drivers/usb/class/usblp.c

   1 /*
   2  * usblp.c
   3  *
   4  * Copyright (c) 1999 Michael Gee       <[email protected]>
   5  * Copyright (c) 1999 Pavel Machek      <[email protected]>
   6  * Copyright (c) 2000 Randy Dunlap      <[email protected]>
   7  * Copyright (c) 2000 Vojtech Pavlik    <[email protected]>
   8  # Copyright (c) 2001 Pete Zaitcev      <[email protected]>
   9  # Copyright (c) 2001 David Paschal     <[email protected]>
  10  * Copyright (c) 2006 Oliver Neukum     <[email protected]>
  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 ([email protected])
  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/slab.h>
  56 #include <linux/lp.h>
  57 #include <linux/mutex.h>
  58 #undef DEBUG
  59 #include <linux/usb.h>
  60 #include <linux/usb/ch9.h>
  61 #include <linux/ratelimit.h>
  62
  63 /*
  64  * Version Information
  65  */
  66 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  67 #define DRIVER_DESC "USB Printer Device Class driver"
  68
  69 #define USBLP_BUF_SIZE          8192
  70 #define USBLP_BUF_SIZE_IN       1024
  71 #define USBLP_DEVICE_ID_SIZE    1024
  72
  73 /* ioctls: */
  74 #define IOCNR_GET_DEVICE_ID             1
  75 #define IOCNR_GET_PROTOCOLS             2
  76 #define IOCNR_SET_PROTOCOL              3
  77 #define IOCNR_HP_SET_CHANNEL            4
  78 #define IOCNR_GET_BUS_ADDRESS           5
  79 #define IOCNR_GET_VID_PID               6
  80 #define IOCNR_SOFT_RESET                7
  81 /* Get device_id string: */
  82 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  83 /* The following ioctls were added for http://hpoj.sourceforge.net:
  84  * Get two-int array:
  85  * [0]=current protocol
  86  *     (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  87  *         3=USB_CLASS_PRINTER/1/3),
  88  * [1]=supported protocol mask (mask&(1<<n)!=0 means
  89  *     USB_CLASS_PRINTER/1/n supported):
  90  */
  91 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  92 /*
  93  * Set protocol
  94  *     (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  95  *         3=USB_CLASS_PRINTER/1/3):
  96  */
  97 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  98 /* Set channel number (HP Vendor-specific command): */
  99 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
 100 /* Get two-int array: [0]=bus number, [1]=device address: */
 101 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
 102 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
 103 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
 104 /* Perform class specific soft reset */
 105 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
 106
 107 /*
 108  * A DEVICE_ID string may include the printer's serial number.
 109  * It should end with a semi-colon (';').
 110  * An example from an HP 970C DeskJet printer is (this is one long string,
 111  * with the serial number changed):
 112 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:                    ;
 113  */
 114
 115 /*
 116  * USB Printer Requests
 117  */
 118
 119 #define USBLP_REQ_GET_ID                        0x00
 120 #define USBLP_REQ_GET_STATUS                    0x01
 121 #define USBLP_REQ_RESET                         0x02
 122 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
 123
 124 #define USBLP_MINORS            16
 125 #define USBLP_MINOR_BASE        0
 126
 127 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
 128
 129 #define USBLP_FIRST_PROTOCOL    1
 130 #define USBLP_LAST_PROTOCOL     3
 131 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
 132
 133 /*
 134  * some arbitrary status buffer size;
 135  * need a status buffer that is allocated via kmalloc(), not on stack
 136  */
 137 #define STATUS_BUF_SIZE         8
 138
 139 /*
 140  * Locks down the locking order:
 141  * ->wmut locks wstatus.
 142  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 143  * [rw]status. We only touch status when we know the side idle.
 144  * ->lock locks what interrupt accesses.
 145  */
 146 struct usblp {
 147         struct usb_device       *dev;                   /* USB device */
 148         struct mutex            wmut;
 149         struct mutex            mut;
 150         spinlock_t              lock;           /* locks rcomplete, wcomplete */
 151         char                    *readbuf;               /* read transfer_buffer */
 152         char                    *statusbuf;             /* status transfer_buffer */
 153         struct usb_anchor       urbs;
 154         wait_queue_head_t       rwait, wwait;
 155         int                     readcount;              /* Counter for reads */
 156         int                     ifnum;                  /* Interface number */
 157         struct usb_interface    *intf;                  /* The interface */
 158         /*
 159          * Alternate-setting numbers and endpoints for each protocol
 160          * (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
 161          */
 162         struct {
 163                 int                             alt_setting;
 164                 struct usb_endpoint_descriptor  *epwrite;
 165                 struct usb_endpoint_descriptor  *epread;
 166         }                       protocol[USBLP_MAX_PROTOCOLS];
 167         int                     current_protocol;
 168         int                     minor;                  /* minor number of device */
 169         int                     wcomplete, rcomplete;
 170         int                     wstatus;        /* bytes written or error */
 171         int                     rstatus;        /* bytes ready or error */
 172         unsigned int            quirks;                 /* quirks flags */
 173         unsigned int            flags;                  /* mode flags */
 174         unsigned char           used;                   /* True if open */
 175         unsigned char           present;                /* True if not disconnected */
 176         unsigned char           bidir;                  /* interface is bidirectional */
 177         unsigned char           no_paper;               /* Paper Out happened */
 178         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 179                                                         /* first 2 bytes are (big-endian) length */
 180 };
 181
 182 #ifdef DEBUG
 183 static void usblp_dump(struct usblp *usblp)
 184 {
 185         struct device *dev = &usblp->intf->dev;
 186         int p;
 187
 188         dev_dbg(dev, "usblp=0x%p\n", usblp);
 189         dev_dbg(dev, "dev=0x%p\n", usblp->dev);
 190         dev_dbg(dev, "present=%d\n", usblp->present);
 191         dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
 192         dev_dbg(dev, "readcount=%d\n", usblp->readcount);
 193         dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
 194         for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 195                 dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
 196                         usblp->protocol[p].alt_setting);
 197                 dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
 198                         usblp->protocol[p].epwrite);
 199                 dev_dbg(dev, "protocol[%d].epread=%p\n", p,
 200                         usblp->protocol[p].epread);
 201         }
 202         dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
 203         dev_dbg(dev, "minor=%d\n", usblp->minor);
 204         dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
 205         dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
 206         dev_dbg(dev, "quirks=%d\n", usblp->quirks);
 207         dev_dbg(dev, "used=%d\n", usblp->used);
 208         dev_dbg(dev, "bidir=%d\n", usblp->bidir);
 209         dev_dbg(dev, "device_id_string=\"%s\"\n",
 210                 usblp->device_id_string ?
