usblp: mutex in usblp_check_status
[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  */
32
33 /*
34  * This program is free software; you can redistribute it and/or modify
35  * it under the terms of the GNU General Public License as published by
36  * the Free Software Foundation; either version 2 of the License, or
37  * (at your option) any later version.
38  *
39  * This program is distributed in the hope that it will be useful,
40  * but WITHOUT ANY WARRANTY; without even the implied warranty of
41  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
42  * GNU General Public License for more details.
43  *
44  * You should have received a copy of the GNU General Public License
45  * along with this program; if not, write to the Free Software
46  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
47  */
48
49 #include <linux/module.h>
50 #include <linux/kernel.h>
51 #include <linux/sched.h>
52 #include <linux/signal.h>
53 #include <linux/poll.h>
54 #include <linux/init.h>
55 #include <linux/slab.h>
56 #include <linux/lp.h>
57 #include <linux/mutex.h>
58 #undef DEBUG
59 #include <linux/usb.h>
60
61 /*
62  * Version Information
63  */
64 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
65 #define DRIVER_DESC "USB Printer Device Class driver"
66
67 #define USBLP_BUF_SIZE          8192
68 #define USBLP_BUF_SIZE_IN       1024
69 #define USBLP_DEVICE_ID_SIZE    1024
70
71 /* ioctls: */
72 #define IOCNR_GET_DEVICE_ID             1
73 #define IOCNR_GET_PROTOCOLS             2
74 #define IOCNR_SET_PROTOCOL              3
75 #define IOCNR_HP_SET_CHANNEL            4
76 #define IOCNR_GET_BUS_ADDRESS           5
77 #define IOCNR_GET_VID_PID               6
78 #define IOCNR_SOFT_RESET                7
79 /* Get device_id string: */
80 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
81 /* The following ioctls were added for http://hpoj.sourceforge.net: */
82 /* Get two-int array:
83  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
84  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
85 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
86 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
87 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
88 /* Set channel number (HP Vendor-specific command): */
89 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
90 /* Get two-int array: [0]=bus number, [1]=device address: */
91 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
92 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
93 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
94 /* Perform class specific soft reset */
95 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
96
97 /*
98  * A DEVICE_ID string may include the printer's serial number.
99  * It should end with a semi-colon (';').
100  * An example from an HP 970C DeskJet printer is (this is one long string,
101  * with the serial number changed):
102 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
103  */
104
105 /*
106  * USB Printer Requests
107  */
108
109 #define USBLP_REQ_GET_ID                        0x00
110 #define USBLP_REQ_GET_STATUS                    0x01
111 #define USBLP_REQ_RESET                         0x02
112 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
113
114 #define USBLP_MINORS            16
115 #define USBLP_MINOR_BASE        0
116
117 #define USBLP_WRITE_TIMEOUT     (5000)                  /* 5 seconds */
118
119 #define USBLP_FIRST_PROTOCOL    1
120 #define USBLP_LAST_PROTOCOL     3
121 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
122
123 /*
124  * some arbitrary status buffer size;
125  * need a status buffer that is allocated via kmalloc(), not on stack
126  */
127 #define STATUS_BUF_SIZE         8
128
129 /*
130  * Locks down the locking order:
131  * ->wmut locks wstatus.
132  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
133  * [rw]status. We only touch status when we know the side idle.
134  * ->lock locks what interrupt accesses.
135  */
136 struct usblp {
137         struct usb_device       *dev;                   /* USB device */
138         struct mutex            wmut;
139         struct mutex            mut;
140         spinlock_t              lock;           /* locks rcomplete, wcomplete */
141         char                    *readbuf;               /* read transfer_buffer */
142         char                    *statusbuf;             /* status transfer_buffer */
143         struct usb_anchor       urbs;
144         wait_queue_head_t       rwait, wwait;
145         int                     readcount;              /* Counter for reads */
146         int                     ifnum;                  /* Interface number */
147         struct usb_interface    *intf;                  /* The interface */
148         /* Alternate-setting numbers and endpoints for each protocol
149          * (7/1/{index=1,2,3}) that the device supports: */
150         struct {
151                 int                             alt_setting;
152                 struct usb_endpoint_descriptor  *epwrite;
153                 struct usb_endpoint_descriptor  *epread;
154         }                       protocol[USBLP_MAX_PROTOCOLS];
155         int                     current_protocol;
156         int                     minor;                  /* minor number of device */
157         int                     wcomplete, rcomplete;
158         int                     wstatus;        /* bytes written or error */
159         int                     rstatus;        /* bytes ready or error */
160         unsigned int            quirks;                 /* quirks flags */
161         unsigned int            flags;                  /* mode flags */
162         unsigned char           used;                   /* True if open */
163         unsigned char           present;                /* True if not disconnected */
164         unsigned char           bidir;                  /* interface is bidirectional */
165         unsigned char           sleeping;               /* interface is suspended */
166         unsigned char           no_paper;               /* Paper Out happened */
167         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
168                                                         /* first 2 bytes are (big-endian) length */
169 };
170
171 #ifdef DEBUG
172 static void usblp_dump(struct usblp *usblp) {
