xref: /openbmc/linux/drivers/usb/class/usblp.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
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	<rddunlap@osdl.org>
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  *
11  * USB Printer Device Class driver for USB printers and printer cables
12  *
13  * Sponsored by SuSE
14  *
15  * ChangeLog:
16  *	v0.1 - thorough cleaning, URBification, almost a rewrite
17  *	v0.2 - some more cleanups
18  *	v0.3 - cleaner again, waitqueue fixes
19  *	v0.4 - fixes in unidirectional mode
20  *	v0.5 - add DEVICE_ID string support
21  *	v0.6 - never time out
22  *	v0.7 - fixed bulk-IN read and poll (David Paschal)
23  *	v0.8 - add devfs support
24  *	v0.9 - fix unplug-while-open paths
25  *	v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
26  *	v0.11 - add proto_bias option (Pete Zaitcev)
27  *	v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
28  *	v0.13 - alloc space for statusbuf (<status> not on stack);
29  *		use usb_buffer_alloc() for read buf & write buf;
30  */
31 
32 /*
33  * This program is free software; you can redistribute it and/or modify
34  * it under the terms of the GNU General Public License as published by
35  * the Free Software Foundation; either version 2 of the License, or
36  * (at your option) any later version.
37  *
38  * This program is distributed in the hope that it will be useful,
39  * but WITHOUT ANY WARRANTY; without even the implied warranty of
40  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
41  * GNU General Public License for more details.
42  *
43  * You should have received a copy of the GNU General Public License
44  * along with this program; if not, write to the Free Software
45  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
46  */
47 
48 #include <linux/module.h>
49 #include <linux/kernel.h>
50 #include <linux/sched.h>
51 #include <linux/smp_lock.h>
52 #include <linux/signal.h>
53 #include <linux/poll.h>
54 #include <linux/init.h>
55 #include <linux/slab.h>
56 #include <linux/lp.h>
57 #undef DEBUG
58 #include <linux/usb.h>
59 
60 /*
61  * Version Information
62  */
63 #define DRIVER_VERSION "v0.13"
64 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
65 #define DRIVER_DESC "USB Printer Device Class driver"
66 
67 #define USBLP_BUF_SIZE		8192
68 #define USBLP_DEVICE_ID_SIZE	1024
69 
70 /* ioctls: */
71 #define LPGETSTATUS		0x060b		/* same as in drivers/char/lp.c */
72 #define IOCNR_GET_DEVICE_ID		1
73 #define IOCNR_GET_PROTOCOLS		2
74 #define IOCNR_SET_PROTOCOL		3
75 #define IOCNR_HP_SET_CHANNEL		4
76 #define IOCNR_GET_BUS_ADDRESS		5
77 #define IOCNR_GET_VID_PID		6
78 #define IOCNR_SOFT_RESET		7
79 /* Get device_id string: */
80 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
81 /* The following ioctls were added for http://hpoj.sourceforge.net: */
82 /* Get two-int array:
83  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
84  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
85 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
86 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
87 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
88 /* Set channel number (HP Vendor-specific command): */
89 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
90 /* Get two-int array: [0]=bus number, [1]=device address: */
91 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
92 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
93 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
94 /* Perform class specific soft reset */
95 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
96 
97 /*
98  * A DEVICE_ID string may include the printer's serial number.
99  * It should end with a semi-colon (';').
100  * An example from an HP 970C DeskJet printer is (this is one long string,
101  * with the serial number changed):
102 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:                    ;
103  */
104 
105 /*
106  * USB Printer Requests
107  */
108 
109 #define USBLP_REQ_GET_ID			0x00
110 #define USBLP_REQ_GET_STATUS			0x01
111 #define USBLP_REQ_RESET				0x02
112 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST	0x00	/* HP Vendor-specific */
113 
114 #define USBLP_MINORS		16
115 #define USBLP_MINOR_BASE	0
116 
117 #define USBLP_WRITE_TIMEOUT	(5000)			/* 5 seconds */
118 
119 #define USBLP_FIRST_PROTOCOL	1
120 #define USBLP_LAST_PROTOCOL	3
121 #define USBLP_MAX_PROTOCOLS	(USBLP_LAST_PROTOCOL+1)
122 
123 /*
124  * some arbitrary status buffer size;
125  * need a status buffer that is allocated via kmalloc(), not on stack
126  */
127 #define STATUS_BUF_SIZE		8
128 
129 struct usblp {
130 	struct usb_device 	*dev;			/* USB device */
131 	struct semaphore	sem;			/* locks this struct, especially "dev" */
132 	char			*writebuf;		/* write transfer_buffer */
133 	char			*readbuf;		/* read transfer_buffer */
134 	char			*statusbuf;		/* status transfer_buffer */
135 	struct urb		*readurb, *writeurb;	/* The urbs */
136 	wait_queue_head_t	wait;			/* Zzzzz ... */
137 	int			readcount;		/* Counter for reads */
138 	int			ifnum;			/* Interface number */
139 	struct usb_interface	*intf;			/* The interface */
140 	/* Alternate-setting numbers and endpoints for each protocol
141 	 * (7/1/{index=1,2,3}) that the device supports: */
142 	struct {
143 		int				alt_setting;
144 		struct usb_endpoint_descriptor	*epwrite;
145 		struct usb_endpoint_descriptor	*epread;
146 	}			protocol[USBLP_MAX_PROTOCOLS];
147 	int			current_protocol;
148 	int			minor;			/* minor number of device */