 211                         usblp->device_id_string + 2 :
 212                         (unsigned char *)"(null)");
 213 }
 214 #endif
 215
 216 /* Quirks: various printer quirks are handled by this table & its flags. */
 217
 218 struct quirk_printer_struct {
 219         __u16 vendorId;
 220         __u16 productId;
 221         unsigned int quirks;
 222 };
 223
 224 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 225 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 226 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
 227
 228 static const struct quirk_printer_struct quirk_printers[] = {
 229         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 230         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 231         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 232         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 233         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 234         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 235         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 236         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 237         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 238         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 239         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 240         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 241         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 242         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <[email protected]> */
 243         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 244         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
 245         { 0, 0 }
 246 };
 247
 248 static int usblp_wwait(struct usblp *usblp, int nonblock);
 249 static int usblp_wtest(struct usblp *usblp, int nonblock);
 250 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
 251 static int usblp_rtest(struct usblp *usblp, int nonblock);
 252 static int usblp_submit_read(struct usblp *usblp);
 253 static int usblp_select_alts(struct usblp *usblp);
 254 static int usblp_set_protocol(struct usblp *usblp, int protocol);
 255 static int usblp_cache_device_id_string(struct usblp *usblp);
 256
 257 /* forward reference to make our lives easier */
 258 static struct usb_driver usblp_driver;
 259 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
 260
 261 /*
 262  * Functions for usblp control messages.
 263  */
 264
 265 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 266 {
 267         int retval;
 268         int index = usblp->ifnum;
 269
 270         /* High byte has the interface index.
 271            Low byte has the alternate setting.
 272          */
 273         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
 274                 index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 275
 276         retval = usb_control_msg(usblp->dev,
 277                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 278                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
 279         dev_dbg(&usblp->intf->dev,
 280                 "usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
 281                 request, !!dir, recip, value, index, len, retval);
 282         return retval < 0 ? retval : 0;
 283 }
 284
 285 #define usblp_read_status(usblp, status)\
 286         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 287 #define usblp_get_id(usblp, config, id, maxlen)\
 288         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 289 #define usblp_reset(usblp)\
 290         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 291
 292 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
 293         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
 294
 295 /*
 296  * See the description for usblp_select_alts() below for the usage
 297  * explanation.  Look into your /proc/bus/usb/devices and dmesg in
 298  * case of any trouble.
 299  */
 300 static int proto_bias = -1;
 301
 302 /*
 303  * URB callback.
 304  */
 305
 306 static void usblp_bulk_read(struct urb *urb)
 307 {
 308         struct usblp *usblp = urb->context;
 309         int status = urb->status;
 310
 311         if (usblp->present && usblp->used) {
 312                 if (status)
 313                         printk(KERN_WARNING "usblp%d: "
 314                             "nonzero read bulk status received: %d\n",
 315                             usblp->minor, status);
 316         }
 317         spin_lock(&usblp->lock);
 318         if (status < 0)
 319                 usblp->rstatus = status;
 320         else
 321                 usblp->rstatus = urb->actual_length;
 322         usblp->rcomplete = 1;
 323         wake_up(&usblp->rwait);
 324         spin_unlock(&usblp->lock);
 325
 326         usb_free_urb(urb);
 327 }
 328
 329 static void usblp_bulk_write(struct urb *urb)
 330 {
 331         struct usblp *usblp = urb->context;
 332         int status = urb->status;
 333
 334         if (usblp->present && usblp->used) {
 335                 if (status)
 336                         printk(KERN_WARNING "usblp%d: "
 337                             "nonzero write bulk status received: %d\n",
 338                             usblp->minor, status);
 339         }
 340         spin_lock(&usblp->lock);
 341         if (status < 0)
 342                 usblp->wstatus = status;
 343         else
 344                 usblp->wstatus = urb->actual_length;
 345         usblp->no_paper = 0;
 346         usblp->wcomplete = 1;
 347         wake_up(&usblp->wwait);
 348         spin_unlock(&usblp->lock);
 349
 350         usb_free_urb(urb);
 351 }
 352
 353 /*
 354  * Get and print printer errors.
 355  */
 356
 357 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 358
 359 static int usblp_check_status(struct usblp *usblp, int err)
 360 {
 361         unsigned char status, newerr = 0;
 362         int error;
 363
 364         mutex_lock(&usblp->mut);
 365         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 366                 mutex_unlock(&usblp->mut);
 367                 printk_ratelimited(KERN_ERR
 368                                 "usblp%d: error %d reading printer status\n",
 369                                 usblp->minor, error);
 370                 return 0;
 371         }
 372         status = *usblp->statusbuf;
 373         mutex_unlock(&usblp->mut);
 374
 375         if (~status & LP_PERRORP)
 376                 newerr = 3;
 377         if (status & LP_POUTPA)
 378                 newerr = 1;
 379         if (~status & LP_PSELECD)
 380                 newerr = 2;
 381
 382         if (newerr != err) {
 383                 printk(KERN_INFO "usblp%d: %s\n",
 384                    usblp->minor, usblp_messages[newerr]);
 385         }
 386
 387         return newerr;
 388 }
 389
 390 static int handle_bidir(struct usblp *usblp)
 391 {
 392         if (usblp->bidir && usblp->used) {
 393                 if (usblp_submit_read(usblp) < 0)
 394                         return -EIO;
 395         }
 396         return 0;
 397 }
 398
 399 /*
 400  * File op functions.
