drivers/usb/class/usblp.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * usblp.c
   4  *
   5  * Copyright (c) 1999 Michael Gee       <michael@linuxspecific.com>
   6  * Copyright (c) 1999 Pavel Machek      <pavel@ucw.cz>
   7  * Copyright (c) 2000 Randy Dunlap      <rdunlap@xenotime.net>
   8  * Copyright (c) 2000 Vojtech Pavlik    <vojtech@suse.cz>
   9  # Copyright (c) 2001 Pete Zaitcev      <zaitcev@redhat.com>
  10  # Copyright (c) 2001 David Paschal     <paschal@rcsis.com>
  11  * Copyright (c) 2006 Oliver Neukum     <oliver@neukum.name>
  12  *
  13  * USB Printer Device Class driver for USB printers and printer cables
  14  *
  15  * Sponsored by SuSE
  16  *
  17  * ChangeLog:
  18  *      v0.1 - thorough cleaning, URBification, almost a rewrite
  19  *      v0.2 - some more cleanups
  20  *      v0.3 - cleaner again, waitqueue fixes
  21  *      v0.4 - fixes in unidirectional mode
  22  *      v0.5 - add DEVICE_ID string support
  23  *      v0.6 - never time out
  24  *      v0.7 - fixed bulk-IN read and poll (David Paschal)
  25  *      v0.8 - add devfs support
  26  *      v0.9 - fix unplug-while-open paths
  27  *      v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
  28  *      v0.11 - add proto_bias option (Pete Zaitcev)
  29  *      v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
  30  *      v0.13 - alloc space for statusbuf (<status> not on stack);
  31  *              use usb_alloc_coherent() for read buf & write buf;
  32  *      none  - Maintained in Linux kernel after v0.13
  33  */
  34
  35 #include <linux/module.h>
  36 #include <linux/kernel.h>
  37 #include <linux/sched/signal.h>
  38 #include <linux/signal.h>
  39 #include <linux/poll.h>
  40 #include <linux/slab.h>
  41 #include <linux/lp.h>
  42 #include <linux/mutex.h>
  43 #undef DEBUG
  44 #include <linux/usb.h>
  45 #include <linux/usb/ch9.h>
  46 #include <linux/ratelimit.h>
  47
  48 /*
  49  * Version Information
  50  */
  51 #define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
  52 #define DRIVER_DESC "USB Printer Device Class driver"
  53
  54 #define USBLP_BUF_SIZE          8192
  55 #define USBLP_BUF_SIZE_IN       1024
  56 #define USBLP_DEVICE_ID_SIZE    1024
  57
  58 /* ioctls: */
  59 #define IOCNR_GET_DEVICE_ID             1
  60 #define IOCNR_GET_PROTOCOLS             2
  61 #define IOCNR_SET_PROTOCOL              3
  62 #define IOCNR_HP_SET_CHANNEL            4
  63 #define IOCNR_GET_BUS_ADDRESS           5
  64 #define IOCNR_GET_VID_PID               6
  65 #define IOCNR_SOFT_RESET                7
  66 /* Get device_id string: */
  67 #define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
  68 /* The following ioctls were added for http://hpoj.sourceforge.net:
  69  * Get two-int array:
  70  * [0]=current protocol
  71  *     (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  72  *         3=USB_CLASS_PRINTER/1/3),
  73  * [1]=supported protocol mask (mask&(1<<n)!=0 means
  74  *     USB_CLASS_PRINTER/1/n supported):
  75  */
  76 #define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
  77 /*
  78  * Set protocol
  79  *     (arg: 1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
  80  *         3=USB_CLASS_PRINTER/1/3):
  81  */
  82 #define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
  83 /* Set channel number (HP Vendor-specific command): */
  84 #define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
  85 /* Get two-int array: [0]=bus number, [1]=device address: */
  86 #define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
  87 /* Get two-int array: [0]=vendor ID, [1]=product ID: */
  88 #define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)
  89 /* Perform class specific soft reset */
  90 #define LPIOC_SOFT_RESET _IOC(_IOC_NONE, 'P', IOCNR_SOFT_RESET, 0);
  91
  92 /*
  93  * A DEVICE_ID string may include the printer's serial number.
  94  * It should end with a semi-colon (';').
  95  * An example from an HP 970C DeskJet printer is (this is one long string,
  96  * with the serial number changed):
  97 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:                    ;
  98  */
  99
 100 /*
 101  * USB Printer Requests
 102  */
 103
 104 #define USBLP_REQ_GET_ID                        0x00
 105 #define USBLP_REQ_GET_STATUS                    0x01
 106 #define USBLP_REQ_RESET                         0x02
 107 #define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST     0x00    /* HP Vendor-specific */
 108
 109 #define USBLP_MINORS            16
 110 #define USBLP_MINOR_BASE        0
 111
 112 #define USBLP_CTL_TIMEOUT       5000                    /* 5 seconds */
 113
 114 #define USBLP_FIRST_PROTOCOL    1
 115 #define USBLP_LAST_PROTOCOL     3
 116 #define USBLP_MAX_PROTOCOLS     (USBLP_LAST_PROTOCOL+1)
 117
 118 /*
 119  * some arbitrary status buffer size;
 120  * need a status buffer that is allocated via kmalloc(), not on stack
 121  */
 122 #define STATUS_BUF_SIZE         8
 123
 124 /*
 125  * Locks down the locking order:
 126  * ->wmut locks wstatus.
 127  * ->mut locks the whole usblp, except [rw]complete, and thus, by indirection,
 128  * [rw]status. We only touch status when we know the side idle.
 129  * ->lock locks what interrupt accesses.
