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         kfree(usblp);
 449 }
 450
 451 static void usblp_unlink_urbs(struct usblp *usblp)
 452 {
 453         usb_kill_anchored_urbs(&usblp->urbs);
 454 }
 455
 456 static int usblp_release(struct inode *inode, struct file *file)
 457 {
 458         struct usblp *usblp = file->private_data;
 459
 460         usblp->flags &= ~LP_ABORT;
 461
 462         mutex_lock(&usblp_mutex);
 463         usblp->used = 0;
 464         if (usblp->present) {
 465                 usblp_unlink_urbs(usblp);
 466                 usb_autopm_put_interface(usblp->intf);
 467         } else          /* finish cleanup from disconnect */
 468                 usblp_cleanup(usblp);
 469         mutex_unlock(&usblp_mutex);
 470         return 0;
 471 }
 472
 473 /* No kernel lock - fine */
 474 static __poll_t usblp_poll(struct file *file, struct poll_table_struct *wait)
 475 {
 476         __poll_t ret;
 477         unsigned long flags;
 478
 479         struct usblp *usblp = file->private_data;
 480         /* Should we check file->f_mode & FMODE_WRITE before poll_wait()? */
 481         poll_wait(file, &usblp->rwait, wait);
 482         poll_wait(file, &usblp->wwait, wait);
 483         spin_lock_irqsave(&usblp->lock, flags);
 484         ret = ((usblp->bidir && usblp->rcomplete) ? EPOLLIN  | EPOLLRDNORM : 0) |
 485            ((usblp->no_paper || usblp->wcomplete) ? EPOLLOUT | EPOLLWRNORM : 0);
 486         spin_unlock_irqrestore(&usblp->lock, flags);
 487         return ret;
 488 }
 489
 490 static long usblp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 491 {
 492         struct usblp *usblp = file->private_data;
 493         int length, err, i;
 494         unsigned char newChannel;
 495         int status;
 496         int twoints[2];
 497         int retval = 0;
 498
 499         mutex_lock(&usblp->mut);
 500         if (!usblp->present) {
 501                 retval = -ENODEV;
 502                 goto done;
 503         }
 504
 505         dev_dbg(&usblp->intf->dev,
 506                 "usblp_ioctl: cmd=0x%x (%c nr=%d len=%d dir=%d)\n", cmd,
 507                 _IOC_TYPE(cmd), _IOC_NR(cmd), _IOC_SIZE(cmd), _IOC_DIR(cmd));
 508
 509         if (_IOC_TYPE(cmd) == 'P')      /* new-style ioctl number */
 510
 511                 switch (_IOC_NR(cmd)) {
 512
 513                 case IOCNR_GET_DEVICE_ID: /* get the DEVICE_ID string */
 514                         if (_IOC_DIR(cmd) != _IOC_READ) {
 515                                 retval = -EINVAL;
 516                                 goto done;
 517                         }
 518
 519                         length = usblp_cache_device_id_string(usblp);
 520                         if (length < 0) {
 521                                 retval = length;
 522                                 goto done;
 523                         }
 524                         if (length > _IOC_SIZE(cmd))
 525                                 length = _IOC_SIZE(cmd); /* truncate */
 526
 527                         if (copy_to_user((void __user *) arg,
 528                                         usblp->device_id_string,
 529                                         (unsigned long) length)) {
 530                                 retval = -EFAULT;
 531                                 goto done;
 532                         }
 533
 534                         break;
 535
 536                 case IOCNR_GET_PROTOCOLS:
 537                         if (_IOC_DIR(cmd) != _IOC_READ ||
 538                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 539                                 retval = -EINVAL;
 540                                 goto done;
 541                         }
 542
 543                         twoints[0] = usblp->current_protocol;
 544                         twoints[1] = 0;
 545                         for (i = USBLP_FIRST_PROTOCOL;
 546                              i <= USBLP_LAST_PROTOCOL; i++) {
 547                                 if (usblp->protocol[i].alt_setting >= 0)
 548                                         twoints[1] |= (1<<i);
 549                         }
 550
 551                         if (copy_to_user((void __user *)arg,
 552                                         (unsigned char *)twoints,
 553                                         sizeof(twoints))) {
 554                                 retval = -EFAULT;
 555                                 goto done;
 556                         }
 557
 558                         break;
 559
 560                 case IOCNR_SET_PROTOCOL:
 561                         if (_IOC_DIR(cmd) != _IOC_WRITE) {
 562                                 retval = -EINVAL;
 563                                 goto done;
 564                         }
 565
 566 #ifdef DEBUG
 567                         if (arg == -10) {
 568                                 usblp_dump(usblp);
 569                                 break;
 570                         }
 571 #endif
 572
 573                         usblp_unlink_urbs(usblp);
 574                         retval = usblp_set_protocol(usblp, arg);
 575                         if (retval < 0) {
 576                                 usblp_set_protocol(usblp,
 577                                         usblp->current_protocol);
 578                         }
 579                         break;
 580
 581                 case IOCNR_HP_SET_CHANNEL:
 582                         if (_IOC_DIR(cmd) != _IOC_WRITE ||
 583                             le16_to_cpu(usblp->dev->descriptor.idVendor) != 0x03F0 ||
 584                             usblp->quirks & USBLP_QUIRK_BIDIR) {
 585                                 retval = -EINVAL;
 586                                 goto done;
 587                         }
 588
 589                         err = usblp_hp_channel_change_request(usblp,
 590                                 arg, &newChannel);
 591                         if (err < 0) {
 592                                 dev_err(&usblp->dev->dev,
