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 #include <linux/smp_lock.h>
  60 #undef DEBUG
  61 #include <linux/usb.h>
  62
  63 /*
  64  * Version Information
  65  */
  66 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  67 #define DRIVER_DESC "USB Printer Device Class driver"
  68
  69 #define USBLP_BUF_SIZE          8192
  70 #define USBLP_BUF_SIZE_IN       1024
  71 #define USBLP_DEVICE_ID_SIZE    1024
  72
  73 /* ioctls: */
  74 #define IOCNR_GET_DEVICE_ID             1
  75 #define IOCNR_GET_PROTOCOLS             2
  76 #define IOCNR_SET_PROTOCOL              3
  77 #define IOCNR_HP_SET_CHANNEL            4
  78 #define IOCNR_GET_BUS_ADDRESS           5
  79 #define IOCNR_GET_VID_PID               6
  80 #define IOCNR_SOFT_RESET                7
  81 /* Get device_id string: */
  82 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  83 /* The following ioctls were added for http://hpoj.sourceforge.net: */
  84 /* Get two-int array:
  85  * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
  86  * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
  87 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  88 /* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
  89 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  90 /* Set channel number (HP Vendor-specific command): */
  91 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
  92 /* Get two-int array: [0]=bus number, [1]=device address: */
  93 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
  94 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
  95 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
  96 /* Perform class specific soft reset */
  97 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
  98
  99 /*
 100  * A DEVICE_ID string may include the printer's serial number.
 101  * It should end with a semi-colon (';').
 102  * An example from an HP 970C DeskJet printer is (this is one long string,
 103  * with the serial number changed):
 104 MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
 105  */
 106
 107 /*
 108  * USB Printer Requests
 109  */
 110
 111 #define USBLP_REQ_GET_ID                        0x00
 112 #define USBLP_REQ_GET_STATUS                    0x01
 113 #define USBLP_REQ_RESET                         0x02
 114 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
 115
 116 #define USBLP_MINORS            16
 117 #define USBLP_MINOR_BASE        0
 118
 119 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
 120
 121 #define USBLP_FIRST_PROTOCOL    1
 122 #define USBLP_LAST_PROTOCOL     3
 123 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
 124
 125 /*
 126  * some arbitrary status buffer size;
 127  * need a status buffer that is allocated via kmalloc(), not on stack
 128  */
 129 #define STATUS_BUF_SIZE         8
 130
 131 /*
 132  * Locks down the locking order:
 133  * ->wmut locks wstatus.
 134  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 135  * [rw]status. We only touch status when we know the side idle.
 136  * ->lock locks what interrupt accesses.
 137  */
 138 struct usblp {
 139         struct usb_device       *dev;                   /* USB device */
 140         struct mutex            wmut;
 141         struct mutex            mut;
 142         spinlock_t              lock;           /* locks rcomplete, wcomplete */
 143         char                    *readbuf;               /* read transfer_buffer */
 144         char                    *statusbuf;             /* status transfer_buffer */
 145         struct usb_anchor       urbs;
 146         wait_queue_head_t       rwait, wwait;
 147         int                     readcount;              /* Counter for reads */
 148         int                     ifnum;                  /* Interface number */
 149         struct usb_interface    *intf;                  /* The interface */
 150         /* Alternate-setting numbers and endpoints for each protocol
 151          * (7/1/{index=1,2,3}) that the device supports: */
 152         struct {
 153                 int                             alt_setting;
 154                 struct usb_endpoint_descriptor  *epwrite;
 155                 struct usb_endpoint_descriptor  *epread;
 156         }                       protocol[USBLP_MAX_PROTOCOLS];
 157         int                     current_protocol;
 158         int                     minor;                  /* minor number of device */
 159         int                     wcomplete, rcomplete;
 160         int                     wstatus;        /* bytes written or error */
 161         int                     rstatus;        /* bytes ready or error */
 162         unsigned int            quirks;                 /* quirks flags */
 163         unsigned int            flags;                  /* mode flags */
 164         unsigned char           used;                   /* True if open */
 165         unsigned char           present;                /* True if not disconnected */
 166         unsigned char           bidir;                  /* interface is bidirectional */
 167         unsigned char           no_paper;               /* Paper Out happened */
 168         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 169                                                         /* first 2 bytes are (big-endian) length */
 170 };
 171
 172 #ifdef DEBUG
 173 static void usblp_dump(struct usblp *usblp) {
 174         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("device_id_string=\"%s\"",
 195                 usblp->device_id_string ?
