drivers/usb/gadget/f_mtp.c

   1 /*
   2  * Gadget Function Driver for MTP
   3  *
   4  * Copyright (C) 2010 Google, Inc.
   5  * Author: Mike Lockwood <lockwood@android.com>
   6  *
   7  * This software is licensed under the terms of the GNU General Public
   8  * License version 2, as published by the Free Software Foundation, and
   9  * may be copied, distributed, and modified under those terms.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17
  18 /* #define DEBUG */
  19 /* #define VERBOSE_DEBUG */
  20
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/poll.h>
  24 #include <linux/delay.h>
  25 #include <linux/wait.h>
  26 #include <linux/err.h>
  27 #include <linux/interrupt.h>
  28
  29 #include <linux/types.h>
  30 #include <linux/file.h>
  31 #include <linux/device.h>
  32 #include <linux/miscdevice.h>
  33
  34 #include <linux/usb.h>
  35 #include <linux/usb_usual.h>
  36 #include <linux/usb/ch9.h>
  37 #include <linux/usb/f_mtp.h>
  38
  39 #define MTP_BULK_BUFFER_SIZE       16384
  40 #define INTR_BUFFER_SIZE           28
  41
  42 /* String IDs */
  43 #define INTERFACE_STRING_INDEX  0
  44
  45 /* values for mtp_dev.state */
  46 #define STATE_OFFLINE               0   /* initial state, disconnected */
  47 #define STATE_READY                 1   /* ready for userspace calls */
  48 #define STATE_BUSY                  2   /* processing userspace calls */
  49 #define STATE_CANCELED              3   /* transaction canceled by host */
  50 #define STATE_ERROR                 4   /* error from completion routine */
  51
  52 /* number of tx and rx requests to allocate */
  53 #define TX_REQ_MAX 4
  54 #define RX_REQ_MAX 2
  55 #define INTR_REQ_MAX 5
  56
  57 /* ID for Microsoft MTP OS String */
  58 #define MTP_OS_STRING_ID   0xEE
  59
  60 /* MTP class reqeusts */
  61 #define MTP_REQ_CANCEL              0x64
  62 #define MTP_REQ_GET_EXT_EVENT_DATA  0x65
  63 #define MTP_REQ_RESET               0x66
  64 #define MTP_REQ_GET_DEVICE_STATUS   0x67
  65
  66 /* constants for device status */
  67 #define MTP_RESPONSE_OK             0x2001
  68 #define MTP_RESPONSE_DEVICE_BUSY    0x2019
  69
  70 static const char mtp_shortname[] = "mtp_usb";
  71
  72 struct mtp_dev {
  73         struct usb_function function;
  74         struct usb_composite_dev *cdev;
  75         spinlock_t lock;
  76
  77         struct usb_ep *ep_in;
  78         struct usb_ep *ep_out;
  79         struct usb_ep *ep_intr;
  80
  81         int state;
  82
  83         /* synchronize access to our device file */
  84         atomic_t open_excl;
  85         /* to enforce only one ioctl at a time */
  86         atomic_t ioctl_excl;
  87
  88         struct list_head tx_idle;
  89         struct list_head intr_idle;
  90
  91         wait_queue_head_t read_wq;
  92         wait_queue_head_t write_wq;
  93         wait_queue_head_t intr_wq;
  94         struct usb_request *rx_req[RX_REQ_MAX];
  95         int rx_done;
  96
  97         /* for processing MTP_SEND_FILE, MTP_RECEIVE_FILE and
  98          * MTP_SEND_FILE_WITH_HEADER ioctls on a work queue
  99          */
 100         struct workqueue_struct *wq;
 101         struct work_struct send_file_work;
 102         struct work_struct receive_file_work;
 103         struct file *xfer_file;
 104         loff_t xfer_file_offset;
 105         int64_t xfer_file_length;
 106         unsigned xfer_send_header;
 107         uint16_t xfer_command;
 108         uint32_t xfer_transaction_id;
 109         int xfer_result;
 110 };
 111
 112 static struct usb_interface_descriptor mtp_interface_desc = {
 113         .bLength                = USB_DT_INTERFACE_SIZE,
 114         .bDescriptorType        = USB_DT_INTERFACE,
 115         .bInterfaceNumber       = 0,
 116         .bNumEndpoints          = 3,
 117         .bInterfaceClass        = USB_CLASS_VENDOR_SPEC,
 118         .bInterfaceSubClass     = USB_SUBCLASS_VENDOR_SPEC,
 119         .bInterfaceProtocol     = 0,
 120 };
 121
 122 static struct usb_interface_descriptor ptp_interface_desc = {
 123         .bLength                = USB_DT_INTERFACE_SIZE,
 124         .bDescriptorType        = USB_DT_INTERFACE,
 125         .bInterfaceNumber       = 0,
 126         .bNumEndpoints          = 3,
 127         .bInterfaceClass        = USB_CLASS_STILL_IMAGE,
 128         .bInterfaceSubClass     = 1,
 129         .bInterfaceProtocol     = 1,
 130 };
 131
 132 static struct usb_endpoint_descriptor mtp_highspeed_in_desc = {
 133         .bLength                = USB_DT_ENDPOINT_SIZE,
 134         .bDescriptorType        = USB_DT_ENDPOINT,
 135         .bEndpointAddress       = USB_DIR_IN,
 136         .bmAttributes           = USB_ENDPOINT_XFER_BULK,
 137         .wMaxPacketSize         = __constant_cpu_to_le16(512),
 138 };
 139
 140 static struct usb_endpoint_descriptor mtp_highspeed_out_desc = {
 141         .bLength                = USB_DT_ENDPOINT_SIZE,
 142         .bDescriptorType        = USB_DT_ENDPOINT,
 143         .bEndpointAddress       = USB_DIR_OUT,
 144         .bmAttributes           = USB_ENDPOINT_XFER_BULK,
 145         .wMaxPacketSize         = __constant_cpu_to_le16(512),
 146 };
 147
 148 static struct usb_endpoint_descriptor mtp_fullspeed_in_desc = {
 149         .bLength                = USB_DT_ENDPOINT_SIZE,
 150         .bDescriptorType        = USB_DT_ENDPOINT,
 151         .bEndpointAddress       = USB_DIR_IN,
 152         .bmAttributes           = USB_ENDPOINT_XFER_BULK,
 153 };
 154
 155 static struct usb_endpoint_descriptor mtp_fullspeed_out_desc = {
 156         .bLength                = USB_DT_ENDPOINT_SIZE,
 157         .bDescriptorType        = USB_DT_ENDPOINT,
 158         .bEndpointAddress       = USB_DIR_OUT,
 159         .bmAttributes           = USB_ENDPOINT_XFER_BULK,
 160 };
 161
 162 static struct usb_endpoint_descriptor mtp_intr_desc = {
 163         .bLength                = USB_DT_ENDPOINT_SIZE,
