File: /usr/src/linux/drivers/usb/printer.c

1     /*
2      * printer.c  Version 0.8
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	<randy.dunlap@intel.com>
7      * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
8      *
9      * USB Printer Device Class driver for USB printers and printer cables
10      *
11      * Sponsored by SuSE
12      *
13      * ChangeLog:
14      *	v0.1 - thorough cleaning, URBification, almost a rewrite
15      *	v0.2 - some more cleanups
16      *	v0.3 - cleaner again, waitqueue fixes
17      *	v0.4 - fixes in unidirectional mode
18      *	v0.5 - add DEVICE_ID string support
19      *	v0.6 - never time out
20      *	v0.7 - fixed bulk-IN read and poll (David Paschal, paschal@rcsis.com)
21      *	v0.8 - add devfs support
22      *	v0.9 - fix unplug-while-open paths
23      */
24     
25     /*
26      * This program is free software; you can redistribute it and/or modify
27      * it under the terms of the GNU General Public License as published by
28      * the Free Software Foundation; either version 2 of the License, or
29      * (at your option) any later version.
30      *
31      * This program is distributed in the hope that it will be useful,
32      * but WITHOUT ANY WARRANTY; without even the implied warranty of
33      * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
34      * GNU General Public License for more details.
35      *
36      * You should have received a copy of the GNU General Public License
37      * along with this program; if not, write to the Free Software
38      * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
39      */
40     
41     #include <linux/module.h>
42     #include <linux/kernel.h>
43     #include <linux/sched.h>
44     #include <linux/smp_lock.h>
45     #include <linux/signal.h>
46     #include <linux/poll.h>
47     #include <linux/init.h>
48     #include <linux/slab.h>
49     #include <linux/lp.h>
50     #include <linux/devfs_fs_kernel.h>
51     #undef DEBUG
52     #include <linux/usb.h>
53     
54     /*
55      * Version Information
56      */
57     #define DRIVER_VERSION "v0.8"
58     #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap"
59     #define DRIVER_DESC "USB Printer Device Class driver"
60     
61     #define USBLP_BUF_SIZE		8192
62     #define DEVICE_ID_SIZE		1024
63     
64     #define IOCNR_GET_DEVICE_ID	1
65     #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)	/* get device_id string */
66     #define LPGETSTATUS		0x060b		/* same as in drivers/char/lp.c */
67     
68     /*
69      * A DEVICE_ID string may include the printer's serial number.
70      * It should end with a semi-colon (';').
71      * An example from an HP 970C DeskJet printer is (this is one long string,
72      * with the serial number changed):
73     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:                    ;
74      */
75     
76     /*
77      * USB Printer Requests
78      */
79     
80     #define USBLP_REQ_GET_ID	0x00
81     #define USBLP_REQ_GET_STATUS	0x01
82     #define USBLP_REQ_RESET		0x02
83     
84     #define USBLP_MINORS		16
85     #define USBLP_MINOR_BASE	0
86     
87     #define USBLP_WRITE_TIMEOUT	(5*HZ)			/* 5 seconds */
88     
89     struct usblp {
90     	struct usb_device 	*dev;			/* USB device */
91     	devfs_handle_t		devfs;			/* devfs device */
92     	struct semaphore	sem;			/* locks this struct, especially "dev" */
93     	struct urb		readurb, writeurb;	/* The urbs */
94     	wait_queue_head_t	wait;			/* Zzzzz ... */
95     	int			readcount;		/* Counter for reads */
96     	int			ifnum;			/* Interface number */
97     	int			minor;			/* minor number of device */
98     	unsigned int		quirks;			/* quirks flags */
99     	unsigned char		used;			/* True if open */
100     	unsigned char		bidir;			/* interface is bidirectional */
101     	unsigned char		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
102     							/* first 2 bytes are (big-endian) length */
103     };
104     
105     extern devfs_handle_t usb_devfs_handle;			/* /dev/usb dir. */
106     
107     static struct usblp *usblp_table[USBLP_MINORS];
108     
109     /* Quirks: various printer quirks are handled by this table & its flags. */
110     
111     struct quirk_printer_struct {
112     	__u16 vendorId;
113     	__u16 productId;
114     	unsigned int quirks;
115     };
116     
117     #define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
118     #define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */
119     
120     static struct quirk_printer_struct quirk_printers[] = {
121     	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
122     	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
123     	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
124     	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
125     	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
126     	{ 0, 0 }
127     };
128     
129     /*
130      * Functions for usblp control messages.