173         int p;
174
175         dbg("usblp=0x%p", usblp);
176         dbg("dev=0x%p", usblp->dev);
177         dbg("present=%d", usblp->present);
178         dbg("readbuf=0x%p", usblp->readbuf);
179         dbg("readcount=%d", usblp->readcount);
180         dbg("ifnum=%d", usblp->ifnum);
181     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
182         dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
183         dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
184         dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
185     }
186         dbg("current_protocol=%d", usblp->current_protocol);
187         dbg("minor=%d", usblp->minor);
188         dbg("wstatus=%d", usblp->wstatus);
189         dbg("rstatus=%d", usblp->rstatus);
190         dbg("quirks=%d", usblp->quirks);
191         dbg("used=%d", usblp->used);
192         dbg("bidir=%d", usblp->bidir);
193         dbg("sleeping=%d", usblp->sleeping);
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         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
229         { 0, 0 }
230 };
231
232 static int usblp_wwait(struct usblp *usblp, int nonblock);
233 static int usblp_wtest(struct usblp *usblp, int nonblock);
234 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
235 static int usblp_rtest(struct usblp *usblp, int nonblock);
236 static int usblp_submit_read(struct usblp *usblp);
237 static int usblp_select_alts(struct usblp *usblp);
238 static int usblp_set_protocol(struct usblp *usblp, int protocol);
239 static int usblp_cache_device_id_string(struct usblp *usblp);
240
241 /* forward reference to make our lives easier */
242 static struct usb_driver usblp_driver;
243 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
244
245 /*
246  * Functions for usblp control messages.
247  */
248
249 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
250 {
251         int retval;
252         int index = usblp->ifnum;
253
254         /* High byte has the interface index.
255            Low byte has the alternate setting.
256          */
257         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
258           index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
259         }
260
261         retval = usb_control_msg(usblp->dev,
262                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
263                 request, type | dir | recip, value, index, buf, len, USBLP_WRITE_TIMEOUT);
264         dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
265                 request, !!dir, recip, value, index, len, retval);
266         return retval < 0 ? retval : 0;
267 }
268
269 #define usblp_read_status(usblp, status)\
270         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
271 #define usblp_get_id(usblp, config, id, maxlen)\
272         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
273 #define usblp_reset(usblp)\
274         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
275
276 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
277         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
278
279 /*
280  * See the description for usblp_select_alts() below for the usage
281  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
282  * case of any trouble.
283  */
284 static int proto_bias = -1;
285
286 /*
287  * URB callback.
288  */
289
290 static void usblp_bulk_read(struct urb *urb)
291 {
292         struct usblp *usblp = urb->context;
293         int status = urb->status;
294
295         if (usblp->present && usblp->used) {
296                 if (status)
297                         printk(KERN_WARNING "usblp%d: "
298                             "nonzero read bulk status received: %d\n",
299                             usblp->minor, status);
300         }
301         spin_lock(&usblp->lock);
302         if (status < 0)
303                 usblp->rstatus = status;
304         else
305                 usblp->rstatus = urb->actual_length;
306         usblp->rcomplete = 1;
307         wake_up(&usblp->rwait);
308         spin_unlock(&usblp->lock);
309
310         usb_free_urb(urb);
311 }
312
313 static void usblp_bulk_write(struct urb *urb)
314 {
315         struct usblp *usblp = urb->context;
316         int status = urb->status;
317
318         if (usblp->present && usblp->used) {
319                 if (status)
320                         printk(KERN_WARNING "usblp%d: "
321                             "nonzero write bulk status received: %d\n",
322                             usblp->minor, status);
323         }
324         spin_lock(&usblp->lock);
325         if (status < 0)
326                 usblp->wstatus = status;
327         else
328                 usblp->wstatus = urb->actual_length;
329         usblp->no_paper = 0;
330         usblp->wcomplete = 1;
331         wake_up(&usblp->wwait);
332         spin_unlock(&usblp->lock);
333
334         usb_free_urb(urb);
335 }
336
337 /*
338  * Get and print printer errors.
339  */
340
341 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
342
343 static int usblp_check_status(struct usblp *usblp, int err)
344 {
345         unsigned char status, newerr = 0;
346         int error;
347
348         mutex_lock(&usblp->mut);
349         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
350                 mutex_unlock(&usblp->mut);
351                 if (printk_ratelimit())
352                         printk(KERN_ERR
353                                 "usblp%d: error %d reading printer status\n",
354                                 usblp->minor, error);
355                 return 0;
356         }
357         status = *usblp->statusbuf;
358         mutex_unlock(&usblp->mut);
359
360         if (~status & LP_PERRORP)
361                 newerr = 3;
362         if (status & LP_POUTPA)
363                 newerr = 1;
364         if (~status & LP_PSELECD)
365                 newerr = 2;
366
367         if (newerr != err) {
368                 printk(KERN_INFO "usblp%d: %s\n",
369                    usblp->minor, usblp_messages[newerr]);
370         }
371
372         return newerr;
373 }
374
375 static int handle_bidir (struct usblp *usblp)
376 {
377         if (usblp->bidir && usblp->used && !usblp->sleeping) {
378                 if (usblp_submit_read(usblp) < 0)
379                         return -EIO;
380         }
381         return 0;
382 }
383
384 /*
385  * File op functions.