 164         .bDescriptorType        = USB_DT_ENDPOINT,
 165         .bEndpointAddress       = USB_DIR_IN,
 166         .bmAttributes           = USB_ENDPOINT_XFER_INT,
 167         .wMaxPacketSize         = __constant_cpu_to_le16(INTR_BUFFER_SIZE),
 168         .bInterval              = 6,
 169 };
 170
 171 static struct usb_descriptor_header *fs_mtp_descs[] = {
 172         (struct usb_descriptor_header *) &mtp_interface_desc,
 173         (struct usb_descriptor_header *) &mtp_fullspeed_in_desc,
 174         (struct usb_descriptor_header *) &mtp_fullspeed_out_desc,
 175         (struct usb_descriptor_header *) &mtp_intr_desc,
 176         NULL,
 177 };
 178
 179 static struct usb_descriptor_header *hs_mtp_descs[] = {
 180         (struct usb_descriptor_header *) &mtp_interface_desc,
 181         (struct usb_descriptor_header *) &mtp_highspeed_in_desc,
 182         (struct usb_descriptor_header *) &mtp_highspeed_out_desc,
 183         (struct usb_descriptor_header *) &mtp_intr_desc,
 184         NULL,
 185 };
 186
 187 static struct usb_descriptor_header *fs_ptp_descs[] = {
 188         (struct usb_descriptor_header *) &ptp_interface_desc,
 189         (struct usb_descriptor_header *) &mtp_fullspeed_in_desc,
 190         (struct usb_descriptor_header *) &mtp_fullspeed_out_desc,
 191         (struct usb_descriptor_header *) &mtp_intr_desc,
 192         NULL,
 193 };
 194
 195 static struct usb_descriptor_header *hs_ptp_descs[] = {
 196         (struct usb_descriptor_header *) &ptp_interface_desc,
 197         (struct usb_descriptor_header *) &mtp_highspeed_in_desc,
 198         (struct usb_descriptor_header *) &mtp_highspeed_out_desc,
 199         (struct usb_descriptor_header *) &mtp_intr_desc,
 200         NULL,
 201 };
 202
 203 static struct usb_string mtp_string_defs[] = {
 204         /* Naming interface "MTP" so libmtp will recognize us */
 205         [INTERFACE_STRING_INDEX].s      = "MTP",
 206         {  },   /* end of list */
 207 };
 208
 209 static struct usb_gadget_strings mtp_string_table = {
 210         .language               = 0x0409,       /* en-US */
 211         .strings                = mtp_string_defs,
 212 };
 213
 214 static struct usb_gadget_strings *mtp_strings[] = {
 215         &mtp_string_table,
 216         NULL,
 217 };
 218
 219 /* Microsoft MTP OS String */
 220 static u8 mtp_os_string[] = {
 221         18, /* sizeof(mtp_os_string) */
 222         USB_DT_STRING,
 223         /* Signature field: "MSFT100" */
 224         'M', 0, 'S', 0, 'F', 0, 'T', 0, '1', 0, '0', 0, '0', 0,
 225         /* vendor code */
 226         1,
 227         /* padding */
 228         0
 229 };
 230
 231 /* Microsoft Extended Configuration Descriptor Header Section */
 232 struct mtp_ext_config_desc_header {
 233         __le32  dwLength;
 234         __u16   bcdVersion;
 235         __le16  wIndex;
 236         __u8    bCount;
 237         __u8    reserved[7];
 238 };
 239
 240 /* Microsoft Extended Configuration Descriptor Function Section */
 241 struct mtp_ext_config_desc_function {
 242         __u8    bFirstInterfaceNumber;
 243         __u8    bInterfaceCount;
 244         __u8    compatibleID[8];
 245         __u8    subCompatibleID[8];
 246         __u8    reserved[6];
 247 };
 248
 249 /* MTP Extended Configuration Descriptor */
 250 struct {
 251         struct mtp_ext_config_desc_header       header;
 252         struct mtp_ext_config_desc_function    function;
 253 } mtp_ext_config_desc = {
 254         .header = {
 255                 .dwLength = __constant_cpu_to_le32(sizeof(mtp_ext_config_desc)),
 256                 .bcdVersion = __constant_cpu_to_le16(0x0100),
 257                 .wIndex = __constant_cpu_to_le16(4),
 258                 .bCount = __constant_cpu_to_le16(1),
 259         },
 260         .function = {
 261                 .bFirstInterfaceNumber = 0,
 262                 .bInterfaceCount = 1,
 263                 .compatibleID = { 'M', 'T', 'P' },
 264         },
 265 };
 266
 267 struct mtp_device_status {
 268         __le16  wLength;
 269         __le16  wCode;
 270 };
 271
 272 /* temporary variable used between mtp_open() and mtp_gadget_bind() */
 273 static struct mtp_dev *_mtp_dev;
 274
 275 static inline struct mtp_dev *func_to_mtp(struct usb_function *f)
 276 {
 277         return container_of(f, struct mtp_dev, function);
 278 }
 279
 280 static struct usb_request *mtp_request_new(struct usb_ep *ep, int buffer_size)
 281 {
 282         struct usb_request *req = usb_ep_alloc_request(ep, GFP_KERNEL);
 283         if (!req)
 284                 return NULL;
 285
 286         /* now allocate buffers for the requests */
 287         req->buf = kmalloc(buffer_size, GFP_KERNEL);
 288         if (!req->buf) {
 289                 usb_ep_free_request(ep, req);
 290                 return NULL;
 291         }
 292
 293         return req;
 294 }
 295
 296 static void mtp_request_free(struct usb_request *req, struct usb_ep *ep)
 297 {
 298         if (req) {
 299                 kfree(req->buf);
 300                 usb_ep_free_request(ep, req);
 301         }
 302 }
 303
 304 static inline int mtp_lock(atomic_t *excl)
 305 {
 306         if (atomic_inc_return(excl) == 1) {
 307                 return 0;
 308         } else {
 309                 atomic_dec(excl);
 310                 return -1;
 311         }
 312 }
 313
 314 static inline void mtp_unlock(atomic_t *excl)
 315 {
 316         atomic_dec(excl);
 317 }
 318
 319 /* add a request to the tail of a list */
 320 static void mtp_req_put(struct mtp_dev *dev, struct list_head *head,
 321                 struct usb_request *req)
 322 {
 323         unsigned long flags;
 324
 325         spin_lock_irqsave(&dev->lock, flags);
 326         list_add_tail(&req->list, head);
 327         spin_unlock_irqrestore(&dev->lock, flags);
 328 }
 329
 330 /* remove a request from the head of a list */