 593                                         "usblp%d: error = %d setting "
 594                                         "HP channel\n",
 595                                         usblp->minor, err);
 596                                 retval = -EIO;
 597                                 goto done;
 598                         }
 599
 600                         dev_dbg(&usblp->intf->dev,
 601                                 "usblp%d requested/got HP channel %ld/%d\n",
 602                                 usblp->minor, arg, newChannel);
 603                         break;
 604
 605                 case IOCNR_GET_BUS_ADDRESS:
 606                         if (_IOC_DIR(cmd) != _IOC_READ ||
 607                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 608                                 retval = -EINVAL;
 609                                 goto done;
 610                         }
 611
 612                         twoints[0] = usblp->dev->bus->busnum;
 613                         twoints[1] = usblp->dev->devnum;
 614                         if (copy_to_user((void __user *)arg,
 615                                         (unsigned char *)twoints,
 616                                         sizeof(twoints))) {
 617                                 retval = -EFAULT;
 618                                 goto done;
 619                         }
 620
 621                         dev_dbg(&usblp->intf->dev,
 622                                 "usblp%d is bus=%d, device=%d\n",
 623                                 usblp->minor, twoints[0], twoints[1]);
 624                         break;
 625
 626                 case IOCNR_GET_VID_PID:
 627                         if (_IOC_DIR(cmd) != _IOC_READ ||
 628                             _IOC_SIZE(cmd) < sizeof(twoints)) {
 629                                 retval = -EINVAL;
 630                                 goto done;
 631                         }
 632
 633                         twoints[0] = le16_to_cpu(usblp->dev->descriptor.idVendor);
 634                         twoints[1] = le16_to_cpu(usblp->dev->descriptor.idProduct);
 635                         if (copy_to_user((void __user *)arg,
 636                                         (unsigned char *)twoints,
 637                                         sizeof(twoints))) {
 638                                 retval = -EFAULT;
 639                                 goto done;
 640                         }
 641
 642                         dev_dbg(&usblp->intf->dev,
 643                                 "usblp%d is VID=0x%4.4X, PID=0x%4.4X\n",
 644                                 usblp->minor, twoints[0], twoints[1]);
 645                         break;
 646
 647                 case IOCNR_SOFT_RESET:
 648                         if (_IOC_DIR(cmd) != _IOC_NONE) {
 649                                 retval = -EINVAL;
 650                                 goto done;
 651                         }
 652                         retval = usblp_reset(usblp);
 653                         break;
 654                 default:
 655                         retval = -ENOTTY;
 656                 }
 657         else    /* old-style ioctl value */
 658                 switch (cmd) {
 659
 660                 case LPGETSTATUS:
 661                         retval = usblp_read_status(usblp, usblp->statusbuf);
 662                         if (retval) {
 663                                 printk_ratelimited(KERN_ERR "usblp%d:"
 664                                             "failed reading printer status (%d)\n",
 665                                             usblp->minor, retval);
 666                                 retval = -EIO;
 667                                 goto done;
 668                         }
 669                         status = *usblp->statusbuf;
 670                         if (copy_to_user((void __user *)arg, &status, sizeof(int)))
 671                                 retval = -EFAULT;
 672                         break;
 673
 674                 case LPABORT:
 675                         if (arg)
 676                                 usblp->flags |= LP_ABORT;
 677                         else
 678                                 usblp->flags &= ~LP_ABORT;
 679                         break;
 680
 681                 default:
 682                         retval = -ENOTTY;
 683                 }
 684
 685 done:
 686         mutex_unlock(&usblp->mut);
 687         return retval;
 688 }
 689
 690 static struct urb *usblp_new_writeurb(struct usblp *usblp, int transfer_length)
 691 {
 692         struct urb *urb;
 693         char *writebuf;
 694
 695         writebuf = kmalloc(transfer_length, GFP_KERNEL);
 696         if (writebuf == NULL)
 697                 return NULL;
 698         urb = usb_alloc_urb(0, GFP_KERNEL);
 699         if (urb == NULL) {
 700                 kfree(writebuf);
 701                 return NULL;
 702         }
 703
 704         usb_fill_bulk_urb(urb, usblp->dev,
 705                 usb_sndbulkpipe(usblp->dev,
 706                  usblp->protocol[usblp->current_protocol].epwrite->bEndpointAddress),
 707                 writebuf, transfer_length, usblp_bulk_write, usblp);
 708         urb->transfer_flags |= URB_FREE_BUFFER;
 709
 710         return urb;
 711 }
 712
 713 static ssize_t usblp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
 714 {
 715         struct usblp *usblp = file->private_data;
 716         struct urb *writeurb;
 717         int rv;
 718         int transfer_length;
 719         ssize_t writecount = 0;
 720
 721         if (mutex_lock_interruptible(&usblp->wmut)) {
 722                 rv = -EINTR;
 723                 goto raise_biglock;
 724         }
 725         if ((rv = usblp_wwait(usblp, !!(file->f_flags & O_NONBLOCK))) < 0)
 726                 goto raise_wait;
 727
 728         while (writecount < count) {
 729                 /*
 730                  * Step 1: Submit next block.
