USB: Avoid PM error messages during resume if a device was disconnected
[linux-2.6] / 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 #undef DEBUG
60 #include <linux/usb.h>
61
62 /*
63  * Version Information
64  */
65 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
66 #define DRIVER_DESC "USB Printer Device Class driver"
67
68 #define USBLP_BUF_SIZE          8192
69 #define USBLP_BUF_SIZE_IN       1024
70 #define USBLP_DEVICE_ID_SIZE    1024
71
72 /* ioctls: */
73 #define IOCNR_GET_DEVICE_ID             1
74 #define IOCNR_GET_PROTOCOLS             2
75 #define IOCNR_SET_PROTOCOL              3
76 #define IOCNR_HP_SET_CHANNEL            4
77 #define IOCNR_GET_BUS_ADDRESS           5
78 #define IOCNR_GET_VID_PID               6
79 #define IOCNR_SOFT_RESET                7
80 /* Get device_id string: */
81 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
82 /* The following ioctls were added for http://hpoj.sourceforge.net: */
83 /* Get two-int array:
84  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
85  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
86 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
87 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
88 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
89 /* Set channel number (HP Vendor-specific command): */
90 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
91 /* Get two-int array: [0]=bus number, [1]=device address: */
92 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
93 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
94 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
95 /* Perform class specific soft reset */
96 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
97
98 /*
99  * A DEVICE_ID string may include the printer's serial number.
100  * It should end with a semi-colon (';').
101  * An example from an HP 970C DeskJet printer is (this is one long string,
102  * with the serial number changed):
103 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:                    ;
104  */
105
106 /*
107  * USB Printer Requests
108  */
109
110 #define USBLP_REQ_GET_ID                        0x00
111 #define USBLP_REQ_GET_STATUS                    0x01
112 #define USBLP_REQ_RESET                         0x02
113 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
114
115 #define USBLP_MINORS            16
116 #define USBLP_MINOR_BASE        0
117
118 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
119
120 #define USBLP_FIRST_PROTOCOL    1
121 #define USBLP_LAST_PROTOCOL     3
122 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
123
124 /*
125  * some arbitrary status buffer size;
126  * need a status buffer that is allocated via kmalloc(), not on stack
127  */
128 #define STATUS_BUF_SIZE         8
129
130 /*
131  * Locks down the locking order:
132  * ->wmut locks wstatus.
133  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
134  * [rw]status. We only touch status when we know the side idle.
135  * ->lock locks what interrupt accesses.
136  */
137 struct usblp {
138         struct usb_device       *dev;                   /* USB device */
139         struct mutex            wmut;
140         struct mutex            mut;
141         spinlock_t              lock;           /* locks rcomplete, wcomplete */
142         char                    *readbuf;               /* read transfer_buffer */
143         char                    *statusbuf;             /* status transfer_buffer */
144         struct usb_anchor       urbs;
145         wait_queue_head_t       rwait, wwait;
146         int                     readcount;              /* Counter for reads */
147         int                     ifnum;                  /* Interface number */
148         struct usb_interface    *intf;                  /* The interface */
149         /* Alternate-setting numbers and endpoints for each protocol
150          * (7/1/{index=1,2,3}) that the device supports: */
151         struct {
152                 int                             alt_setting;
153                 struct usb_endpoint_descriptor  *epwrite;
154                 struct usb_endpoint_descriptor  *epread;
155         }                       protocol[USBLP_MAX_PROTOCOLS];
156         int                     current_protocol;
157         int                     minor;                  /* minor number of device */
158         int                     wcomplete, rcomplete;
159         int                     wstatus;        /* bytes written or error */
160         int                     rstatus;        /* bytes ready or error */
161         unsigned int            quirks;                 /* quirks flags */
162         unsigned int            flags;                  /* mode flags */
163         unsigned char           used;                   /* True if open */
164         unsigned char           present;                /* True if not disconnected */
165         unsigned char           bidir;                  /* interface is bidirectional */
166         unsigned char           sleeping;               /* interface is suspended */
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("sleeping=%d", usblp->sleeping);
195         dbg("device_id_string=\"%s\"",
196                 usblp->device_id_string ?
197                         usblp->device_id_string + 2 :
198                         (unsigned char *)"(null)");
199 }
200 #endif
201
202 /* Quirks: various printer quirks are handled by this table & its flags. */
203
204 struct quirk_printer_struct {
205         __u16 vendorId;
206         __u16 productId;
207         unsigned int quirks;
208 };
209
210 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
211 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
212 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
213
214 static const struct quirk_printer_struct quirk_printers[] = {
215         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
216         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
217         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
218         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
219         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
220         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
221         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */   
222         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */   
223         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
224         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
225         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
226         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
227         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
228         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
229         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
230         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
231         { 0, 0 }
232 };
233
234 static int usblp_wwait(struct usblp *usblp, int nonblock);
235 static int usblp_wtest(struct usblp *usblp, int nonblock);
236 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
237 static int usblp_rtest(struct usblp *usblp, int nonblock);
238 static int usblp_submit_read(struct usblp *usblp);
239 static int usblp_select_alts(struct usblp *usblp);
240 static int usblp_set_protocol(struct usblp *usblp, int protocol);
241 static int usblp_cache_device_id_string(struct usblp *usblp);
242
243 /* forward reference to make our lives easier */
244 static struct usb_driver usblp_driver;
245 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
246
247 /*
248  * Functions for usblp control messages.
