xref: /linux/drivers/usb/class/usblp.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
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		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
158 							/* first 2 bytes are (big-endian) length */
159 };
160 
161 #ifdef DEBUG
162 static void usblp_dump(struct usblp *usblp) {
163 	int p;
164 
165 	dbg("usblp=0x%p", usblp);
166 	dbg("dev=0x%p", usblp->dev);
167 	dbg("present=%d", usblp->present);
168 	dbg("readbuf=0x%p", usblp->readbuf);
169 	dbg("writebuf=0x%p", usblp->writebuf);
170 	dbg("readurb=0x%p", usblp->readurb);
171 	dbg("writeurb=0x%p", usblp->writeurb);
172 	dbg("readcount=%d", usblp->readcount);
173 	dbg("ifnum=%d", usblp->ifnum);
174     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
175 	dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
176 	dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
177 	dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
178     }
179 	dbg("current_protocol=%d", usblp->current_protocol);
180 	dbg("minor=%d", usblp->minor);
181 	dbg("wcomplete=%d", usblp->wcomplete);
182 	dbg("rcomplete=%d", usblp->rcomplete);
183 	dbg("quirks=%d", usblp->quirks);
184 	dbg("used=%d", usblp->used);
185 	dbg("bidir=%d", usblp->bidir);
186 	dbg("device_id_string=\"%s\"",
187 		usblp->device_id_string ?
188 			usblp->device_id_string + 2 :
189 			(unsigned char *)"(null)");
190 }
191 #endif
192 
193 /* Quirks: various printer quirks are handled by this table & its flags. */
194 
195 struct quirk_printer_struct {
196 	__u16 vendorId;
197 	__u16 productId;
198 	unsigned int quirks;
199 };
200 
201 #define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
202 #define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */
203 
204 static const struct quirk_printer_struct quirk_printers[] = {
205 	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
206 	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
207 	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
208 	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
209 	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
210 	{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
211 	{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
212 	{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
213 	{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
214 	{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
215 	{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
216 	{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
217 	{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
218 	{ 0, 0 }
219 };
220 
221 static int usblp_select_alts(struct usblp *usblp);
222 static int usblp_set_protocol(struct usblp *usblp, int protocol);
223 static int usblp_cache_device_id_string(struct usblp *usblp);
224 
225 /* forward reference to make our lives easier */
226 static struct usb_driver usblp_driver;
227 static DEFINE_MUTEX(usblp_mutex);	/* locks the existence of usblp's */
228 
229 /*
230  * Functions for usblp control messages.
231  */
232 
233 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
234 {
235 	int retval;
236 	int index = usblp->ifnum;
237 
238 	/* High byte has the interface index.
239 	   Low byte has the alternate setting.
240 	 */
241 	if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
242 	  index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
243 	}
244 
245 	retval = usb_control_msg(usblp->dev,
246 		dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
247 		request, type | dir | recip, value, index, buf, len, USBLP_WRITE_TIMEOUT);
248 	dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
249 		request, !!dir, recip, value, index, len, retval);
250 	return retval < 0 ? retval : 0;
251 }
252 
253 #define usblp_read_status(usblp, status)\
254 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
255 #define usblp_get_id(usblp, config, id, maxlen)\
256 	usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
257 #define usblp_reset(usblp)\
258 	usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
259 
260 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
261 	usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
262 
263 /*
264  * See the description for usblp_select_alts() below for the usage
265  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
266  * case of any trouble.
267  */
268 static int proto_bias = -1;
269 
270 /*
271  * URB callback.