131      */
132     
133     static int usblp_ctrl_msg(struct usblp *usblp, int request, int dir, int recip, int value, void *buf, int len)
134     {
135     	int retval = usb_control_msg(usblp->dev,
136     		dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
137     		request, USB_TYPE_CLASS | dir | recip, value, usblp->ifnum, buf, len, HZ * 5);
138     	dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d len: %#x result: %d",
139     		request, !!dir, recip, value, len, retval);
140     	return retval < 0 ? retval : 0;
141     }
142     
143     #define usblp_read_status(usblp, status)\
144     	usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
145     #define usblp_get_id(usblp, config, id, maxlen)\
146     	usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
147     #define usblp_reset(usblp)\
148     	usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
149     
150     /*
151      * URB callback.
152      */
153     
154     static void usblp_bulk(struct urb *urb)
155     {
156     	struct usblp *usblp = urb->context;
157     
158     	if (!usblp || !usblp->dev || !usblp->used)
159     		return;
160     
161     	if (urb->status)
162     		warn("usblp%d: nonzero read/write bulk status received: %d",
163     			usblp->minor, urb->status);
164     
165     	wake_up_interruptible(&usblp->wait);
166     }
167     
168     /*
169      * Get and print printer errors.
170      */
171     
172     static char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
173     
174     static int usblp_check_status(struct usblp *usblp, int err)
175     {
176     	unsigned char status, newerr = 0;
177     	int error;
178     
179     	error = usblp_read_status (usblp, &status);
180     	if (error < 0) {
181     		err("usblp%d: error %d reading printer status",
182     			usblp->minor, error);
183     		return 0;
184     	}
185     
186     	if (~status & LP_PERRORP) {
187     		newerr = 3;
188     		if (status & LP_POUTPA) newerr = 1;
189     		if (~status & LP_PSELECD) newerr = 2;
190     	}
191     
192     	if (newerr != err)
193     		info("usblp%d: %s", usblp->minor, usblp_messages[newerr]);
194     
195     	return newerr;
196     }
197     
198     /*
199      * File op functions.
200      */
201     
202     static int usblp_open(struct inode *inode, struct file *file)
203     {
204     	int minor = MINOR(inode->i_rdev) - USBLP_MINOR_BASE;
205     	struct usblp *usblp;
206     	int retval;
207     
208     	if (minor < 0 || minor >= USBLP_MINORS)
209     		return -ENODEV;
210     
211     	lock_kernel();
212     	usblp  = usblp_table[minor];
213     
214     	retval = -ENODEV;
215     	if (!usblp || !usblp->dev)
216     		goto out;
217     
218     	retval = -EBUSY;
219     	if (usblp->used)
220     		goto out;
221     
222     	/*
223     	 * TODO: need to implement LP_ABORTOPEN + O_NONBLOCK as in drivers/char/lp.c ???
224     	 * This is #if 0-ed because we *don't* want to fail an open
225     	 * just because the printer is off-line.
226     	 */
227     #if 0
228     	if ((retval = usblp_check_status(usblp, 0))) {
229     		retval = retval > 1 ? -EIO : -ENOSPC;
230     		goto out;
231     	}
232     #else
233     	retval = 0;
234     #endif
235     
236     	usblp->used = 1;
237     	file->private_data = usblp;
238     
239     	usblp->writeurb.transfer_buffer_length = 0;
240     	usblp->writeurb.status = 0;
241     
242     	if (usblp->bidir) {
243     		usblp->readcount = 0;
244     		usblp->readurb.dev = usblp->dev;
245     		if (usb_submit_urb(&usblp->readurb) < 0) {
246     			retval = -EIO;
247     			usblp->used = 0;
248     			file->private_data = NULL;
249     		}
250     	}
251     out:
252     	unlock_kernel();
253     	return retval;
254     }
255     
256     static void usblp_cleanup (struct usblp *usblp)
257     {
258     	devfs_unregister (usblp->devfs);
259     	usblp_table [usblp->minor] = NULL;
260     	info ("usblp%d: removed", usblp->minor);
