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_descriptor_header *hs_printer_function[] = {
 165         (struct usb_descriptor_header *) &intf_desc,
 166         (struct usb_descriptor_header *) &hs_ep_in_desc,
 167         (struct usb_descriptor_header *) &hs_ep_out_desc,
 168         NULL
 169 };
 170
 171 /*
 172  * Added endpoint descriptors for 3.0 devices
 173  */
 174
 175 static struct usb_endpoint_descriptor ss_ep_in_desc = {
 176         .bLength =              USB_DT_ENDPOINT_SIZE,
 177         .bDescriptorType =      USB_DT_ENDPOINT,
 178         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 179         .wMaxPacketSize =       cpu_to_le16(1024),
 180 };
 181
 182 static struct usb_ss_ep_comp_descriptor ss_ep_in_comp_desc = {
 183         .bLength =              sizeof(ss_ep_in_comp_desc),
 184         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 185 };
 186
 187 static struct usb_endpoint_descriptor ss_ep_out_desc = {
 188         .bLength =              USB_DT_ENDPOINT_SIZE,
 189         .bDescriptorType =      USB_DT_ENDPOINT,
 190         .bmAttributes =         USB_ENDPOINT_XFER_BULK,
 191         .wMaxPacketSize =       cpu_to_le16(1024),
 192 };
 193
 194 static struct usb_ss_ep_comp_descriptor ss_ep_out_comp_desc = {
 195         .bLength =              sizeof(ss_ep_out_comp_desc),
 196         .bDescriptorType =      USB_DT_SS_ENDPOINT_COMP,
 197 };
 198
 199 static struct usb_descriptor_header *ss_printer_function[] = {
 200         (struct usb_descriptor_header *) &intf_desc,
 201         (struct usb_descriptor_header *) &ss_ep_in_desc,
 202         (struct usb_descriptor_header *) &ss_ep_in_comp_desc,
 203         (struct usb_descriptor_header *) &ss_ep_out_desc,
 204         (struct usb_descriptor_header *) &ss_ep_out_comp_desc,
 205         NULL
 206 };
 207
 208 /* maxpacket and other transfer characteristics vary by speed. */
 209 static inline struct usb_endpoint_descriptor *ep_desc(struct usb_gadget *gadget,
 210                                         struct usb_endpoint_descriptor *fs,
 211                                         struct usb_endpoint_descriptor *hs,
 212                                         struct usb_endpoint_descriptor *ss)
 213 {
 214         switch (gadget->speed) {
 215         case USB_SPEED_SUPER:
 216                 return ss;
 217         case USB_SPEED_HIGH:
 218                 return hs;
 219         default:
 220                 return fs;
 221         }
 222 }
 223
 224 /*-------------------------------------------------------------------------*/
 225
 226 static struct usb_request *
 227 printer_req_alloc(struct usb_ep *ep, unsigned len, gfp_t gfp_flags)
 228 {
 229         struct usb_request      *req;
 230
 231         req = usb_ep_alloc_request(ep, gfp_flags);
 232
 233         if (req != NULL) {
 234                 req->length = len;
 235                 req->buf = kmalloc(len, gfp_flags);
 236                 if (req->buf == NULL) {
 237                         usb_ep_free_request(ep, req);
 238                         return NULL;
 239                 }
 240         }
 241
 242         return req;
 243 }
 244
 245 static void
 246 printer_req_free(struct usb_ep *ep, struct usb_request *req)
 247 {
 248         if (ep != NULL && req != NULL) {
 249                 kfree(req->buf);
 250                 usb_ep_free_request(ep, req);
 251         }
 252 }
 253
 254 /*-------------------------------------------------------------------------*/
 255
 256 static void rx_complete(struct usb_ep *ep, struct usb_request *req)
 257 {
 258         struct printer_dev      *dev = ep->driver_data;
 259         int                     status = req->status;
 260         unsigned long           flags;
 261
 262         spin_lock_irqsave(&dev->lock, flags);
 263
 264         list_del_init(&req->list);      /* Remode from Active List */
 265
 266         switch (status) {
 267
 268         /* normal completion */
 269         case 0:
 270                 if (req->actual > 0) {
 271                         list_add_tail(&req->list, &dev->rx_buffers);
 272                         DBG(dev, "G_Printer : rx length %d\n", req->actual);
 273                 } else {
 274                         list_add(&req->list, &dev->rx_reqs);
 275                 }
 276                 break;
 277
 278         /* software-driven interface shutdown */
 279         case -ECONNRESET:               /* unlink */
 280         case -ESHUTDOWN:                /* disconnect etc */
 281                 VDBG(dev, "rx shutdown, code %d\n", status);
 282                 list_add(&req->list, &dev->rx_reqs);
 283                 break;
 284
 285         /* for hardware automagic (such as pxa) */
 286         case -ECONNABORTED:             /* endpoint reset */
 287                 DBG(dev, "rx %s reset\n", ep->name);
 288                 list_add(&req->list, &dev->rx_reqs);
 289                 break;
 290
 291         /* data overrun */
 292         case -EOVERFLOW:
 293                 /* FALLTHROUGH */
 294
 295         default:
 296                 DBG(dev, "rx status %d\n", status);
 297                 list_add(&req->list, &dev->rx_reqs);
 298                 break;
 299         }
 300
 301         wake_up_interruptible(&dev->rx_wait);
 302         spin_unlock_irqrestore(&dev->lock, flags);
 303 }
 304
 305 static void tx_complete(struct usb_ep *ep, struct usb_request *req)
 306 {
 307         struct printer_dev      *dev = ep->driver_data;
 308
 309         switch (req->status) {
 310         default:
 311                 VDBG(dev, "tx err %d\n", req->status);
 312                 /* FALLTHROUGH */
 313         case -ECONNRESET:               /* unlink */
 314         case -ESHUTDOWN:                /* disconnect etc */
 315                 break;
 316         case 0:
 317                 break;
 318         }
 319
 320         spin_lock(&dev->lock);
 321         /* Take the request struct off the active list and put it on the
 322          * free list.
