drivers/usb/class/usblp.c

   1 /*
   2  * usblp.c  Version 0.13
   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/smp_lock.h>
  53 #include <linux/signal.h>
  54 #include <linux/poll.h>
  55 #include <linux/init.h>
  56 #include <linux/slab.h>
  57 #include <linux/lp.h>
  58 #include <linux/mutex.h>
  59 #undef DEBUG
  60 #include <linux/usb.h>
  61
  62 /*
  63  * Version Information
  64  */
  65 #define DRIVER_VERSION "v0.13"
  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_DEVICE_ID_SIZE    1024
  71
  72 /* ioctls: */
  73 #define LPGETSTATUS             0x060b          /* same as in drivers/char/lp.c */
  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_WRITE_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 struct usblp {
 132         struct usb_device       *dev;                   /* USB device */
 133         struct mutex            mut;                    /* locks this struct, especially "dev" */
 134         char                    *writebuf;              /* write transfer_buffer */
 135         char                    *readbuf;               /* read transfer_buffer */
 136         char                    *statusbuf;             /* status transfer_buffer */
 137         struct urb              *readurb, *writeurb;    /* The urbs */
 138         wait_queue_head_t       wait;                   /* Zzzzz ... */
 139         int                     readcount;              /* Counter for reads */
 140         int                     ifnum;                  /* Interface number */
 141         struct usb_interface    *intf;                  /* The interface */
 142         /* Alternate-setting numbers and endpoints for each protocol
 143          * (7/1/{index=1,2,3}) that the device supports: */
 144         struct {
 145                 int                             alt_setting;
 146                 struct usb_endpoint_descriptor  *epwrite;
 147                 struct usb_endpoint_descriptor  *epread;
 148         }                       protocol[USBLP_MAX_PROTOCOLS];
 149         int                     current_protocol;
 150         int                     minor;                  /* minor number of device */
 151         int                     wcomplete;              /* writing is completed */
 152         int                     rcomplete;              /* reading is completed */
 153         unsigned int            quirks;                 /* quirks flags */
 154         unsigned char           used;                   /* True if open */
 155         unsigned char           present;                /* True if not disconnected */
 156         unsigned char           bidir;                  /* interface is bidirectional */
 157         unsigned char           sleeping;               /* interface is suspended */
 158         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 159                                                         /* first 2 bytes are (big-endian) length */
 160 };
 161
 162 #ifdef DEBUG
 163 static void usblp_dump(struct usblp *usblp) {
 164         int p;
 165
 166         dbg("usblp=0x%p", usblp);
 167         dbg("dev=0x%p", usblp->dev);
 168         dbg("present=%d", usblp->present);
 169         dbg("readbuf=0x%p", usblp->readbuf);
 170         dbg("writebuf=0x%p", usblp->writebuf);
 171         dbg("readurb=0x%p", usblp->readurb);
 172         dbg("writeurb=0x%p", usblp->writeurb);
 173         dbg("readcount=%d", usblp->readcount);
 174         dbg("ifnum=%d", usblp->ifnum);
 175     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 176         dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
 177         dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
 178         dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
 179     }
 180         dbg("current_protocol=%d", usblp->current_protocol);
 181         dbg("minor=%d", usblp->minor);
 182         dbg("wcomplete=%d", usblp->wcomplete);
 183         dbg("rcomplete=%d", usblp->rcomplete);
 184         dbg("quirks=%d", usblp->quirks);
 185         dbg("used=%d", usblp->used);
 186         dbg("bidir=%d", usblp->bidir);
 187         dbg("sleeping=%d", usblp->sleeping);
 188         dbg("device_id_string=\"%s\"",
 189                 usblp->device_id_string ?
 190                         usblp->device_id_string + 2 :
 191                         (unsigned char *)"(null)");
 192 }
 193 #endif
 194
 195 /* Quirks: various printer quirks are handled by this table & its flags. */
 196
 197 struct quirk_printer_struct {
 198         __u16 vendorId;
 199         __u16 productId;
 200         unsigned int quirks;
 201 };
 202
 203 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 204 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 205
 206 static const struct quirk_printer_struct quirk_printers[] = {
 207         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 208         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 209         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 210         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 211         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 212         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 213         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 214         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 215         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 216         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 217         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 218         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 219         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 220         { 0, 0 }
 221 };
 222
 223 static int usblp_select_alts(struct usblp *usblp);
 224 static int usblp_set_protocol(struct usblp *usblp, int protocol);
 225 static int usblp_cache_device_id_string(struct usblp *usblp);
 226
 227 /* forward reference to make our lives easier */
 228 static struct usb_driver usblp_driver;
 229 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
 230
 231 /*
 232  * Functions for usblp control messages.
 233  */
 234
 235 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 236 {
 237         int retval;
 238         int index = usblp->ifnum;
 239
 240         /* High byte has the interface index.
