USB: Push BKL on open down into the drivers
[linux-2.6.git] / drivers / usb / class / usblp.c
1 /*
2  * usblp.c
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  *      none  - Maintained in Linux kernel after v0.13
32  */
33
34 /*
35  * This program is free software; you can redistribute it and/or modify
36  * it under the terms of the GNU General Public License as published by
37  * the Free Software Foundation; either version 2 of the License, or
38  * (at your option) any later version.
39  *
40  * This program is distributed in the hope that it will be useful,
41  * but WITHOUT ANY WARRANTY; without even the implied warranty of
42  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
43  * GNU General Public License for more details.
44  *
45  * You should have received a copy of the GNU General Public License
46  * along with this program; if not, write to the Free Software
47  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
48  */
49
50 #include <linux/module.h>
51 #include <linux/kernel.h>
52 #include <linux/sched.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 #include <linux/smp_lock.h>
60 #undef DEBUG
61 #include <linux/usb.h>
62
63 /*
64  * Version Information
65  */
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_BUF_SIZE_IN       1024
71 #define USBLP_DEVICE_ID_SIZE    1024
72
73 /* ioctls: */
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_CTL_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 /*
132  * Locks down the locking order:
133  * ->wmut locks wstatus.
134  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
135  * [rw]status. We only touch status when we know the side idle.
136  * ->lock locks what interrupt accesses.
137  */
138 struct usblp {
139         struct usb_device       *dev;                   /* USB device */
140         struct mutex            wmut;
141         struct mutex            mut;
142         spinlock_t              lock;           /* locks rcomplete, wcomplete */
143         char                    *readbuf;               /* read transfer_buffer */
144         char                    *statusbuf;             /* status transfer_buffer */
145         struct usb_anchor       urbs;
146         wait_queue_head_t       rwait, wwait;
147         int                     readcount;              /* Counter for reads */
148         int                     ifnum;                  /* Interface number */
149         struct usb_interface    *intf;                  /* The interface */
150         /* Alternate-setting numbers and endpoints for each protocol
151          * (7/1/{index=1,2,3}) that the device supports: */
152         struct {
153                 int                             alt_setting;
154                 struct usb_endpoint_descriptor  *epwrite;
155                 struct usb_endpoint_descriptor  *epread;
156         }                       protocol[USBLP_MAX_PROTOCOLS];
157         int                     current_protocol;
158         int                     minor;                  /* minor number of device */
159         int                     wcomplete, rcomplete;
160         int                     wstatus;        /* bytes written or error */
161         int                     rstatus;        /* bytes ready or error */
162         unsigned int            quirks;                 /* quirks flags */
163         unsigned int            flags;                  /* mode flags */
164         unsigned char           used;                   /* True if open */
165         unsigned char           present;                /* True if not disconnected */
166         unsigned char           bidir;                  /* interface is bidirectional */
167         unsigned char           no_paper;               /* Paper Out happened */
168         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
169                                                         /* first 2 bytes are (big-endian) length */
170 };
171
172 #ifdef DEBUG
173 static void usblp_dump(struct usblp *usblp) {
174         int p;
175
176         dbg("usblp=0x%p", usblp);
177         dbg("dev=0x%p", usblp->dev);
178         dbg("present=%d", usblp->present);
179         dbg("readbuf=0x%p", usblp->readbuf);
180         dbg("readcount=%d", usblp->readcount);
181         dbg("ifnum=%d", usblp->ifnum);
182     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
183         dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
184         dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
185         dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
186     }
187         dbg("current_protocol=%d", usblp->current_protocol);
188         dbg("minor=%d", usblp->minor);
189         dbg("wstatus=%d", usblp->wstatus);
190         dbg("rstatus=%d", usblp->rstatus);
191         dbg("quirks=%d", usblp->quirks);
192         dbg("used=%d", usblp->used);
193         dbg("bidir=%d", usblp->bidir);
194         dbg("device_id_string=\"%s\"",
195                 usblp->device_id_string ?
196                         usblp->device_id_string + 2 :
197                         (unsigned char *)"(null)");
198 }
199 #endif
200
201 /* Quirks: various printer quirks are handled by this table & its flags. */
202
203 struct quirk_printer_struct {
204         __u16 vendorId;
205         __u16 productId;
206         unsigned int quirks;
207 };
208
209 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
210 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
211 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
212
213 static const struct quirk_printer_struct quirk_printers[] = {
214         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
215         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
216         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
217         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
218         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
219         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
220         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */   
221         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */   
222         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
223         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
224         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
225         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
226         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
227         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
228         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
229         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
230         { 0, 0 }
231 };
232
233 static int usblp_wwait(struct usblp *usblp, int nonblock);
234 static int usblp_wtest(struct usblp *usblp, int nonblock);
235 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
236 static int usblp_rtest(struct usblp *usblp, int nonblock);
237 static int usblp_submit_read(struct usblp *usblp);
238 static int usblp_select_alts(struct usblp *usblp);
239 static int usblp_set_protocol(struct usblp *usblp, int protocol);
240 static int usblp_cache_device_id_string(struct usblp *usblp);
241
242 /* forward reference to make our lives easier */
243 static struct usb_driver usblp_driver;
244 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
245
246 /*
247  * Functions for usblp control messages.
