git.oblomov.eu Git - linux-2.6/blob - drivers/usb/class/usblp.c

   1 /*
   2  * usblp.c
   3  *
   4  * Copyright (c) 1999 Michael Gee       <michael@linuxspecific.com>
   5  * Copyright (c) 1999 Pavel Machek      <pavel@suse.cz>
   6  * Copyright (c) 2000 Randy Dunlap      <rdunlap@xenotime.net>
   7  * Copyright (c) 2000 Vojtech Pavlik    <vojtech@suse.cz>
   8  # Copyright (c) 2001 Pete Zaitcev      <zaitcev@redhat.com>
   9  # Copyright (c) 2001 David Paschal     <paschal@rcsis.com>
  10  * Copyright (c) 2006 Oliver Neukum     <oliver@neukum.name>
  11  *
  12  * USB Printer Device Class driver for USB printers and printer cables
  13  *
  14  * Sponsored by SuSE
  15  *
  16  * ChangeLog:
  17  *      v0.1 - thorough cleaning, URBification, almost a rewrite
  18  *      v0.2 - some more cleanups
  19  *      v0.3 - cleaner again, waitqueue fixes
  20  *      v0.4 - fixes in unidirectional mode
  21  *      v0.5 - add DEVICE_ID string support
  22  *      v0.6 - never time out
  23  *      v0.7 - fixed bulk-IN read and poll (David Paschal)
  24  *      v0.8 - add devfs support
  25  *      v0.9 - fix unplug-while-open paths
  26  *      v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
  27  *      v0.11 - add proto_bias option (Pete Zaitcev)
  28  *      v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
  29  *      v0.13 - alloc space for statusbuf (<status> not on stack);
  30  *              use usb_buffer_alloc() for read buf & write buf;
  31  *      none  - Maintained in Linux kernel after v0.13
  32  */
  33
  34 /*
  35  * This program is free software; you can redistribute it and/or modify
  36  * it under the terms of the GNU General Public License as published by
  37  * the Free Software Foundation; either version 2 of the License, or
  38  * (at your option) any later version.
  39  *
  40  * This program is distributed in the hope that it will be useful,
  41  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  42  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  43  * GNU General Public License for more details.
  44  *
  45  * You should have received a copy of the GNU General Public License
  46  * along with this program; if not, write to the Free Software
  47  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  48  */
  49
  50 #include <linux/module.h>
  51 #include <linux/kernel.h>
  52 #include <linux/sched.h>
  53 #include <linux/signal.h>
  54 #include <linux/poll.h>
  55 #include <linux/init.h>
  56 #include <linux/slab.h>
  57 #include <linux/lp.h>
  58 #include <linux/mutex.h>
  59 #undef DEBUG
  60 #include <linux/usb.h>
  61
  62 /*
  63  * Version Information
  64  */
  65 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  66 #define DRIVER_DESC "USB Printer Device Class driver"
  67
  68 #define USBLP_BUF_SIZE          8192
  69 #define USBLP_BUF_SIZE_IN       1024
  70 #define USBLP_DEVICE_ID_SIZE    1024
  71
  72 /* ioctls: */
  73 #define IOCNR_GET_DEVICE_ID             1
  74 #define IOCNR_GET_PROTOCOLS             2
  75 #define IOCNR_SET_PROTOCOL              3
  76 #define IOCNR_HP_SET_CHANNEL            4
  77 #define IOCNR_GET_BUS_ADDRESS           5
  78 #define IOCNR_GET_VID_PID               6
  79 #define IOCNR_SOFT_RESET                7
  80 /* Get device_id string: */
  81 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  82 /* The following ioctls were added for http://hpoj.sourceforge.net: */
  83 /* Get two-int array:
  84  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
  85  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
  86 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  87 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
  88 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  89 /* Set channel number (HP Vendor-specific command): */
  90 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
  91 /* Get two-int array: [0]=bus number, [1]=device address: */
  92 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
  93 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
  94 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
  95 /* Perform class specific soft reset */
  96 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
  97
  98 /*
  99  * A DEVICE_ID string may include the printer's serial number.
 100  * It should end with a semi-colon (';').
 101  * An example from an HP 970C DeskJet printer is (this is one long string,
 102  * with the serial number changed):
 103 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
 104  */
 105
 106 /*
 107  * USB Printer Requests
 108  */
 109
 110 #define USBLP_REQ_GET_ID                        0x00
 111 #define USBLP_REQ_GET_STATUS                    0x01
 112 #define USBLP_REQ_RESET                         0x02
 113 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
 114
 115 #define USBLP_MINORS            16
 116 #define USBLP_MINOR_BASE        0
 117
 118 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
 119
 120 #define USBLP_FIRST_PROTOCOL    1
 121 #define USBLP_LAST_PROTOCOL     3
 122 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
 123
 124 /*
 125  * some arbitrary status buffer size;
 126  * need a status buffer that is allocated via kmalloc(), not on stack
 127  */
 128 #define STATUS_BUF_SIZE         8
 129
 130 /*
 131  * Locks down the locking order:
 132  * ->wmut locks wstatus.
 133  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 134  * [rw]status. We only touch status when we know the side idle.
 135  * ->lock locks what interrupt accesses.