 241            Low byte has the alternate setting.
 242          */
 243         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
 244           index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 245         }
 246
 247         retval = usb_control_msg(usblp->dev,
 248                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 249                 request, type | dir | recip, value, index, buf, len, USBLP_WRITE_TIMEOUT);
 250         dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
 251                 request, !!dir, recip, value, index, len, retval);
 252         return retval < 0 ? retval : 0;
 253 }
 254
 255 #define usblp_read_status(usblp, status)\
 256         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 257 #define usblp_get_id(usblp, config, id, maxlen)\
 258         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 259 #define usblp_reset(usblp)\
 260         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 261
 262 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
 263         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
 264
 265 /*
 266  * See the description for usblp_select_alts() below for the usage
 267  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
 268  * case of any trouble.
 269  */
 270 static int proto_bias = -1;
 271
 272 /*
 273  * URB callback.
 274  */
 275
 276 static void usblp_bulk_read(struct urb *urb)
 277 {
 278         struct usblp *usblp = urb->context;
 279
 280         if (unlikely(!usblp || !usblp->dev || !usblp->used))
 281                 return;
 282
 283         if (unlikely(!usblp->present))
 284                 goto unplug;
 285         if (unlikely(urb->status))
 286                 warn("usblp%d: nonzero read/write bulk status received: %d",
 287                         usblp->minor, urb->status);
 288         usblp->rcomplete = 1;
 289 unplug:
 290         wake_up_interruptible(&usblp->wait);
 291 }
 292
 293 static void usblp_bulk_write(struct urb *urb)
 294 {
 295         struct usblp *usblp = urb->context;
 296
 297         if (unlikely(!usblp || !usblp->dev || !usblp->used))
 298                 return;
 299         if (unlikely(!usblp->present))
 300                 goto unplug;
 301         if (unlikely(urb->status))
 302                 warn("usblp%d: nonzero read/write bulk status received: %d",
 303                         usblp->minor, urb->status);
 304         usblp->wcomplete = 1;
 305 unplug:
 306         wake_up_interruptible(&usblp->wait);
 307 }
 308
 309 /*
 310  * Get and print printer errors.
 311  */
 312
 313 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 314
 315 static int usblp_check_status(struct usblp *usblp, int err)
 316 {
 317         unsigned char status, newerr = 0;
 318         int error;
 319
 320         error = usblp_read_status (usblp, usblp->statusbuf);
 321         if (error < 0) {
 322                 if (printk_ratelimit())
 323                         err("usblp%d: error %d reading printer status",
 324                                 usblp->minor, error);
 325                 return 0;
 326         }
 327
 328         status = *usblp->statusbuf;
 329
 330         if (~status & LP_PERRORP)
 331                 newerr = 3;
 332         if (status & LP_POUTPA)
 333                 newerr = 1;
 334         if (~status & LP_PSELECD)
 335                 newerr = 2;
 336
 337         if (newerr != err)
 338                 info("usblp%d: %s", usblp->minor, usblp_messages[newerr]);
 339
 340         return newerr;
 341 }
 342
 343 static int handle_bidir (struct usblp *usblp)
 344 {
 345         if (usblp->bidir && usblp->used && !usblp->sleeping) {
 346                 usblp->readcount = 0;
 347                 usblp->readurb->dev = usblp->dev;
 348                 if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0) {
 349                         usblp->used = 0;
 350                         return -EIO;
 351                 }
 352         }
 353
 354         return 0;
 355 }
 356
 357 /*
 358  * File op functions.
 359  */
 360
 361 static int usblp_open(struct inode *inode, struct file *file)
 362 {
 363         int minor = iminor(inode);
 364         struct usblp *usblp;
 365         struct usb_interface *intf;
 366         int retval;
 367
 368         if (minor < 0)
 369                 return -ENODEV;
 370
 371         mutex_lock (&usblp_mutex);
 372
 373         retval = -ENODEV;
 374         intf = usb_find_interface(&usblp_driver, minor);
 375         if (!intf) {
 376                 goto out;
 377         }
 378         usblp = usb_get_intfdata (intf);
 379         if (!usblp || !usblp->dev || !usblp->present)
 380                 goto out;
 381
 382         retval = -EBUSY;
 383         if (usblp->used)
 384                 goto out;
 385
 386         /*
 387          * TODO: need to implement LP_ABORTOPEN + O_NONBLOCK as in drivers/char/lp.c ???
 388          * This is #if 0-ed because we *don't* want to fail an open
 389          * just because the printer is off-line.