 401  */
 402
 403 static int usblp_open(struct inode *inode, struct file *file)
 404 {
 405         int minor = iminor(inode);
 406         struct usblp *usblp;
 407         struct usb_interface *intf;
 408         int retval;
 409
 410         if (minor < 0)
 411                 return -ENODEV;
 412
 413         mutex_lock(&usblp_mutex);
 414
 415         retval = -ENODEV;
 416         intf = usb_find_interface(&usblp_driver, minor);
 417         if (!intf)
 418                 goto out;
 419         usblp = usb_get_intfdata(intf);
 420         if (!usblp || !usblp->dev || !usblp->present)
 421                 goto out;
 422
 423         retval = -EBUSY;
 424         if (usblp->used)
 425                 goto out;
 426
 427         /*
 428          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 429          *  - We do not want persistent state which close(2) does not clear
 430          *  - It is not used anyway, according to CUPS people
 431          */
 432
 433         retval = usb_autopm_get_interface(intf);
 434         if (retval < 0)
 435                 goto out;
 436         usblp->used = 1;
 437         file->private_data = usblp;
 438
 439         usblp->wcomplete = 1; /* we begin writeable */
 440         usblp->wstatus = 0;
 441         usblp->rcomplete = 0;
 442
 443         if (handle_bidir(usblp) < 0) {
 444                 usb_autopm_put_interface(intf);
 445                 usblp->used = 0;
 446                 file->private_data = NULL;
 447                 retval = -EIO;
 448         }
 449 out:
 450         mutex_unlock(&usblp_mutex);
 451         return retval;
 452 }
 453
 454 static void usblp_cleanup(struct usblp *usblp)
 455 {
 456         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 457
 458         kfree(usblp->readbuf);
 459         kfree(usblp->device_id_string);
 460         kfree(usblp->statusbuf);
 461         kfree(usblp);
 462 }
 463
 464 static void usblp_unlink_urbs(struct usblp *usblp)
 465 {
 466         usb_kill_anchored_urbs(&usblp->urbs);
 467 }
 468
 469 static int usblp_release(struct inode *inode, struct file *file)
 470 {
 471         struct usblp *usblp = file->private_data;
 472
 473         usblp->flags &= ~LP_ABORT;
 474
 475         mutex_lock(&usblp_mutex);
 476         usblp->used = 0;
 477         if (usblp->present) {
 478                 usblp_unlink_urbs(usblp);
 479                 usb_autopm_put_interface(usblp->intf);
 480         } else          /* finish cleanup from disconnect */
 481                 usblp_cleanup(usblp);
 482         mutex_unlock(&usblp_mutex);
 483         return 0;
 484 }
 485
 486 /* No kernel lock - fine */
 487 static unsigned int usblp_poll(struct file *file, struct poll_table_struct *wait)
 488 {
 489         int ret;
 490         unsigned long flags;
 491
 492         struct usblp *usblp = file->private_data;
 493         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 494         poll_wait(file, &usblp->rwait, wait);
 495         poll_wait(file, &usblp->wwait, wait);
 496         spin_lock_irqsave(&usblp->lock, flags);
 497         ret = ((usblp->bidir && usblp->rcomplete) ? POLLIN  | POLLRDNORM : 0) |
 498            ((usblp->no_paper || usblp->wcomplete) ? POLLOUT | POLLWRNORM : 0);
 499         spin_unlock_irqrestore(&usblp->lock, flags);
 500         return ret;
 501 }
 502
 503 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 504 {
 505         struct usblp *usblp = file->private_data;
 506         int length, err, i;
 507         unsigned char newChannel;
 508         int status;
 509         int twoints[2];
 510         int retval = 0;
 511
 512         mutex_lock(&usblp->mut);
 513         if (!usblp->present) {
 514                 retval = -ENODEV;
 515                 goto done;
 516         }
 517
 518         dev_dbg(&usblp->intf->dev,
 519                 "usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
 520                 _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 521
 522         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 523
 524                 switch (_IOC_NR(cmd)) {
 525
 526                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 527                         if (_IOC_DIR(cmd) != _IOC_READ) {
 528                                 retval = -EINVAL;
 529                                 goto done;
 530                         }
 531
 532                         length = usblp_cache_device_id_string(usblp);
 533                         if (length < 0) {
 534                                 retval = length;
 535                                 goto done;
 536                         }
 537                         if (length > _IOC_SIZE(cmd))
 538                                 length = _IOC_SIZE(cmd); /* truncate */
 539
 540                         if (copy_to_user((void __user *) arg,
 541                                         usblp->device_id_string,
 542                                         (unsigned long) length)) {
 543                                 retval = -EFAULT;
 544                                 goto done;
 545                         }
 546
 547                         break;
 548
 549                 case IOCNR_GET_PROTOCOLS:
 550                         if (_IOC_DIR(cmd) != _IOC_READ ||
 551                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 552                                 retval = -EINVAL;
 553                                 goto done;
 554                         }
 555
 556                         twoints[0] = usblp->current_protocol;
 557                         twoints[1] = 0;
 558                         for (i = USBLP_FIRST_PROTOCOL;
 559                              i <= USBLP_LAST_PROTOCOL; i++) {
 560                                 if (usblp->protocol[i].alt_setting >= 0)
 561                                         twoints[1] |= (1<<i);
 562                         }
 563
 564                         if (copy_to_user((void __user *)arg,
 565                                         (unsigned char *)twoints,
 566                                         sizeof(twoints))) {
 567                                 retval = -EFAULT;
 568                                 goto done;
 569                         }
 570
 571                         break;
 572
 573                 case IOCNR_SET_PROTOCOL:
 574                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
 575                                 retval = -EINVAL;
 576                                 goto done;
 577                         }
 578
 579 #ifdef DEBUG
 580                         if (arg == -10) {
 581                                 usblp_dump(usblp);
 582                                 break;
 583                         }
 584 #endif
 585
 586                         usblp_unlink_urbs(usblp);