249  */
250
251 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
252 {
253         int retval;
254         int index = usblp->ifnum;
255
256         /* High byte has the interface index.
257            Low byte has the alternate setting.
258          */
259         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
260           index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
261         }
262
263         retval = usb_control_msg(usblp->dev,
264                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
265                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
266         dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
267                 request, !!dir, recip, value, index, len, retval);
268         return retval < 0 ? retval : 0;
269 }
270
271 #define usblp_read_status(usblp, status)\
272         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
273 #define usblp_get_id(usblp, config, id, maxlen)\
274         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
275 #define usblp_reset(usblp)\
276         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
277
278 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
279         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
280
281 /*
282  * See the description for usblp_select_alts() below for the usage
283  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
284  * case of any trouble.
285  */
286 static int proto_bias = -1;
287
288 /*
289  * URB callback.
290  */
291
292 static void usblp_bulk_read(struct urb *urb)
293 {
294         struct usblp *usblp = urb->context;
295         int status = urb->status;
296
297         if (usblp->present && usblp->used) {
298                 if (status)
299                         printk(KERN_WARNING "usblp%d: "
300                             "nonzero read bulk status received: %d\n",
301                             usblp->minor, status);
302         }
303         spin_lock(&usblp->lock);
304         if (status < 0)
305                 usblp->rstatus = status;
306         else
307                 usblp->rstatus = urb->actual_length;
308         usblp->rcomplete = 1;
309         wake_up(&usblp->rwait);
310         spin_unlock(&usblp->lock);
311
312         usb_free_urb(urb);
313 }
314
315 static void usblp_bulk_write(struct urb *urb)
316 {
317         struct usblp *usblp = urb->context;
318         int status = urb->status;
319
320         if (usblp->present && usblp->used) {
321                 if (status)
322                         printk(KERN_WARNING "usblp%d: "
323                             "nonzero write bulk status received: %d\n",
324                             usblp->minor, status);
325         }
326         spin_lock(&usblp->lock);
327         if (status < 0)
328                 usblp->wstatus = status;
329         else
330                 usblp->wstatus = urb->actual_length;
331         usblp->no_paper = 0;
332         usblp->wcomplete = 1;
333         wake_up(&usblp->wwait);
334         spin_unlock(&usblp->lock);
335
336         usb_free_urb(urb);
337 }
338
339 /*
340  * Get and print printer errors.
341  */
342
343 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
344
345 static int usblp_check_status(struct usblp *usblp, int err)
346 {
347         unsigned char status, newerr = 0;
348         int error;
349
350         mutex_lock(&usblp->mut);
351         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
352                 mutex_unlock(&usblp->mut);
353                 if (printk_ratelimit())
354                         printk(KERN_ERR
355                                 "usblp%d: error %d reading printer status\n",
356                                 usblp->minor, error);
357                 return 0;
358         }
359         status = *usblp->statusbuf;
360         mutex_unlock(&usblp->mut);
361
362         if (~status & LP_PERRORP)
363                 newerr = 3;
364         if (status & LP_POUTPA)
365                 newerr = 1;
366         if (~status & LP_PSELECD)
367                 newerr = 2;
368
369         if (newerr != err) {
370                 printk(KERN_INFO "usblp%d: %s\n",
371                    usblp->minor, usblp_messages[newerr]);
372         }
373
374         return newerr;
375 }
376
377 static int handle_bidir (struct usblp *usblp)
378 {
379         if (usblp->bidir && usblp->used && !usblp->sleeping) {
380                 if (usblp_submit_read(usblp) < 0)
381                         return -EIO;
382         }
383         return 0;
384 }
385
386 /*
387  * File op functions.