 130  */
 131 struct usblp {
 132         struct usb_device       *dev;                   /* USB device */
 133         struct mutex            wmut;
 134         struct mutex            mut;
 135         spinlock_t              lock;           /* locks rcomplete, wcomplete */
 136         char                    *readbuf;               /* read transfer_buffer */
 137         char                    *statusbuf;             /* status transfer_buffer */
 138         struct usb_anchor       urbs;
 139         wait_queue_head_t       rwait, wwait;
 140         int                     readcount;              /* Counter for reads */
 141         int                     ifnum;                  /* Interface number */
 142         struct usb_interface    *intf;                  /* The interface */
 143         /*
 144          * Alternate-setting numbers and endpoints for each protocol
 145          * (USB_CLASS_PRINTER/1/{index=1,2,3}) that the device supports:
 146          */
 147         struct {
 148                 int                             alt_setting;
 149                 struct usb_endpoint_descriptor  *epwrite;
 150                 struct usb_endpoint_descriptor  *epread;
 151         }                       protocol[USBLP_MAX_PROTOCOLS];
 152         int                     current_protocol;
 153         int                     minor;                  /* minor number of device */
 154         int                     wcomplete, rcomplete;
 155         int                     wstatus;        /* bytes written or error */
 156         int                     rstatus;        /* bytes ready or error */
 157         unsigned int            quirks;                 /* quirks flags */
 158         unsigned int            flags;                  /* mode flags */
 159         unsigned char           used;                   /* True if open */
 160         unsigned char           present;                /* True if not disconnected */
 161         unsigned char           bidir;                  /* interface is bidirectional */
 162         unsigned char           no_paper;               /* Paper Out happened */
 163         unsigned char           *device_id_string;      /* IEEE 1284 DEVICE ID string (ptr) */
 164                                                         /* first 2 bytes are (big-endian) length */
 165 };
 166
 167 #ifdef DEBUG
 168 static void usblp_dump(struct usblp *usblp)
 169 {
 170         struct device *dev = &usblp->intf->dev;
 171         int p;
 172
 173         dev_dbg(dev, "usblp=0x%p\n", usblp);
 174         dev_dbg(dev, "dev=0x%p\n", usblp->dev);
 175         dev_dbg(dev, "present=%d\n", usblp->present);
 176         dev_dbg(dev, "readbuf=0x%p\n", usblp->readbuf);
 177         dev_dbg(dev, "readcount=%d\n", usblp->readcount);
 178         dev_dbg(dev, "ifnum=%d\n", usblp->ifnum);
 179         for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
 180                 dev_dbg(dev, "protocol[%d].alt_setting=%d\n", p,
 181                         usblp->protocol[p].alt_setting);
 182                 dev_dbg(dev, "protocol[%d].epwrite=%p\n", p,
 183                         usblp->protocol[p].epwrite);
 184                 dev_dbg(dev, "protocol[%d].epread=%p\n", p,
 185                         usblp->protocol[p].epread);
 186         }
 187         dev_dbg(dev, "current_protocol=%d\n", usblp->current_protocol);
 188         dev_dbg(dev, "minor=%d\n", usblp->minor);
 189         dev_dbg(dev, "wstatus=%d\n", usblp->wstatus);
 190         dev_dbg(dev, "rstatus=%d\n", usblp->rstatus);
 191         dev_dbg(dev, "quirks=%d\n", usblp->quirks);
 192         dev_dbg(dev, "used=%d\n", usblp->used);
 193         dev_dbg(dev, "bidir=%d\n", usblp->bidir);
 194         dev_dbg(dev, "device_id_string=\"%s\"\n",
 195                 usblp->device_id_string ?
 196                         usblp->device_id_string + 2 :
 197                         (unsigned char *)"(null)");
 198 }
 199 #endif
 200
 201 /* Quirks: various printer quirks are handled by this table & its flags. */
 202
 203 struct quirk_printer_struct {
 204         __u16 vendorId;
 205         __u16 productId;
 206         unsigned int quirks;
 207 };
 208
 209 #define USBLP_QUIRK_BIDIR       0x1     /* reports bidir but requires unidirectional mode (no INs/reads) */
 210 #define USBLP_QUIRK_USB_INIT    0x2     /* needs vendor USB init string */
 211 #define USBLP_QUIRK_BAD_CLASS   0x4     /* descriptor uses vendor-specific Class or SubClass */
 212
 213 static const struct quirk_printer_struct quirk_printers[] = {
 214         { 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
 215         { 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
 216         { 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
 217         { 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
 218         { 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
 219         { 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
 220         { 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */
 221         { 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */
 222         { 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
 223         { 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
 224         { 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
 225         { 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
 226         { 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
 227         { 0x0482, 0x0010, USBLP_QUIRK_BIDIR }, /* Kyocera Mita FS 820, by zut <kernel@zut.de> */
 228         { 0x04f9, 0x000d, USBLP_QUIRK_BIDIR }, /* Brother Industries, Ltd HL-1440 Laser Printer */
 229         { 0x04b8, 0x0202, USBLP_QUIRK_BAD_CLASS }, /* Seiko Epson Receipt Printer M129C */
 230         { 0, 0 }
 231 };
 232
 233 static int usblp_wwait(struct usblp *usblp, int nonblock);
 234 static int usblp_wtest(struct usblp *usblp, int nonblock);
 235 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock);
 236 static int usblp_rtest(struct usblp *usblp, int nonblock);
 237 static int usblp_submit_read(struct usblp *usblp);
 238 static int usblp_select_alts(struct usblp *usblp);
 239 static int usblp_set_protocol(struct usblp *usblp, int protocol);
 240 static int usblp_cache_device_id_string(struct usblp *usblp);
 241
 242 /* forward reference to make our lives easier */
 243 static struct usb_driver usblp_driver;
 244 static DEFINE_MUTEX(usblp_mutex);       /* locks the existence of usblp's */
 245
 246 /*
 247  * Functions for usblp control messages.
 248  */
 249
 250 static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
 251 {
 252         int retval;
 253         int index = usblp->ifnum;
 254
 255         /* High byte has the interface index.
 256            Low byte has the alternate setting.
 257          */
 258         if ((request == USBLP_REQ_GET_ID) && (type == USB_TYPE_CLASS))
 259                 index = (usblp->ifnum<<8)|usblp->protocol[usblp->current_protocol].alt_setting;
 260
 261         retval = usb_control_msg(usblp->dev,
 262                 dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
 263                 request, type | dir | recip, value, index, buf, len, USBLP_CTL_TIMEOUT);
 264         dev_dbg(&usblp->intf->dev,
 265                 "usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d idx: %d len: %#x result: %d\n",
 266                 request, !!dir, recip, value, index, len, retval);
 267         return retval < 0 ? retval : 0;
 268 }
 269
 270 #define usblp_read_status(usblp, status)\
 271         usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
 272 #define usblp_get_id(usblp, config, id, maxlen)\
 273         usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
 274 #define usblp_reset(usblp)\
 275         usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)
 276
 277 #define usblp_hp_channel_change_request(usblp, channel, buffer) \
 278         usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)
 279
 280 /*
 281  * See the description for usblp_select_alts() below for the usage
 282  * explanation.  Look into your /sys/kernel/debug/usb/devices and dmesg in
 283  * case of any trouble.
