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