386  */
387
388 static int usblp_open(struct inode *inode, struct file *file)
389 {
390         int minor = iminor(inode);
391         struct usblp *usblp;
392         struct usb_interface *intf;
393         int retval;
394
395         if (minor < 0)
396                 return -ENODEV;
397
398         mutex_lock (&usblp_mutex);
399
400         retval = -ENODEV;
401         intf = usb_find_interface(&usblp_driver, minor);
402         if (!intf) {
403                 goto out;
404         }
405         usblp = usb_get_intfdata (intf);
406         if (!usblp || !usblp->dev || !usblp->present)
407                 goto out;
408
409         retval = -EBUSY;
410         if (usblp->used)
411                 goto out;
412
413         /*
414          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
415          *  - We do not want persistent state which close(2) does not clear
416          *  - It is not used anyway, according to CUPS people
417          */
418
419         retval = usb_autopm_get_interface(intf);
420         if (retval < 0)
421                 goto out;
422         usblp->used = 1;
423         file->private_data = usblp;
424
425         usblp->wcomplete = 1; /* we begin writeable */
426         usblp->wstatus = 0;
427         usblp->rcomplete = 0;
428
429         if (handle_bidir(usblp) < 0) {
430                 usblp->used = 0;
431                 file->private_data = NULL;
432                 retval = -EIO;
433         }
434 out:
435         mutex_unlock (&usblp_mutex);
436         return retval;
437 }
438
439 static void usblp_cleanup (struct usblp *usblp)
440 {
441         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
442
443         kfree(usblp->readbuf);
444         kfree (usblp->device_id_string);
445         kfree (usblp->statusbuf);
446         kfree (usblp);
447 }
448
449 static void usblp_unlink_urbs(struct usblp *usblp)
450 {
451         usb_kill_anchored_urbs(&usblp->urbs);
452 }
453
454 static int usblp_release(struct inode *inode, struct file *file)
455 {
456         struct usblp *usblp = file->private_data;
457
458         usblp->flags &= ~LP_ABORT;
459
460         mutex_lock (&usblp_mutex);
461         usblp->used = 0;
462         if (usblp->present) {
463                 usblp_unlink_urbs(usblp);
464                 usb_autopm_put_interface(usblp->intf);
465         } else          /* finish cleanup from disconnect */
466                 usblp_cleanup (usblp);
467         mutex_unlock (&usblp_mutex);
468         return 0;
469 }
470
471 /* No kernel lock - fine */
472 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
473 {
474         int ret;
475         unsigned long flags;
476
477         struct usblp *usblp = file->private_data;
478         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
479         poll_wait(file, &usblp->rwait, wait);
480         poll_wait(file, &usblp->wwait, wait);
481         spin_lock_irqsave(&usblp->lock, flags);
482         ret = ((!usblp->bidir || !usblp->rcomplete) ? 0 : POLLIN  | POLLRDNORM)
483            | ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
484         spin_unlock_irqrestore(&usblp->lock, flags);
485         return ret;
486 }
487
488 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
489 {
490         struct usblp *usblp = file->private_data;
491         int length, err, i;
492         unsigned char newChannel;
493         int status;
494         int twoints[2];
495         int retval = 0;
496
497         mutex_lock (&usblp->mut);
498         if (!usblp->present) {
499                 retval = -ENODEV;
500                 goto done;
501         }
502
503         if (usblp->sleeping) {
504                 retval = -ENODEV;
505                 goto done;
506         }
507
508         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
509                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
510
511         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
512
513                 switch (_IOC_NR(cmd)) {
514
515                         case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
516                                 if (_IOC_DIR(cmd) != _IOC_READ) {
517                                         retval = -EINVAL;
518                                         goto done;
519                                 }
520
521                                 length = usblp_cache_device_id_string(usblp);
522                                 if (length < 0) {
523                                         retval = length;
524                                         goto done;
525                                 }
526                                 if (length > _IOC_SIZE(cmd))
527                                         length = _IOC_SIZE(cmd); /* truncate */
528
529                                 if (copy_to_user((void __user *) arg,
530                                                 usblp->device_id_string,
531                                                 (unsigned long) length)) {
532                                         retval = -EFAULT;
533                                         goto done;
534                                 }
535
536                                 break;
537
538                         case IOCNR_GET_PROTOCOLS:
539                                 if (_IOC_DIR(cmd) != _IOC_READ ||
540                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
541                                         retval = -EINVAL;
542                                         goto done;
543                                 }
544
545                                 twoints[0] = usblp->current_protocol;
546                                 twoints[1] = 0;
547                                 for (i = USBLP_FIRST_PROTOCOL;
548                                      i <= USBLP_LAST_PROTOCOL; i++) {
549                                         if (usblp->protocol[i].alt_setting >= 0)
550                                                 twoints[1] |= (1<<i);
551                                 }
552
553                                 if (copy_to_user((void __user *)arg,
554                                                 (unsigned char *)twoints,
555                                                 sizeof(twoints))) {
556                                         retval = -EFAULT;
557                                         goto done;
