				break;
508 
509 			case IOCNR_GET_PROTOCOLS:
510 				if (_IOC_DIR(cmd) != _IOC_READ ||
511 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
512 					retval = -EINVAL;
513 					goto done;
514 				}
515 
516 				twoints[0] = usblp->current_protocol;
517 				twoints[1] = 0;
518 				for (i = USBLP_FIRST_PROTOCOL;
519 				     i <= USBLP_LAST_PROTOCOL; i++) {
520 					if (usblp->protocol[i].alt_setting >= 0)
521 						twoints[1] |= (1<<i);
522 				}
523 
524 				if (copy_to_user((void __user *)arg,
525 						(unsigned char *)twoints,
526 						sizeof(twoints))) {
527 					retval = -EFAULT;
528 					goto done;
529 				}
530 
531 				break;
532 
533 			case IOCNR_SET_PROTOCOL:
534 				if (_IOC_DIR(cmd) != _IOC_WRITE) {
535 					retval = -EINVAL;
536 					goto done;
537 				}
538 
539 #ifdef DEBUG
540 				if (arg == -10) {
541 					usblp_dump(usblp);
542 					break;
543 				}
544 #endif
545 
546 				usblp_unlink_urbs(usblp);
547 				retval = usblp_set_protocol(usblp, arg);
548 				if (retval < 0) {
549 					usblp_set_protocol(usblp,
550 						usblp->current_protocol);
551 				}
552 				break;
553 
554 			case IOCNR_HP_SET_CHANNEL:
555 				if (_IOC_DIR(cmd) != _IOC_WRITE ||
556 				    le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
557 				    usblp->quirks & USBLP_QUIRK_BIDIR) {
558 					retval = -EINVAL;
559 					goto done;
560 				}
561 
562 				err = usblp_hp_channel_change_request(usblp,
563 					arg, &newChannel);
564 				if (err < 0) {
565 					err("usblp%d: error = %d setting "
566 						"HP channel",
567 						usblp->minor, err);
568 					retval = -EIO;
569 					goto done;
570 				}
571 
572 				dbg("usblp%d requested/got HP channel %ld/%d",
573 					usblp->minor, arg, newChannel);
574 				break;
575 
576 			case IOCNR_GET_BUS_ADDRESS:
577 				if (_IOC_DIR(cmd) != _IOC_READ ||
578 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
579 					retval = -EINVAL;
580 					goto done;
581 				}
582 
583 				twoints[0] = usblp->dev->bus->busnum;
584 				twoints[1] = usblp->dev->devnum;
585 				if (copy_to_user((void __user *)arg,
586 						(unsigned char *)twoints,
587 						sizeof(twoints))) {
588 					retval = -EFAULT;
589 					goto done;
590 				}
591 
592 				dbg("usblp%d is bus=%d, device=%d",
593 					usblp->minor, twoints[0], twoints[1]);
594 				break;
595 
596 			case IOCNR_GET_VID_PID:
597 				if (_IOC_DIR(cmd) != _IOC_READ ||
598 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
599 					retval = -EINVAL;
600 					goto done;
601 				}
602 
603 				twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
604 				twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
605 				if (copy_to_user((void __user *)arg,
606 						(unsigned char *)twoints,
607 						sizeof(twoints))) {
608 					retval = -EFAULT;
609 					goto done;
610 				}
611 
612 				dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
613 					usblp->minor, twoints[0], twoints[1]);
614 				break;
615 
616 			case IOCNR_SOFT_RESET:
617 				if (_IOC_DIR(cmd) != _IOC_NONE) {
618 					retval = -EINVAL;
619 					goto done;
620 				}
621 				retval = usblp_reset(usblp);
622 				break;
623 			default:
624 				retval = -ENOTTY;
625 		}
626 	else	/* old-style ioctl value */
627 		switch (cmd) {
628 
629 			case LPGETSTATUS:
630 				if (usblp_read_status(usblp, usblp->statusbuf)) {
631 					if (printk_ratelimit())
632 						err("usblp%d: failed reading printer status",
633 							usblp->minor);
634 					retval = -EIO;
635 					goto done;
636 				}
637 				status = *usblp->statusbuf;
638 				if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
639 					retval = -EFAULT;
640 				break;
641 
642 			default:
643 				retval = -ENOTTY;
644 		}
645 
646 done:
647 	up (&usblp->sem);
648 	return retval;
649 }
650 