 331 static struct usb_request
 332 *mtp_req_get(struct mtp_dev *dev, struct list_head *head)
 333 {
 334         unsigned long flags;
 335         struct usb_request *req;
 336
 337         spin_lock_irqsave(&dev->lock, flags);
 338         if (list_empty(head)) {
 339                 req = 0;
 340         } else {
 341                 req = list_first_entry(head, struct usb_request, list);
 342                 list_del(&req->list);
 343         }
 344         spin_unlock_irqrestore(&dev->lock, flags);
 345         return req;
 346 }
 347
 348 static void mtp_complete_in(struct usb_ep *ep, struct usb_request *req)
 349 {
 350         struct mtp_dev *dev = _mtp_dev;
 351
 352         if (req->status != 0)
 353                 dev->state = STATE_ERROR;
 354
 355         mtp_req_put(dev, &dev->tx_idle, req);
 356
 357         wake_up(&dev->write_wq);
 358 }
 359
 360 static void mtp_complete_out(struct usb_ep *ep, struct usb_request *req)
 361 {
 362         struct mtp_dev *dev = _mtp_dev;
 363
 364         dev->rx_done = 1;
 365         if (req->status != 0)
 366                 dev->state = STATE_ERROR;
 367
 368         wake_up(&dev->read_wq);
 369 }
 370
 371 static void mtp_complete_intr(struct usb_ep *ep, struct usb_request *req)
 372 {
 373         struct mtp_dev *dev = _mtp_dev;
 374
 375         if (req->status != 0)
 376                 dev->state = STATE_ERROR;
 377
 378         mtp_req_put(dev, &dev->intr_idle, req);
 379
 380         wake_up(&dev->intr_wq);
 381 }
 382
 383 static int mtp_create_bulk_endpoints(struct mtp_dev *dev,
 384                                 struct usb_endpoint_descriptor *in_desc,
 385                                 struct usb_endpoint_descriptor *out_desc,
 386                                 struct usb_endpoint_descriptor *intr_desc)
 387 {
 388         struct usb_composite_dev *cdev = dev->cdev;
 389         struct usb_request *req;
 390         struct usb_ep *ep;
 391         int i;
 392
 393         DBG(cdev, "create_bulk_endpoints dev: %p\n", dev);
 394
 395         ep = usb_ep_autoconfig(cdev->gadget, in_desc);
 396         if (!ep) {
 397                 DBG(cdev, "usb_ep_autoconfig for ep_in failed\n");
 398                 return -ENODEV;
 399         }
 400         DBG(cdev, "usb_ep_autoconfig for ep_in got %s\n", ep->name);
 401         ep->driver_data = dev;          /* claim the endpoint */
 402         dev->ep_in = ep;
 403
 404         ep = usb_ep_autoconfig(cdev->gadget, out_desc);
 405         if (!ep) {
 406                 DBG(cdev, "usb_ep_autoconfig for ep_out failed\n");
 407                 return -ENODEV;
 408         }
 409         DBG(cdev, "usb_ep_autoconfig for mtp ep_out got %s\n", ep->name);
 410         ep->driver_data = dev;          /* claim the endpoint */
 411         dev->ep_out = ep;
 412
 413         ep = usb_ep_autoconfig(cdev->gadget, intr_desc);
 414         if (!ep) {
 415                 DBG(cdev, "usb_ep_autoconfig for ep_intr failed\n");
 416                 return -ENODEV;
 417         }
 418         DBG(cdev, "usb_ep_autoconfig for mtp ep_intr got %s\n", ep->name);
 419         ep->driver_data = dev;          /* claim the endpoint */
 420         dev->ep_intr = ep;
 421
 422         /* now allocate requests for our endpoints */
 423         for (i = 0; i < TX_REQ_MAX; i++) {
 424                 req = mtp_request_new(dev->ep_in, MTP_BULK_BUFFER_SIZE);
 425                 if (!req)
 426                         goto fail;
 427                 req->complete = mtp_complete_in;
 428                 mtp_req_put(dev, &dev->tx_idle, req);
 429         }
 430         for (i = 0; i < RX_REQ_MAX; i++) {
 431                 req = mtp_request_new(dev->ep_out, MTP_BULK_BUFFER_SIZE);
 432                 if (!req)
 433                         goto fail;
 434                 req->complete = mtp_complete_out;
 435                 dev->rx_req[i] = req;
 436         }
 437         for (i = 0; i < INTR_REQ_MAX; i++) {
 438                 req = mtp_request_new(dev->ep_intr, INTR_BUFFER_SIZE);
 439                 if (!req)
 440                         goto fail;
 441                 req->complete = mtp_complete_intr;
 442                 mtp_req_put(dev, &dev->intr_idle, req);
 443         }
 444
 445         return 0;
 446
 447 fail:
 448         printk(KERN_ERR "mtp_bind() could not allocate requests\n");
 449         return -1;
 450 }
 451
 452 static ssize_t mtp_read(struct file *fp, char __user *buf,
 453         size_t count, loff_t *pos)
 454 {
 455         struct mtp_dev *dev = fp->private_data;
 456         struct usb_composite_dev *cdev = dev->cdev;
 457         struct usb_request *req;
 458         int r = count, xfer;
 459         int ret = 0;
 460
 461         DBG(cdev, "mtp_read(%d)\n", count);
 462
 463         if (count > MTP_BULK_BUFFER_SIZE)
 464                 return -EINVAL;
 465
 466         /* we will block until we're online */
 467         DBG(cdev, "mtp_read: waiting for online state\n");
 468         ret = wait_event_interruptible(dev->read_wq,
 469                 dev->state != STATE_OFFLINE);
 470         if (ret < 0) {
 471                 r = ret;
 472                 goto done;
 473         }
 474         spin_lock_irq(&dev->lock);
 475         if (dev->state == STATE_CANCELED) {
 476                 /* report cancelation to userspace */
 477                 dev->state = STATE_READY;
 478                 spin_unlock_irq(&dev->lock);
 479                 return -ECANCELED;
 480         }
 481         dev->state = STATE_BUSY;
 482         spin_unlock_irq(&dev->lock);
 483
 484 requeue_req:
 485         /* queue a request */
 486         req = dev->rx_req[0];
 487         req->length = count;
 488         dev->rx_done = 0;
 489         ret = usb_ep_queue(dev->ep_out, req, GFP_KERNEL);
 490         if (ret < 0) {
 491                 r = -EIO;
 492                 goto done;