388  */
389
390 static int usblp_open(struct inode *inode, struct file *file)
391 {
392         int minor = iminor(inode);
393         struct usblp *usblp;
394         struct usb_interface *intf;
395         int retval;
396
397         if (minor < 0)
398                 return -ENODEV;
399
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         return retval;
440 }
441
442 static void usblp_cleanup (struct usblp *usblp)
443 {
444         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
445
446         kfree(usblp->readbuf);
447         kfree (usblp->device_id_string);
448         kfree (usblp->statusbuf);
449         kfree (usblp);
450 }
451
452 static void usblp_unlink_urbs(struct usblp *usblp)
453 {
454         usb_kill_anchored_urbs(&usblp->urbs);
455 }
456
457 static int usblp_release(struct inode *inode, struct file *file)
458 {
459         struct usblp *usblp = file->private_data;
460
461         usblp->flags &= ~LP_ABORT;
462
463         mutex_lock (&usblp_mutex);
464         usblp->used = 0;
465         if (usblp->present) {
466                 usblp_unlink_urbs(usblp);
467                 usb_autopm_put_interface(usblp->intf);
468         } else          /* finish cleanup from disconnect */
469                 usblp_cleanup (usblp);
470         mutex_unlock (&usblp_mutex);
471         return 0;
472 }
473
474 /* No kernel lock - fine */
475 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
476 {
477         int ret;
478         unsigned long flags;
479
480         struct usblp *usblp = file->private_data;
481         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
482         poll_wait(file, &usblp->rwait, wait);
483         poll_wait(file, &usblp->wwait, wait);
484         spin_lock_irqsave(&usblp->lock, flags);
485         ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
486            ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
487         spin_unlock_irqrestore(&usblp->lock, flags);
488         return ret;
489 }
490
491 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
492 {
493         struct usblp *usblp = file->private_data;
494         int length, err, i;
495         unsigned char newChannel;
496         int status;
497         int twoints[2];
498         int retval = 0;
499
500         mutex_lock (&usblp->mut);
501         if (!usblp->present) {
502                 retval = -ENODEV;
503                 goto done;
504         }
505
506         if (usblp->sleeping) {
507                 retval = -ENODEV;
508                 goto done;
509         }
510
511         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
512                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
513
514         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
515
516                 switch (_IOC_NR(cmd)) {
517
518                         case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
519                                 if (_IOC_DIR(cmd) != _IOC_READ) {
520                                         retval = -EINVAL;
521                                         goto done;
522                                 }
523
524                                 length = usblp_cache_device_id_string(usblp);
525                                 if (length < 0) {
526                                         retval = length;
527                                         goto done;
528                                 }
529                                 if (length > _IOC_SIZE(cmd))
530                                         length = _IOC_SIZE(cmd); /* truncate */
531
532                                 if (copy_to_user((void __user *) arg,
533                                                 usblp->device_id_string,
534                                                 (unsigned long) length)) {
535                                         retval = -EFAULT;
536                                         goto done;
537                                 }
538
539                                 break;
540
541                         case IOCNR_GET_PROTOCOLS:
542                                 if (_IOC_DIR(cmd) != _IOC_READ ||
543                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
544                                         retval = -EINVAL;
545                                         goto done;
546                                 }
547
548                                 twoints[0] = usblp->current_protocol;
549                                 twoints[1] = 0;
550                                 for (i = USBLP_FIRST_PROTOCOL;
551                                      i <= USBLP_LAST_PROTOCOL; i++) {
552                                         if (usblp->protocol[i].alt_setting >= 0)
553                                                 twoints[1] |= (1<<i);
554                                 }
555
556                                 if (copy_to_user((void __user *)arg,
557                                                 (unsigned char *)twoints,
558                                                 sizeof(twoints))) {
559                                         retval = -EFAULT;
560                                         goto done;
561                                 }
562
563                                 break;
564
565                         case IOCNR_SET_PROTOCOL:
566                                 if (_IOC_DIR(cmd) != _IOC_WRITE) {
567                                         retval = -EINVAL;
568                                         goto done;
569                                 }
570
571 #ifdef DEBUG
572                                 if (arg == -10) {
573                                         usblp_dump(usblp);
574                                         break;
575                                 }
576 #endif
577
578                                 usblp_unlink_urbs(usblp);
579                                 retval = usblp_set_protocol(usblp, arg);
580                                 if (retval < 0) {
581                                         usblp_set_protocol(usblp,
582                                                 usblp->current_protocol);
583                                 }
584                                 break;
585
586                         case IOCNR_HP_SET_CHANNEL:
587                                 if (_IOC_DIR(cmd) != _IOC_WRITE ||
588                                     le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
589                                     usblp->quirks & USBLP_QUIRK_BIDIR) {
590                                         retval = -EINVAL;
591                                         goto done;
592                                 }
593
594                                 err = usblp_hp_channel_change_request(usblp,
595                                         arg, &newChannel);
596                                 if (err < 0) {
597                                         dev_err(&usblp->dev->dev,
598                                                 "usblp%d: error = %d setting "
599                                                 "HP channel\n",
600                                                 usblp->minor, err);
601                                         retval = -EIO;
602                                         goto done;
603                                 }
604
605                                 dbg("usblp%d requested/got HP channel %ld/%d",
606                                         usblp->minor, arg, newChannel);
607                                 break;
608
609                         case IOCNR_GET_BUS_ADDRESS:
610                                 if (_IOC_DIR(cmd) != _IOC_READ ||
611                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
612                                         retval = -EINVAL;
613                                         goto done;
614                                 }
615
616                                 twoints[0] = usblp->dev->bus->busnum;
617                                 twoints[1] = usblp->dev->devnum;
618                                 if (copy_to_user((void __user *)arg,
619                                                 (unsigned char *)twoints,
