Pileus Git - ~andy/linux/blob - drivers/usb/gadget/printer.c

   1 /*
   2  * printer.c -- Printer gadget driver
   3  *
   4  * Copyright (C) 2003-2005 David Brownell
   5  * Copyright (C) 2006 Craig W. Nadler
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/delay.h>
  16 #include <linux/ioport.h>
  17 #include <linux/sched.h>
  18 #include <linux/slab.h>
  19 #include <linux/mutex.h>
  20 #include <linux/errno.h>
  21 #include <linux/init.h>
  22 #include <linux/timer.h>
  23 #include <linux/list.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/utsname.h>
  26 #include <linux/device.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/fs.h>
  29 #include <linux/poll.h>
  30 #include <linux/types.h>
  31 #include <linux/ctype.h>
  32 #include <linux/cdev.h>
  33
  34 #include <asm/byteorder.h>
  35 #include <linux/io.h>
  36 #include <linux/irq.h>
  37 #include <linux/uaccess.h>
  38 #include <asm/unaligned.h>
  39
  40 #include <linux/usb/ch9.h>
  41 #include <linux/usb/gadget.h>
  42 #include <linux/usb/g_printer.h>
  43
  44 #include "gadget_chips.h"
  45
  46
  47 /*
  48  * Kbuild is not very cooperative with respect to linking separately
  49  * compiled library objects into one module.  So for now we won't use
  50  * separate compilation ... ensuring init/exit sections work to shrink
  51  * the runtime footprint, and giving us at least some parts of what
  52  * a "gcc --combine ... part1.c part2.c part3.c ... " build would.
  53  */
  54 #include "composite.c"
  55
  56 /*-------------------------------------------------------------------------*/
  57 USB_GADGET_COMPOSITE_OPTIONS();
  58
  59 #define DRIVER_DESC             "Printer Gadget"
  60 #define DRIVER_VERSION          "2007 OCT 06"
  61
  62 static DEFINE_MUTEX(printer_mutex);
  63 static const char shortname [] = "printer";
  64 static const char driver_desc [] = DRIVER_DESC;
  65
  66 static dev_t g_printer_devno;
  67
  68 static struct class *usb_gadget_class;
  69
  70 /*-------------------------------------------------------------------------*/
  71
  72 struct printer_dev {
  73         spinlock_t              lock;           /* lock this structure */
  74         /* lock buffer lists during read/write calls */
  75         struct mutex            lock_printer_io;
  76         struct usb_gadget       *gadget;
  77         s8                      interface;
  78         struct usb_ep           *in_ep, *out_ep;
  79
  80         struct list_head        rx_reqs;        /* List of free RX structs */
  81         struct list_head        rx_reqs_active; /* List of Active RX xfers */
  82         struct list_head        rx_buffers;     /* List of completed xfers */
  83         /* wait until there is data to be read. */
  84         wait_queue_head_t       rx_wait;
  85         struct list_head        tx_reqs;        /* List of free TX structs */
  86         struct list_head        tx_reqs_active; /* List of Active TX xfers */
  87         /* Wait until there are write buffers available to use. */
  88         wait_queue_head_t       tx_wait;
  89         /* Wait until all write buffers have been sent. */
  90         wait_queue_head_t       tx_flush_wait;
  91         struct usb_request      *current_rx_req;
  92         size_t                  current_rx_bytes;
  93         u8                      *current_rx_buf;
  94         u8                      printer_status;
  95         u8                      reset_printer;
  96         struct cdev             printer_cdev;
  97         struct device           *pdev;
  98         u8                      printer_cdev_open;
  99         wait_queue_head_t       wait;
 100         struct usb_function     function;
 101 };
 102
 103 static struct printer_dev usb_printer_gadget;
 104
 105 /*-------------------------------------------------------------------------*/
 106
 107 /* DO NOT REUSE THESE IDs with a protocol-incompatible driver!!  Ever!!
 108  * Instead:  allocate your own, using normal USB-IF procedures.
 109  */
 110
 111 /* Thanks to NetChip Technologies for donating this product ID.
 112  */
 113 #define PRINTER_VENDOR_NUM      0x0525          /* NetChip */
 114 #define PRINTER_PRODUCT_NUM     0xa4a8          /* Linux-USB Printer Gadget */
 115
 116 /* Some systems will want different product identifiers published in the
 117  * device descriptor, either numbers or strings or both.  These string
 118  * parameters are in UTF-8 (superset of ASCII's 7 bit characters).
 119  */
 120
 121 static char *iSerialNum;
 122 module_param(iSerialNum, charp, S_IRUGO);
 123 MODULE_PARM_DESC(iSerialNum, "1");
 124
 125 static char *iPNPstring;
 126 module_param(iPNPstring, charp, S_IRUGO);
 127 MODULE_PARM_DESC(iPNPstring, "MFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;");
 128
 129 /* Number of requests to allocate per endpoint, not used for ep0. */
 130 static unsigned qlen = 10;
 131 module_param(qlen, uint, S_IRUGO|S_IWUSR);
 132
 133 #define QLEN    qlen
 134
 135 /*-------------------------------------------------------------------------*/
 136
 137 /*
 138  * DESCRIPTORS ... most are static, but strings and (full) configuration
 139  * descriptors are built on demand.
