kernel/drivers/usb/gadget/function/f_printer.c

   1 /*
   2  * f_printer.c - USB printer function driver
   3  *
   4  * Copied from drivers/usb/gadget/legacy/printer.c,
   5  * which was:
   6  *
   7  * printer.c -- Printer gadget driver
   8  *
   9  * Copyright (C) 2003-2005 David Brownell
  10  * Copyright (C) 2006 Craig W. Nadler
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/delay.h>
  21 #include <linux/ioport.h>
  22 #include <linux/sched.h>
  23 #include <linux/slab.h>
  24 #include <linux/mutex.h>
  25 #include <linux/errno.h>
  26 #include <linux/init.h>
  27 #include <linux/idr.h>
  28 #include <linux/timer.h>
  29 #include <linux/list.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/device.h>
  32 #include <linux/moduleparam.h>
  33 #include <linux/fs.h>
  34 #include <linux/poll.h>
  35 #include <linux/types.h>
  36 #include <linux/ctype.h>
  37 #include <linux/cdev.h>
  38
  39 #include <asm/byteorder.h>
  40 #include <linux/io.h>
  41 #include <linux/irq.h>
  42 #include <linux/uaccess.h>
  43 #include <asm/unaligned.h>
  44
  45 #include <linux/usb/ch9.h>
  46 #include <linux/usb/composite.h>
  47 #include <linux/usb/gadget.h>
  48 #include <linux/usb/g_printer.h>
  49
  50 #include "u_printer.h"
  51
  52 #define PNP_STRING_LEN          1024
  53 #define PRINTER_MINORS          4
  54 #define GET_DEVICE_ID           0
  55 #define GET_PORT_STATUS         1
  56 #define SOFT_RESET              2
  57
  58 static int major, minors;
  59 static struct class *usb_gadget_class;
  60 static DEFINE_IDA(printer_ida);
  61 static DEFINE_MUTEX(printer_ida_lock); /* protects access do printer_ida */
  62
  63 /*-------------------------------------------------------------------------*/
  64
  65 struct printer_dev {
  66         spinlock_t              lock;           /* lock this structure */
  67         /* lock buffer lists during read/write calls */
  68         struct mutex            lock_printer_io;
  69         struct usb_gadget       *gadget;
  70         s8                      interface;
  71         struct usb_ep           *in_ep, *out_ep;
  72
  73         struct list_head        rx_reqs;        /* List of free RX structs */
  74         struct list_head        rx_reqs_active; /* List of Active RX xfers */
  75         struct list_head        rx_buffers;     /* List of completed xfers */
  76         /* wait until there is data to be read. */
  77         wait_queue_head_t       rx_wait;
  78         struct list_head        tx_reqs;        /* List of free TX structs */
  79         struct list_head        tx_reqs_active; /* List of Active TX xfers */
  80         /* Wait until there are write buffers available to use. */
  81         wait_queue_head_t       tx_wait;
  82         /* Wait until all write buffers have been sent. */
  83         wait_queue_head_t       tx_flush_wait;
  84         struct usb_request      *current_rx_req;
  85         size_t                  current_rx_bytes;
  86         u8                      *current_rx_buf;
  87         u8                      printer_status;
  88         u8                      reset_printer;
  89         int                     minor;
  90         struct cdev             printer_cdev;
  91         u8                      printer_cdev_open;
  92         wait_queue_head_t       wait;
  93         unsigned                q_len;
  94         char                    *pnp_string;    /* We don't own memory! */
  95         struct usb_function     function;
  96 };
  97
  98 static inline struct printer_dev *func_to_printer(struct usb_function *f)
  99 {
 100         return container_of(f, struct printer_dev, function);
 101 }
 102
 103 /*-------------------------------------------------------------------------*/
 104
 105 /*
 106  * DESCRIPTORS ... most are static, but strings and (full) configuration
 107  * descriptors are built on demand.
 108  */
 109
 110 /* holds our biggest descriptor */
 111 #define USB_DESC_BUFSIZE                256
 112 #define USB_BUFSIZE                     8192
 113
 114 static struct usb_interface_descriptor intf_desc = {
 115         .bLength =              sizeof(intf_desc),
 116         .bDescriptorType =      USB_DT_INTERFACE,
 117         .bNumEndpoints =        2,
 118         .bInterfaceClass =      USB_CLASS_PRINTER,
 119         .bInterfaceSubClass =   1,      /* Printer Sub-Class */
 120         .bInterfaceProtocol =   2,      /* Bi-Directional */
 121         .iInterface =           0
 122 };
 123
 124 static struct usb_endpoint_descriptor fs_ep_in_desc = {
 125         .bLength =              USB_DT_ENDPOINT_SIZE,
 126         .bDescriptorType =      USB_DT_ENDPOINT,
 127         .bEndpointAddress =     USB_DIR_IN,
 128         .bmAttributes =         USB_ENDPOINT_XFER_BULK
 129 };
 130
 131 static struct usb_endpoint_descriptor fs_ep_out_desc = {
 132         .bLength =              USB_DT_ENDPOINT_SIZE,
 133         .bDescriptorType =      USB_DT_ENDPOINT,
 134         .bEndpointAddress =     USB_DIR_OUT,
 135         .bmAttributes =         USB_ENDPOINT_XFER_BULK
 136 };
 137
 138 static struct usb_descriptor_header *fs_printer_function[] = {
 139         (struct usb_descriptor_header *) &intf_desc,
 140         (struct usb_descriptor_header *) &fs_ep_in_desc,
 141         (struct usb_descriptor_header *) &fs_ep_out_desc,
 142         NULL
 143 };
 144
 145 /*
 146  * usb 2.0 devices need to expose both high speed and full speed
 147  * descriptors, unless they only run at full speed.