 136  */
 137 struct usblp {
 138         struct usb_device       *dev;                   /* USB device */
 139         struct mutex            wmut;
 140         struct mutex            mut;
 141         spinlock_t              lock;           /* locks rcomplete, wcomplete */
 142         char                    *readbuf;               /* read transfer_buffer */
 143         char                    *statusbuf;             /* status transfer_buffer */
 144         struct usb_anchor       urbs;
 145         wait_queue_head_t       rwait, wwait;
 146         int                     readcount;              /* Counter for reads */
 147         int                     ifnum;                  /* Interface number */
 148         struct usb_interface    *intf;                  /* The interface */
 149         /* Alternate-setting numbers and endpoints for each protocol
 150          * (7/1/{index=1,2,3}) that the device supports: */
 151         struct {
 152                 int                             alt_setting;
 153                 struct usb_endpoint_descriptor  *epwrite;
 154                 struct usb_endpoint_descriptor  *epread;
 155         }                       protocol[USBLP_MAX_PROTOCOLS];
 156         int                     current_protocol;
 157         int                     minor;                  /* minor number of device */
 158         int                     wcomplete, rcomplete;
 159         int                     wstatus;        /* bytes written or error */
 160         int                     rstatus;        /* bytes ready or error */
 161         unsigned int            quirks;                 /* quirks flags */
 162         unsigned int            flags;                  /* mode flags */
 163         unsigned char           used;                   /* True if open */
 164         unsigned char           present;                /* True if not disconnected */
 165         unsigned char           bidir;                  /* interface is bidirectional */
 166         unsigned char           sleeping;               /* interface is suspended */
 167         unsigned char           no_paper;               /* Paper Out happened */
 168         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 169                                                         /* first 2 bytes are (big-endian) length */
 170 };
 171
 172 #ifdef DEBUG
 173 static void usblp_dump(struct usblp *usblp) {
 174         int p;
 175
 176         dbg("usblp=0x%p", usblp);
 177         dbg("dev=0x%p", usblp->dev);
 178         dbg("present=%d", usblp->present);
 179         dbg("readbuf=0x%p", usblp->readbuf);
 180         dbg("readcount=%d", usblp->readcount);
 181         dbg("ifnum=%d", usblp->ifnum);
 182     for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 183         dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
 184         dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
 185         dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
 186     }
 187         dbg("current_protocol=%d", usblp->current_protocol);
 188         dbg("minor=%d", usblp->minor);
 189         dbg("wstatus=%d", usblp->wstatus);
 190         dbg("rstatus=%d", usblp->rstatus);
 191         dbg("quirks=%d", usblp->quirks);
 192         dbg("used=%d", usblp->used);
 193         dbg("bidir=%d", usblp->bidir);
 194         dbg("sleeping=%d", usblp->sleeping);
 195         dbg("device_id_string=\"%s\"",
 196                 usblp->device_id_string ?
 197                         usblp->device_id_string + 2 :
 198                         (unsigned char *)"(null)");
 199 }
 200 #endif
 201
 202 /* Quirks: various printer quirks are handled by this table & its flags. */
 203
 204 struct quirk_printer_struct {
 205         __u16 vendorId;
 206         __u16 productId;
 207         unsigned int quirks;
 208 };
 209
 210 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 211 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 212 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
 213
 214 static const struct quirk_printer_struct quirk_printers[] = {
 215         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 216         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 217         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 218         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 219         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 220         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 221         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 222         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 223         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 224         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 225         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 226         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 227         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 228         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
 229         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 230         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
 231         { 0, 0 }
 232 };
 233
 234 static int usblp_wwait(struct usblp *usblp, int nonblock);
 235 static int usblp_wtest(struct usblp *usblp, int nonblock);
 236 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
 237 static int usblp_rtest(struct usblp *usblp, int nonblock);
 238 static int usblp_submit_read(struct usblp *usblp);
 239 static int usblp_select_alts(struct usblp *usblp);
 240 static int usblp_set_protocol(struct usblp *usblp, int protocol);
 241 static int usblp_cache_device_id_string(struct usblp *usblp);
 242
 243 /* forward reference to make our lives easier */
 244 static struct usb_driver usblp_driver;
 245 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
 246
 247 /*
 248  * Functions for usblp control messages.
 249  */
 250
 251 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 252 {
 253         int retval;
 254         int index = usblp->ifnum;
 255
 256         /* High byte has the interface index.
 257            Low byte has the alternate setting.
 258          */
 259         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS)) {
 260           index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 261         }
 262
 263         retval = usb_control_msg(usblp->dev,
 264                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 265                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
 266         dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
 267                 request, !!dir, recip, value, index, len, retval);
 268         return retval < 0 ? retval : 0;
 269 }
 270
 271 #define usblp_read_status(usblp, status)\
 272         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 273 #define usblp_get_id(usblp, config, id, maxlen)\
 274         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 275 #define usblp_reset(usblp)\
 276         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 277
 278 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
 279         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
 280
 281 /*
 282  * See the description for usblp_select_alts() below for the usage
 283  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
 284  * case of any trouble.
 285  */
 286 static int proto_bias = -1;
 287
 288 /*
 289  * URB callback.
 290  */
 291
 292 static void usblp_bulk_read(struct urb *urb)
 293 {
 294         struct usblp *usblp = urb->context;
 295         int status = urb->status;
 296
 297         if (usblp->present && usblp->used) {
 298                 if (status)
 299                         printk(KERN_WARNING "usblp%d: "
 300                             "nonzero read bulk status received: %d\n",
 301                             usblp->minor, status);
 302         }
 303         spin_lock(&usblp->lock);
 304         if (status < 0)
 305                 usblp->rstatus = status;
 306         else
 307                 usblp->rstatus = urb->actual_length;
 308         usblp->rcomplete = 1;
 309         wake_up(&usblp->rwait);
 310         spin_unlock(&usblp->lock);
 311
 312         usb_free_urb(urb);
 313 }
 314
 315 static void usblp_bulk_write(struct urb *urb)
 316 {
 317         struct usblp *usblp = urb->context;
 318         int status = urb->status;
 319
 320         if (usblp->present && usblp->used) {
 321                 if (status)
 322                         printk(KERN_WARNING "usblp%d: "
 323                             "nonzero write bulk status received: %d\n",
 324                             usblp->minor, status);
 325         }
 326         spin_lock(&usblp->lock);
 327         if (status < 0)
 328                 usblp->wstatus = status;
 329         else
 330                 usblp->wstatus = urb->actual_length;
 331         usblp->no_paper = 0;
 332         usblp->wcomplete = 1;
 333         wake_up(&usblp->wwait);
 334         spin_unlock(&usblp->lock);
 335
 336         usb_free_urb(urb);
 337 }
 338
 339 /*
 340  * Get and print printer errors.
