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