248  */
249
250 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
251 {
252         int retval;
253         int index = usblp->ifnum;
254
255         /* High byte has the interface index.
256            Low byte has the alternate setting.
257          */
258         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
259           index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
260         }
261
262         retval = usb_control_msg(usblp->dev,
263                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
264                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
265         dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
266                 request, !!dir, recip, value, index, len, retval);
267         return retval < 0 ? retval : 0;
268 }
269
270 #define usblp_read_status(usblp, status)\
271         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
272 #define usblp_get_id(usblp, config, id, maxlen)\
273         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
274 #define usblp_reset(usblp)\
275         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
276
277 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
278         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
279
280 /*
281  * See the description for usblp_select_alts() below for the usage
282  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
283  * case of any trouble.
284  */
285 static int proto_bias = -1;
286
287 /*
288  * URB callback.
289  */
290
291 static void usblp_bulk_read(struct urb *urb)
292 {
293         struct usblp *usblp = urb->context;
294         int status = urb->status;
295
296         if (usblp->present && usblp->used) {
297                 if (status)
298                         printk(KERN_WARNING "usblp%d: "
299                             "nonzero read bulk status received: %d\n",
300                             usblp->minor, status);
301         }
302         spin_lock(&usblp->lock);
303         if (status < 0)
304                 usblp->rstatus = status;
305         else
306                 usblp->rstatus = urb->actual_length;
307         usblp->rcomplete = 1;
308         wake_up(&usblp->rwait);
309         spin_unlock(&usblp->lock);
310
311         usb_free_urb(urb);
312 }
313
314 static void usblp_bulk_write(struct urb *urb)
315 {
316         struct usblp *usblp = urb->context;
317         int status = urb->status;
318
319         if (usblp->present && usblp->used) {
320                 if (status)
321                         printk(KERN_WARNING "usblp%d: "
322                             "nonzero write bulk status received: %d\n",
323                             usblp->minor, status);
324         }
325         spin_lock(&usblp->lock);
326         if (status < 0)
327                 usblp->wstatus = status;
328         else
329                 usblp->wstatus = urb->actual_length;
330         usblp->no_paper = 0;
331         usblp->wcomplete = 1;
332         wake_up(&usblp->wwait);
333         spin_unlock(&usblp->lock);
334
335         usb_free_urb(urb);
336 }
337
338 /*
339  * Get and print printer errors.
340  */
341
342 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
343
344 static int usblp_check_status(struct usblp *usblp, int err)
345 {
346         unsigned char status, newerr = 0;
347         int error;
348
349         mutex_lock(&usblp->mut);
350         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
351                 mutex_unlock(&usblp->mut);
352                 if (printk_ratelimit())
353                         printk(KERN_ERR
354                                 "usblp%d: error %d reading printer status\n",
355                                 usblp->minor, error);
356                 return 0;
357         }
358         status = *usblp->statusbuf;
359         mutex_unlock(&usblp->mut);
360
361         if (~status & LP_PERRORP)
362                 newerr = 3;
363         if (status & LP_POUTPA)
364                 newerr = 1;
365         if (~status & LP_PSELECD)
366                 newerr = 2;
367
368         if (newerr != err) {
369                 printk(KERN_INFO "usblp%d: %s\n",
370                    usblp->minor, usblp_messages[newerr]);
371         }
372
373         return newerr;
374 }
375
376 static int handle_bidir (struct usblp *usblp)
377 {
378         if (usblp->bidir && usblp->used) {
379                 if (usblp_submit_read(usblp) < 0)
380                         return -EIO;
381         }
382         return 0;
383 }
384
385 /*
386  * File op functions.
