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         unsigned long   flags;
 808
 809         if (dev->interface < 0)
 810                 return;
 811
 812         DBG(dev, "%s\n", __func__);
 813
 814         if (dev->in_ep->desc)
 815                 usb_ep_disable(dev->in_ep);
 816
 817         if (dev->out_ep->desc)
 818                 usb_ep_disable(dev->out_ep);
 819
 820         spin_lock_irqsave(&dev->lock, flags);
 821         dev->in_ep->desc = NULL;
 822         dev->out_ep->desc = NULL;
 823         dev->interface = -1;
 824         spin_unlock_irqrestore(&dev->lock, flags);
 825 }
 826
 827 /* Change our operational Interface. */
 828 static int set_interface(struct printer_dev *dev, unsigned number)
 829 {
 830         int                     result = 0;
 831
 832         /* Free the current interface */
 833         printer_reset_interface(dev);
 834
 835         result = set_printer_interface(dev);
 836         if (result)
 837                 printer_reset_interface(dev);
 838         else
 839                 dev->interface = number;
 840
 841         if (!result)
 842                 INFO(dev, "Using interface %x\n", number);
 843
 844         return result;
 845 }
 846
 847 static void printer_soft_reset(struct printer_dev *dev)
 848 {
 849         struct usb_request      *req;
 850
 851         INFO(dev, "Received Printer Reset Request\n");
 852
 853         if (usb_ep_disable(dev->in_ep))
 854                 DBG(dev, "Failed to disable USB in_ep\n");
 855         if (usb_ep_disable(dev->out_ep))
 856                 DBG(dev, "Failed to disable USB out_ep\n");
 857
 858         if (dev->current_rx_req != NULL) {
 859                 list_add(&dev->current_rx_req->list, &dev->rx_reqs);
 860                 dev->current_rx_req = NULL;
 861         }
 862         dev->current_rx_bytes = 0;
 863         dev->current_rx_buf = NULL;
 864         dev->reset_printer = 1;
 865
 866         while (likely(!(list_empty(&dev->rx_buffers)))) {
 867                 req = container_of(dev->rx_buffers.next, struct usb_request,
 868                                 list);
 869                 list_del_init(&req->list);
 870                 list_add(&req->list, &dev->rx_reqs);
 871         }
 872
 873         while (likely(!(list_empty(&dev->rx_reqs_active)))) {
 874                 req = container_of(dev->rx_buffers.next, struct usb_request,
 875                                 list);
 876                 list_del_init(&req->list);
 877                 list_add(&req->list, &dev->rx_reqs);
 878         }
 879
 880         while (likely(!(list_empty(&dev->tx_reqs_active)))) {
 881                 req = container_of(dev->tx_reqs_active.next,
 882                                 struct usb_request, list);
 883                 list_del_init(&req->list);
 884                 list_add(&req->list, &dev->tx_reqs);
 885         }
 886
 887         if (usb_ep_enable(dev->in_ep))
 888                 DBG(dev, "Failed to enable USB in_ep\n");
 889         if (usb_ep_enable(dev->out_ep))
 890                 DBG(dev, "Failed to enable USB out_ep\n");
 891
 892         wake_up_interruptible(&dev->rx_wait);
 893         wake_up_interruptible(&dev->tx_wait);
 894         wake_up_interruptible(&dev->tx_flush_wait);
 895 }
 896
 897 /*-------------------------------------------------------------------------*/
 898
 899 static bool gprinter_req_match(struct usb_function *f,
 900                                const struct usb_ctrlrequest *ctrl)
 901 {
 902         struct printer_dev      *dev = func_to_printer(f);
 903         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 904         u16                     w_value = le16_to_cpu(ctrl->wValue);
 905         u16                     w_length = le16_to_cpu(ctrl->wLength);
 906
 907         if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE ||
 908             (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
 909                 return false;
 910
 911         switch (ctrl->bRequest) {
 912         case GET_DEVICE_ID:
 913                 w_index >>= 8;
 914                 if (w_length <= PNP_STRING_LEN &&
 915                     (USB_DIR_IN & ctrl->bRequestType))
 916                         break;
 917                 return false;
 918         case GET_PORT_STATUS:
 919                 if (!w_value && w_length == 1 &&
 920                     (USB_DIR_IN & ctrl->bRequestType))
 921                         break;
 922                 return false;
 923         case SOFT_RESET:
 924                 if (!w_value && !w_length &&
 925                    !(USB_DIR_IN & ctrl->bRequestType))
 926                         break;
 927                 /* fall through */
 928         default:
 929                 return false;
 930         }
 931         return w_index == dev->interface;
 932 }
 933
 934 /*
 935  * The setup() callback implements all the ep0 functionality that's not
 936  * handled lower down.