620                                                 sizeof(twoints))) {
621                                         retval = -EFAULT;
622                                         goto done;
623                                 }
624
625                                 dbg("usblp%d is bus=%d, device=%d",
626                                         usblp->minor, twoints[0], twoints[1]);
627                                 break;
628
629                         case IOCNR_GET_VID_PID:
630                                 if (_IOC_DIR(cmd) != _IOC_READ ||
631                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
632                                         retval = -EINVAL;
633                                         goto done;
634                                 }
635
636                                 twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
637                                 twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
638                                 if (copy_to_user((void __user *)arg,
639                                                 (unsigned char *)twoints,
640                                                 sizeof(twoints))) {
641                                         retval = -EFAULT;
642                                         goto done;
643                                 }
644
645                                 dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
646                                         usblp->minor, twoints[0], twoints[1]);
647                                 break;
648
649                         case IOCNR_SOFT_RESET:
650                                 if (_IOC_DIR(cmd) != _IOC_NONE) {
651                                         retval = -EINVAL;
652                                         goto done;
653                                 }
654                                 retval = usblp_reset(usblp);
655                                 break;
656                         default:
657                                 retval = -ENOTTY;
658                 }
659         else    /* old-style ioctl value */
660                 switch (cmd) {
661
662                         case LPGETSTATUS:
663                                 if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
664                                         if (printk_ratelimit())
665                                                 printk(KERN_ERR "usblp%d:"
666                                                     "failed reading printer status (%d)\n",
667                                                     usblp->minor, retval);
668                                         retval = -EIO;
669                                         goto done;
670                                 }
671                                 status = *usblp->statusbuf;
672                                 if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
673                                         retval = -EFAULT;
674                                 break;
675
676                         case LPABORT:
677                                 if (arg)
678                                         usblp->flags |= LP_ABORT;
679                                 else
680                                         usblp->flags &= ~LP_ABORT;
681                                 break;
682
683                         default:
684                                 retval = -ENOTTY;
685                 }
686
687 done:
688         mutex_unlock (&usblp->mut);
689         return retval;
690 }
691
692 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
693 {
694         struct urb *urb;
695         char *writebuf;
696
697         if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
698                 return NULL;
699         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
700                 kfree(writebuf);
701                 return NULL;
702         }
703
704         usb_fill_bulk_urb(urb, usblp->dev,
705                 usb_sndbulkpipe(usblp->dev,
706                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
707                 writebuf, transfer_length, usblp_bulk_write, usblp);
708         urb->transfer_flags |= URB_FREE_BUFFER;
709
710         return urb;
711 }
712
713 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
714 {
715         struct usblp *usblp = file->private_data;
716         struct urb *writeurb;
717         int rv;
718         int transfer_length;
719         ssize_t writecount = 0;
720
721         if (mutex_lock_interruptible(&usblp->wmut)) {
722                 rv = -EINTR;
723                 goto raise_biglock;
724         }
725         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
726                 goto raise_wait;
727
728         while (writecount < count) {
729                 /*
730                  * Step 1: Submit next block.
731                  */
732                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
733                         transfer_length = USBLP_BUF_SIZE;
734
735                 rv = -ENOMEM;
736                 if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
737                         goto raise_urb;
738                 usb_anchor_urb(writeurb, &usblp->urbs);
739
740                 if (copy_from_user(writeurb->transfer_buffer,
741                                    buffer + writecount, transfer_length)) {
742                         rv = -EFAULT;
743                         goto raise_badaddr;
744                 }
745
746                 spin_lock_irq(&usblp->lock);
747                 usblp->wcomplete = 0;
748                 spin_unlock_irq(&usblp->lock);
749                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
750                         usblp->wstatus = 0;
751                         spin_lock_irq(&usblp->lock);
752                         usblp->no_paper = 0;
753                         usblp->wcomplete = 1;
754                         wake_up(&usblp->wwait);
755                         spin_unlock_irq(&usblp->lock);
756                         if (rv != -ENOMEM)
757                                 rv = -EIO;
758                         goto raise_submit;
759                 }
760
761                 /*
762                  * Step 2: Wait for transfer to end, collect results.
763                  */
764                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
765                 if (rv < 0) {
766                         if (rv == -EAGAIN) {
767                                 /* Presume that it's going to complete well. */
768                                 writecount += transfer_length;
769                         }
770                         if (rv == -ENOSPC) {
771                                 spin_lock_irq(&usblp->lock);
772                                 usblp->no_paper = 1;    /* Mark for poll(2) */
773                                 spin_unlock_irq(&usblp->lock);
774                                 writecount += transfer_length;
775                         }
776                         /* Leave URB dangling, to be cleaned on close. */
777                         goto collect_error;
778                 }
779
780                 if (usblp->wstatus < 0) {
781                         rv = -EIO;
782                         goto collect_error;
783                 }
784                 /*
785                  * This is critical: it must be our URB, not other writer's.
786                  * The wmut exists mainly to cover us here.
787                  */
788                 writecount += usblp->wstatus;
789         }
790
791         mutex_unlock(&usblp->wmut);
792         return writecount;
793
794 raise_submit:
795 raise_badaddr:
796         usb_unanchor_urb(writeurb);
797         usb_free_urb(writeurb);
798 raise_urb:
799 raise_wait:
800 collect_error:          /* Out of raise sequence */
801         mutex_unlock(&usblp->wmut);
802 raise_biglock:
803         return writecount ? writecount : rv;
804 }
805
806 /*
807  * Notice that we fail to restart in a few cases: on EFAULT, on restart
808  * error, etc. This is the historical behaviour. In all such cases we return
809  * EIO, and applications loop in order to get the new read going.