 587                         retval = usblp_set_protocol(usblp, arg);
 588                         if (retval < 0) {
 589                                 usblp_set_protocol(usblp,
 590                                         usblp->current_protocol);
 591                         }
 592                         break;
 593
 594                 case IOCNR_HP_SET_CHANNEL:
 595                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
 596                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 597                             usblp->quirks & USBLP_QUIRK_BIDIR) {
 598                                 retval = -EINVAL;
 599                                 goto done;
 600                         }
 601
 602                         err = usblp_hp_channel_change_request(usblp,
 603                                 arg, &newChannel);
 604                         if (err < 0) {
 605                                 dev_err(&usblp->dev->dev,
 606                                         "usblp%d: error = %d setting "
 607                                         "HP channel\n",
 608                                         usblp->minor, err);
 609                                 retval = -EIO;
 610                                 goto done;
 611                         }
 612
 613                         dev_dbg(&usblp->intf->dev,
 614                                 "usblp%d requested/got HP channel %ld/%d\n",
 615                                 usblp->minor, arg, newChannel);
 616                         break;
 617
 618                 case IOCNR_GET_BUS_ADDRESS:
 619                         if (_IOC_DIR(cmd) != _IOC_READ ||
 620                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 621                                 retval = -EINVAL;
 622                                 goto done;
 623                         }
 624
 625                         twoints[0] = usblp->dev->bus->busnum;
 626                         twoints[1] = usblp->dev->devnum;
 627                         if (copy_to_user((void __user *)arg,
 628                                         (unsigned char *)twoints,
 629                                         sizeof(twoints))) {
 630                                 retval = -EFAULT;
 631                                 goto done;
 632                         }
 633
 634                         dev_dbg(&usblp->intf->dev,
 635                                 "usblp%d is bus=%d, device=%d\n",
 636                                 usblp->minor, twoints[0], twoints[1]);
 637                         break;
 638
 639                 case IOCNR_GET_VID_PID:
 640                         if (_IOC_DIR(cmd) != _IOC_READ ||
 641                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 642                                 retval = -EINVAL;
 643                                 goto done;
 644                         }
 645
 646                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 647                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 648                         if (copy_to_user((void __user *)arg,
 649                                         (unsigned char *)twoints,
 650                                         sizeof(twoints))) {
 651                                 retval = -EFAULT;
 652                                 goto done;
 653                         }
 654
 655                         dev_dbg(&usblp->intf->dev,
 656                                 "usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
 657                                 usblp->minor, twoints[0], twoints[1]);
 658                         break;
 659
 660                 case IOCNR_SOFT_RESET:
 661                         if (_IOC_DIR(cmd) != _IOC_NONE) {
 662                                 retval = -EINVAL;
 663                                 goto done;
 664                         }
 665                         retval = usblp_reset(usblp);
 666                         break;
 667                 default:
 668                         retval = -ENOTTY;
 669                 }
 670         else    /* old-style ioctl value */
 671                 switch (cmd) {
 672
 673                 case LPGETSTATUS:
 674                         retval = usblp_read_status(usblp, usblp->statusbuf);
 675                         if (retval) {
 676                                 printk_ratelimited(KERN_ERR "usblp%d:"
 677                                             "failed reading printer status (%d)\n",
 678                                             usblp->minor, retval);
 679                                 retval = -EIO;
 680                                 goto done;
 681                         }
 682                         status = *usblp->statusbuf;
 683                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 684                                 retval = -EFAULT;
 685                         break;
 686
 687                 case LPABORT:
 688                         if (arg)
 689                                 usblp->flags |= LP_ABORT;
 690                         else
 691                                 usblp->flags &= ~LP_ABORT;
 692                         break;
 693
 694                 default:
 695                         retval = -ENOTTY;
 696                 }
 697
 698 done:
 699         mutex_unlock(&usblp->mut);
 700         return retval;
 701 }
 702
 703 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 704 {
 705         struct urb *urb;
 706         char *writebuf;
 707
 708         writebuf = kmalloc(transfer_length, GFP_KERNEL);
 709         if (writebuf == NULL)
 710                 return NULL;
 711         urb = usb_alloc_urb(0, GFP_KERNEL);
 712         if (urb == NULL) {
 713                 kfree(writebuf);
 714                 return NULL;
 715         }
 716
 717         usb_fill_bulk_urb(urb, usblp->dev,
 718                 usb_sndbulkpipe(usblp->dev,
 719                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 720                 writebuf, transfer_length, usblp_bulk_write, usblp);
 721         urb->transfer_flags |= URB_FREE_BUFFER;
 722
 723         return urb;
 724 }
 725
 726 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 727 {
 728         struct usblp *usblp = file->private_data;
 729         struct urb *writeurb;
 730         int rv;
 731         int transfer_length;
 732         ssize_t writecount = 0;
 733
 734         if (mutex_lock_interruptible(&usblp->wmut)) {
 735                 rv = -EINTR;
 736                 goto raise_biglock;
 737         }
 738         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 739                 goto raise_wait;
 740
 741         while (writecount < count) {
 742                 /*
 743                  * Step 1: Submit next block.