 140  */
 141
 142 #define STRING_MANUFACTURER             0
 143 #define STRING_PRODUCT                  1
 144 #define STRING_SERIALNUM                2
 145
 146 /* holds our biggest descriptor */
 147 #define USB_DESC_BUFSIZE                256
 148 #define USB_BUFSIZE                     8192
 149
 150 static struct usb_device_descriptor device_desc = {
 151         .bLength =              sizeof device_desc,
 152         .bDescriptorType =      USB_DT_DEVICE,
 153         .bcdUSB =               cpu_to_le16(0x0200),
 154         .bDeviceClass =         USB_CLASS_PER_INTERFACE,
 155         .bDeviceSubClass =      0,
 156         .bDeviceProtocol =      0,
 157         .idVendor =             cpu_to_le16(PRINTER_VENDOR_NUM),
 158         .idProduct =            cpu_to_le16(PRINTER_PRODUCT_NUM),
 159         .bNumConfigurations =   1
 160 };
 161
 162 static struct usb_interface_descriptor intf_desc = {
 163         .bLength =              sizeof intf_desc,
 164         .bDescriptorType =      USB_DT_INTERFACE,
 165         .bNumEndpoints =        2,
 166         .bInterfaceClass =      USB_CLASS_PRINTER,
 167         .bInterfaceSubClass =   1,      /* Printer Sub-Class */
 168         .bInterfaceProtocol =   2,      /* Bi-Directional */
 169         .iInterface =           0
 170 };
 171
 172 static struct usb_endpoint_descriptor fs_ep_in_desc = {
 173         .bLength =              USB_DT_ENDPOINT_SIZE,
 174         .bDescriptorType =      USB_DT_ENDPOINT,
 175         .bEndpointAddress =     USB_DIR_IN,
 176         .bmAttributes =         USB_ENDPOINT_XFER_BULK
 177 };
 178
 179 static struct usb_endpoint_descriptor fs_ep_out_desc = {
 180         .bLength =              USB_DT_ENDPOINT_SIZE,
 181         .bDescriptorType =      USB_DT_ENDPOINT,
 182         .bEndpointAddress =     USB_DIR_OUT,
 183         .bmAttributes =         USB_ENDPOINT_XFER_BULK
 184 };
 185
 186 static struct usb_descriptor_header *fs_printer_function[] = {
 187         (struct usb_descriptor_header *) &intf_desc,
 188         (struct usb_descriptor_header *) &fs_ep_in_desc,
 189         (struct usb_descriptor_header *) &fs_ep_out_desc,
 190         NULL
 191 };
 192
 193 /*
 194  * usb 2.0 devices need to expose both high speed and full speed
 195  * descriptors, unless they only run at full speed.
 196  */
 197
 198 static struct usb_endpoint_descriptor hs_ep_in_desc = {
 199         .bLength =              USB_DT_ENDPOINT_SIZE,
 200         .bDescriptorType =      USB_DT_ENDPOINT,
 201         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 202         .wMaxPacketSize =       cpu_to_le16(512)
 203 };
 204
 205 static struct usb_endpoint_descriptor hs_ep_out_desc = {
 206         .bLength =              USB_DT_ENDPOINT_SIZE,
 207         .bDescriptorType =      USB_DT_ENDPOINT,
 208         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 209         .wMaxPacketSize =       cpu_to_le16(512)
 210 };
 211
 212 static struct usb_qualifier_descriptor dev_qualifier = {
 213         .bLength =              sizeof dev_qualifier,
 214         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
 215         .bcdUSB =               cpu_to_le16(0x0200),
 216         .bDeviceClass =         USB_CLASS_PRINTER,
 217         .bNumConfigurations =   1
 218 };
 219
 220 static struct usb_descriptor_header *hs_printer_function[] = {
 221         (struct usb_descriptor_header *) &intf_desc,
 222         (struct usb_descriptor_header *) &hs_ep_in_desc,
 223         (struct usb_descriptor_header *) &hs_ep_out_desc,
 224         NULL
 225 };
 226
 227 static struct usb_otg_descriptor otg_descriptor = {
 228         .bLength =              sizeof otg_descriptor,
 229         .bDescriptorType =      USB_DT_OTG,
 230         .bmAttributes =         USB_OTG_SRP,
 231 };
 232
 233 static const struct usb_descriptor_header *otg_desc[] = {
 234         (struct usb_descriptor_header *) &otg_descriptor,
 235         NULL,
 236 };
 237
 238 /* maxpacket and other transfer characteristics vary by speed. */
 239 #define ep_desc(g, hs, fs) (((g)->speed == USB_SPEED_HIGH)?(hs):(fs))
 240
 241 /*-------------------------------------------------------------------------*/
 242
 243 /* descriptors that are built on-demand */
 244
 245 static char                             manufacturer [50];
 246 static char                             product_desc [40] = DRIVER_DESC;
 247 static char                             serial_num [40] = "1";
 248 static char                             pnp_string [1024] =
 249         "XXMFG:linux;MDL:g_printer;CLS:PRINTER;SN:1;";
 250
 251 /* static strings, in UTF-8 */
 252 static struct usb_string                strings [] = {
 253         [STRING_MANUFACTURER].s = manufacturer,
 254         [STRING_PRODUCT].s = product_desc,
 255         [STRING_SERIALNUM].s =  serial_num,
 256         {  }            /* end of list */
 257 };
 258
 259 static struct usb_gadget_strings        stringtab_dev = {
 260         .language       = 0x0409,       /* en-us */
 261         .strings        = strings,
 262 };
 263
 264 static struct usb_gadget_strings *dev_strings[] = {
 265         &stringtab_dev,
 266         NULL,
 267 };
 268
 269 /*-------------------------------------------------------------------------*/
 270
 271 static struct usb_request *
 272 printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
 273 {
 274         struct usb_request      *req;
 275
 276         req = usb_ep_alloc_request(ep, gfp_flags);
 277
 278         if (req != NULL) {
 279                 req->length = len;
 280                 req->buf = kmalloc(len, gfp_flags);
 281                 if (req->buf == NULL) {
 282                         usb_ep_free_request(ep, req);
 283                         return NULL;
 284                 }
 285         }
 286
 287         return req;
 288 }
 289
 290 static void
 291 printer_req_free(struct usb_ep *ep, struct usb_request *req)
 292 {
 293         if (ep != NULL && req != NULL) {
 294                 kfree(req->buf);
 295                 usb_ep_free_request(ep, req);
 296         }
 297 }
 298
 299 /*-------------------------------------------------------------------------*/
 300
 301 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
 302 {
 303         struct printer_dev      *dev = ep->driver_data;
 304         int                     status = req->status;
 305         unsigned long           flags;
 306
 307         spin_lock_irqsave(&dev->lock, flags);
 308
 309         list_del_init(&req->list);      /* Remode from Active List */
 310
 311         switch (status) {