810  */
811 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
812 {
813         struct usblp *usblp = file->private_data;
814         ssize_t count;
815         ssize_t avail;
816         int rv;
817
818         if (!usblp->bidir)
819                 return -EINVAL;
820
821         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
822         if (rv < 0)
823                 return rv;
824
825         if ((avail = usblp->rstatus) < 0) {
826                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
827                     usblp->minor, (int)avail);
828                 usblp_submit_read(usblp);
829                 count = -EIO;
830                 goto done;
831         }
832
833         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
834         if (count != 0 &&
835             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
836                 count = -EFAULT;
837                 goto done;
838         }
839
840         if ((usblp->readcount += count) == avail) {
841                 if (usblp_submit_read(usblp) < 0) {
842                         /* We don't want to leak USB return codes into errno. */
843                         if (count == 0)
844                                 count = -EIO;
845                         goto done;
846                 }
847         }
848
849 done:
850         mutex_unlock (&usblp->mut);
851         return count;
852 }
853
854 /*
855  * Wait for the write path to come idle.
856  * This is called under the ->wmut, so the idle path stays idle.
857  *
858  * Our write path has a peculiar property: it does not buffer like a tty,
859  * but waits for the write to succeed. This allows our ->release to bug out
860  * without waiting for writes to drain. But it obviously does not work
861  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
862  * select(2) or poll(2) to wait for the buffer to drain before closing.
863  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
864  */
865 static int usblp_wwait(struct usblp *usblp, int nonblock)
866 {
867         DECLARE_WAITQUEUE(waita, current);
868         int rc;
869         int err = 0;
870
871         add_wait_queue(&usblp->wwait, &waita);
872         for (;;) {
873                 set_current_state(TASK_INTERRUPTIBLE);
874                 if (mutex_lock_interruptible(&usblp->mut)) {
875                         rc = -EINTR;
876                         break;
877                 }
878                 rc = usblp_wtest(usblp, nonblock);
879                 mutex_unlock(&usblp->mut);
880                 if (rc <= 0)
881                         break;
882
883                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
884                         if (usblp->flags & LP_ABORT) {
885                                 err = usblp_check_status(usblp, err);
886                                 if (err == 1) { /* Paper out */
887                                         rc = -ENOSPC;
888                                         break;
889                                 }
890                         } else {
891                                 /* Prod the printer, Gentoo#251237. */
892                                 mutex_lock(&usblp->mut);
893                                 usblp_read_status(usblp, usblp->statusbuf);
894                                 mutex_unlock(&usblp->mut);
895                         }
896                 }
897         }
898         set_current_state(TASK_RUNNING);
899         remove_wait_queue(&usblp->wwait, &waita);
900         return rc;
901 }
902
903 static int usblp_wtest(struct usblp *usblp, int nonblock)
904 {
905         unsigned long flags;
906
907         if (!usblp->present)
908                 return -ENODEV;
909         if (signal_pending(current))
910                 return -EINTR;
911         spin_lock_irqsave(&usblp->lock, flags);
912         if (usblp->wcomplete) {
913                 spin_unlock_irqrestore(&usblp->lock, flags);
914                 return 0;
915         }
916         spin_unlock_irqrestore(&usblp->lock, flags);
917         if (usblp->sleeping)
918                 return -ENODEV;
919         if (nonblock)
920                 return -EAGAIN;
921         return 1;
922 }
923
924 /*
925  * Wait for read bytes to become available. This probably should have been
926  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
927  * name for functions which lock and return.
928  *
929  * We do not use wait_event_interruptible because it makes locking iffy.
930  */
931 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
932 {
933         DECLARE_WAITQUEUE(waita, current);
934         int rc;
935
936         add_wait_queue(&usblp->rwait, &waita);
937         for (;;) {
938                 if (mutex_lock_interruptible(&usblp->mut)) {
939                         rc = -EINTR;
940                         break;
941                 }
942                 set_current_state(TASK_INTERRUPTIBLE);
943                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
944                         mutex_unlock(&usblp->mut);
945                         break;
946                 }
947                 if (rc == 0)    /* Keep it locked */
948                         break;
949                 mutex_unlock(&usblp->mut);
950                 schedule();
951         }
952         set_current_state(TASK_RUNNING);
953         remove_wait_queue(&usblp->rwait, &waita);
954         return rc;
955 }
956
957 static int usblp_rtest(struct usblp *usblp, int nonblock)
958 {
959         unsigned long flags;
960
961         if (!usblp->present)
962                 return -ENODEV;
963         if (signal_pending(current))
964                 return -EINTR;
965         spin_lock_irqsave(&usblp->lock, flags);
966         if (usblp->rcomplete) {
967                 spin_unlock_irqrestore(&usblp->lock, flags);
968                 return 0;
969         }
970         spin_unlock_irqrestore(&usblp->lock, flags);
971         if (usblp->sleeping)
972                 return -ENODEV;
973         if (nonblock)
974                 return -EAGAIN;
975         return 1;
976 }
977
978 /*
979  * Please check ->bidir and other such things outside for now.
