drivers/usb/class/usblp.c

   1 /*
   2  * usblp.c
   3  *
   4  * Copyright (c) 1999 Michael Gee       <michael@linuxspecific.com>
   5  * Copyright (c) 1999 Pavel Machek      <pavel@ucw.cz>
   6  * Copyright (c) 2000 Randy Dunlap      <rdunlap@xenotime.net>
   7  * Copyright (c) 2000 Vojtech Pavlik    <vojtech@suse.cz>
   8  # Copyright (c) 2001 Pete Zaitcev      <zaitcev@redhat.com>
   9  # Copyright (c) 2001 David Paschal     <paschal@rcsis.com>
  10  * Copyright (c) 2006 Oliver Neukum     <oliver@neukum.name>
  11  *
  12  * USB Printer Device Class driver for USB printers and printer cables
  13  *
  14  * Sponsored by SuSE
  15  *
  16  * ChangeLog:
  17  *      v0.1 - thorough cleaning, URBification, almost a rewrite
  18  *      v0.2 - some more cleanups
  19  *      v0.3 - cleaner again, waitqueue fixes
  20  *      v0.4 - fixes in unidirectional mode
  21  *      v0.5 - add DEVICE_ID string support
  22  *      v0.6 - never time out
  23  *      v0.7 - fixed bulk-IN read and poll (David Paschal)
  24  *      v0.8 - add devfs support
  25  *      v0.9 - fix unplug-while-open paths
  26  *      v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
  27  *      v0.11 - add proto_bias option (Pete Zaitcev)
  28  *      v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
  29  *      v0.13 - alloc space for statusbuf (<status> not on stack);
  30  *              use usb_alloc_coherent() for read buf & write buf;
  31  *      none  - Maintained in Linux kernel after v0.13
  32  */
  33
  34 /*
  35  * This program is free software; you can redistribute it and/or modify
  36  * it under the terms of the GNU General Public License as published by
  37  * the Free Software Foundation; either version 2 of the License, or
  38  * (at your option) any later version.
  39  *
  40  * This program is distributed in the hope that it will be useful,
  41  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  42  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  43  * GNU General Public License for more details.
  44  *
  45  * You should have received a copy of the GNU General Public License
  46  * along with this program; if not, write to the Free Software
  47  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  48  */
  49
  50 #include <linux/module.h>
  51 #include <linux/kernel.h>
  52 #include <linux/sched.h>
  53 #include <linux/signal.h>
  54 #include <linux/poll.h>
  55 #include <linux/init.h>
  56 #include <linux/slab.h>
  57 #include <linux/lp.h>
  58 #include <linux/mutex.h>
  59 #undef DEBUG
  60 #include <linux/usb.h>
  61
  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           no_paper;               /* Paper Out happened */
 167         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 168                                                         /* first 2 bytes are (big-endian) length */
 169 };
 170
 171 #ifdef DEBUG
 172 static void usblp_dump(struct usblp *usblp)
 173 {
 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         retval = usb_control_msg(usblp->dev,
 262                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 263                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
 264         dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d",
 265                 request, !!dir, recip, value, index, len, retval);
 266         return retval < 0 ? retval : 0;
 267 }
 268
 269 #define usblp_read_status(usblp, status)\
 270         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 271 #define usblp_get_id(usblp, config, id, maxlen)\
 272         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 273 #define usblp_reset(usblp)\
 274         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 275
 276 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
 277         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
 278
 279 /*
 280  * See the description for usblp_select_alts() below for the usage
 281  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
 282  * case of any trouble.
 283  */
 284 static int proto_bias = -1;
 285
 286 /*
 287  * URB callback.
 288  */
 289
 290 static void usblp_bulk_read(struct urb *urb)
 291 {
 292         struct usblp *usblp = urb->context;
 293         int status = urb->status;
 294
 295         if (usblp->present && usblp->used) {
 296                 if (status)
 297                         printk(KERN_WARNING "usblp%d: "
 298                             "nonzero read bulk status received: %d\n",
 299                             usblp->minor, status);
 300         }
 301         spin_lock(&usblp->lock);
 302         if (status < 0)
 303                 usblp->rstatus = status;
 304         else
 305                 usblp->rstatus = urb->actual_length;
 306         usblp->rcomplete = 1;
 307         wake_up(&usblp->rwait);
 308         spin_unlock(&usblp->lock);
 309
 310         usb_free_urb(urb);
 311 }
 312
 313 static void usblp_bulk_write(struct urb *urb)
 314 {
 315         struct usblp *usblp = urb->context;
 316         int status = urb->status;
 317
 318         if (usblp->present && usblp->used) {
 319                 if (status)
 320                         printk(KERN_WARNING "usblp%d: "
 321                             "nonzero write bulk status received: %d\n",
 322                             usblp->minor, status);
 323         }
 324         spin_lock(&usblp->lock);
 325         if (status < 0)
 326                 usblp->wstatus = status;
 327         else
 328                 usblp->wstatus = urb->actual_length;
 329         usblp->no_paper = 0;
 330         usblp->wcomplete = 1;
 331         wake_up(&usblp->wwait);
 332         spin_unlock(&usblp->lock);
 333
 334         usb_free_urb(urb);
 335 }
 336
 337 /*
 338  * Get and print printer errors.