261     
262     	kfree (usblp->writeurb.transfer_buffer);
263     	kfree (usblp->device_id_string);
264     	kfree (usblp);
265     }
266     
267     static int usblp_release(struct inode *inode, struct file *file)
268     {
269     	struct usblp *usblp = file->private_data;
270     
271     	down (&usblp->sem);
272     	lock_kernel();
273     	usblp->used = 0;
274     	if (usblp->dev) {
275     		if (usblp->bidir)
276     			usb_unlink_urb(&usblp->readurb);
277     		usb_unlink_urb(&usblp->writeurb);
278     		up(&usblp->sem);
279     	} else 		/* finish cleanup from disconnect */
280     		usblp_cleanup (usblp);
281     	unlock_kernel();
282     	return 0;
283     }
284     
285     /* No kernel lock - fine */
286     static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
287     {
288     	struct usblp *usblp = file->private_data;
289     	poll_wait(file, &usblp->wait, wait);
290      	return ((!usblp->bidir || usblp->readurb.status  == -EINPROGRESS) ? 0 : POLLIN  | POLLRDNORM)
291      			       | (usblp->writeurb.status == -EINPROGRESS  ? 0 : POLLOUT | POLLWRNORM);
292     }
293     
294     static int usblp_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
295     {
296     	struct usblp *usblp = file->private_data;
297     	int length, err;
298     	unsigned char status;
299     	int retval = 0;
300     
301     	down (&usblp->sem);
302     	if (!usblp->dev) {
303     		retval = -ENODEV;
304     		goto done;
305     	}
306     
307     	if (_IOC_TYPE(cmd) == 'P')	/* new-style ioctl number */
308     
309     		switch (_IOC_NR(cmd)) {
310     
311     			case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
312     				if (_IOC_DIR(cmd) != _IOC_READ) {
313     					retval = -EINVAL;
314     					goto done;
315     				}
316     
317     				err = usblp_get_id(usblp, 0, usblp->device_id_string, DEVICE_ID_SIZE - 1);
318     				if (err < 0) {
319     					dbg ("usblp%d: error = %d reading IEEE-1284 Device ID string",
320     						usblp->minor, err);
321     					usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
322     					retval = -EIO;
323     					goto done;
324     				}
325     
326     				length = (usblp->device_id_string[0] << 8) + usblp->device_id_string[1]; /* big-endian */
327     				if (length < DEVICE_ID_SIZE)
328     					usblp->device_id_string[length] = '\0';
329     				else
330     					usblp->device_id_string[DEVICE_ID_SIZE - 1] = '\0';
331     
332     				dbg ("usblp%d Device ID string [%d/max %d]='%s'",
333     					usblp->minor, length, _IOC_SIZE(cmd), &usblp->device_id_string[2]);
334     
335     				if (length > _IOC_SIZE(cmd)) length = _IOC_SIZE(cmd); /* truncate */
336     
337     				if (copy_to_user((unsigned char *) arg,
338     						usblp->device_id_string, (unsigned long) length)) {
339     					retval = -EFAULT;
340     					goto done;
341     				}
342     
343     				break;
344     
345     			default:
346     				retval = -EINVAL;
347     		}
348     	else	/* old-style ioctl value */
349     		switch (cmd) {
350     
351     			case LPGETSTATUS:
352     				if (usblp_read_status(usblp, &status)) {
353     					err("usblp%d: failed reading printer status", usblp->minor);
354     					retval = -EIO;
355     					goto done;
356     				}
357     				if (copy_to_user ((unsigned char *)arg, &status, 1))
358     					retval = -EFAULT;
359     				break;
360     
361     			default:
362     				retval = -EINVAL;
363     		}
364     
365     done:
366     	up (&usblp->sem);
367     	return retval;
368     }
369     
370     static ssize_t usblp_write(struct file *file, const char *buffer, size_t count, loff_t *ppos)
371     {
372     	struct usblp *usblp = file->private_data;
373     	int timeout, err = 0, writecount = 0;
374     
375     	while (writecount < count) {
376     
377     		// FIXME:  only use urb->status inside completion
378     		// callbacks; this way is racey...