651 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
652 {
653 	struct usblp *usblp = file->private_data;
654 	int timeout, rv, err = 0, transfer_length = 0;
655 	size_t writecount = 0;
656 
657 	while (writecount < count) {
658 		if (!usblp->wcomplete) {
659 			barrier();
660 			if (file->f_flags & O_NONBLOCK) {
661 				writecount += transfer_length;
662 				return writecount ? writecount : -EAGAIN;
663 			}
664 
665 			timeout = USBLP_WRITE_TIMEOUT;
666 
667 			rv = wait_event_interruptible_timeout(usblp->wait, usblp->wcomplete || !usblp->present , timeout);
668 			if (rv < 0)
669 				return writecount ? writecount : -EINTR;
670 		}
671 		down (&usblp->sem);
672 		if (!usblp->present) {
673 			up (&usblp->sem);
674 			return -ENODEV;
675 		}
676 
677 		if (usblp->sleeping) {
678 			up (&usblp->sem);
679 			return writecount ? writecount : -ENODEV;
680 		}
681 
682 		if (usblp->writeurb->status != 0) {
683 			if (usblp->quirks & USBLP_QUIRK_BIDIR) {
684 				if (!usblp->wcomplete)
685 					err("usblp%d: error %d writing to printer",
686 						usblp->minor, usblp->writeurb->status);
687 				err = usblp->writeurb->status;
688 			} else
689 				err = usblp_check_status(usblp, err);
690 			up (&usblp->sem);
691 
692 			/* if the fault was due to disconnect, let khubd's
693 			 * call to usblp_disconnect() grab usblp->sem ...
694 			 */
695 			schedule ();
696 			continue;
697 		}
698 
699 		/* We must increment writecount here, and not at the
700 		 * end of the loop. Otherwise, the final loop iteration may
701 		 * be skipped, leading to incomplete printer output.
702 		 */
703 		writecount += transfer_length;
704 		if (writecount == count) {
705 			up(&usblp->sem);
706 			break;
707 		}
708 
709 		transfer_length=(count - writecount);
710 		if (transfer_length > USBLP_BUF_SIZE)
711 			transfer_length = USBLP_BUF_SIZE;
712 
713 		usblp->writeurb->transfer_buffer_length = transfer_length;
714 
715 		if (copy_from_user(usblp->writeurb->transfer_buffer,
716 				   buffer + writecount, transfer_length)) {
717 			up(&usblp->sem);
718 			return writecount ? writecount : -EFAULT;
719 		}
720 
721 		usblp->writeurb->dev = usblp->dev;
722 		usblp->wcomplete = 0;
723 		err = usb_submit_urb(usblp->writeurb, GFP_KERNEL);
724 		if (err) {
725 			usblp->wcomplete = 1;
726 			if (err != -ENOMEM)
727 				count = -EIO;
728 			else
729 				count = writecount ? writecount : -ENOMEM;
730 			up (&usblp->sem);
731 			break;
732 		}
733 		up (&usblp->sem);
734 	}
735 
736 	return count;
737 }
738 
739 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
740 {
741 	struct usblp *usblp = file->private_data;
742 	int rv;
743 
744 	if (!usblp->bidir)
745 		return -EINVAL;
746 
747 	down (&usblp->sem);
748 	if (!usblp->present) {
749 		count = -ENODEV;
750 		goto done;
751 	}
752 
753 	if (!usblp->rcomplete) {
754 		barrier();
755 
756 		if (file->f_flags & O_NONBLOCK) {
757 			count = -EAGAIN;
758 			goto done;
759 		}
760 		up(&usblp->sem);
761 		rv = wait_event_interruptible(usblp->wait, usblp->rcomplete || !usblp->present);
762 		down(&usblp->sem);
763 		if (rv < 0) {
764 			count = -EINTR;
765 			goto done;
766 		}
767 	}
768 
769 	if (!usblp->present) {
770 		count = -ENODEV;
771 		goto done;
772 	}
773 
774 	if (usblp->sleeping) {
775 		count = -ENODEV;
776 		goto done;
777 	}
778 
779 	if (usblp->readurb->status) {
780 		err("usblp%d: error %d reading from printer",
781 			usblp->minor, usblp->readurb->status);
782 		usblp->readurb->dev = usblp->dev;
783  		usblp->readcount = 0;
784 		usblp->rcomplete = 0;
785 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0)
786 			dbg("error submitting urb");
787 		count = -EIO;
788 		goto done;
789 	}
790 
791 	count = count < usblp->readurb->actual_length - usblp->readcount ?
