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_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         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("device_id_string=\"%s\"",
 194                 usblp->device_id_string ?
 195                         usblp->device_id_string + 2 :
 196                         (unsigned char *)"(null)");
 197 }
 198 #endif
 199
 200 /* Quirks: various printer quirks are handled by this table & its flags. */
 201
 202 struct quirk_printer_struct {
 203         __u16 vendorId;
 204         __u16 productId;
 205         unsigned int quirks;
 206 };
 207
 208 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 209 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 210 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
 211
 212 static const struct quirk_printer_struct quirk_printers[] = {
 213         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 214         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 215         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 216         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 217         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 218         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 219         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 220         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 221         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 222         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 223         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 224         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 225         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 226         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
 227         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 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_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         }
 405         usblp = usb_get_intfdata (intf);
 406         if (!usblp || !usblp->dev || !usblp->present)
 407                 goto out;
 408
 409         retval = -EBUSY;
 410         if (usblp->used)
 411                 goto out;
 412
 413         /*
 414          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 415          *  - We do not want persistent state which close(2) does not clear
 416          *  - It is not used anyway, according to CUPS people
 417          */
 418
 419         retval = usb_autopm_get_interface(intf);
 420         if (retval < 0)
 421                 goto out;
 422         usblp->used = 1;
 423         file->private_data = usblp;
 424
 425         usblp->wcomplete = 1; /* we begin writeable */
 426         usblp->wstatus = 0;
 427         usblp->rcomplete = 0;
 428
 429         if (handle_bidir(usblp) < 0) {
 430                 usb_autopm_put_interface(intf);
 431                 usblp->used = 0;
 432                 file->private_data = NULL;
 433                 retval = -EIO;
 434         }
 435 out:
 436         mutex_unlock (&usblp_mutex);
 437         return retval;
 438 }
 439
 440 static void usblp_cleanup (struct usblp *usblp)
 441 {
 442         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 443
 444         kfree(usblp->readbuf);
 445         kfree (usblp->device_id_string);
 446         kfree (usblp->statusbuf);
 447         kfree (usblp);
 448 }
 449
 450 static void usblp_unlink_urbs(struct usblp *usblp)
 451 {
 452         usb_kill_anchored_urbs(&usblp->urbs);
 453 }
 454
 455 static int usblp_release(struct inode *inode, struct file *file)
 456 {
 457         struct usblp *usblp = file->private_data;
 458
 459         usblp->flags &= ~LP_ABORT;
 460
 461         mutex_lock (&usblp_mutex);
 462         usblp->used = 0;
 463         if (usblp->present) {
 464                 usblp_unlink_urbs(usblp);
 465                 usb_autopm_put_interface(usblp->intf);
 466         } else          /* finish cleanup from disconnect */
 467                 usblp_cleanup (usblp);
 468         mutex_unlock (&usblp_mutex);
 469         return 0;
 470 }
 471
 472 /* No kernel lock - fine */
 473 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
 474 {
 475         int ret;
 476         unsigned long flags;
 477
 478         struct usblp *usblp = file->private_data;
 479         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 480         poll_wait(file, &usblp->rwait, wait);
 481         poll_wait(file, &usblp->wwait, wait);
 482         spin_lock_irqsave(&usblp->lock, flags);
 483         ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
 484            ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
 485         spin_unlock_irqrestore(&usblp->lock, flags);
 486         return ret;
 487 }
 488
 489 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 490 {
 491         struct usblp *usblp = file->private_data;
 492         int length, err, i;
 493         unsigned char newChannel;
 494         int status;
 495         int twoints[2];
 496         int retval = 0;
 497
 498         mutex_lock (&usblp->mut);
 499         if (!usblp->present) {
 500                 retval = -ENODEV;
 501                 goto done;
 502         }
 503
 504         dbg("usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)", cmd, _IOC_TYPE(cmd),
 505                 _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd) );
 506
 507         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 508
 509                 switch (_IOC_NR(cmd)) {
 510
 511                         case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 512                                 if (_IOC_DIR(cmd) != _IOC_READ) {
 513                                         retval = -EINVAL;
 514                                         goto done;
 515                                 }
 516
 517                                 length = usblp_cache_device_id_string(usblp);
 518                                 if (length < 0) {
 519                                         retval = length;
 520                                         goto done;
 521                                 }
 522                                 if (length > _IOC_SIZE(cmd))