387  */
388
389 static int usblp_open(struct inode *inode, struct file *file)
390 {
391         int minor = iminor(inode);
392         struct usblp *usblp;
393         struct usb_interface *intf;
394         int retval;
395
396         if (minor < 0)
397                 return -ENODEV;
398
399         lock_kernel();
400         mutex_lock (&usblp_mutex);
401
402         retval = -ENODEV;
403         intf = usb_find_interface(&usblp_driver, minor);
404         if (!intf) {
405                 goto out;
406         }
407         usblp = usb_get_intfdata (intf);
408         if (!usblp || !usblp->dev || !usblp->present)
409                 goto out;
410
411         retval = -EBUSY;
412         if (usblp->used)
413                 goto out;
414
415         /*
416          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
417          *  - We do not want persistent state which close(2) does not clear
418          *  - It is not used anyway, according to CUPS people
419          */
420
421         retval = usb_autopm_get_interface(intf);
422         if (retval < 0)
423                 goto out;
424         usblp->used = 1;
425         file->private_data = usblp;
426
427         usblp->wcomplete = 1; /* we begin writeable */
428         usblp->wstatus = 0;
429         usblp->rcomplete = 0;
430
431         if (handle_bidir(usblp) < 0) {
432                 usb_autopm_put_interface(intf);
433                 usblp->used = 0;
434                 file->private_data = NULL;
435                 retval = -EIO;
436         }
437 out:
438         mutex_unlock (&usblp_mutex);
439         unlock_kernel();
440         return retval;
441 }
442
443 static void usblp_cleanup (struct usblp *usblp)
444 {
445         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
446
447         kfree(usblp->readbuf);
448         kfree (usblp->device_id_string);
449         kfree (usblp->statusbuf);
450         kfree (usblp);
451 }
452
453 static void usblp_unlink_urbs(struct usblp *usblp)
454 {
455         usb_kill_anchored_urbs(&usblp->urbs);
456 }
457
458 static int usblp_release(struct inode *inode, struct file *file)
459 {
460         struct usblp *usblp = file->private_data;
461
462         usblp->flags &= ~LP_ABORT;
463
464         mutex_lock (&usblp_mutex);
465         usblp->used = 0;
466         if (usblp->present) {
467                 usblp_unlink_urbs(usblp);
468                 usb_autopm_put_interface(usblp->intf);
469         } else          /* finish cleanup from disconnect */
470                 usblp_cleanup (usblp);
471         mutex_unlock (&usblp_mutex);
472         return 0;
473 }
474
475 /* No kernel lock - fine */
476 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
477 {
478         int ret;
479         unsigned long flags;
480
481         struct usblp *usblp = file->private_data;
482         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
483         poll_wait(file, &usblp->rwait, wait);
484         poll_wait(file, &usblp->wwait, wait);
485         spin_lock_irqsave(&usblp->lock, flags);
486         ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
487            ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
488         spin_unlock_irqrestore(&usblp->lock, flags);
489         return ret;
490 }
491
492 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
493 {
494         struct usblp *usblp = file->private_data;
495         int length, err, i;
496         unsigned char newChannel;
497         int status;
498         int twoints[2];
499         int retval = 0;
500
501         mutex_lock (&usblp->mut);
502         if (!usblp->present) {
503                 retval = -ENODEV;
504                 goto done;
505         }
506
507         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
508                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
509
510         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
511
512                 switch (_IOC_NR(cmd)) {
513
514                         case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
515                                 if (_IOC_DIR(cmd) != _IOC_READ) {
516                                         retval = -EINVAL;
517                                         goto done;
518                                 }
519
520                                 length = usblp_cache_device_id_string(usblp);
521                                 if (length < 0) {
522                                         retval = length;
523                                         goto done;
524                                 }
525                                 if (length > _IOC_SIZE(cmd))
526                                         length = _IOC_SIZE(cmd); /* truncate */
527
528                                 if (copy_to_user((void __user *) arg,
529                                                 usblp->device_id_string,
530                                                 (unsigned long) length)) {
531                                         retval = -EFAULT;
532                                         goto done;
533                                 }
534
535                                 break;
536
537                         case IOCNR_GET_PROTOCOLS:
538                                 if (_IOC_DIR(cmd) != _IOC_READ ||
539                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
540                                         retval = -EINVAL;
541                                         goto done;
542                                 }
543
544                                 twoints[0] = usblp->current_protocol;
545                                 twoints[1] = 0;
546                                 for (i = USBLP_FIRST_PROTOCOL;
547                                      i <= USBLP_LAST_PROTOCOL; i++) {
548                                         if (usblp->protocol[i].alt_setting >= 0)
549                                                 twoints[1] |= (1<<i);
550                                 }
551
552                                 if (copy_to_user((void __user *)arg,
553                                                 (unsigned char *)twoints,
554                                                 sizeof(twoints))) {
555                                         retval = -EFAULT;
556                                         goto done;
557                                 }
558
559                                 break;
560
561                         case IOCNR_SET_PROTOCOL:
562                                 if (_IOC_DIR(cmd) != _IOC_WRITE) {
563                                         retval = -EINVAL;
564                                         goto done;
565                                 }
566
567 #ifdef DEBUG
568                                 if (arg == -10) {
569                                         usblp_dump(usblp);
570                                         break;
571                                 }
572 #endif
573
574                                 usblp_unlink_urbs(usblp);
575                                 retval = usblp_set_protocol(usblp, arg);
576                                 if (retval < 0) {
577                                         usblp_set_protocol(usblp,
578                                                 usblp->current_protocol);
579                                 }
580                                 break;
581
582                         case IOCNR_HP_SET_CHANNEL:
583                                 if (_IOC_DIR(cmd) != _IOC_WRITE ||
584                                     le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
585                                     usblp->quirks & USBLP_QUIRK_BIDIR) {
586                                         retval = -EINVAL;
587                                         goto done;
588                                 }
589
590                                 err = usblp_hp_channel_change_request(usblp,
591                                         arg, &newChannel);
592                                 if (err < 0) {
593                                         dev_err(&usblp->dev->dev,
594                                                 "usblp%d: error = %d setting "
595                                                 "HP channel\n",
596                                                 usblp->minor, err);
597                                         retval = -EIO;