792 		count :	usblp->readurb->actual_length - usblp->readcount;
793 
794 	if (copy_to_user(buffer, usblp->readurb->transfer_buffer + usblp->readcount, count)) {
795 		count = -EFAULT;
796 		goto done;
797 	}
798 
799 	if ((usblp->readcount += count) == usblp->readurb->actual_length) {
800 		usblp->readcount = 0;
801 		usblp->readurb->dev = usblp->dev;
802 		usblp->rcomplete = 0;
803 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL)) {
804 			count = -EIO;
805 			goto done;
806 		}
807 	}
808 
809 done:
810 	up (&usblp->sem);
811 	return count;
812 }
813 
814 /*
815  * Checks for printers that have quirks, such as requiring unidirectional
816  * communication but reporting bidirectional; currently some HP printers
817  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
818  * sent at each open (like some Epsons).
819  * Returns 1 if found, 0 if not found.
820  *
821  * HP recommended that we use the bidirectional interface but
822  * don't attempt any bulk IN transfers from the IN endpoint.
823  * Here's some more detail on the problem:
824  * The problem is not that it isn't bidirectional though. The problem
825  * is that if you request a device ID, or status information, while
826  * the buffers are full, the return data will end up in the print data
827  * buffer. For example if you make sure you never request the device ID
828  * while you are sending print data, and you don't try to query the
829  * printer status every couple of milliseconds, you will probably be OK.
830  */
831 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
832 {
833 	int i;
834 
835 	for (i = 0; quirk_printers[i].vendorId; i++) {
836 		if (vendor == quirk_printers[i].vendorId &&
837 		    product == quirk_printers[i].productId)
838 			return quirk_printers[i].quirks;
839  	}
840 	return 0;
841 }
842 
843 static const struct file_operations usblp_fops = {
844 	.owner =	THIS_MODULE,
845 	.read =		usblp_read,
846 	.write =	usblp_write,
847 	.poll =		usblp_poll,
848 	.unlocked_ioctl =	usblp_ioctl,
849 	.compat_ioctl =		usblp_ioctl,
850 	.open =		usblp_open,
851 	.release =	usblp_release,
852 };
853 
854 static struct usb_class_driver usblp_class = {
855 	.name =		"lp%d",
856 	.fops =		&usblp_fops,
857 	.minor_base =	USBLP_MINOR_BASE,
858 };
859 
860 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
861 {
862 	struct usb_interface *intf = to_usb_interface(dev);
863 	struct usblp *usblp = usb_get_intfdata (intf);
864 
865 	if (usblp->device_id_string[0] == 0 &&
866 	    usblp->device_id_string[1] == 0)
867 		return 0;
868 
869 	return sprintf(buf, "%s", usblp->device_id_string+2);
870 }
871 
872 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
873 
874 static int usblp_probe(struct usb_interface *intf,
875 		       const struct usb_device_id *id)
876 {
877 	struct usb_device *dev = interface_to_usbdev (intf);
878 	struct usblp *usblp = NULL;
879 	int protocol;
880 	int retval;
881 
882 	/* Malloc and start initializing usblp structure so we can use it
883 	 * directly. */
884 	if (!(usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL))) {
885 		err("out of memory for usblp");
886 		goto abort;
887 	}
888 	usblp->dev = dev;
889 	init_MUTEX (&usblp->sem);
890 	init_waitqueue_head(&usblp->wait);
891 	usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
892 	usblp->intf = intf;
893 
894 	usblp->writeurb = usb_alloc_urb(0, GFP_KERNEL);
895 	if (!usblp->writeurb) {
896 		err("out of memory");
897 		goto abort;
898 	}
899 	usblp->readurb = usb_alloc_urb(0, GFP_KERNEL);
900 	if (!usblp->readurb) {
901 		err("out of memory");
902 		goto abort;
903 	}
904 
905 	/* Malloc device ID string buffer to the largest expected length,
906 	 * since we can re-query it on an ioctl and a dynamic string
907 	 * could change in length. */
908 	if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
909 		err("out of memory for device_id_string");
910 		goto abort;
911 	}
912 
913 	usblp->writebuf = usblp->readbuf = NULL;