 341  */
 342
 343 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 344
 345 static int usblp_check_status(struct usblp *usblp, int err)
 346 {
 347         unsigned char status, newerr = 0;
 348         int error;
 349
 350         mutex_lock(&usblp->mut);
 351         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 352                 mutex_unlock(&usblp->mut);
 353                 if (printk_ratelimit())
 354                         printk(KERN_ERR
 355                                 "usblp%d: error %d reading printer status\n",
 356                                 usblp->minor, error);
 357                 return 0;
 358         }
 359         status = *usblp->statusbuf;
 360         mutex_unlock(&usblp->mut);
 361
 362         if (~status & LP_PERRORP)
 363                 newerr = 3;
 364         if (status & LP_POUTPA)
 365                 newerr = 1;
 366         if (~status & LP_PSELECD)
 367                 newerr = 2;
 368
 369         if (newerr != err) {
 370                 printk(KERN_INFO "usblp%d: %s\n",
 371                    usblp->minor, usblp_messages[newerr]);
 372         }
 373
 374         return newerr;
 375 }
 376
 377 static int handle_bidir (struct usblp *usblp)
 378 {
 379         if (usblp->bidir && usblp->used && !usblp->sleeping) {
 380                 if (usblp_submit_read(usblp) < 0)
 381                         return -EIO;
 382         }
 383         return 0;
 384 }
 385
 386 /*
 387  * File op functions.
 388  */
 389
 390 static int usblp_open(struct inode *inode, struct file *file)
 391 {
 392         int minor = iminor(inode);
 393         struct usblp *usblp;
 394         struct usb_interface *intf;
 395         int retval;
 396
 397         if (minor < 0)
 398                 return -ENODEV;
 399
 400         mutex_lock (&usblp_mutex);
 401
 402         retval = -ENODEV;
 403         intf = usb_find_interface(&usblp_driver, minor);
 404         if (!intf) {
 405                 goto out;
 406         }
 407         usblp = usb_get_intfdata (intf);
 408         if (!usblp || !usblp->dev || !usblp->present)
 409                 goto out;
 410
 411         retval = -EBUSY;
 412         if (usblp->used)
 413                 goto out;
 414
 415         /*
 416          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 417          *  - We do not want persistent state which close(2) does not clear
 418          *  - It is not used anyway, according to CUPS people
 419          */
 420
 421         retval = usb_autopm_get_interface(intf);
 422         if (retval < 0)
 423                 goto out;
 424         usblp->used = 1;
 425         file->private_data = usblp;
 426
 427         usblp->wcomplete = 1; /* we begin writeable */
 428         usblp->wstatus = 0;
 429         usblp->rcomplete = 0;
 430
 431         if (handle_bidir(usblp) < 0) {
 432                 usb_autopm_put_interface(intf);
 433                 usblp->used = 0;
 434                 file->private_data = NULL;
 435                 retval = -EIO;
 436         }
 437 out:
 438         mutex_unlock (&usblp_mutex);
 439         return retval;
 440 }
 441
 442 static void usblp_cleanup (struct usblp *usblp)
 443 {
 444         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 445
 446         kfree(usblp->readbuf);
 447         kfree (usblp->device_id_string);
 448         kfree (usblp->statusbuf);
 449         kfree (usblp);
 450 }
 451
 452 static void usblp_unlink_urbs(struct usblp *usblp)
 453 {
 454         usb_kill_anchored_urbs(&usblp->urbs);
 455 }
 456
 457 static int usblp_release(struct inode *inode, struct file *file)
 458 {
 459         struct usblp *usblp = file->private_data;
 460
 461         usblp->flags &= ~LP_ABORT;
 462
 463         mutex_lock (&usblp_mutex);
 464         usblp->used = 0;
 465         if (usblp->present) {
 466                 usblp_unlink_urbs(usblp);
 467                 usb_autopm_put_interface(usblp->intf);
 468         } else          /* finish cleanup from disconnect */
 469                 usblp_cleanup (usblp);
 470         mutex_unlock (&usblp_mutex);
 471         return 0;
 472 }
 473
 474 /* No kernel lock - fine */
 475 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
 476 {
 477         int ret;
 478         unsigned long flags;
 479
 480         struct usblp *usblp = file->private_data;
 481         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 482         poll_wait(file, &usblp->rwait, wait);
 483         poll_wait(file, &usblp->wwait, wait);
 484         spin_lock_irqsave(&usblp->lock, flags);
 485         ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
 486            ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
 487         spin_unlock_irqrestore(&usblp->lock, flags);
 488         return ret;
 489 }
 490
 491 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 492 {
 493         struct usblp *usblp = file->private_data;
 494         int length, err, i;
 495         unsigned char newChannel;
 496         int status;
 497         int twoints[2];
 498         int retval = 0;
 499
 500         mutex_lock (&usblp->mut);
 501         if (!usblp->present) {
 502                 retval = -ENODEV;
 503                 goto done;
 504         }
 505
 506         if (usblp->sleeping) {
 507                 retval = -ENODEV;
 508                 goto done;
 509         }
 510
 511         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
 512                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
 513
 514         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 515
 516                 switch (_IOC_NR(cmd)) {
 517
 518                         case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 519                                 if (_IOC_DIR(cmd) != _IOC_READ) {
 520                                         retval = -EINVAL;
 521                                         goto done;
 522                                 }
 523
 524                                 length = usblp_cache_device_id_string(usblp);
 525                                 if (length < 0) {
 526                                         retval = length;
 527                                         goto done;
 528                                 }
 529                                 if (length > _IOC_SIZE(cmd))
 530                                         length = _IOC_SIZE(cmd); /* truncate */
 531
 532                                 if (copy_to_user((void __user *) arg,
 533                                                 usblp->device_id_string,
 534                                                 (unsigned long) length)) {
 535                                         retval = -EFAULT;
 536                                         goto done;
 537                                 }
 538
 539                                 break;
 540
 541                         case IOCNR_GET_PROTOCOLS:
 542                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 543                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 544                                         retval = -EINVAL;
 545                                         goto done;
 546                                 }
 547
 548                                 twoints[0] = usblp->current_protocol;
 549                                 twoints[1] = 0;
 550                                 for (i = USBLP_FIRST_PROTOCOL;
 551                                      i <= USBLP_LAST_PROTOCOL; i++) {
 552                                         if (usblp->protocol[i].alt_setting >= 0)
 553                                                 twoints[1] |= (1<<i);
 554                                 }
 555
 556                                 if (copy_to_user((void __user *)arg,
 557                                                 (unsigned char *)twoints,
 558                                                 sizeof(twoints))) {
 559                                         retval = -EFAULT;
 560                                         goto done;