 312
 313         /* normal completion */
 314         case 0:
 315                 if (req->actual > 0) {
 316                         list_add_tail(&req->list, &dev->rx_buffers);
 317                         DBG(dev, "G_Printer : rx length %d\n", req->actual);
 318                 } else {
 319                         list_add(&req->list, &dev->rx_reqs);
 320                 }
 321                 break;
 322
 323         /* software-driven interface shutdown */
 324         case -ECONNRESET:               /* unlink */
 325         case -ESHUTDOWN:                /* disconnect etc */
 326                 VDBG(dev, "rx shutdown, code %d\n", status);
 327                 list_add(&req->list, &dev->rx_reqs);
 328                 break;
 329
 330         /* for hardware automagic (such as pxa) */
 331         case -ECONNABORTED:             /* endpoint reset */
 332                 DBG(dev, "rx %s reset\n", ep->name);
 333                 list_add(&req->list, &dev->rx_reqs);
 334                 break;
 335
 336         /* data overrun */
 337         case -EOVERFLOW:
 338                 /* FALLTHROUGH */
 339
 340         default:
 341                 DBG(dev, "rx status %d\n", status);
 342                 list_add(&req->list, &dev->rx_reqs);
 343                 break;
 344         }
 345
 346         wake_up_interruptible(&dev->rx_wait);
 347         spin_unlock_irqrestore(&dev->lock, flags);
 348 }
 349
 350 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
 351 {
 352         struct printer_dev      *dev = ep->driver_data;
 353
 354         switch (req->status) {
 355         default:
 356                 VDBG(dev, "tx err %d\n", req->status);
 357                 /* FALLTHROUGH */
 358         case -ECONNRESET:               /* unlink */
 359         case -ESHUTDOWN:                /* disconnect etc */
 360                 break;
 361         case 0:
 362                 break;
 363         }
 364
 365         spin_lock(&dev->lock);
 366         /* Take the request struct off the active list and put it on the
 367          * free list.
 368          */
 369         list_del_init(&req->list);
 370         list_add(&req->list, &dev->tx_reqs);
 371         wake_up_interruptible(&dev->tx_wait);
 372         if (likely(list_empty(&dev->tx_reqs_active)))
 373                 wake_up_interruptible(&dev->tx_flush_wait);
 374
 375         spin_unlock(&dev->lock);
 376 }
 377
 378 /*-------------------------------------------------------------------------*/
 379
 380 static int
 381 printer_open(struct inode *inode, struct file *fd)
 382 {
 383         struct printer_dev      *dev;
 384         unsigned long           flags;
 385         int                     ret = -EBUSY;
 386
 387         mutex_lock(&printer_mutex);
 388         dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
 389
 390         spin_lock_irqsave(&dev->lock, flags);
 391
 392         if (!dev->printer_cdev_open) {
 393                 dev->printer_cdev_open = 1;
 394                 fd->private_data = dev;
 395                 ret = 0;
 396                 /* Change the printer status to show that it's on-line. */
 397                 dev->printer_status |= PRINTER_SELECTED;
 398         }
 399
 400         spin_unlock_irqrestore(&dev->lock, flags);
 401
 402         DBG(dev, "printer_open returned %x\n", ret);
 403         mutex_unlock(&printer_mutex);
 404         return ret;
 405 }
 406
 407 static int
 408 printer_close(struct inode *inode, struct file *fd)
 409 {
 410         struct printer_dev      *dev = fd->private_data;
 411         unsigned long           flags;
 412
 413         spin_lock_irqsave(&dev->lock, flags);
 414         dev->printer_cdev_open = 0;
 415         fd->private_data = NULL;
 416         /* Change printer status to show that the printer is off-line. */
 417         dev->printer_status &= ~PRINTER_SELECTED;
 418         spin_unlock_irqrestore(&dev->lock, flags);
 419
 420         DBG(dev, "printer_close\n");
 421
 422         return 0;
 423 }
 424
 425 /* This function must be called with interrupts turned off. */
 426 static void
 427 setup_rx_reqs(struct printer_dev *dev)
 428 {
 429         struct usb_request              *req;
 430
 431         while (likely(!list_empty(&dev->rx_reqs))) {
 432                 int error;
 433
 434                 req = container_of(dev->rx_reqs.next,
 435                                 struct usb_request, list);
 436                 list_del_init(&req->list);
 437
 438                 /* The USB Host sends us whatever amount of data it wants to
 439                  * so we always set the length field to the full USB_BUFSIZE.
 440                  * If the amount of data is more than the read() caller asked
 441                  * for it will be stored in the request buffer until it is
 442                  * asked for by read().
 443                  */
 444                 req->length = USB_BUFSIZE;
 445                 req->complete = rx_complete;
 446
 447                 error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
 448                 if (error) {
 449                         DBG(dev, "rx submit --> %d\n", error);
 450                         list_add(&req->list, &dev->rx_reqs);
 451                         break;
 452                 } else {
 453                         list_add(&req->list, &dev->rx_reqs_active);
 454                 }
 455         }
 456 }
 457
 458 static ssize_t
 459 printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
 460 {
 461         struct printer_dev              *dev = fd->private_data;
 462         unsigned long                   flags;
 463         size_t                          size;
 464         size_t                          bytes_copied;
 465         struct usb_request              *req;
 466         /* This is a pointer to the current USB rx request. */
 467         struct usb_request              *current_rx_req;
 468         /* This is the number of bytes in the current rx buffer. */
 469         size_t                          current_rx_bytes;
 470         /* This is a pointer to the current rx buffer. */
 471         u8                              *current_rx_buf;
 472
 473         if (len == 0)
 474                 return -EINVAL;
 475
 476         DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
 477
 478         mutex_lock(&dev->lock_printer_io);
 479         spin_lock_irqsave(&dev->lock, flags);
 480
 481         /* We will use this flag later to check if a printer reset happened
 482          * after we turn interrupts back on.