914 	usblp->writeurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
915 	usblp->readurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
916 	/* Malloc write & read buffers.  We somewhat wastefully
917 	 * malloc both regardless of bidirectionality, because the
918 	 * alternate setting can be changed later via an ioctl. */
919 	if (!(usblp->writebuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
920 				GFP_KERNEL, &usblp->writeurb->transfer_dma))) {
921 		err("out of memory for write buf");
922 		goto abort;
923 	}
924 	if (!(usblp->readbuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
925 				GFP_KERNEL, &usblp->readurb->transfer_dma))) {
926 		err("out of memory for read buf");
927 		goto abort;
928 	}
929 
930 	/* Allocate buffer for printer status */
931 	usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
932 	if (!usblp->statusbuf) {
933 		err("out of memory for statusbuf");
934 		goto abort;
935 	}
936 
937 	/* Lookup quirks for this printer. */
938 	usblp->quirks = usblp_quirks(
939 		le16_to_cpu(dev->descriptor.idVendor),
940 		le16_to_cpu(dev->descriptor.idProduct));
941 
942 	/* Analyze and pick initial alternate settings and endpoints. */
943 	protocol = usblp_select_alts(usblp);
944 	if (protocol < 0) {
945 		dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
946 			le16_to_cpu(dev->descriptor.idVendor),
947 			le16_to_cpu(dev->descriptor.idProduct));
948 		goto abort;
949 	}
950 
951 	/* Setup the selected alternate setting and endpoints. */
952 	if (usblp_set_protocol(usblp, protocol) < 0)
953 		goto abort;
954 
955 	/* Retrieve and store the device ID string. */
956 	usblp_cache_device_id_string(usblp);
957 	retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
958 	if (retval)
959 		goto abort_intfdata;
960 
961 #ifdef DEBUG
962 	usblp_check_status(usblp, 0);
963 #endif
964 
965 	usb_set_intfdata (intf, usblp);
966 
967 	usblp->present = 1;
968 
969 	retval = usb_register_dev(intf, &usblp_class);
970 	if (retval) {
971 		err("Not able to get a minor for this device.");
972 		goto abort_intfdata;
973 	}
974 	usblp->minor = intf->minor;
975 	info("usblp%d: USB %sdirectional printer dev %d "
976 		"if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X",
977 		usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
978 		usblp->ifnum,
979 		usblp->protocol[usblp->current_protocol].alt_setting,
980 		usblp->current_protocol,
981 		le16_to_cpu(usblp->dev->descriptor.idVendor),
982 		le16_to_cpu(usblp->dev->descriptor.idProduct));
983 
984 	return 0;
985 
986 abort_intfdata:
987 	usb_set_intfdata (intf, NULL);
988 	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
989 abort:
990 	if (usblp) {
991 		if (usblp->writebuf)
992 			usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
993 				usblp->writebuf, usblp->writeurb->transfer_dma);
994 		if (usblp->readbuf)
995 			usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
996 				usblp->readbuf, usblp->writeurb->transfer_dma);
997 		kfree(usblp->statusbuf);
998 		kfree(usblp->device_id_string);
999 		usb_free_urb(usblp->writeurb);
1000 		usb_free_urb(usblp->readurb);
1001 		kfree(usblp);
1002 	}
1003 	return -EIO;
1004 }
1005 
1006 /*
1007  * We are a "new" style driver with usb_device_id table,
1008  * but our requirements are too intricate for simple match to handle.
1009  *
1010  * The "proto_bias" option may be used to specify the preferred protocol
1011  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1012  * supports the preferred protocol, then we bind to it.
1013  *
1014  * The best interface for us is 7/1/2, because it is compatible
1015  * with a stream of characters. If we find it, we bind to it.
1016  *
1017  * Note that the people from hpoj.sourceforge.net need to be able to
1018  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1019  *
1020  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1021  * stream-compatible, because this matches the behaviour of the old code.