 731                  */
 732                 if ((transfer_length = count - writecount) > USBLP_BUF_SIZE)
 733                         transfer_length = USBLP_BUF_SIZE;
 734
 735                 rv = -ENOMEM;
 736                 writeurb = usblp_new_writeurb(usblp, transfer_length);
 737                 if (writeurb == NULL)
 738                         goto raise_urb;
 739                 usb_anchor_urb(writeurb, &usblp->urbs);
 740
 741                 if (copy_from_user(writeurb->transfer_buffer,
 742                                    buffer + writecount, transfer_length)) {
 743                         rv = -EFAULT;
 744                         goto raise_badaddr;
 745                 }
 746
 747                 spin_lock_irq(&usblp->lock);
 748                 usblp->wcomplete = 0;
 749                 spin_unlock_irq(&usblp->lock);
 750                 if ((rv = usb_submit_urb(writeurb, GFP_KERNEL)) < 0) {
 751                         usblp->wstatus = 0;
 752                         spin_lock_irq(&usblp->lock);
 753                         usblp->no_paper = 0;
 754                         usblp->wcomplete = 1;
 755                         wake_up(&usblp->wwait);
 756                         spin_unlock_irq(&usblp->lock);
 757                         if (rv != -ENOMEM)
 758                                 rv = -EIO;
 759                         goto raise_submit;
 760                 }
 761
 762                 /*
 763                  * Step 2: Wait for transfer to end, collect results.
 764                  */
 765                 rv = usblp_wwait(usblp, !!(file->f_flags&O_NONBLOCK));
 766                 if (rv < 0) {
 767                         if (rv == -EAGAIN) {
 768                                 /* Presume that it's going to complete well. */
 769                                 writecount += transfer_length;
 770                         }
 771                         if (rv == -ENOSPC) {
 772                                 spin_lock_irq(&usblp->lock);
 773                                 usblp->no_paper = 1;    /* Mark for poll(2) */
 774                                 spin_unlock_irq(&usblp->lock);
 775                                 writecount += transfer_length;
 776                         }
 777                         /* Leave URB dangling, to be cleaned on close. */
 778                         goto collect_error;
 779                 }
 780
 781                 if (usblp->wstatus < 0) {
 782                         rv = -EIO;
 783                         goto collect_error;
 784                 }
 785                 /*
 786                  * This is critical: it must be our URB, not other writer's.
 787                  * The wmut exists mainly to cover us here.
 788                  */
 789                 writecount += usblp->wstatus;
 790         }
 791
 792         mutex_unlock(&usblp->wmut);
 793         return writecount;
 794
 795 raise_submit:
 796 raise_badaddr:
 797         usb_unanchor_urb(writeurb);
 798         usb_free_urb(writeurb);
 799 raise_urb:
 800 raise_wait:
 801 collect_error:          /* Out of raise sequence */
 802         mutex_unlock(&usblp->wmut);
 803 raise_biglock:
 804         return writecount ? writecount : rv;
 805 }
 806
 807 /*
 808  * Notice that we fail to restart in a few cases: on EFAULT, on restart
 809  * error, etc. This is the historical behaviour. In all such cases we return
 810  * EIO, and applications loop in order to get the new read going.