598                                         goto done;
599                                 }
600
601                                 dbg("usblp%d requested/got HP channel %ld/%d",
602                                         usblp->minor, arg, newChannel);
603                                 break;
604
605                         case IOCNR_GET_BUS_ADDRESS:
606                                 if (_IOC_DIR(cmd) != _IOC_READ ||
607                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
608                                         retval = -EINVAL;
609                                         goto done;
610                                 }
611
612                                 twoints[0] = usblp->dev->bus->busnum;
613                                 twoints[1] = usblp->dev->devnum;
614                                 if (copy_to_user((void __user *)arg,
615                                                 (unsigned char *)twoints,
616                                                 sizeof(twoints))) {
617                                         retval = -EFAULT;
618                                         goto done;
619                                 }
620
621                                 dbg("usblp%d is bus=%d, device=%d",
622                                         usblp->minor, twoints[0], twoints[1]);
623                                 break;
624
625                         case IOCNR_GET_VID_PID:
626                                 if (_IOC_DIR(cmd) != _IOC_READ ||
627                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
628                                         retval = -EINVAL;
629                                         goto done;
630                                 }
631
632                                 twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
633                                 twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
634                                 if (copy_to_user((void __user *)arg,
635                                                 (unsigned char *)twoints,
636                                                 sizeof(twoints))) {
637                                         retval = -EFAULT;
638                                         goto done;
639                                 }
640
641                                 dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
642                                         usblp->minor, twoints[0], twoints[1]);
643                                 break;
644
645                         case IOCNR_SOFT_RESET:
646                                 if (_IOC_DIR(cmd) != _IOC_NONE) {
647                                         retval = -EINVAL;
648                                         goto done;
649                                 }
650                                 retval = usblp_reset(usblp);
651                                 break;
652                         default:
653                                 retval = -ENOTTY;
654                 }
655         else    /* old-style ioctl value */
656                 switch (cmd) {
657
658                         case LPGETSTATUS:
659                                 if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
660                                         if (printk_ratelimit())
661                                                 printk(KERN_ERR "usblp%d:"
662                                                     "failed reading printer status (%d)\n",
663                                                     usblp->minor, retval);
664                                         retval = -EIO;
665                                         goto done;
666                                 }
667                                 status = *usblp->statusbuf;
668                                 if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
669                                         retval = -EFAULT;
670                                 break;
671
672                         case LPABORT:
673                                 if (arg)
674                                         usblp->flags |= LP_ABORT;
675                                 else
676                                         usblp->flags &= ~LP_ABORT;
677                                 break;
678
679                         default:
680                                 retval = -ENOTTY;
681                 }
682
683 done:
684         mutex_unlock (&usblp->mut);
685         return retval;
686 }
687
688 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
689 {
690         struct urb *urb;
691         char *writebuf;
692
693         if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
694                 return NULL;
695         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
696                 kfree(writebuf);
697                 return NULL;
698         }
699
700         usb_fill_bulk_urb(urb, usblp->dev,
701                 usb_sndbulkpipe(usblp->dev,
702                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
703                 writebuf, transfer_length, usblp_bulk_write, usblp);
704         urb->transfer_flags |= URB_FREE_BUFFER;
705
706         return urb;
707 }
708
709 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
710 {
711         struct usblp *usblp = file->private_data;
712         struct urb *writeurb;
713         int rv;
714         int transfer_length;
715         ssize_t writecount = 0;
716
717         if (mutex_lock_interruptible(&usblp->wmut)) {
718                 rv = -EINTR;
719                 goto raise_biglock;
720         }
721         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
722                 goto raise_wait;
723
724         while (writecount < count) {
725                 /*
726                  * Step 1: Submit next block.
727                  */
728                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
729                         transfer_length = USBLP_BUF_SIZE;
730
731                 rv = -ENOMEM;
732                 if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
733                         goto raise_urb;
734                 usb_anchor_urb(writeurb, &usblp->urbs);
735
736                 if (copy_from_user(writeurb->transfer_buffer,
737                                    buffer + writecount, transfer_length)) {
738                         rv = -EFAULT;
739                         goto raise_badaddr;
740                 }
741
742                 spin_lock_irq(&usblp->lock);
743                 usblp->wcomplete = 0;
744                 spin_unlock_irq(&usblp->lock);
745                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
746                         usblp->wstatus = 0;
747                         spin_lock_irq(&usblp->lock);
748                         usblp->no_paper = 0;
749                         usblp->wcomplete = 1;
750                         wake_up(&usblp->wwait);
751                         spin_unlock_irq(&usblp->lock);
752                         if (rv != -ENOMEM)
753                                 rv = -EIO;
754                         goto raise_submit;
755                 }
756
757                 /*
758                  * Step 2: Wait for transfer to end, collect results.
759                  */
760                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
761                 if (rv < 0) {
762                         if (rv == -EAGAIN) {
763                                 /* Presume that it's going to complete well. */
764                                 writecount += transfer_length;
765                         }
766                         if (rv == -ENOSPC) {
767                                 spin_lock_irq(&usblp->lock);
768                                 usblp->no_paper = 1;    /* Mark for poll(2) */
769                                 spin_unlock_irq(&usblp->lock);
770                                 writecount += transfer_length;
771                         }
772                         /* Leave URB dangling, to be cleaned on close. */
773                         goto collect_error;
774                 }
775
776                 if (usblp->wstatus < 0) {
777                         rv = -EIO;
778                         goto collect_error;
779                 }
780                 /*
781                  * This is critical: it must be our URB, not other writer's.