 148  */
 149
 150 static struct usb_endpoint_descriptor hs_ep_in_desc = {
 151         .bLength =              USB_DT_ENDPOINT_SIZE,
 152         .bDescriptorType =      USB_DT_ENDPOINT,
 153         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 154         .wMaxPacketSize =       cpu_to_le16(512)
 155 };
 156
 157 static struct usb_endpoint_descriptor hs_ep_out_desc = {
 158         .bLength =              USB_DT_ENDPOINT_SIZE,
 159         .bDescriptorType =      USB_DT_ENDPOINT,
 160         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 161         .wMaxPacketSize =       cpu_to_le16(512)
 162 };
 163
 164 static struct usb_qualifier_descriptor dev_qualifier = {
 165         .bLength =              sizeof(dev_qualifier),
 166         .bDescriptorType =      USB_DT_DEVICE_QUALIFIER,
 167         .bcdUSB =               cpu_to_le16(0x0200),
 168         .bDeviceClass =         USB_CLASS_PRINTER,
 169         .bNumConfigurations =   1
 170 };
 171
 172 static struct usb_descriptor_header *hs_printer_function[] = {
 173         (struct usb_descriptor_header *) &intf_desc,
 174         (struct usb_descriptor_header *) &hs_ep_in_desc,
 175         (struct usb_descriptor_header *) &hs_ep_out_desc,
 176         NULL
 177 };
 178
 179 /*
 180  * Added endpoint descriptors for 3.0 devices
 181  */
 182
 183 static struct usb_endpoint_descriptor ss_ep_in_desc = {
 184         .bLength =              USB_DT_ENDPOINT_SIZE,
 185         .bDescriptorType =      USB_DT_ENDPOINT,
 186         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 187         .wMaxPacketSize =       cpu_to_le16(1024),
 188 };
 189
 190 static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = {
 191         .bLength =              sizeof(ss_ep_in_comp_desc),
 192         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 193 };
 194
 195 static struct usb_endpoint_descriptor ss_ep_out_desc = {
 196         .bLength =              USB_DT_ENDPOINT_SIZE,
 197         .bDescriptorType =      USB_DT_ENDPOINT,
 198         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 199         .wMaxPacketSize =       cpu_to_le16(1024),
 200 };
 201
 202 static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = {
 203         .bLength =              sizeof(ss_ep_out_comp_desc),
 204         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 205 };
 206
 207 static struct usb_descriptor_header *ss_printer_function[] = {
 208         (struct usb_descriptor_header *) &intf_desc,
 209         (struct usb_descriptor_header *) &ss_ep_in_desc,
 210         (struct usb_descriptor_header *) &ss_ep_in_comp_desc,
 211         (struct usb_descriptor_header *) &ss_ep_out_desc,
 212         (struct usb_descriptor_header *) &ss_ep_out_comp_desc,
 213         NULL
 214 };
 215
 216 /* maxpacket and other transfer characteristics vary by speed. */
 217 static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
 218                                         struct usb_endpoint_descriptor *fs,
 219                                         struct usb_endpoint_descriptor *hs,
 220                                         struct usb_endpoint_descriptor *ss)
 221 {
 222         switch (gadget->speed) {
 223         case USB_SPEED_SUPER:
 224                 return ss;
 225         case USB_SPEED_HIGH:
 226                 return hs;
 227         default:
 228                 return fs;
 229         }
 230 }
 231
 232 /*-------------------------------------------------------------------------*/
 233
 234 static struct usb_request *
 235 printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
 236 {
 237         struct usb_request      *req;
 238
 239         req = usb_ep_alloc_request(ep, gfp_flags);
 240
 241         if (req != NULL) {
 242                 req->length = len;
 243                 req->buf = kmalloc(len, gfp_flags);
 244                 if (req->buf == NULL) {
 245                         usb_ep_free_request(ep, req);
 246                         return NULL;
 247                 }
 248         }
 249
 250         return req;
 251 }
 252
 253 static void
 254 printer_req_free(struct usb_ep *ep, struct usb_request *req)
 255 {
 256         if (ep != NULL && req != NULL) {
 257                 kfree(req->buf);
 258                 usb_ep_free_request(ep, req);
 259         }
 260 }
 261
 262 /*-------------------------------------------------------------------------*/
 263
 264 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
 265 {
 266         struct printer_dev      *dev = ep->driver_data;
 267         int                     status = req->status;
 268         unsigned long           flags;
 269
 270         spin_lock_irqsave(&dev->lock, flags);
 271
 272         list_del_init(&req->list);      /* Remode from Active List */
 273
 274         switch (status) {
 275
 276         /* normal completion */
 277         case 0:
 278                 if (req->actual > 0) {
 279                         list_add_tail(&req->list, &dev->rx_buffers);
 280                         DBG(dev, "G_Printer : rx length %d\n", req->actual);
 281                 } else {
 282                         list_add(&req->list, &dev->rx_reqs);
 283                 }
 284                 break;
 285
 286         /* software-driven interface shutdown */
 287         case -ECONNRESET:               /* unlink */
 288         case -ESHUTDOWN:                /* disconnect etc */
 289                 VDBG(dev, "rx shutdown, code %d\n", status);
 290                 list_add(&req->list, &dev->rx_reqs);
 291                 break;
 292
 293         /* for hardware automagic (such as pxa) */
 294         case -ECONNABORTED:             /* endpoint reset */
 295                 DBG(dev, "rx %s reset\n", ep->name);
 296                 list_add(&req->list, &dev->rx_reqs);
 297                 break;
 298
 299         /* data overrun */
 300         case -EOVERFLOW:
 301                 /* FALLTHROUGH */
 302
 303         default:
 304                 DBG(dev, "rx status %d\n", status);
 305                 list_add(&req->list, &dev->rx_reqs);
 306                 break;
 307         }
 308
 309         wake_up_interruptible(&dev->rx_wait);
 310         spin_unlock_irqrestore(&dev->lock, flags);
 311 }
 312
 313 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
 314 {
 315         struct printer_dev      *dev = ep->driver_data;
 316
 317         switch (req->status) {
 318         default:
 319                 VDBG(dev, "tx err %d\n", req->status);
 320                 /* FALLTHROUGH */
 321         case -ECONNRESET:               /* unlink */
 322         case -ESHUTDOWN:                /* disconnect etc */
 323                 break;
 324         case 0:
 325                 break;
 326         }
 327
 328         spin_lock(&dev->lock);
 329         /* Take the request struct off the active list and put it on the
 330          * free list.