 196                         usblp->device_id_string + 2 :
 197                         (unsigned char *)"(null)");
 198 }
 199 #endif
 200
 201 /* Quirks: various printer quirks are handled by this table & its flags. */
 202
 203 struct quirk_printer_struct {
 204         __u16 vendorId;
 205         __u16 productId;
 206         unsigned int quirks;
 207 };
 208
 209 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 210 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 211 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
 212
 213 static const struct quirk_printer_struct quirk_printers[] = {
 214         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 215         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 216         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 217         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 218         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 219         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 220         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 221         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 222         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 223         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 224         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 225         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 226         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 227         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
 228         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 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) {
 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         lock_kernel();
 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         unlock_kernel();
 440         return retval;
 441 }
 442
 443 static void usblp_cleanup (struct usblp *usblp)
 444 {
 445         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 446
 447         kfree(usblp->readbuf);
 448         kfree (usblp->device_id_string);
 449         kfree (usblp->statusbuf);
 450         kfree (usblp);
 451 }
 452
 453 static void usblp_unlink_urbs(struct usblp *usblp)
 454 {
 455         usb_kill_anchored_urbs(&usblp->urbs);
 456 }
 457
 458 static int usblp_release(struct inode *inode, struct file *file)
 459 {
 460         struct usblp *usblp = file->private_data;
 461
 462         usblp->flags &= ~LP_ABORT;
 463
 464         mutex_lock (&usblp_mutex);
 465         usblp->used = 0;
 466         if (usblp->present) {
 467                 usblp_unlink_urbs(usblp);
 468                 usb_autopm_put_interface(usblp->intf);
 469         } else          /* finish cleanup from disconnect */
 470                 usblp_cleanup (usblp);
 471         mutex_unlock (&usblp_mutex);
 472         return 0;
 473 }
 474
 475 /* No kernel lock - fine */
 476 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
 477 {
 478         int ret;
 479         unsigned long flags;
 480
 481         struct usblp *usblp = file->private_data;
 482         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 483         poll_wait(file, &usblp->rwait, wait);
 484         poll_wait(file, &usblp->wwait, wait);
 485         spin_lock_irqsave(&usblp->lock, flags);
 486         ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
 487            ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
 488         spin_unlock_irqrestore(&usblp->lock, flags);
 489         return ret;
 490 }
 491
 492 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 493 {
 494         struct usblp *usblp = file->private_data;
 495         int length, err, i;
 496         unsigned char newChannel;
 497         int status;
 498         int twoints[2];
 499         int retval = 0;
 500
 501         mutex_lock (&usblp->mut);
 502         if (!usblp->present) {
 503                 retval = -ENODEV;
 504                 goto done;
 505         }
 506
 507         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
 508                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
 509
 510         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 511
 512                 switch (_IOC_NR(cmd)) {
 513
 514                         case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 515                                 if (_IOC_DIR(cmd) != _IOC_READ) {
 516                                         retval = -EINVAL;
 517                                         goto done;
 518                                 }
 519
 520                                 length = usblp_cache_device_id_string(usblp);
 521                                 if (length < 0) {
 522                                         retval = length;
 523                                         goto done;
 524                                 }
 525                                 if (length > _IOC_SIZE(cmd))
 526                                         length = _IOC_SIZE(cmd); /* truncate */
 527
 528                                 if (copy_to_user((void __user *) arg,
 529                                                 usblp->device_id_string,
 530                                                 (unsigned long) length)) {
 531                                         retval = -EFAULT;
 532                                         goto done;
 533                                 }
 534
 535                                 break;
 536
 537                         case IOCNR_GET_PROTOCOLS:
 538                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 539                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 540                                         retval = -EINVAL;
 541                                         goto done;
 542                                 }
 543
 544                                 twoints[0] = usblp->current_protocol;
 545                                 twoints[1] = 0;
 546                                 for (i = USBLP_FIRST_PROTOCOL;
 547                                      i <= USBLP_LAST_PROTOCOL; i++) {
 548                                         if (usblp->protocol[i].alt_setting >= 0)
 549                                                 twoints[1] |= (1<<i);
 550                                 }
 551
 552                                 if (copy_to_user((void __user *)arg,
 553                                                 (unsigned char *)twoints,
 554                                                 sizeof(twoints))) {
 555                                         retval = -EFAULT;
 556                                         goto done;
 557                                 }
 558
 559                                 break;
 560
 561                         case IOCNR_SET_PROTOCOL:
 562                                 if (_IOC_DIR(cmd) != _IOC_WRITE) {
 563                                         retval = -EINVAL;
 564                                         goto done;
 565                                 }
 566
 567 #ifdef DEBUG
 568                                 if (arg == -10) {
 569                                         usblp_dump(usblp);
 570                                         break;
 571                                 }
 572 #endif
 573
 574                                 usblp_unlink_urbs(usblp);
