Merge commit 'v3.4.4' into android-tegra-nv-3.4
[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@ucw.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_alloc_coherent() 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 #include <linux/ratelimit.h>
62
63 /*
64  * Version Information
65  */
66 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
67 #define DRIVER_DESC "USB Printer Device Class driver"
68
69 #define USBLP_BUF_SIZE          8192
70 #define USBLP_BUF_SIZE_IN       1024
71 #define USBLP_DEVICE_ID_SIZE    1024
72
73 /* ioctls: */
74 #define IOCNR_GET_DEVICE_ID             1
75 #define IOCNR_GET_PROTOCOLS             2
76 #define IOCNR_SET_PROTOCOL              3
77 #define IOCNR_HP_SET_CHANNEL            4
78 #define IOCNR_GET_BUS_ADDRESS           5
79 #define IOCNR_GET_VID_PID               6
80 #define IOCNR_SOFT_RESET                7
81 /* Get device_id string: */
82 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
83 /* The following ioctls were added for http://hpoj.sourceforge.net: */
84 /* Get two-int array:
85  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
86  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
87 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
88 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
89 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
90 /* Set channel number (HP Vendor-specific command): */
91 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
92 /* Get two-int array: [0]=bus number, [1]=device address: */
93 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
94 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
95 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
96 /* Perform class specific soft reset */
97 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
98
99 /*
100  * A DEVICE_ID string may include the printer's serial number.
101  * It should end with a semi-colon (';').
102  * An example from an HP 970C DeskJet printer is (this is one long string,
103  * with the serial number changed):
104 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
105  */
106
107 /*
108  * USB Printer Requests
109  */
110
111 #define USBLP_REQ_GET_ID                        0x00
112 #define USBLP_REQ_GET_STATUS                    0x01
113 #define USBLP_REQ_RESET                         0x02
114 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
115
116 #define USBLP_MINORS            16
117 #define USBLP_MINOR_BASE        0
118
119 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
120
121 #define USBLP_FIRST_PROTOCOL    1
122 #define USBLP_LAST_PROTOCOL     3
123 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
124
125 /*
126  * some arbitrary status buffer size;
127  * need a status buffer that is allocated via kmalloc(), not on stack
128  */
129 #define STATUS_BUF_SIZE         8
130
131 /*
132  * Locks down the locking order:
133  * ->wmut locks wstatus.
134  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
135  * [rw]status. We only touch status when we know the side idle.
136  * ->lock locks what interrupt accesses.
137  */
138 struct usblp {
139         struct usb_device       *dev;                   /* USB device */
140         struct mutex            wmut;
141         struct mutex            mut;
142         spinlock_t              lock;           /* locks rcomplete, wcomplete */
143         char                    *readbuf;               /* read transfer_buffer */
144         char                    *statusbuf;             /* status transfer_buffer */
145         struct usb_anchor       urbs;
146         wait_queue_head_t       rwait, wwait;
147         int                     readcount;              /* Counter for reads */
148         int                     ifnum;                  /* Interface number */
149         struct usb_interface    *intf;                  /* The interface */
150         /* Alternate-setting numbers and endpoints for each protocol
151          * (7/1/{index=1,2,3}) that the device supports: */
152         struct {
153                 int                             alt_setting;
154                 struct usb_endpoint_descriptor  *epwrite;
155                 struct usb_endpoint_descriptor  *epread;
156         }                       protocol[USBLP_MAX_PROTOCOLS];
157         int                     current_protocol;
158         int                     minor;                  /* minor number of device */
159         int                     wcomplete, rcomplete;
160         int                     wstatus;        /* bytes written or error */
161         int                     rstatus;        /* bytes ready or error */
162         unsigned int            quirks;                 /* quirks flags */
163         unsigned int            flags;                  /* mode flags */
164         unsigned char           used;                   /* True if open */
165         unsigned char           present;                /* True if not disconnected */
166         unsigned char           bidir;                  /* interface is bidirectional */
167         unsigned char           no_paper;               /* Paper Out happened */
168         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
169                                                         /* first 2 bytes are (big-endian) length */
170 };
171
172 #ifdef DEBUG
173 static void usblp_dump(struct usblp *usblp)
174 {
175         int p;
176
177         dbg("usblp=0x%p", usblp);
178         dbg("dev=0x%p", usblp->dev);
179         dbg("present=%d", usblp->present);
180         dbg("readbuf=0x%p", usblp->readbuf);
181         dbg("readcount=%d", usblp->readcount);
182         dbg("ifnum=%d", usblp->ifnum);
183     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
184         dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
185         dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
186         dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
187     }
188         dbg("current_protocol=%d", usblp->current_protocol);
189         dbg("minor=%d", usblp->minor);
190         dbg("wstatus=%d", usblp->wstatus);
191         dbg("rstatus=%d", usblp->rstatus);
192         dbg("quirks=%d", usblp->quirks);
193         dbg("used=%d", usblp->used);
194         dbg("bidir=%d", usblp->bidir);
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         retval = usb_control_msg(usblp->dev,
263                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
264                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
265         dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
266                 request, !!dir, recip, value, index, len, retval);
267         return retval < 0 ? retval : 0;
268 }
269
270 #define usblp_read_status(usblp, status)\
271         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
272 #define usblp_get_id(usblp, config, id, maxlen)\
273         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
274 #define usblp_reset(usblp)\
275         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
276
277 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
278         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
279
280 /*
281  * See the description for usblp_select_alts() below for the usage
282  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
283  * case of any trouble.