 323          */
 324         list_del_init(&req->list);
 325         list_add(&req->list, &dev->tx_reqs);
 326         wake_up_interruptible(&dev->tx_wait);
 327         if (likely(list_empty(&dev->tx_reqs_active)))
 328                 wake_up_interruptible(&dev->tx_flush_wait);
 329
 330         spin_unlock(&dev->lock);
 331 }
 332
 333 /*-------------------------------------------------------------------------*/
 334
 335 static int
 336 printer_open(struct inode *inode, struct file *fd)
 337 {
 338         struct printer_dev      *dev;
 339         unsigned long           flags;
 340         int                     ret = -EBUSY;
 341
 342         dev = container_of(inode->i_cdev, struct printer_dev, printer_cdev);
 343
 344         spin_lock_irqsave(&dev->lock, flags);
 345
 346         if (!dev->printer_cdev_open) {
 347                 dev->printer_cdev_open = 1;
 348                 fd->private_data = dev;
 349                 ret = 0;
 350                 /* Change the printer status to show that it's on-line. */
 351                 dev->printer_status |= PRINTER_SELECTED;
 352         }
 353
 354         spin_unlock_irqrestore(&dev->lock, flags);
 355
 356         DBG(dev, "printer_open returned %x\n", ret);
 357         return ret;
 358 }
 359
 360 static int
 361 printer_close(struct inode *inode, struct file *fd)
 362 {
 363         struct printer_dev      *dev = fd->private_data;
 364         unsigned long           flags;
 365
 366         spin_lock_irqsave(&dev->lock, flags);
 367         dev->printer_cdev_open = 0;
 368         fd->private_data = NULL;
 369         /* Change printer status to show that the printer is off-line. */
 370         dev->printer_status &= ~PRINTER_SELECTED;
 371         spin_unlock_irqrestore(&dev->lock, flags);
 372
 373         DBG(dev, "printer_close\n");
 374
 375         return 0;
 376 }
 377
 378 /* This function must be called with interrupts turned off. */
 379 static void
 380 setup_rx_reqs(struct printer_dev *dev)
 381 {
 382         struct usb_request              *req;
 383
 384         while (likely(!list_empty(&dev->rx_reqs))) {
 385                 int error;
 386
 387                 req = container_of(dev->rx_reqs.next,
 388                                 struct usb_request, list);
 389                 list_del_init(&req->list);
 390
 391                 /* The USB Host sends us whatever amount of data it wants to
 392                  * so we always set the length field to the full USB_BUFSIZE.
 393                  * If the amount of data is more than the read() caller asked
 394                  * for it will be stored in the request buffer until it is
 395                  * asked for by read().
 396                  */
 397                 req->length = USB_BUFSIZE;
 398                 req->complete = rx_complete;
 399
 400                 /* here, we unlock, and only unlock, to avoid deadlock. */
 401                 spin_unlock(&dev->lock);
 402                 error = usb_ep_queue(dev->out_ep, req, GFP_ATOMIC);
 403                 spin_lock(&dev->lock);
 404                 if (error) {
 405                         DBG(dev, "rx submit --> %d\n", error);
 406                         list_add(&req->list, &dev->rx_reqs);
 407                         break;
 408                 }
 409                 /* if the req is empty, then add it into dev->rx_reqs_active. */
 410                 else if (list_empty(&req->list))
 411                         list_add(&req->list, &dev->rx_reqs_active);
 412         }
 413 }
 414
 415 static ssize_t
 416 printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr)
 417 {
 418         struct printer_dev              *dev = fd->private_data;
 419         unsigned long                   flags;
 420         size_t                          size;
 421         size_t                          bytes_copied;
 422         struct usb_request              *req;
 423         /* This is a pointer to the current USB rx request. */
 424         struct usb_request              *current_rx_req;
 425         /* This is the number of bytes in the current rx buffer. */
 426         size_t                          current_rx_bytes;
 427         /* This is a pointer to the current rx buffer. */
 428         u8                              *current_rx_buf;
 429
 430         if (len == 0)
 431                 return -EINVAL;
 432
 433         DBG(dev, "printer_read trying to read %d bytes\n", (int)len);
 434
 435         mutex_lock(&dev->lock_printer_io);
 436         spin_lock_irqsave(&dev->lock, flags);
 437
 438         /* We will use this flag later to check if a printer reset happened
 439          * after we turn interrupts back on.
 440          */
 441         dev->reset_printer = 0;
 442
 443         setup_rx_reqs(dev);
 444
 445         bytes_copied = 0;
 446         current_rx_req = dev->current_rx_req;
 447         current_rx_bytes = dev->current_rx_bytes;
 448         current_rx_buf = dev->current_rx_buf;
 449         dev->current_rx_req = NULL;
 450         dev->current_rx_bytes = 0;
 451         dev->current_rx_buf = NULL;
 452
 453         /* Check if there is any data in the read buffers. Please note that
 454          * current_rx_bytes is the number of bytes in the current rx buffer.
 455          * If it is zero then check if there are any other rx_buffers that
 456          * are on the completed list. We are only out of data if all rx
 457          * buffers are empty.
 458          */
 459         if ((current_rx_bytes == 0) &&
 460                         (likely(list_empty(&dev->rx_buffers)))) {
 461                 /* Turn interrupts back on before sleeping. */
 462                 spin_unlock_irqrestore(&dev->lock, flags);
 463
 464                 /*
 465                  * If no data is available check if this is a NON-Blocking
 466                  * call or not.