149 	int			wcomplete;		/* writing is completed */
150 	int			rcomplete;		/* reading is completed */
151 	unsigned int		quirks;			/* quirks flags */
152 	unsigned char		used;			/* True if open */
153 	unsigned char		present;		/* True if not disconnected */
154 	unsigned char		bidir;			/* interface is bidirectional */
155 	unsigned char		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
156 							/* first 2 bytes are (big-endian) length */
157 };
158 
159 #ifdef DEBUG
160 static void usblp_dump(struct usblp *usblp) {
161 	int p;
162 
163 	dbg("usblp=0x%p", usblp);
164 	dbg("dev=0x%p", usblp->dev);
165 	dbg("present=%d", usblp->present);
166 	dbg("readbuf=0x%p", usblp->readbuf);
167 	dbg("writebuf=0x%p", usblp->writebuf);
168 	dbg("readurb=0x%p", usblp->readurb);
169 	dbg("writeurb=0x%p", usblp->writeurb);
170 	dbg("readcount=%d", usblp->readcount);
171 	dbg("ifnum=%d", usblp->ifnum);
172     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
173 	dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
174 	dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
175 	dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
176     }
177 	dbg("current_protocol=%d", usblp->current_protocol);
178 	dbg("minor=%d", usblp->minor);
179 	dbg("wcomplete=%d", usblp->wcomplete);
180 	dbg("rcomplete=%d", usblp->rcomplete);
181 	dbg("quirks=%d", usblp->quirks);
182 	dbg("used=%d", usblp->used);
183 	dbg("bidir=%d", usblp->bidir);
184 	dbg("device_id_string=\"%s\"",
185 		usblp->device_id_string ?
186 			usblp->device_id_string + 2 :
187 			(unsigned char *)"(null)");
188 }
189 #endif
190 
191 /* Quirks: various printer quirks are handled by this table & its flags. */
192 
193 struct quirk_printer_struct {
194 	__u16 vendorId;
195 	__u16 productId;
196 	unsigned int quirks;
197 };
198 
199 #define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
200 #define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */
201 
202 static struct quirk_printer_struct quirk_printers[] = {
203 	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
204 	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
205 	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
206 	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
207 	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
208 	{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
209 	{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
210 	{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
211 	{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
212 	{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
213 	{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
214 	{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
215 	{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
216 	{ 0, 0 }
217 };
218 
219 static int usblp_select_alts(struct usblp *usblp);
220 static int usblp_set_protocol(struct usblp *usblp, int protocol);
221 static int usblp_cache_device_id_string(struct usblp *usblp);
222 
223 /* forward reference to make our lives easier */
224 static struct usb_driver usblp_driver;
225 static DECLARE_MUTEX(usblp_sem);	/* locks the existence of usblp's */
226 
227 /*
228  * Functions for usblp control messages.
229  */
230 
231 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
232 {
233 	int retval;
234 	int index = usblp->ifnum;
235 
236 	/* High byte has the interface index.
237 	   Low byte has the alternate setting.
238 	 */
239 	if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
240 	  index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
241 	}
242 
243 	retval = usb_control_msg(usblp->dev,
244 		dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
245 		request, type | dir | recip, value, index, buf, len, USBLP_WRITE_TIMEOUT);
246 	dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
247 		request, !!dir, recip, value, index, len, retval);
248 	return retval < 0 ? retval : 0;
249 }
250 
251 #define usblp_read_status(usblp, status)\
252 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
253 #define usblp_get_id(usblp, config, id, maxlen)\
254 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
255 #define usblp_reset(usblp)\
256 	usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
257 
258 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
259 	usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
260 
261 /*
262  * See the description for usblp_select_alts() below for the usage
263  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
264  * case of any trouble.
265  */
266 static int proto_bias = -1;
267 
268 /*
269  * URB callback.
270  */
271 
272 static void usblp_bulk_read(struct urb *urb, struct pt_regs *regs)
273 {
274 	struct usblp *usblp = urb->context;
275 
276 	if (!usblp || !usblp->dev || !usblp->used || !usblp->present)
277 		return;
278 
279 	if (unlikely(urb->status))
280 		warn("usblp%d: nonzero read/write bulk status received: %d",
281 			usblp->minor, urb->status);
282 	usblp->rcomplete = 1;
283 	wake_up_interruptible(&usblp->wait);
284 }
285 
286 static void usblp_bulk_write(struct urb *urb, struct pt_regs *regs)
287 {
288 	struct usblp *usblp = urb->context;
289 
290 	if (!usblp || !usblp->dev || !usblp->used || !usblp->present)
291 		return;
292 
293 	if (unlikely(urb->status))
294 		warn("usblp%d: nonzero read/write bulk status received: %d",
295 			usblp->minor, urb->status);
296 	usblp->wcomplete = 1;
297 	wake_up_interruptible(&usblp->wait);
298 }
299 
300 /*
301  * Get and print printer errors.