558                                 }
559
560                                 break;
561
562                         case IOCNR_SET_PROTOCOL:
563                                 if (_IOC_DIR(cmd) != _IOC_WRITE) {
564                                         retval = -EINVAL;
565                                         goto done;
566                                 }
567
568 #ifdef DEBUG
569                                 if (arg == -10) {
570                                         usblp_dump(usblp);
571                                         break;
572                                 }
573 #endif
574
575                                 usblp_unlink_urbs(usblp);
576                                 retval = usblp_set_protocol(usblp, arg);
577                                 if (retval < 0) {
578                                         usblp_set_protocol(usblp,
579                                                 usblp->current_protocol);
580                                 }
581                                 break;
582
583                         case IOCNR_HP_SET_CHANNEL:
584                                 if (_IOC_DIR(cmd) != _IOC_WRITE ||
585                                     le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
586                                     usblp->quirks & USBLP_QUIRK_BIDIR) {
587                                         retval = -EINVAL;
588                                         goto done;
589                                 }
590
591                                 err = usblp_hp_channel_change_request(usblp,
592                                         arg, &newChannel);
593                                 if (err < 0) {
594                                         err("usblp%d: error = %d setting "
595                                                 "HP channel",
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 ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
689 {
690         struct usblp *usblp = file->private_data;
691         char *writebuf;
692         struct urb *writeurb;
693         int rv;
694         int transfer_length;
695         ssize_t writecount = 0;
696
697         if (mutex_lock_interruptible(&usblp->wmut)) {
698                 rv = -EINTR;
699                 goto raise_biglock;
700         }
701         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
702                 goto raise_wait;
703
704         while (writecount < count) {
705                 /*
706                  * Step 1: Submit next block.
707                  */
708                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
709                         transfer_length = USBLP_BUF_SIZE;
710
711                 rv = -ENOMEM;
712                 if ((writebuf = kmalloc(USBLP_BUF_SIZE, GFP_KERNEL)) == NULL)
713                         goto raise_buf;
714                 if ((writeurb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
715                         goto raise_urb;
716                 usb_fill_bulk_urb(writeurb, usblp->dev,
717                         usb_sndbulkpipe(usblp->dev,
718                           usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
719                         writebuf, transfer_length, usblp_bulk_write, usblp);
720                 writeurb->transfer_flags |= URB_FREE_BUFFER;
721                 usb_anchor_urb(writeurb, &usblp->urbs);
722
723                 if (copy_from_user(writebuf,
724                                    buffer + writecount, transfer_length)) {
725                         rv = -EFAULT;
726                         goto raise_badaddr;
727                 }
728
729                 spin_lock_irq(&usblp->lock);
730                 usblp->wcomplete = 0;
731                 spin_unlock_irq(&usblp->lock);
732                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
733                         usblp->wstatus = 0;
734                         spin_lock_irq(&usblp->lock);
735                         usblp->no_paper = 0;
736                         usblp->wcomplete = 1;
737                         wake_up(&usblp->wwait);
738                         spin_unlock_irq(&usblp->lock);
739                         if (rv != -ENOMEM)
740                                 rv = -EIO;
741                         goto raise_submit;
742                 }
743
744                 /*
745                  * Step 2: Wait for transfer to end, collect results.
746                  */
747                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
748                 if (rv < 0) {
749                         if (rv == -EAGAIN) {
750                                 /* Presume that it's going to complete well. */
751                                 writecount += transfer_length;
752                         }
753                         if (rv == -ENOSPC) {
754                                 spin_lock_irq(&usblp->lock);
755                                 usblp->no_paper = 1;    /* Mark for poll(2) */
756                                 spin_unlock_irq(&usblp->lock);
757                                 writecount += transfer_length;
758                         }
759                         /* Leave URB dangling, to be cleaned on close. */
760                         goto collect_error;
761                 }
762
763                 if (usblp->wstatus < 0) {
764                         rv = -EIO;
765                         goto collect_error;
766                 }
767                 /*
768                  * This is critical: it must be our URB, not other writer's.
769                  * The wmut exists mainly to cover us here.
770                  */
771                 writecount += usblp->wstatus;
772         }
773
774         mutex_unlock(&usblp->wmut);
775         return writecount;
776
777 raise_submit:
778 raise_badaddr:
779         usb_unanchor_urb(writeurb);
780         usb_free_urb(writeurb);
781 raise_urb:
782         kfree(writebuf);
783 raise_buf:
784 raise_wait:
785 collect_error:          /* Out of raise sequence */
786         mutex_unlock(&usblp->wmut);
787 raise_biglock:
788         return writecount ? writecount : rv;
789 }
790
791 /*
792  * Notice that we fail to restart in a few cases: on EFAULT, on restart
793  * error, etc. This is the historical behaviour. In all such cases we return
794  * EIO, and applications loop in order to get the new read going.