980  */
981 static int usblp_submit_read(struct usblp *usblp)
982 {
983         struct urb *urb;
984         unsigned long flags;
985         int rc;
986
987         rc = -ENOMEM;
988         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
989                 goto raise_urb;
990
991         usb_fill_bulk_urb(urb, usblp->dev,
992                 usb_rcvbulkpipe(usblp->dev,
993                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
994                 usblp->readbuf, USBLP_BUF_SIZE_IN,
995                 usblp_bulk_read, usblp);
996         usb_anchor_urb(urb, &usblp->urbs);
997
998         spin_lock_irqsave(&usblp->lock, flags);
999         usblp->readcount = 0; /* XXX Why here? */
1000         usblp->rcomplete = 0;
1001         spin_unlock_irqrestore(&usblp->lock, flags);
1002         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1003                 dbg("error submitting urb (%d)", rc);
1004                 spin_lock_irqsave(&usblp->lock, flags);
1005                 usblp->rstatus = rc;
1006                 usblp->rcomplete = 1;
1007                 spin_unlock_irqrestore(&usblp->lock, flags);
1008                 goto raise_submit;
1009         }
1010
1011         return 0;
1012
1013 raise_submit:
1014         usb_unanchor_urb(urb);
1015         usb_free_urb(urb);
1016 raise_urb:
1017         return rc;
1018 }
1019
1020 /*
1021  * Checks for printers that have quirks, such as requiring unidirectional
1022  * communication but reporting bidirectional; currently some HP printers
1023  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1024  * sent at each open (like some Epsons).
1025  * Returns 1 if found, 0 if not found.
1026  *
1027  * HP recommended that we use the bidirectional interface but
1028  * don't attempt any bulk IN transfers from the IN endpoint.
1029  * Here's some more detail on the problem:
1030  * The problem is not that it isn't bidirectional though. The problem
1031  * is that if you request a device ID, or status information, while
1032  * the buffers are full, the return data will end up in the print data
1033  * buffer. For example if you make sure you never request the device ID
1034  * while you are sending print data, and you don't try to query the
1035  * printer status every couple of milliseconds, you will probably be OK.
1036  */
1037 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
1038 {
1039         int i;
1040
1041         for (i = 0; quirk_printers[i].vendorId; i++) {
1042                 if (vendor == quirk_printers[i].vendorId &&
1043                     product == quirk_printers[i].productId)
1044                         return quirk_printers[i].quirks;
1045         }
1046         return 0;
1047 }
1048
1049 static const struct file_operations usblp_fops = {
1050         .owner =        THIS_MODULE,
1051         .read =         usblp_read,
1052         .write =        usblp_write,
1053         .poll =         usblp_poll,
1054         .unlocked_ioctl =       usblp_ioctl,
1055         .compat_ioctl =         usblp_ioctl,
1056         .open =         usblp_open,
1057         .release =      usblp_release,
1058 };
1059
1060 static struct usb_class_driver usblp_class = {
1061         .name =         "lp%d",
1062         .fops =         &usblp_fops,
1063         .minor_base =   USBLP_MINOR_BASE,
1064 };
1065
1066 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1067 {
1068         struct usb_interface *intf = to_usb_interface(dev);
1069         struct usblp *usblp = usb_get_intfdata (intf);
1070
1071         if (usblp->device_id_string[0] == 0 &&
1072             usblp->device_id_string[1] == 0)
1073                 return 0;
1074
1075         return sprintf(buf, "%s", usblp->device_id_string+2);
1076 }
1077
1078 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1079
1080 static int usblp_probe(struct usb_interface *intf,
1081                        const struct usb_device_id *id)
1082 {
1083         struct usb_device *dev = interface_to_usbdev (intf);
1084         struct usblp *usblp;
1085         int protocol;
1086         int retval;
1087
1088         /* Malloc and start initializing usblp structure so we can use it
1089          * directly. */
1090         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1091         if (!usblp) {
1092                 retval = -ENOMEM;
1093                 goto abort_ret;
1094         }
1095         usblp->dev = dev;
1096         mutex_init(&usblp->wmut);
1097         mutex_init (&usblp->mut);
1098         spin_lock_init(&usblp->lock);
1099         init_waitqueue_head(&usblp->rwait);
1100         init_waitqueue_head(&usblp->wwait);
1101         init_usb_anchor(&usblp->urbs);
1102         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1103         usblp->intf = intf;
1104
1105         /* Malloc device ID string buffer to the largest expected length,
1106          * since we can re-query it on an ioctl and a dynamic string
1107          * could change in length. */
1108         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1109                 retval = -ENOMEM;
1110                 goto abort;
1111         }
1112
1113         /*
1114          * Allocate read buffer. We somewhat wastefully
1115          * malloc both regardless of bidirectionality, because the
1116          * alternate setting can be changed later via an ioctl.