 331          */
 332         list_del_init(&req->list);
 333         list_add(&req->list, &dev->tx_reqs);
 334         wake_up_interruptible(&dev->tx_wait);
 335         if (likely(list_empty(&dev->tx_reqs_active)))
 336                 wake_up_interruptible(&dev->tx_flush_wait);
 337
 338         spin_unlock(&dev->lock);
 339 }
 340
 341 /*-------------------------------------------------------------------------*/
 342
 343 static int
 344 printer_open(struct inode *inode, struct file *fd)
 345 {
 346         struct printer_dev      *dev;
 347         unsigned long           flags;
 348         int                     ret = -EBUSY;
 349
 350         dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
 351
 352         spin_lock_irqsave(&dev->lock, flags);
 353
 354         if (!dev->printer_cdev_open) {
 355                 dev->printer_cdev_open = 1;
 356                 fd->private_data = dev;
 357                 ret = 0;
 358                 /* Change the printer status to show that it's on-line. */
 359                 dev->printer_status |= PRINTER_SELECTED;
 360         }
 361
 362         spin_unlock_irqrestore(&dev->lock, flags);
 363
 364         DBG(dev, "printer_open returned %x\n", ret);
 365         return ret;
 366 }
 367
 368 static int
 369 printer_close(struct inode *inode, struct file *fd)
 370 {
 371         struct printer_dev      *dev = fd->private_data;
 372         unsigned long           flags;
 373
 374         spin_lock_irqsave(&dev->lock, flags);
 375         dev->printer_cdev_open = 0;
 376         fd->private_data = NULL;
 377         /* Change printer status to show that the printer is off-line. */
 378         dev->printer_status &= ~PRINTER_SELECTED;
 379         spin_unlock_irqrestore(&dev->lock, flags);
 380
 381         DBG(dev, "printer_close\n");
 382
 383         return 0;
 384 }
 385
 386 /* This function must be called with interrupts turned off. */
 387 static void
 388 setup_rx_reqs(struct printer_dev *dev)
 389 {
 390         struct usb_request              *req;
 391
 392         while (likely(!list_empty(&dev->rx_reqs))) {
 393                 int error;
 394
 395                 req = container_of(dev->rx_reqs.next,
 396                                 struct usb_request, list);
 397                 list_del_init(&req->list);
 398
 399                 /* The USB Host sends us whatever amount of data it wants to
 400                  * so we always set the length field to the full USB_BUFSIZE.
 401                  * If the amount of data is more than the read() caller asked
 402                  * for it will be stored in the request buffer until it is
 403                  * asked for by read().
 404                  */
 405                 req->length = USB_BUFSIZE;
 406                 req->complete = rx_complete;
 407
 408                 /* here, we unlock, and only unlock, to avoid deadlock. */
 409                 spin_unlock(&dev->lock);
 410                 error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
 411                 spin_lock(&dev->lock);
 412                 if (error) {
 413                         DBG(dev, "rx submit --> %d\n", error);
 414                         list_add(&req->list, &dev->rx_reqs);
 415                         break;
 416                 }
 417                 /* if the req is empty, then add it into dev->rx_reqs_active. */
 418                 else if (list_empty(&req->list))
 419                         list_add(&req->list, &dev->rx_reqs_active);
 420         }
 421 }
 422
 423 static ssize_t
 424 printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
 425 {
 426         struct printer_dev              *dev = fd->private_data;
 427         unsigned long                   flags;
 428         size_t                          size;
 429         size_t                          bytes_copied;
 430         struct usb_request              *req;
 431         /* This is a pointer to the current USB rx request. */
 432         struct usb_request              *current_rx_req;
 433         /* This is the number of bytes in the current rx buffer. */
 434         size_t                          current_rx_bytes;
 435         /* This is a pointer to the current rx buffer. */
 436         u8                              *current_rx_buf;
 437
 438         if (len == 0)
 439                 return -EINVAL;
 440
 441         DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
 442
 443         mutex_lock(&dev->lock_printer_io);
 444         spin_lock_irqsave(&dev->lock, flags);
 445
 446         /* We will use this flag later to check if a printer reset happened
 447          * after we turn interrupts back on.
 448          */
 449         dev->reset_printer = 0;
 450
 451         setup_rx_reqs(dev);
 452
 453         bytes_copied = 0;
 454         current_rx_req = dev->current_rx_req;
 455         current_rx_bytes = dev->current_rx_bytes;
 456         current_rx_buf = dev->current_rx_buf;
 457         dev->current_rx_req = NULL;
 458         dev->current_rx_bytes = 0;
 459         dev->current_rx_buf = NULL;
 460
 461         /* Check if there is any data in the read buffers. Please note that
 462          * current_rx_bytes is the number of bytes in the current rx buffer.
 463          * If it is zero then check if there are any other rx_buffers that
 464          * are on the completed list. We are only out of data if all rx
 465          * buffers are empty.
 466          */
 467         if ((current_rx_bytes == 0) &&
 468                         (likely(list_empty(&dev->rx_buffers)))) {
 469                 /* Turn interrupts back on before sleeping. */
 470                 spin_unlock_irqrestore(&dev->lock, flags);
 471
 472                 /*
 473                  * If no data is available check if this is a NON-Blocking
 474                  * call or not.
 475                  */
 476                 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
 477                         mutex_unlock(&dev->lock_printer_io);
 478                         return -EAGAIN;
 479                 }
 480
 481                 /* Sleep until data is available */
 482                 wait_event_interruptible(dev->rx_wait,
 483                                 (likely(!list_empty(&dev->rx_buffers))));
 484                 spin_lock_irqsave(&dev->lock, flags);
 485         }
 486
 487         /* We have data to return then copy it to the caller's buffer.*/
 488         while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
 489                         && len) {
 490                 if (current_rx_bytes == 0) {
 491                         req = container_of(dev->rx_buffers.next,
 492                                         struct usb_request, list);
 493                         list_del_init(&req->list);
 494
 495                         if (req->actual && req->buf) {
 496                                 current_rx_req = req;
 497                                 current_rx_bytes = req->actual;
 498                                 current_rx_buf = req->buf;
 499                         } else {
 500                                 list_add(&req->list, &dev->rx_reqs);
 501                                 continue;
 502                         }
 503                 }
 504
 505                 /* Don't leave irqs off while doing memory copies */
 506                 spin_unlock_irqrestore(&dev->lock, flags);
 507
 508                 if (len > current_rx_bytes)
 509                         size = current_rx_bytes;
 510                 else
 511                         size = len;
 512
 513                 size -= copy_to_user(buf, current_rx_buf, size);
 514                 bytes_copied += size;
 515                 len -= size;
 516                 buf += size;
 517
 518                 spin_lock_irqsave(&dev->lock, flags);
 519
 520                 /* We've disconnected or reset so return. */
 521                 if (dev->reset_printer) {
 522                         list_add(&current_rx_req->list, &dev->rx_reqs);
 523                         spin_unlock_irqrestore(&dev->lock, flags);
 524                         mutex_unlock(&dev->lock_printer_io);
 525                         return -EAGAIN;
 526                 }
 527
 528                 /* If we not returning all the data left in this RX request
 529                  * buffer then adjust the amount of data left in the buffer.