 467                  */
 468                 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
 469                         mutex_unlock(&dev->lock_printer_io);
 470                         return -EAGAIN;
 471                 }
 472
 473                 /* Sleep until data is available */
 474                 wait_event_interruptible(dev->rx_wait,
 475                                 (likely(!list_empty(&dev->rx_buffers))));
 476                 spin_lock_irqsave(&dev->lock, flags);
 477         }
 478
 479         /* We have data to return then copy it to the caller's buffer.*/
 480         while ((current_rx_bytes || likely(!list_empty(&dev->rx_buffers)))
 481                         && len) {
 482                 if (current_rx_bytes == 0) {
 483                         req = container_of(dev->rx_buffers.next,
 484                                         struct usb_request, list);
 485                         list_del_init(&req->list);
 486
 487                         if (req->actual && req->buf) {
 488                                 current_rx_req = req;
 489                                 current_rx_bytes = req->actual;
 490                                 current_rx_buf = req->buf;
 491                         } else {
 492                                 list_add(&req->list, &dev->rx_reqs);
 493                                 continue;
 494                         }
 495                 }
 496
 497                 /* Don't leave irqs off while doing memory copies */
 498                 spin_unlock_irqrestore(&dev->lock, flags);
 499
 500                 if (len > current_rx_bytes)
 501                         size = current_rx_bytes;
 502                 else
 503                         size = len;
 504
 505                 size -= copy_to_user(buf, current_rx_buf, size);
 506                 bytes_copied += size;
 507                 len -= size;
 508                 buf += size;
 509
 510                 spin_lock_irqsave(&dev->lock, flags);
 511
 512                 /* We've disconnected or reset so return. */
 513                 if (dev->reset_printer) {
 514                         list_add(&current_rx_req->list, &dev->rx_reqs);
 515                         spin_unlock_irqrestore(&dev->lock, flags);
 516                         mutex_unlock(&dev->lock_printer_io);
 517                         return -EAGAIN;
 518                 }
 519
 520                 /* If we not returning all the data left in this RX request
 521                  * buffer then adjust the amount of data left in the buffer.
 522                  * Othewise if we are done with this RX request buffer then
 523                  * requeue it to get any incoming data from the USB host.
 524                  */
 525                 if (size < current_rx_bytes) {
 526                         current_rx_bytes -= size;
 527                         current_rx_buf += size;
 528                 } else {
 529                         list_add(&current_rx_req->list, &dev->rx_reqs);
 530                         current_rx_bytes = 0;
 531                         current_rx_buf = NULL;
 532                         current_rx_req = NULL;
 533                 }
 534         }
 535
 536         dev->current_rx_req = current_rx_req;
 537         dev->current_rx_bytes = current_rx_bytes;
 538         dev->current_rx_buf = current_rx_buf;
 539
 540         spin_unlock_irqrestore(&dev->lock, flags);
 541         mutex_unlock(&dev->lock_printer_io);
 542
 543         DBG(dev, "printer_read returned %d bytes\n", (int)bytes_copied);
 544
 545         if (bytes_copied)
 546                 return bytes_copied;
 547         else
 548                 return -EAGAIN;
 549 }
 550
 551 static ssize_t
 552 printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
 553 {
 554         struct printer_dev      *dev = fd->private_data;
 555         unsigned long           flags;
 556         size_t                  size;   /* Amount of data in a TX request. */
 557         size_t                  bytes_copied = 0;
 558         struct usb_request      *req;
 559
 560         DBG(dev, "printer_write trying to send %d bytes\n", (int)len);
 561
 562         if (len == 0)
 563                 return -EINVAL;
 564
 565         mutex_lock(&dev->lock_printer_io);
 566         spin_lock_irqsave(&dev->lock, flags);
 567
 568         /* Check if a printer reset happens while we have interrupts on */
 569         dev->reset_printer = 0;
 570
 571         /* Check if there is any available write buffers */
 572         if (likely(list_empty(&dev->tx_reqs))) {
 573                 /* Turn interrupts back on before sleeping. */
 574                 spin_unlock_irqrestore(&dev->lock, flags);
 575
 576                 /*
 577                  * If write buffers are available check if this is
 578                  * a NON-Blocking call or not.
 579                  */
 580                 if (fd->f_flags & (O_NONBLOCK|O_NDELAY)) {
 581                         mutex_unlock(&dev->lock_printer_io);
 582                         return -EAGAIN;
 583                 }
 584
 585                 /* Sleep until a write buffer is available */
 586                 wait_event_interruptible(dev->tx_wait,
 587                                 (likely(!list_empty(&dev->tx_reqs))));
 588                 spin_lock_irqsave(&dev->lock, flags);
 589         }
 590
 591         while (likely(!list_empty(&dev->tx_reqs)) && len) {
 592
 593                 if (len > USB_BUFSIZE)
 594                         size = USB_BUFSIZE;
 595                 else
 596                         size = len;
 597
 598                 req = container_of(dev->tx_reqs.next, struct usb_request,
 599                                 list);
 600                 list_del_init(&req->list);
 601
 602                 req->complete = tx_complete;
 603                 req->length = size;
 604
 605                 /* Check if we need to send a zero length packet. */
 606                 if (len > size)
 607                         /* They will be more TX requests so no yet. */
 608                         req->zero = 0;
 609                 else
 610                         /* If the data amount is not a multiple of the
 611                          * maxpacket size then send a zero length packet.