 811  */
 812 static ssize_t usblp_read(struct file *file, char __user *buffer, size_t len, loff_t *ppos)
 813 {
 814         struct usblp *usblp = file->private_data;
 815         ssize_t count;
 816         ssize_t avail;
 817         int rv;
 818
 819         if (!usblp->bidir)
 820                 return -EINVAL;
 821
 822         rv = usblp_rwait_and_lock(usblp, !!(file->f_flags & O_NONBLOCK));
 823         if (rv < 0)
 824                 return rv;
 825
 826         if ((avail = usblp->rstatus) < 0) {
 827                 printk(KERN_ERR "usblp%d: error %d reading from printer\n",
 828                     usblp->minor, (int)avail);
 829                 usblp_submit_read(usblp);
 830                 count = -EIO;
 831                 goto done;
 832         }
 833
 834         count = len < avail - usblp->readcount ? len : avail - usblp->readcount;
 835         if (count != 0 &&
 836             copy_to_user(buffer, usblp->readbuf + usblp->readcount, count)) {
 837                 count = -EFAULT;
 838                 goto done;
 839         }
 840
 841         if ((usblp->readcount += count) == avail) {
 842                 if (usblp_submit_read(usblp) < 0) {
 843                         /* We don't want to leak USB return codes into errno. */
 844                         if (count == 0)
 845                                 count = -EIO;
 846                         goto done;
 847                 }
 848         }
 849
 850 done:
 851         mutex_unlock(&usblp->mut);
 852         return count;
 853 }
 854
 855 /*
 856  * Wait for the write path to come idle.
 857  * This is called under the ->wmut, so the idle path stays idle.
 858  *
 859  * Our write path has a peculiar property: it does not buffer like a tty,
 860  * but waits for the write to succeed. This allows our ->release to bug out
 861  * without waiting for writes to drain. But it obviously does not work
 862  * when O_NONBLOCK is set. So, applications setting O_NONBLOCK must use
 863  * select(2) or poll(2) to wait for the buffer to drain before closing.
 864  * Alternatively, set blocking mode with fcntl and issue a zero-size write.
 865  */
 866 static int usblp_wwait(struct usblp *usblp, int nonblock)
 867 {
 868         DECLARE_WAITQUEUE(waita, current);
 869         int rc;
 870         int err = 0;
 871
 872         add_wait_queue(&usblp->wwait, &waita);
 873         for (;;) {
 874                 if (mutex_lock_interruptible(&usblp->mut)) {
 875                         rc = -EINTR;
 876                         break;
 877                 }
 878                 set_current_state(TASK_INTERRUPTIBLE);
 879                 rc = usblp_wtest(usblp, nonblock);
 880                 mutex_unlock(&usblp->mut);
 881                 if (rc <= 0)
 882                         break;
 883
 884                 if (schedule_timeout(msecs_to_jiffies(1500)) == 0) {
 885                         if (usblp->flags & LP_ABORT) {
 886                                 err = usblp_check_status(usblp, err);
 887                                 if (err == 1) { /* Paper out */
 888                                         rc = -ENOSPC;
 889                                         break;
 890                                 }
 891                         } else {
 892                                 /* Prod the printer, Gentoo#251237. */
 893                                 mutex_lock(&usblp->mut);
 894                                 usblp_read_status(usblp, usblp->statusbuf);
 895                                 mutex_unlock(&usblp->mut);
 896                         }
 897                 }
 898         }
 899         set_current_state(TASK_RUNNING);
 900         remove_wait_queue(&usblp->wwait, &waita);
 901         return rc;
 902 }
 903
 904 static int usblp_wtest(struct usblp *usblp, int nonblock)
 905 {
 906         unsigned long flags;
 907
 908         if (!usblp->present)
 909                 return -ENODEV;
 910         if (signal_pending(current))
 911                 return -EINTR;
 912         spin_lock_irqsave(&usblp->lock, flags);
 913         if (usblp->wcomplete) {
 914                 spin_unlock_irqrestore(&usblp->lock, flags);
 915                 return 0;
 916         }
 917         spin_unlock_irqrestore(&usblp->lock, flags);
 918         if (nonblock)
 919                 return -EAGAIN;
 920         return 1;
 921 }
 922
 923 /*
 924  * Wait for read bytes to become available. This probably should have been
 925  * called usblp_r_lock_and_wait(), because we lock first. But it's a traditional
 926  * name for functions which lock and return.
 927  *
 928  * We do not use wait_event_interruptible because it makes locking iffy.
 929  */
 930 static int usblp_rwait_and_lock(struct usblp *usblp, int nonblock)
 931 {
 932         DECLARE_WAITQUEUE(waita, current);
 933         int rc;
 934
 935         add_wait_queue(&usblp->rwait, &waita);
 936         for (;;) {
 937                 if (mutex_lock_interruptible(&usblp->mut)) {
 938                         rc = -EINTR;
 939                         break;
 940                 }
 941                 set_current_state(TASK_INTERRUPTIBLE);
 942                 if ((rc = usblp_rtest(usblp, nonblock)) < 0) {
 943                         mutex_unlock(&usblp->mut);
 944                         break;
 945                 }
 946                 if (rc == 0)    /* Keep it locked */
 947                         break;
 948                 mutex_unlock(&usblp->mut);
 949                 schedule();
 950         }
 951         set_current_state(TASK_RUNNING);
 952         remove_wait_queue(&usblp->rwait, &waita);
 953         return rc;
 954 }
 955
 956 static int usblp_rtest(struct usblp *usblp, int nonblock)
 957 {
 958         unsigned long flags;
 959
 960         if (!usblp->present)
 961                 return -ENODEV;
 962         if (signal_pending(current))
 963                 return -EINTR;
 964         spin_lock_irqsave(&usblp->lock, flags);
 965         if (usblp->rcomplete) {
 966                 spin_unlock_irqrestore(&usblp->lock, flags);
 967                 return 0;
 968         }
 969         spin_unlock_irqrestore(&usblp->lock, flags);
 970         if (nonblock)
 971                 return -EAGAIN;
 972         return 1;
 973 }
 974
 975 /*
 976  * Please check ->bidir and other such things outside for now.