 523                                         length = _IOC_SIZE(cmd); /* truncate */
 524
 525                                 if (copy_to_user((void __user *) arg,
 526                                                 usblp->device_id_string,
 527                                                 (unsigned long) length)) {
 528                                         retval = -EFAULT;
 529                                         goto done;
 530                                 }
 531
 532                                 break;
 533
 534                         case IOCNR_GET_PROTOCOLS:
 535                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 536                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 537                                         retval = -EINVAL;
 538                                         goto done;
 539                                 }
 540
 541                                 twoints[0] = usblp->current_protocol;
 542                                 twoints[1] = 0;
 543                                 for (i = USBLP_FIRST_PROTOCOL;
 544                                      i <= USBLP_LAST_PROTOCOL; i++) {
 545                                         if (usblp->protocol[i].alt_setting >= 0)
 546                                                 twoints[1] |= (1<<i);
 547                                 }
 548
 549                                 if (copy_to_user((void __user *)arg,
 550                                                 (unsigned char *)twoints,
 551                                                 sizeof(twoints))) {
 552                                         retval = -EFAULT;
 553                                         goto done;
 554                                 }
 555
 556                                 break;
 557
 558                         case IOCNR_SET_PROTOCOL:
 559                                 if (_IOC_DIR(cmd) != _IOC_WRITE) {
 560                                         retval = -EINVAL;
 561                                         goto done;
 562                                 }
 563
 564 #ifdef DEBUG
 565                                 if (arg == -10) {
 566                                         usblp_dump(usblp);
 567                                         break;
 568                                 }
 569 #endif
 570
 571                                 usblp_unlink_urbs(usblp);
 572                                 retval = usblp_set_protocol(usblp, arg);
 573                                 if (retval < 0) {
 574                                         usblp_set_protocol(usblp,
 575                                                 usblp->current_protocol);
 576                                 }
 577                                 break;
 578
 579                         case IOCNR_HP_SET_CHANNEL:
 580                                 if (_IOC_DIR(cmd) != _IOC_WRITE ||
 581                                     le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 582                                     usblp->quirks & USBLP_QUIRK_BIDIR) {
 583                                         retval = -EINVAL;
 584                                         goto done;
 585                                 }
 586
 587                                 err = usblp_hp_channel_change_request(usblp,
 588                                         arg, &newChannel);
 589                                 if (err < 0) {
 590                                         dev_err(&usblp->dev->dev,
 591                                                 "usblp%d: error = %d setting "
 592                                                 "HP channel\n",
 593                                                 usblp->minor, err);
 594                                         retval = -EIO;
 595                                         goto done;
 596                                 }
 597
 598                                 dbg("usblp%d requested/got HP channel %ld/%d",
 599                                         usblp->minor, arg, newChannel);
 600                                 break;
 601
 602                         case IOCNR_GET_BUS_ADDRESS:
 603                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 604                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 605                                         retval = -EINVAL;
 606                                         goto done;
 607                                 }
 608
 609                                 twoints[0] = usblp->dev->bus->busnum;
 610                                 twoints[1] = usblp->dev->devnum;
 611                                 if (copy_to_user((void __user *)arg,
 612                                                 (unsigned char *)twoints,
 613                                                 sizeof(twoints))) {
 614                                         retval = -EFAULT;
 615                                         goto done;
 616                                 }
 617
 618                                 dbg("usblp%d is bus=%d, device=%d",
 619                                         usblp->minor, twoints[0], twoints[1]);
 620                                 break;
 621
 622                         case IOCNR_GET_VID_PID:
 623                                 if (_IOC_DIR(cmd) != _IOC_READ ||
 624                                     _IOC_SIZE(cmd) < sizeof(twoints)) {
 625                                         retval = -EINVAL;
 626                                         goto done;
 627                                 }
 628
 629                                 twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 630                                 twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 631                                 if (copy_to_user((void __user *)arg,
 632                                                 (unsigned char *)twoints,
 633                                                 sizeof(twoints))) {
 634                                         retval = -EFAULT;
 635                                         goto done;
 636                                 }
 637
 638                                 dbg("usblp%d is VID=0x%4.4X, PID=0x%4.4X",