272  */
273 
274 static void usblp_bulk_read(struct urb *urb, struct pt_regs *regs)
275 {
276 	struct usblp *usblp = urb->context;
277 
278 	if (unlikely(!usblp || !usblp->dev || !usblp->used))
279 		return;
280 
281 	if (unlikely(!usblp->present))
282 		goto unplug;
283 	if (unlikely(urb->status))
284 		warn("usblp%d: nonzero read/write bulk status received: %d",
285 			usblp->minor, urb->status);
286 	usblp->rcomplete = 1;
287 unplug:
288 	wake_up_interruptible(&usblp->wait);
289 }
290 
291 static void usblp_bulk_write(struct urb *urb, struct pt_regs *regs)
292 {
293 	struct usblp *usblp = urb->context;
294 
295 	if (unlikely(!usblp || !usblp->dev || !usblp->used))
296 		return;
297 	if (unlikely(!usblp->present))
298 		goto unplug;
299 	if (unlikely(urb->status))
300 		warn("usblp%d: nonzero read/write bulk status received: %d",
301 			usblp->minor, urb->status);
302 	usblp->wcomplete = 1;
303 unplug:
304 	wake_up_interruptible(&usblp->wait);
305 }
306 
307 /*
308  * Get and print printer errors.
309  */
310 
311 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
312 
313 static int usblp_check_status(struct usblp *usblp, int err)
314 {
315 	unsigned char status, newerr = 0;
316 	int error;
317 
318 	error = usblp_read_status (usblp, usblp->statusbuf);
319 	if (error < 0) {
320 		if (printk_ratelimit())
321 			err("usblp%d: error %d reading printer status",
322 				usblp->minor, error);
323 		return 0;
324 	}
325 
326 	status = *usblp->statusbuf;
327 
328 	if (~status & LP_PERRORP)
329 		newerr = 3;
330 	if (status & LP_POUTPA)
331 		newerr = 1;
332 	if (~status & LP_PSELECD)
333 		newerr = 2;
334 
335 	if (newerr != err)
336 		info("usblp%d: %s", usblp->minor, usblp_messages[newerr]);
337 
338 	return newerr;
339 }
340 
341 /*
342  * File op functions.
343  */
344 
345 static int usblp_open(struct inode *inode, struct file *file)
346 {
347 	int minor = iminor(inode);
348 	struct usblp *usblp;
349 	struct usb_interface *intf;
350 	int retval;
351 
352 	if (minor < 0)
353 		return -ENODEV;
354 
355 	mutex_lock (&usblp_mutex);
356 
357 	retval = -ENODEV;
358 	intf = usb_find_interface(&usblp_driver, minor);
359 	if (!intf) {
360 		goto out;
361 	}
362 	usblp = usb_get_intfdata (intf);
363 	if (!usblp || !usblp->dev || !usblp->present)
364 		goto out;
365 
366 	retval = -EBUSY;
367 	if (usblp->used)
368 		goto out;
369 
370 	/*
371 	 * TODO: need to implement LP_ABORTOPEN + O_NONBLOCK as in drivers/char/lp.c ???
372 	 * This is #if 0-ed because we *don't* want to fail an open
373 	 * just because the printer is off-line.