782                  * The wmut exists mainly to cover us here.
783                  */
784                 writecount += usblp->wstatus;
785         }
786
787         mutex_unlock(&usblp->wmut);
788         return writecount;
789
790 raise_submit:
791 raise_badaddr:
792         usb_unanchor_urb(writeurb);
793         usb_free_urb(writeurb);
794 raise_urb:
795 raise_wait:
796 collect_error:          /* Out of raise sequence */
797         mutex_unlock(&usblp->wmut);
798 raise_biglock:
799         return writecount ? writecount : rv;
800 }
801
802 /*
803  * Notice that we fail to restart in a few cases: on EFAULT, on restart
804  * error, etc. This is the historical behaviour. In all such cases we return
805  * EIO, and applications loop in order to get the new read going.
806  */
807 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
808 {
809         struct usblp *usblp = file->private_data;
810         ssize_t count;
811         ssize_t avail;
812         int rv;
813
814         if (!usblp->bidir)
815                 return -EINVAL;
816
817         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
818         if (rv < 0)
819                 return rv;
820
821         if ((avail = usblp->rstatus) < 0) {
822                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
823                     usblp->minor, (int)avail);
824                 usblp_submit_read(usblp);
825                 count = -EIO;
826                 goto done;
827         }
828
829         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
830         if (count != 0 &&
831             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
832                 count = -EFAULT;
833                 goto done;
834         }
835
836         if ((usblp->readcount += count) == avail) {
837                 if (usblp_submit_read(usblp) < 0) {
838                         /* We don't want to leak USB return codes into errno. */
839                         if (count == 0)
840                                 count = -EIO;
841                         goto done;
842                 }
843         }
844
845 done:
846         mutex_unlock (&usblp->mut);
847         return count;
848 }
849
850 /*
851  * Wait for the write path to come idle.
852  * This is called under the ->wmut, so the idle path stays idle.
853  *
854  * Our write path has a peculiar property: it does not buffer like a tty,
855  * but waits for the write to succeed. This allows our ->release to bug out
856  * without waiting for writes to drain. But it obviously does not work
857  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
858  * select(2) or poll(2) to wait for the buffer to drain before closing.
859  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
860  */
861 static int usblp_wwait(struct usblp *usblp, int nonblock)
862 {
863         DECLARE_WAITQUEUE(waita, current);
864         int rc;
865         int err = 0;
866
867         add_wait_queue(&usblp->wwait, &waita);
868         for (;;) {
869                 set_current_state(TASK_INTERRUPTIBLE);
870                 if (mutex_lock_interruptible(&usblp->mut)) {
871                         rc = -EINTR;
872                         break;
873                 }
874                 rc = usblp_wtest(usblp, nonblock);
875                 mutex_unlock(&usblp->mut);
876                 if (rc <= 0)
877                         break;
878
879                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
880                         if (usblp->flags & LP_ABORT) {
881                                 err = usblp_check_status(usblp, err);
882                                 if (err == 1) { /* Paper out */
883                                         rc = -ENOSPC;
884                                         break;
885                                 }
886                         } else {
887                                 /* Prod the printer, Gentoo#251237. */
888                                 mutex_lock(&usblp->mut);
889                                 usblp_read_status(usblp, usblp->statusbuf);
890                                 mutex_unlock(&usblp->mut);
891                         }
892                 }
893         }
894         set_current_state(TASK_RUNNING);
895         remove_wait_queue(&usblp->wwait, &waita);
896         return rc;
897 }
898
899 static int usblp_wtest(struct usblp *usblp, int nonblock)
900 {
901         unsigned long flags;
902
903         if (!usblp->present)
904                 return -ENODEV;
905         if (signal_pending(current))
906                 return -EINTR;
907         spin_lock_irqsave(&usblp->lock, flags);
908         if (usblp->wcomplete) {
909                 spin_unlock_irqrestore(&usblp->lock, flags);
910                 return 0;
911         }
912         spin_unlock_irqrestore(&usblp->lock, flags);
913         if (nonblock)
914                 return -EAGAIN;
915         return 1;
916 }
917
918 /*
919  * Wait for read bytes to become available. This probably should have been
920  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
921  * name for functions which lock and return.
922  *
923  * We do not use wait_event_interruptible because it makes locking iffy.
924  */
925 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
926 {
927         DECLARE_WAITQUEUE(waita, current);
928         int rc;
929
930         add_wait_queue(&usblp->rwait, &waita);
931         for (;;) {
932                 if (mutex_lock_interruptible(&usblp->mut)) {
933                         rc = -EINTR;
934                         break;
935                 }
936                 set_current_state(TASK_INTERRUPTIBLE);
937                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
938                         mutex_unlock(&usblp->mut);
939                         break;
940                 }
941                 if (rc == 0)    /* Keep it locked */
942                         break;
943                 mutex_unlock(&usblp->mut);
944                 schedule();
945         }
946         set_current_state(TASK_RUNNING);
947         remove_wait_queue(&usblp->rwait, &waita);
948         return rc;
949 }
950
951 static int usblp_rtest(struct usblp *usblp, int nonblock)
952 {
953         unsigned long flags;
954
955         if (!usblp->present)
956                 return -ENODEV;
957         if (signal_pending(current))
958                 return -EINTR;
959         spin_lock_irqsave(&usblp->lock, flags);
960         if (usblp->rcomplete) {
961                 spin_unlock_irqrestore(&usblp->lock, flags);
962                 return 0;
963         }
964         spin_unlock_irqrestore(&usblp->lock, flags);
965         if (nonblock)
966                 return -EAGAIN;
967         return 1;
968 }
969
970 /*
971  * Please check ->bidir and other such things outside for now.