 561                                 }
 562
 563                                 break;
 564
 565                         case IOCNR_SET_PROTOCOL:
 566                                 if (_IOC_DIR(cmd) != _IOC_WRITE) {
 567                                         retval = -EINVAL;
 568                                         goto done;
 569                                 }
 570
 571 #ifdef DEBUG
 572                                 if (arg == -10) {
 573                                         usblp_dump(usblp);
 574                                         break;
 575                                 }
 576 #endif
 577
 578                                 usblp_unlink_urbs(usblp);
 579                                 retval = usblp_set_protocol(usblp, arg);
 580                                 if (retval < 0) {
 581                                         usblp_set_protocol(usblp,
 582                                                 usblp->current_protocol);
 583                                 }
 584                                 break;
 585
 586                         case IOCNR_HP_SET_CHANNEL:
 587                                 if (_IOC_DIR(cmd) != _IOC_WRITE ||
 588                                     le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 589                                     usblp->quirks & USBLP_QUIRK_BIDIR) {
 590                                         retval = -EINVAL;
 591                                         goto done;
 592                                 }
 593
 594                                 err = usblp_hp_channel_change_request(usblp,
 595                                         arg, &newChannel);
 596                                 if (err < 0) {
 597                                         dev_err(&usblp->dev->dev,
 598                                                 "usblp%d: error = %d setting "
 599                                                 "HP channel\n",
 600                                                 usblp->minor, err);
 601                                         retval = -EIO;
 602                                         goto done;
 603                                 }
 604
 605                                 dbg("usblp%d requested/got HP channel %ld/%d",
 606                                         usblp->minor, arg, newChannel);
 607                                 break;
 608
 609                         case IOCNR_GET_BUS_ADDRESS:
 610                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 611                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 612                                         retval = -EINVAL;
 613                                         goto done;
 614                                 }
 615
 616                                 twoints[0] = usblp->dev->bus->busnum;
 617                                 twoints[1] = usblp->dev->devnum;
 618                                 if (copy_to_user((void __user *)arg,
 619                                                 (unsigned char *)twoints,
 620                                                 sizeof(twoints))) {
 621                                         retval = -EFAULT;
 622                                         goto done;
 623                                 }
 624
 625                                 dbg("usblp%d is bus=%d, device=%d",
 626                                         usblp->minor, twoints[0], twoints[1]);
 627                                 break;
 628
 629                         case IOCNR_GET_VID_PID:
 630                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 631                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 632                                         retval = -EINVAL;
 633                                         goto done;
 634                                 }
 635
 636                                 twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 637                                 twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 638                                 if (copy_to_user((void __user *)arg,
 639                                                 (unsigned char *)twoints,
 640                                                 sizeof(twoints))) {
 641                                         retval = -EFAULT;
 642                                         goto done;
 643                                 }
 644
 645                                 dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
 646                                         usblp->minor, twoints[0], twoints[1]);
 647                                 break;
 648
 649                         case IOCNR_SOFT_RESET:
 650                                 if (_IOC_DIR(cmd) != _IOC_NONE) {
 651                                         retval = -EINVAL;
 652                                         goto done;
 653                                 }
 654                                 retval = usblp_reset(usblp);
 655                                 break;
 656                         default:
 657                                 retval = -ENOTTY;
 658                 }
 659         else    /* old-style ioctl value */
 660                 switch (cmd) {
 661
 662                         case LPGETSTATUS:
 663                                 if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
 664                                         if (printk_ratelimit())
 665                                                 printk(KERN_ERR "usblp%d:"
 666                                                     "failed reading printer status (%d)\n",
 667                                                     usblp->minor, retval);
 668                                         retval = -EIO;
 669                                         goto done;
 670                                 }
 671                                 status = *usblp->statusbuf;
 672                                 if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
 673                                         retval = -EFAULT;
 674                                 break;
 675
 676                         case LPABORT:
 677                                 if (arg)
 678                                         usblp->flags |= LP_ABORT;
 679                                 else
 680                                         usblp->flags &= ~LP_ABORT;
 681                                 break;
 682
 683                         default:
 684                                 retval = -ENOTTY;
 685                 }
 686
 687 done:
 688         mutex_unlock (&usblp->mut);
 689         return retval;
 690 }
 691
 692 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 693 {
 694         struct urb *urb;
 695         char *writebuf;
 696
 697         if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
 698                 return NULL;
 699         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
 700                 kfree(writebuf);
 701                 return NULL;
 702         }
 703
 704         usb_fill_bulk_urb(urb, usblp->dev,
 705                 usb_sndbulkpipe(usblp->dev,
 706                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 707                 writebuf, transfer_length, usblp_bulk_write, usblp);
 708         urb->transfer_flags |= URB_FREE_BUFFER;
 709
 710         return urb;
 711 }
 712
 713 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 714 {
 715         struct usblp *usblp = file->private_data;
 716         struct urb *writeurb;
 717         int rv;
 718         int transfer_length;
 719         ssize_t writecount = 0;
 720
 721         if (mutex_lock_interruptible(&usblp->wmut)) {
 722                 rv = -EINTR;
 723                 goto raise_biglock;
 724         }
 725         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 726                 goto raise_wait;
 727
 728         while (writecount < count) {
 729                 /*
 730                  * Step 1: Submit next block.