374 	 */
375 #if 0
376 	if ((retval = usblp_check_status(usblp, 0))) {
377 		retval = retval > 1 ? -EIO : -ENOSPC;
378 		goto out;
379 	}
380 #else
381 	retval = 0;
382 #endif
383 
384 	usblp->used = 1;
385 	file->private_data = usblp;
386 
387 	usblp->writeurb->transfer_buffer_length = 0;
388 	usblp->wcomplete = 1; /* we begin writeable */
389 	usblp->rcomplete = 0;
390 	usblp->writeurb->status = 0;
391 	usblp->readurb->status = 0;
392 
393 	if (usblp->bidir) {
394 		usblp->readcount = 0;
395 		usblp->readurb->dev = usblp->dev;
396 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0) {
397 			retval = -EIO;
398 			usblp->used = 0;
399 			file->private_data = NULL;
400 		}
401 	}
402 out:
403 	mutex_unlock (&usblp_mutex);
404 	return retval;
405 }
406 
407 static void usblp_cleanup (struct usblp *usblp)
408 {
409 	info("usblp%d: removed", usblp->minor);
410 
411 	kfree (usblp->device_id_string);
412 	kfree (usblp->statusbuf);
413 	usb_free_urb(usblp->writeurb);
414 	usb_free_urb(usblp->readurb);
415 	kfree (usblp);
416 }
417 
418 static void usblp_unlink_urbs(struct usblp *usblp)
419 {
420 	usb_kill_urb(usblp->writeurb);
421 	if (usblp->bidir)
422 		usb_kill_urb(usblp->readurb);
423 }
424 
425 static int usblp_release(struct inode *inode, struct file *file)
426 {
427 	struct usblp *usblp = file->private_data;
428 
429 	mutex_lock (&usblp_mutex);
430 	usblp->used = 0;
431 	if (usblp->present) {
432 		usblp_unlink_urbs(usblp);
433 	} else 		/* finish cleanup from disconnect */
434 		usblp_cleanup (usblp);
435 	mutex_unlock (&usblp_mutex);
436 	return 0;
437 }
438 
439 /* No kernel lock - fine */
440 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
441 {
442 	struct usblp *usblp = file->private_data;
443 	poll_wait(file, &usblp->wait, wait);
444  	return ((!usblp->bidir || !usblp->rcomplete) ? 0 : POLLIN  | POLLRDNORM)
445  			       | (!usblp->wcomplete ? 0 : POLLOUT | POLLWRNORM);
446 }
447 
448 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
449 {
450 	struct usblp *usblp = file->private_data;
451 	int length, err, i;
452 	unsigned char newChannel;
453 	int status;
454 	int twoints[2];
455 	int retval = 0;
456 
457 	down (&usblp->sem);
458 	if (!usblp->present) {
459 		retval = -ENODEV;
460 		goto done;
461 	}
462 
463 	dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
464 		_IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
465 
466 	if (_IOC_TYPE(cmd) == 'P')	/* new-style ioctl number */
467 
468 		switch (_IOC_NR(cmd)) {
469 
470 			case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
471 				if (_IOC_DIR(cmd) != _IOC_READ) {
472 					retval = -EINVAL;
473 					goto done;
474 				}
475 
476 				length = usblp_cache_device_id_string(usblp);
477 				if (length < 0) {
478 					retval = length;
479 					goto done;
480 				}
481 				if (length > _IOC_SIZE(cmd))
482 					length = _IOC_SIZE(cmd); /* truncate */
483 
484 				if (copy_to_user((void __user *) arg,
485 						usblp->device_id_string,
486 						(unsigned long) length)) {
487 					retval = -EFAULT;
488 					goto done;
489 				}
490 
491 				break;
492 
493 			case IOCNR_GET_PROTOCOLS:
494 				if (_IOC_DIR(cmd) != _IOC_READ ||
495 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
496 					retval = -EINVAL;
497 					goto done;
498 				}
499 
500 				twoints[0] = usblp->current_protocol;
501 				twoints[1] = 0;
502 				for (i = USBLP_FIRST_PROTOCOL;
503 				     i <= USBLP_LAST_PROTOCOL; i++) {
504 					if (usblp->protocol[i].alt_setting >= 0)
505 						twoints[1] |= (1<<i);
506 				}
507 
508 				if (copy_to_user((void __user *)arg,
509 						(unsigned char *)twoints,
510 						sizeof(twoints))) {
511 					retval = -EFAULT;
512 					goto done;
513 				}
514 
515 				break;
516 
517 			case IOCNR_SET_PROTOCOL:
518 				if (_IOC_DIR(cmd) != _IOC_WRITE) {
519 					retval = -EINVAL;
520 					goto done;
521 				}
522 
523 #ifdef DEBUG
524 				if (arg == -10) {
525 					usblp_dump(usblp);
526 					break;
527 				}
528 #endif
529 
530 				usblp_unlink_urbs(usblp);