972  */
973 static int usblp_submit_read(struct usblp *usblp)
974 {
975         struct urb *urb;
976         unsigned long flags;
977         int rc;
978
979         rc = -ENOMEM;
980         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
981                 goto raise_urb;
982
983         usb_fill_bulk_urb(urb, usblp->dev,
984                 usb_rcvbulkpipe(usblp->dev,
985                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
986                 usblp->readbuf, USBLP_BUF_SIZE_IN,
987                 usblp_bulk_read, usblp);
988         usb_anchor_urb(urb, &usblp->urbs);
989
990         spin_lock_irqsave(&usblp->lock, flags);
991         usblp->readcount = 0; /* XXX Why here? */
992         usblp->rcomplete = 0;
993         spin_unlock_irqrestore(&usblp->lock, flags);
994         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
995                 dbg("error submitting urb (%d)", rc);
996                 spin_lock_irqsave(&usblp->lock, flags);
997                 usblp->rstatus = rc;
998                 usblp->rcomplete = 1;
999                 spin_unlock_irqrestore(&usblp->lock, flags);
1000                 goto raise_submit;
1001         }
1002
1003         return 0;
1004
1005 raise_submit:
1006         usb_unanchor_urb(urb);
1007         usb_free_urb(urb);
1008 raise_urb:
1009         return rc;
1010 }
1011
1012 /*
1013  * Checks for printers that have quirks, such as requiring unidirectional
1014  * communication but reporting bidirectional; currently some HP printers
1015  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1016  * sent at each open (like some Epsons).
1017  * Returns 1 if found, 0 if not found.
1018  *
1019  * HP recommended that we use the bidirectional interface but
1020  * don't attempt any bulk IN transfers from the IN endpoint.
1021  * Here's some more detail on the problem:
1022  * The problem is not that it isn't bidirectional though. The problem
1023  * is that if you request a device ID, or status information, while
1024  * the buffers are full, the return data will end up in the print data
1025  * buffer. For example if you make sure you never request the device ID
1026  * while you are sending print data, and you don't try to query the
1027  * printer status every couple of milliseconds, you will probably be OK.
1028  */
1029 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
1030 {
1031         int i;
1032
1033         for (i = 0; quirk_printers[i].vendorId; i++) {
1034                 if (vendor == quirk_printers[i].vendorId &&
1035                     product == quirk_printers[i].productId)
1036                         return quirk_printers[i].quirks;
1037         }
1038         return 0;
1039 }
1040
1041 static const struct file_operations usblp_fops = {
1042         .owner =        THIS_MODULE,
1043         .read =         usblp_read,
1044         .write =        usblp_write,
1045         .poll =         usblp_poll,
1046         .unlocked_ioctl =       usblp_ioctl,
1047         .compat_ioctl =         usblp_ioctl,
1048         .open =         usblp_open,
1049         .release =      usblp_release,
1050 };
1051
1052 static char *usblp_devnode(struct device *dev, mode_t *mode)
1053 {
1054         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1055 }
1056
1057 static struct usb_class_driver usblp_class = {
1058         .name =         "lp%d",
1059         .devnode =      usblp_devnode,
1060         .fops =         &usblp_fops,
1061         .minor_base =   USBLP_MINOR_BASE,
1062 };
1063
1064 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1065 {
1066         struct usb_interface *intf = to_usb_interface(dev);
1067         struct usblp *usblp = usb_get_intfdata (intf);
1068
1069         if (usblp->device_id_string[0] == 0 &&
1070             usblp->device_id_string[1] == 0)
1071                 return 0;
1072
1073         return sprintf(buf, "%s", usblp->device_id_string+2);
1074 }
1075
1076 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1077
1078 static int usblp_probe(struct usb_interface *intf,
1079                        const struct usb_device_id *id)
1080 {
1081         struct usb_device *dev = interface_to_usbdev (intf);
1082         struct usblp *usblp;
1083         int protocol;
1084         int retval;
1085
1086         /* Malloc and start initializing usblp structure so we can use it
1087          * directly. */
1088         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1089         if (!usblp) {
1090                 retval = -ENOMEM;
1091                 goto abort_ret;
1092         }
1093         usblp->dev = dev;
1094         mutex_init(&usblp->wmut);
1095         mutex_init (&usblp->mut);
1096         spin_lock_init(&usblp->lock);
1097         init_waitqueue_head(&usblp->rwait);
1098         init_waitqueue_head(&usblp->wwait);
1099         init_usb_anchor(&usblp->urbs);
1100         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1101         usblp->intf = intf;
1102
1103         /* Malloc device ID string buffer to the largest expected length,
1104          * since we can re-query it on an ioctl and a dynamic string
1105          * could change in length. */
1106         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1107                 retval = -ENOMEM;
1108                 goto abort;
1109         }
1110
1111         /*
1112          * Allocate read buffer. We somewhat wastefully
1113          * malloc both regardless of bidirectionality, because the
1114          * alternate setting can be changed later via an ioctl.