 575                                 retval = usblp_set_protocol(usblp, arg);
 576                                 if (retval < 0) {
 577                                         usblp_set_protocol(usblp,
 578                                                 usblp->current_protocol);
 579                                 }
 580                                 break;
 581
 582                         case IOCNR_HP_SET_CHANNEL:
 583                                 if (_IOC_DIR(cmd) != _IOC_WRITE ||
 584                                     le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 585                                     usblp->quirks & USBLP_QUIRK_BIDIR) {
 586                                         retval = -EINVAL;
 587                                         goto done;
 588                                 }
 589
 590                                 err = usblp_hp_channel_change_request(usblp,
 591                                         arg, &newChannel);
 592                                 if (err < 0) {
 593                                         dev_err(&usblp->dev->dev,
 594                                                 "usblp%d: error = %d setting "
 595                                                 "HP channel\n",
 596                                                 usblp->minor, err);
 597                                         retval = -EIO;
 598                                         goto done;
 599                                 }
 600
 601                                 dbg("usblp%d requested/got HP channel %ld/%d",
 602                                         usblp->minor, arg, newChannel);
 603                                 break;
 604
 605                         case IOCNR_GET_BUS_ADDRESS:
 606                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 607                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 608                                         retval = -EINVAL;
 609                                         goto done;
 610                                 }
 611
 612                                 twoints[0] = usblp->dev->bus->busnum;
 613                                 twoints[1] = usblp->dev->devnum;
 614                                 if (copy_to_user((void __user *)arg,
 615                                                 (unsigned char *)twoints,
 616                                                 sizeof(twoints))) {
 617                                         retval = -EFAULT;
 618                                         goto done;
 619                                 }
 620
 621                                 dbg("usblp%d is bus=%d, device=%d",
 622                                         usblp->minor, twoints[0], twoints[1]);
 623                                 break;
 624
 625                         case IOCNR_GET_VID_PID:
 626                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 627                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 628                                         retval = -EINVAL;
 629                                         goto done;
 630                                 }
 631
 632                                 twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 633                                 twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 634                                 if (copy_to_user((void __user *)arg,
 635                                                 (unsigned char *)twoints,
 636                                                 sizeof(twoints))) {
 637                                         retval = -EFAULT;
 638                                         goto done;
 639                                 }
 640
 641                                 dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
 642                                         usblp->minor, twoints[0], twoints[1]);
 643                                 break;
 644
 645                         case IOCNR_SOFT_RESET:
 646                                 if (_IOC_DIR(cmd) != _IOC_NONE) {
 647                                         retval = -EINVAL;
 648                                         goto done;
 649                                 }
 650                                 retval = usblp_reset(usblp);
 651                                 break;
 652                         default:
 653                                 retval = -ENOTTY;
 654                 }
 655         else    /* old-style ioctl value */
 656                 switch (cmd) {
 657
 658                         case LPGETSTATUS:
 659                                 if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
 660                                         if (printk_ratelimit())
 661                                                 printk(KERN_ERR "usblp%d:"
 662                                                     "failed reading printer status (%d)\n",
 663                                                     usblp->minor, retval);
 664                                         retval = -EIO;
 665                                         goto done;
 666                                 }
 667                                 status = *usblp->statusbuf;
 668                                 if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
 669                                         retval = -EFAULT;
 670                                 break;
 671
 672                         case LPABORT:
 673                                 if (arg)
 674                                         usblp->flags |= LP_ABORT;
 675                                 else
 676                                         usblp->flags &= ~LP_ABORT;
 677                                 break;
 678
 679                         default:
 680                                 retval = -ENOTTY;
 681                 }
 682
 683 done:
 684         mutex_unlock (&usblp->mut);
 685         return retval;
 686 }
 687
 688 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 689 {
 690         struct urb *urb;
 691         char *writebuf;
 692
 693         if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
 694                 return NULL;
 695         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
 696                 kfree(writebuf);
 697                 return NULL;
 698         }
 699
 700         usb_fill_bulk_urb(urb, usblp->dev,
 701                 usb_sndbulkpipe(usblp->dev,
 702                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 703                 writebuf, transfer_length, usblp_bulk_write, usblp);
 704         urb->transfer_flags |= URB_FREE_BUFFER;
 705
 706         return urb;
 707 }
 708
 709 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 710 {
 711         struct usblp *usblp = file->private_data;
 712         struct urb *writeurb;
 713         int rv;
 714         int transfer_length;
 715         ssize_t writecount = 0;
 716
 717         if (mutex_lock_interruptible(&usblp->wmut)) {
 718                 rv = -EINTR;
 719                 goto raise_biglock;
 720         }
 721         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 722                 goto raise_wait;
 723
 724         while (writecount < count) {
 725                 /*
 726                  * Step 1: Submit next block.