531 				retval = usblp_set_protocol(usblp, arg);
532 				if (retval < 0) {
533 					usblp_set_protocol(usblp,
534 						usblp->current_protocol);
535 				}
536 				break;
537 
538 			case IOCNR_HP_SET_CHANNEL:
539 				if (_IOC_DIR(cmd) != _IOC_WRITE ||
540 				    le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
541 				    usblp->quirks & USBLP_QUIRK_BIDIR) {
542 					retval = -EINVAL;
543 					goto done;
544 				}
545 
546 				err = usblp_hp_channel_change_request(usblp,
547 					arg, &newChannel);
548 				if (err < 0) {
549 					err("usblp%d: error = %d setting "
550 						"HP channel",
551 						usblp->minor, err);
552 					retval = -EIO;
553 					goto done;
554 				}
555 
556 				dbg("usblp%d requested/got HP channel %ld/%d",
557 					usblp->minor, arg, newChannel);
558 				break;
559 
560 			case IOCNR_GET_BUS_ADDRESS:
561 				if (_IOC_DIR(cmd) != _IOC_READ ||
562 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
563 					retval = -EINVAL;
564 					goto done;
565 				}
566 
567 				twoints[0] = usblp->dev->bus->busnum;
568 				twoints[1] = usblp->dev->devnum;
569 				if (copy_to_user((void __user *)arg,
570 						(unsigned char *)twoints,
571 						sizeof(twoints))) {
572 					retval = -EFAULT;
573 					goto done;
574 				}
575 
576 				dbg("usblp%d is bus=%d, device=%d",
577 					usblp->minor, twoints[0], twoints[1]);
578 				break;
579 
580 			case IOCNR_GET_VID_PID:
581 				if (_IOC_DIR(cmd) != _IOC_READ ||
582 				    _IOC_SIZE(cmd) < sizeof(twoints)) {
583 					retval = -EINVAL;
584 					goto done;
585 				}
586 
587 				twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
588 				twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
589 				if (copy_to_user((void __user *)arg,
590 						(unsigned char *)twoints,
591 						sizeof(twoints))) {
592 					retval = -EFAULT;
593 					goto done;
594 				}
595 
596 				dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
597 					usblp->minor, twoints[0], twoints[1]);
598 				break;
599 
600 			case IOCNR_SOFT_RESET:
601 				if (_IOC_DIR(cmd) != _IOC_NONE) {
602 					retval = -EINVAL;
603 					goto done;
604 				}
605 				retval = usblp_reset(usblp);
606 				break;
607 			default:
608 				retval = -ENOTTY;
609 		}
610 	else	/* old-style ioctl value */
611 		switch (cmd) {
612 
613 			case LPGETSTATUS:
614 				if (usblp_read_status(usblp, usblp->statusbuf)) {
615 					if (printk_ratelimit())
616 						err("usblp%d: failed reading printer status",
617 							usblp->minor);
618 					retval = -EIO;
619 					goto done;
620 				}
621 				status = *usblp->statusbuf;
622 				if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
623 					retval = -EFAULT;
624 				break;
625 
626 			default:
627 				retval = -ENOTTY;
628 		}
629 
630 done:
631 	up (&usblp->sem);
632 	return retval;
633 }
634 
635 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
636 {
637 	struct usblp *usblp = file->private_data;
638 	int timeout, rv, err = 0, transfer_length = 0;
639 	size_t writecount = 0;
640 
641 	while (writecount < count) {
642 		if (!usblp->wcomplete) {
643 			barrier();
644 			if (file->f_flags & O_NONBLOCK) {
645 				writecount += transfer_length;
646 				return writecount ? writecount : -EAGAIN;
647 			}
648 
649 			timeout = USBLP_WRITE_TIMEOUT;
650 
651 			rv = wait_event_interruptible_timeout(usblp->wait, usblp->wcomplete || !usblp->present , timeout);
652 			if (rv < 0)
653 				return writecount ? writecount : -EINTR;
654 		}
655 		down (&usblp->sem);
656 		if (!usblp->present) {
657 			up (&usblp->sem);
658 			return -ENODEV;
659 		}
660 
661 		if (usblp->writeurb->status != 0) {
662 			if (usblp->quirks & USBLP_QUIRK_BIDIR) {
663 				if (!usblp->wcomplete)
664 					err("usblp%d: error %d writing to printer",
665 						usblp->minor, usblp->writeurb->status);
666 				err = usblp->writeurb->status;
667 			} else
668 				err = usblp_check_status(usblp, err);
669 			up (&usblp->sem);
670 
671 			/* if the fault was due to disconnect, let khubd's
672 			 * call to usblp_disconnect() grab usblp->sem ...