 493         } else {
 494                 DBG(cdev, "rx %p queue\n", req);
 495         }
 496
 497         /* wait for a request to complete */
 498         ret = wait_event_interruptible(dev->read_wq, dev->rx_done);
 499         if (ret < 0) {
 500                 r = ret;
 501                 usb_ep_dequeue(dev->ep_out, req);
 502                 goto done;
 503         }
 504         if (dev->state == STATE_BUSY) {
 505                 /* If we got a 0-len packet, throw it back and try again. */
 506                 if (req->actual == 0)
 507                         goto requeue_req;
 508
 509                 DBG(cdev, "rx %p %d\n", req, req->actual);
 510                 xfer = (req->actual < count) ? req->actual : count;
 511                 r = xfer;
 512                 if (copy_to_user(buf, req->buf, xfer))
 513                         r = -EFAULT;
 514         } else
 515                 r = -EIO;
 516
 517 done:
 518         spin_lock_irq(&dev->lock);
 519         if (dev->state == STATE_CANCELED)
 520                 r = -ECANCELED;
 521         else if (dev->state != STATE_OFFLINE)
 522                 dev->state = STATE_READY;
 523         spin_unlock_irq(&dev->lock);
 524
 525         DBG(cdev, "mtp_read returning %d\n", r);
 526         return r;
 527 }
 528
 529 static ssize_t mtp_write(struct file *fp, const char __user *buf,
 530         size_t count, loff_t *pos)
 531 {
 532         struct mtp_dev *dev = fp->private_data;
 533         struct usb_composite_dev *cdev = dev->cdev;
 534         struct usb_request *req = 0;
 535         int r = count, xfer;
 536         int sendZLP = 0;
 537         int ret;
 538
 539         DBG(cdev, "mtp_write(%d)\n", count);
 540
 541         spin_lock_irq(&dev->lock);
 542         if (dev->state == STATE_CANCELED) {
 543                 /* report cancelation to userspace */
 544                 dev->state = STATE_READY;
 545                 spin_unlock_irq(&dev->lock);
 546                 return -ECANCELED;
 547         }
 548         if (dev->state == STATE_OFFLINE) {
 549                 spin_unlock_irq(&dev->lock);
 550                 return -ENODEV;
 551         }
 552         dev->state = STATE_BUSY;
 553         spin_unlock_irq(&dev->lock);
 554
 555         /* we need to send a zero length packet to signal the end of transfer
 556          * if the transfer size is aligned to a packet boundary.
 557          */
 558         if ((count & (dev->ep_in->maxpacket - 1)) == 0)
 559                 sendZLP = 1;
 560
 561         while (count > 0 || sendZLP) {
 562                 /* so we exit after sending ZLP */
 563                 if (count == 0)
 564                         sendZLP = 0;
 565
 566                 if (dev->state != STATE_BUSY) {
 567                         DBG(cdev, "mtp_write dev->error\n");
 568                         r = -EIO;
 569                         break;
 570                 }
 571
 572                 /* get an idle tx request to use */
 573                 req = 0;
 574                 ret = wait_event_interruptible(dev->write_wq,
 575                         ((req = mtp_req_get(dev, &dev->tx_idle))
 576                                 || dev->state != STATE_BUSY));
 577                 if (!req) {
 578                         r = ret;
 579                         break;
 580                 }
 581
 582                 if (count > MTP_BULK_BUFFER_SIZE)
 583                         xfer = MTP_BULK_BUFFER_SIZE;
 584                 else
 585                         xfer = count;
 586                 if (xfer && copy_from_user(req->buf, buf, xfer)) {
 587                         r = -EFAULT;
 588                         break;
 589                 }
 590
 591                 req->length = xfer;
 592                 ret = usb_ep_queue(dev->ep_in, req, GFP_KERNEL);
 593                 if (ret < 0) {
 594                         DBG(cdev, "mtp_write: xfer error %d\n", ret);
 595                         r = -EIO;
 596                         break;
 597                 }
 598
 599                 buf += xfer;
 600                 count -= xfer;
 601
 602                 /* zero this so we don't try to free it on error exit */
 603                 req = 0;
 604         }
 605
 606         if (req)
 607                 mtp_req_put(dev, &dev->tx_idle, req);
 608
 609         spin_lock_irq(&dev->lock);
 610         if (dev->state == STATE_CANCELED)
 611                 r = -ECANCELED;
 612         else if (dev->state != STATE_OFFLINE)
 613                 dev->state = STATE_READY;
 614         spin_unlock_irq(&dev->lock);
 615
 616         DBG(cdev, "mtp_write returning %d\n", r);
 617         return r;
 618 }
 619
 620 /* read from a local file and write to USB */
 621 static void send_file_work(struct work_struct *data)
 622 {
 623         struct mtp_dev *dev = container_of(data, struct mtp_dev,
 624                                                 send_file_work);
 625         struct usb_composite_dev *cdev = dev->cdev;
 626         struct usb_request *req = 0;
 627         struct mtp_data_header *header;
 628         struct file *filp;
 629         loff_t offset;
 630         int64_t count;
 631         int xfer, ret, hdr_size;
 632         int r = 0;
 633         int sendZLP = 0;
 634
 635         /* read our parameters */
 636         smp_rmb();
 637         filp = dev->xfer_file;
 638         offset = dev->xfer_file_offset;
 639         count = dev->xfer_file_length;
 640
 641         DBG(cdev, "send_file_work(%lld %lld)\n", offset, count);
 642
 643         if (dev->xfer_send_header) {
 644                 hdr_size = sizeof(struct mtp_data_header);
 645                 count += hdr_size;
 646         } else {
 647                 hdr_size = 0;
 648         }
 649
 650         /* we need to send a zero length packet to signal the end of transfer
 651          * if the transfer size is aligned to a packet boundary.