1115          */
1116         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1117                 retval = -ENOMEM;
1118                 goto abort;
1119         }
1120
1121         /* Allocate buffer for printer status */
1122         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1123         if (!usblp->statusbuf) {
1124                 retval = -ENOMEM;
1125                 goto abort;
1126         }
1127
1128         /* Lookup quirks for this printer. */
1129         usblp->quirks = usblp_quirks(
1130                 le16_to_cpu(dev->descriptor.idVendor),
1131                 le16_to_cpu(dev->descriptor.idProduct));
1132
1133         /* Analyze and pick initial alternate settings and endpoints. */
1134         protocol = usblp_select_alts(usblp);
1135         if (protocol < 0) {
1136                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
1137                         le16_to_cpu(dev->descriptor.idVendor),
1138                         le16_to_cpu(dev->descriptor.idProduct));
1139                 retval = -ENODEV;
1140                 goto abort;
1141         }
1142
1143         /* Setup the selected alternate setting and endpoints. */
1144         if (usblp_set_protocol(usblp, protocol) < 0) {
1145                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1146                 goto abort;
1147         }
1148
1149         /* Retrieve and store the device ID string. */
1150         usblp_cache_device_id_string(usblp);
1151         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1152         if (retval)
1153                 goto abort_intfdata;
1154
1155 #ifdef DEBUG
1156         usblp_check_status(usblp, 0);
1157 #endif
1158
1159         usb_set_intfdata (intf, usblp);
1160
1161         usblp->present = 1;
1162
1163         retval = usb_register_dev(intf, &usblp_class);
1164         if (retval) {
1165                 printk(KERN_ERR "usblp: Not able to get a minor"
1166                     " (base %u, slice default): %d\n",
1167                     USBLP_MINOR_BASE, retval);
1168                 goto abort_intfdata;
1169         }
1170         usblp->minor = intf->minor;
1171         printk(KERN_INFO "usblp%d: USB %sdirectional printer dev %d "
1172                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1173                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1174                 usblp->ifnum,
1175                 usblp->protocol[usblp->current_protocol].alt_setting,
1176                 usblp->current_protocol,
1177                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1178                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1179
1180         return 0;
1181
1182 abort_intfdata:
1183         usb_set_intfdata (intf, NULL);
1184         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1185 abort:
1186         kfree(usblp->readbuf);
1187         kfree(usblp->statusbuf);
1188         kfree(usblp->device_id_string);
1189         kfree(usblp);
1190 abort_ret:
1191         return retval;
1192 }
1193
1194 /*
1195  * We are a "new" style driver with usb_device_id table,
1196  * but our requirements are too intricate for simple match to handle.
1197  *
1198  * The "proto_bias" option may be used to specify the preferred protocol
1199  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1200  * supports the preferred protocol, then we bind to it.
1201  *
1202  * The best interface for us is 7/1/2, because it is compatible
1203  * with a stream of characters. If we find it, we bind to it.
1204  *
1205  * Note that the people from hpoj.sourceforge.net need to be able to
1206  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1207  *
1208  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1209  * stream-compatible, because this matches the behaviour of the old code.
1210  *
1211  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1212  */
1213 static int usblp_select_alts(struct usblp *usblp)
1214 {
1215         struct usb_interface *if_alt;
1216         struct usb_host_interface *ifd;
1217         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1218         int p, i, e;
1219
1220         if_alt = usblp->intf;
1221
1222         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1223                 usblp->protocol[p].alt_setting = -1;
1224
1225         /* Find out what we have. */
1226         for (i = 0; i < if_alt->num_altsetting; i++) {
1227                 ifd = &if_alt->altsetting[i];
1228
1229                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1230                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1231                                 continue;
1232
1233                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1234                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1235                         continue;
1236
1237                 /* Look for bulk OUT and IN endpoints. */
1238                 epwrite = epread = NULL;
1239                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1240                         epd = &ifd->endpoint[e].desc;
1241
1242                         if (usb_endpoint_is_bulk_out(epd))
1243                                 if (!epwrite)
1244                                         epwrite = epd;
1245
1246                         if (usb_endpoint_is_bulk_in(epd))
1247                                 if (!epread)
1248                                         epread = epd;
1249                 }
1250
1251                 /* Ignore buggy hardware without the right endpoints. */
1252                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1253                         continue;
1254
1255                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1256                  * and buggy bidirectional printers. */
1257                 if (ifd->desc.bInterfaceProtocol == 1) {
1258                         epread = NULL;
1259                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1260                         printk(KERN_INFO "usblp%d: Disabling reads from "
1261                             "problematic bidirectional printer\n",
1262                             usblp->minor);
1263                         epread = NULL;
1264                 }
1265
1266                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1267                                 ifd->desc.bAlternateSetting;
1268                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1269                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1270         }
1271
1272         /* If our requested protocol is supported, then use it. */
1273         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1274             proto_bias <= USBLP_LAST_PROTOCOL &&
1275             usblp->protocol[proto_bias].alt_setting != -1)
1276                 return proto_bias;
1277
1278         /* Ordering is important here. */
1279         if (usblp->protocol[2].alt_setting != -1)
1280                 return 2;
1281         if (usblp->protocol[1].alt_setting != -1)
1282                 return 1;
1283         if (usblp->protocol[3].alt_setting != -1)
1284                 return 3;
1285
1286         /* If nothing is available, then don't bind to this device. */
1287         return -1;
1288 }
1289
1290 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1291 {
1292         int r, alts;
1293
1294         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1295                 return -EINVAL;
1296
1297         alts = usblp->protocol[protocol].alt_setting;
1298         if (alts < 0)
1299                 return -EINVAL;
1300         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1301         if (r < 0) {
1302                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1303                         alts, usblp->ifnum);
1304                 return r;
1305         }
1306
1307         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1308         usblp->current_protocol = protocol;
1309         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1310         return 0;
1311 }
1312
1313 /* Retrieves and caches device ID string.