302  */
303 
304 static char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
305 
306 static int usblp_check_status(struct usblp *usblp, int err)
307 {
308 	unsigned char status, newerr = 0;
309 	int error;
310 
311 	error = usblp_read_status (usblp, usblp->statusbuf);
312 	if (error < 0) {
313 		err("usblp%d: error %d reading printer status",
314 			usblp->minor, error);
315 		return 0;
316 	}
317 
318 	status = *usblp->statusbuf;
319 
320 	if (~status & LP_PERRORP)
321 		newerr = 3;
322 	if (status & LP_POUTPA)
323 		newerr = 1;
324 	if (~status & LP_PSELECD)
325 		newerr = 2;
326 
327 	if (newerr != err)
328 		info("usblp%d: %s", usblp->minor, usblp_messages[newerr]);
329 
330 	return newerr;
331 }
332 
333 /*
334  * File op functions.
335  */
336 
337 static int usblp_open(struct inode *inode, struct file *file)
338 {
339 	int minor = iminor(inode);
340 	struct usblp *usblp;
341 	struct usb_interface *intf;
342 	int retval;
343 
344 	if (minor < 0)
345 		return -ENODEV;
346 
347 	down (&usblp_sem);
348 
349 	retval = -ENODEV;
350 	intf = usb_find_interface(&usblp_driver, minor);
351 	if (!intf) {
352 		goto out;
353 	}
354 	usblp = usb_get_intfdata (intf);
355 	if (!usblp || !usblp->dev || !usblp->present)
356 		goto out;
357 
358 	retval = -EBUSY;
359 	if (usblp->used)
360 		goto out;
361 
362 	/*
363 	 * TODO: need to implement LP_ABORTOPEN + O_NONBLOCK as in drivers/char/lp.c ???
364 	 * This is #if 0-ed because we *don't* want to fail an open
365 	 * just because the printer is off-line.
366 	 */
367 #if 0
368 	if ((retval = usblp_check_status(usblp, 0))) {
369 		retval = retval > 1 ? -EIO : -ENOSPC;
370 		goto out;
371 	}
372 #else
373 	retval = 0;
374 #endif
375 
376 	usblp->used = 1;
377 	file->private_data = usblp;
378 
379 	usblp->writeurb->transfer_buffer_length = 0;
380 	usblp->wcomplete = 1; /* we begin writeable */
381 	usblp->rcomplete = 0;
382 
383 	if (usblp->bidir) {
384 		usblp->readcount = 0;
385 		usblp->readurb->dev = usblp->dev;
386 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0) {
387 			retval = -EIO;
388 			usblp->used = 0;
389 			file->private_data = NULL;
390 		}
391 	}
392 out:
393 	up (&usblp_sem);
394 	return retval;
395 }
396 
397 static void usblp_cleanup (struct usblp *usblp)
398 {
399 	info("usblp%d: removed", usblp->minor);
400 
401 	kfree (usblp->device_id_string);
402 	kfree (usblp->statusbuf);
403 	usb_free_urb(usblp->writeurb);
404 	usb_free_urb(usblp->readurb);
405 	kfree (usblp);
406 }
407 
408 static void usblp_unlink_urbs(struct usblp *usblp)
409 {
410 	usb_kill_urb(usblp->writeurb);
411 	if (usblp->bidir)
412 		usb_kill_urb(usblp->readurb);
413 }
414 
415 static int usblp_release(struct inode *inode, struct file *file)
416 {
417 	struct usblp *usblp = file->private_data;
418 
419 	down (&usblp_sem);
420 	usblp->used = 0;
421 	if (usblp->present) {
422 		usblp_unlink_urbs(usblp);
423 	} else 		/* finish cleanup from disconnect */
424 		usblp_cleanup (usblp);
425 	up (&usblp_sem);
426 	return 0;
427 }
428 
429 /* No kernel lock - fine */
430 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
431 {
432 	struct usblp *usblp = file->private_data;
433 	poll_wait(file, &usblp->wait, wait);
434  	return ((!usblp->bidir || !usblp->rcomplete) ? 0 : POLLIN  | POLLRDNORM)
435  			       | (!usblp->wcomplete ? 0 : POLLOUT | POLLWRNORM);
436 }
437 
438 static int usblp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
439 {
440 	struct usblp *usblp = file->private_data;
441 	int length, err, i;
442 	unsigned char newChannel;
443 	int status;
444 	int twoints[2];
445 	int retval = 0;
446 
447 	down (&usblp->sem);
448 	if (!usblp->present) {
449 		retval = -ENODEV;
450 		goto done;
451 	}
452 
453 	dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
454 		_IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
455 
456 	if (_IOC_TYPE(cmd) == 'P')	/* new-style ioctl number */
457 
458 		switch (_IOC_NR(cmd)) {
459 
460 			case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
461 				if (_IOC_DIR(cmd) != _IOC_READ) {
462 					retval = -EINVAL;
463 					goto done;
464 				}
465 
466 				length = usblp_cache_device_id_string(usblp);