673 			 */
674 			schedule ();
675 			continue;
676 		}
677 
678 		/* We must increment writecount here, and not at the
679 		 * end of the loop. Otherwise, the final loop iteration may
680 		 * be skipped, leading to incomplete printer output.
681 		 */
682 		writecount += transfer_length;
683 		if (writecount == count) {
684 			up(&usblp->sem);
685 			break;
686 		}
687 
688 		transfer_length=(count - writecount);
689 		if (transfer_length > USBLP_BUF_SIZE)
690 			transfer_length = USBLP_BUF_SIZE;
691 
692 		usblp->writeurb->transfer_buffer_length = transfer_length;
693 
694 		if (copy_from_user(usblp->writeurb->transfer_buffer,
695 				   buffer + writecount, transfer_length)) {
696 			up(&usblp->sem);
697 			return writecount ? writecount : -EFAULT;
698 		}
699 
700 		usblp->writeurb->dev = usblp->dev;
701 		usblp->wcomplete = 0;
702 		err = usb_submit_urb(usblp->writeurb, GFP_KERNEL);
703 		if (err) {
704 			if (err != -ENOMEM)
705 				count = -EIO;
706 			else
707 				count = writecount ? writecount : -ENOMEM;
708 			up (&usblp->sem);
709 			break;
710 		}
711 		up (&usblp->sem);
712 	}
713 
714 	return count;
715 }
716 
717 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
718 {
719 	struct usblp *usblp = file->private_data;
720 	int rv;
721 
722 	if (!usblp->bidir)
723 		return -EINVAL;
724 
725 	down (&usblp->sem);
726 	if (!usblp->present) {
727 		count = -ENODEV;
728 		goto done;
729 	}
730 
731 	if (!usblp->rcomplete) {
732 		barrier();
733 
734 		if (file->f_flags & O_NONBLOCK) {
735 			count = -EAGAIN;
736 			goto done;
737 		}
738 		up(&usblp->sem);
739 		rv = wait_event_interruptible(usblp->wait, usblp->rcomplete || !usblp->present);
740 		down(&usblp->sem);
741 		if (rv < 0) {
742 			count = -EINTR;
743 			goto done;
744 		}
745 	}
746 
747 	if (!usblp->present) {
748 		count = -ENODEV;
749 		goto done;
750 	}
751 
752 	if (usblp->readurb->status) {
753 		err("usblp%d: error %d reading from printer",
754 			usblp->minor, usblp->readurb->status);
755 		usblp->readurb->dev = usblp->dev;
756  		usblp->readcount = 0;
757 		usblp->rcomplete = 0;
758 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0)
759 			dbg("error submitting urb");
760 		count = -EIO;
761 		goto done;
762 	}
763 
764 	count = count < usblp->readurb->actual_length - usblp->readcount ?
765 		count :	usblp->readurb->actual_length - usblp->readcount;
766 
767 	if (copy_to_user(buffer, usblp->readurb->transfer_buffer + usblp->readcount, count)) {
768 		count = -EFAULT;
769 		goto done;
770 	}
771 
772 	if ((usblp->readcount += count) == usblp->readurb->actual_length) {
773 		usblp->readcount = 0;
774 		usblp->readurb->dev = usblp->dev;
775 		usblp->rcomplete = 0;
776 		if (usb_submit_urb(usblp->readurb, GFP_KERNEL)) {
777 			count = -EIO;
778 			goto done;
779 		}
780 	}
781 
782 done:
783 	up (&usblp->sem);
784 	return count;
785 }
786 
787 /*
788  * Checks for printers that have quirks, such as requiring unidirectional
789  * communication but reporting bidirectional; currently some HP printers
790  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
791  * sent at each open (like some Epsons).