 652          */
 653         if ((count & (dev->ep_in->maxpacket - 1)) == 0)
 654                 sendZLP = 1;
 655
 656         while (count > 0 || sendZLP) {
 657                 /* so we exit after sending ZLP */
 658                 if (count == 0)
 659                         sendZLP = 0;
 660
 661                 /* get an idle tx request to use */
 662                 req = 0;
 663                 ret = wait_event_interruptible(dev->write_wq,
 664                         (req = mtp_req_get(dev, &dev->tx_idle))
 665                         || dev->state != STATE_BUSY);
 666                 if (dev->state == STATE_CANCELED) {
 667                         r = -ECANCELED;
 668                         break;
 669                 }
 670                 if (!req) {
 671                         r = ret;
 672                         break;
 673                 }
 674
 675                 if (count > MTP_BULK_BUFFER_SIZE)
 676                         xfer = MTP_BULK_BUFFER_SIZE;
 677                 else
 678                         xfer = count;
 679
 680                 if (hdr_size) {
 681                         /* prepend MTP data header */
 682                         header = (struct mtp_data_header *)req->buf;
 683                         header->length = __cpu_to_le32(count);
 684                         header->type = __cpu_to_le16(2); /* data packet */
 685                         header->command = __cpu_to_le16(dev->xfer_command);
 686                         header->transaction_id =
 687                                         __cpu_to_le32(dev->xfer_transaction_id);
 688                 }
 689
 690                 ret = vfs_read(filp, req->buf + hdr_size, xfer - hdr_size,
 691                                                                 &offset);
 692                 if (ret < 0) {
 693                         r = ret;
 694                         break;
 695                 }
 696                 xfer = ret + hdr_size;
 697                 hdr_size = 0;
 698
 699                 req->length = xfer;
 700                 ret = usb_ep_queue(dev->ep_in, req, GFP_KERNEL);
 701                 if (ret < 0) {
 702                         DBG(cdev, "send_file_work: xfer error %d\n", ret);
 703                         dev->state = STATE_ERROR;
 704                         r = -EIO;
 705                         break;
 706                 }
 707
 708                 count -= xfer;
 709
 710                 /* zero this so we don't try to free it on error exit */
 711                 req = 0;
 712         }
 713
 714         if (req)
 715                 mtp_req_put(dev, &dev->tx_idle, req);
 716
 717         DBG(cdev, "send_file_work returning %d\n", r);
 718         /* write the result */
 719         dev->xfer_result = r;
 720         smp_wmb();
 721 }
 722
 723 /* read from USB and write to a local file */
 724 static void receive_file_work(struct work_struct *data)
 725 {
 726         struct mtp_dev *dev = container_of(data, struct mtp_dev,
 727                                                 receive_file_work);
 728         struct usb_composite_dev *cdev = dev->cdev;
 729         struct usb_request *read_req = NULL, *write_req = NULL;
 730         struct file *filp;
 731         loff_t offset;
 732         int64_t count;
 733         int ret, cur_buf = 0;
 734         int r = 0;
 735
 736         /* read our parameters */
 737         smp_rmb();
 738         filp = dev->xfer_file;
 739         offset = dev->xfer_file_offset;
 740         count = dev->xfer_file_length;
 741
 742         DBG(cdev, "receive_file_work(%lld)\n", count);
 743
 744         while (count > 0 || write_req) {
 745                 if (count > 0) {
 746                         /* queue a request */
 747                         read_req = dev->rx_req[cur_buf];
 748                         cur_buf = (cur_buf + 1) % RX_REQ_MAX;
 749
 750                         read_req->length = (count > MTP_BULK_BUFFER_SIZE
 751                                         ? MTP_BULK_BUFFER_SIZE : count);
 752                         dev->rx_done = 0;
 753                         ret = usb_ep_queue(dev->ep_out, read_req, GFP_KERNEL);
 754                         if (ret < 0) {
 755                                 r = -EIO;
 756                                 dev->state = STATE_ERROR;
 757                                 break;
 758                         }
 759                 }
 760
 761                 if (write_req) {
 762                         DBG(cdev, "rx %p %d\n", write_req, write_req->actual);
 763                         ret = vfs_write(filp, write_req->buf, write_req->actual,
 764                                 &offset);
 765                         DBG(cdev, "vfs_write %d\n", ret);
 766                         if (ret != write_req->actual) {
 767                                 r = -EIO;
 768                                 dev->state = STATE_ERROR;
 769                                 break;
 770                         }
 771                         write_req = NULL;
 772                 }
 773
 774                 if (read_req) {
 775                         /* wait for our last read to complete */
 776                         ret = wait_event_interruptible(dev->read_wq,
 777                                 dev->rx_done || dev->state != STATE_BUSY);
 778                         if (dev->state == STATE_CANCELED) {
 779                                 r = -ECANCELED;
 780                                 if (!dev->rx_done)
 781                                         usb_ep_dequeue(dev->ep_out, read_req);
 782                                 break;