 937  */
 938 static int printer_func_setup(struct usb_function *f,
 939                 const struct usb_ctrlrequest *ctrl)
 940 {
 941         struct printer_dev *dev = func_to_printer(f);
 942         struct usb_composite_dev *cdev = f->config->cdev;
 943         struct usb_request      *req = cdev->req;
 944         int                     value = -EOPNOTSUPP;
 945         u16                     wIndex = le16_to_cpu(ctrl->wIndex);
 946         u16                     wValue = le16_to_cpu(ctrl->wValue);
 947         u16                     wLength = le16_to_cpu(ctrl->wLength);
 948
 949         DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
 950                 ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
 951
 952         switch (ctrl->bRequestType&USB_TYPE_MASK) {
 953         case USB_TYPE_CLASS:
 954                 switch (ctrl->bRequest) {
 955                 case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */
 956                         /* Only one printer interface is supported. */
 957                         if ((wIndex>>8) != dev->interface)
 958                                 break;
 959
 960                         value = (dev->pnp_string[0] << 8) | dev->pnp_string[1];
 961                         memcpy(req->buf, dev->pnp_string, value);
 962                         DBG(dev, "1284 PNP String: %x %s\n", value,
 963                                         &dev->pnp_string[2]);
 964                         break;
 965
 966                 case GET_PORT_STATUS: /* Get Port Status */
 967                         /* Only one printer interface is supported. */
 968                         if (wIndex != dev->interface)
 969                                 break;
 970
 971                         *(u8 *)req->buf = dev->printer_status;
 972                         value = min_t(u16, wLength, 1);
 973                         break;
 974
 975                 case SOFT_RESET: /* Soft Reset */
 976                         /* Only one printer interface is supported. */
 977                         if (wIndex != dev->interface)
 978                                 break;
 979
 980                         printer_soft_reset(dev);
 981
 982                         value = 0;
 983                         break;
 984
 985                 default:
 986                         goto unknown;
 987                 }
 988                 break;
 989
 990         default:
 991 unknown:
 992                 VDBG(dev,
 993                         "unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
 994                         ctrl->bRequestType, ctrl->bRequest,
 995                         wValue, wIndex, wLength);
 996                 break;
 997         }
 998         /* host either stalls (value < 0) or reports success */
 999         if (value >= 0) {
1000                 req->length = value;
1001                 req->zero = value < wLength;
1002                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
1003                 if (value < 0) {
1004                         ERROR(dev, "%s:%d Error!\n", __func__, __LINE__);
1005                         req->status = 0;
1006                 }
1007         }
1008         return value;
1009 }
1010
1011 static int printer_func_bind(struct usb_configuration *c,
1012                 struct usb_function *f)
1013 {
1014         struct usb_gadget *gadget = c->cdev->gadget;
1015         struct printer_dev *dev = func_to_printer(f);
1016         struct device *pdev;
1017         struct usb_composite_dev *cdev = c->cdev;
1018         struct usb_ep *in_ep;
1019         struct usb_ep *out_ep = NULL;
1020         struct usb_request *req;
1021         dev_t devt;
1022         int id;
1023         int ret;
1024         u32 i;
1025
1026         id = usb_interface_id(c, f);
1027         if (id < 0)
1028                 return id;
1029         intf_desc.bInterfaceNumber = id;
1030