 612                          */
 613                         req->zero = ((len % dev->in_ep->maxpacket) == 0);
 614
 615                 /* Don't leave irqs off while doing memory copies */
 616                 spin_unlock_irqrestore(&dev->lock, flags);
 617
 618                 if (copy_from_user(req->buf, buf, size)) {
 619                         list_add(&req->list, &dev->tx_reqs);
 620                         mutex_unlock(&dev->lock_printer_io);
 621                         return bytes_copied;
 622                 }
 623
 624                 bytes_copied += size;
 625                 len -= size;
 626                 buf += size;
 627
 628                 spin_lock_irqsave(&dev->lock, flags);
 629
 630                 /* We've disconnected or reset so free the req and buffer */
 631                 if (dev->reset_printer) {
 632                         list_add(&req->list, &dev->tx_reqs);
 633                         spin_unlock_irqrestore(&dev->lock, flags);
 634                         mutex_unlock(&dev->lock_printer_io);
 635                         return -EAGAIN;
 636                 }
 637
 638                 if (usb_ep_queue(dev->in_ep, req, GFP_ATOMIC)) {
 639                         list_add(&req->list, &dev->tx_reqs);
 640                         spin_unlock_irqrestore(&dev->lock, flags);
 641                         mutex_unlock(&dev->lock_printer_io);
 642                         return -EAGAIN;
 643                 }
 644
 645                 list_add(&req->list, &dev->tx_reqs_active);
 646
 647         }
 648
 649         spin_unlock_irqrestore(&dev->lock, flags);
 650         mutex_unlock(&dev->lock_printer_io);
 651
 652         DBG(dev, "printer_write sent %d bytes\n", (int)bytes_copied);
 653
 654         if (bytes_copied)
 655                 return bytes_copied;
 656         else
 657                 return -EAGAIN;
 658 }
 659
 660 static int
 661 printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync)
 662 {
 663         struct printer_dev      *dev = fd->private_data;
 664         struct inode *inode = file_inode(fd);
 665         unsigned long           flags;
 666         int                     tx_list_empty;
 667
 668         inode_lock(inode);
 669         spin_lock_irqsave(&dev->lock, flags);
 670         tx_list_empty = (likely(list_empty(&dev->tx_reqs)));
 671         spin_unlock_irqrestore(&dev->lock, flags);
 672
 673         if (!tx_list_empty) {
 674                 /* Sleep until all data has been sent */
 675                 wait_event_interruptible(dev->tx_flush_wait,
 676                                 (likely(list_empty(&dev->tx_reqs_active))));
 677         }
 678         inode_unlock(inode);
 679
 680         return 0;
 681 }
 682
 683 static unsigned int
 684 printer_poll(struct file *fd, poll_table *wait)
 685 {
 686         struct printer_dev      *dev = fd->private_data;
 687         unsigned long           flags;
 688         int                     status = 0;
 689
 690         mutex_lock(&dev->lock_printer_io);
 691         spin_lock_irqsave(&dev->lock, flags);
 692         setup_rx_reqs(dev);
 693         spin_unlock_irqrestore(&dev->lock, flags);
 694         mutex_unlock(&dev->lock_printer_io);
 695
 696         poll_wait(fd, &dev->rx_wait, wait);
 697         poll_wait(fd, &dev->tx_wait, wait);
 698
 699         spin_lock_irqsave(&dev->lock, flags);
 700         if (likely(!list_empty(&dev->tx_reqs)))
 701                 status |= POLLOUT | POLLWRNORM;
 702
 703         if (likely(dev->current_rx_bytes) ||
 704                         likely(!list_empty(&dev->rx_buffers)))
 705                 status |= POLLIN | POLLRDNORM;
 706
 707         spin_unlock_irqrestore(&dev->lock, flags);
 708
 709         return status;
 710 }
 711
 712 static long
 713 printer_ioctl(struct file *fd, unsigned int code, unsigned long arg)
 714 {
 715         struct printer_dev      *dev = fd->private_data;
 716         unsigned long           flags;
 717         int                     status = 0;
 718
 719         DBG(dev, "printer_ioctl: cmd=0x%4.4x, arg=%lu\n", code, arg);
 720
 721         /* handle ioctls */
 722
 723         spin_lock_irqsave(&dev->lock, flags);
 724
 725         switch (code) {
 726         case GADGET_GET_PRINTER_STATUS:
 727                 status = (int)dev->printer_status;
 728                 break;
 729         case GADGET_SET_PRINTER_STATUS:
 730                 dev->printer_status = (u8)arg;
 731                 break;
 732         default:
 733                 /* could not handle ioctl */
 734                 DBG(dev, "printer_ioctl: ERROR cmd=0x%4.4xis not supported\n",
 735                                 code);
 736                 status = -ENOTTY;
 737         }
 738
 739         spin_unlock_irqrestore(&dev->lock, flags);
 740
 741         return status;
 742 }
 743
 744 /* used after endpoint configuration */
 745 static const struct file_operations printer_io_operations = {
 746         .owner =        THIS_MODULE,
 747         .open =         printer_open,
 748         .read =         printer_read,
 749         .write =        printer_write,
 750         .fsync =        printer_fsync,
 751         .poll =         printer_poll,
 752         .unlocked_ioctl = printer_ioctl,
 753         .release =      printer_close,
 754         .llseek =       noop_llseek,
 755 };
 756
 757 /*-------------------------------------------------------------------------*/
 758
 759 static int
 760 set_printer_interface(struct printer_dev *dev)
 761 {
 762         int                     result = 0;
 763
 764         dev->in_ep->desc = ep_desc(dev->gadget, &fs_ep_in_desc, &hs_ep_in_desc,
 765                                 &ss_ep_in_desc);
 766         dev->in_ep->driver_data = dev;
 767
 768         dev->out_ep->desc = ep_desc(dev->gadget, &fs_ep_out_desc,
 769                                     &hs_ep_out_desc, &ss_ep_out_desc);