 530                  * Othewise if we are done with this RX request buffer then
 531                  * requeue it to get any incoming data from the USB host.
 532                  */
 533                 if (size < current_rx_bytes) {
 534                         current_rx_bytes -= size;
 535                         current_rx_buf += size;
 536                 } else {
 537                         list_add(&current_rx_req->list, &dev->rx_reqs);
 538                         current_rx_bytes = 0;
 539                         current_rx_buf = NULL;
 540                         current_rx_req = NULL;
 541                 }
 542         }
 543
 544         dev->current_rx_req = current_rx_req;
 545         dev->current_rx_bytes = current_rx_bytes;
 546         dev->current_rx_buf = current_rx_buf;
 547
 548         spin_unlock_irqrestore(&dev->lock, flags);
 549         mutex_unlock(&dev->lock_printer_io);
 550
 551         DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
 552
 553         if (bytes_copied)
 554                 return bytes_copied;
 555         else
 556                 return -EAGAIN;
 557 }
 558
 559 static ssize_t
 560 printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 561 {
 562         struct printer_dev      *dev = fd->private_data;
 563         unsigned long           flags;
 564         size_t                  size;   /* Amount of data in a TX request. */
 565         size_t                  bytes_copied = 0;
 566         struct usb_request      *req;
 567
 568         DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
 569
 570         if (len == 0)
 571                 return -EINVAL;
 572
 573         mutex_lock(&dev->lock_printer_io);
 574         spin_lock_irqsave(&dev->lock, flags);
 575
 576         /* Check if a printer reset happens while we have interrupts on */
 577         dev->reset_printer = 0;
 578
 579         /* Check if there is any available write buffers */
 580         if (likely(list_empty(&dev->tx_reqs))) {
 581                 /* Turn interrupts back on before sleeping. */
 582                 spin_unlock_irqrestore(&dev->lock, flags);
 583
 584                 /*
 585                  * If write buffers are available check if this is
 586                  * a NON-Blocking call or not.
 587                  */
 588                 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
 589                         mutex_unlock(&dev->lock_printer_io);
 590                         return -EAGAIN;
 591                 }
 592
 593                 /* Sleep until a write buffer is available */
 594                 wait_event_interruptible(dev->tx_wait,
 595                                 (likely(!list_empty(&dev->tx_reqs))));
 596                 spin_lock_irqsave(&dev->lock, flags);
 597         }
 598
 599         while (likely(!list_empty(&dev->tx_reqs)) && len) {
 600
 601                 if (len > USB_BUFSIZE)
 602                         size = USB_BUFSIZE;
 603                 else
 604                         size = len;
 605
 606                 req = container_of(dev->tx_reqs.next, struct usb_request,
 607                                 list);
 608                 list_del_init(&req->list);
 609
 610                 req->complete = tx_complete;
 611                 req->length = size;
 612
 613                 /* Check if we need to send a zero length packet. */
 614                 if (len > size)
 615                         /* They will be more TX requests so no yet. */
 616                         req->zero = 0;
 617                 else
 618                         /* If the data amount is not a multiple of the
 619                          * maxpacket size then send a zero length packet.
 620                          */
 621                         req->zero = ((len % dev->in_ep->maxpacket) == 0);
 622
 623                 /* Don't leave irqs off while doing memory copies */
 624                 spin_unlock_irqrestore(&dev->lock, flags);
 625
 626                 if (copy_from_user(req->buf, buf, size)) {
 627                         list_add(&req->list, &dev->tx_reqs);
 628                         mutex_unlock(&dev->lock_printer_io);
 629                         return bytes_copied;
 630                 }
 631
 632                 bytes_copied += size;
 633                 len -= size;
 634                 buf += size;
 635
 636                 spin_lock_irqsave(&dev->lock, flags);
 637
 638                 /* We've disconnected or reset so free the req and buffer */
 639                 if (dev->reset_printer) {
 640                         list_add(&req->list, &dev->tx_reqs);
 641                         spin_unlock_irqrestore(&dev->lock, flags);
 642                         mutex_unlock(&dev->lock_printer_io);
 643                         return -EAGAIN;
 644                 }
 645
 646                 if (usb_ep_queue(dev->in_ep, req, GFP_ATOMIC)) {
 647                         list_add(&req->list, &dev->tx_reqs);
 648                         spin_unlock_irqrestore(&dev->lock, flags);
 649                         mutex_unlock(&dev->lock_printer_io);
 650                         return -EAGAIN;
 651                 }
 652
 653                 list_add(&req->list, &dev->tx_reqs_active);
 654
 655         }
 656
 657         spin_unlock_irqrestore(&dev->lock, flags);
 658         mutex_unlock(&dev->lock_printer_io);
 659
 660         DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
 661
 662         if (bytes_copied)
 663                 return bytes_copied;
 664         else
 665                 return -EAGAIN;
 666 }
 667
 668 static int
 669 printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
 670 {
 671         struct printer_dev      *dev = fd->private_data;
 672         struct inode *inode = file_inode(fd);
 673         unsigned long           flags;
 674         int                     tx_list_empty;
 675
 676         mutex_lock(&inode->i_mutex);
 677         spin_lock_irqsave(&dev->lock, flags);
 678         tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
 679         spin_unlock_irqrestore(&dev->lock, flags);
 680
 681         if (!tx_list_empty) {
 682                 /* Sleep until all data has been sent */
 683                 wait_event_interruptible(dev->tx_flush_wait,
 684                                 (likely(list_empty(&dev->tx_reqs_active))));
 685         }
 686         mutex_unlock(&inode->i_mutex);
 687
 688         return 0;
 689 }
 690
 691 static unsigned int
 692 printer_poll(struct file *fd, poll_table *wait)
 693 {
 694         struct printer_dev      *dev = fd->private_data;