1031         /* finish hookup to lower layer ... */
1032         dev->gadget = gadget;
1033
1034         /* all we really need is bulk IN/OUT */
1035         in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
1036         if (!in_ep) {
1037 autoconf_fail:
1038                 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
1039                         cdev->gadget->name);
1040                 return -ENODEV;
1041         }
1042         in_ep->driver_data = in_ep;     /* claim */
1043
1044         out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
1045         if (!out_ep)
1046                 goto autoconf_fail;
1047         out_ep->driver_data = out_ep;   /* claim */
1048
1049         /* assumes that all endpoints are dual-speed */
1050         hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1051         hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1052         ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1053         ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1054
1055         ret = usb_assign_descriptors(f, fs_printer_function,
1056                         hs_printer_function, ss_printer_function);
1057         if (ret)
1058                 return ret;
1059
1060         dev->in_ep = in_ep;
1061         dev->out_ep = out_ep;
1062
1063         ret = -ENOMEM;
1064         for (i = 0; i < dev->q_len; i++) {
1065                 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
1066                 if (!req)
1067                         goto fail_tx_reqs;
1068                 list_add(&req->list, &dev->tx_reqs);
1069         }
1070
1071         for (i = 0; i < dev->q_len; i++) {
1072                 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
1073                 if (!req)
1074                         goto fail_rx_reqs;
1075                 list_add(&req->list, &dev->rx_reqs);
1076         }
1077
1078         /* Setup the sysfs files for the printer gadget. */
1079         devt = MKDEV(major, dev->minor);
1080         pdev = device_create(usb_gadget_class, NULL, devt,
1081                                   NULL, "g_printer%d", dev->minor);
1082         if (IS_ERR(pdev)) {
1083                 ERROR(dev, "Failed to create device: g_printer\n");
1084                 ret = PTR_ERR(pdev);
1085                 goto fail_rx_reqs;
1086         }
1087
1088         /*
1089          * Register a character device as an interface to a user mode
1090          * program that handles the printer specific functionality.
1091          */
1092         cdev_init(&dev->printer_cdev, &printer_io_operations);
1093         dev->printer_cdev.owner = THIS_MODULE;
1094         ret = cdev_add(&dev->printer_cdev, devt, 1);
1095         if (ret) {
1096                 ERROR(dev, "Failed to open char device\n");
1097                 goto fail_cdev_add;
1098         }
1099
1100         return 0;
1101
1102 fail_cdev_add:
1103         device_destroy(usb_gadget_class, devt);
1104
1105 fail_rx_reqs:
1106         while (!list_empty(&dev->rx_reqs)) {
1107                 req = container_of(dev->rx_reqs.next, struct usb_request, list);
1108                 list_del(&req->list);
1109                 printer_req_free(dev->out_ep, req);
1110         }
1111
1112 fail_tx_reqs:
1113         while (!list_empty(&dev->tx_reqs)) {
1114                 req = container_of(dev->tx_reqs.next, struct usb_request, list);
1115                 list_del(&req->list);
1116                 printer_req_free(dev->in_ep, req);
1117         }
1118
1119         return ret;
1120
1121 }
1122
1123 static int printer_func_set_alt(struct usb_function *f,
1124                 unsigned intf, unsigned alt)
1125 {
1126         struct printer_dev *dev = func_to_printer(f);
1127         int ret = -ENOTSUPP;
1128
1129         if (!alt)
1130                 ret = set_interface(dev, intf);
1131
1132         return ret;
1133 }
1134