 390          */
 391 #if 0
 392         if ((retval = usblp_check_status(usblp, 0))) {
 393                 retval = retval > 1 ? -EIO : -ENOSPC;
 394                 goto out;
 395         }
 396 #else
 397         retval = 0;
 398 #endif
 399
 400         usblp->used = 1;
 401         file->private_data = usblp;
 402
 403         usblp->writeurb->transfer_buffer_length = 0;
 404         usblp->wcomplete = 1; /* we begin writeable */
 405         usblp->rcomplete = 0;
 406         usblp->writeurb->status = 0;
 407         usblp->readurb->status = 0;
 408
 409         if (handle_bidir(usblp) < 0) {
 410                 file->private_data = NULL;
 411                 retval = -EIO;
 412         }
 413 out:
 414         mutex_unlock (&usblp_mutex);
 415         return retval;
 416 }
 417
 418 static void usblp_cleanup (struct usblp *usblp)
 419 {
 420         info("usblp%d: removed", usblp->minor);
 421
 422         kfree (usblp->device_id_string);
 423         kfree (usblp->statusbuf);
 424         usb_free_urb(usblp->writeurb);
 425         usb_free_urb(usblp->readurb);
 426         kfree (usblp);
 427 }
 428
 429 static void usblp_unlink_urbs(struct usblp *usblp)
 430 {
 431         usb_kill_urb(usblp->writeurb);
 432         if (usblp->bidir)
 433                 usb_kill_urb(usblp->readurb);
 434 }
 435
 436 static int usblp_release(struct inode *inode, struct file *file)
 437 {
 438         struct usblp *usblp = file->private_data;
 439
 440         mutex_lock (&usblp_mutex);
 441         usblp->used = 0;
 442         if (usblp->present) {
 443                 usblp_unlink_urbs(usblp);
 444         } else          /* finish cleanup from disconnect */
 445                 usblp_cleanup (usblp);
 446         mutex_unlock (&usblp_mutex);
 447         return 0;
 448 }
 449
 450 /* No kernel lock - fine */
 451 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
 452 {
 453         struct usblp *usblp = file->private_data;
 454         poll_wait(file, &usblp->wait, wait);
 455         return ((!usblp->bidir || !usblp->rcomplete) ? 0 : POLLIN  | POLLRDNORM)
 456                                | (!usblp->wcomplete ? 0 : POLLOUT | POLLWRNORM);
 457 }
 458
 459 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 460 {
 461         struct usblp *usblp = file->private_data;
 462         int length, err, i;
 463         unsigned char newChannel;
 464         int status;
 465         int twoints[2];
 466         int retval = 0;
 467
 468         mutex_lock (&usblp->mut);
 469         if (!usblp->present) {
 470                 retval = -ENODEV;
 471                 goto done;
 472         }
 473
 474         if (usblp->sleeping) {
 475                 retval = -ENODEV;
 476                 goto done;
 477         }
 478
 479         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
 480                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
 481
 482         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 483
 484                 switch (_IOC_NR(cmd)) {
 485
 486                         case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 487                                 if (_IOC_DIR(cmd) != _IOC_READ) {
 488                                         retval = -EINVAL;
 489                                         goto done;
 490                                 }
 491
 492                                 length = usblp_cache_device_id_string(usblp);
 493                                 if (length < 0) {
 494                                         retval = length;
 495                                         goto done;
 496                                 }
 497                                 if (length > _IOC_SIZE(cmd))
 498                                         length = _IOC_SIZE(cmd); /* truncate */
 499
 500                                 if (copy_to_user((void __user *) arg,
 501                                                 usblp->device_id_string,
 502                                                 (unsigned long) length)) {
 503                                         retval = -EFAULT;
 504                                         goto done;
 505                                 }
 506
 507                                 break;
 508
 509                         case IOCNR_GET_PROTOCOLS:
 510                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 511                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 512                                         retval = -EINVAL;
 513                                         goto done;
 514                                 }
 515
 516                                 twoints[0] = usblp->current_protocol;
 517                                 twoints[1] = 0;
 518                                 for (i = USBLP_FIRST_PROTOCOL;
 519                                      i <= USBLP_LAST_PROTOCOL; i++) {
 520                                         if (usblp->protocol[i].alt_setting >= 0)
 521                                                 twoints[1] |= (1<<i);
 522                                 }
 523
 524                                 if (copy_to_user((void __user *)arg,
 525                                                 (unsigned char *)twoints,
 526                                                 sizeof(twoints))) {
 527                                         retval = -EFAULT;
 528                                         goto done;
 529                                 }
 530
 531                                 break;
 532
 533                         case IOCNR_SET_PROTOCOL:
 534                                 if (_IOC_DIR(cmd) != _IOC_WRITE) {
 535                                         retval = -EINVAL;
 536                                         goto done;
 537                                 }
 538
 539 #ifdef DEBUG
 540                                 if (arg == -10) {
 541                                         usblp_dump(usblp);
 542                                         break;
 543                                 }
 544 #endif
 545
 546                                 usblp_unlink_urbs(usblp);
 547                                 retval = usblp_set_protocol(usblp, arg);
 548                                 if (retval < 0) {
 549                                         usblp_set_protocol(usblp,
 550                                                 usblp->current_protocol);
 551                                 }
 552                                 break;
 553
 554                         case IOCNR_HP_SET_CHANNEL:
 555                                 if (_IOC_DIR(cmd) != _IOC_WRITE ||
 556                                     le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 557                                     usblp->quirks & USBLP_QUIRK_BIDIR) {
 558                                         retval = -EINVAL;
 559                                         goto done;
 560                                 }