 770         dev->out_ep->driver_data = dev;
 771
 772         result = usb_ep_enable(dev->in_ep);
 773         if (result != 0) {
 774                 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
 775                 goto done;
 776         }
 777
 778         result = usb_ep_enable(dev->out_ep);
 779         if (result != 0) {
 780                 DBG(dev, "enable %s --> %d\n", dev->in_ep->name, result);
 781                 goto done;
 782         }
 783
 784 done:
 785         /* on error, disable any endpoints  */
 786         if (result != 0) {
 787                 (void) usb_ep_disable(dev->in_ep);
 788                 (void) usb_ep_disable(dev->out_ep);
 789                 dev->in_ep->desc = NULL;
 790                 dev->out_ep->desc = NULL;
 791         }
 792
 793         /* caller is responsible for cleanup on error */
 794         return result;
 795 }
 796
 797 static void printer_reset_interface(struct printer_dev *dev)
 798 {
 799         unsigned long   flags;
 800
 801         if (dev->interface < 0)
 802                 return;
 803
 804         DBG(dev, "%s\n", __func__);
 805
 806         if (dev->in_ep->desc)
 807                 usb_ep_disable(dev->in_ep);
 808
 809         if (dev->out_ep->desc)
 810                 usb_ep_disable(dev->out_ep);
 811
 812         spin_lock_irqsave(&dev->lock, flags);
 813         dev->in_ep->desc = NULL;
 814         dev->out_ep->desc = NULL;
 815         dev->interface = -1;
 816         spin_unlock_irqrestore(&dev->lock, flags);
 817 }
 818
 819 /* Change our operational Interface. */
 820 static int set_interface(struct printer_dev *dev, unsigned number)
 821 {
 822         int                     result = 0;
 823
 824         /* Free the current interface */
 825         printer_reset_interface(dev);
 826
 827         result = set_printer_interface(dev);
 828         if (result)
 829                 printer_reset_interface(dev);
 830         else
 831                 dev->interface = number;
 832
 833         if (!result)
 834                 INFO(dev, "Using interface %x\n", number);
 835
 836         return result;
 837 }
 838
 839 static void printer_soft_reset(struct printer_dev *dev)
 840 {
 841         struct usb_request      *req;
 842
 843         INFO(dev, "Received Printer Reset Request\n");
 844
 845         if (usb_ep_disable(dev->in_ep))
 846                 DBG(dev, "Failed to disable USB in_ep\n");
 847         if (usb_ep_disable(dev->out_ep))
 848                 DBG(dev, "Failed to disable USB out_ep\n");
 849
 850         if (dev->current_rx_req != NULL) {
 851                 list_add(&dev->current_rx_req->list, &dev->rx_reqs);
 852                 dev->current_rx_req = NULL;
 853         }
 854         dev->current_rx_bytes = 0;
 855         dev->current_rx_buf = NULL;
 856         dev->reset_printer = 1;
 857
 858         while (likely(!(list_empty(&dev->rx_buffers)))) {
 859                 req = container_of(dev->rx_buffers.next, struct usb_request,
 860                                 list);
 861                 list_del_init(&req->list);
 862                 list_add(&req->list, &dev->rx_reqs);
 863         }
 864
 865         while (likely(!(list_empty(&dev->rx_reqs_active)))) {
 866                 req = container_of(dev->rx_buffers.next, struct usb_request,
 867                                 list);
 868                 list_del_init(&req->list);
 869                 list_add(&req->list, &dev->rx_reqs);
 870         }
 871
 872         while (likely(!(list_empty(&dev->tx_reqs_active)))) {
 873                 req = container_of(dev->tx_reqs_active.next,
 874                                 struct usb_request, list);
 875                 list_del_init(&req->list);
 876                 list_add(&req->list, &dev->tx_reqs);
 877         }
 878
 879         if (usb_ep_enable(dev->in_ep))
 880                 DBG(dev, "Failed to enable USB in_ep\n");
 881         if (usb_ep_enable(dev->out_ep))
 882                 DBG(dev, "Failed to enable USB out_ep\n");
 883
 884         wake_up_interruptible(&dev->rx_wait);
 885         wake_up_interruptible(&dev->tx_wait);
 886         wake_up_interruptible(&dev->tx_flush_wait);
 887 }
 888
 889 /*-------------------------------------------------------------------------*/
 890
 891 static bool gprinter_req_match(struct usb_function *f,
 892                                const struct usb_ctrlrequest *ctrl)
 893 {
 894         struct printer_dev      *dev = func_to_printer(f);
 895         u16                     w_index = le16_to_cpu(ctrl->wIndex);
 896         u16                     w_value = le16_to_cpu(ctrl->wValue);
 897         u16                     w_length = le16_to_cpu(ctrl->wLength);
 898
 899         if ((ctrl->bRequestType & USB_RECIP_MASK) != USB_RECIP_INTERFACE ||
 900             (ctrl->bRequestType & USB_TYPE_MASK) != USB_TYPE_CLASS)
 901                 return false;
 902
 903         switch (ctrl->bRequest) {
 904         case GET_DEVICE_ID:
 905                 w_index >>= 8;
 906                 if (w_length <= PNP_STRING_LEN &&
 907                     (USB_DIR_IN & ctrl->bRequestType))
 908                         break;
 909                 return false;
 910         case GET_PORT_STATUS:
 911                 if (!w_value && w_length == 1 &&
 912                     (USB_DIR_IN & ctrl->bRequestType))
 913                         break;
 914                 return false;
 915         case SOFT_RESET:
 916                 if (!w_value && !w_length &&
 917                    !(USB_DIR_IN & ctrl->bRequestType))
 918                         break;
 919                 /* fall through */
 920         default:
 921                 return false;
 922         }
 923         return w_index == dev->interface;
 924 }
 925
 926 /*
 927  * The setup() callback implements all the ep0 functionality that's not
 928  * handled lower down.