 695         unsigned long           flags;
 696         int                     status = 0;
 697
 698         mutex_lock(&dev->lock_printer_io);
 699         spin_lock_irqsave(&dev->lock, flags);
 700         setup_rx_reqs(dev);
 701         spin_unlock_irqrestore(&dev->lock, flags);
 702         mutex_unlock(&dev->lock_printer_io);
 703
 704         poll_wait(fd, &dev->rx_wait, wait);
 705         poll_wait(fd, &dev->tx_wait, wait);
 706
 707         spin_lock_irqsave(&dev->lock, flags);
 708         if (likely(!list_empty(&dev->tx_reqs)))
 709                 status |= POLLOUT | POLLWRNORM;
 710
 711         if (likely(dev->current_rx_bytes) ||
 712                         likely(!list_empty(&dev->rx_buffers)))
 713                 status |= POLLIN | POLLRDNORM;
 714
 715         spin_unlock_irqrestore(&dev->lock, flags);
 716
 717         return status;
 718 }
 719
 720 static long
 721 printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
 722 {
 723         struct printer_dev      *dev = fd->private_data;
 724         unsigned long           flags;
 725         int                     status = 0;
 726
 727         DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
 728
 729         /* handle ioctls */
 730
 731         spin_lock_irqsave(&dev->lock, flags);
 732
 733         switch (code) {
 734         case GADGET_GET_PRINTER_STATUS:
 735                 status = (int)dev->printer_status;
 736                 break;
 737         case GADGET_SET_PRINTER_STATUS:
 738                 dev->printer_status = (u8)arg;
 739                 break;
 740         default:
 741                 /* could not handle ioctl */
 742                 DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
 743                                 code);
 744                 status = -ENOTTY;
 745         }
 746
 747         spin_unlock_irqrestore(&dev->lock, flags);
 748
 749         return status;
 750 }
 751
 752 /* used after endpoint configuration */
 753 static const struct file_operations printer_io_operations = {
 754         .owner =        THIS_MODULE,
 755         .open =         printer_open,
 756         .read =         printer_read,
 757         .write =        printer_write,
 758         .fsync =        printer_fsync,
 759         .poll =         printer_poll,
 760         .unlocked_ioctl = printer_ioctl,
 761         .release =      printer_close,
 762         .llseek =       noop_llseek,
 763 };
 764
 765 /*-------------------------------------------------------------------------*/
 766
 767 static int
 768 set_printer_interface(struct printer_dev *dev)
 769 {
 770         int                     result = 0;
 771
 772         dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
 773                                 &ss_ep_in_desc);
 774         dev->in_ep->driver_data = dev;
 775
 776         dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
 777                                     &hs_ep_out_desc, &ss_ep_out_desc);
 778         dev->out_ep->driver_data = dev;
 779
 780         result = usb_ep_enable(dev->in_ep);
 781         if (result != 0) {
 782                 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
 783                 goto done;
 784         }
 785
 786         result = usb_ep_enable(dev->out_ep);
 787         if (result != 0) {
 788                 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
 789                 goto done;
 790         }
 791
 792 done:
 793         /* on error, disable any endpoints  */
 794         if (result != 0) {
 795                 (void) usb_ep_disable(dev->in_ep);
 796                 (void) usb_ep_disable(dev->out_ep);
 797                 dev->in_ep->desc = NULL;
 798                 dev->out_ep->desc = NULL;
 799         }
 800
 801         /* caller is responsible for cleanup on error */
 802         return result;
 803 }
 804
 805 static void printer_reset_interface(struct printer_dev *dev)
 806 {
 807         if (dev->interface < 0)
 808                 return;
 809
 810         DBG(dev, "%s\n", __func__);
 811
 812         if (dev->in_ep->desc)
 813                 usb_ep_disable(dev->in_ep);
 814
 815         if (dev->out_ep->desc)
 816                 usb_ep_disable(dev->out_ep);
 817
 818         dev->in_ep->desc = NULL;
 819         dev->out_ep->desc = NULL;
 820         dev->interface = -1;
 821 }
 822
 823 /* Change our operational Interface. */
 824 static int set_interface(struct printer_dev *dev, unsigned number)
 825 {
 826         int                     result = 0;
 827
 828         /* Free the current interface */
 829         printer_reset_interface(dev);
 830
 831         result = set_printer_interface(dev);
 832         if (result)
 833                 printer_reset_interface(dev);
 834         else
 835                 dev->interface = number;
 836
 837         if (!result)
 838                 INFO(dev, "Using interface %x\n", number);
 839
 840         return result;
 841 }
 842
 843 static void printer_soft_reset(struct printer_dev *dev)
 844 {
 845         struct usb_request      *req;
 846
 847         INFO(dev, "Received Printer Reset Request\n");
 848
 849         if (usb_ep_disable(dev->in_ep))
 850                 DBG(dev, "Failed to disable USB in_ep\n");
 851         if (usb_ep_disable(dev->out_ep))
 852                 DBG(dev, "Failed to disable USB out_ep\n");
 853
 854         if (dev->current_rx_req != NULL) {
 855                 list_add(&dev->current_rx_req->list, &dev->rx_reqs);
 856                 dev->current_rx_req = NULL;
 857         }
 858         dev->current_rx_bytes = 0;
 859         dev->current_rx_buf = NULL;
 860         dev->reset_printer = 1;
 861
 862         while (likely(!(list_empty(&dev->rx_buffers)))) {
 863                 req = container_of(dev->rx_buffers.next, struct usb_request,
 864                                 list);
 865                 list_del_init(&req->list);
 866                 list_add(&req->list, &dev->rx_reqs);
 867         }
 868
 869         while (likely(!(list_empty(&dev->rx_reqs_active)))) {
 870                 req = container_of(dev->rx_buffers.next, struct usb_request,
 871                                 list);
 872                 list_del_init(&req->list);
 873                 list_add(&req->list, &dev->rx_reqs);
 874         }
 875
 876         while (likely(!(list_empty(&dev->tx_reqs_active)))) {
 877                 req = container_of(dev->tx_reqs_active.next,
 878                                 struct usb_request, list);
 879                 list_del_init(&req->list);