1135 static void printer_func_disable(struct usb_function *f)
1136 {
1137         struct printer_dev *dev = func_to_printer(f);
1138
1139         DBG(dev, "%s\n", __func__);
1140
1141         printer_reset_interface(dev);
1142 }
1143
1144 static inline struct f_printer_opts
1145 *to_f_printer_opts(struct config_item *item)
1146 {
1147         return container_of(to_config_group(item), struct f_printer_opts,
1148                             func_inst.group);
1149 }
1150
1151 CONFIGFS_ATTR_STRUCT(f_printer_opts);
1152 CONFIGFS_ATTR_OPS(f_printer_opts);
1153
1154 static void printer_attr_release(struct config_item *item)
1155 {
1156         struct f_printer_opts *opts = to_f_printer_opts(item);
1157
1158         usb_put_function_instance(&opts->func_inst);
1159 }
1160
1161 static struct configfs_item_operations printer_item_ops = {
1162         .release        = printer_attr_release,
1163         .show_attribute = f_printer_opts_attr_show,
1164         .store_attribute = f_printer_opts_attr_store,
1165 };
1166
1167 static ssize_t f_printer_opts_pnp_string_show(struct f_printer_opts *opts,
1168                                               char *page)
1169 {
1170         int result;
1171
1172         mutex_lock(&opts->lock);
1173         result = strlcpy(page, opts->pnp_string + 2, PNP_STRING_LEN - 2);
1174         mutex_unlock(&opts->lock);
1175
1176         return result;
1177 }
1178
1179 static ssize_t f_printer_opts_pnp_string_store(struct f_printer_opts *opts,
1180                                                const char *page, size_t len)
1181 {
1182         int result, l;
1183
1184         mutex_lock(&opts->lock);
1185         result = strlcpy(opts->pnp_string + 2, page, PNP_STRING_LEN - 2);
1186         l = strlen(opts->pnp_string + 2) + 2;
1187         opts->pnp_string[0] = (l >> 8) & 0xFF;
1188         opts->pnp_string[1] = l & 0xFF;
1189         mutex_unlock(&opts->lock);
1190
1191         return result;
1192 }
1193
1194 static struct f_printer_opts_attribute f_printer_opts_pnp_string =
1195         __CONFIGFS_ATTR(pnp_string, S_IRUGO | S_IWUSR,
1196                         f_printer_opts_pnp_string_show,
1197                         f_printer_opts_pnp_string_store);
1198
1199 static ssize_t f_printer_opts_q_len_show(struct f_printer_opts *opts,
1200                                          char *page)
1201 {
1202         int result;
1203
1204         mutex_lock(&opts->lock);
1205         result = sprintf(page, "%d\n", opts->q_len);
1206         mutex_unlock(&opts->lock);
1207
1208         return result;
1209 }
1210
1211 static ssize_t f_printer_opts_q_len_store(struct f_printer_opts *opts,
1212                                           const char *page, size_t len)
1213 {
1214         int ret;
1215         u16 num;
1216
1217         mutex_lock(&opts->lock);
1218         if (opts->refcnt) {
1219                 ret = -EBUSY;
1220                 goto end;
1221         }
1222
1223         ret = kstrtou16(page, 0, &num);
1224         if (ret)
1225                 goto end;
1226
1227         opts->q_len = (unsigned)num;
1228         ret = len;
1229 end:
1230         mutex_unlock(&opts->lock);
1231         return ret;
1232 }
1233
1234 static struct f_printer_opts_attribute f_printer_opts_q_len =
1235         __CONFIGFS_ATTR(q_len, S_IRUGO | S_IWUSR, f_printer_opts_q_len_show,
1236                         f_printer_opts_q_len_store);
1237
1238 static struct configfs_attribute *printer_attrs[] = {
1239         &f_printer_opts_pnp_string.attr,
1240         &f_printer_opts_q_len.attr,
1241         NULL,
1242 };
1243
1244 static struct config_item_type printer_func_type = {
1245         .ct_item_ops    = &printer_item_ops,
1246         .ct_attrs       = printer_attrs,
1247         .ct_owner       = THIS_MODULE,
1248 };
1249
1250 static inline int gprinter_get_minor(void)
1251 {
1252         int ret;
1253
1254         ret = ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL);