 561
 562                                 err = usblp_hp_channel_change_request(usblp,
 563                                         arg, &newChannel);
 564                                 if (err < 0) {
 565                                         err("usblp%d: error = %d setting "
 566                                                 "HP channel",
 567                                                 usblp->minor, err);
 568                                         retval = -EIO;
 569                                         goto done;
 570                                 }
 571
 572                                 dbg("usblp%d requested/got HP channel %ld/%d",
 573                                         usblp->minor, arg, newChannel);
 574                                 break;
 575
 576                         case IOCNR_GET_BUS_ADDRESS:
 577                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 578                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 579                                         retval = -EINVAL;
 580                                         goto done;
 581                                 }
 582
 583                                 twoints[0] = usblp->dev->bus->busnum;
 584                                 twoints[1] = usblp->dev->devnum;
 585                                 if (copy_to_user((void __user *)arg,
 586                                                 (unsigned char *)twoints,
 587                                                 sizeof(twoints))) {
 588                                         retval = -EFAULT;
 589                                         goto done;
 590                                 }
 591
 592                                 dbg("usblp%d is bus=%d, device=%d",
 593                                         usblp->minor, twoints[0], twoints[1]);
 594                                 break;
 595
 596                         case IOCNR_GET_VID_PID:
 597                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 598                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 599                                         retval = -EINVAL;
 600                                         goto done;
 601                                 }
 602
 603                                 twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 604                                 twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 605                                 if (copy_to_user((void __user *)arg,
 606                                                 (unsigned char *)twoints,
 607                                                 sizeof(twoints))) {
 608                                         retval = -EFAULT;
 609                                         goto done;
 610                                 }
 611
 612                                 dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
 613                                         usblp->minor, twoints[0], twoints[1]);
 614                                 break;
 615
 616                         case IOCNR_SOFT_RESET:
 617                                 if (_IOC_DIR(cmd) != _IOC_NONE) {
 618                                         retval = -EINVAL;
 619                                         goto done;
 620                                 }
 621                                 retval = usblp_reset(usblp);
 622                                 break;
 623                         default:
 624                                 retval = -ENOTTY;
 625                 }
 626         else    /* old-style ioctl value */
 627                 switch (cmd) {
 628
 629                         case LPGETSTATUS:
 630                                 if (usblp_read_status(usblp, usblp->statusbuf)) {
 631                                         if (printk_ratelimit())
 632                                                 err("usblp%d: failed reading printer status",
 633                                                         usblp->minor);
 634                                         retval = -EIO;
 635                                         goto done;
 636                                 }
 637                                 status = *usblp->statusbuf;
 638                                 if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
 639                                         retval = -EFAULT;
 640                                 break;
 641
 642                         default:
 643                                 retval = -ENOTTY;
 644                 }
 645
 646 done:
 647         mutex_unlock (&usblp->mut);
 648         return retval;
 649 }
 650
 651 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 652 {
 653         struct usblp *usblp = file->private_data;
 654         int timeout, intr, rv, err = 0, transfer_length = 0;
 655         size_t writecount = 0;
 656
 657         while (writecount < count) {
 658                 if (!usblp->wcomplete) {
 659                         barrier();
 660                         if (file->f_flags & O_NONBLOCK) {
 661                                 writecount += transfer_length;
 662                                 return writecount ? writecount : -EAGAIN;
 663                         }
 664
 665                         timeout = USBLP_WRITE_TIMEOUT;
 666
 667                         rv = wait_event_interruptible_timeout(usblp->wait, usblp->wcomplete || !usblp->present , timeout);
 668                         if (rv < 0)
 669                                 return writecount ? writecount : -EINTR;
 670                 }
 671                 intr = mutex_lock_interruptible (&usblp->mut);
 672                 if (intr)
 673                         return writecount ? writecount : -EINTR;
 674                 if (!usblp->present) {
 675                         mutex_unlock (&usblp->mut);
 676                         return -ENODEV;
 677                 }
 678
 679                 if (usblp->sleeping) {
 680                         mutex_unlock (&usblp->mut);
 681                         return writecount ? writecount : -ENODEV;
 682                 }
 683
 684                 if (usblp->writeurb->status != 0) {
 685                         if (usblp->quirks & USBLP_QUIRK_BIDIR) {
 686                                 if (!usblp->wcomplete)
 687                                         err("usblp%d: error %d writing to printer",
 688                                                 usblp->minor, usblp->writeurb->status);
 689                                 err = usblp->writeurb->status;
 690                         } else
 691                                 err = usblp_check_status(usblp, err);
 692                         mutex_unlock (&usblp->mut);
 693
 694                         /* if the fault was due to disconnect, let khubd's
 695                          * call to usblp_disconnect() grab usblp->mut ...