1117          */
1118         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1119                 retval = -ENOMEM;
1120                 goto abort;
1121         }
1122
1123         /* Allocate buffer for printer status */
1124         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1125         if (!usblp->statusbuf) {
1126                 retval = -ENOMEM;
1127                 goto abort;
1128         }
1129
1130         /* Lookup quirks for this printer. */
1131         usblp->quirks = usblp_quirks(
1132                 le16_to_cpu(dev->descriptor.idVendor),
1133                 le16_to_cpu(dev->descriptor.idProduct));
1134
1135         /* Analyze and pick initial alternate settings and endpoints. */
1136         protocol = usblp_select_alts(usblp);
1137         if (protocol < 0) {
1138                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
1139                         le16_to_cpu(dev->descriptor.idVendor),
1140                         le16_to_cpu(dev->descriptor.idProduct));
1141                 retval = -ENODEV;
1142                 goto abort;
1143         }
1144
1145         /* Setup the selected alternate setting and endpoints. */
1146         if (usblp_set_protocol(usblp, protocol) < 0) {
1147                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1148                 goto abort;
1149         }
1150
1151         /* Retrieve and store the device ID string. */
1152         usblp_cache_device_id_string(usblp);
1153         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1154         if (retval)
1155                 goto abort_intfdata;
1156
1157 #ifdef DEBUG
1158         usblp_check_status(usblp, 0);
1159 #endif
1160
1161         usb_set_intfdata (intf, usblp);
1162
1163         usblp->present = 1;
1164
1165         retval = usb_register_dev(intf, &usblp_class);
1166         if (retval) {
1167                 printk(KERN_ERR "usblp: Not able to get a minor"
1168                     " (base %u, slice default): %d\n",
1169                     USBLP_MINOR_BASE, retval);
1170                 goto abort_intfdata;
1171         }
1172         usblp->minor = intf->minor;
1173         printk(KERN_INFO "usblp%d: USB %sdirectional printer dev %d "
1174                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1175                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1176                 usblp->ifnum,
1177                 usblp->protocol[usblp->current_protocol].alt_setting,
1178                 usblp->current_protocol,
1179                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1180                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1181
1182         return 0;
1183
1184 abort_intfdata:
1185         usb_set_intfdata (intf, NULL);
1186         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1187 abort:
1188         kfree(usblp->readbuf);
1189         kfree(usblp->statusbuf);
1190         kfree(usblp->device_id_string);
1191         kfree(usblp);
1192 abort_ret:
1193         return retval;
1194 }
1195
1196 /*
1197  * We are a "new" style driver with usb_device_id table,
1198  * but our requirements are too intricate for simple match to handle.
1199  *
1200  * The "proto_bias" option may be used to specify the preferred protocol
1201  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1202  * supports the preferred protocol, then we bind to it.
1203  *
1204  * The best interface for us is 7/1/2, because it is compatible
1205  * with a stream of characters. If we find it, we bind to it.
1206  *
1207  * Note that the people from hpoj.sourceforge.net need to be able to
1208  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1209  *
1210  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1211  * stream-compatible, because this matches the behaviour of the old code.
1212  *
1213  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1214  */
1215 static int usblp_select_alts(struct usblp *usblp)
1216 {
1217         struct usb_interface *if_alt;
1218         struct usb_host_interface *ifd;
1219         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1220         int p, i, e;
1221
1222         if_alt = usblp->intf;
1223
1224         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1225                 usblp->protocol[p].alt_setting = -1;
1226
1227         /* Find out what we have. */
1228         for (i = 0; i < if_alt->num_altsetting; i++) {
1229                 ifd = &if_alt->altsetting[i];
1230
1231                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1232                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1233                                 continue;
1234
1235                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1236                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1237                         continue;
1238
1239                 /* Look for bulk OUT and IN endpoints. */
1240                 epwrite = epread = NULL;
1241                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1242                         epd = &ifd->endpoint[e].desc;
1243
1244                         if (usb_endpoint_is_bulk_out(epd))
1245                                 if (!epwrite)
1246                                         epwrite = epd;
1247
1248                         if (usb_endpoint_is_bulk_in(epd))
1249                                 if (!epread)
1250                                         epread = epd;
1251                 }
1252
1253                 /* Ignore buggy hardware without the right endpoints. */
1254                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1255                         continue;
1256
1257                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1258                  * and buggy bidirectional printers. */
1259                 if (ifd->desc.bInterfaceProtocol == 1) {
1260                         epread = NULL;
1261                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1262                         printk(KERN_INFO "usblp%d: Disabling reads from "
1263                             "problematic bidirectional printer\n",
1264                             usblp->minor);
1265                         epread = NULL;
1266                 }
1267
1268                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1269                                 ifd->desc.bAlternateSetting;
1270                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1271                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1272         }
1273
1274         /* If our requested protocol is supported, then use it. */
1275         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1276             proto_bias <= USBLP_LAST_PROTOCOL &&
1277             usblp->protocol[proto_bias].alt_setting != -1)
1278                 return proto_bias;
1279
1280         /* Ordering is important here. */
1281         if (usblp->protocol[2].alt_setting != -1)
1282                 return 2;
1283         if (usblp->protocol[1].alt_setting != -1)
1284                 return 1;
1285         if (usblp->protocol[3].alt_setting != -1)
1286                 return 3;
1287
1288         /* If nothing is available, then don't bind to this device. */
1289         return -1;
1290 }
1291
1292 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1293 {
1294         int r, alts;
1295
1296         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1297                 return -EINVAL;
1298
1299         alts = usblp->protocol[protocol].alt_setting;
1300         if (alts < 0)
1301                 return -EINVAL;
1302         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1303         if (r < 0) {
1304                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1305                         alts, usblp->ifnum);
1306                 return r;
1307         }
1308
1309         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1310         usblp->current_protocol = protocol;
1311         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1312         return 0;
1313 }
1314
1315 /* Retrieves and caches device ID string.