1255         if (ret >= PRINTER_MINORS) {
1256                 ida_simple_remove(&printer_ida, ret);
1257                 ret = -ENODEV;
1258         }
1259
1260         return ret;
1261 }
1262
1263 static inline void gprinter_put_minor(int minor)
1264 {
1265         ida_simple_remove(&printer_ida, minor);
1266 }
1267
1268 static int gprinter_setup(int);
1269 static void gprinter_cleanup(void);
1270
1271 static void gprinter_free_inst(struct usb_function_instance *f)
1272 {
1273         struct f_printer_opts *opts;
1274
1275         opts = container_of(f, struct f_printer_opts, func_inst);
1276
1277         mutex_lock(&printer_ida_lock);
1278
1279         gprinter_put_minor(opts->minor);
1280         if (idr_is_empty(&printer_ida.idr))
1281                 gprinter_cleanup();
1282
1283         mutex_unlock(&printer_ida_lock);
1284
1285         kfree(opts);
1286 }
1287
1288 static struct usb_function_instance *gprinter_alloc_inst(void)
1289 {
1290         struct f_printer_opts *opts;
1291         struct usb_function_instance *ret;
1292         int status = 0;
1293
1294         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1295         if (!opts)
1296                 return ERR_PTR(-ENOMEM);
1297
1298         mutex_init(&opts->lock);
1299         opts->func_inst.free_func_inst = gprinter_free_inst;
1300         ret = &opts->func_inst;
1301
1302         mutex_lock(&printer_ida_lock);
1303
1304         if (idr_is_empty(&printer_ida.idr)) {
1305                 status = gprinter_setup(PRINTER_MINORS);
1306                 if (status) {
1307                         ret = ERR_PTR(status);
1308                         kfree(opts);
1309                         goto unlock;
1310                 }
1311         }
1312
1313         opts->minor = gprinter_get_minor();
1314         if (opts->minor < 0) {
1315                 ret = ERR_PTR(opts->minor);
1316                 kfree(opts);
1317                 if (idr_is_empty(&printer_ida.idr))
1318                         gprinter_cleanup();
1319                 goto unlock;
1320         }
1321         config_group_init_type_name(&opts->func_inst.group, "",
1322                                     &printer_func_type);
1323
1324 unlock:
1325         mutex_unlock(&printer_ida_lock);
1326         return ret;
1327 }
1328
1329 static void gprinter_free(struct usb_function *f)
1330 {
1331         struct printer_dev *dev = func_to_printer(f);
1332         struct f_printer_opts *opts;
1333
1334         opts = container_of(f->fi, struct f_printer_opts, func_inst);
1335         kfree(dev);
1336         mutex_lock(&opts->lock);
1337         --opts->refcnt;
1338         mutex_unlock(&opts->lock);
1339 }
1340
1341 static void printer_func_unbind(struct usb_configuration *c,
1342                 struct usb_function *f)
1343 {
1344         struct printer_dev      *dev;
1345         struct usb_request      *req;
1346
1347         dev = func_to_printer(f);
1348
1349         device_destroy(usb_gadget_class, MKDEV(major, dev->minor));
1350
1351         /* Remove Character Device */
1352         cdev_del(&dev->printer_cdev);
1353
1354         /* we must already have been disconnected ... no i/o may be active */
1355         WARN_ON(!list_empty(&dev->tx_reqs_active));
1356         WARN_ON(!list_empty(&dev->rx_reqs_active));
1357
1358         /* Free all memory for this driver. */
1359         while (!list_empty(&dev->tx_reqs)) {
1360                 req = container_of(dev->tx_reqs.next, struct usb_request,
1361                                 list);
1362                 list_del(&req->list);
1363                 printer_req_free(dev->in_ep, req);
1364         }
1365
1366         if (dev->current_rx_req != NULL)
1367                 printer_req_free(dev->out_ep, dev->current_rx_req);
1368
1369         while (!list_empty(&dev->rx_reqs)) {
1370                 req = container_of(dev->rx_reqs.next,