467 				if (length < 0) {
468 					retval = length;
469 					goto done;
470 				}
471 				if (length > _IOC_SIZE(cmd))
472 					length = _IOC_SIZE(cmd); /* truncate */
473 
474 				if (copy_to_user((void __user *) arg,
475 						usblp->device_id_string,
476 						(unsigned long) length)) {
477 					retval = -EFAULT;
478 					goto done;
479 				}
480 
481 				break;
482 
483 			case IOCNR_GET_PROTOCOLS:
484 				if (_IOC_DIR(cmd) != _IOC_READ ||
485 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
486 					retval = -EINVAL;
487 					goto done;
488 				}
489 
490 				twoints[0] = usblp->current_protocol;
491 				twoints[1] = 0;
492 				for (i = USBLP_FIRST_PROTOCOL;
493 				     i <= USBLP_LAST_PROTOCOL; i++) {
494 					if (usblp->protocol[i].alt_setting >= 0)
495 						twoints[1] |= (1<<i);
496 				}
497 
498 				if (copy_to_user((void __user *)arg,
499 						(unsigned char *)twoints,
500 						sizeof(twoints))) {
501 					retval = -EFAULT;
502 					goto done;
503 				}
504 
505 				break;
506 
507 			case IOCNR_SET_PROTOCOL:
508 				if (_IOC_DIR(cmd) != _IOC_WRITE) {
509 					retval = -EINVAL;
510 					goto done;
511 				}
512 
513 #ifdef DEBUG
514 				if (arg == -10) {
515 					usblp_dump(usblp);
516 					break;
517 				}
518 #endif
519 
520 				usblp_unlink_urbs(usblp);
521 				retval = usblp_set_protocol(usblp, arg);
522 				if (retval < 0) {
523 					usblp_set_protocol(usblp,
524 						usblp->current_protocol);
525 				}
526 				break;
527 
528 			case IOCNR_HP_SET_CHANNEL:
529 				if (_IOC_DIR(cmd) != _IOC_WRITE ||
530 				    le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
531 				    usblp->quirks & USBLP_QUIRK_BIDIR) {
532 					retval = -EINVAL;
533 					goto done;
534 				}
535 
536 				err = usblp_hp_channel_change_request(usblp,
537 					arg, &newChannel);
538 				if (err < 0) {
539 					err("usblp%d: error = %d setting "
540 						"HP channel",
541 						usblp->minor, err);
542 					retval = -EIO;
543 					goto done;
544 				}
545 
546 				dbg("usblp%d requested/got HP channel %ld/%d",
547 					usblp->minor, arg, newChannel);
548 				break;
549 
550 			case IOCNR_GET_BUS_ADDRESS:
551 				if (_IOC_DIR(cmd) != _IOC_READ ||
552 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
553 					retval = -EINVAL;
554 					goto done;
555 				}
556 
557 				twoints[0] = usblp->dev->bus->busnum;
558 				twoints[1] = usblp->dev->devnum;
559 				if (copy_to_user((void __user *)arg,
560 						(unsigned char *)twoints,
561 						sizeof(twoints))) {
562 					retval = -EFAULT;
563 					goto done;
564 				}
565 
566 				dbg("usblp%d is bus=%d, device=%d",
567 					usblp->minor, twoints[0], twoints[1]);
568 				break;
569 
570 			case IOCNR_GET_VID_PID:
571 				if (_IOC_DIR(cmd) != _IOC_READ ||
572 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
573 					retval = -EINVAL;
574 					goto done;
575 				}
576 
577 				twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
578 				twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
579 				if (copy_to_user((void __user *)arg,
580 						(unsigned char *)twoints,
581 						sizeof(twoints))) {
582 					retval = -EFAULT;
583 					goto done;
584 				}
585 
586 				dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
587 					usblp->minor, twoints[0], twoints[1]);
588 				break;
589 
590 			case IOCNR_SOFT_RESET:
591 				if (_IOC_DIR(cmd) != _IOC_NONE) {
592 					retval = -EINVAL;
593 					goto done;
594 				}
595 				retval = usblp_reset(usblp);
596 				break;
597 			default:
598 				retval = -ENOTTY;
599 		}
600 	else	/* old-style ioctl value */
601 		switch (cmd) {
602 
603 			case LPGETSTATUS:
604 				if (usblp_read_status(usblp, usblp->statusbuf)) {
605 					err("usblp%d: failed reading printer status", usblp->minor);
606 					retval = -EIO;
607 					goto done;
608 				}
609 				status = *usblp->statusbuf;
610 				if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
611 					retval = -EFAULT;
612 				break;
613 
614 			default:
615 				retval = -ENOTTY;
616 		}
617 
618 done:
619 	up (&usblp->sem);
620 	return retval;
621 }
622 
623 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
624 {