 929  */
 930 static int printer_func_setup(struct usb_function *f,
 931                 const struct usb_ctrlrequest *ctrl)
 932 {
 933         struct printer_dev *dev = func_to_printer(f);
 934         struct usb_composite_dev *cdev = f->config->cdev;
 935         struct usb_request      *req = cdev->req;
 936         int                     value = -EOPNOTSUPP;
 937         u16                     wIndex = le16_to_cpu(ctrl->wIndex);
 938         u16                     wValue = le16_to_cpu(ctrl->wValue);
 939         u16                     wLength = le16_to_cpu(ctrl->wLength);
 940
 941         DBG(dev, "ctrl req%02x.%02x v%04x i%04x l%d\n",
 942                 ctrl->bRequestType, ctrl->bRequest, wValue, wIndex, wLength);
 943
 944         switch (ctrl->bRequestType&USB_TYPE_MASK) {
 945         case USB_TYPE_CLASS:
 946                 switch (ctrl->bRequest) {
 947                 case GET_DEVICE_ID: /* Get the IEEE-1284 PNP String */
 948                         /* Only one printer interface is supported. */
 949                         if ((wIndex>>8) != dev->interface)
 950                                 break;
 951
 952                         value = (dev->pnp_string[0] << 8) | dev->pnp_string[1];
 953                         memcpy(req->buf, dev->pnp_string, value);
 954                         DBG(dev, "1284 PNP String: %x %s\n", value,
 955                                         &dev->pnp_string[2]);
 956                         break;
 957
 958                 case GET_PORT_STATUS: /* Get Port Status */
 959                         /* Only one printer interface is supported. */
 960                         if (wIndex != dev->interface)
 961                                 break;
 962
 963                         *(u8 *)req->buf = dev->printer_status;
 964                         value = min_t(u16, wLength, 1);
 965                         break;
 966
 967                 case SOFT_RESET: /* Soft Reset */
 968                         /* Only one printer interface is supported. */
 969                         if (wIndex != dev->interface)
 970                                 break;
 971
 972                         printer_soft_reset(dev);
 973
 974                         value = 0;
 975                         break;
 976
 977                 default:
 978                         goto unknown;
 979                 }
 980                 break;
 981
 982         default:
 983 unknown:
 984                 VDBG(dev,
 985                         "unknown ctrl req%02x.%02x v%04x i%04x l%d\n",
 986                         ctrl->bRequestType, ctrl->bRequest,
 987                         wValue, wIndex, wLength);
 988                 break;
 989         }
 990         /* host either stalls (value < 0) or reports success */
 991         if (value >= 0) {
 992                 req->length = value;
 993                 req->zero = value < wLength;
 994                 value = usb_ep_queue(cdev->gadget->ep0, req, GFP_ATOMIC);
 995                 if (value < 0) {
 996                         ERROR(dev, "%s:%d Error!\n", __func__, __LINE__);
 997                         req->status = 0;
 998                 }
 999         }
1000         return value;
1001 }
1002
1003 static int printer_func_bind(struct usb_configuration *c,
1004                 struct usb_function *f)
1005 {
1006         struct usb_gadget *gadget = c->cdev->gadget;
1007         struct printer_dev *dev = func_to_printer(f);
1008         struct device *pdev;
1009         struct usb_composite_dev *cdev = c->cdev;
1010         struct usb_ep *in_ep;
1011         struct usb_ep *out_ep = NULL;
1012         struct usb_request *req;
1013         dev_t devt;
1014         int id;
1015         int ret;
1016         u32 i;
1017
1018         id = usb_interface_id(c, f);
1019         if (id < 0)
1020                 return id;
1021         intf_desc.bInterfaceNumber = id;
1022
1023         /* finish hookup to lower layer ... */
1024         dev->gadget = gadget;
1025
1026         /* all we really need is bulk IN/OUT */
1027         in_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_in_desc);
1028         if (!in_ep) {
1029 autoconf_fail:
1030                 dev_err(&cdev->gadget->dev, "can't autoconfigure on %s\n",
1031                         cdev->gadget->name);
1032                 return -ENODEV;
1033         }
1034
1035         out_ep = usb_ep_autoconfig(cdev->gadget, &fs_ep_out_desc);
1036         if (!out_ep)
1037                 goto autoconf_fail;
1038
1039         /* assumes that all endpoints are dual-speed */
1040         hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1041         hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1042         ss_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
1043         ss_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
1044
1045         ret = usb_assign_descriptors(f, fs_printer_function,
1046                         hs_printer_function, ss_printer_function, NULL);
1047         if (ret)
1048                 return ret;
1049
1050         dev->in_ep = in_ep;
1051         dev->out_ep = out_ep;
1052
1053         ret = -ENOMEM;
1054         for (i = 0; i < dev->q_len; i++) {
1055                 req = printer_req_alloc(dev->in_ep, USB_BUFSIZE, GFP_KERNEL);
1056                 if (!req)
1057                         goto fail_tx_reqs;
1058                 list_add(&req->list, &dev->tx_reqs);
1059         }
1060
1061         for (i = 0; i < dev->q_len; i++) {
1062                 req = printer_req_alloc(dev->out_ep, USB_BUFSIZE, GFP_KERNEL);
1063                 if (!req)
1064                         goto fail_rx_reqs;
1065                 list_add(&req->list, &dev->rx_reqs);
1066         }
1067
1068         /* Setup the sysfs files for the printer gadget. */
1069         devt = MKDEV(major, dev->minor);
1070         pdev = device_create(usb_gadget_class, NULL, devt,
1071                                   NULL, "g_printer%d", dev->minor);
1072         if (IS_ERR(pdev)) {
1073                 ERROR(dev, "Failed to create device: g_printer\n");
1074                 ret = PTR_ERR(pdev);
1075                 goto fail_rx_reqs;
1076         }
1077
1078         /*
1079          * Register a character device as an interface to a user mode
1080          * program that handles the printer specific functionality.