 483          */
 484         dev->reset_printer = 0;
 485
 486         setup_rx_reqs(dev);
 487
 488         bytes_copied = 0;
 489         current_rx_req = dev->current_rx_req;
 490         current_rx_bytes = dev->current_rx_bytes;
 491         current_rx_buf = dev->current_rx_buf;
 492         dev->current_rx_req = NULL;
 493         dev->current_rx_bytes = 0;
 494         dev->current_rx_buf = NULL;
 495
 496         /* Check if there is any data in the read buffers. Please note that
 497          * current_rx_bytes is the number of bytes in the current rx buffer.
 498          * If it is zero then check if there are any other rx_buffers that
 499          * are on the completed list. We are only out of data if all rx
 500          * buffers are empty.
 501          */
 502         if ((current_rx_bytes == 0) &&
 503                         (likely(list_empty(&dev->rx_buffers)))) {
 504                 /* Turn interrupts back on before sleeping. */
 505                 spin_unlock_irqrestore(&dev->lock, flags);
 506
 507                 /*
 508                  * If no data is available check if this is a NON-Blocking
 509                  * call or not.
 510                  */
 511                 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
 512                         mutex_unlock(&dev->lock_printer_io);
 513                         return -EAGAIN;
 514                 }
 515
 516                 /* Sleep until data is available */
 517                 wait_event_interruptible(dev->rx_wait,
 518                                 (likely(!list_empty(&dev->rx_buffers))));
 519                 spin_lock_irqsave(&dev->lock, flags);
 520         }
 521
 522         /* We have data to return then copy it to the caller's buffer.*/
 523         while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
 524                         && len) {
 525                 if (current_rx_bytes == 0) {
 526                         req = container_of(dev->rx_buffers.next,
 527                                         struct usb_request, list);
 528                         list_del_init(&req->list);
 529
 530                         if (req->actual && req->buf) {
 531                                 current_rx_req = req;
 532                                 current_rx_bytes = req->actual;
 533                                 current_rx_buf = req->buf;
 534                         } else {
 535                                 list_add(&req->list, &dev->rx_reqs);
 536                                 continue;
 537                         }
 538                 }
 539
 540                 /* Don't leave irqs off while doing memory copies */
 541                 spin_unlock_irqrestore(&dev->lock, flags);
 542
 543                 if (len > current_rx_bytes)
 544                         size = current_rx_bytes;
 545                 else
 546                         size = len;
 547
 548                 size -= copy_to_user(buf, current_rx_buf, size);
 549                 bytes_copied += size;
 550                 len -= size;
 551                 buf += size;
 552
 553                 spin_lock_irqsave(&dev->lock, flags);
 554
 555                 /* We've disconnected or reset so return. */
 556                 if (dev->reset_printer) {
 557                         list_add(&current_rx_req->list, &dev->rx_reqs);
 558                         spin_unlock_irqrestore(&dev->lock, flags);
 559                         mutex_unlock(&dev->lock_printer_io);
 560                         return -EAGAIN;
 561                 }
 562
 563                 /* If we not returning all the data left in this RX request
 564                  * buffer then adjust the amount of data left in the buffer.
 565                  * Othewise if we are done with this RX request buffer then
 566                  * requeue it to get any incoming data from the USB host.
 567                  */
 568                 if (size < current_rx_bytes) {
 569                         current_rx_bytes -= size;
 570                         current_rx_buf += size;
 571                 } else {
 572                         list_add(&current_rx_req->list, &dev->rx_reqs);
 573                         current_rx_bytes = 0;
 574                         current_rx_buf = NULL;
 575                         current_rx_req = NULL;
 576                 }
 577         }
 578
 579         dev->current_rx_req = current_rx_req;
 580         dev->current_rx_bytes = current_rx_bytes;
 581         dev->current_rx_buf = current_rx_buf;
 582
 583         spin_unlock_irqrestore(&dev->lock, flags);
 584         mutex_unlock(&dev->lock_printer_io);
 585
 586         DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
 587
 588         if (bytes_copied)
 589                 return bytes_copied;
 590         else
 591                 return -EAGAIN;
 592 }
 593
 594 static ssize_t
 595 printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 596 {
 597         struct printer_dev      *dev = fd->private_data;
 598         unsigned long           flags;
 599         size_t                  size;   /* Amount of data in a TX request. */
 600         size_t                  bytes_copied = 0;
 601         struct usb_request      *req;
 602
 603         DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
 604
 605         if (len == 0)
 606                 return -EINVAL;
 607
 608         mutex_lock(&dev->lock_printer_io);
 609         spin_lock_irqsave(&dev->lock, flags);
 610
 611         /* Check if a printer reset happens while we have interrupts on */
 612         dev->reset_printer = 0;
 613
 614         /* Check if there is any available write buffers */
 615         if (likely(list_empty(&dev->tx_reqs))) {
 616                 /* Turn interrupts back on before sleeping. */
 617                 spin_unlock_irqrestore(&dev->lock, flags);
 618
 619                 /*
 620                  * If write buffers are available check if this is
 621                  * a NON-Blocking call or not.
 622                  */
 623                 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
 624                         mutex_unlock(&dev->lock_printer_io);
 625                         return -EAGAIN;
 626                 }
 627
 628                 /* Sleep until a write buffer is available */
 629                 wait_event_interruptible(dev->tx_wait,
 630                                 (likely(!list_empty(&dev->tx_reqs))));
 631                 spin_lock_irqsave(&dev->lock, flags);
 632         }
 633
 634         while (likely(!list_empty(&dev->tx_reqs)) && len) {
 635
 636                 if (len > USB_BUFSIZE)
 637                         size = USB_BUFSIZE;
 638                 else
 639                         size = len;
 640
 641                 req = container_of(dev->tx_reqs.next, struct usb_request,
 642                                 list);
 643                 list_del_init(&req->list);
 644
 645                 req->complete = tx_complete;
 646                 req->length = size;
 647
 648                 /* Check if we need to send a zero length packet. */
 649                 if (len > size)
 650                         /* They will be more TX requests so no yet. */
 651                         req->zero = 0;
 652                 else
 653                         /* If the data amount is not a multple of the
 654                          * maxpacket size then send a zero length packet.