284  */
285 static int proto_bias = -1;
286
287 /*
288  * URB callback.
289  */
290
291 static void usblp_bulk_read(struct urb *urb)
292 {
293         struct usblp *usblp = urb->context;
294         int status = urb->status;
295
296         if (usblp->present && usblp->used) {
297                 if (status)
298                         printk(KERN_WARNING "usblp%d: "
299                             "nonzero read bulk status received: %d\n",
300                             usblp->minor, status);
301         }
302         spin_lock(&usblp->lock);
303         if (status < 0)
304                 usblp->rstatus = status;
305         else
306                 usblp->rstatus = urb->actual_length;
307         usblp->rcomplete = 1;
308         wake_up(&usblp->rwait);
309         spin_unlock(&usblp->lock);
310
311         usb_free_urb(urb);
312 }
313
314 static void usblp_bulk_write(struct urb *urb)
315 {
316         struct usblp *usblp = urb->context;
317         int status = urb->status;
318
319         if (usblp->present && usblp->used) {
320                 if (status)
321                         printk(KERN_WARNING "usblp%d: "
322                             "nonzero write bulk status received: %d\n",
323                             usblp->minor, status);
324         }
325         spin_lock(&usblp->lock);
326         if (status < 0)
327                 usblp->wstatus = status;
328         else
329                 usblp->wstatus = urb->actual_length;
330         usblp->no_paper = 0;
331         usblp->wcomplete = 1;
332         wake_up(&usblp->wwait);
333         spin_unlock(&usblp->lock);
334
335         usb_free_urb(urb);
336 }
337
338 /*
339  * Get and print printer errors.
340  */
341
342 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
343
344 static int usblp_check_status(struct usblp *usblp, int err)
345 {
346         unsigned char status, newerr = 0;
347         int error;
348
349         mutex_lock(&usblp->mut);
350         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
351                 mutex_unlock(&usblp->mut);
352                 printk_ratelimited(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) {
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         usblp = usb_get_intfdata(intf);
405         if (!usblp || !usblp->dev || !usblp->present)
406                 goto out;
407
408         retval = -EBUSY;
409         if (usblp->used)
410                 goto out;
411
412         /*
413          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
414          *  - We do not want persistent state which close(2) does not clear
415          *  - It is not used anyway, according to CUPS people
416          */
417
418         retval = usb_autopm_get_interface(intf);
419         if (retval < 0)
420                 goto out;
421         usblp->used = 1;
422         file->private_data = usblp;
423
424         usblp->wcomplete = 1; /* we begin writeable */
425         usblp->wstatus = 0;
426         usblp->rcomplete = 0;
427
428         if (handle_bidir(usblp) < 0) {
429                 usb_autopm_put_interface(intf);
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) ? POLLIN  | POLLRDNORM : 0) |
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         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
504                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
505
506         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
507
508                 switch (_IOC_NR(cmd)) {
509
510                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
511                         if (_IOC_DIR(cmd) != _IOC_READ) {
512                                 retval = -EINVAL;
513                                 goto done;
514                         }
515
516                         length = usblp_cache_device_id_string(usblp);
517                         if (length < 0) {
518                                 retval = length;
519                                 goto done;
520                         }
521                         if (length > _IOC_SIZE(cmd))
522                                 length = _IOC_SIZE(cmd); /* truncate */
523
524                         if (copy_to_user((void __user *) arg,
525                                         usblp->device_id_string,
526                                         (unsigned long) length)) {
527                                 retval = -EFAULT;
528                                 goto done;
529                         }
530
531                         break;
532
533                 case IOCNR_GET_PROTOCOLS:
534                         if (_IOC_DIR(cmd) != _IOC_READ ||
535                             _IOC_SIZE(cmd) < sizeof(twoints)) {
536                                 retval = -EINVAL;
537                                 goto done;
538                         }
539
540                         twoints[0] = usblp->current_protocol;
541                         twoints[1] = 0;
542                         for (i = USBLP_FIRST_PROTOCOL;
543                              i <= USBLP_LAST_PROTOCOL; i++) {
544                                 if (usblp->protocol[i].alt_setting >= 0)
545                                         twoints[1] |= (1<<i);
546                         }
547
548                         if (copy_to_user((void __user *)arg,
549                                         (unsigned char *)twoints,
550                                         sizeof(twoints))) {
551                                 retval = -EFAULT;
552                                 goto done;
553                         }
554
555                         break;
556
557                 case IOCNR_SET_PROTOCOL:
558                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
559                                 retval = -EINVAL;
560                                 goto done;
561                         }
562
563 #ifdef DEBUG
564                         if (arg == -10) {
565                                 usblp_dump(usblp);
566                                 break;
567                         }
568 #endif
569
570                         usblp_unlink_urbs(usblp);
571                         retval = usblp_set_protocol(usblp, arg);
572                         if (retval < 0) {