379     		if (usblp->writeurb.status == -EINPROGRESS) {
380     
381     			if (file->f_flags & O_NONBLOCK)
382     				return -EAGAIN;
383     
384     			timeout = USBLP_WRITE_TIMEOUT;
385     			while (timeout && usblp->writeurb.status == -EINPROGRESS) {
386     
387     				if (signal_pending(current))
388     					return writecount ? writecount : -EINTR;
389     
390     				timeout = interruptible_sleep_on_timeout(&usblp->wait, timeout);
391     			}
392     		}
393     
394     		down (&usblp->sem);
395     		if (!usblp->dev) {
396     			up (&usblp->sem);
397     			return -ENODEV;
398     		}
399     
400     		if (usblp->writeurb.status != 0) {
401     			if (usblp->quirks & USBLP_QUIRK_BIDIR) {
402     				if (usblp->writeurb.status != -EINPROGRESS)
403     					err("usblp%d: error %d writing to printer",
404     						usblp->minor, usblp->writeurb.status);
405     				err = usblp->writeurb.status;
406     			} else
407     				err = usblp_check_status(usblp, err);
408     			up (&usblp->sem);
409     
410     			/* if the fault was due to disconnect, let khubd's
411     			 * call to usblp_disconnect() grab usblp->sem ...
412     			 */
413     			schedule ();
414     			continue;
415     		}
416     
417     		writecount += usblp->writeurb.transfer_buffer_length;
418     		usblp->writeurb.transfer_buffer_length = 0;
419     
420     		if (writecount == count) {
421     			up (&usblp->sem);
422     			break;
423     		}
424     
425     		usblp->writeurb.transfer_buffer_length = (count - writecount) < USBLP_BUF_SIZE ?
426     							 (count - writecount) : USBLP_BUF_SIZE;
427     
428     		if (copy_from_user(usblp->writeurb.transfer_buffer, buffer + writecount,
429     				usblp->writeurb.transfer_buffer_length)) return -EFAULT;
430     
431     		usblp->writeurb.dev = usblp->dev;
432     		usb_submit_urb(&usblp->writeurb);
433     		up (&usblp->sem);
434     	}
435     
436     	return count;
437     }
438     
439     static ssize_t usblp_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
440     {
441     	struct usblp *usblp = file->private_data;
442     
443     	if (!usblp->bidir)
444     		return -EINVAL;
445     
446     	down (&usblp->sem);
447     	if (!usblp->dev) {
448     		count = -ENODEV;
449     		goto done;
450     	}
451     
452     	if (usblp->readurb.status == -EINPROGRESS) {
453     
454     		if (file->f_flags & O_NONBLOCK) {
455     			count = -EAGAIN;
456     			goto done;
457     		}
458     
459     		// FIXME:  only use urb->status inside completion
460     		// callbacks; this way is racey...
461     		while (usblp->readurb.status == -EINPROGRESS) {
462     			if (signal_pending(current)) {
463     				count = -EINTR;
464     				goto done;
465     			}
466     			up (&usblp->sem);
467     			interruptible_sleep_on(&usblp->wait);
468     			down (&usblp->sem);
469     		}
470     	}
471     
472     	if (!usblp->dev) {
473     		count = -ENODEV;
474     		goto done;
475     	}
476     
477     	if (usblp->readurb.status) {
478     		err("usblp%d: error %d reading from printer",
479     			usblp->minor, usblp->readurb.status);
480     		usblp->readurb.dev = usblp->dev;
481      		usblp->readcount = 0;
482     		usb_submit_urb(&usblp->readurb);
483     		count = -EIO;
484     		goto done;
485     	}
486     
487     	count = count < usblp->readurb.actual_length - usblp->readcount ?
488     		count :	usblp->readurb.actual_length - usblp->readcount;
489     
490     	if (copy_to_user(buffer, usblp->readurb.transfer_buffer + usblp->readcount, count)) {
491     		count = -EFAULT;
492     		goto done;
493     	}
494     
495     	if ((usblp->readcount += count) == usblp->readurb.actual_length) {
496     		usblp->readcount = 0;
497     		usblp->readurb.dev = usblp->dev;
498     		usb_submit_urb(&usblp->readurb);
499     	}
500     
501     done:
502     	up (&usblp->sem);
503     	return count;
504     }
505     
506     /*
507      * Checks for printers that have quirks, such as requiring unidirectional
508      * communication but reporting bidirectional; currently some HP printers
509      * have this flaw (HP 810, 880, 895, etc.), or needing an init string
510      * sent at each open (like some Epsons).
511      * Returns 1 if found, 0 if not found.
512      *
513      * HP recommended that we use the bidirectional interface but
514      * don't attempt any bulk IN transfers from the IN endpoint.
515      * Here's some more detail on the problem:
516      * The problem is not that it isn't bidirectional though. The problem
517      * is that if you request a device ID, or status information, while
518      * the buffers are full, the return data will end up in the print data
519      * buffer. For example if you make sure you never request the device ID
520      * while you are sending print data, and you don't try to query the
521      * printer status every couple of milliseconds, you will probably be OK.