 783                         }
 784                         /* if xfer_file_length is 0xFFFFFFFF, then we read until
 785                          * we get a zero length packet
 786                          */
 787                         if (count != 0xFFFFFFFF)
 788                                 count -= read_req->actual;
 789                         if (read_req->actual < read_req->length) {
 790                                 /*
 791                                  * short packet is used to signal EOF for
 792                                  * sizes > 4 gig
 793                                  */
 794                                 DBG(cdev, "got short packet\n");
 795                                 count = 0;
 796                         }
 797
 798                         write_req = read_req;
 799                         read_req = NULL;
 800                 }
 801         }
 802
 803         DBG(cdev, "receive_file_work returning %d\n", r);
 804         /* write the result */
 805         dev->xfer_result = r;
 806         smp_wmb();
 807 }
 808
 809 static int mtp_send_event(struct mtp_dev *dev, struct mtp_event *event)
 810 {
 811         struct usb_request *req = NULL;
 812         int ret;
 813         int length = event->length;
 814
 815         DBG(dev->cdev, "mtp_send_event(%d)\n", event->length);
 816
 817         if (length < 0 || length > INTR_BUFFER_SIZE)
 818                 return -EINVAL;
 819         if (dev->state == STATE_OFFLINE)
 820                 return -ENODEV;
 821
 822         ret = wait_event_interruptible_timeout(dev->intr_wq,
 823                         (req = mtp_req_get(dev, &dev->intr_idle)),
 824                         msecs_to_jiffies(1000));
 825         if (!req)
 826                 return -ETIME;
 827
 828         if (copy_from_user(req->buf, (void __user *)event->data, length)) {
 829                 mtp_req_put(dev, &dev->intr_idle, req);
 830                 return -EFAULT;
 831         }
 832         req->length = length;
 833         ret = usb_ep_queue(dev->ep_intr, req, GFP_KERNEL);
 834         if (ret)
 835                 mtp_req_put(dev, &dev->intr_idle, req);
 836
 837         return ret;
 838 }
 839
 840 static long mtp_ioctl(struct file *fp, unsigned code, unsigned long value)
 841 {
 842         struct mtp_dev *dev = fp->private_data;
 843         struct file *filp = NULL;
 844         int ret = -EINVAL;
 845
 846         if (mtp_lock(&dev->ioctl_excl))
 847                 return -EBUSY;
 848
 849         switch (code) {
 850         case MTP_SEND_FILE:
 851         case MTP_RECEIVE_FILE:
 852         case MTP_SEND_FILE_WITH_HEADER:
 853         {
 854                 struct mtp_file_range   mfr;
 855                 struct work_struct *work;
 856
 857                 spin_lock_irq(&dev->lock);
 858                 if (dev->state == STATE_CANCELED) {
 859                         /* report cancelation to userspace */
 860                         dev->state = STATE_READY;
 861                         spin_unlock_irq(&dev->lock);
 862                         ret = -ECANCELED;
 863                         goto out;
 864                 }
 865                 if (dev->state == STATE_OFFLINE) {
 866                         spin_unlock_irq(&dev->lock);
 867                         ret = -ENODEV;
 868                         goto out;
 869                 }
 870                 dev->state = STATE_BUSY;
 871                 spin_unlock_irq(&dev->lock);
 872
 873                 if (copy_from_user(&mfr, (void __user *)value, sizeof(mfr))) {
 874                         ret = -EFAULT;
 875                         goto fail;
 876                 }
 877                 /* hold a reference to the file while we are working with it */
 878                 filp = fget(mfr.fd);
 879                 if (!filp) {
 880                         ret = -EBADF;
 881                         goto fail;
 882                 }
 883
 884                 /* write the parameters */
 885                 dev->xfer_file = filp;
 886                 dev->xfer_file_offset = mfr.offset;
 887                 dev->xfer_file_length = mfr.length;
 888                 smp_wmb();
 889
 890                 if (code == MTP_SEND_FILE_WITH_HEADER) {
 891                         work = &dev->send_file_work;
 892                         dev->xfer_send_header = 1;
 893                         dev->xfer_command = mfr.command;
 894                         dev->xfer_transaction_id = mfr.transaction_id;
 895                 } else if (code == MTP_SEND_FILE) {
 896                         work = &dev->send_file_work;
 897                         dev->xfer_send_header = 0;
 898                 } else {
 899                         work = &dev->receive_file_work;
 900                 }
 901
 902                 /* We do the file transfer on a work queue so it will run
 903                  * in kernel context, which is necessary for vfs_read and
 904                  * vfs_write to use our buffers in the kernel address space.
 905                  */
 906                 queue_work(dev->wq, work);
 907                 /* wait for operation to complete */
 908                 flush_workqueue(dev->wq);
 909                 fput(filp);
 910
 911                 /* read the result */
 912                 smp_rmb();
 913                 ret = dev->xfer_result;
 914                 break;
 915         }
 916         case MTP_SEND_EVENT:
 917         {
 918                 struct mtp_event        event;
 919                 /* return here so we don't change dev->state below,
 920                  * which would interfere with bulk transfer state.