573                                 usblp_set_protocol(usblp,
574                                         usblp->current_protocol);
575                         }
576                         break;
577
578                 case IOCNR_HP_SET_CHANNEL:
579                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
580                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
581                             usblp->quirks & USBLP_QUIRK_BIDIR) {
582                                 retval = -EINVAL;
583                                 goto done;
584                         }
585
586                         err = usblp_hp_channel_change_request(usblp,
587                                 arg, &newChannel);
588                         if (err < 0) {
589                                 dev_err(&usblp->dev->dev,
590                                         "usblp%d: error = %d setting "
591                                         "HP channel\n",
592                                         usblp->minor, err);
593                                 retval = -EIO;
594                                 goto done;
595                         }
596
597                         dbg("usblp%d requested/got HP channel %ld/%d",
598                                 usblp->minor, arg, newChannel);
599                         break;
600
601                 case IOCNR_GET_BUS_ADDRESS:
602                         if (_IOC_DIR(cmd) != _IOC_READ ||
603                             _IOC_SIZE(cmd) < sizeof(twoints)) {
604                                 retval = -EINVAL;
605                                 goto done;
606                         }
607
608                         twoints[0] = usblp->dev->bus->busnum;
609                         twoints[1] = usblp->dev->devnum;
610                         if (copy_to_user((void __user *)arg,
611                                         (unsigned char *)twoints,
612                                         sizeof(twoints))) {
613                                 retval = -EFAULT;
614                                 goto done;
615                         }
616
617                         dbg("usblp%d is bus=%d, device=%d",
618                                 usblp->minor, twoints[0], twoints[1]);
619                         break;
620
621                 case IOCNR_GET_VID_PID:
622                         if (_IOC_DIR(cmd) != _IOC_READ ||
623                             _IOC_SIZE(cmd) < sizeof(twoints)) {
624                                 retval = -EINVAL;
625                                 goto done;
626                         }
627
628                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
629                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
630                         if (copy_to_user((void __user *)arg,
631                                         (unsigned char *)twoints,
632                                         sizeof(twoints))) {
633                                 retval = -EFAULT;
634                                 goto done;
635                         }
636
637                         dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
638                                 usblp->minor, twoints[0], twoints[1]);
639                         break;
640
641                 case IOCNR_SOFT_RESET:
642                         if (_IOC_DIR(cmd) != _IOC_NONE) {
643                                 retval = -EINVAL;
644                                 goto done;
645                         }
646                         retval = usblp_reset(usblp);
647                         break;
648                 default:
649                         retval = -ENOTTY;
650                 }
651         else    /* old-style ioctl value */
652                 switch (cmd) {
653
654                 case LPGETSTATUS:
655                         if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
656                                 printk_ratelimited(KERN_ERR "usblp%d:"
657                                             "failed reading printer status (%d)\n",
658                                             usblp->minor, retval);
659                                 retval = -EIO;
660                                 goto done;
661                         }
662                         status = *usblp->statusbuf;
663                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
664                                 retval = -EFAULT;
665                         break;
666
667                 case LPABORT:
668                         if (arg)
669                                 usblp->flags |= LP_ABORT;
670                         else
671                                 usblp->flags &= ~LP_ABORT;
672                         break;
673
674                 default:
675                         retval = -ENOTTY;
676                 }
677
678 done:
679         mutex_unlock(&usblp->mut);
680         return retval;
681 }
682
683 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
684 {
685         struct urb *urb;
686         char *writebuf;
687
688         if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
689                 return NULL;
690         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
691                 kfree(writebuf);
692                 return NULL;
693         }
694
695         usb_fill_bulk_urb(urb, usblp->dev,
696                 usb_sndbulkpipe(usblp->dev,
697                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
698                 writebuf, transfer_length, usblp_bulk_write, usblp);
699         urb->transfer_flags |= URB_FREE_BUFFER;
700
701         return urb;
702 }
703
704 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
705 {
706         struct usblp *usblp = file->private_data;
707         struct urb *writeurb;
708         int rv;
709         int transfer_length;
710         ssize_t writecount = 0;
711
712         if (mutex_lock_interruptible(&usblp->wmut)) {
713                 rv = -EINTR;
714                 goto raise_biglock;
715         }
716         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
717                 goto raise_wait;
718
719         while (writecount < count) {
720                 /*
721                  * Step 1: Submit next block.