 731                  */
 732                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 733                         transfer_length = USBLP_BUF_SIZE;
 734
 735                 rv = -ENOMEM;
 736                 if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
 737                         goto raise_urb;
 738                 usb_anchor_urb(writeurb, &usblp->urbs);
 739
 740                 if (copy_from_user(writeurb->transfer_buffer,
 741                                    buffer + writecount, transfer_length)) {
 742                         rv = -EFAULT;
 743                         goto raise_badaddr;
 744                 }
 745
 746                 spin_lock_irq(&usblp->lock);
 747                 usblp->wcomplete = 0;
 748                 spin_unlock_irq(&usblp->lock);
 749                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 750                         usblp->wstatus = 0;
 751                         spin_lock_irq(&usblp->lock);
 752                         usblp->no_paper = 0;
 753                         usblp->wcomplete = 1;
 754                         wake_up(&usblp->wwait);
 755                         spin_unlock_irq(&usblp->lock);
 756                         if (rv != -ENOMEM)
 757                                 rv = -EIO;
 758                         goto raise_submit;
 759                 }
 760
 761                 /*
 762                  * Step 2: Wait for transfer to end, collect results.
 763                  */
 764                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 765                 if (rv < 0) {
 766                         if (rv == -EAGAIN) {
 767                                 /* Presume that it's going to complete well. */
 768                                 writecount += transfer_length;
 769                         }
 770                         if (rv == -ENOSPC) {
 771                                 spin_lock_irq(&usblp->lock);
 772                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 773                                 spin_unlock_irq(&usblp->lock);
 774                                 writecount += transfer_length;
 775                         }
 776                         /* Leave URB dangling, to be cleaned on close. */
 777                         goto collect_error;
 778                 }
 779
 780                 if (usblp->wstatus < 0) {
 781                         rv = -EIO;
 782                         goto collect_error;
 783                 }
 784                 /*
 785                  * This is critical: it must be our URB, not other writer's.
 786                  * The wmut exists mainly to cover us here.
 787                  */
 788                 writecount += usblp->wstatus;
 789         }
 790
 791         mutex_unlock(&usblp->wmut);
 792         return writecount;
 793
 794 raise_submit:
 795 raise_badaddr:
 796         usb_unanchor_urb(writeurb);
 797         usb_free_urb(writeurb);
 798 raise_urb:
 799 raise_wait:
 800 collect_error:          /* Out of raise sequence */
 801         mutex_unlock(&usblp->wmut);
 802 raise_biglock:
 803         return writecount ? writecount : rv;
 804 }
 805
 806 /*
 807  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 808  * error, etc. This is the historical behaviour. In all such cases we return
 809  * EIO, and applications loop in order to get the new read going.
 810  */
 811 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 812 {
 813         struct usblp *usblp = file->private_data;
 814         ssize_t count;
 815         ssize_t avail;
 816         int rv;
 817
 818         if (!usblp->bidir)
 819                 return -EINVAL;
 820
 821         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 822         if (rv < 0)
 823                 return rv;
 824
 825         if ((avail = usblp->rstatus) < 0) {
 826                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 827                     usblp->minor, (int)avail);
 828                 usblp_submit_read(usblp);
 829                 count = -EIO;
 830                 goto done;
 831         }
 832
 833         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 834         if (count != 0 &&
 835             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 836                 count = -EFAULT;
 837                 goto done;
 838         }
 839
 840         if ((usblp->readcount += count) == avail) {
 841                 if (usblp_submit_read(usblp) < 0) {
 842                         /* We don't want to leak USB return codes into errno. */
 843                         if (count == 0)
 844                                 count = -EIO;
 845                         goto done;
 846                 }
 847         }
 848
 849 done:
 850         mutex_unlock (&usblp->mut);
 851         return count;
 852 }
 853
 854 /*
 855  * Wait for the write path to come idle.
 856  * This is called under the ->wmut, so the idle path stays idle.
 857  *
 858  * Our write path has a peculiar property: it does not buffer like a tty,
 859  * but waits for the write to succeed. This allows our ->release to bug out
 860  * without waiting for writes to drain. But it obviously does not work
 861  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 862  * select(2) or poll(2) to wait for the buffer to drain before closing.
 863  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 864  */
 865 static int usblp_wwait(struct usblp *usblp, int nonblock)
 866 {
 867         DECLARE_WAITQUEUE(waita, current);
 868         int rc;
 869         int err = 0;
 870
 871         add_wait_queue(&usblp->wwait, &waita);
 872         for (;;) {
 873                 set_current_state(TASK_INTERRUPTIBLE);
 874                 if (mutex_lock_interruptible(&usblp->mut)) {
 875                         rc = -EINTR;
 876                         break;
 877                 }
 878                 rc = usblp_wtest(usblp, nonblock);
 879                 mutex_unlock(&usblp->mut);
 880                 if (rc <= 0)
 881                         break;
 882
 883                 if (usblp->flags & LP_ABORT) {
 884                         if (schedule_timeout(msecs_to_jiffies(5000)) == 0) {
 885                                 err = usblp_check_status(usblp, err);
 886                                 if (err == 1) { /* Paper out */
 887                                         rc = -ENOSPC;
 888                                         break;
 889                                 }
 890                         }
 891                 } else {
 892                         schedule();
 893                 }
 894         }
 895         set_current_state(TASK_RUNNING);
 896         remove_wait_queue(&usblp->wwait, &waita);
 897         return rc;
 898 }
 899
 900 static int usblp_wtest(struct usblp *usblp, int nonblock)
 901 {
 902         unsigned long flags;
 903
 904         if (!usblp->present)
 905                 return -ENODEV;
 906         if (signal_pending(current))
 907                 return -EINTR;
 908         spin_lock_irqsave(&usblp->lock, flags);
 909         if (usblp->wcomplete) {
 910                 spin_unlock_irqrestore(&usblp->lock, flags);
 911                 return 0;
 912         }
 913         spin_unlock_irqrestore(&usblp->lock, flags);
 914         if (usblp->sleeping)
 915                 return -ENODEV;
 916         if (nonblock)
 917                 return -EAGAIN;
 918         return 1;
 919 }
 920
 921 /*
 922  * Wait for read bytes to become available. This probably should have been
 923  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 924  * name for functions which lock and return.