 977  */
 978 static int usblp_submit_read(struct usblp *usblp)
 979 {
 980         struct urb *urb;
 981         unsigned long flags;
 982         int rc;
 983
 984         rc = -ENOMEM;
 985         urb = usb_alloc_urb(0, GFP_KERNEL);
 986         if (urb == NULL)
 987                 goto raise_urb;
 988
 989         usb_fill_bulk_urb(urb, usblp->dev,
 990                 usb_rcvbulkpipe(usblp->dev,
 991                   usblp->protocol[usblp->current_protocol].epread->bEndpointAddress),
 992                 usblp->readbuf, USBLP_BUF_SIZE_IN,
 993                 usblp_bulk_read, usblp);
 994         usb_anchor_urb(urb, &usblp->urbs);
 995
 996         spin_lock_irqsave(&usblp->lock, flags);
 997         usblp->readcount = 0; /* XXX Why here? */
 998         usblp->rcomplete = 0;
 999         spin_unlock_irqrestore(&usblp->lock, flags);
1000         if ((rc = usb_submit_urb(urb, GFP_KERNEL)) < 0) {
1001                 dev_dbg(&usblp->intf->dev, "error submitting urb (%d)\n", rc);
1002                 spin_lock_irqsave(&usblp->lock, flags);
1003                 usblp->rstatus = rc;
1004                 usblp->rcomplete = 1;
1005                 spin_unlock_irqrestore(&usblp->lock, flags);
1006                 goto raise_submit;
1007         }
1008
1009         return 0;
1010
1011 raise_submit:
1012         usb_unanchor_urb(urb);
1013         usb_free_urb(urb);
1014 raise_urb:
1015         return rc;
1016 }
1017
1018 /*
1019  * Checks for printers that have quirks, such as requiring unidirectional
1020  * communication but reporting bidirectional; currently some HP printers
1021  * have this flaw (HP 810, 880, 895, etc.), or needing an init string
1022  * sent at each open (like some Epsons).
1023  * Returns 1 if found, 0 if not found.
1024  *
1025  * HP recommended that we use the bidirectional interface but
1026  * don't attempt any bulk IN transfers from the IN endpoint.
1027  * Here's some more detail on the problem:
1028  * The problem is not that it isn't bidirectional though. The problem
1029  * is that if you request a device ID, or status information, while
1030  * the buffers are full, the return data will end up in the print data
1031  * buffer. For example if you make sure you never request the device ID
1032  * while you are sending print data, and you don't try to query the
1033  * printer status every couple of milliseconds, you will probably be OK.
1034  */
1035 static unsigned int usblp_quirks(__u16 vendor, __u16 product)
1036 {
1037         int i;
1038
1039         for (i = 0; quirk_printers[i].vendorId; i++) {
1040                 if (vendor == quirk_printers[i].vendorId &&
1041                     product == quirk_printers[i].productId)
1042                         return quirk_printers[i].quirks;
1043         }
1044         return 0;
1045 }
1046
1047 static const struct file_operations usblp_fops = {
1048         .owner =        THIS_MODULE,
1049         .read =         usblp_read,
1050         .write =        usblp_write,
1051         .poll =         usblp_poll,
1052         .unlocked_ioctl =       usblp_ioctl,
1053         .compat_ioctl =         usblp_ioctl,
1054         .open =         usblp_open,
1055         .release =      usblp_release,
1056         .llseek =       noop_llseek,
1057 };
1058
1059 static char *usblp_devnode(struct device *dev, umode_t *mode)
1060 {
1061         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
1062 }
1063
1064 static struct usb_class_driver usblp_class = {
1065         .name =         "lp%d",
1066         .devnode =      usblp_devnode,
1067         .fops =         &usblp_fops,
1068         .minor_base =   USBLP_MINOR_BASE,
1069 };
1070
1071 static ssize_t ieee1284_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1072 {
1073         struct usb_interface *intf = to_usb_interface(dev);
1074         struct usblp *usblp = usb_get_intfdata(intf);
1075
1076         if (usblp->device_id_string[0] == 0 &&
1077             usblp->device_id_string[1] == 0)
1078                 return 0;
1079
1080         return sprintf(buf, "%s", usblp->device_id_string+2);
1081 }
1082
1083 static DEVICE_ATTR_RO(ieee1284_id);
1084
1085 static int usblp_probe(struct usb_interface *intf,
1086                        const struct usb_device_id *id)
1087 {
1088         struct usb_device *dev = interface_to_usbdev(intf);
1089         struct usblp *usblp;
1090         int protocol;
1091         int retval;
1092
1093         /* Malloc and start initializing usblp structure so we can use it