795  */
796 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
797 {
798         struct usblp *usblp = file->private_data;
799         ssize_t count;
800         ssize_t avail;
801         int rv;
802
803         if (!usblp->bidir)
804                 return -EINVAL;
805
806         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
807         if (rv < 0)
808                 return rv;
809
810         if ((avail = usblp->rstatus) < 0) {
811                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
812                     usblp->minor, (int)avail);
813                 usblp_submit_read(usblp);
814                 count = -EIO;
815                 goto done;
816         }
817
818         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
819         if (count != 0 &&
820             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
821                 count = -EFAULT;
822                 goto done;
823         }
824
825         if ((usblp->readcount += count) == avail) {
826                 if (usblp_submit_read(usblp) < 0) {
827                         /* We don't want to leak USB return codes into errno. */
828                         if (count == 0)
829                                 count = -EIO;
830                         goto done;
831                 }
832         }
833
834 done:
835         mutex_unlock (&usblp->mut);
836         return count;
837 }
838
839 /*
840  * Wait for the write path to come idle.
841  * This is called under the ->wmut, so the idle path stays idle.
842  *
843  * Our write path has a peculiar property: it does not buffer like a tty,
844  * but waits for the write to succeed. This allows our ->release to bug out
845  * without waiting for writes to drain. But it obviously does not work
846  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
847  * select(2) or poll(2) to wait for the buffer to drain before closing.
848  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
849  */
850 static int usblp_wwait(struct usblp *usblp, int nonblock)
851 {
852         DECLARE_WAITQUEUE(waita, current);
853         int rc;
854         int err = 0;
855
856         add_wait_queue(&usblp->wwait, &waita);
857         for (;;) {
858                 set_current_state(TASK_INTERRUPTIBLE);
859                 if (mutex_lock_interruptible(&usblp->mut)) {
860                         rc = -EINTR;
861                         break;
862                 }
863                 rc = usblp_wtest(usblp, nonblock);
864                 mutex_unlock(&usblp->mut);
865                 if (rc <= 0)
866                         break;
867
868                 if (usblp->flags & LP_ABORT) {
869                         if (schedule_timeout(msecs_to_jiffies(5000)) == 0) {
870                                 err = usblp_check_status(usblp, err);
871                                 if (err == 1) { /* Paper out */
872                                         rc = -ENOSPC;
873                                         break;
874                                 }
875                         }
876                 } else {
877                         schedule();
878                 }
879         }
880         set_current_state(TASK_RUNNING);
881         remove_wait_queue(&usblp->wwait, &waita);
882         return rc;
883 }
884
885 static int usblp_wtest(struct usblp *usblp, int nonblock)
886 {
887         unsigned long flags;
888
889         if (!usblp->present)
890                 return -ENODEV;
891         if (signal_pending(current))
892                 return -EINTR;
893         spin_lock_irqsave(&usblp->lock, flags);
894         if (usblp->wcomplete) {
895                 spin_unlock_irqrestore(&usblp->lock, flags);
896                 return 0;
897         }
898         spin_unlock_irqrestore(&usblp->lock, flags);
899         if (usblp->sleeping)
900                 return -ENODEV;
901         if (nonblock)
902                 return -EAGAIN;
903         return 1;
904 }
905
906 /*
907  * Wait for read bytes to become available. This probably should have been
908  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
909  * name for functions which lock and return.
910  *
911  * We do not use wait_event_interruptible because it makes locking iffy.
912  */
913 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
914 {
915         DECLARE_WAITQUEUE(waita, current);
916         int rc;
917
918         add_wait_queue(&usblp->rwait, &waita);
919         for (;;) {
920                 if (mutex_lock_interruptible(&usblp->mut)) {
921                         rc = -EINTR;
922                         break;
923                 }
924                 set_current_state(TASK_INTERRUPTIBLE);
925                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
926                         mutex_unlock(&usblp->mut);
927                         break;
928                 }
929                 if (rc == 0)    /* Keep it locked */
930                         break;
931                 mutex_unlock(&usblp->mut);
932                 schedule();
933         }
934         set_current_state(TASK_RUNNING);
935         remove_wait_queue(&usblp->rwait, &waita);
936         return rc;
937 }
938
939 static int usblp_rtest(struct usblp *usblp, int nonblock)
940 {
941         unsigned long flags;
942
943         if (!usblp->present)
944                 return -ENODEV;
945         if (signal_pending(current))
946                 return -EINTR;
947         spin_lock_irqsave(&usblp->lock, flags);
948         if (usblp->rcomplete) {
949                 spin_unlock_irqrestore(&usblp->lock, flags);
950                 return 0;
951         }
952         spin_unlock_irqrestore(&usblp->lock, flags);
953         if (usblp->sleeping)
954                 return -ENODEV;
955         if (nonblock)
956                 return -EAGAIN;
957         return 1;
958 }
959
960 /*
961  * Please check ->bidir and other such things outside for now.