 284  */
 285 static int proto_bias = -1;
 286
 287 /*
 288  * URB callback.
 289  */
 290
 291 static void usblp_bulk_read(struct urb *urb)
 292 {
 293         struct usblp *usblp = urb->context;
 294         int status = urb->status;
 295         unsigned long flags;
 296
 297         if (usblp->present && usblp->used) {
 298                 if (status)
 299                         printk(KERN_WARNING "usblp%d: "
 300                             "nonzero read bulk status received: %d\n",
 301                             usblp->minor, status);
 302         }
 303         spin_lock_irqsave(&usblp->lock, flags);
 304         if (status < 0)
 305                 usblp->rstatus = status;
 306         else
 307                 usblp->rstatus = urb->actual_length;
 308         usblp->rcomplete = 1;
 309         wake_up(&usblp->rwait);
 310         spin_unlock_irqrestore(&usblp->lock, flags);
 311
 312         usb_free_urb(urb);
 313 }
 314
 315 static void usblp_bulk_write(struct urb *urb)
 316 {
 317         struct usblp *usblp = urb->context;
 318         int status = urb->status;
 319         unsigned long flags;
 320
 321         if (usblp->present && usblp->used) {
 322                 if (status)
 323                         printk(KERN_WARNING "usblp%d: "
 324                             "nonzero write bulk status received: %d\n",
 325                             usblp->minor, status);
 326         }
 327         spin_lock_irqsave(&usblp->lock, flags);
 328         if (status < 0)
 329                 usblp->wstatus = status;
 330         else
 331                 usblp->wstatus = urb->actual_length;
 332         usblp->no_paper = 0;
 333         usblp->wcomplete = 1;
 334         wake_up(&usblp->wwait);
 335         spin_unlock_irqrestore(&usblp->lock, flags);
 336
 337         usb_free_urb(urb);
 338 }
 339
 340 /*
 341  * Get and print printer errors.
 342  */
 343
 344 static const char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };
 345
 346 static int usblp_check_status(struct usblp *usblp, int err)
 347 {
 348         unsigned char status, newerr = 0;
 349         int error;
 350
 351         mutex_lock(&usblp->mut);
 352         if ((error = usblp_read_status(usblp, usblp->statusbuf)) < 0) {
 353                 mutex_unlock(&usblp->mut);
 354                 printk_ratelimited(KERN_ERR
 355                                 "usblp%d: error %d reading printer status\n",
 356                                 usblp->minor, error);
 357                 return 0;
 358         }
 359         status = *usblp->statusbuf;
 360         mutex_unlock(&usblp->mut);
 361
 362         if (~status & LP_PERRORP)
 363                 newerr = 3;
 364         if (status & LP_POUTPA)
 365                 newerr = 1;
 366         if (~status & LP_PSELECD)
 367                 newerr = 2;
 368
 369         if (newerr != err) {
 370                 printk(KERN_INFO "usblp%d: %s\n",
 371                    usblp->minor, usblp_messages[newerr]);
 372         }
 373
 374         return newerr;
 375 }
 376
 377 static int handle_bidir(struct usblp *usblp)
 378 {
 379         if (usblp->bidir && usblp->used) {
 380                 if (usblp_submit_read(usblp) < 0)
 381                         return -EIO;
 382         }
 383         return 0;
 384 }
 385
 386 /*
 387  * File op functions.
 388  */
 389
 390 static int usblp_open(struct inode *inode, struct file *file)
 391 {
 392         int minor = iminor(inode);
 393         struct usblp *usblp;
 394         struct usb_interface *intf;
 395         int retval;
 396
 397         if (minor < 0)
 398                 return -ENODEV;
 399
 400         mutex_lock(&usblp_mutex);
 401
 402         retval = -ENODEV;
 403         intf = usb_find_interface(&usblp_driver, minor);
 404         if (!intf)
 405                 goto out;
 406         usblp = usb_get_intfdata(intf);
 407         if (!usblp || !usblp->dev || !usblp->present)
 408                 goto out;
 409
 410         retval = -EBUSY;
 411         if (usblp->used)
 412                 goto out;
 413
 414         /*
 415          * We do not implement LP_ABORTOPEN/LPABORTOPEN for two reasons:
 416          *  - We do not want persistent state which close(2) does not clear
 417          *  - It is not used anyway, according to CUPS people
 418          */
 419
 420         retval = usb_autopm_get_interface(intf);
 421         if (retval < 0)
 422                 goto out;
 423         usblp->used = 1;
 424         file->private_data = usblp;
 425
 426         usblp->wcomplete = 1; /* we begin writeable */
 427         usblp->wstatus = 0;
 428         usblp->rcomplete = 0;
 429
 430         if (handle_bidir(usblp) < 0) {
 431                 usb_autopm_put_interface(intf);
 432                 usblp->used = 0;
 433                 file->private_data = NULL;
 434                 retval = -EIO;
 435         }
 436 out:
 437         mutex_unlock(&usblp_mutex);
 438         return retval;
 439 }
 440
 441 static void usblp_cleanup(struct usblp *usblp)
 442 {
 443         printk(KERN_INFO "usblp%d: removed\n", usblp->minor);
 444
 445         kfree(usblp->readbuf);
 446         kfree(usblp->device_id_string);
 447         kfree(usblp->statusbuf);
 448         usb_put_intf(usblp->intf);
 449         kfree(usblp);
 450 }
 451
 452 static void usblp_unlink_urbs(struct usblp *usblp)
 453 {
 454         usb_kill_anchored_urbs(&usblp->urbs);
 455 }
 456
 457 static int usblp_release(struct inode *inode, struct file *file)
 458 {
 459         struct usblp *usblp = file->private_data;
 460
 461         usblp->flags &= ~LP_ABORT;
 462
 463         mutex_lock(&usblp_mutex);
 464         usblp->used = 0;
 465         if (usblp->present)
 466                 usblp_unlink_urbs(usblp);
 467
 468         usb_autopm_put_interface(usblp->intf);
 469
 470         if (!usblp->present)            /* finish cleanup from disconnect */
 471                 usblp_cleanup(usblp);
 472         mutex_unlock(&usblp_mutex);
 473         return 0;
 474 }
 475
 476 /* No kernel lock - fine */
 477 static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
 478 {
 479         __poll_t ret;
 480         unsigned long flags;
 481
 482         struct usblp *usblp = file->private_data;
 483         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 484         poll_wait(file, &usblp->rwait, wait);
 485         poll_wait(file, &usblp->wwait, wait);
 486         spin_lock_irqsave(&usblp->lock, flags);
 487         ret = ((usblp->bidir && usblp->rcomplete) ? EPOLLIN  | EPOLLRDNORM : 0) |
 488            ((usblp->no_paper || usblp->wcomplete) ? EPOLLOUT | EPOLLWRNORM : 0);
 489         spin_unlock_irqrestore(&usblp->lock, flags);
 490         return ret;
 491 }
 492
 493 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 494 {
 495         struct usblp *usblp = file->private_data;
 496         int length, err, i;
 497         unsigned char newChannel;
 498         int status;
 499         int twoints[2];
 500         int retval = 0;
 501
 502         mutex_lock(&usblp->mut);
 503         if (!usblp->present) {
 504                 retval = -ENODEV;
 505                 goto done;
 506         }
 507
 508         dev_dbg(&usblp->intf->dev,
 509                 "usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