1022  *
1023  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1024  */
1025 static int usblp_select_alts(struct usblp *usblp)
1026 {
1027 	struct usb_interface *if_alt;
1028 	struct usb_host_interface *ifd;
1029 	struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1030 	int p, i, e;
1031 
1032 	if_alt = usblp->intf;
1033 
1034 	for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1035 		usblp->protocol[p].alt_setting = -1;
1036 
1037 	/* Find out what we have. */
1038 	for (i = 0; i < if_alt->num_altsetting; i++) {
1039 		ifd = &if_alt->altsetting[i];
1040 
1041 		if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1042 			continue;
1043 
1044 		if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1045 		    ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1046 			continue;
1047 
1048 		/* Look for bulk OUT and IN endpoints. */
1049 		epwrite = epread = NULL;
1050 		for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1051 			epd = &ifd->endpoint[e].desc;
1052 
1053 			if (usb_endpoint_is_bulk_out(epd))
1054 				if (!epwrite)
1055 					epwrite = epd;
1056 
1057 			if (usb_endpoint_is_bulk_in(epd))
1058 				if (!epread)
1059 					epread = epd;
1060 		}
1061 
1062 		/* Ignore buggy hardware without the right endpoints. */
1063 		if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1064 			continue;
1065 
1066 		/* Turn off reads for 7/1/1 (unidirectional) interfaces
1067 		 * and buggy bidirectional printers. */
1068 		if (ifd->desc.bInterfaceProtocol == 1) {
1069 			epread = NULL;
1070 		} else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1071 			info("Disabling reads from problem bidirectional "
1072 				"printer on usblp%d", usblp->minor);
1073 			epread = NULL;
1074 		}
1075 
1076 		usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1077 				ifd->desc.bAlternateSetting;
1078 		usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1079 		usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1080 	}
1081 
1082 	/* If our requested protocol is supported, then use it. */
1083 	if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1084 	    proto_bias <= USBLP_LAST_PROTOCOL &&
1085 	    usblp->protocol[proto_bias].alt_setting != -1)
1086 		return proto_bias;
1087 
1088 	/* Ordering is important here. */
1089 	if (usblp->protocol[2].alt_setting != -1)
1090 		return 2;
1091 	if (usblp->protocol[1].alt_setting != -1)
1092 		return 1;
1093 	if (usblp->protocol[3].alt_setting != -1)
1094 		return 3;
1095 
1096 	/* If nothing is available, then don't bind to this device. */
1097 	return -1;
1098 }
1099 
1100 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1101 {
1102 	int r, alts;
1103 
1104 	if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1105 		return -EINVAL;
1106 
1107 	alts = usblp->protocol[protocol].alt_setting;
1108 	if (alts < 0)
1109 		return -EINVAL;
1110 	r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1111 	if (r < 0) {
1112 		err("can't set desired altsetting %d on interface %d",
1113 			alts, usblp->ifnum);
1114 		return r;
1115 	}
1116 
1117 	usb_fill_bulk_urb(usblp->writeurb, usblp->dev,
1118 		usb_sndbulkpipe(usblp->dev,
1119 		  usblp->protocol[protocol].epwrite->bEndpointAddress),
1120 		usblp->writebuf, 0,
1121 		usblp_bulk_write, usblp);
1122 
1123 	usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1124 	if (usblp->bidir)
1125 		usb_fill_bulk_urb(usblp->readurb, usblp->dev,
1126 			usb_rcvbulkpipe(usblp->dev,
1127 			  usblp->protocol[protocol].epread->bEndpointAddress),
1128 			usblp->readbuf, USBLP_BUF_SIZE,
1129 			usblp_bulk_read, usblp);
1130 
1131 	usblp->current_protocol = protocol;
1132 	dbg("usblp%d set protocol %d", usblp->minor, protocol);
1133 	return 0;
1134 }
1135 
1136 /* Retrieves and caches device ID string.
1137  * Returns length, including length bytes but not null terminator.
1138  * On error, returns a negative errno value. */
1139 static int usblp_cache_device_id_string(struct usblp *usblp)
1140 {
1141 	int err, length;
1142 
1143 	err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1144 	if (err < 0) {
1145 		dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1146 			usblp->minor, err);
1147 		usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1148 		return -EIO;
1149 	}
1150 
1151 	/* First two bytes are length in big-endian.