 925  *
 926  * We do not use wait_event_interruptible because it makes locking iffy.
 927  */
 928 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 929 {
 930         DECLARE_WAITQUEUE(waita, current);
 931         int rc;
 932
 933         add_wait_queue(&usblp->rwait, &waita);
 934         for (;;) {
 935                 if (mutex_lock_interruptible(&usblp->mut)) {
 936                         rc = -EINTR;
 937                         break;
 938                 }
 939                 set_current_state(TASK_INTERRUPTIBLE);
 940                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 941                         mutex_unlock(&usblp->mut);
 942                         break;
 943                 }
 944                 if (rc == 0)    /* Keep it locked */
 945                         break;
 946                 mutex_unlock(&usblp->mut);
 947                 schedule();
 948         }
 949         set_current_state(TASK_RUNNING);
 950         remove_wait_queue(&usblp->rwait, &waita);
 951         return rc;
 952 }
 953
 954 static int usblp_rtest(struct usblp *usblp, int nonblock)
 955 {
 956         unsigned long flags;
 957
 958         if (!usblp->present)
 959                 return -ENODEV;
 960         if (signal_pending(current))
 961                 return -EINTR;
 962         spin_lock_irqsave(&usblp->lock, flags);
 963         if (usblp->rcomplete) {
 964                 spin_unlock_irqrestore(&usblp->lock, flags);
 965                 return 0;
 966         }
 967         spin_unlock_irqrestore(&usblp->lock, flags);
 968         if (usblp->sleeping)
 969                 return -ENODEV;
 970         if (nonblock)
 971                 return -EAGAIN;
 972         return 1;
 973 }
 974
 975 /*
 976  * Please check ->bidir and other such things outside for now.
 977  */
 978 static int usblp_submit_read(struct usblp *usblp)
 979 {
 980         struct urb *urb;
 981         unsigned long flags;
 982         int rc;
 983
 984         rc = -ENOMEM;
 985         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
 986                 goto raise_urb;
 987
 988         usb_fill_bulk_urb(urb, usblp->dev,
 989                 usb_rcvbulkpipe(usblp->dev,
 990                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
 991                 usblp->readbuf, USBLP_BUF_SIZE_IN,
 992                 usblp_bulk_read, usblp);
 993         usb_anchor_urb(urb, &usblp->urbs);
 994
 995         spin_lock_irqsave(&usblp->lock, flags);
 996         usblp->readcount = 0; /* XXX Why here? */
 997         usblp->rcomplete = 0;
 998         spin_unlock_irqrestore(&usblp->lock, flags);
 999         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1000                 dbg("error submitting urb (%d)", rc);
1001                 spin_lock_irqsave(&usblp->lock, flags);
1002                 usblp->rstatus = rc;
1003                 usblp->rcomplete = 1;
1004                 spin_unlock_irqrestore(&usblp->lock, flags);
1005                 goto raise_submit;
1006         }
1007
1008         return 0;
1009
1010 raise_submit:
1011         usb_unanchor_urb(urb);
1012         usb_free_urb(urb);
1013 raise_urb:
1014         return rc;
1015 }
1016
1017 /*
1018  * Checks for printers that have quirks, such as requiring unidirectional
1019  * communication but reporting bidirectional; currently some HP printers
1020  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1021  * sent at each open (like some Epsons).
1022  * Returns 1 if found, 0 if not found.
1023  *
1024  * HP recommended that we use the bidirectional interface but
1025  * don't attempt any bulk IN transfers from the IN endpoint.
1026  * Here's some more detail on the problem:
1027  * The problem is not that it isn't bidirectional though. The problem
1028  * is that if you request a device ID, or status information, while
1029  * the buffers are full, the return data will end up in the print data
1030  * buffer. For example if you make sure you never request the device ID
1031  * while you are sending print data, and you don't try to query the
1032  * printer status every couple of milliseconds, you will probably be OK.