 696                          */
 697                         schedule ();
 698                         continue;
 699                 }
 700
 701                 /* We must increment writecount here, and not at the
 702                  * end of the loop. Otherwise, the final loop iteration may
 703                  * be skipped, leading to incomplete printer output.
 704                  */
 705                 writecount += transfer_length;
 706                 if (writecount == count) {
 707                         mutex_unlock(&usblp->mut);
 708                         break;
 709                 }
 710
 711                 transfer_length=(count - writecount);
 712                 if (transfer_length > USBLP_BUF_SIZE)
 713                         transfer_length = USBLP_BUF_SIZE;
 714
 715                 usblp->writeurb->transfer_buffer_length = transfer_length;
 716
 717                 if (copy_from_user(usblp->writeurb->transfer_buffer,
 718                                    buffer + writecount, transfer_length)) {
 719                         mutex_unlock(&usblp->mut);
 720                         return writecount ? writecount : -EFAULT;
 721                 }
 722
 723                 usblp->writeurb->dev = usblp->dev;
 724                 usblp->wcomplete = 0;
 725                 err = usb_submit_urb(usblp->writeurb, GFP_KERNEL);
 726                 if (err) {
 727                         usblp->wcomplete = 1;
 728                         if (err != -ENOMEM)
 729                                 count = -EIO;
 730                         else
 731                                 count = writecount ? writecount : -ENOMEM;
 732                         mutex_unlock (&usblp->mut);
 733                         break;
 734                 }
 735                 mutex_unlock (&usblp->mut);
 736         }
 737
 738         return count;
 739 }
 740
 741 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
 742 {
 743         struct usblp *usblp = file->private_data;
 744         int rv, intr;
 745
 746         if (!usblp->bidir)
 747                 return -EINVAL;
 748
 749         intr = mutex_lock_interruptible (&usblp->mut);
 750         if (intr)
 751                 return -EINTR;
 752         if (!usblp->present) {
 753                 count = -ENODEV;
 754                 goto done;
 755         }
 756
 757         if (!usblp->rcomplete) {
 758                 barrier();
 759
 760                 if (file->f_flags & O_NONBLOCK) {
 761                         count = -EAGAIN;
 762                         goto done;
 763                 }
 764                 mutex_unlock(&usblp->mut);
 765                 rv = wait_event_interruptible(usblp->wait, usblp->rcomplete || !usblp->present);
 766                 mutex_lock(&usblp->mut);
 767                 if (rv < 0) {
 768                         count = -EINTR;
 769                         goto done;
 770                 }
 771         }
 772
 773         if (!usblp->present) {
 774                 count = -ENODEV;
 775                 goto done;
 776         }
 777
 778         if (usblp->sleeping) {
 779                 count = -ENODEV;
 780                 goto done;
 781         }
 782
 783         if (usblp->readurb->status) {
 784                 err("usblp%d: error %d reading from printer",
 785                         usblp->minor, usblp->readurb->status);
 786                 usblp->readurb->dev = usblp->dev;
 787                 usblp->readcount = 0;
 788                 usblp->rcomplete = 0;
 789                 if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0)
 790                         dbg("error submitting urb");
 791                 count = -EIO;
 792                 goto done;
 793         }
 794
 795         count = count < usblp->readurb->actual_length - usblp->readcount ?
 796                 count : usblp->readurb->actual_length - usblp->readcount;
 797
 798         if (copy_to_user(buffer, usblp->readurb->transfer_buffer + usblp->readcount, count)) {
 799                 count = -EFAULT;
 800                 goto done;
 801         }
 802
 803         if ((usblp->readcount += count) == usblp->readurb->actual_length) {
 804                 usblp->readcount = 0;
 805                 usblp->readurb->dev = usblp->dev;
 806                 usblp->rcomplete = 0;
 807                 if (usb_submit_urb(usblp->readurb, GFP_KERNEL)) {
 808                         count = -EIO;
 809                         goto done;
 810                 }
 811         }
 812
 813 done:
 814         mutex_unlock (&usblp->mut);
 815         return count;
 816 }
 817
 818 /*
 819  * Checks for printers that have quirks, such as requiring unidirectional
 820  * communication but reporting bidirectional; currently some HP printers
 821  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
 822  * sent at each open (like some Epsons).
 823  * Returns 1 if found, 0 if not found.
 824  *
 825  * HP recommended that we use the bidirectional interface but
 826  * don't attempt any bulk IN transfers from the IN endpoint.
 827  * Here's some more detail on the problem:
 828  * The problem is not that it isn't bidirectional though. The problem
 829  * is that if you request a device ID, or status information, while
 830  * the buffers are full, the return data will end up in the print data
 831  * buffer. For example if you make sure you never request the device ID
 832  * while you are sending print data, and you don't try to query the
 833  * printer status every couple of milliseconds, you will probably be OK.