 655                          */
 656                         req->zero = ((len % dev->in_ep->maxpacket) == 0);
 657
 658                 /* Don't leave irqs off while doing memory copies */
 659                 spin_unlock_irqrestore(&dev->lock, flags);
 660
 661                 if (copy_from_user(req->buf, buf, size)) {
 662                         list_add(&req->list, &dev->tx_reqs);
 663                         mutex_unlock(&dev->lock_printer_io);
 664                         return bytes_copied;
 665                 }
 666
 667                 bytes_copied += size;
 668                 len -= size;
 669                 buf += size;
 670
 671                 spin_lock_irqsave(&dev->lock, flags);
 672
 673                 /* We've disconnected or reset so free the req and buffer */
 674                 if (dev->reset_printer) {
 675                         list_add(&req->list, &dev->tx_reqs);
 676                         spin_unlock_irqrestore(&dev->lock, flags);
 677                         mutex_unlock(&dev->lock_printer_io);
 678                         return -EAGAIN;
 679                 }
 680
 681                 if (usb_ep_queue(dev->in_ep, req, GFP_ATOMIC)) {
 682                         list_add(&req->list, &dev->tx_reqs);
 683                         spin_unlock_irqrestore(&dev->lock, flags);
 684                         mutex_unlock(&dev->lock_printer_io);
 685                         return -EAGAIN;
 686                 }
 687
 688                 list_add(&req->list, &dev->tx_reqs_active);
 689
 690         }
 691
 692         spin_unlock_irqrestore(&dev->lock, flags);
 693         mutex_unlock(&dev->lock_printer_io);
 694
 695         DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
 696
 697         if (bytes_copied) {
 698                 return bytes_copied;
 699         } else {
 700                 return -EAGAIN;
 701         }
 702 }
 703
 704 static int
 705 printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
 706 {
 707         struct printer_dev      *dev = fd->private_data;
 708         struct inode *inode = fd->f_path.dentry->d_inode;
 709         unsigned long           flags;
 710         int                     tx_list_empty;
 711
 712         mutex_lock(&inode->i_mutex);
 713         spin_lock_irqsave(&dev->lock, flags);
 714         tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
 715         spin_unlock_irqrestore(&dev->lock, flags);
 716
 717         if (!tx_list_empty) {
 718                 /* Sleep until all data has been sent */
 719                 wait_event_interruptible(dev->tx_flush_wait,
 720                                 (likely(list_empty(&dev->tx_reqs_active))));
 721         }
 722         mutex_unlock(&inode->i_mutex);
 723
 724         return 0;
 725 }
 726
 727 static unsigned int
 728 printer_poll(struct file *fd, poll_table *wait)
 729 {
 730         struct printer_dev      *dev = fd->private_data;
 731         unsigned long           flags;
 732         int                     status = 0;
 733
 734         mutex_lock(&dev->lock_printer_io);
 735         spin_lock_irqsave(&dev->lock, flags);
 736         setup_rx_reqs(dev);
 737         spin_unlock_irqrestore(&dev->lock, flags);
 738         mutex_unlock(&dev->lock_printer_io);
 739
 740         poll_wait(fd, &dev->rx_wait, wait);
 741         poll_wait(fd, &dev->tx_wait, wait);
 742
 743         spin_lock_irqsave(&dev->lock, flags);
 744         if (likely(!list_empty(&dev->tx_reqs)))
 745                 status |= POLLOUT | POLLWRNORM;
 746
 747         if (likely(dev->current_rx_bytes) ||
 748                         likely(!list_empty(&dev->rx_buffers)))
 749                 status |= POLLIN | POLLRDNORM;
 750
 751         spin_unlock_irqrestore(&dev->lock, flags);
 752
 753         return status;
 754 }
 755
 756 static long
 757 printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
 758 {
 759         struct printer_dev      *dev = fd->private_data;
 760         unsigned long           flags;
 761         int                     status = 0;
 762
 763         DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
 764
 765         /* handle ioctls */
 766
 767         spin_lock_irqsave(&dev->lock, flags);
 768
 769         switch (code) {
 770         case GADGET_GET_PRINTER_STATUS:
 771                 status = (int)dev->printer_status;
 772                 break;
 773         case GADGET_SET_PRINTER_STATUS:
 774                 dev->printer_status = (u8)arg;
 775                 break;
 776         default:
 777                 /* could not handle ioctl */
 778                 DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
 779                                 code);
 780                 status = -ENOTTY;
 781         }
 782
 783         spin_unlock_irqrestore(&dev->lock, flags);
 784
 785         return status;
 786 }
 787
 788 /* used after endpoint configuration */
 789 static const struct file_operations printer_io_operations = {
 790         .owner =        THIS_MODULE,
 791         .open =         printer_open,
 792         .read =         printer_read,
 793         .write =        printer_write,
 794         .fsync =        printer_fsync,
 795         .poll =         printer_poll,
 796         .unlocked_ioctl = printer_ioctl,
 797         .release =      printer_close,
 798         .llseek =       noop_llseek,
 799 };
 800
 801 /*-------------------------------------------------------------------------*/
 802
 803 static int
 804 set_printer_interface(struct printer_dev *dev)
 805 {
 806         int                     result = 0;
 807
 808         dev->in_ep->desc = ep_desc(dev->gadget, &hs_ep_in_desc, &fs_ep_in_desc);
 809         dev->in_ep->driver_data = dev;
 810
 811         dev->out_ep->desc = ep_desc(dev->gadget, &hs_ep_out_desc,
 812                                     &fs_ep_out_desc);
 813         dev->out_ep->driver_data = dev;
 814
 815         result = usb_ep_enable(dev->in_ep);
 816         if (result != 0) {
 817                 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
 818                 goto done;
 819         }
 820
 821         result = usb_ep_enable(dev->out_ep);
 822         if (result != 0) {
 823                 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
 824                 goto done;