 639                                         usblp->minor, twoints[0], twoints[1]);
 640                                 break;
 641
 642                         case IOCNR_SOFT_RESET:
 643                                 if (_IOC_DIR(cmd) != _IOC_NONE) {
 644                                         retval = -EINVAL;
 645                                         goto done;
 646                                 }
 647                                 retval = usblp_reset(usblp);
 648                                 break;
 649                         default:
 650                                 retval = -ENOTTY;
 651                 }
 652         else    /* old-style ioctl value */
 653                 switch (cmd) {
 654
 655                         case LPGETSTATUS:
 656                                 if ((retval = usblp_read_status(usblp, usblp->statusbuf))) {
 657                                         if (printk_ratelimit())
 658                                                 printk(KERN_ERR "usblp%d:"
 659                                                     "failed reading printer status (%d)\n",
 660                                                     usblp->minor, retval);
 661                                         retval = -EIO;
 662                                         goto done;
 663                                 }
 664                                 status = *usblp->statusbuf;
 665                                 if (copy_to_user ((void __user *)arg, &status, sizeof(int)))
 666                                         retval = -EFAULT;
 667                                 break;
 668
 669                         case LPABORT:
 670                                 if (arg)
 671                                         usblp->flags |= LP_ABORT;
 672                                 else
 673                                         usblp->flags &= ~LP_ABORT;
 674                                 break;
 675
 676                         default:
 677                                 retval = -ENOTTY;
 678                 }
 679
 680 done:
 681         mutex_unlock (&usblp->mut);
 682         return retval;
 683 }
 684
 685 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 686 {
 687         struct urb *urb;
 688         char *writebuf;
 689
 690         if ((writebuf = kmalloc(transfer_length, GFP_KERNEL)) == NULL)
 691                 return NULL;
 692         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL) {
 693                 kfree(writebuf);
 694                 return NULL;
 695         }
 696
 697         usb_fill_bulk_urb(urb, usblp->dev,
 698                 usb_sndbulkpipe(usblp->dev,
 699                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 700                 writebuf, transfer_length, usblp_bulk_write, usblp);
 701         urb->transfer_flags |= URB_FREE_BUFFER;
 702
 703         return urb;
 704 }
 705
 706 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 707 {
 708         struct usblp *usblp = file->private_data;
 709         struct urb *writeurb;
 710         int rv;
 711         int transfer_length;
 712         ssize_t writecount = 0;
 713
 714         if (mutex_lock_interruptible(&usblp->wmut)) {
 715                 rv = -EINTR;
 716                 goto raise_biglock;
 717         }
 718         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 719                 goto raise_wait;
 720
 721         while (writecount < count) {
 722                 /*
 723                  * Step 1: Submit next block.
 724                  */
 725                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 726                         transfer_length = USBLP_BUF_SIZE;
 727
 728                 rv = -ENOMEM;
 729                 if ((writeurb = usblp_new_writeurb(usblp, transfer_length)) == NULL)
 730                         goto raise_urb;
 731                 usb_anchor_urb(writeurb, &usblp->urbs);
 732
 733                 if (copy_from_user(writeurb->transfer_buffer,
 734                                    buffer + writecount, transfer_length)) {
 735                         rv = -EFAULT;
 736                         goto raise_badaddr;
 737                 }
 738
 739                 spin_lock_irq(&usblp->lock);
 740                 usblp->wcomplete = 0;
 741                 spin_unlock_irq(&usblp->lock);
 742                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 743                         usblp->wstatus = 0;
 744                         spin_lock_irq(&usblp->lock);
 745                         usblp->no_paper = 0;
 746                         usblp->wcomplete = 1;
 747                         wake_up(&usblp->wwait);
 748                         spin_unlock_irq(&usblp->lock);
 749                         if (rv != -ENOMEM)
 750                                 rv = -EIO;
 751                         goto raise_submit;
 752                 }
 753
 754                 /*
 755                  * Step 2: Wait for transfer to end, collect results.
 756                  */
 757                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 758                 if (rv < 0) {
 759                         if (rv == -EAGAIN) {
 760                                 /* Presume that it's going to complete well. */
 761                                 writecount += transfer_length;
 762                         }
 763                         if (rv == -ENOSPC) {
 764                                 spin_lock_irq(&usblp->lock);
 765                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 766                                 spin_unlock_irq(&usblp->lock);
 767                                 writecount += transfer_length;
 768                         }
 769                         /* Leave URB dangling, to be cleaned on close. */
 770                         goto collect_error;
 771                 }
 772
 773                 if (usblp->wstatus < 0) {
 774                         rv = -EIO;
 775                         goto collect_error;
 776                 }
 777                 /*
 778                  * This is critical: it must be our URB, not other writer's.
 779                  * The wmut exists mainly to cover us here.