1081          */
1082         cdev_init(&dev->printer_cdev, &printer_io_operations);
1083         dev->printer_cdev.owner = THIS_MODULE;
1084         ret = cdev_add(&dev->printer_cdev, devt, 1);
1085         if (ret) {
1086                 ERROR(dev, "Failed to open char device\n");
1087                 goto fail_cdev_add;
1088         }
1089
1090         return 0;
1091
1092 fail_cdev_add:
1093         device_destroy(usb_gadget_class, devt);
1094
1095 fail_rx_reqs:
1096         while (!list_empty(&dev->rx_reqs)) {
1097                 req = container_of(dev->rx_reqs.next, struct usb_request, list);
1098                 list_del(&req->list);
1099                 printer_req_free(dev->out_ep, req);
1100         }
1101
1102 fail_tx_reqs:
1103         while (!list_empty(&dev->tx_reqs)) {
1104                 req = container_of(dev->tx_reqs.next, struct usb_request, list);
1105                 list_del(&req->list);
1106                 printer_req_free(dev->in_ep, req);
1107         }
1108
1109         return ret;
1110
1111 }
1112
1113 static int printer_func_set_alt(struct usb_function *f,
1114                 unsigned intf, unsigned alt)
1115 {
1116         struct printer_dev *dev = func_to_printer(f);
1117         int ret = -ENOTSUPP;
1118
1119         if (!alt)
1120                 ret = set_interface(dev, intf);
1121
1122         return ret;
1123 }
1124
1125 static void printer_func_disable(struct usb_function *f)
1126 {
1127         struct printer_dev *dev = func_to_printer(f);
1128
1129         DBG(dev, "%s\n", __func__);
1130
1131         printer_reset_interface(dev);
1132 }
1133
1134 static inline struct f_printer_opts
1135 *to_f_printer_opts(struct config_item *item)
1136 {
1137         return container_of(to_config_group(item), struct f_printer_opts,
1138                             func_inst.group);
1139 }
1140
1141 static void printer_attr_release(struct config_item *item)
1142 {
1143         struct f_printer_opts *opts = to_f_printer_opts(item);
1144
1145         usb_put_function_instance(&opts->func_inst);
1146 }
1147
1148 static struct configfs_item_operations printer_item_ops = {
1149         .release        = printer_attr_release,
1150 };
1151
1152 static ssize_t f_printer_opts_pnp_string_show(struct config_item *item,
1153                                               char *page)
1154 {
1155         struct f_printer_opts *opts = to_f_printer_opts(item);
1156         int result;
1157
1158         mutex_lock(&opts->lock);
1159         result = strlcpy(page, opts->pnp_string + 2, PNP_STRING_LEN - 2);
1160         mutex_unlock(&opts->lock);
1161
1162         return result;
1163 }
1164
1165 static ssize_t f_printer_opts_pnp_string_store(struct config_item *item,
1166                                                const char *page, size_t len)
1167 {
1168         struct f_printer_opts *opts = to_f_printer_opts(item);
1169         int result, l;
1170
1171         mutex_lock(&opts->lock);
1172         result = strlcpy(opts->pnp_string + 2, page, PNP_STRING_LEN - 2);
1173         l = strlen(opts->pnp_string + 2) + 2;
1174         opts->pnp_string[0] = (l >> 8) & 0xFF;
1175         opts->pnp_string[1] = l & 0xFF;
1176         mutex_unlock(&opts->lock);
1177
1178         return result;
1179 }
1180
1181 CONFIGFS_ATTR(f_printer_opts_, pnp_string);
1182
1183 static ssize_t f_printer_opts_q_len_show(struct config_item *item,
1184                                          char *page)
1185 {
1186         struct f_printer_opts *opts = to_f_printer_opts(item);
1187         int result;
1188
1189         mutex_lock(&opts->lock);
1190         result = sprintf(page, "%d\n", opts->q_len);
1191         mutex_unlock(&opts->lock);
1192
1193         return result;
1194 }
1195
1196 static ssize_t f_printer_opts_q_len_store(struct config_item *item,
1197                                           const char *page, size_t len)
1198 {
1199         struct f_printer_opts *opts = to_f_printer_opts(item);
1200         int ret;
1201         u16 num;
1202
1203         mutex_lock(&opts->lock);
1204         if (opts->refcnt) {
1205                 ret = -EBUSY;
1206                 goto end;
1207         }
1208
1209         ret = kstrtou16(page, 0, &num);
1210         if (ret)
1211                 goto end;
1212
1213         opts->q_len = (unsigned)num;
1214         ret = len;
1215 end:
1216         mutex_unlock(&opts->lock);
1217         return ret;
1218 }
1219
1220 CONFIGFS_ATTR(f_printer_opts_, q_len);
1221
1222 static struct configfs_attribute *printer_attrs[] = {
1223         &f_printer_opts_attr_pnp_string,
1224         &f_printer_opts_attr_q_len,
1225         NULL,
1226 };
1227
1228 static struct config_item_type printer_func_type = {
1229         .ct_item_ops    = &printer_item_ops,
1230         .ct_attrs       = printer_attrs,
1231         .ct_owner       = THIS_MODULE,
1232 };
1233
1234 static inline int gprinter_get_minor(void)
1235 {
1236         int ret;
1237
1238         ret = ida_simple_get(&printer_ida, 0, 0, GFP_KERNEL);
1239         if (ret >= PRINTER_MINORS) {
1240                 ida_simple_remove(&printer_ida, ret);
1241                 ret = -ENODEV;
1242         }
1243
1244         return ret;
1245 }
1246
1247 static inline void gprinter_put_minor(int minor)
1248 {
1249         ida_simple_remove(&printer_ida, minor);
1250 }
1251
1252 static int gprinter_setup(int);
1253 static void gprinter_cleanup(void);
1254
1255 static void gprinter_free_inst(struct usb_function_instance *f)
1256 {
1257         struct f_printer_opts *opts;
1258
1259         opts = container_of(f, struct f_printer_opts, func_inst);
1260
1261         mutex_lock(&printer_ida_lock);
1262
1263         gprinter_put_minor(opts->minor);
1264         if (idr_is_empty(&printer_ida.idr))
1265                 gprinter_cleanup();
1266
1267         mutex_unlock(&printer_ida_lock);
1268
1269         kfree(opts);
1270 }
1271
1272 static struct usb_function_instance *gprinter_alloc_inst(void)
1273 {
1274         struct f_printer_opts *opts;
1275         struct usb_function_instance *ret;
1276         int status = 0;
1277
1278         opts = kzalloc(sizeof(*opts), GFP_KERNEL);
1279         if (!opts)
1280                 return ERR_PTR(-ENOMEM);
1281
1282         mutex_init(&opts->lock);
1283         opts->func_inst.free_func_inst = gprinter_free_inst;
1284         ret = &opts->func_inst;
1285
1286         mutex_lock(&printer_ida_lock);
1287