 921                  */
 922                 if (copy_from_user(&event, (void __user *)value, sizeof(event)))
 923                         ret = -EFAULT;
 924                 else
 925                         ret = mtp_send_event(dev, &event);
 926                 goto out;
 927         }
 928         }
 929
 930 fail:
 931         spin_lock_irq(&dev->lock);
 932         if (dev->state == STATE_CANCELED)
 933                 ret = -ECANCELED;
 934         else if (dev->state != STATE_OFFLINE)
 935                 dev->state = STATE_READY;
 936         spin_unlock_irq(&dev->lock);
 937 out:
 938         mtp_unlock(&dev->ioctl_excl);
 939         DBG(dev->cdev, "ioctl returning %d\n", ret);
 940         return ret;
 941 }
 942
 943 static int mtp_open(struct inode *ip, struct file *fp)
 944 {
 945         printk(KERN_INFO "mtp_open\n");
 946         if (mtp_lock(&_mtp_dev->open_excl))
 947                 return -EBUSY;
 948
 949         /* clear any error condition */
 950         if (_mtp_dev->state != STATE_OFFLINE)
 951                 _mtp_dev->state = STATE_READY;
 952
 953         fp->private_data = _mtp_dev;
 954         return 0;
 955 }
 956
 957 static int mtp_release(struct inode *ip, struct file *fp)
 958 {
 959         printk(KERN_INFO "mtp_release\n");
 960
 961         mtp_unlock(&_mtp_dev->open_excl);
 962         return 0;
 963 }
 964
 965 /* file operations for /dev/mtp_usb */
 966 static const struct file_operations mtp_fops = {
 967         .owner = THIS_MODULE,
 968         .read = mtp_read,
 969         .write = mtp_write,
 970         .unlocked_ioctl = mtp_ioctl,
 971         .open = mtp_open,
 972         .release = mtp_release,
 973 };
 974
 975 static struct miscdevice mtp_device = {
 976         .minor = MISC_DYNAMIC_MINOR,
 977         .name = mtp_shortname,
 978         .fops = &mtp_fops,
 979 };
 980
 981 static int mtp_ctrlrequest(struct usb_composite_dev *cdev,
 982                                 const struct usb_ctrlrequest *ctrl)
 983 {
 984         struct mtp_dev *dev = _mtp_dev;
 985         int     value = -EOPNOTSUPP;
 986         u16     w_index = le16_to_cpu(ctrl->wIndex);
 987         u16     w_value = le16_to_cpu(ctrl->wValue);
 988         u16     w_length = le16_to_cpu(ctrl->wLength);
 989         unsigned long   flags;
 990
 991         VDBG(cdev, "mtp_ctrlrequest "
 992                         "%02x.%02x v%04x i%04x l%u\n",
 993                         ctrl->bRequestType, ctrl->bRequest,
 994                         w_value, w_index, w_length);
 995
 996         /* Handle MTP OS string */
 997         if (ctrl->bRequestType ==
 998                         (USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE)
 999                         && ctrl->bRequest == USB_REQ_GET_DESCRIPTOR
1000                         && (w_value >> 8) == USB_DT_STRING
1001                         && (w_value & 0xFF) == MTP_OS_STRING_ID) {
1002                 value = (w_length < sizeof(mtp_os_string)
1003                                 ? w_length : sizeof(mtp_os_string));
1004                 memcpy(cdev->req->buf, mtp_os_string, value);
1005         } else if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_VENDOR) {
1006                 /* Handle MTP OS descriptor */
1007                 DBG(cdev, "vendor request: %d index: %d value: %d length: %d\n",
1008                         ctrl->bRequest, w_index, w_value, w_length);
1009
1010                 if (ctrl->bRequest == 1
1011                                 && (ctrl->bRequestType & USB_DIR_IN)
1012                                 && (w_index == 4 || w_index == 5)) {
1013                         value = (w_length < sizeof(mtp_ext_config_desc) ?
1014                                         w_length : sizeof(mtp_ext_config_desc));
1015                         memcpy(cdev->req->buf, &mtp_ext_config_desc, value);
1016                 }
1017         } else if ((ctrl->bRequestType & USB_TYPE_MASK) == USB_TYPE_CLASS) {
1018                 DBG(cdev, "class request: %d index: %d value: %d length: %d\n",
1019                         ctrl->bRequest, w_index, w_value, w_length);
1020
1021                 if (ctrl->bRequest == MTP_REQ_CANCEL && w_index == 0
1022                                 && w_value == 0) {
1023                         DBG(cdev, "MTP_REQ_CANCEL\n");
1024
1025                         spin_lock_irqsave(&dev->lock, flags);
1026                         if (dev->state == STATE_BUSY) {
1027                                 dev->state = STATE_CANCELED;
1028                                 wake_up(&dev->read_wq);
1029                                 wake_up(&dev->write_wq);
1030                         }
1031                         spin_unlock_irqrestore(&dev->lock, flags);
1032
1033                         /* We need to queue a request to read the remaining
1034                          *  bytes, but we don't actually need to look at
1035                          * the contents.
1036                          */
1037                         value = w_length;
1038                 } else if (ctrl->bRequest == MTP_REQ_GET_DEVICE_STATUS
1039                                 && w_index == 0 && w_value == 0) {
1040                         struct mtp_device_status *status = cdev->req->buf;
1041                         status->wLength =
1042                                 __constant_cpu_to_le16(sizeof(*status));
1043
1044                         DBG(cdev, "MTP_REQ_GET_DEVICE_STATUS\n");
1045                         spin_lock_irqsave(&dev->lock, flags);
1046                         /* device status is "busy" until we report
1047                          * the cancelation to userspace
1048                          */
1049                         if (dev->state == STATE_CANCELED)
1050                                 status->wCode =
1051                                         __cpu_to_le16(MTP_RESPONSE_DEVICE_BUSY);
1052                         else
1053                                 status->wCode =
1054                                         __cpu_to_le16(MTP_RESPONSE_OK);
1055                         spin_unlock_irqrestore(&dev->lock, flags);
1056                         value = sizeof(*status);
1057                 }
1058         }
1059
1060         /* respond with data transfer or status phase? */
1061         if (value >= 0) {
1062                 int rc;
1063                 cdev->req->zero = value < w_length;
1064                 cdev->req->length = value;
1065                 rc = usb_ep_queue(cdev->gadget->ep0, cdev->req, GFP_ATOMIC);
1066                 if (rc < 0)
1067                         ERROR(cdev, "%s: response queue error\n", __func__);
1068         }
1069         return value;
1070 }
1071
1072 static int
1073 mtp_function_bind(struct usb_configuration *c, struct usb_function *f)
1074 {
1075         struct usb_composite_dev *cdev = c->cdev;