722                  */
723                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
724                         transfer_length = USBLP_BUF_SIZE;
725
726                 rv = -ENOMEM;
727                 if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
728                         goto raise_urb;
729                 usb_anchor_urb(writeurb, &usblp->urbs);
730
731                 if (copy_from_user(writeurb->transfer_buffer,
732                                    buffer + writecount, transfer_length)) {
733                         rv = -EFAULT;
734                         goto raise_badaddr;
735                 }
736
737                 spin_lock_irq(&usblp->lock);
738                 usblp->wcomplete = 0;
739                 spin_unlock_irq(&usblp->lock);
740                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
741                         usblp->wstatus = 0;
742                         spin_lock_irq(&usblp->lock);
743                         usblp->no_paper = 0;
744                         usblp->wcomplete = 1;
745                         wake_up(&usblp->wwait);
746                         spin_unlock_irq(&usblp->lock);
747                         if (rv != -ENOMEM)
748                                 rv = -EIO;
749                         goto raise_submit;
750                 }
751
752                 /*
753                  * Step 2: Wait for transfer to end, collect results.
754                  */
755                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
756                 if (rv < 0) {
757                         if (rv == -EAGAIN) {
758                                 /* Presume that it's going to complete well. */
759                                 writecount += transfer_length;
760                         }
761                         if (rv == -ENOSPC) {
762                                 spin_lock_irq(&usblp->lock);
763                                 usblp->no_paper = 1;    /* Mark for poll(2) */
764                                 spin_unlock_irq(&usblp->lock);
765                                 writecount += transfer_length;
766                         }
767                         /* Leave URB dangling, to be cleaned on close. */
768                         goto collect_error;
769                 }
770
771                 if (usblp->wstatus < 0) {
772                         rv = -EIO;
773                         goto collect_error;
774                 }
775                 /*
776                  * This is critical: it must be our URB, not other writer's.
777                  * The wmut exists mainly to cover us here.
778                  */
779                 writecount += usblp->wstatus;
780         }
781
782         mutex_unlock(&usblp->wmut);
783         return writecount;
784
785 raise_submit:
786 raise_badaddr:
787         usb_unanchor_urb(writeurb);
788         usb_free_urb(writeurb);
789 raise_urb:
790 raise_wait:
791 collect_error:          /* Out of raise sequence */
792         mutex_unlock(&usblp->wmut);
793 raise_biglock:
794         return writecount ? writecount : rv;
795 }
796
797 /*
798  * Notice that we fail to restart in a few cases: on EFAULT, on restart
799  * error, etc. This is the historical behaviour. In all such cases we return
800  * EIO, and applications loop in order to get the new read going.
801  */
802 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
803 {
804         struct usblp *usblp = file->private_data;
805         ssize_t count;
806         ssize_t avail;
807         int rv;
808
809         if (!usblp->bidir)
810                 return -EINVAL;
811
812         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
813         if (rv < 0)
814                 return rv;
815
816         if ((avail = usblp->rstatus) < 0) {
817                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
818                     usblp->minor, (int)avail);
819                 usblp_submit_read(usblp);
820                 count = -EIO;
821                 goto done;
822         }
823
824         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
825         if (count != 0 &&
826             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
827                 count = -EFAULT;
828                 goto done;
829         }
830
831         if ((usblp->readcount += count) == avail) {
832                 if (usblp_submit_read(usblp) < 0) {
833                         /* We don't want to leak USB return codes into errno. */
834                         if (count == 0)
835                                 count = -EIO;
836                         goto done;
837                 }
838         }
839
840 done:
841         mutex_unlock(&usblp->mut);
842         return count;
843 }
844
845 /*
846  * Wait for the write path to come idle.
847  * This is called under the ->wmut, so the idle path stays idle.