 834  */
 835 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
 836 {
 837         int i;
 838
 839         for (i = 0; quirk_printers[i].vendorId; i++) {
 840                 if (vendor == quirk_printers[i].vendorId &&
 841                     product == quirk_printers[i].productId)
 842                         return quirk_printers[i].quirks;
 843         }
 844         return 0;
 845 }
 846
 847 static const struct file_operations usblp_fops = {
 848         .owner =        THIS_MODULE,
 849         .read =         usblp_read,
 850         .write =        usblp_write,
 851         .poll =         usblp_poll,
 852         .unlocked_ioctl =       usblp_ioctl,
 853         .compat_ioctl =         usblp_ioctl,
 854         .open =         usblp_open,
 855         .release =      usblp_release,
 856 };
 857
 858 static struct usb_class_driver usblp_class = {
 859         .name =         "lp%d",
 860         .fops =         &usblp_fops,
 861         .minor_base =   USBLP_MINOR_BASE,
 862 };
 863
 864 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
 865 {
 866         struct usb_interface *intf = to_usb_interface(dev);
 867         struct usblp *usblp = usb_get_intfdata (intf);
 868
 869         if (usblp->device_id_string[0] == 0 &&
 870             usblp->device_id_string[1] == 0)
 871                 return 0;
 872
 873         return sprintf(buf, "%s", usblp->device_id_string+2);
 874 }
 875
 876 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
 877
 878 static int usblp_probe(struct usb_interface *intf,
 879                        const struct usb_device_id *id)
 880 {
 881         struct usb_device *dev = interface_to_usbdev (intf);
 882         struct usblp *usblp = NULL;
 883         int protocol;
 884         int retval;
 885
 886         /* Malloc and start initializing usblp structure so we can use it
 887          * directly. */
 888         if (!(usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL))) {
 889                 err("out of memory for usblp");
 890                 goto abort;
 891         }
 892         usblp->dev = dev;
 893         mutex_init (&usblp->mut);
 894         init_waitqueue_head(&usblp->wait);
 895         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
 896         usblp->intf = intf;
 897
 898         usblp->writeurb = usb_alloc_urb(0, GFP_KERNEL);
 899         if (!usblp->writeurb) {
 900                 err("out of memory");
 901                 goto abort;
 902         }
 903         usblp->readurb = usb_alloc_urb(0, GFP_KERNEL);
 904         if (!usblp->readurb) {
 905                 err("out of memory");
 906                 goto abort;
 907         }
 908
 909         /* Malloc device ID string buffer to the largest expected length,
 910          * since we can re-query it on an ioctl and a dynamic string
 911          * could change in length. */
 912         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
 913                 err("out of memory for device_id_string");
 914                 goto abort;
 915         }
 916
 917         usblp->writebuf = usblp->readbuf = NULL;
 918         usblp->writeurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
 919         usblp->readurb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
 920         /* Malloc write & read buffers.  We somewhat wastefully
 921          * malloc both regardless of bidirectionality, because the
 922          * alternate setting can be changed later via an ioctl. */
 923         if (!(usblp->writebuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
 924                                 GFP_KERNEL, &usblp->writeurb->transfer_dma))) {
 925                 err("out of memory for write buf");
 926                 goto abort;
 927         }
 928         if (!(usblp->readbuf = usb_buffer_alloc(dev, USBLP_BUF_SIZE,
 929                                 GFP_KERNEL, &usblp->readurb->transfer_dma))) {
 930                 err("out of memory for read buf");
 931                 goto abort;
 932         }
 933
 934         /* Allocate buffer for printer status */
 935         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
 936         if (!usblp->statusbuf) {
 937                 err("out of memory for statusbuf");
 938                 goto abort;
 939         }
 940
 941         /* Lookup quirks for this printer. */
 942         usblp->quirks = usblp_quirks(
 943                 le16_to_cpu(dev->descriptor.idVendor),
 944                 le16_to_cpu(dev->descriptor.idProduct));
 945
 946         /* Analyze and pick initial alternate settings and endpoints. */
 947         protocol = usblp_select_alts(usblp);
 948         if (protocol < 0) {
 949                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
 950                         le16_to_cpu(dev->descriptor.idVendor),
 951                         le16_to_cpu(dev->descriptor.idProduct));
 952                 goto abort;
 953         }
 954
 955         /* Setup the selected alternate setting and endpoints. */
 956         if (usblp_set_protocol(usblp, protocol) < 0)
 957                 goto abort;
 958
 959         /* Retrieve and store the device ID string. */
 960         usblp_cache_device_id_string(usblp);
 961         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
 962         if (retval)
 963                 goto abort_intfdata;
 964
 965 #ifdef DEBUG
 966         usblp_check_status(usblp, 0);
 967 #endif
 968
 969         usb_set_intfdata (intf, usblp);
 970
 971         usblp->present = 1;
 972
 973         retval = usb_register_dev(intf, &usblp_class);
 974         if (retval) {
 975                 err("Not able to get a minor for this device.");
 976                 goto abort_intfdata;
 977         }
 978         usblp->minor = intf->minor;
 979         info("usblp%d: USB %sdirectional printer dev %d "
 980                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X",
 981                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
 982                 usblp->ifnum,
 983                 usblp->protocol[usblp->current_protocol].alt_setting,
 984                 usblp->current_protocol,
 985                 le16_to_cpu(usblp->dev->descriptor.idVendor),
 986                 le16_to_cpu(usblp->dev->descriptor.idProduct));
 987
 988         return 0;
 989
 990 abort_intfdata:
 991         usb_set_intfdata (intf, NULL);
 992         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
 993 abort:
 994         if (usblp) {
 995                 if (usblp->writebuf)
 996                         usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
 997                                 usblp->writebuf, usblp->writeurb->transfer_dma);
 998                 if (usblp->readbuf)
 999                         usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1000                                 usblp->readbuf, usblp->writeurb->transfer_dma);
1001                 kfree(usblp->statusbuf);
1002                 kfree(usblp->device_id_string);
1003                 usb_free_urb(usblp->writeurb);
1004                 usb_free_urb(usblp->readurb);
1005                 kfree(usblp);
1006         }
1007         return -EIO;
1008 }
1009
1010 /*
1011  * We are a "new" style driver with usb_device_id table,
1012  * but our requirements are too intricate for simple match to handle.