 825         }
 826
 827 done:
 828         /* on error, disable any endpoints  */
 829         if (result != 0) {
 830                 (void) usb_ep_disable(dev->in_ep);
 831                 (void) usb_ep_disable(dev->out_ep);
 832                 dev->in_ep->desc = NULL;
 833                 dev->out_ep->desc = NULL;
 834         }
 835
 836         /* caller is responsible for cleanup on error */
 837         return result;
 838 }
 839
 840 static void printer_reset_interface(struct printer_dev *dev)
 841 {
 842         if (dev->interface < 0)
 843                 return;
 844
 845         DBG(dev, "%s\n", __func__);
 846
 847         if (dev->in_ep->desc)
 848                 usb_ep_disable(dev->in_ep);
 849
 850         if (dev->out_ep->desc)
 851                 usb_ep_disable(dev->out_ep);
 852
 853         dev->in_ep->desc = NULL;
 854         dev->out_ep->desc = NULL;
 855         dev->interface = -1;
 856 }
 857
 858 /* Change our operational Interface. */
 859 static int set_interface(struct printer_dev *dev, unsigned number)
 860 {
 861         int                     result = 0;
 862
 863         /* Free the current interface */
 864         printer_reset_interface(dev);
 865
 866         result = set_printer_interface(dev);
 867         if (result)
 868                 printer_reset_interface(dev);
 869         else
 870                 dev->interface = number;
 871
 872         if (!result)
 873                 INFO(dev, "Using interface %x\n", number);
 874
 875         return result;
 876 }
 877
 878 static void printer_soft_reset(struct printer_dev *dev)
 879 {
 880         struct usb_request      *req;
 881
 882         INFO(dev, "Received Printer Reset Request\n");
 883
 884         if (usb_ep_disable(dev->in_ep))
 885                 DBG(dev, "Failed to disable USB in_ep\n");
 886         if (usb_ep_disable(dev->out_ep))
 887                 DBG(dev, "Failed to disable USB out_ep\n");
 888
 889         if (dev->current_rx_req != NULL) {
 890                 list_add(&dev->current_rx_req->list, &dev->rx_reqs);
 891                 dev->current_rx_req = NULL;
 892         }
 893         dev->current_rx_bytes = 0;
 894         dev->current_rx_buf = NULL;
 895         dev->reset_printer = 1;
 896
 897         while (likely(!(list_empty(&dev->rx_buffers)))) {
 898                 req = container_of(dev->rx_buffers.next, struct usb_request,
 899                                 list);
 900                 list_del_init(&req->list);
 901                 list_add(&req->list, &dev->rx_reqs);
 902         }
 903
 904         while (likely(!(list_empty(&dev->rx_reqs_active)))) {
 905                 req = container_of(dev->rx_buffers.next, struct usb_request,
 906                                 list);
 907                 list_del_init(&req->list);
 908                 list_add(&req->list, &dev->rx_reqs);
 909         }
 910
 911         while (likely(!(list_empty(&dev->tx_reqs_active)))) {
 912                 req = container_of(dev->tx_reqs_active.next,
 913                                 struct usb_request, list);
 914                 list_del_init(&req->list);
 915                 list_add(&req->list, &dev->tx_reqs);
 916         }
 917
 918         if (usb_ep_enable(dev->in_ep))
 919                 DBG(dev, "Failed to enable USB in_ep\n");
 920         if (usb_ep_enable(dev->out_ep))
 921                 DBG(dev, "Failed to enable USB out_ep\n");
 922
 923         wake_up_interruptible(&dev->rx_wait);
 924         wake_up_interruptible(&dev->tx_wait);
 925         wake_up_interruptible(&dev->tx_flush_wait);
 926 }
 927
 928 /*-------------------------------------------------------------------------*/
 929
 930 /*
 931  * The setup() callback implements all the ep0 functionality that's not
 932  * handled lower down.
 933  */
 934 static int printer_func_setup(struct usb_function *f,
 935                 const struct usb_ctrlrequest *ctrl)
 936 {
 937         struct printer_dev *dev = container_of(f, struct printer_dev, function);
 938         struct usb_composite_dev *cdev = f->config->cdev;
 939         struct usb_request      *req = cdev->req;
 940         int                     value = -EOPNOTSUPP;
 941         u16                     wIndex = le16_to_cpu(ctrl->wIndex);
 942         u16                     wValue = le16_to_cpu(ctrl->wValue);
 943         u16                     wLength = le16_to_cpu(ctrl->wLength);
 944
 945         DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
 946                 ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
 947
 948         switch (ctrl->bRequestType&USB_TYPE_MASK) {
 949         case USB_TYPE_CLASS:
 950                 switch (ctrl->bRequest) {
 951                 case 0: /* Get the IEEE-1284 PNP String */
 952                         /* Only one printer interface is supported. */
 953                         if ((wIndex>>8) != dev->interface)
 954                                 break;
 955
 956                         value = (pnp_string[0]<<8)|pnp_string[1];
 957                         memcpy(req->buf, pnp_string, value);
 958                         DBG(dev, "1284 PNP String: %x %s\n", value,
 959                                         &pnp_string[2]);
 960                         break;
 961
 962                 case 1: /* Get Port Status */
 963                         /* Only one printer interface is supported. */
 964                         if (wIndex != dev->interface)
 965                                 break;
 966
 967                         *(u8 *)req->buf = dev->printer_status;
 968                         value = min(wLength, (u16) 1);
 969                         break;
 970
 971                 case 2: /* Soft Reset */
 972                         /* Only one printer interface is supported. */
 973                         if (wIndex != dev->interface)
 974                                 break;
 975
 976                         printer_soft_reset(dev);
 977
 978                         value = 0;
 979                         break;
 980
 981                 default:
 982                         goto unknown;
 983                 }
 984                 break;
 985
 986         default:
 987 unknown:
 988                 VDBG(dev,