792  * Returns 1 if found, 0 if not found.
793  *
794  * HP recommended that we use the bidirectional interface but
795  * don't attempt any bulk IN transfers from the IN endpoint.
796  * Here's some more detail on the problem:
797  * The problem is not that it isn't bidirectional though. The problem
798  * is that if you request a device ID, or status information, while
799  * the buffers are full, the return data will end up in the print data
800  * buffer. For example if you make sure you never request the device ID
801  * while you are sending print data, and you don't try to query the
802  * printer status every couple of milliseconds, you will probably be OK.
803  */
804 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
805 {
806 	int i;
807 
808 	for (i = 0; quirk_printers[i].vendorId; i++) {
809 		if (vendor == quirk_printers[i].vendorId &&
810 		    product == quirk_printers[i].productId)
811 			return quirk_printers[i].quirks;
812  	}
813 	return 0;
814 }
815 
816 static struct file_operations usblp_fops = {
817 	.owner =	THIS_MODULE,
818 	.read =		usblp_read,
819 	.write =	usblp_write,
820 	.poll =		usblp_poll,
821 	.unlocked_ioctl =	usblp_ioctl,
822 	.compat_ioctl =		usblp_ioctl,
823 	.open =		usblp_open,
824 	.release =	usblp_release,
825 };
826 
827 static struct usb_class_driver usblp_class = {
828 	.name =		"lp%d",
829 	.fops =		&usblp_fops,
830 	.minor_base =	USBLP_MINOR_BASE,
831 };
832 
833 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
834 {
835 	struct usb_interface *intf = to_usb_interface(dev);
836 	struct usblp *usblp = usb_get_intfdata (intf);
837 
838 	if (usblp->device_id_string[0] == 0 &&
839 	    usblp->device_id_string[1] == 0)
840 		return 0;
841 
842 	return sprintf(buf, "%s", usblp->device_id_string+2);
843 }
844 
845 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
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 = kzalloc(sizeof(struct usblp), GFP_KERNEL))) {
858 		err("out of memory for usblp");
859 		goto abort;
860 	}
861 	usblp->dev = dev;
862 	init_MUTEX (&usblp->sem);
863 	init_waitqueue_head(&usblp->wait);
864 	usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
865 	usblp->intf = intf;
866 
867 	usblp->writeurb = usb_alloc_urb(0, GFP_KERNEL);
868 	if (!usblp->writeurb) {
869 		err("out of memory");
870 		goto abort;
871 	}
872 	usblp->readurb = usb_alloc_urb(0, GFP_KERNEL);
873 	if (!usblp->readurb) {
874 		err("out of memory");
875 		goto abort;
876 	}
877 
878 	/* Malloc device ID string buffer to the largest expected length,
879 	 * since we can re-query it on an ioctl and a dynamic string
880 	 * could change in length. */
881 	if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
882 		err("out of memory for device_id_string");
883 		goto abort;
884 	}
885 
886 	usblp->writebuf = usblp->readbuf = NULL;
887 	usblp->writeurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
888 	usblp->readurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
889 	/* Malloc write & read buffers.  We somewhat wastefully
890 	 * malloc both regardless of bidirectionality, because the
891 	 * alternate setting can be changed later via an ioctl. */
892 	if (!(usblp->writebuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
893 				GFP_KERNEL, &usblp->writeurb->transfer_dma))) {
894 		err("out of memory for write buf");
895 		goto abort;
896 	}
897 	if (!(usblp->readbuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
