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