1152 	 * They count themselves, and we copy them into
1153 	 * the user's buffer. */
1154 	length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1155 	if (length < 2)
1156 		length = 2;
1157 	else if (length >= USBLP_DEVICE_ID_SIZE)
1158 		length = USBLP_DEVICE_ID_SIZE - 1;
1159 	usblp->device_id_string[length] = '\0';
1160 
1161 	dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1162 		usblp->minor, length, &usblp->device_id_string[2]);
1163 
1164 	return length;
1165 }
1166 
1167 static void usblp_disconnect(struct usb_interface *intf)
1168 {
1169 	struct usblp *usblp = usb_get_intfdata (intf);
1170 
1171 	usb_deregister_dev(intf, &usblp_class);
1172 
1173 	if (!usblp || !usblp->dev) {
1174 		err("bogus disconnect");
1175 		BUG ();
1176 	}
1177 
1178 	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1179 
1180 	mutex_lock (&usblp_mutex);
1181 	down (&usblp->sem);
1182 	usblp->present = 0;
1183 	usb_set_intfdata (intf, NULL);
1184 
1185 	usblp_unlink_urbs(usblp);
1186 	usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1187 			usblp->writebuf, usblp->writeurb->transfer_dma);
1188 	usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1189 			usblp->readbuf, usblp->readurb->transfer_dma);
1190 	up (&usblp->sem);
1191 
1192 	if (!usblp->used)
1193 		usblp_cleanup (usblp);
1194 	mutex_unlock (&usblp_mutex);
1195 }
1196 
1197 static int usblp_suspend (struct usb_interface *intf, pm_message_t message)
1198 {
1199 	struct usblp *usblp = usb_get_intfdata (intf);
1200 
1201 	/* this races against normal access and open */
1202 	mutex_lock (&usblp_mutex);
1203 	down (&usblp->sem);
1204 	/* we take no more IO */
1205 	usblp->sleeping = 1;
1206 	usblp_unlink_urbs(usblp);
1207 	up (&usblp->sem);
1208 	mutex_unlock (&usblp_mutex);
1209 
1210 	return 0;
1211 }
1212 
1213 static int usblp_resume (struct usb_interface *intf)
1214 {
1215 	struct usblp *usblp = usb_get_intfdata (intf);
1216 	int r;
1217 
1218 	mutex_lock (&usblp_mutex);
1219 	down (&usblp->sem);
1220 
1221 	usblp->sleeping = 0;
1222 	r = handle_bidir (usblp);
1223 
1224 	up (&usblp->sem);
1225 	mutex_unlock (&usblp_mutex);
1226 
1227 	return r;
1228 }
1229 
1230 static struct usb_device_id usblp_ids [] = {
1231 	{ USB_DEVICE_INFO(7, 1, 1) },
1232 	{ USB_DEVICE_INFO(7, 1, 2) },
1233 	{ USB_DEVICE_INFO(7, 1, 3) },
1234 	{ USB_INTERFACE_INFO(7, 1, 1) },
1235 	{ USB_INTERFACE_INFO(7, 1, 2) },
1236 	{ USB_INTERFACE_INFO(7, 1, 3) },
1237 	{ }						/* Terminating entry */
1238 };
1239 
1240 MODULE_DEVICE_TABLE (usb, usblp_ids);
1241 
1242 static struct usb_driver usblp_driver = {
1243 	.name =		"usblp",
1244 	.probe =	usblp_probe,
1245 	.disconnect =	usblp_disconnect,
1246 	.suspend =	usblp_suspend,
1247 	.resume =	usblp_resume,
1248 	.id_table =	usblp_ids,
1249 };
1250 
1251 static int __init usblp_init(void)
1252 {
1253 	int retval;
1254 	retval = usb_register(&usblp_driver);
1255 	if (!retval)
1256 		info(DRIVER_VERSION ": " DRIVER_DESC);
1257 
1258 	return retval;
1259 }
1260 
1261 static void __exit usblp_exit(void)
1262 {
1263 	usb_deregister(&usblp_driver);
1264 }
1265 
1266 module_init(usblp_init);
1267 module_exit(usblp_exit);
1268 
1269 MODULE_AUTHOR( DRIVER_AUTHOR );
1270 MODULE_DESCRIPTION( DRIVER_DESC );
1271 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1272 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1273 MODULE_LICENSE("GPL");
1274