 880                 list_add(&req->list, &dev->tx_reqs);
 881         }
 882
 883         if (usb_ep_enable(dev->in_ep))
 884                 DBG(dev, "Failed to enable USB in_ep\n");
 885         if (usb_ep_enable(dev->out_ep))
 886                 DBG(dev, "Failed to enable USB out_ep\n");
 887
 888         wake_up_interruptible(&dev->rx_wait);
 889         wake_up_interruptible(&dev->tx_wait);
 890         wake_up_interruptible(&dev->tx_flush_wait);
 891 }
 892
 893 /*-------------------------------------------------------------------------*/
 894
 895 static bool gprinter_req_match(struct usb_function *f,
 896                                const struct usb_ctrlrequest *ctrl)
 897 {
 898         struct printer_dev      *dev = func_to_printer(f);
 899         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 900         u16                     w_value = le16_to_cpu(ctrl->wValue);
 901         u16                     w_length = le16_to_cpu(ctrl->wLength);
 902
 903         if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE ||
 904             (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
 905                 return false;
 906
 907         switch (ctrl->bRequest) {
 908         case GET_DEVICE_ID:
 909                 w_index >>= 8;
 910                 if (w_length <= PNP_STRING_LEN &&
 911                     (USB_DIR_IN & ctrl->bRequestType))
 912                         break;
 913                 return false;
 914         case GET_PORT_STATUS:
 915                 if (!w_value && w_length == 1 &&
 916                     (USB_DIR_IN & ctrl->bRequestType))
 917                         break;
 918                 return false;
 919         case SOFT_RESET:
 920                 if (!w_value && !w_length &&
 921                    !(USB_DIR_IN & ctrl->bRequestType))
 922                         break;
 923                 /* fall through */
 924         default:
 925                 return false;
 926         }
 927         return w_index == dev->interface;
 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 = func_to_printer(f);
 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 GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */
 952                         /* Only one printer interface is supported. */
 953                         if ((wIndex>>8) != dev->interface)
 954                                 break;
 955
 956                         value = (dev->pnp_string[0] << 8) | dev->pnp_string[1];
 957                         memcpy(req->buf, dev->pnp_string, value);
 958                         DBG(dev, "1284 PNP String: %x %s\n", value,
 959                                         &dev->pnp_string[2]);
 960                         break;
 961
 962                 case GET_PORT_STATUS: /* 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_t(u16, wLength, 1);
 969                         break;
 970
 971                 case SOFT_RESET: /* 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         if (value >= 0) {
 996                 req->length = value;
 997                 req->zero = value < wLength;
 998                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 999                 if (value < 0) {
1000                         ERROR(dev, "%s:%d Error!\n", __func__, __LINE__);
1001                         req->status = 0;
1002                 }
1003         }
1004         return value;
1005 }
1006
1007 static int printer_func_bind(struct usb_configuration *c,
1008                 struct usb_function *f)
1009 {
1010         struct usb_gadget *gadget = c->cdev->gadget;
1011         struct printer_dev *dev = func_to_printer(f);
1012         struct device *pdev;
1013         struct usb_composite_dev *cdev = c->cdev;
1014         struct usb_ep *in_ep;
1015         struct usb_ep *out_ep = NULL;
1016         struct usb_request *req;
1017         dev_t devt;
1018         int id;
1019         int ret;
1020         u32 i;
1021
1022         id = usb_interface_id(c, f);
1023         if (id < 0)
1024                 return id;
1025         intf_desc.bInterfaceNumber = id;
1026
1027         /* finish hookup to lower layer ... */
1028         dev->gadget = gadget;
1029
1030         /* all we really need is bulk IN/OUT */
1031         in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
1032         if (!in_ep) {
1033 autoconf_fail:
1034                 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
1035                         cdev->gadget->name);
1036                 return -ENODEV;
1037         }
1038         in_ep->driver_data = in_ep;     /* claim */
1039
1040         out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
1041         if (!out_ep)
1042                 goto autoconf_fail;
1043         out_ep->driver_data = out_ep;   /* claim */
1044
1045         /* assumes that all endpoints are dual-speed */
1046         hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1047         hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1048         ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1049         ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1050
1051         ret = usb_assign_descriptors(f, fs_printer_function,
1052                         hs_printer_function, ss_printer_function);
1053         if (ret)
1054                 return ret;
1055
1056         dev->in_ep = in_ep;
1057         dev->out_ep = out_ep;
1058
1059         ret = -ENOMEM;
1060         for (i = 0; i < dev->q_len; i++) {
1061                 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
1062                 if (!req)
1063                         goto fail_tx_reqs;
1064                 list_add(&req->list, &dev->tx_reqs);
1065         }
1066
1067         for (i = 0; i < dev->q_len; i++) {
1068                 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
1069                 if (!req)
1070                         goto fail_rx_reqs;
1071                 list_add(&req->list, &dev->rx_reqs);
1072         }
1073
1074         /* Setup the sysfs files for the printer gadget. */
1075         devt = MKDEV(major, dev->minor);
1076         pdev = device_create(usb_gadget_class, NULL, devt,
1077                                   NULL, "g_printer%d", dev->minor);
1078         if (IS_ERR(pdev)) {
1079                 ERROR(dev, "Failed to create device: g_printer\n");
1080                 ret = PTR_ERR(pdev);
1081                 goto fail_rx_reqs;
1082         }
1083
1084         /*
1085          * Register a character device as an interface to a user mode
1086          * program that handles the printer specific functionality.