1314  * Returns length, including length bytes but not null terminator.
1315  * On error, returns a negative errno value. */
1316 static int usblp_cache_device_id_string(struct usblp *usblp)
1317 {
1318         int err, length;
1319
1320         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1321         if (err < 0) {
1322                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1323                         usblp->minor, err);
1324                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1325                 return -EIO;
1326         }
1327
1328         /* First two bytes are length in big-endian.
1329          * They count themselves, and we copy them into
1330          * the user's buffer. */
1331         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1332         if (length < 2)
1333                 length = 2;
1334         else if (length >= USBLP_DEVICE_ID_SIZE)
1335                 length = USBLP_DEVICE_ID_SIZE - 1;
1336         usblp->device_id_string[length] = '\0';
1337
1338         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1339                 usblp->minor, length, &usblp->device_id_string[2]);
1340
1341         return length;
1342 }
1343
1344 static void usblp_disconnect(struct usb_interface *intf)
1345 {
1346         struct usblp *usblp = usb_get_intfdata (intf);
1347
1348         usb_deregister_dev(intf, &usblp_class);
1349
1350         if (!usblp || !usblp->dev) {
1351                 dev_err(&intf->dev, "bogus disconnect\n");
1352                 BUG ();
1353         }
1354
1355         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1356
1357         mutex_lock (&usblp_mutex);
1358         mutex_lock (&usblp->mut);
1359         usblp->present = 0;
1360         wake_up(&usblp->wwait);
1361         wake_up(&usblp->rwait);
1362         usb_set_intfdata (intf, NULL);
1363
1364         usblp_unlink_urbs(usblp);
1365         mutex_unlock (&usblp->mut);
1366
1367         if (!usblp->used)
1368                 usblp_cleanup (usblp);
1369         mutex_unlock (&usblp_mutex);
1370 }
1371
1372 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1373 {
1374         struct usblp *usblp = usb_get_intfdata (intf);
1375
1376         usblp_unlink_urbs(usblp);
1377 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1378         /* not strictly necessary, but just in case */
1379         wake_up(&usblp->wwait);
1380         wake_up(&usblp->rwait);
1381 #endif
1382
1383         return 0;
1384 }
1385
1386 static int usblp_resume(struct usb_interface *intf)
1387 {
1388         struct usblp *usblp = usb_get_intfdata (intf);
1389         int r;
1390
1391         r = handle_bidir (usblp);
1392
1393         return r;
1394 }
1395
1396 static const struct usb_device_id usblp_ids[] = {
1397         { USB_DEVICE_INFO(7, 1, 1) },
1398         { USB_DEVICE_INFO(7, 1, 2) },
1399         { USB_DEVICE_INFO(7, 1, 3) },
1400         { USB_INTERFACE_INFO(7, 1, 1) },
1401         { USB_INTERFACE_INFO(7, 1, 2) },
1402         { USB_INTERFACE_INFO(7, 1, 3) },
1403         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1404         { }                                             /* Terminating entry */
1405 };
1406
1407 MODULE_DEVICE_TABLE (usb, usblp_ids);
1408
1409 static struct usb_driver usblp_driver = {
1410         .name =         "usblp",
1411         .probe =        usblp_probe,
1412         .disconnect =   usblp_disconnect,
1413         .suspend =      usblp_suspend,
1414         .resume =       usblp_resume,
1415         .id_table =     usblp_ids,
1416         .supports_autosuspend = 1,
1417 };
1418
1419 static int __init usblp_init(void)
1420 {
1421         return usb_register(&usblp_driver);
1422 }
1423
1424 static void __exit usblp_exit(void)
1425 {
1426         usb_deregister(&usblp_driver);
1427 }
1428
1429 module_init(usblp_init);
1430 module_exit(usblp_exit);
1431
1432 MODULE_AUTHOR( DRIVER_AUTHOR );
1433 MODULE_DESCRIPTION( DRIVER_DESC );
1434 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1435 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1436 MODULE_LICENSE("GPL");