522      */
523     static unsigned int usblp_quirks (__u16 vendor, __u16 product)
524     {
525     	int i;
526     
527     	for (i = 0; quirk_printers[i].vendorId; i++) {
528     		if (vendor == quirk_printers[i].vendorId &&
529     		    product == quirk_printers[i].productId)
530     			return quirk_printers[i].quirks;
531      	}
532     	return 0;
533     }
534     
535     static struct file_operations usblp_fops = {
536     	owner:		THIS_MODULE,
537     	read:		usblp_read,
538     	write:		usblp_write,
539     	poll:		usblp_poll,
540     	ioctl:		usblp_ioctl,
541     	open:		usblp_open,
542     	release:	usblp_release,
543     };
544     
545     static void *usblp_probe(struct usb_device *dev, unsigned int ifnum,
546     			 const struct usb_device_id *id)
547     {
548     	struct usb_interface_descriptor *interface;
549     	struct usb_endpoint_descriptor *epread, *epwrite;
550     	struct usblp *usblp;
551     	int minor, i, bidir = 0, quirks;
552     	int alts = dev->actconfig->interface[ifnum].act_altsetting;
553     	int length, err;
554     	char *buf;
555     	char name[6];
556     
557     	/* If a bidirectional interface exists, use it. */
558     	for (i = 0; i < dev->actconfig->interface[ifnum].num_altsetting; i++) {
559     
560     		interface = &dev->actconfig->interface[ifnum].altsetting[i];
561     
562     		if (interface->bInterfaceClass != 7 || interface->bInterfaceSubClass != 1 ||
563     		    interface->bInterfaceProtocol < 1 || interface->bInterfaceProtocol > 3 ||
564     		   (interface->bInterfaceProtocol > 1 && interface->bNumEndpoints < 2))
565     			continue;
566     
567     		if (interface->bInterfaceProtocol > 1) {
568     			bidir = 1;
569     			alts = i;
570     			break;
571     		}
572     	}
573     
574     	interface = &dev->actconfig->interface[ifnum].altsetting[alts];
575     	if (usb_set_interface(dev, ifnum, alts))
576     		err("can't set desired altsetting %d on interface %d", alts, ifnum);
577     
578     	epwrite = interface->endpoint + 0;
579     	epread = bidir ? interface->endpoint + 1 : NULL;
580     
581     	if ((epwrite->bEndpointAddress & 0x80) == 0x80) {
582     		if (interface->bNumEndpoints == 1)
583     			return NULL;
584     		epwrite = interface->endpoint + 1;
585     		epread = bidir ? interface->endpoint + 0 : NULL;
586     	}
587     
588     	if ((epwrite->bEndpointAddress & 0x80) == 0x80)
589     		return NULL;
590     
591     	if (bidir && (epread->bEndpointAddress & 0x80) != 0x80)
592     		return NULL;
593     
594     	for (minor = 0; minor < USBLP_MINORS && usblp_table[minor]; minor++);
595     	if (usblp_table[minor]) {
596     		err("no more free usblp devices");
597     		return NULL;
598     	}
599     
600     	if (!(usblp = kmalloc(sizeof(struct usblp), GFP_KERNEL))) {
601     		err("out of memory");
602     		return NULL;
603     	}
604     	memset(usblp, 0, sizeof(struct usblp));
605     	init_MUTEX (&usblp->sem);
606     
607     	/* lookup quirks for this printer */
608     	quirks = usblp_quirks(dev->descriptor.idVendor, dev->descriptor.idProduct);
609     
610     	if (bidir && (quirks & USBLP_QUIRK_BIDIR)) {
611     		bidir = 0;
612     		epread = NULL;
613     		info ("Disabling reads from problem bidirectional printer on usblp%d",
614     			minor);
615     	}
616     
617     	usblp->dev = dev;
618     	usblp->ifnum = ifnum;
619     	usblp->minor = minor;
620     	usblp->bidir = bidir;
621     	usblp->quirks = quirks;
622     
623     	init_waitqueue_head(&usblp->wait);
624     
625     	if (!(buf = kmalloc(USBLP_BUF_SIZE * (bidir ? 2 : 1), GFP_KERNEL))) {
626     		err("out of memory");
627     		kfree(usblp);