 339  */
 340
 341 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 342
 343 static int usblp_check_status(struct usblp *usblp, int err)
 344 {
 345         unsigned char status, newerr = 0;
 346         int error;
 347
 348         mutex_lock(&usblp->mut);
 349         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 350                 mutex_unlock(&usblp->mut);
 351                 if (printk_ratelimit())
 352                         printk(KERN_ERR
 353                                 "usblp%d: error %d reading printer status\n",
 354                                 usblp->minor, error);
 355                 return 0;
 356         }
 357         status = *usblp->statusbuf;
 358         mutex_unlock(&usblp->mut);
 359
 360         if (~status & LP_PERRORP)
 361                 newerr = 3;
 362         if (status & LP_POUTPA)
 363                 newerr = 1;
 364         if (~status & LP_PSELECD)
 365                 newerr = 2;
 366
 367         if (newerr != err) {
 368                 printk(KERN_INFO "usblp%d: %s\n",
 369                    usblp->minor, usblp_messages[newerr]);
 370         }
 371
 372         return newerr;
 373 }
 374
 375 static int handle_bidir(struct usblp *usblp)
 376 {
 377         if (usblp->bidir && usblp->used) {
 378                 if (usblp_submit_read(usblp) < 0)
 379                         return -EIO;
 380         }
 381         return 0;
 382 }
 383
 384 /*
 385  * File op functions.
 386  */
 387
 388 static int usblp_open(struct inode *inode, struct file *file)
 389 {
 390         int minor = iminor(inode);
 391         struct usblp *usblp;
 392         struct usb_interface *intf;
 393         int retval;
 394
 395         if (minor < 0)
 396                 return -ENODEV;
 397
 398         mutex_lock(&usblp_mutex);
 399
 400         retval = -ENODEV;
 401         intf = usb_find_interface(&usblp_driver, minor);
 402         if (!intf)
 403                 goto out;
 404         usblp = usb_get_intfdata(intf);
 405         if (!usblp || !usblp->dev || !usblp->present)
 406                 goto out;
 407
 408         retval = -EBUSY;
 409         if (usblp->used)
 410                 goto out;
 411
 412         /*
 413          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 414          *  - We do not want persistent state which close(2) does not clear
 415          *  - It is not used anyway, according to CUPS people
 416          */
 417
 418         retval = usb_autopm_get_interface(intf);
 419         if (retval < 0)
 420                 goto out;
 421         usblp->used = 1;
 422         file->private_data = usblp;
 423
 424         usblp->wcomplete = 1; /* we begin writeable */
 425         usblp->wstatus = 0;
 426         usblp->rcomplete = 0;
 427
 428         if (handle_bidir(usblp) < 0) {
 429                 usb_autopm_put_interface(intf);
 430                 usblp->used = 0;
 431                 file->private_data = NULL;
 432                 retval = -EIO;
 433         }
 434 out:
 435         mutex_unlock(&usblp_mutex);
 436         return retval;
 437 }
 438
 439 static void usblp_cleanup(struct usblp *usblp)
 440 {
 441         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 442
 443         kfree(usblp->readbuf);
 444         kfree(usblp->device_id_string);
 445         kfree(usblp->statusbuf);
 446         kfree(usblp);
 447 }
 448
 449 static void usblp_unlink_urbs(struct usblp *usblp)
 450 {
 451         usb_kill_anchored_urbs(&usblp->urbs);
 452 }
 453
 454 static int usblp_release(struct inode *inode, struct file *file)
 455 {
 456         struct usblp *usblp = file->private_data;
 457
 458         usblp->flags &= ~LP_ABORT;
 459
 460         mutex_lock(&usblp_mutex);
 461         usblp->used = 0;
 462         if (usblp->present) {
 463                 usblp_unlink_urbs(usblp);
 464                 usb_autopm_put_interface(usblp->intf);
 465         } else          /* finish cleanup from disconnect */
 466                 usblp_cleanup(usblp);
 467         mutex_unlock(&usblp_mutex);
 468         return 0;
 469 }
 470
 471 /* No kernel lock - fine */
 472 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
 473 {
 474         int ret;
 475         unsigned long flags;
 476
 477         struct usblp *usblp = file->private_data;
 478         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 479         poll_wait(file, &usblp->rwait, wait);
 480         poll_wait(file, &usblp->wwait, wait);
 481         spin_lock_irqsave(&usblp->lock, flags);
 482         ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
 483            ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
 484         spin_unlock_irqrestore(&usblp->lock, flags);
 485         return ret;
 486 }
 487
 488 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 489 {
 490         struct usblp *usblp = file->private_data;
 491         int length, err, i;
 492         unsigned char newChannel;
 493         int status;
 494         int twoints[2];
 495         int retval = 0;
 496
 497         mutex_lock(&usblp->mut);
 498         if (!usblp->present) {
 499                 retval = -ENODEV;
 500                 goto done;
 501         }
 502
 503         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
 504                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 505
 506         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 507
 508                 switch (_IOC_NR(cmd)) {
 509
 510                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 511                         if (_IOC_DIR(cmd) != _IOC_READ) {
 512                                 retval = -EINVAL;
 513                                 goto done;
 514                         }
 515
 516                         length = usblp_cache_device_id_string(usblp);
 517                         if (length < 0) {
 518                                 retval = length;
 519                                 goto done;
 520                         }
 521                         if (length > _IOC_SIZE(cmd))
 522                                 length = _IOC_SIZE(cmd); /* truncate */
 523
 524                         if (copy_to_user((void __user *) arg,
 525                                         usblp->device_id_string,
 526                                         (unsigned long) length)) {
 527                                 retval = -EFAULT;
 528                                 goto done;
 529                         }
 530
 531                         break;
 532
 533                 case IOCNR_GET_PROTOCOLS:
 534                         if (_IOC_DIR(cmd) != _IOC_READ ||
 535                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 536                                 retval = -EINVAL;
 537                                 goto done;
 538                         }
 539
 540                         twoints[0] = usblp->current_protocol;
 541                         twoints[1] = 0;
 542                         for (i = USBLP_FIRST_PROTOCOL;
 543                              i <= USBLP_LAST_PROTOCOL; i++) {
 544                                 if (usblp->protocol[i].alt_setting >= 0)
 545                                         twoints[1] |= (1<<i);
 546                         }
 547
 548                         if (copy_to_user((void __user *)arg,
 549                                         (unsigned char *)twoints,
 550                                         sizeof(twoints))) {
 551                                 retval = -EFAULT;
 552                                 goto done;
 553                         }
 554
 555                         break;
 556
 557                 case IOCNR_SET_PROTOCOL:
 558                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
 559                                 retval = -EINVAL;
 560                                 goto done;
 561                         }
 562
 563 #ifdef DEBUG
 564                         if (arg == -10) {
 565                                 usblp_dump(usblp);
 566                                 break;
 567                         }
 568 #endif
 569
 570                         usblp_unlink_urbs(usblp);
 571                         retval = usblp_set_protocol(usblp, arg);
 572                         if (retval < 0) {
 573                                 usblp_set_protocol(usblp,
 574                                         usblp->current_protocol);
 575                         }
 576                         break;
 577
 578                 case IOCNR_HP_SET_CHANNEL:
 579                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
 580                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 581                             usblp->quirks & USBLP_QUIRK_BIDIR) {
 582                                 retval = -EINVAL;
 583                                 goto done;
 584                         }
 585
 586                         err = usblp_hp_channel_change_request(usblp,
 587                                 arg, &newChannel);
 588                         if (err < 0) {
 589                                 dev_err(&usblp->dev->dev,
 590                                         "usblp%d: error = %d setting "
 591                                         "HP channel\n",
 592                                         usblp->minor, err);
 593                                 retval = -EIO;
 594                                 goto done;
 595                         }
 596
 597                         dbg("usblp%d requested/got HP channel %ld/%d",
 598                                 usblp->minor, arg, newChannel);
 599                         break;
 600
 601                 case IOCNR_GET_BUS_ADDRESS:
 602                         if (_IOC_DIR(cmd) != _IOC_READ ||
 603                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 604                                 retval = -EINVAL;
 605                                 goto done;
 606                         }
 607
 608                         twoints[0] = usblp->dev->bus->busnum;
 609                         twoints[1] = usblp->dev->devnum;
 610                         if (copy_to_user((void __user *)arg,
 611                                         (unsigned char *)twoints,
 612                                         sizeof(twoints))) {
 613                                 retval = -EFAULT;
 614                                 goto done;
 615                         }
 616
 617                         dbg("usblp%d is bus=%d, device=%d",
 618                                 usblp->minor, twoints[0], twoints[1]);
 619                         break;
 620
 621                 case IOCNR_GET_VID_PID:
 622                         if (_IOC_DIR(cmd) != _IOC_READ ||
 623                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 624                                 retval = -EINVAL;
 625                                 goto done;
 626                         }
 627
 628                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 629                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 630                         if (copy_to_user((void __user *)arg,
 631                                         (unsigned char *)twoints,
 632                                         sizeof(twoints))) {
 633                                 retval = -EFAULT;
 634                                 goto done;
 635                         }
 636
 637                         dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
 638                                 usblp->minor, twoints[0], twoints[1]);
 639                         break;
 640
 641                 case IOCNR_SOFT_RESET:
 642                         if (_IOC_DIR(cmd) != _IOC_NONE) {
 643                                 retval = -EINVAL;
 644                                 goto done;
 645                         }
 646                         retval = usblp_reset(usblp);
 647                         break;
 648                 default:
 649                         retval = -ENOTTY;
 650                 }
 651         else    /* old-style ioctl value */
 652                 switch (cmd) {
 653
 654                 case LPGETSTATUS:
 655                         if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
 656                                 if (printk_ratelimit())
 657                                         printk(KERN_ERR "usblp%d:"
 658                                             "failed reading printer status (%d)\n",
 659                                             usblp->minor, retval);
 660                                 retval = -EIO;
 661                                 goto done;
 662                         }
 663                         status = *usblp->statusbuf;
 664                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 665                                 retval = -EFAULT;
 666                         break;
 667
 668                 case LPABORT:
 669                         if (arg)
 670                                 usblp->flags |= LP_ABORT;
 671                         else