 744                  */
 745                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 746                         transfer_length = USBLP_BUF_SIZE;
 747
 748                 rv = -ENOMEM;
 749                 writeurb = usblp_new_writeurb(usblp, transfer_length);
 750                 if (writeurb == NULL)
 751                         goto raise_urb;
 752                 usb_anchor_urb(writeurb, &usblp->urbs);
 753
 754                 if (copy_from_user(writeurb->transfer_buffer,
 755                                    buffer + writecount, transfer_length)) {
 756                         rv = -EFAULT;
 757                         goto raise_badaddr;
 758                 }
 759
 760                 spin_lock_irq(&usblp->lock);
 761                 usblp->wcomplete = 0;
 762                 spin_unlock_irq(&usblp->lock);
 763                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 764                         usblp->wstatus = 0;
 765                         spin_lock_irq(&usblp->lock);
 766                         usblp->no_paper = 0;
 767                         usblp->wcomplete = 1;
 768                         wake_up(&usblp->wwait);
 769                         spin_unlock_irq(&usblp->lock);
 770                         if (rv != -ENOMEM)
 771                                 rv = -EIO;
 772                         goto raise_submit;
 773                 }
 774
 775                 /*
 776                  * Step 2: Wait for transfer to end, collect results.
 777                  */
 778                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 779                 if (rv < 0) {
 780                         if (rv == -EAGAIN) {
 781                                 /* Presume that it's going to complete well. */
 782                                 writecount += transfer_length;
 783                         }
 784                         if (rv == -ENOSPC) {
 785                                 spin_lock_irq(&usblp->lock);
 786                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 787                                 spin_unlock_irq(&usblp->lock);
 788                                 writecount += transfer_length;
 789                         }
 790                         /* Leave URB dangling, to be cleaned on close. */
 791                         goto collect_error;
 792                 }
 793
 794                 if (usblp->wstatus < 0) {
 795                         rv = -EIO;
 796                         goto collect_error;
 797                 }
 798                 /*
 799                  * This is critical: it must be our URB, not other writer's.
 800                  * The wmut exists mainly to cover us here.
 801                  */
 802                 writecount += usblp->wstatus;
 803         }
 804
 805         mutex_unlock(&usblp->wmut);
 806         return writecount;
 807
 808 raise_submit:
 809 raise_badaddr:
 810         usb_unanchor_urb(writeurb);
 811         usb_free_urb(writeurb);
 812 raise_urb:
 813 raise_wait:
 814 collect_error:          /* Out of raise sequence */
 815         mutex_unlock(&usblp->wmut);
 816 raise_biglock:
 817         return writecount ? writecount : rv;
 818 }
 819
 820 /*
 821  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 822  * error, etc. This is the historical behaviour. In all such cases we return
 823  * EIO, and applications loop in order to get the new read going.
 824  */
 825 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 826 {
 827         struct usblp *usblp = file->private_data;
 828         ssize_t count;
 829         ssize_t avail;
 830         int rv;
 831
 832         if (!usblp->bidir)
 833                 return -EINVAL;
 834
 835         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 836         if (rv < 0)
 837                 return rv;
 838
 839         if ((avail = usblp->rstatus) < 0) {
 840                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 841                     usblp->minor, (int)avail);
 842                 usblp_submit_read(usblp);
 843                 count = -EIO;
 844                 goto done;
 845         }
 846
 847         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 848         if (count != 0 &&
 849             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 850                 count = -EFAULT;
 851                 goto done;
 852         }
 853
 854         if ((usblp->readcount += count) == avail) {
 855                 if (usblp_submit_read(usblp) < 0) {
 856                         /* We don't want to leak USB return codes into errno. */
 857                         if (count == 0)
 858                                 count = -EIO;
 859                         goto done;
 860                 }
 861         }
 862
 863 done:
 864         mutex_unlock(&usblp->mut);
 865         return count;
 866 }
 867
 868 /*
 869  * Wait for the write path to come idle.
 870  * This is called under the ->wmut, so the idle path stays idle.
 871  *
 872  * Our write path has a peculiar property: it does not buffer like a tty,
 873  * but waits for the write to succeed. This allows our ->release to bug out
 874  * without waiting for writes to drain. But it obviously does not work
 875  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 876  * select(2) or poll(2) to wait for the buffer to drain before closing.
 877  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 878  */
 879 static int usblp_wwait(struct usblp *usblp, int nonblock)
 880 {
 881         DECLARE_WAITQUEUE(waita, current);
 882         int rc;
 883         int err = 0;
 884
 885         add_wait_queue(&usblp->wwait, &waita);
 886         for (;;) {
 887                 if (mutex_lock_interruptible(&usblp->mut)) {
 888                         rc = -EINTR;
 889                         break;
 890                 }
 891                 set_current_state(TASK_INTERRUPTIBLE);
 892                 rc = usblp_wtest(usblp, nonblock);
 893                 mutex_unlock(&usblp->mut);
 894                 if (rc <= 0)
 895                         break;
 896
 897                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 898                         if (usblp->flags & LP_ABORT) {
 899                                 err = usblp_check_status(usblp, err);
 900                                 if (err == 1) { /* Paper out */
 901                                         rc = -ENOSPC;
 902                                         break;
 903                                 }
 904                         } else {
 905                                 /* Prod the printer, Gentoo#251237. */
 906                                 mutex_lock(&usblp->mut);
 907                                 usblp_read_status(usblp, usblp->statusbuf);
 908                                 mutex_unlock(&usblp->mut);
 909                         }
 910                 }
 911         }
 912         set_current_state(TASK_RUNNING);
 913         remove_wait_queue(&usblp->wwait, &waita);
 914         return rc;
 915 }
 916
 917 static int usblp_wtest(struct usblp *usblp, int nonblock)
 918 {
 919         unsigned long flags;
 920
 921         if (!usblp->present)
 922                 return -ENODEV;
 923         if (signal_pending(current))
 924                 return -EINTR;
 925         spin_lock_irqsave(&usblp->lock, flags);
 926         if (usblp->wcomplete) {
 927                 spin_unlock_irqrestore(&usblp->lock, flags);
 928                 return 0;
 929         }
 930         spin_unlock_irqrestore(&usblp->lock, flags);
 931         if (nonblock)
 932                 return -EAGAIN;
 933         return 1;
 934 }
 935
 936 /*
 937  * Wait for read bytes to become available. This probably should have been
 938  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 939  * name for functions which lock and return.