 727                  */
 728                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 729                         transfer_length = USBLP_BUF_SIZE;
 730
 731                 rv = -ENOMEM;
 732                 if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
 733                         goto raise_urb;
 734                 usb_anchor_urb(writeurb, &usblp->urbs);
 735
 736                 if (copy_from_user(writeurb->transfer_buffer,
 737                                    buffer + writecount, transfer_length)) {
 738                         rv = -EFAULT;
 739                         goto raise_badaddr;
 740                 }
 741
 742                 spin_lock_irq(&usblp->lock);
 743                 usblp->wcomplete = 0;
 744                 spin_unlock_irq(&usblp->lock);
 745                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 746                         usblp->wstatus = 0;
 747                         spin_lock_irq(&usblp->lock);
 748                         usblp->no_paper = 0;
 749                         usblp->wcomplete = 1;
 750                         wake_up(&usblp->wwait);
 751                         spin_unlock_irq(&usblp->lock);
 752                         if (rv != -ENOMEM)
 753                                 rv = -EIO;
 754                         goto raise_submit;
 755                 }
 756
 757                 /*
 758                  * Step 2: Wait for transfer to end, collect results.
 759                  */
 760                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 761                 if (rv < 0) {
 762                         if (rv == -EAGAIN) {
 763                                 /* Presume that it's going to complete well. */
 764                                 writecount += transfer_length;
 765                         }
 766                         if (rv == -ENOSPC) {
 767                                 spin_lock_irq(&usblp->lock);
 768                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 769                                 spin_unlock_irq(&usblp->lock);
 770                                 writecount += transfer_length;
 771                         }
 772                         /* Leave URB dangling, to be cleaned on close. */
 773                         goto collect_error;
 774                 }
 775
 776                 if (usblp->wstatus < 0) {
 777                         rv = -EIO;
 778                         goto collect_error;
 779                 }
 780                 /*
 781                  * This is critical: it must be our URB, not other writer's.
 782                  * The wmut exists mainly to cover us here.
 783                  */
 784                 writecount += usblp->wstatus;
 785         }
 786
 787         mutex_unlock(&usblp->wmut);
 788         return writecount;
 789
 790 raise_submit:
 791 raise_badaddr:
 792         usb_unanchor_urb(writeurb);
 793         usb_free_urb(writeurb);
 794 raise_urb:
 795 raise_wait:
 796 collect_error:          /* Out of raise sequence */
 797         mutex_unlock(&usblp->wmut);
 798 raise_biglock:
 799         return writecount ? writecount : rv;
 800 }
 801
 802 /*
 803  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 804  * error, etc. This is the historical behaviour. In all such cases we return
 805  * EIO, and applications loop in order to get the new read going.
 806  */
 807 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 808 {
 809         struct usblp *usblp = file->private_data;
 810         ssize_t count;
 811         ssize_t avail;
 812         int rv;
 813
 814         if (!usblp->bidir)
 815                 return -EINVAL;
 816
 817         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 818         if (rv < 0)
 819                 return rv;
 820
 821         if ((avail = usblp->rstatus) < 0) {
 822                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 823                     usblp->minor, (int)avail);
 824                 usblp_submit_read(usblp);
 825                 count = -EIO;
 826                 goto done;
 827         }
 828
 829         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 830         if (count != 0 &&
 831             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 832                 count = -EFAULT;
 833                 goto done;
 834         }
 835
 836         if ((usblp->readcount += count) == avail) {
 837                 if (usblp_submit_read(usblp) < 0) {
 838                         /* We don't want to leak USB return codes into errno. */
 839                         if (count == 0)
 840                                 count = -EIO;
 841                         goto done;
 842                 }
 843         }
 844
 845 done:
 846         mutex_unlock (&usblp->mut);
 847         return count;
 848 }
 849
 850 /*
 851  * Wait for the write path to come idle.