 510                 _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 511
 512         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 513
 514                 switch (_IOC_NR(cmd)) {
 515
 516                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 517                         if (_IOC_DIR(cmd) != _IOC_READ) {
 518                                 retval = -EINVAL;
 519                                 goto done;
 520                         }
 521
 522                         length = usblp_cache_device_id_string(usblp);
 523                         if (length < 0) {
 524                                 retval = length;
 525                                 goto done;
 526                         }
 527                         if (length > _IOC_SIZE(cmd))
 528                                 length = _IOC_SIZE(cmd); /* truncate */
 529
 530                         if (copy_to_user((void __user *) arg,
 531                                         usblp->device_id_string,
 532                                         (unsigned long) length)) {
 533                                 retval = -EFAULT;
 534                                 goto done;
 535                         }
 536
 537                         break;
 538
 539                 case IOCNR_GET_PROTOCOLS:
 540                         if (_IOC_DIR(cmd) != _IOC_READ ||
 541                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 542                                 retval = -EINVAL;
 543                                 goto done;
 544                         }
 545
 546                         twoints[0] = usblp->current_protocol;
 547                         twoints[1] = 0;
 548                         for (i = USBLP_FIRST_PROTOCOL;
 549                              i <= USBLP_LAST_PROTOCOL; i++) {
 550                                 if (usblp->protocol[i].alt_setting >= 0)
 551                                         twoints[1] |= (1<<i);
 552                         }
 553
 554                         if (copy_to_user((void __user *)arg,
 555                                         (unsigned char *)twoints,
 556                                         sizeof(twoints))) {
 557                                 retval = -EFAULT;
 558                                 goto done;
 559                         }
 560
 561                         break;
 562
 563                 case IOCNR_SET_PROTOCOL:
 564                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
 565                                 retval = -EINVAL;
 566                                 goto done;
 567                         }
 568
 569 #ifdef DEBUG
 570                         if (arg == -10) {
 571                                 usblp_dump(usblp);
 572                                 break;
 573                         }
 574 #endif
 575
 576                         usblp_unlink_urbs(usblp);
 577                         retval = usblp_set_protocol(usblp, arg);
 578                         if (retval < 0) {
 579                                 usblp_set_protocol(usblp,
 580                                         usblp->current_protocol);
 581                         }
 582                         break;
 583
 584                 case IOCNR_HP_SET_CHANNEL:
 585                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
 586                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 587                             usblp->quirks & USBLP_QUIRK_BIDIR) {
 588                                 retval = -EINVAL;
 589                                 goto done;
 590                         }
 591
 592                         err = usblp_hp_channel_change_request(usblp,
 593                                 arg, &newChannel);
 594                         if (err < 0) {
 595                                 dev_err(&usblp->dev->dev,
 596                                         "usblp%d: error = %d setting "
 597                                         "HP channel\n",
 598                                         usblp->minor, err);
 599                                 retval = -EIO;
 600                                 goto done;
 601                         }
 602
 603                         dev_dbg(&usblp->intf->dev,
 604                                 "usblp%d requested/got HP channel %ld/%d\n",
 605                                 usblp->minor, arg, newChannel);
 606                         break;
 607
 608                 case IOCNR_GET_BUS_ADDRESS:
 609                         if (_IOC_DIR(cmd) != _IOC_READ ||
 610                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 611                                 retval = -EINVAL;
 612                                 goto done;
 613                         }
 614
 615                         twoints[0] = usblp->dev->bus->busnum;
 616                         twoints[1] = usblp->dev->devnum;
 617                         if (copy_to_user((void __user *)arg,
 618                                         (unsigned char *)twoints,
 619                                         sizeof(twoints))) {
 620                                 retval = -EFAULT;
 621                                 goto done;
 622                         }
 623
 624                         dev_dbg(&usblp->intf->dev,
 625                                 "usblp%d is bus=%d, device=%d\n",
 626                                 usblp->minor, twoints[0], twoints[1]);
 627                         break;
 628
 629                 case IOCNR_GET_VID_PID:
 630                         if (_IOC_DIR(cmd) != _IOC_READ ||
 631                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 632                                 retval = -EINVAL;
 633                                 goto done;
 634                         }
 635
 636                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 637                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 638                         if (copy_to_user((void __user *)arg,
 639                                         (unsigned char *)twoints,
 640                                         sizeof(twoints))) {
 641                                 retval = -EFAULT;
 642                                 goto done;
 643                         }
 644
 645                         dev_dbg(&usblp->intf->dev,
 646                                 "usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
 647                                 usblp->minor, twoints[0], twoints[1]);
 648                         break;
 649
 650                 case IOCNR_SOFT_RESET:
 651                         if (_IOC_DIR(cmd) != _IOC_NONE) {
 652                                 retval = -EINVAL;
 653                                 goto done;
 654                         }
 655                         retval = usblp_reset(usblp);
 656                         break;
 657                 default:
 658                         retval = -ENOTTY;
 659                 }
 660         else    /* old-style ioctl value */
 661                 switch (cmd) {
 662
 663                 case LPGETSTATUS:
 664                         retval = usblp_read_status(usblp, usblp->statusbuf);
 665                         if (retval) {
 666                                 printk_ratelimited(KERN_ERR "usblp%d:"