962  */
963 static int usblp_submit_read(struct usblp *usblp)
964 {
965         struct urb *urb;
966         unsigned long flags;
967         int rc;
968
969         rc = -ENOMEM;
970         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
971                 goto raise_urb;
972
973         usb_fill_bulk_urb(urb, usblp->dev,
974                 usb_rcvbulkpipe(usblp->dev,
975                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
976                 usblp->readbuf, USBLP_BUF_SIZE_IN,
977                 usblp_bulk_read, usblp);
978         usb_anchor_urb(urb, &usblp->urbs);
979
980         spin_lock_irqsave(&usblp->lock, flags);
981         usblp->readcount = 0; /* XXX Why here? */
982         usblp->rcomplete = 0;
983         spin_unlock_irqrestore(&usblp->lock, flags);
984         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
985                 dbg("error submitting urb (%d)", rc);
986                 spin_lock_irqsave(&usblp->lock, flags);
987                 usblp->rstatus = rc;
988                 usblp->rcomplete = 1;
989                 spin_unlock_irqrestore(&usblp->lock, flags);
990                 goto raise_submit;
991         }
992
993         return 0;
994
995 raise_submit:
996         usb_unanchor_urb(urb);
997         usb_free_urb(urb);
998 raise_urb:
999         return rc;
1000 }
1001
1002 /*
1003  * Checks for printers that have quirks, such as requiring unidirectional
1004  * communication but reporting bidirectional; currently some HP printers
1005  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1006  * sent at each open (like some Epsons).
1007  * Returns 1 if found, 0 if not found.
1008  *
1009  * HP recommended that we use the bidirectional interface but
1010  * don't attempt any bulk IN transfers from the IN endpoint.
1011  * Here's some more detail on the problem:
1012  * The problem is not that it isn't bidirectional though. The problem
1013  * is that if you request a device ID, or status information, while
1014  * the buffers are full, the return data will end up in the print data
1015  * buffer. For example if you make sure you never request the device ID
1016  * while you are sending print data, and you don't try to query the
1017  * printer status every couple of milliseconds, you will probably be OK.
1018  */
1019 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
1020 {
1021         int i;
1022
1023         for (i = 0; quirk_printers[i].vendorId; i++) {
1024                 if (vendor == quirk_printers[i].vendorId &&
1025                     product == quirk_printers[i].productId)
1026                         return quirk_printers[i].quirks;
1027         }
1028         return 0;
1029 }
1030
1031 static const struct file_operations usblp_fops = {
1032         .owner =        THIS_MODULE,
1033         .read =         usblp_read,
1034         .write =        usblp_write,
1035         .poll =         usblp_poll,
1036         .unlocked_ioctl =       usblp_ioctl,
1037         .compat_ioctl =         usblp_ioctl,
1038         .open =         usblp_open,
1039         .release =      usblp_release,
1040 };
1041
1042 static struct usb_class_driver usblp_class = {
1043         .name =         "lp%d",
1044         .fops =         &usblp_fops,
1045         .minor_base =   USBLP_MINOR_BASE,
1046 };
1047
1048 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1049 {
1050         struct usb_interface *intf = to_usb_interface(dev);
1051         struct usblp *usblp = usb_get_intfdata (intf);
1052
1053         if (usblp->device_id_string[0] == 0 &&
1054             usblp->device_id_string[1] == 0)
1055                 return 0;
1056
1057         return sprintf(buf, "%s", usblp->device_id_string+2);
1058 }
1059
1060 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1061
1062 static int usblp_probe(struct usb_interface *intf,
1063                        const struct usb_device_id *id)
1064 {
1065         struct usb_device *dev = interface_to_usbdev (intf);
1066         struct usblp *usblp = NULL;
1067         int protocol;
1068         int retval;
1069
1070         /* Malloc and start initializing usblp structure so we can use it
1071          * directly. */
1072         if (!(usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL))) {
1073                 retval = -ENOMEM;
1074                 goto abort;
1075         }
1076         usblp->dev = dev;
1077         mutex_init(&usblp->wmut);
1078         mutex_init (&usblp->mut);
1079         spin_lock_init(&usblp->lock);
1080         init_waitqueue_head(&usblp->rwait);
1081         init_waitqueue_head(&usblp->wwait);
1082         init_usb_anchor(&usblp->urbs);
1083         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1084         usblp->intf = intf;
1085
1086         /* Malloc device ID string buffer to the largest expected length,
1087          * since we can re-query it on an ioctl and a dynamic string
1088          * could change in length. */
1089         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1090                 retval = -ENOMEM;
1091                 goto abort;
1092         }
1093
1094         /*
1095          * Allocate read buffer. We somewhat wastefully
1096          * malloc both regardless of bidirectionality, because the
1097          * alternate setting can be changed later via an ioctl.