 852  * This is called under the ->wmut, so the idle path stays idle.
 853  *
 854  * Our write path has a peculiar property: it does not buffer like a tty,
 855  * but waits for the write to succeed. This allows our ->release to bug out
 856  * without waiting for writes to drain. But it obviously does not work
 857  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 858  * select(2) or poll(2) to wait for the buffer to drain before closing.
 859  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 860  */
 861 static int usblp_wwait(struct usblp *usblp, int nonblock)
 862 {
 863         DECLARE_WAITQUEUE(waita, current);
 864         int rc;
 865         int err = 0;
 866
 867         add_wait_queue(&usblp->wwait, &waita);
 868         for (;;) {
 869                 set_current_state(TASK_INTERRUPTIBLE);
 870                 if (mutex_lock_interruptible(&usblp->mut)) {
 871                         rc = -EINTR;
 872                         break;
 873                 }
 874                 rc = usblp_wtest(usblp, nonblock);
 875                 mutex_unlock(&usblp->mut);
 876                 if (rc <= 0)
 877                         break;
 878
 879                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 880                         if (usblp->flags & LP_ABORT) {
 881                                 err = usblp_check_status(usblp, err);
 882                                 if (err == 1) { /* Paper out */
 883                                         rc = -ENOSPC;
 884                                         break;
 885                                 }
 886                         } else {
 887                                 /* Prod the printer, Gentoo#251237. */
 888                                 mutex_lock(&usblp->mut);
 889                                 usblp_read_status(usblp, usblp->statusbuf);
 890                                 mutex_unlock(&usblp->mut);
 891                         }
 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 (nonblock)
 914                 return -EAGAIN;
 915         return 1;
 916 }
 917
 918 /*
 919  * Wait for read bytes to become available. This probably should have been
 920  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 921  * name for functions which lock and return.
 922  *
 923  * We do not use wait_event_interruptible because it makes locking iffy.
 924  */
 925 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 926 {
 927         DECLARE_WAITQUEUE(waita, current);
 928         int rc;
 929
 930         add_wait_queue(&usblp->rwait, &waita);
 931         for (;;) {
 932                 if (mutex_lock_interruptible(&usblp->mut)) {
 933                         rc = -EINTR;
 934                         break;
 935                 }
 936                 set_current_state(TASK_INTERRUPTIBLE);
 937                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 938                         mutex_unlock(&usblp->mut);
 939                         break;
 940                 }
 941                 if (rc == 0)    /* Keep it locked */
 942                         break;
 943                 mutex_unlock(&usblp->mut);
 944                 schedule();
 945         }
 946         set_current_state(TASK_RUNNING);
 947         remove_wait_queue(&usblp->rwait, &waita);
 948         return rc;
 949 }
 950
 951 static int usblp_rtest(struct usblp *usblp, int nonblock)
 952 {
 953         unsigned long flags;
 954
 955         if (!usblp->present)
 956                 return -ENODEV;
 957         if (signal_pending(current))
 958                 return -EINTR;
 959         spin_lock_irqsave(&usblp->lock, flags);
 960         if (usblp->rcomplete) {
 961                 spin_unlock_irqrestore(&usblp->lock, flags);
 962                 return 0;
 963         }
 964         spin_unlock_irqrestore(&usblp->lock, flags);
 965         if (nonblock)
 966                 return -EAGAIN;
 967         return 1;
 968 }
 969
 970 /*
 971  * Please check ->bidir and other such things outside for now.
 972  */
 973 static int usblp_submit_read(struct usblp *usblp)
 974 {
 975         struct urb *urb;
 976         unsigned long flags;
 977         int rc;
 978
 979         rc = -ENOMEM;
 980         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
 981                 goto raise_urb;
 982
 983         usb_fill_bulk_urb(urb, usblp->dev,
 984                 usb_rcvbulkpipe(usblp->dev,
 985                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
 986                 usblp->readbuf, USBLP_BUF_SIZE_IN,
 987                 usblp_bulk_read, usblp);
 988         usb_anchor_urb(urb, &usblp->urbs);
 989
 990         spin_lock_irqsave(&usblp->lock, flags);
 991         usblp->readcount = 0; /* XXX Why here? */
 992         usblp->rcomplete = 0;
 993         spin_unlock_irqrestore(&usblp->lock, flags);
 994         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
 995                 dbg("error submitting urb (%d)", rc);
 996                 spin_lock_irqsave(&usblp->lock, flags);
 997                 usblp->rstatus = rc;
 998                 usblp->rcomplete = 1;
 999                 spin_unlock_irqrestore(&usblp->lock, flags);
1000                 goto raise_submit;
1001         }
1002
1003         return 0;
1004
1005 raise_submit:
1006         usb_unanchor_urb(urb);
1007         usb_free_urb(urb);
1008 raise_urb:
1009         return rc;
1010 }
1011
1012 /*
1013  * Checks for printers that have quirks, such as requiring unidirectional
1014  * communication but reporting bidirectional; currently some HP printers
1015  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1016  * sent at each open (like some Epsons).