 672                                 usblp->flags &= ~LP_ABORT;
 673                         break;
 674
 675                 default:
 676                         retval = -ENOTTY;
 677                 }
 678
 679 done:
 680         mutex_unlock(&usblp->mut);
 681         return retval;
 682 }
 683
 684 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 685 {
 686         struct urb *urb;
 687         char *writebuf;
 688
 689         if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
 690                 return NULL;
 691         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
 692                 kfree(writebuf);
 693                 return NULL;
 694         }
 695
 696         usb_fill_bulk_urb(urb, usblp->dev,
 697                 usb_sndbulkpipe(usblp->dev,
 698                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 699                 writebuf, transfer_length, usblp_bulk_write, usblp);
 700         urb->transfer_flags |= URB_FREE_BUFFER;
 701
 702         return urb;
 703 }
 704
 705 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 706 {
 707         struct usblp *usblp = file->private_data;
 708         struct urb *writeurb;
 709         int rv;
 710         int transfer_length;
 711         ssize_t writecount = 0;
 712
 713         if (mutex_lock_interruptible(&usblp->wmut)) {
 714                 rv = -EINTR;
 715                 goto raise_biglock;
 716         }
 717         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 718                 goto raise_wait;
 719
 720         while (writecount < count) {
 721                 /*
 722                  * Step 1: Submit next block.
 723                  */
 724                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 725                         transfer_length = USBLP_BUF_SIZE;
 726
 727                 rv = -ENOMEM;
 728                 if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
 729                         goto raise_urb;
 730                 usb_anchor_urb(writeurb, &usblp->urbs);
 731
 732                 if (copy_from_user(writeurb->transfer_buffer,
 733                                    buffer + writecount, transfer_length)) {
 734                         rv = -EFAULT;
 735                         goto raise_badaddr;
 736                 }
 737
 738                 spin_lock_irq(&usblp->lock);
 739                 usblp->wcomplete = 0;
 740                 spin_unlock_irq(&usblp->lock);
 741                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 742                         usblp->wstatus = 0;
 743                         spin_lock_irq(&usblp->lock);
 744                         usblp->no_paper = 0;
 745                         usblp->wcomplete = 1;
 746                         wake_up(&usblp->wwait);
 747                         spin_unlock_irq(&usblp->lock);
 748                         if (rv != -ENOMEM)
 749                                 rv = -EIO;
 750                         goto raise_submit;
 751                 }
 752
 753                 /*
 754                  * Step 2: Wait for transfer to end, collect results.
 755                  */
 756                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 757                 if (rv < 0) {
 758                         if (rv == -EAGAIN) {
 759                                 /* Presume that it's going to complete well. */
 760                                 writecount += transfer_length;
 761                         }
 762                         if (rv == -ENOSPC) {
 763                                 spin_lock_irq(&usblp->lock);
 764                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 765                                 spin_unlock_irq(&usblp->lock);
 766                                 writecount += transfer_length;
 767                         }
 768                         /* Leave URB dangling, to be cleaned on close. */
 769                         goto collect_error;
 770                 }
 771
 772                 if (usblp->wstatus < 0) {
 773                         rv = -EIO;
 774                         goto collect_error;
 775                 }
 776                 /*
 777                  * This is critical: it must be our URB, not other writer's.
 778                  * The wmut exists mainly to cover us here.
 779                  */
 780                 writecount += usblp->wstatus;
 781         }
 782
 783         mutex_unlock(&usblp->wmut);
 784         return writecount;
 785
 786 raise_submit:
 787 raise_badaddr:
 788         usb_unanchor_urb(writeurb);
 789         usb_free_urb(writeurb);
 790 raise_urb:
 791 raise_wait:
 792 collect_error:          /* Out of raise sequence */
 793         mutex_unlock(&usblp->wmut);
 794 raise_biglock:
 795         return writecount ? writecount : rv;
 796 }
 797
 798 /*
 799  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 800  * error, etc. This is the historical behaviour. In all such cases we return
 801  * EIO, and applications loop in order to get the new read going.
 802  */
 803 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 804 {
 805         struct usblp *usblp = file->private_data;
 806         ssize_t count;
 807         ssize_t avail;
 808         int rv;
 809
 810         if (!usblp->bidir)
 811                 return -EINVAL;
 812
 813         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 814         if (rv < 0)
 815                 return rv;
 816
 817         if ((avail = usblp->rstatus) < 0) {
 818                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 819                     usblp->minor, (int)avail);
 820                 usblp_submit_read(usblp);
 821                 count = -EIO;
 822                 goto done;
 823         }
 824
 825         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 826         if (count != 0 &&
 827             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 828                 count = -EFAULT;
 829                 goto done;
 830         }
 831
 832         if ((usblp->readcount += count) == avail) {
 833                 if (usblp_submit_read(usblp) < 0) {
 834                         /* We don't want to leak USB return codes into errno. */
 835                         if (count == 0)
 836                                 count = -EIO;
 837                         goto done;
 838                 }
 839         }
 840
 841 done:
 842         mutex_unlock(&usblp->mut);
 843         return count;
 844 }
 845
 846 /*
 847  * Wait for the write path to come idle.