1316  * Returns length, including length bytes but not null terminator.
1317  * On error, returns a negative errno value. */
1318 static int usblp_cache_device_id_string(struct usblp *usblp)
1319 {
1320         int err, length;
1321
1322         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1323         if (err < 0) {
1324                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1325                         usblp->minor, err);
1326                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1327                 return -EIO;
1328         }
1329
1330         /* First two bytes are length in big-endian.
1331          * They count themselves, and we copy them into
1332          * the user's buffer. */
1333         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1334         if (length < 2)
1335                 length = 2;
1336         else if (length >= USBLP_DEVICE_ID_SIZE)
1337                 length = USBLP_DEVICE_ID_SIZE - 1;
1338         usblp->device_id_string[length] = '\0';
1339
1340         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1341                 usblp->minor, length, &usblp->device_id_string[2]);
1342
1343         return length;
1344 }
1345
1346 static void usblp_disconnect(struct usb_interface *intf)
1347 {
1348         struct usblp *usblp = usb_get_intfdata (intf);
1349
1350         usb_deregister_dev(intf, &usblp_class);
1351
1352         if (!usblp || !usblp->dev) {
1353                 dev_err(&intf->dev, "bogus disconnect\n");
1354                 BUG ();
1355         }
1356
1357         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1358
1359         mutex_lock (&usblp_mutex);
1360         mutex_lock (&usblp->mut);
1361         usblp->present = 0;
1362         wake_up(&usblp->wwait);
1363         wake_up(&usblp->rwait);
1364         usb_set_intfdata (intf, NULL);
1365
1366         usblp_unlink_urbs(usblp);
1367         mutex_unlock (&usblp->mut);
1368
1369         if (!usblp->used)
1370                 usblp_cleanup (usblp);
1371         mutex_unlock (&usblp_mutex);
1372 }
1373
1374 static int usblp_suspend (struct usb_interface *intf, pm_message_t message)
1375 {
1376         struct usblp *usblp = usb_get_intfdata (intf);
1377
1378         /* we take no more IO */
1379         usblp->sleeping = 1;
1380         usblp_unlink_urbs(usblp);
1381 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1382         /* not strictly necessary, but just in case */
1383         wake_up(&usblp->wwait);
1384         wake_up(&usblp->rwait);
1385 #endif
1386
1387         return 0;
1388 }
1389
1390 static int usblp_resume (struct usb_interface *intf)
1391 {
1392         struct usblp *usblp = usb_get_intfdata (intf);
1393         int r;
1394
1395         usblp->sleeping = 0;
1396         r = handle_bidir (usblp);
1397
1398         return r;
1399 }
1400
1401 static struct usb_device_id usblp_ids [] = {
1402         { USB_DEVICE_INFO(7, 1, 1) },
1403         { USB_DEVICE_INFO(7, 1, 2) },
1404         { USB_DEVICE_INFO(7, 1, 3) },
1405         { USB_INTERFACE_INFO(7, 1, 1) },
1406         { USB_INTERFACE_INFO(7, 1, 2) },
1407         { USB_INTERFACE_INFO(7, 1, 3) },
1408         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1409         { }                                             /* Terminating entry */
1410 };
1411
1412 MODULE_DEVICE_TABLE (usb, usblp_ids);
1413
1414 static struct usb_driver usblp_driver = {
1415         .name =         "usblp",
1416         .probe =        usblp_probe,
1417         .disconnect =   usblp_disconnect,
1418         .suspend =      usblp_suspend,
1419         .resume =       usblp_resume,
1420         .id_table =     usblp_ids,
1421         .supports_autosuspend = 1,
1422 };
1423
1424 static int __init usblp_init(void)
1425 {
1426         return usb_register(&usblp_driver);
1427 }
1428
1429 static void __exit usblp_exit(void)
1430 {
1431         usb_deregister(&usblp_driver);
1432 }
1433
1434 module_init(usblp_init);
1435 module_exit(usblp_exit);
1436
1437 MODULE_AUTHOR( DRIVER_AUTHOR );
1438 MODULE_DESCRIPTION( DRIVER_DESC );
1439 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1440 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1441 MODULE_LICENSE("GPL");