1017  * Returns 1 if found, 0 if not found.
1018  *
1019  * HP recommended that we use the bidirectional interface but
1020  * don't attempt any bulk IN transfers from the IN endpoint.
1021  * Here's some more detail on the problem:
1022  * The problem is not that it isn't bidirectional though. The problem
1023  * is that if you request a device ID, or status information, while
1024  * the buffers are full, the return data will end up in the print data
1025  * buffer. For example if you make sure you never request the device ID
1026  * while you are sending print data, and you don't try to query the
1027  * printer status every couple of milliseconds, you will probably be OK.
1028  */
1029 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
1030 {
1031         int i;
1032
1033         for (i = 0; quirk_printers[i].vendorId; i++) {
1034                 if (vendor == quirk_printers[i].vendorId &&
1035                     product == quirk_printers[i].productId)
1036                         return quirk_printers[i].quirks;
1037         }
1038         return 0;
1039 }
1040
1041 static const struct file_operations usblp_fops = {
1042         .owner =        THIS_MODULE,
1043         .read =         usblp_read,
1044         .write =        usblp_write,
1045         .poll =         usblp_poll,
1046         .unlocked_ioctl =       usblp_ioctl,
1047         .compat_ioctl =         usblp_ioctl,
1048         .open =         usblp_open,
1049         .release =      usblp_release,
1050 };
1051
1052 static char *usblp_devnode(struct device *dev, mode_t *mode)
1053 {
1054         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1055 }
1056
1057 static struct usb_class_driver usblp_class = {
1058         .name =         "lp%d",
1059         .devnode =      usblp_devnode,
1060         .fops =         &usblp_fops,
1061         .minor_base =   USBLP_MINOR_BASE,
1062 };
1063
1064 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1065 {
1066         struct usb_interface *intf = to_usb_interface(dev);
1067         struct usblp *usblp = usb_get_intfdata (intf);
1068
1069         if (usblp->device_id_string[0] == 0 &&
1070             usblp->device_id_string[1] == 0)
1071                 return 0;
1072
1073         return sprintf(buf, "%s", usblp->device_id_string+2);
1074 }
1075
1076 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1077
1078 static int usblp_probe(struct usb_interface *intf,
1079                        const struct usb_device_id *id)
1080 {
1081         struct usb_device *dev = interface_to_usbdev (intf);
1082         struct usblp *usblp;
1083         int protocol;
1084         int retval;
1085
1086         /* Malloc and start initializing usblp structure so we can use it
1087          * directly. */
1088         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1089         if (!usblp) {
1090                 retval = -ENOMEM;
1091                 goto abort_ret;
1092         }
1093         usblp->dev = dev;
1094         mutex_init(&usblp->wmut);
1095         mutex_init (&usblp->mut);
1096         spin_lock_init(&usblp->lock);
1097         init_waitqueue_head(&usblp->rwait);
1098         init_waitqueue_head(&usblp->wwait);
1099         init_usb_anchor(&usblp->urbs);
1100         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1101         usblp->intf = intf;
1102
1103         /* Malloc device ID string buffer to the largest expected length,
1104          * since we can re-query it on an ioctl and a dynamic string
1105          * could change in length. */
1106         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1107                 retval = -ENOMEM;
1108                 goto abort;
1109         }
1110
1111         /*
1112          * Allocate read buffer. We somewhat wastefully
1113          * malloc both regardless of bidirectionality, because the
1114          * alternate setting can be changed later via an ioctl.