 667                                             "failed reading printer status (%d)\n",
 668                                             usblp->minor, retval);
 669                                 retval = -EIO;
 670                                 goto done;
 671                         }
 672                         status = *usblp->statusbuf;
 673                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 674                                 retval = -EFAULT;
 675                         break;
 676
 677                 case LPABORT:
 678                         if (arg)
 679                                 usblp->flags |= LP_ABORT;
 680                         else
 681                                 usblp->flags &= ~LP_ABORT;
 682                         break;
 683
 684                 default:
 685                         retval = -ENOTTY;
 686                 }
 687
 688 done:
 689         mutex_unlock(&usblp->mut);
 690         return retval;
 691 }
 692
 693 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 694 {
 695         struct urb *urb;
 696         char *writebuf;
 697
 698         writebuf = kmalloc(transfer_length, GFP_KERNEL);
 699         if (writebuf == NULL)
 700                 return NULL;
 701         urb = usb_alloc_urb(0, GFP_KERNEL);
 702         if (urb == NULL) {
 703                 kfree(writebuf);
 704                 return NULL;
 705         }
 706
 707         usb_fill_bulk_urb(urb, usblp->dev,
 708                 usb_sndbulkpipe(usblp->dev,
 709                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 710                 writebuf, transfer_length, usblp_bulk_write, usblp);
 711         urb->transfer_flags |= URB_FREE_BUFFER;
 712
 713         return urb;
 714 }
 715
 716 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 717 {
 718         struct usblp *usblp = file->private_data;
 719         struct urb *writeurb;
 720         int rv;
 721         int transfer_length;
 722         ssize_t writecount = 0;
 723
 724         if (mutex_lock_interruptible(&usblp->wmut)) {
 725                 rv = -EINTR;
 726                 goto raise_biglock;
 727         }
 728         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 729                 goto raise_wait;
 730
 731         while (writecount < count) {
 732                 /*
 733                  * Step 1: Submit next block.
 734                  */
 735                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 736                         transfer_length = USBLP_BUF_SIZE;
 737
 738                 rv = -ENOMEM;
 739                 writeurb = usblp_new_writeurb(usblp, transfer_length);
 740                 if (writeurb == NULL)
 741                         goto raise_urb;
 742                 usb_anchor_urb(writeurb, &usblp->urbs);
 743
 744                 if (copy_from_user(writeurb->transfer_buffer,
 745                                    buffer + writecount, transfer_length)) {
 746                         rv = -EFAULT;
 747                         goto raise_badaddr;
 748                 }
 749
 750                 spin_lock_irq(&usblp->lock);
 751                 usblp->wcomplete = 0;
 752                 spin_unlock_irq(&usblp->lock);
 753                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 754                         usblp->wstatus = 0;
 755                         spin_lock_irq(&usblp->lock);
 756                         usblp->no_paper = 0;
 757                         usblp->wcomplete = 1;
 758                         wake_up(&usblp->wwait);
 759                         spin_unlock_irq(&usblp->lock);
 760                         if (rv != -ENOMEM)
 761                                 rv = -EIO;
 762                         goto raise_submit;
 763                 }
 764
 765                 /*
 766                  * Step 2: Wait for transfer to end, collect results.
 767                  */
 768                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 769                 if (rv < 0) {
 770                         if (rv == -EAGAIN) {
 771                                 /* Presume that it's going to complete well. */
 772                                 writecount += transfer_length;
 773                         }
 774                         if (rv == -ENOSPC) {
 775                                 spin_lock_irq(&usblp->lock);
 776                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 777                                 spin_unlock_irq(&usblp->lock);
 778                                 writecount += transfer_length;
 779                         }
 780                         /* Leave URB dangling, to be cleaned on close. */
 781                         goto collect_error;
 782                 }
 783
 784                 if (usblp->wstatus < 0) {
 785                         rv = -EIO;
 786                         goto collect_error;
 787                 }
 788                 /*
 789                  * This is critical: it must be our URB, not other writer's.
 790                  * The wmut exists mainly to cover us here.
 791                  */
 792                 writecount += usblp->wstatus;
 793         }
 794
 795         mutex_unlock(&usblp->wmut);
 796         return writecount;
 797
 798 raise_submit:
 799 raise_badaddr:
 800         usb_unanchor_urb(writeurb);
 801         usb_free_urb(writeurb);
 802 raise_urb:
 803 raise_wait:
 804 collect_error:          /* Out of raise sequence */
 805         mutex_unlock(&usblp->wmut);
 806 raise_biglock:
 807         return writecount ? writecount : rv;
 808 }
 809
 810 /*
 811  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 812  * error, etc. This is the historical behaviour. In all such cases we return
 813  * EIO, and applications loop in order to get the new read going.
 814  */
 815 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 816 {
 817         struct usblp *usblp = file->private_data;
 818         ssize_t count;
 819         ssize_t avail;
 820         int rv;
 821
 822         if (!usblp->bidir)
 823                 return -EINVAL;
 824
 825         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 826         if (rv < 0)
 827                 return rv;
 828
 829         if ((avail = usblp->rstatus) < 0) {
 830                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 831                     usblp->minor, (int)avail);
 832                 usblp_submit_read(usblp);
 833                 count = -EIO;
 834                 goto done;
 835         }
 836
 837         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 838         if (count != 0 &&
 839             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 840                 count = -EFAULT;
 841                 goto done;
 842         }
 843
 844         if ((usblp->readcount += count) == avail) {
 845                 if (usblp_submit_read(usblp) < 0) {
 846                         /* We don't want to leak USB return codes into errno. */
 847                         if (count == 0)
 848                                 count = -EIO;
 849                         goto done;
 850                 }
 851         }
 852
 853 done:
 854         mutex_unlock(&usblp->mut);
 855         return count;
 856 }
 857
 858 /*
 859  * Wait for the write path to come idle.