1098          */
1099         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1100                 retval = -ENOMEM;
1101                 goto abort;
1102         }
1103
1104         /* Allocate buffer for printer status */
1105         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1106         if (!usblp->statusbuf) {
1107                 retval = -ENOMEM;
1108                 goto abort;
1109         }
1110
1111         /* Lookup quirks for this printer. */
1112         usblp->quirks = usblp_quirks(
1113                 le16_to_cpu(dev->descriptor.idVendor),
1114                 le16_to_cpu(dev->descriptor.idProduct));
1115
1116         /* Analyze and pick initial alternate settings and endpoints. */
1117         protocol = usblp_select_alts(usblp);
1118         if (protocol < 0) {
1119                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
1120                         le16_to_cpu(dev->descriptor.idVendor),
1121                         le16_to_cpu(dev->descriptor.idProduct));
1122                 retval = -ENODEV;
1123                 goto abort;
1124         }
1125
1126         /* Setup the selected alternate setting and endpoints. */
1127         if (usblp_set_protocol(usblp, protocol) < 0) {
1128                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1129                 goto abort;
1130         }
1131
1132         /* Retrieve and store the device ID string. */
1133         usblp_cache_device_id_string(usblp);
1134         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1135         if (retval)
1136                 goto abort_intfdata;
1137
1138 #ifdef DEBUG
1139         usblp_check_status(usblp, 0);
1140 #endif
1141
1142         usb_set_intfdata (intf, usblp);
1143
1144         usblp->present = 1;
1145
1146         retval = usb_register_dev(intf, &usblp_class);
1147         if (retval) {
1148                 printk(KERN_ERR "usblp: Not able to get a minor"
1149                     " (base %u, slice default): %d\n",
1150                     USBLP_MINOR_BASE, retval);
1151                 goto abort_intfdata;
1152         }
1153         usblp->minor = intf->minor;
1154         printk(KERN_INFO "usblp%d: USB %sdirectional printer dev %d "
1155                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1156                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1157                 usblp->ifnum,
1158                 usblp->protocol[usblp->current_protocol].alt_setting,
1159                 usblp->current_protocol,
1160                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1161                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1162
1163         return 0;
1164
1165 abort_intfdata:
1166         usb_set_intfdata (intf, NULL);
1167         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1168 abort:
1169         if (usblp) {
1170                 kfree(usblp->readbuf);
1171                 kfree(usblp->statusbuf);
1172                 kfree(usblp->device_id_string);
1173                 kfree(usblp);
1174         }
1175         return retval;
1176 }
1177
1178 /*
1179  * We are a "new" style driver with usb_device_id table,
1180  * but our requirements are too intricate for simple match to handle.
1181  *
1182  * The "proto_bias" option may be used to specify the preferred protocol
1183  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1184  * supports the preferred protocol, then we bind to it.
1185  *
1186  * The best interface for us is 7/1/2, because it is compatible
1187  * with a stream of characters. If we find it, we bind to it.
1188  *
1189  * Note that the people from hpoj.sourceforge.net need to be able to
1190  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1191  *
1192  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1193  * stream-compatible, because this matches the behaviour of the old code.
1194  *
1195  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1196  */
1197 static int usblp_select_alts(struct usblp *usblp)
1198 {
1199         struct usb_interface *if_alt;
1200         struct usb_host_interface *ifd;
1201         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1202         int p, i, e;
1203
1204         if_alt = usblp->intf;
1205
1206         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1207                 usblp->protocol[p].alt_setting = -1;
1208
1209         /* Find out what we have. */
1210         for (i = 0; i < if_alt->num_altsetting; i++) {
1211                 ifd = &if_alt->altsetting[i];
1212
1213                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1214                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1215                                 continue;
1216
1217                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1218                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1219                         continue;
1220
1221                 /* Look for bulk OUT and IN endpoints. */
1222                 epwrite = epread = NULL;
1223                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1224                         epd = &ifd->endpoint[e].desc;
1225
1226                         if (usb_endpoint_is_bulk_out(epd))
1227                                 if (!epwrite)
1228                                         epwrite = epd;
1229
1230                         if (usb_endpoint_is_bulk_in(epd))
1231                                 if (!epread)
1232                                         epread = epd;
1233                 }
1234
1235                 /* Ignore buggy hardware without the right endpoints. */
1236                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1237                         continue;
1238
1239                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1240                  * and buggy bidirectional printers. */
1241                 if (ifd->desc.bInterfaceProtocol == 1) {
1242                         epread = NULL;
1243                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1244                         printk(KERN_INFO "usblp%d: Disabling reads from "
1245                             "problematic bidirectional printer\n",
1246                             usblp->minor);
1247                         epread = NULL;
1248                 }
1249
1250                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1251                                 ifd->desc.bAlternateSetting;
1252                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1253                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1254         }
1255
1256         /* If our requested protocol is supported, then use it. */
1257         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1258             proto_bias <= USBLP_LAST_PROTOCOL &&
1259             usblp->protocol[proto_bias].alt_setting != -1)
1260                 return proto_bias;
1261
1262         /* Ordering is important here. */
1263         if (usblp->protocol[2].alt_setting != -1)
1264                 return 2;
1265         if (usblp->protocol[1].alt_setting != -1)
1266                 return 1;
1267         if (usblp->protocol[3].alt_setting != -1)
1268                 return 3;
1269
1270         /* If nothing is available, then don't bind to this device. */
1271         return -1;
1272 }
1273
1274 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1275 {
1276         int r, alts;
1277
1278         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1279                 return -EINVAL;
1280
1281         alts = usblp->protocol[protocol].alt_setting;
1282         if (alts < 0)
1283                 return -EINVAL;
1284         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1285         if (r < 0) {
1286                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1287                         alts, usblp->ifnum);
1288                 return r;
1289         }
1290
1291         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1292         usblp->current_protocol = protocol;
1293         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1294         return 0;
1295 }
1296
1297 /* Retrieves and caches device ID string.