898 				GFP_KERNEL, &usblp->readurb->transfer_dma))) {
899 		err("out of memory for read buf");
900 		goto abort;
901 	}
902 
903 	/* Allocate buffer for printer status */
904 	usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
905 	if (!usblp->statusbuf) {
906 		err("out of memory for statusbuf");
907 		goto abort;
908 	}
909 
910 	/* Lookup quirks for this printer. */
911 	usblp->quirks = usblp_quirks(
912 		le16_to_cpu(dev->descriptor.idVendor),
913 		le16_to_cpu(dev->descriptor.idProduct));
914 
915 	/* Analyze and pick initial alternate settings and endpoints. */
916 	protocol = usblp_select_alts(usblp);
917 	if (protocol < 0) {
918 		dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
919 			le16_to_cpu(dev->descriptor.idVendor),
920 			le16_to_cpu(dev->descriptor.idProduct));
921 		goto abort;
922 	}
923 
924 	/* Setup the selected alternate setting and endpoints. */
925 	if (usblp_set_protocol(usblp, protocol) < 0)
926 		goto abort;
927 
928 	/* Retrieve and store the device ID string. */
929 	usblp_cache_device_id_string(usblp);
930 	device_create_file(&intf->dev, &dev_attr_ieee1284_id);
931 
932 #ifdef DEBUG
933 	usblp_check_status(usblp, 0);
934 #endif
935 
936 	usb_set_intfdata (intf, usblp);
937 
938 	usblp->present = 1;
939 
940 	retval = usb_register_dev(intf, &usblp_class);
941 	if (retval) {
942 		err("Not able to get a minor for this device.");
943 		goto abort_intfdata;
944 	}
945 	usblp->minor = intf->minor;
946 	info("usblp%d: USB %sdirectional printer dev %d "
947 		"if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X",
948 		usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
949 		usblp->ifnum,
950 		usblp->protocol[usblp->current_protocol].alt_setting,
951 		usblp->current_protocol,
952 		le16_to_cpu(usblp->dev->descriptor.idVendor),
953 		le16_to_cpu(usblp->dev->descriptor.idProduct));
954 
955 	return 0;
956 
957 abort_intfdata:
958 	usb_set_intfdata (intf, NULL);
959 	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
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 	device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1155 
1156 	mutex_lock (&usblp_mutex);
1157 	down (&usblp->sem);
1158 	usblp->present = 0;
1159 	usb_set_intfdata (intf, NULL);
1160 
1161 	usblp_unlink_urbs(usblp);
1162 	usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1163 			usblp->writebuf, usblp->writeurb->transfer_dma);
1164 	usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1165 			usblp->readbuf, usblp->readurb->transfer_dma);
1166 	up (&usblp->sem);
1167 
1168 	if (!usblp->used)
1169 		usblp_cleanup (usblp);
1170 	mutex_unlock (&usblp_mutex);
1171 }
1172 
1173 static struct usb_device_id usblp_ids [] = {
1174 	{ USB_DEVICE_INFO(7, 1, 1) },
1175 	{ USB_DEVICE_INFO(7, 1, 2) },
1176 	{ USB_DEVICE_INFO(7, 1, 3) },
1177 	{ USB_INTERFACE_INFO(7, 1, 1) },
1178 	{ USB_INTERFACE_INFO(7, 1, 2) },
1179 	{ USB_INTERFACE_INFO(7, 1, 3) },
1180 	{ }						/* Terminating entry */
1181 };
1182 
1183 MODULE_DEVICE_TABLE (usb, usblp_ids);
1184 
1185 static struct usb_driver usblp_driver = {
1186 	.name =		"usblp",
1187 	.probe =	usblp_probe,
1188 	.disconnect =	usblp_disconnect,
1189 	.id_table =	usblp_ids,
1190 };
1191 
1192 static int __init usblp_init(void)
1193 {
1194 	int retval;
1195 	retval = usb_register(&usblp_driver);
1196 	if (!retval)
1197 		info(DRIVER_VERSION ": " DRIVER_DESC);
1198 
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