625 	DECLARE_WAITQUEUE(wait, current);
626 	struct usblp *usblp = file->private_data;
627 	int timeout, err = 0, transfer_length = 0;
628 	size_t writecount = 0;
629 
630 	while (writecount < count) {
631 		if (!usblp->wcomplete) {
632 			barrier();
633 			if (file->f_flags & O_NONBLOCK) {
634 				writecount += transfer_length;
635 				return writecount ? writecount : -EAGAIN;
636 			}
637 
638 			timeout = USBLP_WRITE_TIMEOUT;
639 			add_wait_queue(&usblp->wait, &wait);
640 			while ( 1==1 ) {
641 
642 				if (signal_pending(current)) {
643 					remove_wait_queue(&usblp->wait, &wait);
644 					return writecount ? writecount : -EINTR;
645 				}
646 				set_current_state(TASK_INTERRUPTIBLE);
647 				if (timeout && !usblp->wcomplete) {
648 					timeout = schedule_timeout(timeout);
649 				} else {
650 					set_current_state(TASK_RUNNING);
651 					break;
652 				}
653 			}
654 			remove_wait_queue(&usblp->wait, &wait);
655 		}
656 
657 		down (&usblp->sem);
658 		if (!usblp->present) {
659 			up (&usblp->sem);
660 			return -ENODEV;
661 		}
662 
663 		if (usblp->writeurb->status != 0) {
664 			if (usblp->quirks & USBLP_QUIRK_BIDIR) {
665 				if (!usblp->wcomplete)
666 					err("usblp%d: error %d writing to printer",
667 						usblp->minor, usblp->writeurb->status);
668 				err = usblp->writeurb->status;
669 			} else
670 				err = usblp_check_status(usblp, err);
671 			up (&usblp->sem);
672 
673 			/* if the fault was due to disconnect, let khubd's
674 			 * call to usblp_disconnect() grab usblp->sem ...
675 			 */
676 			schedule ();
677 			continue;
678 		}
679 
680 		/* We must increment writecount here, and not at the
681 		 * end of the loop. Otherwise, the final loop iteration may
682 		 * be skipped, leading to incomplete printer output.
683 		 */
684 		writecount += transfer_length;
685 		if (writecount == count) {
686 			up(&usblp->sem);
687 			break;
688 		}
689 
690 		transfer_length=(count - writecount);
691 		if (transfer_length > USBLP_BUF_SIZE)
692 			transfer_length = USBLP_BUF_SIZE;
693 
694 		usblp->writeurb->transfer_buffer_length = transfer_length;
695 
696 		if (copy_from_user(usblp->writeurb->transfer_buffer,
697 				   buffer + writecount, transfer_length)) {
698 			up(&usblp->sem);
699 			return writecount ? writecount : -EFAULT;
700 		}
701 
702 		usblp->writeurb->dev = usblp->dev;
703 		usblp->wcomplete = 0;
704 		err = usb_submit_urb(usblp->writeurb, GFP_KERNEL);
705 		if (err) {
706 			if (err != -ENOMEM)
707 				count = -EIO;
708 			else
709 				count = writecount ? writecount : -ENOMEM;
710 			up (&usblp->sem);
711 			break;
712 		}
713 		up (&usblp->sem);
714 	}
715 
716 	return count;
717 }
718 
719 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
720 {
721 	struct usblp *usblp = file->private_data;
722 	DECLARE_WAITQUEUE(wait, current);
723 
724 	if (!usblp->bidir)
725 		return -EINVAL;
726 
727 	down (&usblp->sem);
728 	if (!usblp->present) {
729 		count = -ENODEV;
730 		goto done;
731 	}
732 
733 	if (!usblp->rcomplete) {
734 		barrier();
735 
736 		if (file->f_flags & O_NONBLOCK) {
737 			count = -EAGAIN;
738 			goto done;
739 		}
740 
741 		add_wait_queue(&usblp->wait, &wait);
742 		while (1==1) {
743 			if (signal_pending(current)) {
744 				count = -EINTR;
745 				remove_wait_queue(&usblp->wait, &wait);
746 				goto done;
747 			}
748 			up (&usblp->sem);
749 			set_current_state(TASK_INTERRUPTIBLE);
750 			if (!usblp->rcomplete) {
751 				schedule();
752 			} else {
753 				set_current_state(TASK_RUNNING);
754 				break;
755 			}
756 			down (&usblp->sem);
757 		}
758 		remove_wait_queue(&usblp->wait, &wait);
759 	}
760 
761 	if (!usblp->present) {
762 		count = -ENODEV;
763 		goto done;
764 	}
765 
766 	if (usblp->readurb->status) {
767 		err("usblp%d: error %d reading from printer",
768 			usblp->minor, usblp->readurb->status);
769 		usblp->readurb->dev = usblp->dev;
770  		usblp->readcount = 0;
771 		usblp->rcomplete = 0;
772 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0)
773 			dbg("error submitting urb");
774 		count = -EIO;
775 		goto done;
776 	}
777 
778 	count = count < usblp->readurb->actual_length - usblp->readcount ?