848  *
849  * Our write path has a peculiar property: it does not buffer like a tty,
850  * but waits for the write to succeed. This allows our ->release to bug out
851  * without waiting for writes to drain. But it obviously does not work
852  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
853  * select(2) or poll(2) to wait for the buffer to drain before closing.
854  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
855  */
856 static int usblp_wwait(struct usblp *usblp, int nonblock)
857 {
858         DECLARE_WAITQUEUE(waita, current);
859         int rc;
860         int err = 0;
861
862         add_wait_queue(&usblp->wwait, &waita);
863         for (;;) {
864                 set_current_state(TASK_INTERRUPTIBLE);
865                 if (mutex_lock_interruptible(&usblp->mut)) {
866                         rc = -EINTR;
867                         break;
868                 }
869                 rc = usblp_wtest(usblp, nonblock);
870                 mutex_unlock(&usblp->mut);
871                 if (rc <= 0)
872                         break;
873
874                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
875                         if (usblp->flags & LP_ABORT) {
876                                 err = usblp_check_status(usblp, err);
877                                 if (err == 1) { /* Paper out */
878                                         rc = -ENOSPC;
879                                         break;
880                                 }
881                         } else {
882                                 /* Prod the printer, Gentoo#251237. */
883                                 mutex_lock(&usblp->mut);
884                                 usblp_read_status(usblp, usblp->statusbuf);
885                                 mutex_unlock(&usblp->mut);
886                         }
887                 }
888         }
889         set_current_state(TASK_RUNNING);
890         remove_wait_queue(&usblp->wwait, &waita);
891         return rc;
892 }
893
894 static int usblp_wtest(struct usblp *usblp, int nonblock)
895 {
896         unsigned long flags;
897
898         if (!usblp->present)
899                 return -ENODEV;
900         if (signal_pending(current))
901                 return -EINTR;
902         spin_lock_irqsave(&usblp->lock, flags);
903         if (usblp->wcomplete) {
904                 spin_unlock_irqrestore(&usblp->lock, flags);
905                 return 0;
906         }
907         spin_unlock_irqrestore(&usblp->lock, flags);
908         if (nonblock)
909                 return -EAGAIN;
910         return 1;
911 }
912
913 /*
914  * Wait for read bytes to become available. This probably should have been
915  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
916  * name for functions which lock and return.
917  *
918  * We do not use wait_event_interruptible because it makes locking iffy.
919  */
920 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
921 {
922         DECLARE_WAITQUEUE(waita, current);
923         int rc;
924
925         add_wait_queue(&usblp->rwait, &waita);
926         for (;;) {
927                 if (mutex_lock_interruptible(&usblp->mut)) {
928                         rc = -EINTR;
929                         break;
930                 }
931                 set_current_state(TASK_INTERRUPTIBLE);
932                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
933                         mutex_unlock(&usblp->mut);
934                         break;
935                 }
936                 if (rc == 0)    /* Keep it locked */
937                         break;
938                 mutex_unlock(&usblp->mut);
939                 schedule();
940         }
941         set_current_state(TASK_RUNNING);
942         remove_wait_queue(&usblp->rwait, &waita);
943         return rc;
944 }
945
946 static int usblp_rtest(struct usblp *usblp, int nonblock)
947 {
948         unsigned long flags;
949
950         if (!usblp->present)
951                 return -ENODEV;
952         if (signal_pending(current))
953                 return -EINTR;
954         spin_lock_irqsave(&usblp->lock, flags);
955         if (usblp->rcomplete) {
956                 spin_unlock_irqrestore(&usblp->lock, flags);
957                 return 0;
958         }
959         spin_unlock_irqrestore(&usblp->lock, flags);
960         if (nonblock)
961                 return -EAGAIN;
962         return 1;
963 }
964
965 /*
966  * Please check ->bidir and other such things outside for now.
967  */
968 static int usblp_submit_read(struct usblp *usblp)
969 {
970         struct urb *urb;
971         unsigned long flags;
972         int rc;
973
974         rc = -ENOMEM;
975         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
976                 goto raise_urb;
977
978         usb_fill_bulk_urb(urb, usblp->dev,
979                 usb_rcvbulkpipe(usblp->dev,
980                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
981                 usblp->readbuf, USBLP_BUF_SIZE_IN,
982                 usblp_bulk_read, usblp);
983         usb_anchor_urb(urb, &usblp->urbs);
984
985         spin_lock_irqsave(&usblp->lock, flags);
986         usblp->readcount = 0; /* XXX Why here? */
987         usblp->rcomplete = 0;
988         spin_unlock_irqrestore(&usblp->lock, flags);
989         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
990                 dbg("error submitting urb (%d)", rc);
991                 spin_lock_irqsave(&usblp->lock, flags);
992                 usblp->rstatus = rc;
993                 usblp->rcomplete = 1;
994                 spin_unlock_irqrestore(&usblp->lock, flags);
995                 goto raise_submit;
996         }
997
998         return 0;
999
1000 raise_submit:
1001         usb_unanchor_urb(urb);
1002         usb_free_urb(urb);
1003 raise_urb:
1004         return rc;
1005 }
1006
1007 /*
1008  * Checks for printers that have quirks, such as requiring unidirectional
1009  * communication but reporting bidirectional; currently some HP printers
1010  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1011  * sent at each open (like some Epsons).