1013  *
1014  * The "proto_bias" option may be used to specify the preferred protocol
1015  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1016  * supports the preferred protocol, then we bind to it.
1017  *
1018  * The best interface for us is 7/1/2, because it is compatible
1019  * with a stream of characters. If we find it, we bind to it.
1020  *
1021  * Note that the people from hpoj.sourceforge.net need to be able to
1022  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1023  *
1024  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1025  * stream-compatible, because this matches the behaviour of the old code.
1026  *
1027  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1028  */
1029 static int usblp_select_alts(struct usblp *usblp)
1030 {
1031         struct usb_interface *if_alt;
1032         struct usb_host_interface *ifd;
1033         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1034         int p, i, e;
1035
1036         if_alt = usblp->intf;
1037
1038         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1039                 usblp->protocol[p].alt_setting = -1;
1040
1041         /* Find out what we have. */
1042         for (i = 0; i < if_alt->num_altsetting; i++) {
1043                 ifd = &if_alt->altsetting[i];
1044
1045                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1046                         continue;
1047
1048                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1049                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1050                         continue;
1051
1052                 /* Look for bulk OUT and IN endpoints. */
1053                 epwrite = epread = NULL;
1054                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1055                         epd = &ifd->endpoint[e].desc;
1056
1057                         if (usb_endpoint_is_bulk_out(epd))
1058                                 if (!epwrite)
1059                                         epwrite = epd;
1060
1061                         if (usb_endpoint_is_bulk_in(epd))
1062                                 if (!epread)
1063                                         epread = epd;
1064                 }
1065
1066                 /* Ignore buggy hardware without the right endpoints. */
1067                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1068                         continue;
1069
1070                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1071                  * and buggy bidirectional printers. */
1072                 if (ifd->desc.bInterfaceProtocol == 1) {
1073                         epread = NULL;
1074                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1075                         info("Disabling reads from problem bidirectional "
1076                                 "printer on usblp%d", usblp->minor);
1077                         epread = NULL;
1078                 }
1079
1080                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1081                                 ifd->desc.bAlternateSetting;
1082                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1083                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1084         }
1085
1086         /* If our requested protocol is supported, then use it. */
1087         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1088             proto_bias <= USBLP_LAST_PROTOCOL &&
1089             usblp->protocol[proto_bias].alt_setting != -1)
1090                 return proto_bias;
1091
1092         /* Ordering is important here. */
1093         if (usblp->protocol[2].alt_setting != -1)
1094                 return 2;
1095         if (usblp->protocol[1].alt_setting != -1)
1096                 return 1;
1097         if (usblp->protocol[3].alt_setting != -1)
1098                 return 3;
1099
1100         /* If nothing is available, then don't bind to this device. */
1101         return -1;
1102 }
1103
1104 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1105 {
1106         int r, alts;
1107
1108         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1109                 return -EINVAL;
1110
1111         alts = usblp->protocol[protocol].alt_setting;
1112         if (alts < 0)
1113                 return -EINVAL;
1114         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1115         if (r < 0) {
1116                 err("can't set desired altsetting %d on interface %d",
1117                         alts, usblp->ifnum);
1118                 return r;
1119         }
1120
1121         usb_fill_bulk_urb(usblp->writeurb, usblp->dev,
1122                 usb_sndbulkpipe(usblp->dev,
1123                   usblp->protocol[protocol].epwrite->bEndpointAddress),
1124                 usblp->writebuf, 0,
1125                 usblp_bulk_write, usblp);
1126
1127         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1128         if (usblp->bidir)
1129                 usb_fill_bulk_urb(usblp->readurb, usblp->dev,
1130                         usb_rcvbulkpipe(usblp->dev,
1131                           usblp->protocol[protocol].epread->bEndpointAddress),
1132                         usblp->readbuf, USBLP_BUF_SIZE,
1133                         usblp_bulk_read, usblp);
1134
1135         usblp->current_protocol = protocol;
1136         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1137         return 0;
1138 }
1139
1140 /* Retrieves and caches device ID string.