 848  * This is called under the ->wmut, so the idle path stays idle.
 849  *
 850  * Our write path has a peculiar property: it does not buffer like a tty,
 851  * but waits for the write to succeed. This allows our ->release to bug out
 852  * without waiting for writes to drain. But it obviously does not work
 853  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 854  * select(2) or poll(2) to wait for the buffer to drain before closing.
 855  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 856  */
 857 static int usblp_wwait(struct usblp *usblp, int nonblock)
 858 {
 859         DECLARE_WAITQUEUE(waita, current);
 860         int rc;
 861         int err = 0;
 862
 863         add_wait_queue(&usblp->wwait, &waita);
 864         for (;;) {
 865                 set_current_state(TASK_INTERRUPTIBLE);
 866                 if (mutex_lock_interruptible(&usblp->mut)) {
 867                         rc = -EINTR;
 868                         break;
 869                 }
 870                 rc = usblp_wtest(usblp, nonblock);
 871                 mutex_unlock(&usblp->mut);
 872                 if (rc <= 0)
 873                         break;
 874
 875                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 876                         if (usblp->flags & LP_ABORT) {
 877                                 err = usblp_check_status(usblp, err);
 878                                 if (err == 1) { /* Paper out */
 879                                         rc = -ENOSPC;
 880                                         break;
 881                                 }
 882                         } else {
 883                                 /* Prod the printer, Gentoo#251237. */
 884                                 mutex_lock(&usblp->mut);
 885                                 usblp_read_status(usblp, usblp->statusbuf);
 886                                 mutex_unlock(&usblp->mut);
 887                         }
 888                 }
 889         }
 890         set_current_state(TASK_RUNNING);
 891         remove_wait_queue(&usblp->wwait, &waita);
 892         return rc;
 893 }
 894
 895 static int usblp_wtest(struct usblp *usblp, int nonblock)
 896 {
 897         unsigned long flags;
 898
 899         if (!usblp->present)
 900                 return -ENODEV;
 901         if (signal_pending(current))
 902                 return -EINTR;
 903         spin_lock_irqsave(&usblp->lock, flags);
 904         if (usblp->wcomplete) {
 905                 spin_unlock_irqrestore(&usblp->lock, flags);
 906                 return 0;
 907         }
 908         spin_unlock_irqrestore(&usblp->lock, flags);
 909         if (nonblock)
 910                 return -EAGAIN;
 911         return 1;
 912 }
 913
 914 /*
 915  * Wait for read bytes to become available. This probably should have been
 916  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 917  * name for functions which lock and return.
 918  *
 919  * We do not use wait_event_interruptible because it makes locking iffy.
 920  */
 921 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 922 {
 923         DECLARE_WAITQUEUE(waita, current);
 924         int rc;
 925
 926         add_wait_queue(&usblp->rwait, &waita);
 927         for (;;) {
 928                 if (mutex_lock_interruptible(&usblp->mut)) {
 929                         rc = -EINTR;
 930                         break;
 931                 }
 932                 set_current_state(TASK_INTERRUPTIBLE);
 933                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 934                         mutex_unlock(&usblp->mut);
 935                         break;
 936                 }
 937                 if (rc == 0)    /* Keep it locked */
 938                         break;
 939                 mutex_unlock(&usblp->mut);
 940                 schedule();
 941         }
 942         set_current_state(TASK_RUNNING);
 943         remove_wait_queue(&usblp->rwait, &waita);
 944         return rc;
 945 }
 946
 947 static int usblp_rtest(struct usblp *usblp, int nonblock)
 948 {
 949         unsigned long flags;
 950
 951         if (!usblp->present)
 952                 return -ENODEV;
 953         if (signal_pending(current))
 954                 return -EINTR;
 955         spin_lock_irqsave(&usblp->lock, flags);
 956         if (usblp->rcomplete) {
 957                 spin_unlock_irqrestore(&usblp->lock, flags);
 958                 return 0;
 959         }
 960         spin_unlock_irqrestore(&usblp->lock, flags);
 961         if (nonblock)
 962                 return -EAGAIN;
 963         return 1;
 964 }
 965
 966 /*
 967  * Please check ->bidir and other such things outside for now.