 780                  */
 781                 writecount += usblp->wstatus;
 782         }
 783
 784         mutex_unlock(&usblp->wmut);
 785         return writecount;
 786
 787 raise_submit:
 788 raise_badaddr:
 789         usb_unanchor_urb(writeurb);
 790         usb_free_urb(writeurb);
 791 raise_urb:
 792 raise_wait:
 793 collect_error:          /* Out of raise sequence */
 794         mutex_unlock(&usblp->wmut);
 795 raise_biglock:
 796         return writecount ? writecount : rv;
 797 }
 798
 799 /*
 800  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 801  * error, etc. This is the historical behaviour. In all such cases we return
 802  * EIO, and applications loop in order to get the new read going.
 803  */
 804 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 805 {
 806         struct usblp *usblp = file->private_data;
 807         ssize_t count;
 808         ssize_t avail;
 809         int rv;
 810
 811         if (!usblp->bidir)
 812                 return -EINVAL;
 813
 814         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 815         if (rv < 0)
 816                 return rv;
 817
 818         if ((avail = usblp->rstatus) < 0) {
 819                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 820                     usblp->minor, (int)avail);
 821                 usblp_submit_read(usblp);
 822                 count = -EIO;
 823                 goto done;
 824         }
 825
 826         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 827         if (count != 0 &&
 828             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 829                 count = -EFAULT;
 830                 goto done;
 831         }
 832
 833         if ((usblp->readcount += count) == avail) {
 834                 if (usblp_submit_read(usblp) < 0) {
 835                         /* We don't want to leak USB return codes into errno. */
 836                         if (count == 0)
 837                                 count = -EIO;
 838                         goto done;
 839                 }
 840         }
 841
 842 done:
 843         mutex_unlock (&usblp->mut);
 844         return count;
 845 }
 846
 847 /*
 848  * Wait for the write path to come idle.
 849  * This is called under the ->wmut, so the idle path stays idle.
 850  *
 851  * Our write path has a peculiar property: it does not buffer like a tty,
 852  * but waits for the write to succeed. This allows our ->release to bug out
 853  * without waiting for writes to drain. But it obviously does not work
 854  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 855  * select(2) or poll(2) to wait for the buffer to drain before closing.
 856  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 857  */
 858 static int usblp_wwait(struct usblp *usblp, int nonblock)
 859 {
 860         DECLARE_WAITQUEUE(waita, current);
 861         int rc;
 862         int err = 0;
 863
 864         add_wait_queue(&usblp->wwait, &waita);
 865         for (;;) {
 866                 set_current_state(TASK_INTERRUPTIBLE);
 867                 if (mutex_lock_interruptible(&usblp->mut)) {
 868                         rc = -EINTR;
 869                         break;
 870                 }
 871                 rc = usblp_wtest(usblp, nonblock);
 872                 mutex_unlock(&usblp->mut);
 873                 if (rc <= 0)
 874                         break;
 875
 876                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 877                         if (usblp->flags & LP_ABORT) {
 878                                 err = usblp_check_status(usblp, err);
 879                                 if (err == 1) { /* Paper out */
 880                                         rc = -ENOSPC;
 881                                         break;
 882                                 }
 883                         } else {
 884                                 /* Prod the printer, Gentoo#251237. */
 885                                 mutex_lock(&usblp->mut);
 886                                 usblp_read_status(usblp, usblp->statusbuf);
 887                                 mutex_unlock(&usblp->mut);
 888                         }
 889                 }
 890         }
 891         set_current_state(TASK_RUNNING);
 892         remove_wait_queue(&usblp->wwait, &waita);
 893         return rc;
 894 }
 895
 896 static int usblp_wtest(struct usblp *usblp, int nonblock)
 897 {
 898         unsigned long flags;
 899
 900         if (!usblp->present)
 901                 return -ENODEV;
 902         if (signal_pending(current))
 903                 return -EINTR;
 904         spin_lock_irqsave(&usblp->lock, flags);
 905         if (usblp->wcomplete) {
 906                 spin_unlock_irqrestore(&usblp->lock, flags);
 907                 return 0;
 908         }
 909         spin_unlock_irqrestore(&usblp->lock, flags);
 910         if (nonblock)
 911                 return -EAGAIN;
 912         return 1;
 913 }
 914
 915 /*
 916  * Wait for read bytes to become available. This probably should have been
 917  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 918  * name for functions which lock and return.
 919  *
 920  * We do not use wait_event_interruptible because it makes locking iffy.