1012  * Returns 1 if found, 0 if not found.
1013  *
1014  * HP recommended that we use the bidirectional interface but
1015  * don't attempt any bulk IN transfers from the IN endpoint.
1016  * Here's some more detail on the problem:
1017  * The problem is not that it isn't bidirectional though. The problem
1018  * is that if you request a device ID, or status information, while
1019  * the buffers are full, the return data will end up in the print data
1020  * buffer. For example if you make sure you never request the device ID
1021  * while you are sending print data, and you don't try to query the
1022  * printer status every couple of milliseconds, you will probably be OK.
1023  */
1024 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1025 {
1026         int i;
1027
1028         for (i = 0; quirk_printers[i].vendorId; i++) {
1029                 if (vendor == quirk_printers[i].vendorId &&
1030                     product == quirk_printers[i].productId)
1031                         return quirk_printers[i].quirks;
1032         }
1033         return 0;
1034 }
1035
1036 static const struct file_operations usblp_fops = {
1037         .owner =        THIS_MODULE,
1038         .read =         usblp_read,
1039         .write =        usblp_write,
1040         .poll =         usblp_poll,
1041         .unlocked_ioctl =       usblp_ioctl,
1042         .compat_ioctl =         usblp_ioctl,
1043         .open =         usblp_open,
1044         .release =      usblp_release,
1045         .llseek =       noop_llseek,
1046 };
1047
1048 static char *usblp_devnode(struct device *dev, umode_t *mode)
1049 {
1050         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1051 }
1052
1053 static struct usb_class_driver usblp_class = {
1054         .name =         "lp%d",
1055         .devnode =      usblp_devnode,
1056         .fops =         &usblp_fops,
1057         .minor_base =   USBLP_MINOR_BASE,
1058 };
1059
1060 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1061 {
1062         struct usb_interface *intf = to_usb_interface(dev);
1063         struct usblp *usblp = usb_get_intfdata(intf);
1064
1065         if (usblp->device_id_string[0] == 0 &&
1066             usblp->device_id_string[1] == 0)
1067                 return 0;
1068
1069         return sprintf(buf, "%s", usblp->device_id_string+2);
1070 }
1071
1072 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1073
1074 static int usblp_probe(struct usb_interface *intf,
1075                        const struct usb_device_id *id)
1076 {
1077         struct usb_device *dev = interface_to_usbdev(intf);
1078         struct usblp *usblp;
1079         int protocol;
1080         int retval;
1081
1082         /* Malloc and start initializing usblp structure so we can use it
1083          * directly. */
1084         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1085         if (!usblp) {
1086                 retval = -ENOMEM;
1087                 goto abort_ret;
1088         }
1089         usblp->dev = dev;
1090         mutex_init(&usblp->wmut);
1091         mutex_init(&usblp->mut);
1092         spin_lock_init(&usblp->lock);
1093         init_waitqueue_head(&usblp->rwait);
1094         init_waitqueue_head(&usblp->wwait);
1095         init_usb_anchor(&usblp->urbs);
1096         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1097         usblp->intf = intf;
1098
1099         /* Malloc device ID string buffer to the largest expected length,
1100          * since we can re-query it on an ioctl and a dynamic string
1101          * could change in length. */
1102         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1103                 retval = -ENOMEM;
1104                 goto abort;
1105         }
1106
1107         /*
1108          * Allocate read buffer. We somewhat wastefully
1109          * malloc both regardless of bidirectionality, because the
1110          * alternate setting can be changed later via an ioctl.