 968  */
 969 static int usblp_submit_read(struct usblp *usblp)
 970 {
 971         struct urb *urb;
 972         unsigned long flags;
 973         int rc;
 974
 975         rc = -ENOMEM;
 976         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
 977                 goto raise_urb;
 978
 979         usb_fill_bulk_urb(urb, usblp->dev,
 980                 usb_rcvbulkpipe(usblp->dev,
 981                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
 982                 usblp->readbuf, USBLP_BUF_SIZE_IN,
 983                 usblp_bulk_read, usblp);
 984         usb_anchor_urb(urb, &usblp->urbs);
 985
 986         spin_lock_irqsave(&usblp->lock, flags);
 987         usblp->readcount = 0; /* XXX Why here? */
 988         usblp->rcomplete = 0;
 989         spin_unlock_irqrestore(&usblp->lock, flags);
 990         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
 991                 dbg("error submitting urb (%d)", rc);
 992                 spin_lock_irqsave(&usblp->lock, flags);
 993                 usblp->rstatus = rc;
 994                 usblp->rcomplete = 1;
 995                 spin_unlock_irqrestore(&usblp->lock, flags);
 996                 goto raise_submit;
 997         }
 998
 999         return 0;
1000
1001 raise_submit:
1002         usb_unanchor_urb(urb);
1003         usb_free_urb(urb);
1004 raise_urb:
1005         return rc;
1006 }
1007
1008 /*
1009  * Checks for printers that have quirks, such as requiring unidirectional
1010  * communication but reporting bidirectional; currently some HP printers
1011  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1012  * sent at each open (like some Epsons).
1013  * Returns 1 if found, 0 if not found.
1014  *
1015  * HP recommended that we use the bidirectional interface but
1016  * don't attempt any bulk IN transfers from the IN endpoint.
1017  * Here's some more detail on the problem:
1018  * The problem is not that it isn't bidirectional though. The problem
1019  * is that if you request a device ID, or status information, while
1020  * the buffers are full, the return data will end up in the print data
1021  * buffer. For example if you make sure you never request the device ID
1022  * while you are sending print data, and you don't try to query the
1023  * printer status every couple of milliseconds, you will probably be OK.
1024  */
1025 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1026 {
1027         int i;
1028
1029         for (i = 0; quirk_printers[i].vendorId; i++) {
1030                 if (vendor == quirk_printers[i].vendorId &&
1031                     product == quirk_printers[i].productId)
1032                         return quirk_printers[i].quirks;
1033         }
1034         return 0;
1035 }
1036
1037 static const struct file_operations usblp_fops = {
1038         .owner =        THIS_MODULE,
1039         .read =         usblp_read,
1040         .write =        usblp_write,
1041         .poll =         usblp_poll,
1042         .unlocked_ioctl =       usblp_ioctl,
1043         .compat_ioctl =         usblp_ioctl,
1044         .open =         usblp_open,
1045         .release =      usblp_release,
1046         .llseek =       noop_llseek,
1047 };
1048
1049 static char *usblp_devnode(struct device *dev, mode_t *mode)
1050 {
1051         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1052 }
1053
1054 static struct usb_class_driver usblp_class = {
1055         .name =         "lp%d",
1056         .devnode =      usblp_devnode,
1057         .fops =         &usblp_fops,
1058         .minor_base =   USBLP_MINOR_BASE,
1059 };
1060
1061 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1062 {
1063         struct usb_interface *intf = to_usb_interface(dev);
1064         struct usblp *usblp = usb_get_intfdata(intf);
1065
1066         if (usblp->device_id_string[0] == 0 &&
1067             usblp->device_id_string[1] == 0)
1068                 return 0;
1069
1070         return sprintf(buf, "%s", usblp->device_id_string+2);
1071 }
1072
1073 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1074
1075 static int usblp_probe(struct usb_interface *intf,
1076                        const struct usb_device_id *id)
1077 {
1078         struct usb_device *dev = interface_to_usbdev(intf);
1079         struct usblp *usblp;
1080         int protocol;
1081         int retval;
1082
1083         /* Malloc and start initializing usblp structure so we can use it
1084          * directly. */
1085         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1086         if (!usblp) {
1087                 retval = -ENOMEM;
1088                 goto abort_ret;
1089         }
1090         usblp->dev = dev;
1091         mutex_init(&usblp->wmut);
1092         mutex_init(&usblp->mut);
1093         spin_lock_init(&usblp->lock);
1094         init_waitqueue_head(&usblp->rwait);
1095         init_waitqueue_head(&usblp->wwait);
1096         init_usb_anchor(&usblp->urbs);
1097         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1098         usblp->intf = intf;
1099
1100         /* Malloc device ID string buffer to the largest expected length,
1101          * since we can re-query it on an ioctl and a dynamic string
1102          * could change in length. */
1103         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1104                 retval = -ENOMEM;
1105                 goto abort;
1106         }
1107
1108         /*
1109          * Allocate read buffer. We somewhat wastefully
1110          * malloc both regardless of bidirectionality, because the
1111          * alternate setting can be changed later via an ioctl.