 921  */
 922 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 923 {
 924         DECLARE_WAITQUEUE(waita, current);
 925         int rc;
 926
 927         add_wait_queue(&usblp->rwait, &waita);
 928         for (;;) {
 929                 if (mutex_lock_interruptible(&usblp->mut)) {
 930                         rc = -EINTR;
 931                         break;
 932                 }
 933                 set_current_state(TASK_INTERRUPTIBLE);
 934                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 935                         mutex_unlock(&usblp->mut);
 936                         break;
 937                 }
 938                 if (rc == 0)    /* Keep it locked */
 939                         break;
 940                 mutex_unlock(&usblp->mut);
 941                 schedule();
 942         }
 943         set_current_state(TASK_RUNNING);
 944         remove_wait_queue(&usblp->rwait, &waita);
 945         return rc;
 946 }
 947
 948 static int usblp_rtest(struct usblp *usblp, int nonblock)
 949 {
 950         unsigned long flags;
 951
 952         if (!usblp->present)
 953                 return -ENODEV;
 954         if (signal_pending(current))
 955                 return -EINTR;
 956         spin_lock_irqsave(&usblp->lock, flags);
 957         if (usblp->rcomplete) {
 958                 spin_unlock_irqrestore(&usblp->lock, flags);
 959                 return 0;
 960         }
 961         spin_unlock_irqrestore(&usblp->lock, flags);
 962         if (nonblock)
 963                 return -EAGAIN;
 964         return 1;
 965 }
 966
 967 /*
 968  * Please check ->bidir and other such things outside for now.
 969  */
 970 static int usblp_submit_read(struct usblp *usblp)
 971 {
 972         struct urb *urb;
 973         unsigned long flags;
 974         int rc;
 975
 976         rc = -ENOMEM;
 977         if ((urb = usb_alloc_urb(0, GFP_KERNEL)) == NULL)
 978                 goto raise_urb;
 979
 980         usb_fill_bulk_urb(urb, usblp->dev,
 981                 usb_rcvbulkpipe(usblp->dev,
 982                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
 983                 usblp->readbuf, USBLP_BUF_SIZE_IN,
 984                 usblp_bulk_read, usblp);
 985         usb_anchor_urb(urb, &usblp->urbs);
 986
 987         spin_lock_irqsave(&usblp->lock, flags);
 988         usblp->readcount = 0; /* XXX Why here? */
 989         usblp->rcomplete = 0;
 990         spin_unlock_irqrestore(&usblp->lock, flags);
 991         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
 992                 dbg("error submitting urb (%d)", rc);
 993                 spin_lock_irqsave(&usblp->lock, flags);
 994                 usblp->rstatus = rc;
 995                 usblp->rcomplete = 1;
 996                 spin_unlock_irqrestore(&usblp->lock, flags);
 997                 goto raise_submit;
 998         }
 999
1000         return 0;
1001
1002 raise_submit:
1003         usb_unanchor_urb(urb);
1004         usb_free_urb(urb);
1005 raise_urb:
1006         return rc;
1007 }
1008
1009 /*
1010  * Checks for printers that have quirks, such as requiring unidirectional
1011  * communication but reporting bidirectional; currently some HP printers
1012  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1013  * sent at each open (like some Epsons).
1014  * Returns 1 if found, 0 if not found.
1015  *
1016  * HP recommended that we use the bidirectional interface but
1017  * don't attempt any bulk IN transfers from the IN endpoint.
1018  * Here's some more detail on the problem:
1019  * The problem is not that it isn't bidirectional though. The problem
1020  * is that if you request a device ID, or status information, while
1021  * the buffers are full, the return data will end up in the print data
1022  * buffer. For example if you make sure you never request the device ID
1023  * while you are sending print data, and you don't try to query the
1024  * printer status every couple of milliseconds, you will probably be OK.
1025  */
1026 static unsigned int usblp_quirks (__u16 vendor, __u16 product)
1027 {
1028         int i;
1029
1030         for (i = 0; quirk_printers[i].vendorId; i++) {
1031                 if (vendor == quirk_printers[i].vendorId &&
1032                     product == quirk_printers[i].productId)
1033                         return quirk_printers[i].quirks;
1034         }
1035         return 0;
1036 }
1037
1038 static const struct file_operations usblp_fops = {
1039         .owner =        THIS_MODULE,
1040         .read =         usblp_read,
1041         .write =        usblp_write,
1042         .poll =         usblp_poll,
1043         .unlocked_ioctl =       usblp_ioctl,
1044         .compat_ioctl =         usblp_ioctl,
1045         .open =         usblp_open,
1046         .release =      usblp_release,
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");