1094          * directly. */
1095         usblp = kzalloc(sizeof(struct usblp), GFP_KERNEL);
1096         if (!usblp) {
1097                 retval = -ENOMEM;
1098                 goto abort_ret;
1099         }
1100         usblp->dev = dev;
1101         mutex_init(&usblp->wmut);
1102         mutex_init(&usblp->mut);
1103         spin_lock_init(&usblp->lock);
1104         init_waitqueue_head(&usblp->rwait);
1105         init_waitqueue_head(&usblp->wwait);
1106         init_usb_anchor(&usblp->urbs);
1107         usblp->ifnum = intf->cur_altsetting->desc.bInterfaceNumber;
1108         usblp->intf = intf;
1109
1110         /* Malloc device ID string buffer to the largest expected length,
1111          * since we can re-query it on an ioctl and a dynamic string
1112          * could change in length. */
1113         if (!(usblp->device_id_string = kmalloc(USBLP_DEVICE_ID_SIZE, GFP_KERNEL))) {
1114                 retval = -ENOMEM;
1115                 goto abort;
1116         }
1117
1118         /*
1119          * Allocate read buffer. We somewhat wastefully
1120          * malloc both regardless of bidirectionality, because the
1121          * alternate setting can be changed later via an ioctl.
1122          */
1123         if (!(usblp->readbuf = kmalloc(USBLP_BUF_SIZE_IN, GFP_KERNEL))) {
1124                 retval = -ENOMEM;
1125                 goto abort;
1126         }
1127
1128         /* Allocate buffer for printer status */
1129         usblp->statusbuf = kmalloc(STATUS_BUF_SIZE, GFP_KERNEL);
1130         if (!usblp->statusbuf) {
1131                 retval = -ENOMEM;
1132                 goto abort;
1133         }
1134
1135         /* Lookup quirks for this printer. */
1136         usblp->quirks = usblp_quirks(
1137                 le16_to_cpu(dev->descriptor.idVendor),
1138                 le16_to_cpu(dev->descriptor.idProduct));
1139
1140         /* Analyze and pick initial alternate settings and endpoints. */
1141         protocol = usblp_select_alts(usblp);
1142         if (protocol < 0) {
1143                 dev_dbg(&intf->dev,
1144                         "incompatible printer-class device 0x%4.4X/0x%4.4X\n",
1145                         le16_to_cpu(dev->descriptor.idVendor),
1146                         le16_to_cpu(dev->descriptor.idProduct));
1147                 retval = -ENODEV;
1148                 goto abort;
1149         }
1150
1151         /* Setup the selected alternate setting and endpoints. */
1152         if (usblp_set_protocol(usblp, protocol) < 0) {
1153                 retval = -ENODEV;       /* ->probe isn't ->ioctl */
1154                 goto abort;
1155         }
1156
1157         /* Retrieve and store the device ID string. */
1158         usblp_cache_device_id_string(usblp);
1159         retval = device_create_file(&intf->dev, &dev_attr_ieee1284_id);
1160         if (retval)
1161                 goto abort_intfdata;
1162
1163 #ifdef DEBUG
1164         usblp_check_status(usblp, 0);
1165 #endif
1166
1167         usb_set_intfdata(intf, usblp);
1168
1169         usblp->present = 1;
1170
1171         retval = usb_register_dev(intf, &usblp_class);
1172         if (retval) {
1173                 dev_err(&intf->dev,
1174                         "usblp: Not able to get a minor (base %u, slice default): %d\n",
1175                         USBLP_MINOR_BASE, retval);
1176                 goto abort_intfdata;
1177         }
1178         usblp->minor = intf->minor;
1179         dev_info(&intf->dev,
1180                 "usblp%d: USB %sdirectional printer dev %d if %d alt %d proto %d vid 0x%4.4X pid 0x%4.4X\n",
1181                 usblp->minor, usblp->bidir ? "Bi" : "Uni", dev->devnum,
1182                 usblp->ifnum,
1183                 usblp->protocol[usblp->current_protocol].alt_setting,
1184                 usblp->current_protocol,
1185                 le16_to_cpu(usblp->dev->descriptor.idVendor),
1186                 le16_to_cpu(usblp->dev->descriptor.idProduct));
1187
1188         return 0;
1189
1190 abort_intfdata:
1191         usb_set_intfdata(intf, NULL);
1192         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1193 abort:
1194         kfree(usblp->readbuf);
1195         kfree(usblp->statusbuf);
1196         kfree(usblp->device_id_string);
1197         kfree(usblp);
1198 abort_ret:
1199         return retval;
1200 }
1201
1202 /*
1203  * We are a "new" style driver with usb_device_id table,
1204  * but our requirements are too intricate for simple match to handle.