628     		return NULL;
629     	}
630     
631     	if (!(usblp->device_id_string = kmalloc(DEVICE_ID_SIZE, GFP_KERNEL))) {
632     		err("out of memory");
633     		kfree(usblp);
634     		kfree(buf);
635     		return NULL;
636     	}
637     
638     	FILL_BULK_URB(&usblp->writeurb, dev, usb_sndbulkpipe(dev, epwrite->bEndpointAddress),
639     		buf, 0, usblp_bulk, usblp);
640     
641     	if (bidir)
642     		FILL_BULK_URB(&usblp->readurb, dev, usb_rcvbulkpipe(dev, epread->bEndpointAddress),
643     			buf + USBLP_BUF_SIZE, USBLP_BUF_SIZE, usblp_bulk, usblp);
644     
645     	/* Get the device_id string if possible. FIXME: Could make this kmalloc(length). */
646     	err = usblp_get_id(usblp, 0, usblp->device_id_string, DEVICE_ID_SIZE - 1);
647     	if (err >= 0) {
648     		length = (usblp->device_id_string[0] << 8) + usblp->device_id_string[1]; /* big-endian */
649     		if (length < DEVICE_ID_SIZE)
650     			usblp->device_id_string[length] = '\0';
651     		else
652     			usblp->device_id_string[DEVICE_ID_SIZE - 1] = '\0';
653     		dbg ("usblp%d Device ID string [%d]=%s",
654     			minor, length, &usblp->device_id_string[2]);
655     	}
656     	else {
657     		err ("usblp%d: error = %d reading IEEE-1284 Device ID string",
658     			minor, err);
659     		usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
660     	}
661     
662     #ifdef DEBUG
663     	usblp_check_status(usblp, 0);
664     #endif
665     
666     	sprintf(name, "lp%d", minor);
667     
668     	/* if we have devfs, create with perms=660 */
669     	usblp->devfs = devfs_register(usb_devfs_handle, name,
670     				      DEVFS_FL_DEFAULT, USB_MAJOR,
671     				      USBLP_MINOR_BASE + minor,
672     				      S_IFCHR | S_IRUSR | S_IWUSR | S_IRGRP |
673     				      S_IWGRP, &usblp_fops, NULL);
674     
675     	info("usblp%d: USB %sdirectional printer dev %d if %d alt %d",
676     		minor, bidir ? "Bi" : "Uni", dev->devnum, ifnum, alts);
677     
678     	return usblp_table[minor] = usblp;
679     }
680     
681     static void usblp_disconnect(struct usb_device *dev, void *ptr)
682     {
683     	struct usblp *usblp = ptr;
684     
685     	if (!usblp || !usblp->dev) {
686     		err("bogus disconnect");
687     		BUG ();
688     	}
689     
690     	down (&usblp->sem);
691     	lock_kernel();
692     	usblp->dev = NULL;
693     
694     	usb_unlink_urb(&usblp->writeurb);
695     	if (usblp->bidir)
696     		usb_unlink_urb(&usblp->readurb);
697     
698     	if (!usblp->used)
699     		usblp_cleanup (usblp);
700     	else 	/* cleanup later, on close */
701     		up (&usblp->sem);
702     	unlock_kernel();
703     }
704     
705     static struct usb_device_id usblp_ids [] = {
706     	{ USB_INTERFACE_INFO(7, 1, 1) },
707     	{ USB_INTERFACE_INFO(7, 1, 2) },
708     	{ USB_INTERFACE_INFO(7, 1, 3) },
709     	{ }						/* Terminating entry */
710     };
711     
712     MODULE_DEVICE_TABLE (usb, usblp_ids);
713     
714     static struct usb_driver usblp_driver = {
715     	name:		"usblp",
716     	probe:		usblp_probe,
717     	disconnect:	usblp_disconnect,
718     	fops:		&usblp_fops,
719     	minor:		USBLP_MINOR_BASE,
720     	id_table:	usblp_ids,
721     };
722     
723     static int __init usblp_init(void)
724     {
725     	if (usb_register(&usblp_driver))
726     		return -1;
727     	info(DRIVER_VERSION ":" DRIVER_DESC);
728     	return 0;
729     }
730     
731     static void __exit usblp_exit(void)
732     {
733     	usb_deregister(&usblp_driver);
734     }
735     
736     module_init(usblp_init);
737     module_exit(usblp_exit);
738     
739     MODULE_AUTHOR( DRIVER_AUTHOR );
740     MODULE_DESCRIPTION( DRIVER_DESC );
741     
742