 860  * This is called under the ->wmut, so the idle path stays idle.
 861  *
 862  * Our write path has a peculiar property: it does not buffer like a tty,
 863  * but waits for the write to succeed. This allows our ->release to bug out
 864  * without waiting for writes to drain. But it obviously does not work
 865  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 866  * select(2) or poll(2) to wait for the buffer to drain before closing.
 867  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 868  */
 869 static int usblp_wwait(struct usblp *usblp, int nonblock)
 870 {
 871         DECLARE_WAITQUEUE(waita, current);
 872         int rc;
 873         int err = 0;
 874
 875         add_wait_queue(&usblp->wwait, &waita);
 876         for (;;) {
 877                 if (mutex_lock_interruptible(&usblp->mut)) {
 878                         rc = -EINTR;
 879                         break;
 880                 }
 881                 set_current_state(TASK_INTERRUPTIBLE);
 882                 rc = usblp_wtest(usblp, nonblock);
 883                 mutex_unlock(&usblp->mut);
 884                 if (rc <= 0)
 885                         break;
 886
 887                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 888                         if (usblp->flags & LP_ABORT) {
 889                                 err = usblp_check_status(usblp, err);
 890                                 if (err == 1) { /* Paper out */
 891                                         rc = -ENOSPC;
 892                                         break;
 893                                 }
 894                         } else {
 895                                 /* Prod the printer, Gentoo#251237. */
 896                                 mutex_lock(&usblp->mut);
 897                                 usblp_read_status(usblp, usblp->statusbuf);
 898                                 mutex_unlock(&usblp->mut);
 899                         }
 900                 }
 901         }
 902         set_current_state(TASK_RUNNING);
 903         remove_wait_queue(&usblp->wwait, &waita);
 904         return rc;
 905 }
 906
 907 static int usblp_wtest(struct usblp *usblp, int nonblock)
 908 {
 909         unsigned long flags;
 910
 911         if (!usblp->present)
 912                 return -ENODEV;
 913         if (signal_pending(current))
 914                 return -EINTR;
 915         spin_lock_irqsave(&usblp->lock, flags);
 916         if (usblp->wcomplete) {
 917                 spin_unlock_irqrestore(&usblp->lock, flags);
 918                 return 0;
 919         }
 920         spin_unlock_irqrestore(&usblp->lock, flags);
 921         if (nonblock)
 922                 return -EAGAIN;
 923         return 1;
 924 }
 925
 926 /*
 927  * Wait for read bytes to become available. This probably should have been
 928  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 929  * name for functions which lock and return.
 930  *
 931  * We do not use wait_event_interruptible because it makes locking iffy.
 932  */
 933 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 934 {
 935         DECLARE_WAITQUEUE(waita, current);
 936         int rc;
 937
 938         add_wait_queue(&usblp->rwait, &waita);
 939         for (;;) {
 940                 if (mutex_lock_interruptible(&usblp->mut)) {
 941                         rc = -EINTR;
 942                         break;
 943                 }
 944                 set_current_state(TASK_INTERRUPTIBLE);
 945                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 946                         mutex_unlock(&usblp->mut);
 947                         break;
 948                 }
 949                 if (rc == 0)    /* Keep it locked */
 950                         break;
 951                 mutex_unlock(&usblp->mut);
 952                 schedule();
 953         }
 954         set_current_state(TASK_RUNNING);
 955         remove_wait_queue(&usblp->rwait, &waita);
 956         return rc;
 957 }
 958
 959 static int usblp_rtest(struct usblp *usblp, int nonblock)
 960 {
 961         unsigned long flags;
 962
 963         if (!usblp->present)
 964                 return -ENODEV;
 965         if (signal_pending(current))
 966                 return -EINTR;
 967         spin_lock_irqsave(&usblp->lock, flags);
 968         if (usblp->rcomplete) {
 969                 spin_unlock_irqrestore(&usblp->lock, flags);
 970                 return 0;
 971         }
 972         spin_unlock_irqrestore(&usblp->lock, flags);
 973         if (nonblock)
 974                 return -EAGAIN;
 975         return 1;
 976 }
 977
 978 /*
 979  * Please check ->bidir and other such things outside for now.
 980  */
 981 static int usblp_submit_read(struct usblp *usblp)
 982 {
 983         struct urb *urb;
 984         unsigned long flags;
 985         int rc;
 986
 987         rc = -ENOMEM;
 988         urb = usb_alloc_urb(0, GFP_KERNEL);
 989         if (urb == NULL)
 990                 goto raise_urb;
 991
 992         usb_fill_bulk_urb(urb, usblp->dev,
 993                 usb_rcvbulkpipe(usblp->dev,
 994                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
 995                 usblp->readbuf, USBLP_BUF_SIZE_IN,
 996                 usblp_bulk_read, usblp);
 997         usb_anchor_urb(urb, &usblp->urbs);
 998
 999         spin_lock_irqsave(&usblp->lock, flags);
1000         usblp->readcount = 0; /* XXX Why here? */
1001         usblp->rcomplete = 0;
1002         spin_unlock_irqrestore(&usblp->lock, flags);
1003         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1004                 dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1005                 spin_lock_irqsave(&usblp->lock, flags);
1006                 usblp->rstatus = rc;
1007                 usblp->rcomplete = 1;
1008                 spin_unlock_irqrestore(&usblp->lock, flags);
1009                 goto raise_submit;
1010         }
1011
1012         return 0;
1013
1014 raise_submit:
1015         usb_unanchor_urb(urb);
1016         usb_free_urb(urb);
1017 raise_urb:
1018         return rc;
1019 }
1020
1021 /*
1022  * Checks for printers that have quirks, such as requiring unidirectional
1023  * communication but reporting bidirectional; currently some HP printers
1024  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1025  * sent at each open (like some Epsons).
1026  * Returns 1 if found, 0 if not found.
1027  *
1028  * HP recommended that we use the bidirectional interface but
1029  * don't attempt any bulk IN transfers from the IN endpoint.
1030  * Here's some more detail on the problem:
1031  * The problem is not that it isn't bidirectional though. The problem
1032  * is that if you request a device ID, or status information, while
1033  * the buffers are full, the return data will end up in the print data
1034  * buffer. For example if you make sure you never request the device ID
1035  * while you are sending print data, and you don't try to query the
1036  * printer status every couple of milliseconds, you will probably be OK.