1033  */
1034 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
1035 {
1036         int i;
1037
1038         for (i = 0; quirk_printers[i].vendorId; i++) {
1039                 if (vendor == quirk_printers[i].vendorId &&
1040                     product == quirk_printers[i].productId)
1041                         return quirk_printers[i].quirks;
1042         }
1043         return 0;
1044 }
1045
1046 static const struct file_operations usblp_fops = {
1047         .owner =        THIS_MODULE,
1048         .read =         usblp_read,
1049         .write =        usblp_write,
1050         .poll =         usblp_poll,
1051         .unlocked_ioctl =       usblp_ioctl,
1052         .compat_ioctl =         usblp_ioctl,
1053         .open =         usblp_open,
1054         .release =      usblp_release,
1055 };
1056
1057 static struct usb_class_driver usblp_class = {
1058         .name =         "lp%d",
1059         .fops =         &usblp_fops,
1060         .minor_base =   USBLP_MINOR_BASE,
1061 };
1062
1063 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1064 {
1065         struct usb_interface *intf = to_usb_interface(dev);
1066         struct usblp *usblp = usb_get_intfdata (intf);
1067
1068         if (usblp->device_id_string[0] == 0 &&
1069             usblp->device_id_string[1] == 0)
1070                 return 0;
1071
1072         return sprintf(buf, "%s", usblp->device_id_string+2);
1073 }
1074
1075 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1076
1077 static int usblp_probe(struct usb_interface *intf,
1078                        const struct usb_device_id *id)
1079 {
1080         struct usb_device *dev = interface_to_usbdev (intf);
1081         struct usblp *usblp;
1082         int protocol;
1083         int retval;
1084
1085         /* Malloc and start initializing usblp structure so we can use it
1086          * directly. */
1087         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1088         if (!usblp) {
1089                 retval = -ENOMEM;
1090                 goto abort_ret;
1091         }
1092         usblp->dev = dev;
1093         mutex_init(&usblp->wmut);
1094         mutex_init (&usblp->mut);
1095         spin_lock_init(&usblp->lock);
1096         init_waitqueue_head(&usblp->rwait);
1097         init_waitqueue_head(&usblp->wwait);
1098         init_usb_anchor(&usblp->urbs);
1099         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1100         usblp->intf = intf;
1101
1102         /* Malloc device ID string buffer to the largest expected length,
1103          * since we can re-query it on an ioctl and a dynamic string
1104          * could change in length. */
1105         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1106                 retval = -ENOMEM;
1107                 goto abort;
1108         }
1109
1110         /*
1111          * Allocate read buffer. We somewhat wastefully
1112          * malloc both regardless of bidirectionality, because the
1113          * alternate setting can be changed later via an ioctl.
1114          */
1115         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1116                 retval = -ENOMEM;
1117                 goto abort;
1118         }
1119
1120         /* Allocate buffer for printer status */
1121         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1122         if (!usblp->statusbuf) {
1123                 retval = -ENOMEM;
1124                 goto abort;
1125         }
1126
1127         /* Lookup quirks for this printer. */
1128         usblp->quirks = usblp_quirks(
1129                 le16_to_cpu(dev->descriptor.idVendor),
1130                 le16_to_cpu(dev->descriptor.idProduct));
1131
1132         /* Analyze and pick initial alternate settings and endpoints. */
1133         protocol = usblp_select_alts(usblp);
1134         if (protocol < 0) {
1135                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
1136                         le16_to_cpu(dev->descriptor.idVendor),
1137                         le16_to_cpu(dev->descriptor.idProduct));
1138                 retval = -ENODEV;
1139                 goto abort;
1140         }
1141
1142         /* Setup the selected alternate setting and endpoints. */
1143         if (usblp_set_protocol(usblp, protocol) < 0) {
1144                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1145                 goto abort;
1146         }
1147
1148         /* Retrieve and store the device ID string. */
1149         usblp_cache_device_id_string(usblp);
1150         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1151         if (retval)
1152                 goto abort_intfdata;
1153
1154 #ifdef DEBUG
1155         usblp_check_status(usblp, 0);
1156 #endif
1157
1158         usb_set_intfdata (intf, usblp);
1159
1160         usblp->present = 1;
1161
1162         retval = usb_register_dev(intf, &usblp_class);
1163         if (retval) {
1164                 printk(KERN_ERR "usblp: Not able to get a minor"
1165                     " (base %u, slice default): %d\n",
1166                     USBLP_MINOR_BASE, retval);
1167                 goto abort_intfdata;
1168         }
1169         usblp->minor = intf->minor;
1170         printk(KERN_INFO "usblp%d: USB %sdirectional printer dev %d "
1171                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1172                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1173                 usblp->ifnum,
1174                 usblp->protocol[usblp->current_protocol].alt_setting,
1175                 usblp->current_protocol,
1176                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1177                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1178
1179         return 0;
1180
1181 abort_intfdata:
1182         usb_set_intfdata (intf, NULL);
1183         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1184 abort:
1185         kfree(usblp->readbuf);
1186         kfree(usblp->statusbuf);
1187         kfree(usblp->device_id_string);
1188         kfree(usblp);
1189 abort_ret:
1190         return retval;
1191 }
1192
1193 /*
1194  * We are a "new" style driver with usb_device_id table,
1195  * but our requirements are too intricate for simple match to handle.
1196  *
1197  * The "proto_bias" option may be used to specify the preferred protocol
1198  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1199  * supports the preferred protocol, then we bind to it.
1200  *
1201  * The best interface for us is 7/1/2, because it is compatible
1202  * with a stream of characters. If we find it, we bind to it.
1203  *
1204  * Note that the people from hpoj.sourceforge.net need to be able to
1205  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1206  *
1207  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1208  * stream-compatible, because this matches the behaviour of the old code.