1141  * Returns length, including length bytes but not null terminator.
1142  * On error, returns a negative errno value. */
1143 static int usblp_cache_device_id_string(struct usblp *usblp)
1144 {
1145         int err, length;
1146
1147         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1148         if (err < 0) {
1149                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1150                         usblp->minor, err);
1151                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1152                 return -EIO;
1153         }
1154
1155         /* First two bytes are length in big-endian.
1156          * They count themselves, and we copy them into
1157          * the user's buffer. */
1158         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1159         if (length < 2)
1160                 length = 2;
1161         else if (length >= USBLP_DEVICE_ID_SIZE)
1162                 length = USBLP_DEVICE_ID_SIZE - 1;
1163         usblp->device_id_string[length] = '\0';
1164
1165         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1166                 usblp->minor, length, &usblp->device_id_string[2]);
1167
1168         return length;
1169 }
1170
1171 static void usblp_disconnect(struct usb_interface *intf)
1172 {
1173         struct usblp *usblp = usb_get_intfdata (intf);
1174
1175         usb_deregister_dev(intf, &usblp_class);
1176
1177         if (!usblp || !usblp->dev) {
1178                 err("bogus disconnect");
1179                 BUG ();
1180         }
1181
1182         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1183
1184         mutex_lock (&usblp_mutex);
1185         mutex_lock (&usblp->mut);
1186         usblp->present = 0;
1187         usb_set_intfdata (intf, NULL);
1188
1189         usblp_unlink_urbs(usblp);
1190         usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1191                         usblp->writebuf, usblp->writeurb->transfer_dma);
1192         usb_buffer_free (usblp->dev, USBLP_BUF_SIZE,
1193                         usblp->readbuf, usblp->readurb->transfer_dma);
1194         mutex_unlock (&usblp->mut);
1195
1196         if (!usblp->used)
1197                 usblp_cleanup (usblp);
1198         mutex_unlock (&usblp_mutex);
1199 }
1200
1201 static int usblp_suspend (struct usb_interface *intf, pm_message_t message)
1202 {
1203         struct usblp *usblp = usb_get_intfdata (intf);
1204
1205         /* this races against normal access and open */
1206         mutex_lock (&usblp_mutex);
1207         mutex_lock (&usblp->mut);
1208         /* we take no more IO */
1209         usblp->sleeping = 1;
1210         usblp_unlink_urbs(usblp);
1211         mutex_unlock (&usblp->mut);
1212         mutex_unlock (&usblp_mutex);
1213
1214         return 0;
1215 }
1216
1217 static int usblp_resume (struct usb_interface *intf)
1218 {
1219         struct usblp *usblp = usb_get_intfdata (intf);
1220         int r;
1221
1222         mutex_lock (&usblp_mutex);
1223         mutex_lock (&usblp->mut);
1224
1225         usblp->sleeping = 0;
1226         r = handle_bidir (usblp);
1227
1228         mutex_unlock (&usblp->mut);
1229         mutex_unlock (&usblp_mutex);
1230
1231         return r;
1232 }
1233
1234 static struct usb_device_id usblp_ids [] = {
1235         { USB_DEVICE_INFO(7, 1, 1) },
1236         { USB_DEVICE_INFO(7, 1, 2) },
1237         { USB_DEVICE_INFO(7, 1, 3) },
1238         { USB_INTERFACE_INFO(7, 1, 1) },
1239         { USB_INTERFACE_INFO(7, 1, 2) },
1240         { USB_INTERFACE_INFO(7, 1, 3) },
1241         { }                                             /* Terminating entry */
1242 };
1243
1244 MODULE_DEVICE_TABLE (usb, usblp_ids);
1245
1246 static struct usb_driver usblp_driver = {
1247         .name =         "usblp",
1248         .probe =        usblp_probe,
1249         .disconnect =   usblp_disconnect,
1250         .suspend =      usblp_suspend,
1251         .resume =       usblp_resume,
1252         .id_table =     usblp_ids,
1253 };
1254
1255 static int __init usblp_init(void)
1256 {
1257         int retval;
1258         retval = usb_register(&usblp_driver);
1259         if (!retval)
1260                 info(DRIVER_VERSION ": " DRIVER_DESC);
1261
1262         return retval;
1263 }
1264
1265 static void __exit usblp_exit(void)
1266 {
1267         usb_deregister(&usblp_driver);
1268 }
1269
1270 module_init(usblp_init);
1271 module_exit(usblp_exit);
1272
1273 MODULE_AUTHOR( DRIVER_AUTHOR );
1274 MODULE_DESCRIPTION( DRIVER_DESC );
1275 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1276 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1277 MODULE_LICENSE("GPL");