1037  */
1038 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1039 {
1040         int i;
1041
1042         for (i = 0; quirk_printers[i].vendorId; i++) {
1043                 if (vendor == quirk_printers[i].vendorId &&
1044                     product == quirk_printers[i].productId)
1045                         return quirk_printers[i].quirks;
1046         }
1047         return 0;
1048 }
1049
1050 static const struct file_operations usblp_fops = {
1051         .owner =        THIS_MODULE,
1052         .read =         usblp_read,
1053         .write =        usblp_write,
1054         .poll =         usblp_poll,
1055         .unlocked_ioctl =       usblp_ioctl,
1056         .compat_ioctl =         usblp_ioctl,
1057         .open =         usblp_open,
1058         .release =      usblp_release,
1059         .llseek =       noop_llseek,
1060 };
1061
1062 static char *usblp_devnode(struct device *dev, umode_t *mode)
1063 {
1064         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1065 }
1066
1067 static struct usb_class_driver usblp_class = {
1068         .name =         "lp%d",
1069         .devnode =      usblp_devnode,
1070         .fops =         &usblp_fops,
1071         .minor_base =   USBLP_MINOR_BASE,
1072 };
1073
1074 static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1075 {
1076         struct usb_interface *intf = to_usb_interface(dev);
1077         struct usblp *usblp = usb_get_intfdata(intf);
1078
1079         if (usblp->device_id_string[0] == 0 &&
1080             usblp->device_id_string[1] == 0)
1081                 return 0;
1082
1083         return sprintf(buf, "%s", usblp->device_id_string+2);
1084 }
1085
1086 static DEVICE_ATTR_RO(ieee1284_id);
1087
1088 static int usblp_probe(struct usb_interface *intf,
1089                        const struct usb_device_id *id)
1090 {
1091         struct usb_device *dev = interface_to_usbdev(intf);
1092         struct usblp *usblp;
1093         int protocol;
1094         int retval;
1095
1096         /* Malloc and start initializing usblp structure so we can use it
1097          * directly. */
1098         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1099         if (!usblp) {
1100                 retval = -ENOMEM;
1101                 goto abort_ret;
1102         }
1103         usblp->dev = dev;
1104         mutex_init(&usblp->wmut);
1105         mutex_init(&usblp->mut);
1106         spin_lock_init(&usblp->lock);
1107         init_waitqueue_head(&usblp->rwait);
1108         init_waitqueue_head(&usblp->wwait);
1109         init_usb_anchor(&usblp->urbs);
1110         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1111         usblp->intf = usb_get_intf(intf);
1112
1113         /* Malloc device ID string buffer to the largest expected length,
1114          * since we can re-query it on an ioctl and a dynamic string
1115          * could change in length. */
1116         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1117                 retval = -ENOMEM;
1118                 goto abort;
1119         }
1120
1121         /*
1122          * Allocate read buffer. We somewhat wastefully
1123          * malloc both regardless of bidirectionality, because the
1124          * alternate setting can be changed later via an ioctl.
1125          */
1126         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1127                 retval = -ENOMEM;
1128                 goto abort;
1129         }
1130
1131         /* Allocate buffer for printer status */
1132         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1133         if (!usblp->statusbuf) {
1134                 retval = -ENOMEM;
1135                 goto abort;
1136         }
1137
1138         /* Lookup quirks for this printer. */
1139         usblp->quirks = usblp_quirks(
1140                 le16_to_cpu(dev->descriptor.idVendor),
1141                 le16_to_cpu(dev->descriptor.idProduct));
1142
1143         /* Analyze and pick initial alternate settings and endpoints. */
1144         protocol = usblp_select_alts(usblp);
1145         if (protocol < 0) {
1146                 dev_dbg(&intf->dev,
1147                         "incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1148                         le16_to_cpu(dev->descriptor.idVendor),
1149                         le16_to_cpu(dev->descriptor.idProduct));
1150                 retval = -ENODEV;
1151                 goto abort;
1152         }
1153
1154         /* Setup the selected alternate setting and endpoints. */
1155         if (usblp_set_protocol(usblp, protocol) < 0) {
1156                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1157                 goto abort;
1158         }
1159
1160         /* Retrieve and store the device ID string. */
1161         usblp_cache_device_id_string(usblp);
1162         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1163         if (retval)
1164                 goto abort_intfdata;
1165
1166 #ifdef DEBUG
1167         usblp_check_status(usblp, 0);
1168 #endif
1169
1170         usb_set_intfdata(intf, usblp);
1171
1172         usblp->present = 1;
1173
1174         retval = usb_register_dev(intf, &usblp_class);
1175         if (retval) {
1176                 dev_err(&intf->dev,
1177                         "usblp: Not able to get a minor (base %u, slice default): %d\n",
1178                         USBLP_MINOR_BASE, retval);
1179                 goto abort_intfdata;
1180         }
1181         usblp->minor = intf->minor;
1182         dev_info(&intf->dev,
1183                 "usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1184                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1185                 usblp->ifnum,
1186                 usblp->protocol[usblp->current_protocol].alt_setting,
1187                 usblp->current_protocol,
1188                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1189                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1190
1191         return 0;
1192
1193 abort_intfdata:
1194         usb_set_intfdata(intf, NULL);
1195         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1196 abort:
1197         kfree(usblp->readbuf);
1198         kfree(usblp->statusbuf);
1199         kfree(usblp->device_id_string);
1200         usb_put_intf(usblp->intf);
1201         kfree(usblp);
1202 abort_ret:
1203         return retval;
1204 }
1205
1206 /*
1207  * We are a "new" style driver with usb_device_id table,
1208  * but our requirements are too intricate for simple match to handle.
1209  *
1210  * The "proto_bias" option may be used to specify the preferred protocol
1211  * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1212  * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1213  * then we bind to it.
1214  *
1215  * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1216  * is compatible with a stream of characters. If we find it, we bind to it.
1217  *
1218  * Note that the people from hpoj.sourceforge.net need to be able to
1219  * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1220  * for this purpose.
1221  *
1222  * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1223  * even though it's probably not stream-compatible, because this matches
1224  * the behaviour of the old code.
1225  *
1226  * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1227  * - the unidirectional interface.