1209  *
1210  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1211  */
1212 static int usblp_select_alts(struct usblp *usblp)
1213 {
1214         struct usb_interface *if_alt;
1215         struct usb_host_interface *ifd;
1216         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1217         int p, i, e;
1218
1219         if_alt = usblp->intf;
1220
1221         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1222                 usblp->protocol[p].alt_setting = -1;
1223
1224         /* Find out what we have. */
1225         for (i = 0; i < if_alt->num_altsetting; i++) {
1226                 ifd = &if_alt->altsetting[i];
1227
1228                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1229                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1230                                 continue;
1231
1232                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1233                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1234                         continue;
1235
1236                 /* Look for bulk OUT and IN endpoints. */
1237                 epwrite = epread = NULL;
1238                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1239                         epd = &ifd->endpoint[e].desc;
1240
1241                         if (usb_endpoint_is_bulk_out(epd))
1242                                 if (!epwrite)
1243                                         epwrite = epd;
1244
1245                         if (usb_endpoint_is_bulk_in(epd))
1246                                 if (!epread)
1247                                         epread = epd;
1248                 }
1249
1250                 /* Ignore buggy hardware without the right endpoints. */
1251                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1252                         continue;
1253
1254                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1255                  * and buggy bidirectional printers. */
1256                 if (ifd->desc.bInterfaceProtocol == 1) {
1257                         epread = NULL;
1258                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1259                         printk(KERN_INFO "usblp%d: Disabling reads from "
1260                             "problematic bidirectional printer\n",
1261                             usblp->minor);
1262                         epread = NULL;
1263                 }
1264
1265                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1266                                 ifd->desc.bAlternateSetting;
1267                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1268                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1269         }
1270
1271         /* If our requested protocol is supported, then use it. */
1272         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1273             proto_bias <= USBLP_LAST_PROTOCOL &&
1274             usblp->protocol[proto_bias].alt_setting != -1)
1275                 return proto_bias;
1276
1277         /* Ordering is important here. */
1278         if (usblp->protocol[2].alt_setting != -1)
1279                 return 2;
1280         if (usblp->protocol[1].alt_setting != -1)
1281                 return 1;
1282         if (usblp->protocol[3].alt_setting != -1)
1283                 return 3;
1284
1285         /* If nothing is available, then don't bind to this device. */
1286         return -1;
1287 }
1288
1289 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1290 {
1291         int r, alts;
1292
1293         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1294                 return -EINVAL;
1295
1296         alts = usblp->protocol[protocol].alt_setting;
1297         if (alts < 0)
1298                 return -EINVAL;
1299         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1300         if (r < 0) {
1301                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1302                         alts, usblp->ifnum);
1303                 return r;
1304         }
1305
1306         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1307         usblp->current_protocol = protocol;
1308         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1309         return 0;
1310 }
1311
1312 /* Retrieves and caches device ID string.
1313  * Returns length, including length bytes but not null terminator.
1314  * On error, returns a negative errno value. */
1315 static int usblp_cache_device_id_string(struct usblp *usblp)
1316 {
1317         int err, length;
1318
1319         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1320         if (err < 0) {
1321                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1322                         usblp->minor, err);
1323                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1324                 return -EIO;
1325         }
1326
1327         /* First two bytes are length in big-endian.
1328          * They count themselves, and we copy them into
1329          * the user's buffer. */
1330         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1331         if (length < 2)
1332                 length = 2;
1333         else if (length >= USBLP_DEVICE_ID_SIZE)
1334                 length = USBLP_DEVICE_ID_SIZE - 1;
1335         usblp->device_id_string[length] = '\0';
1336
1337         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1338                 usblp->minor, length, &usblp->device_id_string[2]);
1339
1340         return length;
1341 }
1342
1343 static void usblp_disconnect(struct usb_interface *intf)
1344 {
1345         struct usblp *usblp = usb_get_intfdata (intf);
1346
1347         usb_deregister_dev(intf, &usblp_class);
1348
1349         if (!usblp || !usblp->dev) {
1350                 dev_err(&intf->dev, "bogus disconnect\n");
1351                 BUG ();
1352         }
1353
1354         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1355
1356         mutex_lock (&usblp_mutex);
1357         mutex_lock (&usblp->mut);
1358         usblp->present = 0;
1359         wake_up(&usblp->wwait);
1360         wake_up(&usblp->rwait);
1361         usb_set_intfdata (intf, NULL);
1362
1363         usblp_unlink_urbs(usblp);
1364         mutex_unlock (&usblp->mut);
1365
1366         if (!usblp->used)
1367                 usblp_cleanup (usblp);
1368         mutex_unlock (&usblp_mutex);
1369 }
1370
1371 static int usblp_suspend (struct usb_interface *intf, pm_message_t message)
1372 {
1373         struct usblp *usblp = usb_get_intfdata (intf);
1374
1375         /* we take no more IO */
1376         usblp->sleeping = 1;
1377         usblp_unlink_urbs(usblp);
1378 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1379         /* not strictly necessary, but just in case */
1380         wake_up(&usblp->wwait);
1381         wake_up(&usblp->rwait);
1382 #endif
1383
1384         return 0;
1385 }
1386
1387 static int usblp_resume (struct usb_interface *intf)
1388 {
1389         struct usblp *usblp = usb_get_intfdata (intf);
1390         int r;
1391
1392         usblp->sleeping = 0;
1393         r = handle_bidir (usblp);
1394
1395         return r;
1396 }
1397
1398 static struct usb_device_id usblp_ids [] = {
1399         { USB_DEVICE_INFO(7, 1, 1) },
1400         { USB_DEVICE_INFO(7, 1, 2) },
1401         { USB_DEVICE_INFO(7, 1, 3) },
1402         { USB_INTERFACE_INFO(7, 1, 1) },
1403         { USB_INTERFACE_INFO(7, 1, 2) },
1404         { USB_INTERFACE_INFO(7, 1, 3) },
1405         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1406         { }                                             /* Terminating entry */
1407 };
1408
1409 MODULE_DEVICE_TABLE (usb, usblp_ids);
1410
1411 static struct usb_driver usblp_driver = {
1412         .name =         "usblp",
1413         .probe =        usblp_probe,
1414         .disconnect =   usblp_disconnect,
1415         .suspend =      usblp_suspend,
1416         .resume =       usblp_resume,
1417         .id_table =     usblp_ids,
1418         .supports_autosuspend = 1,
1419 };
1420
1421 static int __init usblp_init(void)
1422 {
1423         return usb_register(&usblp_driver);
1424 }
1425
1426 static void __exit usblp_exit(void)
1427 {
1428         usb_deregister(&usblp_driver);
1429 }
1430
1431 module_init(usblp_init);
1432 module_exit(usblp_exit);
1433
1434 MODULE_AUTHOR( DRIVER_AUTHOR );
1435 MODULE_DESCRIPTION( DRIVER_DESC );
1436 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1437 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1438 MODULE_LICENSE("GPL");