1112          */
1113         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1114                 retval = -ENOMEM;
1115                 goto abort;
1116         }
1117
1118         /* Allocate buffer for printer status */
1119         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1120         if (!usblp->statusbuf) {
1121                 retval = -ENOMEM;
1122                 goto abort;
1123         }
1124
1125         /* Lookup quirks for this printer. */
1126         usblp->quirks = usblp_quirks(
1127                 le16_to_cpu(dev->descriptor.idVendor),
1128                 le16_to_cpu(dev->descriptor.idProduct));
1129
1130         /* Analyze and pick initial alternate settings and endpoints. */
1131         protocol = usblp_select_alts(usblp);
1132         if (protocol < 0) {
1133                 dbg("incompatible printer-class device 0x%4.4X/0x%4.4X",
1134                         le16_to_cpu(dev->descriptor.idVendor),
1135                         le16_to_cpu(dev->descriptor.idProduct));
1136                 retval = -ENODEV;
1137                 goto abort;
1138         }
1139
1140         /* Setup the selected alternate setting and endpoints. */
1141         if (usblp_set_protocol(usblp, protocol) < 0) {
1142                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1143                 goto abort;
1144         }
1145
1146         /* Retrieve and store the device ID string. */
1147         usblp_cache_device_id_string(usblp);
1148         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1149         if (retval)
1150                 goto abort_intfdata;
1151
1152 #ifdef DEBUG
1153         usblp_check_status(usblp, 0);
1154 #endif
1155
1156         usb_set_intfdata(intf, usblp);
1157
1158         usblp->present = 1;
1159
1160         retval = usb_register_dev(intf, &usblp_class);
1161         if (retval) {
1162                 printk(KERN_ERR "usblp: Not able to get a minor"
1163                     " (base %u, slice default): %d\n",
1164                     USBLP_MINOR_BASE, retval);
1165                 goto abort_intfdata;
1166         }
1167         usblp->minor = intf->minor;
1168         printk(KERN_INFO "usblp%d: USB %sdirectional printer dev %d "
1169                 "if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1170                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1171                 usblp->ifnum,
1172                 usblp->protocol[usblp->current_protocol].alt_setting,
1173                 usblp->current_protocol,
1174                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1175                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1176
1177         return 0;
1178
1179 abort_intfdata:
1180         usb_set_intfdata(intf, NULL);
1181         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1182 abort:
1183         kfree(usblp->readbuf);
1184         kfree(usblp->statusbuf);
1185         kfree(usblp->device_id_string);
1186         kfree(usblp);
1187 abort_ret:
1188         return retval;
1189 }
1190
1191 /*
1192  * We are a "new" style driver with usb_device_id table,
1193  * but our requirements are too intricate for simple match to handle.
1194  *
1195  * The "proto_bias" option may be used to specify the preferred protocol
1196  * for all USB printers (1=7/1/1, 2=7/1/2, 3=7/1/3).  If the device
1197  * supports the preferred protocol, then we bind to it.
1198  *
1199  * The best interface for us is 7/1/2, because it is compatible
1200  * with a stream of characters. If we find it, we bind to it.
1201  *
1202  * Note that the people from hpoj.sourceforge.net need to be able to
1203  * bind to 7/1/3 (MLC/1284.4), so we provide them ioctls for this purpose.
1204  *
1205  * Failing 7/1/2, we look for 7/1/3, even though it's probably not
1206  * stream-compatible, because this matches the behaviour of the old code.
1207  *
1208  * If nothing else, we bind to 7/1/1 - the unidirectional interface.
1209  */
1210 static int usblp_select_alts(struct usblp *usblp)
1211 {
1212         struct usb_interface *if_alt;
1213         struct usb_host_interface *ifd;
1214         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1215         int p, i, e;
1216
1217         if_alt = usblp->intf;
1218
1219         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1220                 usblp->protocol[p].alt_setting = -1;
1221
1222         /* Find out what we have. */
1223         for (i = 0; i < if_alt->num_altsetting; i++) {
1224                 ifd = &if_alt->altsetting[i];
1225
1226                 if (ifd->desc.bInterfaceClass != 7 || ifd->desc.bInterfaceSubClass != 1)
1227                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1228                                 continue;
1229
1230                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1231                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1232                         continue;
1233
1234                 /* Look for bulk OUT and IN endpoints. */
1235                 epwrite = epread = NULL;
1236                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1237                         epd = &ifd->endpoint[e].desc;
1238
1239                         if (usb_endpoint_is_bulk_out(epd))
1240                                 if (!epwrite)
1241                                         epwrite = epd;
1242
1243                         if (usb_endpoint_is_bulk_in(epd))
1244                                 if (!epread)
1245                                         epread = epd;
1246                 }
1247
1248                 /* Ignore buggy hardware without the right endpoints. */
1249                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1250                         continue;
1251
1252                 /* Turn off reads for 7/1/1 (unidirectional) interfaces
1253                  * and buggy bidirectional printers. */
1254                 if (ifd->desc.bInterfaceProtocol == 1) {
1255                         epread = NULL;
1256                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1257                         printk(KERN_INFO "usblp%d: Disabling reads from "
1258                             "problematic bidirectional printer\n",
1259                             usblp->minor);
1260                         epread = NULL;
1261                 }
1262
1263                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1264                                 ifd->desc.bAlternateSetting;
1265                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1266                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1267         }
1268
1269         /* If our requested protocol is supported, then use it. */
1270         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1271             proto_bias <= USBLP_LAST_PROTOCOL &&
1272             usblp->protocol[proto_bias].alt_setting != -1)
1273                 return proto_bias;
1274
1275         /* Ordering is important here. */
1276         if (usblp->protocol[2].alt_setting != -1)
1277                 return 2;
1278         if (usblp->protocol[1].alt_setting != -1)
1279                 return 1;
1280         if (usblp->protocol[3].alt_setting != -1)
1281                 return 3;
1282
1283         /* If nothing is available, then don't bind to this device. */
1284         return -1;
1285 }
1286
1287 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1288 {
1289         int r, alts;
1290
1291         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1292                 return -EINVAL;
1293
1294         alts = usblp->protocol[protocol].alt_setting;
1295         if (alts < 0)
1296                 return -EINVAL;
1297         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1298         if (r < 0) {
1299                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1300                         alts, usblp->ifnum);
1301                 return r;
1302         }
1303
1304         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1305         usblp->current_protocol = protocol;
1306         dbg("usblp%d set protocol %d", usblp->minor, protocol);
1307         return 0;
1308 }
1309
1310 /* Retrieves and caches device ID string.