1228  */
1229 static int usblp_select_alts(struct usblp *usblp)
1230 {
1231         struct usb_interface *if_alt;
1232         struct usb_host_interface *ifd;
1233         struct usb_endpoint_descriptor *epwrite, *epread;
1234         int p, i;
1235         int res;
1236
1237         if_alt = usblp->intf;
1238
1239         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1240                 usblp->protocol[p].alt_setting = -1;
1241
1242         /* Find out what we have. */
1243         for (i = 0; i < if_alt->num_altsetting; i++) {
1244                 ifd = &if_alt->altsetting[i];
1245
1246                 if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1247                     ifd->desc.bInterfaceSubClass != 1)
1248                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1249                                 continue;
1250
1251                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1252                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1253                         continue;
1254
1255                 /* Look for the expected bulk endpoints. */
1256                 if (ifd->desc.bInterfaceProtocol > 1) {
1257                         res = usb_find_common_endpoints(ifd,
1258                                         &epread, &epwrite, NULL, NULL);
1259                 } else {
1260                         epread = NULL;
1261                         res = usb_find_bulk_out_endpoint(ifd, &epwrite);
1262                 }
1263
1264                 /* Ignore buggy hardware without the right endpoints. */
1265                 if (res)
1266                         continue;
1267
1268                 /* Turn off reads for buggy bidirectional printers. */
1269                 if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1270                         printk(KERN_INFO "usblp%d: Disabling reads from "
1271                             "problematic bidirectional printer\n",
1272                             usblp->minor);
1273                         epread = NULL;
1274                 }
1275
1276                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1277                                 ifd->desc.bAlternateSetting;
1278                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1279                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1280         }
1281
1282         /* If our requested protocol is supported, then use it. */
1283         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1284             proto_bias <= USBLP_LAST_PROTOCOL &&
1285             usblp->protocol[proto_bias].alt_setting != -1)
1286                 return proto_bias;
1287
1288         /* Ordering is important here. */
1289         if (usblp->protocol[2].alt_setting != -1)
1290                 return 2;
1291         if (usblp->protocol[1].alt_setting != -1)
1292                 return 1;
1293         if (usblp->protocol[3].alt_setting != -1)
1294                 return 3;
1295
1296         /* If nothing is available, then don't bind to this device. */
1297         return -1;
1298 }
1299
1300 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1301 {
1302         int r, alts;
1303
1304         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1305                 return -EINVAL;
1306
1307         alts = usblp->protocol[protocol].alt_setting;
1308         if (alts < 0)
1309                 return -EINVAL;
1310         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1311         if (r < 0) {
1312                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1313                         alts, usblp->ifnum);
1314                 return r;
1315         }
1316
1317         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1318         usblp->current_protocol = protocol;
1319         dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1320                 usblp->minor, protocol);
1321         return 0;
1322 }
1323
1324 /* Retrieves and caches device ID string.
1325  * Returns length, including length bytes but not null terminator.
1326  * On error, returns a negative errno value. */
1327 static int usblp_cache_device_id_string(struct usblp *usblp)
1328 {
1329         int err, length;
1330
1331         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1332         if (err < 0) {
1333                 dev_dbg(&usblp->intf->dev,
1334                         "usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1335                         usblp->minor, err);
1336                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1337                 return -EIO;
1338         }
1339
1340         /* First two bytes are length in big-endian.
1341          * They count themselves, and we copy them into
1342          * the user's buffer. */
1343         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1344         if (length < 2)
1345                 length = 2;
1346         else if (length >= USBLP_DEVICE_ID_SIZE)
1347                 length = USBLP_DEVICE_ID_SIZE - 1;
1348         usblp->device_id_string[length] = '\0';
1349
1350         dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1351                 usblp->minor, length, &usblp->device_id_string[2]);
1352
1353         return length;
1354 }
1355
1356 static void usblp_disconnect(struct usb_interface *intf)
1357 {
1358         struct usblp *usblp = usb_get_intfdata(intf);
1359
1360         usb_deregister_dev(intf, &usblp_class);
1361
1362         if (!usblp || !usblp->dev) {
1363                 dev_err(&intf->dev, "bogus disconnect\n");
1364                 BUG();
1365         }
1366
1367         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1368
1369         mutex_lock(&usblp_mutex);
1370         mutex_lock(&usblp->mut);
1371         usblp->present = 0;
1372         wake_up(&usblp->wwait);
1373         wake_up(&usblp->rwait);
1374         usb_set_intfdata(intf, NULL);
1375
1376         usblp_unlink_urbs(usblp);
1377         mutex_unlock(&usblp->mut);
1378
1379         if (!usblp->used)
1380                 usblp_cleanup(usblp);
1381         mutex_unlock(&usblp_mutex);
1382 }
1383
1384 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1385 {
1386         struct usblp *usblp = usb_get_intfdata(intf);
1387
1388         usblp_unlink_urbs(usblp);
1389 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1390         /* not strictly necessary, but just in case */
1391         wake_up(&usblp->wwait);
1392         wake_up(&usblp->rwait);
1393 #endif
1394
1395         return 0;
1396 }
1397
1398 static int usblp_resume(struct usb_interface *intf)
1399 {
1400         struct usblp *usblp = usb_get_intfdata(intf);
1401         int r;
1402
1403         r = handle_bidir(usblp);
1404
1405         return r;
1406 }
1407
1408 static const struct usb_device_id usblp_ids[] = {
1409         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1410         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1411         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1412         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1413         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1414         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1415         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1416         { }                                             /* Terminating entry */
1417 };
1418
1419 MODULE_DEVICE_TABLE(usb, usblp_ids);
1420
1421 static struct usb_driver usblp_driver = {
1422         .name =         "usblp",
1423         .probe =        usblp_probe,
1424         .disconnect =   usblp_disconnect,
1425         .suspend =      usblp_suspend,
1426         .resume =       usblp_resume,
1427         .id_table =     usblp_ids,
1428         .supports_autosuspend = 1,
1429 };
1430
1431 module_usb_driver(usblp_driver);
1432
1433 MODULE_AUTHOR(DRIVER_AUTHOR);
1434 MODULE_DESCRIPTION(DRIVER_DESC);
1435 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1436 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1437 MODULE_LICENSE("GPL");