1288         if (idr_is_empty(&printer_ida.idr)) {
1289                 status = gprinter_setup(PRINTER_MINORS);
1290                 if (status) {
1291                         ret = ERR_PTR(status);
1292                         kfree(opts);
1293                         goto unlock;
1294                 }
1295         }
1296
1297         opts->minor = gprinter_get_minor();
1298         if (opts->minor < 0) {
1299                 ret = ERR_PTR(opts->minor);
1300                 kfree(opts);
1301                 if (idr_is_empty(&printer_ida.idr))
1302                         gprinter_cleanup();
1303                 goto unlock;
1304         }
1305         config_group_init_type_name(&opts->func_inst.group, "",
1306                                     &printer_func_type);
1307
1308 unlock:
1309         mutex_unlock(&printer_ida_lock);
1310         return ret;
1311 }
1312
1313 static void gprinter_free(struct usb_function *f)
1314 {
1315         struct printer_dev *dev = func_to_printer(f);
1316         struct f_printer_opts *opts;
1317
1318         opts = container_of(f->fi, struct f_printer_opts, func_inst);
1319         kfree(dev);
1320         mutex_lock(&opts->lock);
1321         --opts->refcnt;
1322         mutex_unlock(&opts->lock);
1323 }
1324
1325 static void printer_func_unbind(struct usb_configuration *c,
1326                 struct usb_function *f)
1327 {
1328         struct printer_dev      *dev;
1329         struct usb_request      *req;
1330
1331         dev = func_to_printer(f);
1332
1333         device_destroy(usb_gadget_class, MKDEV(major, dev->minor));
1334
1335         /* Remove Character Device */
1336         cdev_del(&dev->printer_cdev);
1337
1338         /* we must already have been disconnected ... no i/o may be active */
1339         WARN_ON(!list_empty(&dev->tx_reqs_active));
1340         WARN_ON(!list_empty(&dev->rx_reqs_active));
1341
1342         /* Free all memory for this driver. */
1343         while (!list_empty(&dev->tx_reqs)) {
1344                 req = container_of(dev->tx_reqs.next, struct usb_request,
1345                                 list);
1346                 list_del(&req->list);
1347                 printer_req_free(dev->in_ep, req);
1348         }
1349
1350         if (dev->current_rx_req != NULL)
1351                 printer_req_free(dev->out_ep, dev->current_rx_req);
1352
1353         while (!list_empty(&dev->rx_reqs)) {
1354                 req = container_of(dev->rx_reqs.next,
1355                                 struct usb_request, list);
1356                 list_del(&req->list);
1357                 printer_req_free(dev->out_ep, req);
1358         }
1359
1360         while (!list_empty(&dev->rx_buffers)) {
1361                 req = container_of(dev->rx_buffers.next,
1362                                 struct usb_request, list);
1363                 list_del(&req->list);
1364                 printer_req_free(dev->out_ep, req);
1365         }
1366         usb_free_all_descriptors(f);
1367 }
1368
1369 static struct usb_function *gprinter_alloc(struct usb_function_instance *fi)
1370 {
1371         struct printer_dev      *dev;
1372         struct f_printer_opts   *opts;
1373
1374         opts = container_of(fi, struct f_printer_opts, func_inst);
1375
1376         mutex_lock(&opts->lock);
1377         if (opts->minor >= minors) {
1378                 mutex_unlock(&opts->lock);
1379                 return ERR_PTR(-ENOENT);
1380         }
1381
1382         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1383         if (!dev) {
1384                 mutex_unlock(&opts->lock);
1385                 return ERR_PTR(-ENOMEM);
1386         }
1387
1388         ++opts->refcnt;
1389         dev->minor = opts->minor;
1390         dev->pnp_string = opts->pnp_string;
1391         dev->q_len = opts->q_len;
1392         mutex_unlock(&opts->lock);
1393
1394         dev->function.name = "printer";
1395         dev->function.bind = printer_func_bind;
1396         dev->function.setup = printer_func_setup;
1397         dev->function.unbind = printer_func_unbind;
1398         dev->function.set_alt = printer_func_set_alt;
1399         dev->function.disable = printer_func_disable;
1400         dev->function.req_match = gprinter_req_match;
1401         dev->function.free_func = gprinter_free;
1402
1403         INIT_LIST_HEAD(&dev->tx_reqs);
1404         INIT_LIST_HEAD(&dev->rx_reqs);
1405         INIT_LIST_HEAD(&dev->rx_buffers);
1406         INIT_LIST_HEAD(&dev->tx_reqs_active);
1407         INIT_LIST_HEAD(&dev->rx_reqs_active);
1408
1409         spin_lock_init(&dev->lock);
1410         mutex_init(&dev->lock_printer_io);
1411         init_waitqueue_head(&dev->rx_wait);
1412         init_waitqueue_head(&dev->tx_wait);
1413         init_waitqueue_head(&dev->tx_flush_wait);
1414
1415         dev->interface = -1;
1416         dev->printer_cdev_open = 0;
1417         dev->printer_status = PRINTER_NOT_ERROR;
1418         dev->current_rx_req = NULL;
1419         dev->current_rx_bytes = 0;
1420         dev->current_rx_buf = NULL;
1421
1422         return &dev->function;
1423 }
1424
1425 DECLARE_USB_FUNCTION_INIT(printer, gprinter_alloc_inst, gprinter_alloc);
1426 MODULE_LICENSE("GPL");
1427 MODULE_AUTHOR("Craig Nadler");
1428
1429 static int gprinter_setup(int count)
1430 {
1431         int status;
1432         dev_t devt;
1433
1434         usb_gadget_class = class_create(THIS_MODULE, "usb_printer_gadget");
1435         if (IS_ERR(usb_gadget_class)) {
1436                 status = PTR_ERR(usb_gadget_class);
1437                 usb_gadget_class = NULL;
1438                 pr_err("unable to create usb_gadget class %d\n", status);
1439                 return status;
1440         }
1441
1442         status = alloc_chrdev_region(&devt, 0, count, "USB printer gadget");
1443         if (status) {
1444                 pr_err("alloc_chrdev_region %d\n", status);
1445                 class_destroy(usb_gadget_class);
1446                 usb_gadget_class = NULL;
1447                 return status;
1448         }
1449
1450         major = MAJOR(devt);
1451         minors = count;
1452
1453         return status;
1454 }
1455
1456 static void gprinter_cleanup(void)
1457 {
1458         if (major) {
1459                 unregister_chrdev_region(MKDEV(major, 0), minors);
1460                 major = minors = 0;
1461         }
1462         class_destroy(usb_gadget_class);
1463         usb_gadget_class = NULL;
1464 }