1371                                 struct usb_request, list);
1372                 list_del(&req->list);
1373                 printer_req_free(dev->out_ep, req);
1374         }
1375
1376         while (!list_empty(&dev->rx_buffers)) {
1377                 req = container_of(dev->rx_buffers.next,
1378                                 struct usb_request, list);
1379                 list_del(&req->list);
1380                 printer_req_free(dev->out_ep, req);
1381         }
1382         usb_free_all_descriptors(f);
1383 }
1384
1385 static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
1386 {
1387         struct printer_dev      *dev;
1388         struct f_printer_opts   *opts;
1389
1390         opts = container_of(fi, struct f_printer_opts, func_inst);
1391
1392         mutex_lock(&opts->lock);
1393         if (opts->minor >= minors) {
1394                 mutex_unlock(&opts->lock);
1395                 return ERR_PTR(-ENOENT);
1396         }
1397
1398         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1399         if (!dev) {
1400                 mutex_unlock(&opts->lock);
1401                 return ERR_PTR(-ENOMEM);
1402         }
1403
1404         ++opts->refcnt;
1405         dev->minor = opts->minor;
1406         dev->pnp_string = opts->pnp_string;
1407         dev->q_len = opts->q_len;
1408         mutex_unlock(&opts->lock);
1409
1410         dev->function.name = "printer";
1411         dev->function.bind = printer_func_bind;
1412         dev->function.setup = printer_func_setup;
1413         dev->function.unbind = printer_func_unbind;
1414         dev->function.set_alt = printer_func_set_alt;
1415         dev->function.disable = printer_func_disable;
1416         dev->function.req_match = gprinter_req_match;
1417         dev->function.free_func = gprinter_free;
1418
1419         INIT_LIST_HEAD(&dev->tx_reqs);
1420         INIT_LIST_HEAD(&dev->rx_reqs);
1421         INIT_LIST_HEAD(&dev->rx_buffers);
1422         INIT_LIST_HEAD(&dev->tx_reqs_active);
1423         INIT_LIST_HEAD(&dev->rx_reqs_active);
1424
1425         spin_lock_init(&dev->lock);
1426         mutex_init(&dev->lock_printer_io);
1427         init_waitqueue_head(&dev->rx_wait);
1428         init_waitqueue_head(&dev->tx_wait);
1429         init_waitqueue_head(&dev->tx_flush_wait);
1430
1431         dev->interface = -1;
1432         dev->printer_cdev_open = 0;
1433         dev->printer_status = PRINTER_NOT_ERROR;
1434         dev->current_rx_req = NULL;
1435         dev->current_rx_bytes = 0;
1436         dev->current_rx_buf = NULL;
1437
1438         return &dev->function;
1439 }
1440
1441 DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc);
1442 MODULE_LICENSE("GPL");
1443 MODULE_AUTHOR("Craig Nadler");
1444
1445 static int gprinter_setup(int count)
1446 {
1447         int status;
1448         dev_t devt;
1449
1450         usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
1451         if (IS_ERR(usb_gadget_class)) {
1452                 status = PTR_ERR(usb_gadget_class);
1453                 usb_gadget_class = NULL;
1454                 pr_err("unable to create usb_gadget class %d\n", status);
1455                 return status;
1456         }
1457
1458         status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget");
1459         if (status) {
1460                 pr_err("alloc_chrdev_region %d\n", status);
1461                 class_destroy(usb_gadget_class);
1462                 usb_gadget_class = NULL;
1463                 return status;
1464         }
1465
1466         major = MAJOR(devt);
1467         minors = count;
1468
1469         return status;
1470 }
1471
1472 static void gprinter_cleanup(void)
1473 {
1474         if (major) {
1475                 unregister_chrdev_region(MKDEV(major, 0), minors);
1476                 major = minors = 0;
1477         }
1478         class_destroy(usb_gadget_class);
1479         usb_gadget_class = NULL;
1480 }