1205  *
1206  * The "proto_bias" option may be used to specify the preferred protocol
1207  * for all USB printers (1=USB_CLASS_PRINTER/1/1, 2=USB_CLASS_PRINTER/1/2,
1208  * 3=USB_CLASS_PRINTER/1/3).  If the device supports the preferred protocol,
1209  * then we bind to it.
1210  *
1211  * The best interface for us is USB_CLASS_PRINTER/1/2, because it
1212  * is compatible with a stream of characters. If we find it, we bind to it.
1213  *
1214  * Note that the people from hpoj.sourceforge.net need to be able to
1215  * bind to USB_CLASS_PRINTER/1/3 (MLC/1284.4), so we provide them ioctls
1216  * for this purpose.
1217  *
1218  * Failing USB_CLASS_PRINTER/1/2, we look for USB_CLASS_PRINTER/1/3,
1219  * even though it's probably not stream-compatible, because this matches
1220  * the behaviour of the old code.
1221  *
1222  * If nothing else, we bind to USB_CLASS_PRINTER/1/1
1223  * - the unidirectional interface.
1224  */
1225 static int usblp_select_alts(struct usblp *usblp)
1226 {
1227         struct usb_interface *if_alt;
1228         struct usb_host_interface *ifd;
1229         struct usb_endpoint_descriptor *epwrite, *epread;
1230         int p, i;
1231         int res;
1232
1233         if_alt = usblp->intf;
1234
1235         for (p = 0; p < USBLP_MAX_PROTOCOLS; p++)
1236                 usblp->protocol[p].alt_setting = -1;
1237
1238         /* Find out what we have. */
1239         for (i = 0; i < if_alt->num_altsetting; i++) {
1240                 ifd = &if_alt->altsetting[i];
1241
1242                 if (ifd->desc.bInterfaceClass != USB_CLASS_PRINTER ||
1243                     ifd->desc.bInterfaceSubClass != 1)
1244                         if (!(usblp->quirks & USBLP_QUIRK_BAD_CLASS))
1245                                 continue;
1246
1247                 if (ifd->desc.bInterfaceProtocol < USBLP_FIRST_PROTOCOL ||
1248                     ifd->desc.bInterfaceProtocol > USBLP_LAST_PROTOCOL)
1249                         continue;
1250
1251                 /* Look for the expected bulk endpoints. */
1252                 if (ifd->desc.bInterfaceProtocol > 1) {
1253                         res = usb_find_common_endpoints(ifd,
1254                                         &epread, &epwrite, NULL, NULL);
1255                 } else {
1256                         epread = NULL;
1257                         res = usb_find_bulk_out_endpoint(ifd, &epwrite);
1258                 }
1259
1260                 /* Ignore buggy hardware without the right endpoints. */
1261                 if (res)
1262                         continue;
1263
1264                 /* Turn off reads for buggy bidirectional printers. */
1265                 if (usblp->quirks & USBLP_QUIRK_BIDIR) {
1266                         printk(KERN_INFO "usblp%d: Disabling reads from "
1267                             "problematic bidirectional printer\n",
1268                             usblp->minor);
1269                         epread = NULL;
1270                 }
1271
1272                 usblp->protocol[ifd->desc.bInterfaceProtocol].alt_setting =
1273                                 ifd->desc.bAlternateSetting;
1274                 usblp->protocol[ifd->desc.bInterfaceProtocol].epwrite = epwrite;
1275                 usblp->protocol[ifd->desc.bInterfaceProtocol].epread = epread;
1276         }
1277
1278         /* If our requested protocol is supported, then use it. */
1279         if (proto_bias >= USBLP_FIRST_PROTOCOL &&
1280             proto_bias <= USBLP_LAST_PROTOCOL &&
1281             usblp->protocol[proto_bias].alt_setting != -1)
1282                 return proto_bias;
1283
1284         /* Ordering is important here. */
1285         if (usblp->protocol[2].alt_setting != -1)
1286                 return 2;
1287         if (usblp->protocol[1].alt_setting != -1)
1288                 return 1;
1289         if (usblp->protocol[3].alt_setting != -1)
1290                 return 3;
1291
1292         /* If nothing is available, then don't bind to this device. */
1293         return -1;
1294 }
1295
1296 static int usblp_set_protocol(struct usblp *usblp, int protocol)
1297 {
1298         int r, alts;
1299
1300         if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL)
1301                 return -EINVAL;
1302
1303         alts = usblp->protocol[protocol].alt_setting;
1304         if (alts < 0)
1305                 return -EINVAL;
1306         r = usb_set_interface(usblp->dev, usblp->ifnum, alts);
1307         if (r < 0) {
1308                 printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n",
1309                         alts, usblp->ifnum);
1310                 return r;
1311         }
1312
1313         usblp->bidir = (usblp->protocol[protocol].epread != NULL);
1314         usblp->current_protocol = protocol;
1315         dev_dbg(&usblp->intf->dev, "usblp%d set protocol %d\n",
1316                 usblp->minor, protocol);
1317         return 0;
1318 }
1319
1320 /* Retrieves and caches device ID string.