 940  *
 941  * We do not use wait_event_interruptible because it makes locking iffy.
 942  */
 943 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 944 {
 945         DECLARE_WAITQUEUE(waita, current);
 946         int rc;
 947
 948         add_wait_queue(&usblp->rwait, &waita);
 949         for (;;) {
 950                 if (mutex_lock_interruptible(&usblp->mut)) {
 951                         rc = -EINTR;
 952                         break;
 953                 }
 954                 set_current_state(TASK_INTERRUPTIBLE);
 955                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 956                         mutex_unlock(&usblp->mut);
 957                         break;
 958                 }
 959                 if (rc == 0)    /* Keep it locked */
 960                         break;
 961                 mutex_unlock(&usblp->mut);
 962                 schedule();
 963         }
 964         set_current_state(TASK_RUNNING);
 965         remove_wait_queue(&usblp->rwait, &waita);
 966         return rc;
 967 }
 968
 969 static int usblp_rtest(struct usblp *usblp, int nonblock)
 970 {
 971         unsigned long flags;
 972
 973         if (!usblp->present)
 974                 return -ENODEV;
 975         if (signal_pending(current))
 976                 return -EINTR;
 977         spin_lock_irqsave(&usblp->lock, flags);
 978         if (usblp->rcomplete) {
 979                 spin_unlock_irqrestore(&usblp->lock, flags);
 980                 return 0;
 981         }
 982         spin_unlock_irqrestore(&usblp->lock, flags);
 983         if (nonblock)
 984                 return -EAGAIN;
 985         return 1;
 986 }
 987
 988 /*
 989  * Please check ->bidir and other such things outside for now.
 990  */
 991 static int usblp_submit_read(struct usblp *usblp)
 992 {
 993         struct urb *urb;
 994         unsigned long flags;
 995         int rc;
 996
 997         rc = -ENOMEM;
 998         urb = usb_alloc_urb(0, GFP_KERNEL);
 999         if (urb == NULL)
1000                 goto raise_urb;
1001
1002         usb_fill_bulk_urb(urb, usblp->dev,
1003                 usb_rcvbulkpipe(usblp->dev,
1004                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
1005                 usblp->readbuf, USBLP_BUF_SIZE_IN,
1006                 usblp_bulk_read, usblp);
1007         usb_anchor_urb(urb, &usblp->urbs);
1008
1009         spin_lock_irqsave(&usblp->lock, flags);
1010         usblp->readcount = 0; /* XXX Why here? */
1011         usblp->rcomplete = 0;
1012         spin_unlock_irqrestore(&usblp->lock, flags);
1013         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1014                 dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1015                 spin_lock_irqsave(&usblp->lock, flags);
1016                 usblp->rstatus = rc;
1017                 usblp->rcomplete = 1;
1018                 spin_unlock_irqrestore(&usblp->lock, flags);
1019                 goto raise_submit;
1020         }
1021
1022         return 0;
1023
1024 raise_submit:
1025         usb_unanchor_urb(urb);
1026         usb_free_urb(urb);
1027 raise_urb:
1028         return rc;
1029 }
1030
1031 /*
1032  * Checks for printers that have quirks, such as requiring unidirectional
1033  * communication but reporting bidirectional; currently some HP printers
1034  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1035  * sent at each open (like some Epsons).
1036  * Returns 1 if found, 0 if not found.
1037  *
1038  * HP recommended that we use the bidirectional interface but
1039  * don't attempt any bulk IN transfers from the IN endpoint.
1040  * Here's some more detail on the problem:
1041  * The problem is not that it isn't bidirectional though. The problem
1042  * is that if you request a device ID, or status information, while
1043  * the buffers are full, the return data will end up in the print data
1044  * buffer. For example if you make sure you never request the device ID
1045  * while you are sending print data, and you don't try to query the
1046  * printer status every couple of milliseconds, you will probably be OK.