1298  * Returns length, including length bytes but not null terminator.
1299  * On error, returns a negative errno value. */
1300 static int usblp_cache_device_id_string(struct usblp *usblp)
1301 {
1302         int err, length;
1303
1304         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1305         if (err < 0) {
1306                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1307                         usblp->minor, err);
1308                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1309                 return -EIO;
1310         }
1311
1312         /* First two bytes are length in big-endian.
1313          * They count themselves, and we copy them into
1314          * the user's buffer. */
1315         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1316         if (length < 2)
1317                 length = 2;
1318         else if (length >= USBLP_DEVICE_ID_SIZE)
1319                 length = USBLP_DEVICE_ID_SIZE - 1;
1320         usblp->device_id_string[length] = '\0';
1321
1322         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1323                 usblp->minor, length, &usblp->device_id_string[2]);
1324
1325         return length;
1326 }
1327
1328 static void usblp_disconnect(struct usb_interface *intf)
1329 {
1330         struct usblp *usblp = usb_get_intfdata (intf);
1331
1332         usb_deregister_dev(intf, &usblp_class);
1333
1334         if (!usblp || !usblp->dev) {
1335                 err("bogus disconnect");
1336                 BUG ();
1337         }
1338
1339         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1340
1341         mutex_lock (&usblp_mutex);
1342         mutex_lock (&usblp->mut);
1343         usblp->present = 0;
1344         wake_up(&usblp->wwait);
1345         wake_up(&usblp->rwait);
1346         usb_set_intfdata (intf, NULL);
1347
1348         usblp_unlink_urbs(usblp);
1349         mutex_unlock (&usblp->mut);
1350
1351         if (!usblp->used)
1352                 usblp_cleanup (usblp);
1353         mutex_unlock (&usblp_mutex);
1354 }
1355
1356 static int usblp_suspend (struct usb_interface *intf, pm_message_t message)
1357 {
1358         struct usblp *usblp = usb_get_intfdata (intf);
1359
1360         /* we take no more IO */
1361         usblp->sleeping = 1;
1362         usblp_unlink_urbs(usblp);
1363 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1364         /* not strictly necessary, but just in case */
1365         wake_up(&usblp->wwait);
1366         wake_up(&usblp->rwait);
1367 #endif
1368
1369         return 0;
1370 }
1371
1372 static int usblp_resume (struct usb_interface *intf)
1373 {
1374         struct usblp *usblp = usb_get_intfdata (intf);
1375         int r;
1376
1377         usblp->sleeping = 0;
1378         r = handle_bidir (usblp);
1379
1380         return r;
1381 }
1382
1383 static struct usb_device_id usblp_ids [] = {
1384         { USB_DEVICE_INFO(7, 1, 1) },
1385         { USB_DEVICE_INFO(7, 1, 2) },
1386         { USB_DEVICE_INFO(7, 1, 3) },
1387         { USB_INTERFACE_INFO(7, 1, 1) },
1388         { USB_INTERFACE_INFO(7, 1, 2) },
1389         { USB_INTERFACE_INFO(7, 1, 3) },
1390         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1391         { }                                             /* Terminating entry */
1392 };
1393
1394 MODULE_DEVICE_TABLE (usb, usblp_ids);
1395
1396 static struct usb_driver usblp_driver = {
1397         .name =         "usblp",
1398         .probe =        usblp_probe,
1399         .disconnect =   usblp_disconnect,
1400         .suspend =      usblp_suspend,
1401         .resume =       usblp_resume,
1402         .id_table =     usblp_ids,
1403         .supports_autosuspend = 1,
1404 };
1405
1406 static int __init usblp_init(void)
1407 {
1408         return usb_register(&usblp_driver);
1409 }
1410
1411 static void __exit usblp_exit(void)
1412 {
1413         usb_deregister(&usblp_driver);
1414 }
1415
1416 module_init(usblp_init);
1417 module_exit(usblp_exit);
1418
1419 MODULE_AUTHOR( DRIVER_AUTHOR );
1420 MODULE_DESCRIPTION( DRIVER_DESC );
1421 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1422 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1423 MODULE_LICENSE("GPL");