1115          */
1116         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1117                 retval = -ENOMEM;
1118                 goto abort;
1119         }
1120
1121         /* Allocate buffer for printer status */
1122         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1123         if (!usblp->statusbuf) {
1124                 retval = -ENOMEM;
1125                 goto abort;
1126         }
1127
1128         /* Lookup quirks for this printer. */
1129         usblp->quirks = usblp_quirks(
1130                 le16_to_cpu(dev->descriptor.idVendor),
1131                 le16_to_cpu(dev->descriptor.idProduct));
1132
1133         /* Analyze and pick initial alternate settings and endpoints. */
1134         protocol = usblp_select_alts(usblp);
1135         if (protocol < 0) {
1136                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
1137                         le16_to_cpu(dev->descriptor.idVendor),
1138                         le16_to_cpu(dev->descriptor.idProduct));
1139                 retval = -ENODEV;
1140                 goto abort;
1141         }
1142
1143         /* Setup the selected alternate setting and endpoints. */
1144         if (usblp_set_protocol(usblp, protocol) < 0) {
1145                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1146                 goto abort;
1147         }
1148
1149         /* Retrieve and store the device ID string. */
1150         usblp_cache_device_id_string(usblp);
1151         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1152         if (retval)
1153                 goto abort_intfdata;
1154
1155 #ifdef DEBUG
1156         usblp_check_status(usblp, 0);
1157 #endif
1158
1159         usb_set_intfdata (intf, usblp);
1160
1161         usblp->present = 1;
1162
1163         retval = usb_register_dev(intf, &usblp_class);
1164         if (retval) {
1165                 printk(KERN_ERR "usblp: Not able to get a minor"
1166                     " (base %u, slice default): %d\n",
1167                     USBLP_MINOR_BASE, retval);
1168                 goto abort_intfdata;
1169         }
1170         usblp->minor = intf->minor;
1171         printk(KERN_INFO "usblp%d: USB %sdirectional printer dev %d "
1172                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1173                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1174                 usblp->ifnum,
1175                 usblp->protocol[usblp->current_protocol].alt_setting,
1176                 usblp->current_protocol,
1177                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1178                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1179
1180         return 0;
1181
1182 abort_intfdata:
1183         usb_set_intfdata (intf, NULL);
1184         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1185 abort:
1186         kfree(usblp->readbuf);
1187         kfree(usblp->statusbuf);
1188         kfree(usblp->device_id_string);
1189         kfree(usblp);
1190 abort_ret:
1191         return retval;
1192 }
1193
1194 /*
1195  * We are a "new" style driver with usb_device_id table,
1196  * but our requirements are too intricate for simple match to handle.
1197  *
1198  * The "proto_bias" option may be used to specify the preferred protocol
1199  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1200  * supports the preferred protocol, then we bind to it.
1201  *
1202  * The best interface for us is 7/1/2, because it is compatible
1203  * with a stream of characters. If we find it, we bind to it.
1204  *
1205  * Note that the people from hpoj.sourceforge.net need to be able to
1206  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1207  *
1208  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1209  * stream-compatible, because this matches the behaviour of the old code.
1210  *
1211  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1212  */
1213 static int usblp_select_alts(struct usblp *usblp)
1214 {
1215         struct usb_interface *if_alt;
1216         struct usb_host_interface *ifd;
1217         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1218         int p, i, e;
1219
1220         if_alt = usblp->intf;
1221
1222         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1223                 usblp->protocol[p].alt_setting = -1;
1224
1225         /* Find out what we have. */
1226         for (i = 0; i < if_alt->num_altsetting; i++) {
1227                 ifd = &if_alt->altsetting[i];
1228
1229                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1230                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1231                                 continue;
1232
1233                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1234                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1235                         continue;
1236
1237                 /* Look for bulk OUT and IN endpoints. */
1238                 epwrite = epread = NULL;
1239                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1240                         epd = &ifd->endpoint[e].desc;
1241
1242                         if (usb_endpoint_is_bulk_out(epd))
1243                                 if (!epwrite)
1244                                         epwrite = epd;
1245
1246                         if (usb_endpoint_is_bulk_in(epd))
1247                                 if (!epread)
1248                                         epread = epd;
1249                 }
1250
1251                 /* Ignore buggy hardware without the right endpoints. */
1252                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1253                         continue;
1254
1255                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1256                  * and buggy bidirectional printers. */
1257                 if (ifd->desc.bInterfaceProtocol == 1) {
1258                         epread = NULL;
1259                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1260                         printk(KERN_INFO "usblp%d: Disabling reads from "
1261                             "problematic bidirectional printer\n",
1262                             usblp->minor);
1263                         epread = NULL;
1264                 }
1265
1266                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1267                                 ifd->desc.bAlternateSetting;
1268                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1269                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1270         }
1271
1272         /* If our requested protocol is supported, then use it. */
1273         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1274             proto_bias <= USBLP_LAST_PROTOCOL &&
1275             usblp->protocol[proto_bias].alt_setting != -1)
1276                 return proto_bias;
1277
1278         /* Ordering is important here. */
1279         if (usblp->protocol[2].alt_setting != -1)
1280                 return 2;
1281         if (usblp->protocol[1].alt_setting != -1)
1282                 return 1;
1283         if (usblp->protocol[3].alt_setting != -1)
1284                 return 3;
1285
1286         /* If nothing is available, then don't bind to this device. */
1287         return -1;
1288 }
1289
1290 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1291 {
1292         int r, alts;
1293
1294         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1295                 return -EINVAL;
1296
1297         alts = usblp->protocol[protocol].alt_setting;
1298         if (alts < 0)
1299                 return -EINVAL;
1300         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1301         if (r < 0) {
1302                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1303                         alts, usblp->ifnum);
1304                 return r;
1305         }
1306
1307         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1308         usblp->current_protocol = protocol;
1309         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1310         return 0;
1311 }
1312
1313 /* Retrieves and caches device ID string.