1047  */
1048 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1049 {
1050         int i;
1051
1052         for (i = 0; quirk_printers[i].vendorId; i++) {
1053                 if (vendor == quirk_printers[i].vendorId &&
1054                     product == quirk_printers[i].productId)
1055                         return quirk_printers[i].quirks;
1056         }
1057         return 0;
1058 }
1059
1060 static const struct file_operations usblp_fops = {
1061         .owner =        THIS_MODULE,
1062         .read =         usblp_read,
1063         .write =        usblp_write,
1064         .poll =         usblp_poll,
1065         .unlocked_ioctl =       usblp_ioctl,
1066         .compat_ioctl =         usblp_ioctl,
1067         .open =         usblp_open,
1068         .release =      usblp_release,
1069         .llseek =       noop_llseek,
1070 };
1071
1072 static char *usblp_devnode(struct device *dev, umode_t *mode)
1073 {
1074         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1075 }
1076
1077 static struct usb_class_driver usblp_class = {
1078         .name =         "lp%d",
1079         .devnode =      usblp_devnode,
1080         .fops =         &usblp_fops,
1081         .minor_base =   USBLP_MINOR_BASE,
1082 };
1083
1084 static ssize_t usblp_show_ieee1284_id(struct device *dev, struct device_attribute *attr, char *buf)
1085 {
1086         struct usb_interface *intf = to_usb_interface(dev);
1087         struct usblp *usblp = usb_get_intfdata(intf);
1088
1089         if (usblp->device_id_string[0] == 0 &&
1090             usblp->device_id_string[1] == 0)
1091                 return 0;
1092
1093         return sprintf(buf, "%s", usblp->device_id_string+2);
1094 }
1095
1096 static DEVICE_ATTR(ieee1284_id, S_IRUGO, usblp_show_ieee1284_id, NULL);
1097
1098 static int usblp_probe(struct usb_interface *intf,
1099                        const struct usb_device_id *id)
1100 {
1101         struct usb_device *dev = interface_to_usbdev(intf);
1102         struct usblp *usblp;
1103         int protocol;
1104         int retval;
1105
1106         /* Malloc and start initializing usblp structure so we can use it
1107          * directly. */
1108         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1109         if (!usblp) {
1110                 retval = -ENOMEM;
1111                 goto abort_ret;
1112         }
1113         usblp->dev = dev;
1114         mutex_init(&usblp->wmut);
1115         mutex_init(&usblp->mut);
1116         spin_lock_init(&usblp->lock);
1117         init_waitqueue_head(&usblp->rwait);
1118         init_waitqueue_head(&usblp->wwait);
1119         init_usb_anchor(&usblp->urbs);
1120         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1121         usblp->intf = intf;
1122
1123         /* Malloc device ID string buffer to the largest expected length,
1124          * since we can re-query it on an ioctl and a dynamic string
1125          * could change in length. */
1126         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1127                 retval = -ENOMEM;
1128                 goto abort;
1129         }
1130
1131         /*
1132          * Allocate read buffer. We somewhat wastefully
1133          * malloc both regardless of bidirectionality, because the
1134          * alternate setting can be changed later via an ioctl.
1135          */
1136         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1137                 retval = -ENOMEM;
1138                 goto abort;
1139         }
1140
1141         /* Allocate buffer for printer status */
1142         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1143         if (!usblp->statusbuf) {
1144                 retval = -ENOMEM;
1145                 goto abort;
1146         }
1147
1148         /* Lookup quirks for this printer. */
1149         usblp->quirks = usblp_quirks(
1150                 le16_to_cpu(dev->descriptor.idVendor),
1151                 le16_to_cpu(dev->descriptor.idProduct));
1152
1153         /* Analyze and pick initial alternate settings and endpoints. */
1154         protocol = usblp_select_alts(usblp);
1155         if (protocol < 0) {
1156                 dev_dbg(&intf->dev,
1157                         "incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1158                         le16_to_cpu(dev->descriptor.idVendor),
1159                         le16_to_cpu(dev->descriptor.idProduct));
1160                 retval = -ENODEV;
1161                 goto abort;
1162         }
1163
1164         /* Setup the selected alternate setting and endpoints. */
1165         if (usblp_set_protocol(usblp, protocol) < 0) {
1166                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1167                 goto abort;
1168         }
1169
1170         /* Retrieve and store the device ID string. */
1171         usblp_cache_device_id_string(usblp);
1172         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1173         if (retval)
1174                 goto abort_intfdata;
1175
1176 #ifdef DEBUG
1177         usblp_check_status(usblp, 0);
1178 #endif
1179
1180         usb_set_intfdata(intf, usblp);
1181
1182         usblp->present = 1;
1183
1184         retval = usb_register_dev(intf, &usblp_class);
1185         if (retval) {
1186                 dev_err(&intf->dev,
1187                         "usblp: Not able to get a minor (base %u, slice default): %d\n",
1188                         USBLP_MINOR_BASE, retval);
1189                 goto abort_intfdata;
1190         }
1191         usblp->minor = intf->minor;
1192         dev_info(&intf->dev,
1193                 "usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1194                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1195                 usblp->ifnum,
1196                 usblp->protocol[usblp->current_protocol].alt_setting,
1197                 usblp->current_protocol,
1198                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1199                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1200
1201         return 0;
1202
1203 abort_intfdata:
1204         usb_set_intfdata(intf, NULL);
1205         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1206 abort:
1207         kfree(usblp->readbuf);
1208         kfree(usblp->statusbuf);
1209         kfree(usblp->device_id_string);
1210         kfree(usblp);
1211 abort_ret:
1212         return retval;
1213 }
1214
1215 /*
1216  * We are a "new" style driver with usb_device_id table,
1217  * but our requirements are too intricate for simple match to handle.
1218  *
1219  * The "proto_bias" option may be used to specify the preferred protocol
1220  * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1221  * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1222  * then we bind to it.
1223  *
1224  * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1225  * is compatible with a stream of characters. If we find it, we bind to it.
1226  *
1227  * Note that the people from hpoj.sourceforge.net need to be able to
1228  * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1229  * for this purpose.
1230  *
1231  * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1232  * even though it's probably not stream-compatible, because this matches
1233  * the behaviour of the old code.
1234  *
1235  * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1236  * - the unidirectional interface.
1237  */
1238 static int usblp_select_alts(struct usblp *usblp)
1239 {
1240         struct usb_interface *if_alt;
1241         struct usb_host_interface *ifd;
1242         struct usb_endpoint_descriptor *epd, *epwrite, *epread;
1243         int p, i, e;
1244
1245         if_alt = usblp->intf;
1246
1247         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1248                 usblp->protocol[p].alt_setting = -1;
1249
1250         /* Find out what we have. */
1251         for (i = 0; i < if_alt->num_altsetting; i++) {
1252                 ifd = &if_alt->altsetting[i];
1253
1254                 if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1255                     ifd->desc.bInterfaceSubClass != 1)
1256                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1257                                 continue;
1258
1259                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1260                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1261                         continue;
1262
1263                 /* Look for bulk OUT and IN endpoints. */
1264                 epwrite = epread = NULL;
1265                 for (e = 0; e < ifd->desc.bNumEndpoints; e++) {
1266                         epd = &ifd->endpoint[e].desc;
1267
1268                         if (usb_endpoint_is_bulk_out(epd))
1269                                 if (!epwrite)
1270                                         epwrite = epd;
1271
1272                         if (usb_endpoint_is_bulk_in(epd))
1273                                 if (!epread)
1274                                         epread = epd;
1275                 }
1276
1277                 /* Ignore buggy hardware without the right endpoints. */
1278                 if (!epwrite || (ifd->desc.bInterfaceProtocol > 1 && !epread))
1279                         continue;
1280
1281                 /*
1282                  * Turn off reads for USB_CLASS_PRINTER/1/1 (unidirectional)
1283                  * interfaces and buggy bidirectional printers.