1087          */
1088         cdev_init(&dev->printer_cdev, &printer_io_operations);
1089         dev->printer_cdev.owner = THIS_MODULE;
1090         ret = cdev_add(&dev->printer_cdev, devt, 1);
1091         if (ret) {
1092                 ERROR(dev, "Failed to open char device\n");
1093                 goto fail_cdev_add;
1094         }
1095
1096         return 0;
1097
1098 fail_cdev_add:
1099         device_destroy(usb_gadget_class, devt);
1100
1101 fail_rx_reqs:
1102         while (!list_empty(&dev->rx_reqs)) {
1103                 req = container_of(dev->rx_reqs.next, struct usb_request, list);
1104                 list_del(&req->list);
1105                 printer_req_free(dev->out_ep, req);
1106         }
1107
1108 fail_tx_reqs:
1109         while (!list_empty(&dev->tx_reqs)) {
1110                 req = container_of(dev->tx_reqs.next, struct usb_request, list);
1111                 list_del(&req->list);
1112                 printer_req_free(dev->in_ep, req);
1113         }
1114
1115         return ret;
1116
1117 }
1118
1119 static int printer_func_set_alt(struct usb_function *f,
1120                 unsigned intf, unsigned alt)
1121 {
1122         struct printer_dev *dev = func_to_printer(f);
1123         int ret = -ENOTSUPP;
1124
1125         if (!alt)
1126                 ret = set_interface(dev, intf);
1127
1128         return ret;
1129 }
1130
1131 static void printer_func_disable(struct usb_function *f)
1132 {
1133         struct printer_dev *dev = func_to_printer(f);
1134         unsigned long           flags;
1135
1136         DBG(dev, "%s\n", __func__);
1137
1138         spin_lock_irqsave(&dev->lock, flags);
1139         printer_reset_interface(dev);
1140         spin_unlock_irqrestore(&dev->lock, flags);
1141 }
1142
1143 static inline struct f_printer_opts
1144 *to_f_printer_opts(struct config_item *item)
1145 {
1146         return container_of(to_config_group(item), struct f_printer_opts,
1147                             func_inst.group);
1148 }
1149
1150 CONFIGFS_ATTR_STRUCT(f_printer_opts);
1151 CONFIGFS_ATTR_OPS(f_printer_opts);
1152
1153 static void printer_attr_release(struct config_item *item)
1154 {
1155         struct f_printer_opts *opts = to_f_printer_opts(item);
1156
1157         usb_put_function_instance(&opts->func_inst);
1158 }
1159
1160 static struct configfs_item_operations printer_item_ops = {
1161         .release        = printer_attr_release,
1162         .show_attribute = f_printer_opts_attr_show,
1163         .store_attribute = f_printer_opts_attr_store,
1164 };
1165
1166 static ssize_t f_printer_opts_pnp_string_show(struct f_printer_opts *opts,
1167                                               char *page)
1168 {
1169         int result;
1170
1171         mutex_lock(&opts->lock);
1172         result = strlcpy(page, opts->pnp_string + 2, PNP_STRING_LEN - 2);
1173         mutex_unlock(&opts->lock);
1174
1175         return result;
1176 }
1177
1178 static ssize_t f_printer_opts_pnp_string_store(struct f_printer_opts *opts,
1179                                                const char *page, size_t len)
1180 {
1181         int result, l;
1182
1183         mutex_lock(&opts->lock);
1184         result = strlcpy(opts->pnp_string + 2, page, PNP_STRING_LEN - 2);
1185         l = strlen(opts->pnp_string + 2) + 2;
1186         opts->pnp_string[0] = (l >> 8) & 0xFF;
1187         opts->pnp_string[1] = l & 0xFF;
1188         mutex_unlock(&opts->lock);
1189
1190         return result;
1191 }
1192
1193 static struct f_printer_opts_attribute f_printer_opts_pnp_string =
1194         __CONFIGFS_ATTR(pnp_string, S_IRUGO | S_IWUSR,
1195                         f_printer_opts_pnp_string_show,
1196                         f_printer_opts_pnp_string_store);
1197
1198 static ssize_t f_printer_opts_q_len_show(struct f_printer_opts *opts,
1199                                          char *page)
1200 {
1201         int result;
1202
1203         mutex_lock(&opts->lock);
1204         result = sprintf(page, "%d\n", opts->q_len);
1205         mutex_unlock(&opts->lock);
1206
1207         return result;
1208 }
1209
1210 static ssize_t f_printer_opts_q_len_store(struct f_printer_opts *opts,
1211                                           const char *page, size_t len)
1212 {
1213         int ret;
1214         u16 num;
1215
1216         mutex_lock(&opts->lock);
1217         if (opts->refcnt) {
1218                 ret = -EBUSY;
1219                 goto end;
1220         }
1221
1222         ret = kstrtou16(page, 0, &num);
1223         if (ret)
1224                 goto end;
1225
1226         opts->q_len = (unsigned)num;
1227         ret = len;
1228 end:
1229         mutex_unlock(&opts->lock);
1230         return ret;
1231 }
1232
1233 static struct f_printer_opts_attribute f_printer_opts_q_len =
1234         __CONFIGFS_ATTR(q_len, S_IRUGO | S_IWUSR, f_printer_opts_q_len_show,
1235                         f_printer_opts_q_len_store);
1236
1237 static struct configfs_attribute *printer_attrs[] = {
1238         &f_printer_opts_pnp_string.attr,
1239         &f_printer_opts_q_len.attr,
1240         NULL,
1241 };
1242
1243 static struct config_item_type printer_func_type = {
1244         .ct_item_ops    = &printer_item_ops,
1245         .ct_attrs       = printer_attrs,
1246         .ct_owner       = THIS_MODULE,
1247 };
1248
1249 static inline int gprinter_get_minor(void)
1250 {
1251         return ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL);
1252 }
1253
1254 static inline void gprinter_put_minor(int minor)
1255 {
1256         ida_simple_remove(&printer_ida, minor);
1257 }
1258
1259 static int gprinter_setup(int);
1260 static void gprinter_cleanup(void);
1261
1262 static void gprinter_free_inst(struct usb_function_instance *f)
1263 {
1264         struct f_printer_opts *opts;
1265
1266         opts = container_of(f, struct f_printer_opts, func_inst);
1267
1268         mutex_lock(&printer_ida_lock);
1269
1270         gprinter_put_minor(opts->minor);
1271         if (idr_is_empty(&printer_ida.idr))
1272                 gprinter_cleanup();
1273
1274         mutex_unlock(&printer_ida_lock);
1275
1276         kfree(opts);
1277 }
1278
1279 static struct usb_function_instance *gprinter_alloc_inst(void)
1280 {
1281         struct f_printer_opts *opts;
1282         struct usb_function_instance *ret;
1283         int status = 0;
1284
1285         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1286         if (!opts)
1287                 return ERR_PTR(-ENOMEM);
1288
1289         mutex_init(&opts->lock);