1111          */
1112         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1113                 retval = -ENOMEM;
1114                 goto abort;
1115         }
1116
1117         /* Allocate buffer for printer status */
1118         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1119         if (!usblp->statusbuf) {
1120                 retval = -ENOMEM;
1121                 goto abort;
1122         }
1123
1124         /* Lookup quirks for this printer. */
1125         usblp->quirks = usblp_quirks(
1126                 le16_to_cpu(dev->descriptor.idVendor),
1127                 le16_to_cpu(dev->descriptor.idProduct));
1128
1129         /* Analyze and pick initial alternate settings and endpoints. */
1130         protocol = usblp_select_alts(usblp);
1131         if (protocol < 0) {
1132                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
1133                         le16_to_cpu(dev->descriptor.idVendor),
1134                         le16_to_cpu(dev->descriptor.idProduct));
1135                 retval = -ENODEV;
1136                 goto abort;
1137         }
1138
1139         /* Setup the selected alternate setting and endpoints. */
1140         if (usblp_set_protocol(usblp, protocol) < 0) {
1141                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1142                 goto abort;
1143         }
1144
1145         /* Retrieve and store the device ID string. */
1146         usblp_cache_device_id_string(usblp);
1147         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1148         if (retval)
1149                 goto abort_intfdata;
1150
1151 #ifdef DEBUG
1152         usblp_check_status(usblp, 0);
1153 #endif
1154
1155         usb_set_intfdata(intf, usblp);
1156
1157         usblp->present = 1;
1158
1159         retval = usb_register_dev(intf, &usblp_class);
1160         if (retval) {
1161                 printk(KERN_ERR "usblp: Not able to get a minor"
1162                     " (base %u, slice default): %d\n",
1163                     USBLP_MINOR_BASE, retval);
1164                 goto abort_intfdata;
1165         }
1166         usblp->minor = intf->minor;
1167         printk(KERN_INFO "usblp%d: USB %sdirectional printer dev %d "
1168                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1169                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1170                 usblp->ifnum,
1171                 usblp->protocol[usblp->current_protocol].alt_setting,
1172                 usblp->current_protocol,
1173                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1174                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1175
1176         return 0;
1177
1178 abort_intfdata:
1179         usb_set_intfdata(intf, NULL);
1180         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1181 abort:
1182         kfree(usblp->readbuf);
1183         kfree(usblp->statusbuf);
1184         kfree(usblp->device_id_string);
1185         kfree(usblp);
1186 abort_ret:
1187         return retval;
1188 }
1189
1190 /*
1191  * We are a "new" style driver with usb_device_id table,
1192  * but our requirements are too intricate for simple match to handle.
1193  *
1194  * The "proto_bias" option may be used to specify the preferred protocol
1195  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1196  * supports the preferred protocol, then we bind to it.
1197  *
1198  * The best interface for us is 7/1/2, because it is compatible
1199  * with a stream of characters. If we find it, we bind to it.
1200  *
1201  * Note that the people from hpoj.sourceforge.net need to be able to
1202  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1203  *
1204  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1205  * stream-compatible, because this matches the behaviour of the old code.
1206  *
1207  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1208  */
1209 static int usblp_select_alts(struct usblp *usblp)
1210 {
1211         struct usb_interface *if_alt;
1212         struct usb_host_interface *ifd;
1213         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1214         int p, i, e;
1215
1216         if_alt = usblp->intf;
1217
1218         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1219                 usblp->protocol[p].alt_setting = -1;
1220
1221         /* Find out what we have. */
1222         for (i = 0; i < if_alt->num_altsetting; i++) {
1223                 ifd = &if_alt->altsetting[i];
1224
1225                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1226                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1227                                 continue;
1228
1229                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1230                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1231                         continue;
1232
1233                 /* Look for bulk OUT and IN endpoints. */
1234                 epwrite = epread = NULL;
1235                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1236                         epd = &ifd->endpoint[e].desc;
1237
1238                         if (usb_endpoint_is_bulk_out(epd))
1239                                 if (!epwrite)
1240                                         epwrite = epd;
1241
1242                         if (usb_endpoint_is_bulk_in(epd))
1243                                 if (!epread)
1244                                         epread = epd;
1245                 }
1246
1247                 /* Ignore buggy hardware without the right endpoints. */
1248                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1249                         continue;
1250
1251                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1252                  * and buggy bidirectional printers. */
1253                 if (ifd->desc.bInterfaceProtocol == 1) {
1254                         epread = NULL;
1255                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1256                         printk(KERN_INFO "usblp%d: Disabling reads from "
1257                             "problematic bidirectional printer\n",
1258                             usblp->minor);
1259                         epread = NULL;
1260                 }
1261
1262                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1263                                 ifd->desc.bAlternateSetting;
1264                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1265                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1266         }
1267
1268         /* If our requested protocol is supported, then use it. */
1269         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1270             proto_bias <= USBLP_LAST_PROTOCOL &&
1271             usblp->protocol[proto_bias].alt_setting != -1)
1272                 return proto_bias;
1273
1274         /* Ordering is important here. */
1275         if (usblp->protocol[2].alt_setting != -1)
1276                 return 2;
1277         if (usblp->protocol[1].alt_setting != -1)
1278                 return 1;
1279         if (usblp->protocol[3].alt_setting != -1)
1280                 return 3;
1281
1282         /* If nothing is available, then don't bind to this device. */
1283         return -1;
1284 }
1285
1286 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1287 {
1288         int r, alts;
1289
1290         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1291                 return -EINVAL;
1292
1293         alts = usblp->protocol[protocol].alt_setting;
1294         if (alts < 0)
1295                 return -EINVAL;
1296         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1297         if (r < 0) {
1298                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1299                         alts, usblp->ifnum);
1300                 return r;
1301         }
1302
1303         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1304         usblp->current_protocol = protocol;
1305         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1306         return 0;
1307 }
1308
1309 /* Retrieves and caches device ID string.