779 		count :	usblp->readurb->actual_length - usblp->readcount;
780 
781 	if (copy_to_user(buffer, usblp->readurb->transfer_buffer + usblp->readcount, count)) {
782 		count = -EFAULT;
783 		goto done;
784 	}
785 
786 	if ((usblp->readcount += count) == usblp->readurb->actual_length) {
787 		usblp->readcount = 0;
788 		usblp->readurb->dev = usblp->dev;
789 		usblp->rcomplete = 0;
790 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL)) {
791 			count = -EIO;
792 			goto done;
793 		}
794 	}
795 
796 done:
797 	up (&usblp->sem);
798 	return count;
799 }
800 
801 /*
802  * Checks for printers that have quirks, such as requiring unidirectional
803  * communication but reporting bidirectional; currently some HP printers
804  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
805  * sent at each open (like some Epsons).
806  * Returns 1 if found, 0 if not found.
807  *
808  * HP recommended that we use the bidirectional interface but
809  * don't attempt any bulk IN transfers from the IN endpoint.
810  * Here's some more detail on the problem:
811  * The problem is not that it isn't bidirectional though. The problem
812  * is that if you request a device ID, or status information, while
813  * the buffers are full, the return data will end up in the print data
814  * buffer. For example if you make sure you never request the device ID
815  * while you are sending print data, and you don't try to query the
816  * printer status every couple of milliseconds, you will probably be OK.
817  */
818 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
819 {
820 	int i;
821 
822 	for (i = 0; quirk_printers[i].vendorId; i++) {
823 		if (vendor == quirk_printers[i].vendorId &&
824 		    product == quirk_printers[i].productId)
825 			return quirk_printers[i].quirks;
826  	}
827 	return 0;
828 }
829 
830 static struct file_operations usblp_fops = {
831 	.owner =	THIS_MODULE,
832 	.read =		usblp_read,
833 	.write =	usblp_write,
834 	.poll =		usblp_poll,
835 	.ioctl =	usblp_ioctl,
836 	.open =		usblp_open,
837 	.release =	usblp_release,
838 };
839 
840 static struct usb_class_driver usblp_class = {
841 	.name =		"usb/lp%d",
842 	.fops =		&usblp_fops,
843 	.mode =		S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP,
844 	.minor_base =	USBLP_MINOR_BASE,
845 };
846 
847 static int usblp_probe(struct usb_interface *intf,
848 		       const struct usb_device_id *id)
849 {
850 	struct usb_device *dev = interface_to_usbdev (intf);
851 	struct usblp *usblp = NULL;
852 	int protocol;
853 	int retval;
854 
855 	/* Malloc and start initializing usblp structure so we can use it
856 	 * directly. */
857 	if (!(usblp = kmalloc(sizeof(struct usblp), GFP_KERNEL))) {
858 		err("out of memory for usblp");
859 		goto abort;
860 	}
861 	memset(usblp, 0, sizeof(struct usblp));
862 	usblp->dev = dev;
863 	init_MUTEX (&usblp->sem);
864 	init_waitqueue_head(&usblp->wait);
865 	usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
866 	usblp->intf = intf;
867 
868 	usblp->writeurb = usb_alloc_urb(0, GFP_KERNEL);
869 	if (!usblp->writeurb) {
870 		err("out of memory");
871 		goto abort;
872 	}
873 	usblp->readurb = usb_alloc_urb(0, GFP_KERNEL);
874 	if (!usblp->readurb) {
875 		err("out of memory");
876 		goto abort;
877 	}
878 
879 	/* Malloc device ID string buffer to the largest expected length,
880 	 * since we can re-query it on an ioctl and a dynamic string
881 	 * could change in length. */
882 	if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
883 		err("out of memory for device_id_string");
884 		goto abort;
885 	}
886 
887 	usblp->writebuf = usblp->readbuf = NULL;
888 	usblp->writeurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
889 	usblp->readurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
890 	/* Malloc write & read buffers.  We somewhat wastefully
891 	 * malloc both regardless of bidirectionality, because the
892 	 * alternate setting can be changed later via an ioctl. */
893 	if (!(usblp->writebuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
894 				GFP_KERNEL, &usblp->writeurb->transfer_dma))) {
895 		err("out of memory for write buf");
896 		goto abort;
897 	}
898 	if (!(usblp->readbuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
899 				GFP_KERNEL, &usblp->readurb->transfer_dma))) {
900 		err("out of memory for read buf");
901 		goto abort;
902 	}
903 
904 	/* Allocate buffer for printer status */
905 	usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
906 	if (!usblp->statusbuf) {
907 		err("out of memory for statusbuf");
908 		goto abort;
909 	}
910 
911 	/* Lookup quirks for this printer. */
912 	usblp->quirks = usblp_quirks(
913 		le16_to_cpu(dev->descriptor.idVendor),
914 		le16_to_cpu(dev->descriptor.idProduct));
915 
916 	/* Analyze and pick initial alternate settings and endpoints. */
917 	protocol = usblp_select_alts(usblp);
918 	if (protocol < 0) {
919 		dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
920 			le16_to_cpu(dev->descriptor.idVendor),
921 			le16_to_cpu(dev->descriptor.idProduct));
922 		goto abort;
923 	}
924 
925 	/* Setup the selected alternate setting and endpoints. */
926 	if (usblp_set_protocol(usblp, protocol) < 0)
927 		goto abort;
928 
929 	/* Retrieve and store the device ID string. */
930 	usblp_cache_device_id_string(usblp);
931 
932 #ifdef DEBUG
933 	usblp_check_status(usblp, 0);
934 #endif
935 
936 	info("usblp%d: USB %sdirectional printer dev %d "
937 		"if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X",
938 		usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
939 		usblp->ifnum,
940 		usblp->protocol[usblp->current_protocol].alt_setting,
941 		usblp->current_protocol,