1290         opts->func_inst.free_func_inst = gprinter_free_inst;
1291         ret = &opts->func_inst;
1292
1293         mutex_lock(&printer_ida_lock);
1294
1295         if (idr_is_empty(&printer_ida.idr)) {
1296                 status = gprinter_setup(PRINTER_MINORS);
1297                 if (status) {
1298                         ret = ERR_PTR(status);
1299                         kfree(opts);
1300                         goto unlock;
1301                 }
1302         }
1303
1304         opts->minor = gprinter_get_minor();
1305         if (opts->minor < 0) {
1306                 ret = ERR_PTR(opts->minor);
1307                 kfree(opts);
1308                 if (idr_is_empty(&printer_ida.idr))
1309                         gprinter_cleanup();
1310                 goto unlock;
1311         }
1312         config_group_init_type_name(&opts->func_inst.group, "",
1313                                     &printer_func_type);
1314
1315 unlock:
1316         mutex_unlock(&printer_ida_lock);
1317         return ret;
1318 }
1319
1320 static void gprinter_free(struct usb_function *f)
1321 {
1322         struct printer_dev *dev = func_to_printer(f);
1323         struct f_printer_opts *opts;
1324
1325         opts = container_of(f->fi, struct f_printer_opts, func_inst);
1326         kfree(dev);
1327         mutex_lock(&opts->lock);
1328         --opts->refcnt;
1329         mutex_unlock(&opts->lock);
1330 }
1331
1332 static void printer_func_unbind(struct usb_configuration *c,
1333                 struct usb_function *f)
1334 {
1335         struct printer_dev      *dev;
1336         struct usb_request      *req;
1337
1338         dev = func_to_printer(f);
1339
1340         device_destroy(usb_gadget_class, MKDEV(major, dev->minor));
1341
1342         /* Remove Character Device */
1343         cdev_del(&dev->printer_cdev);
1344
1345         /* we must already have been disconnected ... no i/o may be active */
1346         WARN_ON(!list_empty(&dev->tx_reqs_active));
1347         WARN_ON(!list_empty(&dev->rx_reqs_active));
1348
1349         /* Free all memory for this driver. */
1350         while (!list_empty(&dev->tx_reqs)) {
1351                 req = container_of(dev->tx_reqs.next, struct usb_request,
1352                                 list);
1353                 list_del(&req->list);
1354                 printer_req_free(dev->in_ep, req);
1355         }
1356
1357         if (dev->current_rx_req != NULL)
1358                 printer_req_free(dev->out_ep, dev->current_rx_req);
1359
1360         while (!list_empty(&dev->rx_reqs)) {
1361                 req = container_of(dev->rx_reqs.next,
1362                                 struct usb_request, list);
1363                 list_del(&req->list);
1364                 printer_req_free(dev->out_ep, req);
1365         }
1366
1367         while (!list_empty(&dev->rx_buffers)) {
1368                 req = container_of(dev->rx_buffers.next,
1369                                 struct usb_request, list);
1370                 list_del(&req->list);
1371                 printer_req_free(dev->out_ep, req);
1372         }
1373         usb_free_all_descriptors(f);
1374 }
1375
1376 static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
1377 {
1378         struct printer_dev      *dev;
1379         struct f_printer_opts   *opts;
1380
1381         opts = container_of(fi, struct f_printer_opts, func_inst);
1382
1383         mutex_lock(&opts->lock);
1384         if (opts->minor >= minors) {
1385                 mutex_unlock(&opts->lock);
1386                 return ERR_PTR(-ENOENT);
1387         }
1388
1389         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1390         if (!dev) {
1391                 mutex_unlock(&opts->lock);
1392                 return ERR_PTR(-ENOMEM);
1393         }
1394
1395         ++opts->refcnt;
1396         dev->minor = opts->minor;
1397         dev->pnp_string = opts->pnp_string;
1398         dev->q_len = opts->q_len;
1399         mutex_unlock(&opts->lock);
1400
1401         dev->function.name = "printer";
1402         dev->function.bind = printer_func_bind;
1403         dev->function.setup = printer_func_setup;
1404         dev->function.unbind = printer_func_unbind;
1405         dev->function.set_alt = printer_func_set_alt;
1406         dev->function.disable = printer_func_disable;
1407         dev->function.req_match = gprinter_req_match;
1408         dev->function.free_func = gprinter_free;
1409
1410         INIT_LIST_HEAD(&dev->tx_reqs);
1411         INIT_LIST_HEAD(&dev->rx_reqs);
1412         INIT_LIST_HEAD(&dev->rx_buffers);
1413         INIT_LIST_HEAD(&dev->tx_reqs_active);
1414         INIT_LIST_HEAD(&dev->rx_reqs_active);
1415
1416         spin_lock_init(&dev->lock);
1417         mutex_init(&dev->lock_printer_io);
1418         init_waitqueue_head(&dev->rx_wait);
1419         init_waitqueue_head(&dev->tx_wait);
1420         init_waitqueue_head(&dev->tx_flush_wait);
1421
1422         dev->interface = -1;
1423         dev->printer_cdev_open = 0;
1424         dev->printer_status = PRINTER_NOT_ERROR;
1425         dev->current_rx_req = NULL;
1426         dev->current_rx_bytes = 0;
1427         dev->current_rx_buf = NULL;
1428
1429         return &dev->function;
1430 }
1431
1432 DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc);
1433 MODULE_LICENSE("GPL");
1434 MODULE_AUTHOR("Craig Nadler");
1435
1436 static int gprinter_setup(int count)
1437 {
1438         int status;
1439         dev_t devt;
1440
1441         usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
1442         if (IS_ERR(usb_gadget_class)) {
1443                 status = PTR_ERR(usb_gadget_class);
1444                 usb_gadget_class = NULL;
1445                 pr_err("unable to create usb_gadget class %d\n", status);
1446                 return status;
1447         }
1448
1449         status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget");
1450         if (status) {
1451                 pr_err("alloc_chrdev_region %d\n", status);
1452                 class_destroy(usb_gadget_class);
1453                 usb_gadget_class = NULL;
1454                 return status;
1455         }
1456
1457         major = MAJOR(devt);
1458         minors = count;
1459
1460         return status;
1461 }
1462
1463 static void gprinter_cleanup(void)
1464 {
1465         if (major) {
1466                 unregister_chrdev_region(MKDEV(major, 0), minors);
1467                 major = minors = 0;
1468         }
1469         class_destroy(usb_gadget_class);
1470         usb_gadget_class = NULL;
1471 }