1284                  */
1285                 if (ifd->desc.bInterfaceProtocol == 1) {
1286                         epread = NULL;
1287                 } else if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1288                         printk(KERN_INFO "usblp%d: Disabling reads from "
1289                             "problematic bidirectional printer\n",
1290                             usblp->minor);
1291                         epread = NULL;
1292                 }
1293
1294                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1295                                 ifd->desc.bAlternateSetting;
1296                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1297                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1298         }
1299
1300         /* If our requested protocol is supported, then use it. */
1301         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1302             proto_bias <= USBLP_LAST_PROTOCOL &&
1303             usblp->protocol[proto_bias].alt_setting != -1)
1304                 return proto_bias;
1305
1306         /* Ordering is important here. */
1307         if (usblp->protocol[2].alt_setting != -1)
1308                 return 2;
1309         if (usblp->protocol[1].alt_setting != -1)
1310                 return 1;
1311         if (usblp->protocol[3].alt_setting != -1)
1312                 return 3;
1313
1314         /* If nothing is available, then don't bind to this device. */
1315         return -1;
1316 }
1317
1318 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1319 {
1320         int r, alts;
1321
1322         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1323                 return -EINVAL;
1324
1325         alts = usblp->protocol[protocol].alt_setting;
1326         if (alts < 0)
1327                 return -EINVAL;
1328         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1329         if (r < 0) {
1330                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1331                         alts, usblp->ifnum);
1332                 return r;
1333         }
1334
1335         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1336         usblp->current_protocol = protocol;
1337         dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1338                 usblp->minor, protocol);
1339         return 0;
1340 }
1341
1342 /* Retrieves and caches device ID string.
1343  * Returns length, including length bytes but not null terminator.
1344  * On error, returns a negative errno value. */
1345 static int usblp_cache_device_id_string(struct usblp *usblp)
1346 {
1347         int err, length;
1348
1349         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1350         if (err < 0) {
1351                 dev_dbg(&usblp->intf->dev,
1352                         "usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1353                         usblp->minor, err);
1354                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1355                 return -EIO;
1356         }
1357
1358         /* First two bytes are length in big-endian.
1359          * They count themselves, and we copy them into
1360          * the user's buffer. */
1361         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1362         if (length < 2)
1363                 length = 2;
1364         else if (length >= USBLP_DEVICE_ID_SIZE)
1365                 length = USBLP_DEVICE_ID_SIZE - 1;
1366         usblp->device_id_string[length] = '\0';
1367
1368         dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1369                 usblp->minor, length, &usblp->device_id_string[2]);
1370
1371         return length;
1372 }
1373
1374 static void usblp_disconnect(struct usb_interface *intf)
1375 {
1376         struct usblp *usblp = usb_get_intfdata(intf);
1377
1378         usb_deregister_dev(intf, &usblp_class);
1379
1380         if (!usblp || !usblp->dev) {
1381                 dev_err(&intf->dev, "bogus disconnect\n");
1382                 BUG();
1383         }
1384
1385         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1386
1387         mutex_lock(&usblp_mutex);
1388         mutex_lock(&usblp->mut);
1389         usblp->present = 0;
1390         wake_up(&usblp->wwait);
1391         wake_up(&usblp->rwait);
1392         usb_set_intfdata(intf, NULL);
1393
1394         usblp_unlink_urbs(usblp);
1395         mutex_unlock(&usblp->mut);
1396
1397         if (!usblp->used)
1398                 usblp_cleanup(usblp);
1399         mutex_unlock(&usblp_mutex);
1400 }
1401
1402 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1403 {
1404         struct usblp *usblp = usb_get_intfdata(intf);
1405
1406         usblp_unlink_urbs(usblp);
1407 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1408         /* not strictly necessary, but just in case */
1409         wake_up(&usblp->wwait);
1410         wake_up(&usblp->rwait);
1411 #endif
1412
1413         return 0;
1414 }
1415
1416 static int usblp_resume(struct usb_interface *intf)
1417 {
1418         struct usblp *usblp = usb_get_intfdata(intf);
1419         int r;
1420
1421         r = handle_bidir(usblp);
1422
1423         return r;
1424 }
1425
1426 static const struct usb_device_id usblp_ids[] = {
1427         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1428         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1429         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1430         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1431         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1432         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1433         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1434         { }                                             /* Terminating entry */
1435 };
1436
1437 MODULE_DEVICE_TABLE(usb, usblp_ids);
1438
1439 static struct usb_driver usblp_driver = {
1440         .name =         "usblp",
1441         .probe =        usblp_probe,
1442         .disconnect =   usblp_disconnect,
1443         .suspend =      usblp_suspend,
1444         .resume =       usblp_resume,
1445         .id_table =     usblp_ids,
1446         .supports_autosuspend = 1,
1447 };
1448
1449 module_usb_driver(usblp_driver);
1450
1451 MODULE_AUTHOR(DRIVER_AUTHOR);
1452 MODULE_DESCRIPTION(DRIVER_DESC);
1453 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1454 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1455 MODULE_LICENSE("GPL");