942 		le16_to_cpu(usblp->dev->descriptor.idVendor),
943 		le16_to_cpu(usblp->dev->descriptor.idProduct));
944 
945 	usb_set_intfdata (intf, usblp);
946 
947 	usblp->present = 1;
948 
949 	retval = usb_register_dev(intf, &usblp_class);
950 	if (retval) {
951 		err("Not able to get a minor for this device.");
952 		goto abort_intfdata;
953 	}
954 	usblp->minor = intf->minor;
955 
956 	return 0;
957 
958 abort_intfdata:
959 	usb_set_intfdata (intf, NULL);
960 abort:
961 	if (usblp) {
962 		if (usblp->writebuf)
963 			usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
964 				usblp->writebuf, usblp->writeurb->transfer_dma);
965 		if (usblp->readbuf)
966 			usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
967 				usblp->readbuf, usblp->writeurb->transfer_dma);
968 		kfree(usblp->statusbuf);
969 		kfree(usblp->device_id_string);
970 		usb_free_urb(usblp->writeurb);
971 		usb_free_urb(usblp->readurb);
972 		kfree(usblp);
973 	}
974 	return -EIO;
975 }
976 
977 /*
978  * We are a "new" style driver with usb_device_id table,
979  * but our requirements are too intricate for simple match to handle.
980  *
981  * The "proto_bias" option may be used to specify the preferred protocol
982  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
983  * supports the preferred protocol, then we bind to it.
984  *
985  * The best interface for us is 7/1/2, because it is compatible
986  * with a stream of characters. If we find it, we bind to it.
987  *
988  * Note that the people from hpoj.sourceforge.net need to be able to
989  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
990  *
991  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
992  * stream-compatible, because this matches the behaviour of the old code.
993  *
994  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
995  */
996 static int usblp_select_alts(struct usblp *usblp)
997 {
998 	struct usb_interface *if_alt;
999 	struct usb_host_interface *ifd;
1000 	struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1001 	int p, i, e;
1002 
1003 	if_alt = usblp->intf;
1004 
1005 	for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1006 		usblp->protocol[p].alt_setting = -1;
1007 
1008 	/* Find out what we have. */
1009 	for (i = 0; i < if_alt->num_altsetting; i++) {
1010 		ifd = &if_alt->altsetting[i];
1011 
1012 		if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1013 			continue;
1014 
1015 		if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1016 		    ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1017 			continue;
1018 
1019 		/* Look for bulk OUT and IN endpoints. */
1020 		epwrite = epread = NULL;
1021 		for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1022 			epd = &ifd->endpoint[e].desc;
1023 
1024 			if ((epd->bmAttributes&USB_ENDPOINT_XFERTYPE_MASK)!=
1025 			    USB_ENDPOINT_XFER_BULK)
1026 				continue;
1027 
1028 			if (!(epd->bEndpointAddress & USB_ENDPOINT_DIR_MASK)) {
1029 				if (!epwrite)
1030 					epwrite = epd;
1031 
1032 			} else {
1033 				if (!epread)
1034 					epread = epd;
1035 			}
1036 		}
1037 
1038 		/* Ignore buggy hardware without the right endpoints. */
1039 		if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1040 			continue;
1041 
1042 		/* Turn off reads for 7/1/1 (unidirectional) interfaces
1043 		 * and buggy bidirectional printers. */
1044 		if (ifd->desc.bInterfaceProtocol == 1) {
1045 			epread = NULL;
1046 		} else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1047 			info("Disabling reads from problem bidirectional "
1048 				"printer on usblp%d", usblp->minor);
1049 			epread = NULL;
1050 		}
1051 
1052 		usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1053 				ifd->desc.bAlternateSetting;
1054 		usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1055 		usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1056 	}
1057 
1058 	/* If our requested protocol is supported, then use it. */
1059 	if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1060 	    proto_bias <= USBLP_LAST_PROTOCOL &&
1061 	    usblp->protocol[proto_bias].alt_setting != -1)
1062 		return proto_bias;
1063 
1064 	/* Ordering is important here. */
1065 	if (usblp->protocol[2].alt_setting != -1)
1066 		return 2;
1067 	if (usblp->protocol[1].alt_setting != -1)
1068 		return 1;
1069 	if (usblp->protocol[3].alt_setting != -1)
1070 		return 3;
1071 
1072 	/* If nothing is available, then don't bind to this device. */
1073 	return -1;
1074 }
1075 
1076 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1077 {
1078 	int r, alts;
1079 
1080 	if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1081 		return -EINVAL;
1082 
1083 	alts = usblp->protocol[protocol].alt_setting;
1084 	if (alts < 0)
1085 		return -EINVAL;
1086 	r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1087 	if (r < 0) {
1088 		err("can't set desired altsetting %d on interface %d",
1089 			alts, usblp->ifnum);
1090 		return r;
1091 	}
1092 
1093 	usb_fill_bulk_urb(usblp->writeurb, usblp->dev,
1094 		usb_sndbulkpipe(usblp->dev,
1095 		  usblp->protocol[protocol].epwrite->bEndpointAddress),
1096 		usblp->writebuf, 0,
1097 		usblp_bulk_write, usblp);
1098 
1099 	usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1100 	if (usblp->bidir)
1101 		usb_fill_bulk_urb(usblp->readurb, usblp->dev,
1102 			usb_rcvbulkpipe(usblp->dev,
1103 			  usblp->protocol[protocol].epread->bEndpointAddress),
1104 			usblp->readbuf, USBLP_BUF_SIZE,
1105 			usblp_bulk_read, usblp);
1106 
1107 	usblp->current_protocol = protocol;
1108 	dbg("usblp%d set protocol %d", usblp->minor, protocol);
1109 	return 0;
1110 }
1111 
1112 /* Retrieves and caches device ID string.