 989                         "unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
 990                         ctrl->bRequestType, ctrl->bRequest,
 991                         wValue, wIndex, wLength);
 992                 break;
 993         }
 994         /* host either stalls (value < 0) or reports success */
 995         return value;
 996 }
 997
 998 static int __init printer_func_bind(struct usb_configuration *c,
 999                 struct usb_function *f)
1000 {
1001         struct printer_dev *dev = container_of(f, struct printer_dev, function);
1002         struct usb_composite_dev *cdev = c->cdev;
1003         struct usb_ep           *in_ep, *out_ep;
1004         int id;
1005
1006         id = usb_interface_id(c, f);
1007         if (id < 0)
1008                 return id;
1009         intf_desc.bInterfaceNumber = id;
1010
1011         /* all we really need is bulk IN/OUT */
1012         in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
1013         if (!in_ep) {
1014 autoconf_fail:
1015                 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
1016                         cdev->gadget->name);
1017                 return -ENODEV;
1018         }
1019         in_ep->driver_data = in_ep;     /* claim */
1020
1021         out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
1022         if (!out_ep)
1023                 goto autoconf_fail;
1024         out_ep->driver_data = out_ep;   /* claim */
1025
1026         /* assumes that all endpoints are dual-speed */
1027         hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1028         hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1029
1030         dev->in_ep = in_ep;
1031         dev->out_ep = out_ep;
1032         return 0;
1033 }
1034
1035 static void printer_func_unbind(struct usb_configuration *c,
1036                 struct usb_function *f)
1037 {
1038 }
1039
1040 static int printer_func_set_alt(struct usb_function *f,
1041                 unsigned intf, unsigned alt)
1042 {
1043         struct printer_dev *dev = container_of(f, struct printer_dev, function);
1044         int ret = -ENOTSUPP;
1045
1046         if (!alt)
1047                 ret = set_interface(dev, intf);
1048
1049         return ret;
1050 }
1051
1052 static void printer_func_disable(struct usb_function *f)
1053 {
1054         struct printer_dev *dev = container_of(f, struct printer_dev, function);
1055         unsigned long           flags;
1056
1057         DBG(dev, "%s\n", __func__);
1058
1059         spin_lock_irqsave(&dev->lock, flags);
1060         printer_reset_interface(dev);
1061         spin_unlock_irqrestore(&dev->lock, flags);
1062 }
1063
1064 static void printer_cfg_unbind(struct usb_configuration *c)
1065 {
1066         struct printer_dev      *dev;
1067         struct usb_request      *req;
1068
1069         dev = &usb_printer_gadget;
1070
1071         DBG(dev, "%s\n", __func__);
1072
1073         /* Remove sysfs files */
1074         device_destroy(usb_gadget_class, g_printer_devno);
1075
1076         /* Remove Character Device */
1077         cdev_del(&dev->printer_cdev);
1078
1079         /* we must already have been disconnected ... no i/o may be active */
1080         WARN_ON(!list_empty(&dev->tx_reqs_active));
1081         WARN_ON(!list_empty(&dev->rx_reqs_active));
1082
1083         /* Free all memory for this driver. */
1084         while (!list_empty(&dev->tx_reqs)) {
1085                 req = container_of(dev->tx_reqs.next, struct usb_request,
1086                                 list);
1087                 list_del(&req->list);
1088                 printer_req_free(dev->in_ep, req);
1089         }
1090
1091         if (dev->current_rx_req != NULL)
1092                 printer_req_free(dev->out_ep, dev->current_rx_req);
1093
1094         while (!list_empty(&dev->rx_reqs)) {
1095                 req = container_of(dev->rx_reqs.next,
1096                                 struct usb_request, list);
1097                 list_del(&req->list);
1098                 printer_req_free(dev->out_ep, req);
1099         }
1100
1101         while (!list_empty(&dev->rx_buffers)) {
1102                 req = container_of(dev->rx_buffers.next,
1103                                 struct usb_request, list);
1104                 list_del(&req->list);
1105                 printer_req_free(dev->out_ep, req);
1106         }
1107 }
1108
1109 static struct usb_configuration printer_cfg_driver = {
1110         .label                  = "printer",
1111         .unbind                 = printer_cfg_unbind,
1112         .bConfigurationValue    = 1,
1113         .bmAttributes           = USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
1114 };
1115
1116 static int __init printer_bind_config(struct usb_configuration *c)
1117 {
1118         struct usb_gadget       *gadget = c->cdev->gadget;
1119         struct printer_dev      *dev;
1120         int                     status = -ENOMEM;
1121         int                     gcnum;
1122         size_t                  len;
1123         u32                     i;
1124         struct usb_request      *req;
1125
1126         usb_ep_autoconfig_reset(gadget);
1127
1128         dev = &usb_printer_gadget;
1129
1130         dev->function.name = shortname;
1131         dev->function.descriptors = fs_printer_function;
1132         dev->function.hs_descriptors = hs_printer_function;
1133         dev->function.bind = printer_func_bind;
1134         dev->function.setup = printer_func_setup;
1135         dev->function.unbind = printer_func_unbind;
1136         dev->function.set_alt = printer_func_set_alt;
1137         dev->function.disable = printer_func_disable;
1138
1139         status = usb_add_function(c, &dev->function);
1140         if (status)
1141                 return status;
1142
1143         /* Setup the sysfs files for the printer gadget. */
1144         dev->pdev = device_create(usb_gadget_class, NULL, g_printer_devno,
1145                                   NULL, "g_printer");
1146         if (IS_ERR(dev->pdev)) {
1147                 ERROR(dev, "Failed to create device: g_printer\n");
1148                 goto fail;
1149         }
1150
1151         /*
1152          * Register a character device as an interface to a user mode
1153          * program that handles the printer specific functionality.