1310  * Returns length, including length bytes but not null terminator.
1311  * On error, returns a negative errno value. */
1312 static int usblp_cache_device_id_string(struct usblp *usblp)
1313 {
1314         int err, length;
1315
1316         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1317         if (err < 0) {
1318                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1319                         usblp->minor, err);
1320                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1321                 return -EIO;
1322         }
1323
1324         /* First two bytes are length in big-endian.
1325          * They count themselves, and we copy them into
1326          * the user's buffer. */
1327         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1328         if (length < 2)
1329                 length = 2;
1330         else if (length >= USBLP_DEVICE_ID_SIZE)
1331                 length = USBLP_DEVICE_ID_SIZE - 1;
1332         usblp->device_id_string[length] = '\0';
1333
1334         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1335                 usblp->minor, length, &usblp->device_id_string[2]);
1336
1337         return length;
1338 }
1339
1340 static void usblp_disconnect(struct usb_interface *intf)
1341 {
1342         struct usblp *usblp = usb_get_intfdata(intf);
1343
1344         usb_deregister_dev(intf, &usblp_class);
1345
1346         if (!usblp || !usblp->dev) {
1347                 dev_err(&intf->dev, "bogus disconnect\n");
1348                 BUG();
1349         }
1350
1351         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1352
1353         mutex_lock(&usblp_mutex);
1354         mutex_lock(&usblp->mut);
1355         usblp->present = 0;
1356         wake_up(&usblp->wwait);
1357         wake_up(&usblp->rwait);
1358         usb_set_intfdata(intf, NULL);
1359
1360         usblp_unlink_urbs(usblp);
1361         mutex_unlock(&usblp->mut);
1362
1363         if (!usblp->used)
1364                 usblp_cleanup(usblp);
1365         mutex_unlock(&usblp_mutex);
1366 }
1367
1368 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1369 {
1370         struct usblp *usblp = usb_get_intfdata(intf);
1371
1372         usblp_unlink_urbs(usblp);
1373 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1374         /* not strictly necessary, but just in case */
1375         wake_up(&usblp->wwait);
1376         wake_up(&usblp->rwait);
1377 #endif
1378
1379         return 0;
1380 }
1381
1382 static int usblp_resume(struct usb_interface *intf)
1383 {
1384         struct usblp *usblp = usb_get_intfdata(intf);
1385         int r;
1386
1387         r = handle_bidir(usblp);
1388
1389         return r;
1390 }
1391
1392 static const struct usb_device_id usblp_ids[] = {
1393         { USB_DEVICE_INFO(7, 1, 1) },
1394         { USB_DEVICE_INFO(7, 1, 2) },
1395         { USB_DEVICE_INFO(7, 1, 3) },
1396         { USB_INTERFACE_INFO(7, 1, 1) },
1397         { USB_INTERFACE_INFO(7, 1, 2) },
1398         { USB_INTERFACE_INFO(7, 1, 3) },
1399         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1400         { }                                             /* Terminating entry */
1401 };
1402
1403 MODULE_DEVICE_TABLE(usb, usblp_ids);
1404
1405 static struct usb_driver usblp_driver = {
1406         .name =         "usblp",
1407         .probe =        usblp_probe,
1408         .disconnect =   usblp_disconnect,
1409         .suspend =      usblp_suspend,
1410         .resume =       usblp_resume,
1411         .id_table =     usblp_ids,
1412         .supports_autosuspend = 1,
1413 };
1414
1415 module_usb_driver(usblp_driver);
1416
1417 MODULE_AUTHOR(DRIVER_AUTHOR);
1418 MODULE_DESCRIPTION(DRIVER_DESC);
1419 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1420 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1421 MODULE_LICENSE("GPL");