1321  * Returns length, including length bytes but not null terminator.
1322  * On error, returns a negative errno value. */
1323 static int usblp_cache_device_id_string(struct usblp *usblp)
1324 {
1325         int err, length;
1326
1327         err = usblp_get_id(usblp, 0, usblp->device_id_string, USBLP_DEVICE_ID_SIZE - 1);
1328         if (err < 0) {
1329                 dev_dbg(&usblp->intf->dev,
1330                         "usblp%d: error = %d reading IEEE-1284 Device ID string\n",
1331                         usblp->minor, err);
1332                 usblp->device_id_string[0] = usblp->device_id_string[1] = '\0';
1333                 return -EIO;
1334         }
1335
1336         /* First two bytes are length in big-endian.
1337          * They count themselves, and we copy them into
1338          * the user's buffer. */
1339         length = be16_to_cpu(*((__be16 *)usblp->device_id_string));
1340         if (length < 2)
1341                 length = 2;
1342         else if (length >= USBLP_DEVICE_ID_SIZE)
1343                 length = USBLP_DEVICE_ID_SIZE - 1;
1344         usblp->device_id_string[length] = '\0';
1345
1346         dev_dbg(&usblp->intf->dev, "usblp%d Device ID string [len=%d]=\"%s\"\n",
1347                 usblp->minor, length, &usblp->device_id_string[2]);
1348
1349         return length;
1350 }
1351
1352 static void usblp_disconnect(struct usb_interface *intf)
1353 {
1354         struct usblp *usblp = usb_get_intfdata(intf);
1355
1356         usb_deregister_dev(intf, &usblp_class);
1357
1358         if (!usblp || !usblp->dev) {
1359                 dev_err(&intf->dev, "bogus disconnect\n");
1360                 BUG();
1361         }
1362
1363         device_remove_file(&intf->dev, &dev_attr_ieee1284_id);
1364
1365         mutex_lock(&usblp_mutex);
1366         mutex_lock(&usblp->mut);
1367         usblp->present = 0;
1368         wake_up(&usblp->wwait);
1369         wake_up(&usblp->rwait);
1370         usb_set_intfdata(intf, NULL);
1371
1372         usblp_unlink_urbs(usblp);
1373         mutex_unlock(&usblp->mut);
1374
1375         if (!usblp->used)
1376                 usblp_cleanup(usblp);
1377         mutex_unlock(&usblp_mutex);
1378 }
1379
1380 static int usblp_suspend(struct usb_interface *intf, pm_message_t message)
1381 {
1382         struct usblp *usblp = usb_get_intfdata(intf);
1383
1384         usblp_unlink_urbs(usblp);
1385 #if 0 /* XXX Do we want this? What if someone is reading, should we fail? */
1386         /* not strictly necessary, but just in case */
1387         wake_up(&usblp->wwait);
1388         wake_up(&usblp->rwait);
1389 #endif
1390
1391         return 0;
1392 }
1393
1394 static int usblp_resume(struct usb_interface *intf)
1395 {
1396         struct usblp *usblp = usb_get_intfdata(intf);
1397         int r;
1398
1399         r = handle_bidir(usblp);
1400
1401         return r;
1402 }
1403
1404 static const struct usb_device_id usblp_ids[] = {
1405         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 1) },
1406         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 2) },
1407         { USB_DEVICE_INFO(USB_CLASS_PRINTER, 1, 3) },
1408         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 1) },
1409         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 2) },
1410         { USB_INTERFACE_INFO(USB_CLASS_PRINTER, 1, 3) },
1411         { USB_DEVICE(0x04b8, 0x0202) }, /* Seiko Epson Receipt Printer M129C */
1412         { }                                             /* Terminating entry */
1413 };
1414
1415 MODULE_DEVICE_TABLE(usb, usblp_ids);
1416
1417 static struct usb_driver usblp_driver = {
1418         .name =         "usblp",
1419         .probe =        usblp_probe,
1420         .disconnect =   usblp_disconnect,
1421         .suspend =      usblp_suspend,
1422         .resume =       usblp_resume,
1423         .id_table =     usblp_ids,
1424         .supports_autosuspend = 1,
1425 };
1426
1427 module_usb_driver(usblp_driver);
1428
1429 MODULE_AUTHOR(DRIVER_AUTHOR);
1430 MODULE_DESCRIPTION(DRIVER_DESC);
1431 module_param(proto_bias, int, S_IRUGO | S_IWUSR);
1432 MODULE_PARM_DESC(proto_bias, "Favourite protocol number");
1433 MODULE_LICENSE("GPL");