1314  * Returns length, including length bytes but not null terminator.
1315  * On error, returns a negative errno value. */
1316 static int usblp_cache_device_id_string(struct usblp *usblp)
1317 {
1318         int err, length;
1319
1320         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1321         if (err < 0) {
1322                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1323                         usblp->minor, err);
1324                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1325                 return -EIO;
1326         }
1327
1328         /* First two bytes are length in big-endian.
1329          * They count themselves, and we copy them into
1330          * the user's buffer. */
1331         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1332         if (length < 2)
1333                 length = 2;
1334         else if (length >= USBLP_DEVICE_ID_SIZE)
1335                 length = USBLP_DEVICE_ID_SIZE - 1;
1336         usblp->device_id_string[length] = '\0';
1337
1338         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1339                 usblp->minor, length, &usblp->device_id_string[2]);
1340
1341         return length;
1342 }
1343
1344 static void usblp_disconnect(struct usb_interface *intf)
1345 {
1346         struct usblp *usblp = usb_get_intfdata (intf);
1347
1348         usb_deregister_dev(intf, &usblp_class);
1349
1350         if (!usblp || !usblp->dev) {
1351                 dev_err(&intf->dev, "bogus disconnect\n");
1352                 BUG ();
1353         }
1354
1355         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1356
1357         mutex_lock (&usblp_mutex);
1358         mutex_lock (&usblp->mut);
1359         usblp->present = 0;
1360         wake_up(&usblp->wwait);
1361         wake_up(&usblp->rwait);
1362         usb_set_intfdata (intf, NULL);
1363
1364         usblp_unlink_urbs(usblp);
1365         mutex_unlock (&usblp->mut);
1366
1367         if (!usblp->used)
1368                 usblp_cleanup (usblp);
1369         mutex_unlock (&usblp_mutex);
1370 }
1371
1372 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1373 {
1374         struct usblp *usblp = usb_get_intfdata (intf);
1375
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         r = handle_bidir (usblp);
1392
1393         return r;
1394 }
1395
1396 static const struct usb_device_id usblp_ids[] = {
1397         { USB_DEVICE_INFO(7, 1, 1) },
1398         { USB_DEVICE_INFO(7, 1, 2) },
1399         { USB_DEVICE_INFO(7, 1, 3) },
1400         { USB_INTERFACE_INFO(7, 1, 1) },
1401         { USB_INTERFACE_INFO(7, 1, 2) },
1402         { USB_INTERFACE_INFO(7, 1, 3) },
1403         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1404         { }                                             /* Terminating entry */
1405 };
1406
1407 MODULE_DEVICE_TABLE (usb, usblp_ids);
1408
1409 static struct usb_driver usblp_driver = {
1410         .name =         "usblp",
1411         .probe =        usblp_probe,
1412         .disconnect =   usblp_disconnect,
1413         .suspend =      usblp_suspend,
1414         .resume =       usblp_resume,
1415         .id_table =     usblp_ids,
1416         .supports_autosuspend = 1,
1417 };
1418
1419 static int __init usblp_init(void)
1420 {
1421         return usb_register(&usblp_driver);
1422 }
1423
1424 static void __exit usblp_exit(void)
1425 {
1426         usb_deregister(&usblp_driver);
1427 }
1428
1429 module_init(usblp_init);
1430 module_exit(usblp_exit);
1431
1432 MODULE_AUTHOR( DRIVER_AUTHOR );
1433 MODULE_DESCRIPTION( DRIVER_DESC );
1434 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1435 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1436 MODULE_LICENSE("GPL");