1154          */
1155         cdev_init(&dev->printer_cdev, &printer_io_operations);
1156         dev->printer_cdev.owner = THIS_MODULE;
1157         status = cdev_add(&dev->printer_cdev, g_printer_devno, 1);
1158         if (status) {
1159                 ERROR(dev, "Failed to open char device\n");
1160                 goto fail;
1161         }
1162
1163         gcnum = usb_gadget_controller_number(gadget);
1164         if (gcnum >= 0) {
1165                 device_desc.bcdDevice = cpu_to_le16(0x0200 + gcnum);
1166         } else {
1167                 dev_warn(&gadget->dev, "controller '%s' not recognized\n",
1168                         gadget->name);
1169                 /* unrecognized, but safe unless bulk is REALLY quirky */
1170                 device_desc.bcdDevice =
1171                         cpu_to_le16(0xFFFF);
1172         }
1173         snprintf(manufacturer, sizeof(manufacturer), "%s %s with %s",
1174                 init_utsname()->sysname, init_utsname()->release,
1175                 gadget->name);
1176
1177         if (iSerialNum)
1178                 strlcpy(serial_num, iSerialNum, sizeof serial_num);
1179
1180         if (iPNPstring)
1181                 strlcpy(&pnp_string[2], iPNPstring, (sizeof pnp_string)-2);
1182
1183         len = strlen(pnp_string);
1184         pnp_string[0] = (len >> 8) & 0xFF;
1185         pnp_string[1] = len & 0xFF;
1186
1187         usb_gadget_set_selfpowered(gadget);
1188
1189         if (gadget->is_otg) {
1190                 otg_descriptor.bmAttributes |= USB_OTG_HNP;
1191                 printer_cfg_driver.descriptors = otg_desc;
1192                 printer_cfg_driver.bmAttributes |= USB_CONFIG_ATT_WAKEUP;
1193         }
1194
1195         spin_lock_init(&dev->lock);
1196         mutex_init(&dev->lock_printer_io);
1197         INIT_LIST_HEAD(&dev->tx_reqs);
1198         INIT_LIST_HEAD(&dev->tx_reqs_active);
1199         INIT_LIST_HEAD(&dev->rx_reqs);
1200         INIT_LIST_HEAD(&dev->rx_reqs_active);
1201         INIT_LIST_HEAD(&dev->rx_buffers);
1202         init_waitqueue_head(&dev->rx_wait);
1203         init_waitqueue_head(&dev->tx_wait);
1204         init_waitqueue_head(&dev->tx_flush_wait);
1205
1206         dev->interface = -1;
1207         dev->printer_cdev_open = 0;
1208         dev->printer_status = PRINTER_NOT_ERROR;
1209         dev->current_rx_req = NULL;
1210         dev->current_rx_bytes = 0;
1211         dev->current_rx_buf = NULL;
1212
1213         for (i = 0; i < QLEN; i++) {
1214                 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
1215                 if (!req) {
1216                         while (!list_empty(&dev->tx_reqs)) {
1217                                 req = container_of(dev->tx_reqs.next,
1218                                                 struct usb_request, list);
1219                                 list_del(&req->list);
1220                                 printer_req_free(dev->in_ep, req);
1221                         }
1222                         return -ENOMEM;
1223                 }
1224                 list_add(&req->list, &dev->tx_reqs);
1225         }
1226
1227         for (i = 0; i < QLEN; i++) {
1228                 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
1229                 if (!req) {
1230                         while (!list_empty(&dev->rx_reqs)) {
1231                                 req = container_of(dev->rx_reqs.next,
1232                                                 struct usb_request, list);
1233                                 list_del(&req->list);
1234                                 printer_req_free(dev->out_ep, req);
1235                         }
1236                         return -ENOMEM;
1237                 }
1238                 list_add(&req->list, &dev->rx_reqs);
1239         }
1240
1241         /* finish hookup to lower layer ... */
1242         dev->gadget = gadget;
1243
1244         INFO(dev, "%s, version: " DRIVER_VERSION "\n", driver_desc);
1245         return 0;
1246
1247 fail:
1248         printer_cfg_unbind(c);
1249         return status;
1250 }
1251
1252 static int printer_unbind(struct usb_composite_dev *cdev)
1253 {
1254         return 0;
1255 }
1256
1257 static int __init printer_bind(struct usb_composite_dev *cdev)
1258 {
1259         int ret;
1260
1261         ret = usb_string_ids_tab(cdev, strings);
1262         if (ret < 0)
1263                 return ret;
1264         device_desc.iManufacturer = strings[STRING_MANUFACTURER].id;
1265         device_desc.iProduct = strings[STRING_PRODUCT].id;
1266         device_desc.iSerialNumber = strings[STRING_SERIALNUM].id;
1267
1268         ret = usb_add_config(cdev, &printer_cfg_driver, printer_bind_config);
1269         if (ret)
1270                 return ret;
1271         usb_composite_overwrite_options(cdev, &coverwrite);
1272         return ret;
1273 }
1274
1275 static __refdata struct usb_composite_driver printer_driver = {
1276         .name           = shortname,
1277         .dev            = &device_desc,
1278         .strings        = dev_strings,
1279         .max_speed      = USB_SPEED_HIGH,
1280         .bind           = printer_bind,
1281         .unbind         = printer_unbind,
1282 };
1283
1284 static int __init
1285 init(void)
1286 {
1287         int status;
1288
1289         usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
1290         if (IS_ERR(usb_gadget_class)) {
1291                 status = PTR_ERR(usb_gadget_class);
1292                 pr_err("unable to create usb_gadget class %d\n", status);
1293                 return status;
1294         }
1295
1296         status = alloc_chrdev_region(&g_printer_devno, 0, 1,
1297                         "USB printer gadget");
1298         if (status) {
1299                 pr_err("alloc_chrdev_region %d\n", status);
1300                 class_destroy(usb_gadget_class);
1301                 return status;
1302         }
1303
1304         status = usb_composite_probe(&printer_driver);
1305         if (status) {
1306                 class_destroy(usb_gadget_class);
1307                 unregister_chrdev_region(g_printer_devno, 1);
1308                 pr_err("usb_gadget_probe_driver %x\n", status);
1309         }
1310
1311         return status;
1312 }
1313 module_init(init);
1314
1315 static void __exit
1316 cleanup(void)
1317 {
1318         mutex_lock(&usb_printer_gadget.lock_printer_io);
1319         usb_composite_unregister(&printer_driver);
1320         unregister_chrdev_region(g_printer_devno, 1);
1321         class_destroy(usb_gadget_class);
1322         mutex_unlock(&usb_printer_gadget.lock_printer_io);
1323 }
1324 module_exit(cleanup);
1325
1326 MODULE_DESCRIPTION(DRIVER_DESC);
1327 MODULE_AUTHOR("Craig Nadler");
1328 MODULE_LICENSE("GPL");