1113  * Returns length, including length bytes but not null terminator.
1114  * On error, returns a negative errno value. */
1115 static int usblp_cache_device_id_string(struct usblp *usblp)
1116 {
1117 	int err, length;
1118 
1119 	err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1120 	if (err < 0) {
1121 		dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1122 			usblp->minor, err);
1123 		usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1124 		return -EIO;
1125 	}
1126 
1127 	/* First two bytes are length in big-endian.
1128 	 * They count themselves, and we copy them into
1129 	 * the user's buffer. */
1130 	length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1131 	if (length < 2)
1132 		length = 2;
1133 	else if (length >= USBLP_DEVICE_ID_SIZE)
1134 		length = USBLP_DEVICE_ID_SIZE - 1;
1135 	usblp->device_id_string[length] = '\0';
1136 
1137 	dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1138 		usblp->minor, length, &usblp->device_id_string[2]);
1139 
1140 	return length;
1141 }
1142 
1143 static void usblp_disconnect(struct usb_interface *intf)
1144 {
1145 	struct usblp *usblp = usb_get_intfdata (intf);
1146 
1147 	usb_deregister_dev(intf, &usblp_class);
1148 
1149 	if (!usblp || !usblp->dev) {
1150 		err("bogus disconnect");
1151 		BUG ();
1152 	}
1153 
1154 	down (&usblp_sem);
1155 	down (&usblp->sem);
1156 	usblp->present = 0;
1157 	usb_set_intfdata (intf, NULL);
1158 
1159 	usblp_unlink_urbs(usblp);
1160 	usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1161 			usblp->writebuf, usblp->writeurb->transfer_dma);
1162 	usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1163 			usblp->readbuf, usblp->readurb->transfer_dma);
1164 	up (&usblp->sem);
1165 
1166 	if (!usblp->used)
1167 		usblp_cleanup (usblp);
1168 	up (&usblp_sem);
1169 }
1170 
1171 static struct usb_device_id usblp_ids [] = {
1172 	{ USB_DEVICE_INFO(7, 1, 1) },
1173 	{ USB_DEVICE_INFO(7, 1, 2) },
1174 	{ USB_DEVICE_INFO(7, 1, 3) },
1175 	{ USB_INTERFACE_INFO(7, 1, 1) },
1176 	{ USB_INTERFACE_INFO(7, 1, 2) },
1177 	{ USB_INTERFACE_INFO(7, 1, 3) },
1178 	{ }						/* Terminating entry */
1179 };
1180 
1181 MODULE_DEVICE_TABLE (usb, usblp_ids);
1182 
1183 static struct usb_driver usblp_driver = {
1184 	.owner =	THIS_MODULE,
1185 	.name =		"usblp",
1186 	.probe =	usblp_probe,
1187 	.disconnect =	usblp_disconnect,
1188 	.id_table =	usblp_ids,
1189 };
1190 
1191 static int __init usblp_init(void)
1192 {
1193 	int retval;
1194 	retval = usb_register(&usblp_driver);
1195 	if (retval)
1196 		goto out;
1197 	info(DRIVER_VERSION ": " DRIVER_DESC);
1198 out:
1199 	return retval;
1200 }
1201 
1202 static void __exit usblp_exit(void)
1203 {
1204 	usb_deregister(&usblp_driver);
1205 }
1206 
1207 module_init(usblp_init);
1208 module_exit(usblp_exit);
1209 
1210 MODULE_AUTHOR( DRIVER_AUTHOR );
1211 MODULE_DESCRIPTION( DRIVER_DESC );
1212 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1213 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1214 MODULE_LICENSE("GPL");
1215