1311  * Returns length, including length bytes but not null terminator.
1312  * On error, returns a negative errno value. */
1313 static int usblp_cache_device_id_string(struct usblp *usblp)
1314 {
1315         int err, length;
1316
1317         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1318         if (err < 0) {
1319                 dbg("usblp%d: error = %d reading IEEE-1284 Device ID string",
1320                         usblp->minor, err);
1321                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1322                 return -EIO;
1323         }
1324
1325         /* First two bytes are length in big-endian.
1326          * They count themselves, and we copy them into
1327          * the user's buffer. */
1328         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1329         if (length < 2)
1330                 length = 2;
1331         else if (length >= USBLP_DEVICE_ID_SIZE)
1332                 length = USBLP_DEVICE_ID_SIZE - 1;
1333         usblp->device_id_string[length] = '\0';
1334
1335         dbg("usblp%d Device ID string [len=%d]=\"%s\"",
1336                 usblp->minor, length, &usblp->device_id_string[2]);
1337
1338         return length;
1339 }
1340
1341 static void usblp_disconnect(struct usb_interface *intf)
1342 {
1343         struct usblp *usblp = usb_get_intfdata(intf);
1344
1345         usb_deregister_dev(intf, &usblp_class);
1346
1347         if (!usblp || !usblp->dev) {
1348                 dev_err(&intf->dev, "bogus disconnect\n");
1349                 BUG();
1350         }
1351
1352         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1353
1354         mutex_lock(&usblp_mutex);
1355         mutex_lock(&usblp->mut);
1356         usblp->present = 0;
1357         wake_up(&usblp->wwait);
1358         wake_up(&usblp->rwait);
1359         usb_set_intfdata(intf, NULL);
1360
1361         usblp_unlink_urbs(usblp);
1362         mutex_unlock(&usblp->mut);
1363
1364         if (!usblp->used)
1365                 usblp_cleanup(usblp);
1366         mutex_unlock(&usblp_mutex);
1367 }
1368
1369 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1370 {
1371         struct usblp *usblp = usb_get_intfdata(intf);
1372
1373         usblp_unlink_urbs(usblp);
1374 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1375         /* not strictly necessary, but just in case */
1376         wake_up(&usblp->wwait);
1377         wake_up(&usblp->rwait);
1378 #endif
1379
1380         return 0;
1381 }
1382
1383 static int usblp_resume(struct usb_interface *intf)
1384 {
1385         struct usblp *usblp = usb_get_intfdata(intf);
1386         int r;
1387
1388         r = handle_bidir(usblp);
1389
1390         return r;
1391 }
1392
1393 static const struct usb_device_id usblp_ids[] = {
1394         { USB_DEVICE_INFO(7, 1, 1) },
1395         { USB_DEVICE_INFO(7, 1, 2) },
1396         { USB_DEVICE_INFO(7, 1, 3) },
1397         { USB_INTERFACE_INFO(7, 1, 1) },
1398         { USB_INTERFACE_INFO(7, 1, 2) },
1399         { USB_INTERFACE_INFO(7, 1, 3) },
1400         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1401         { }                                             /* Terminating entry */
1402 };
1403
1404 MODULE_DEVICE_TABLE(usb, usblp_ids);
1405
1406 static struct usb_driver usblp_driver = {
1407         .name =         "usblp",
1408         .probe =        usblp_probe,
1409         .disconnect =   usblp_disconnect,
1410         .suspend =      usblp_suspend,
1411         .resume =       usblp_resume,
1412         .id_table =     usblp_ids,
1413         .supports_autosuspend = 1,
1414 };
1415
1416 static int __init usblp_init(void)
1417 {
1418         return usb_register(&usblp_driver);
1419 }
1420
1421 static void __exit usblp_exit(void)
1422 {
1423         usb_deregister(&usblp_driver);
1424 }
1425
1426 module_init(usblp_init);
1427 module_exit(usblp_exit);
1428
1429 MODULE_AUTHOR(DRIVER_AUTHOR);
1430 MODULE_DESCRIPTION(DRIVER_DESC);
1431 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1432 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1433 MODULE_LICENSE("GPL");