1076         struct mtp_dev  *dev = func_to_mtp(f);
1077         int                     id;
1078         int                     ret;
1079
1080         dev->cdev = cdev;
1081         DBG(cdev, "mtp_function_bind dev: %p\n", dev);
1082
1083         /* allocate interface ID(s) */
1084         id = usb_interface_id(c, f);
1085         if (id < 0)
1086                 return id;
1087         mtp_interface_desc.bInterfaceNumber = id;
1088
1089         /* allocate endpoints */
1090         ret = mtp_create_bulk_endpoints(dev, &mtp_fullspeed_in_desc,
1091                         &mtp_fullspeed_out_desc, &mtp_intr_desc);
1092         if (ret)
1093                 return ret;
1094
1095         /* support high speed hardware */
1096         if (gadget_is_dualspeed(c->cdev->gadget)) {
1097                 mtp_highspeed_in_desc.bEndpointAddress =
1098                         mtp_fullspeed_in_desc.bEndpointAddress;
1099                 mtp_highspeed_out_desc.bEndpointAddress =
1100                         mtp_fullspeed_out_desc.bEndpointAddress;
1101         }
1102
1103         DBG(cdev, "%s speed %s: IN/%s, OUT/%s\n",
1104                         gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
1105                         f->name, dev->ep_in->name, dev->ep_out->name);
1106         return 0;
1107 }
1108
1109 static void
1110 mtp_function_unbind(struct usb_configuration *c, struct usb_function *f)
1111 {
1112         struct mtp_dev  *dev = func_to_mtp(f);
1113         struct usb_request *req;
1114         int i;
1115
1116         while ((req = mtp_req_get(dev, &dev->tx_idle)))
1117                 mtp_request_free(req, dev->ep_in);
1118         for (i = 0; i < RX_REQ_MAX; i++)
1119                 mtp_request_free(dev->rx_req[i], dev->ep_out);
1120         while ((req = mtp_req_get(dev, &dev->intr_idle)))
1121                 mtp_request_free(req, dev->ep_intr);
1122         dev->state = STATE_OFFLINE;
1123 }
1124
1125 static int mtp_function_set_alt(struct usb_function *f,
1126                 unsigned intf, unsigned alt)
1127 {
1128         struct mtp_dev  *dev = func_to_mtp(f);
1129         struct usb_composite_dev *cdev = f->config->cdev;
1130         int ret;
1131
1132         DBG(cdev, "mtp_function_set_alt intf: %d alt: %d\n", intf, alt);
1133
1134         ret = config_ep_by_speed(cdev->gadget, f, dev->ep_in);
1135         if (ret)
1136                 return ret;
1137
1138         ret = usb_ep_enable(dev->ep_in);
1139         if (ret)
1140                 return ret;
1141
1142         ret = config_ep_by_speed(cdev->gadget, f, dev->ep_out);
1143         if (ret)
1144                 return ret;
1145
1146         ret = usb_ep_enable(dev->ep_out);
1147         if (ret) {
1148                 usb_ep_disable(dev->ep_in);
1149                 return ret;
1150         }
1151
1152         ret = config_ep_by_speed(cdev->gadget, f, dev->ep_intr);
1153         if (ret)
1154                 return ret;
1155
1156         ret = usb_ep_enable(dev->ep_intr);
1157         if (ret) {
1158                 usb_ep_disable(dev->ep_out);
1159                 usb_ep_disable(dev->ep_in);
1160                 return ret;
1161         }
1162         dev->state = STATE_READY;
1163
1164         /* readers may be blocked waiting for us to go online */
1165         wake_up(&dev->read_wq);
1166         return 0;
1167 }
1168
1169 static void mtp_function_disable(struct usb_function *f)
1170 {
1171         struct mtp_dev  *dev = func_to_mtp(f);
1172         struct usb_composite_dev        *cdev = dev->cdev;
1173
1174         DBG(cdev, "mtp_function_disable\n");
1175         dev->state = STATE_OFFLINE;
1176         usb_ep_disable(dev->ep_in);
1177         usb_ep_disable(dev->ep_out);
1178         usb_ep_disable(dev->ep_intr);
1179
1180         /* readers may be blocked waiting for us to go online */
1181         wake_up(&dev->read_wq);
1182
1183         VDBG(cdev, "%s disabled\n", dev->function.name);
1184 }
1185
1186 static int mtp_bind_config(struct usb_configuration *c, bool ptp_config)
1187 {
1188         struct mtp_dev *dev = _mtp_dev;
1189         int ret = 0;
1190
1191         printk(KERN_INFO "mtp_bind_config\n");
1192
1193         /* allocate a string ID for our interface */
1194         if (mtp_string_defs[INTERFACE_STRING_INDEX].id == 0) {
1195                 ret = usb_string_id(c->cdev);
1196                 if (ret < 0)
1197                         return ret;
1198                 mtp_string_defs[INTERFACE_STRING_INDEX].id = ret;
1199                 mtp_interface_desc.iInterface = ret;
1200         }
1201
1202         dev->cdev = c->cdev;
1203         dev->function.name = "mtp";
1204         dev->function.strings = mtp_strings;
1205         if (ptp_config) {
1206                 dev->function.fs_descriptors = fs_ptp_descs;
1207                 dev->function.hs_descriptors = hs_ptp_descs;
1208         } else {
1209                 dev->function.fs_descriptors = fs_mtp_descs;
1210                 dev->function.hs_descriptors = hs_mtp_descs;
1211         }
1212         dev->function.bind = mtp_function_bind;
1213         dev->function.unbind = mtp_function_unbind;
1214         dev->function.set_alt = mtp_function_set_alt;
1215         dev->function.disable = mtp_function_disable;
1216
1217         return usb_add_function(c, &dev->function);
1218 }
1219
1220 static int mtp_setup(void)
1221 {
1222         struct mtp_dev *dev;
1223         int ret;
1224
1225         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1226         if (!dev)
1227                 return -ENOMEM;
1228
1229         spin_lock_init(&dev->lock);
1230         init_waitqueue_head(&dev->read_wq);
1231         init_waitqueue_head(&dev->write_wq);
1232         init_waitqueue_head(&dev->intr_wq);
1233         atomic_set(&dev->open_excl, 0);
1234         atomic_set(&dev->ioctl_excl, 0);
1235         INIT_LIST_HEAD(&dev->tx_idle);
1236         INIT_LIST_HEAD(&dev->intr_idle);
1237
1238         dev->wq = create_singlethread_workqueue("f_mtp");
1239         if (!dev->wq) {
1240                 ret = -ENOMEM;
1241                 goto err1;
1242         }
1243         INIT_WORK(&dev->send_file_work, send_file_work);
1244         INIT_WORK(&dev->receive_file_work, receive_file_work);
1245
1246         _mtp_dev = dev;
1247
1248         ret = misc_register(&mtp_device);
1249         if (ret)
1250                 goto err2;
1251
1252         return 0;
1253
1254 err2:
1255         destroy_workqueue(dev->wq);
1256 err1:
1257         _mtp_dev = NULL;
1258         kfree(dev);
1259         printk(KERN_ERR "mtp gadget driver failed to initialize\n");
1260         return ret;
1261 }
1262
1263 static void mtp_cleanup(void)
1264 {
1265         struct mtp_dev *dev = _mtp_dev;
1266
1267         if (!dev)
1268                 return;
1269
1270         misc_deregister(&mtp_device);
1271         destroy_workqueue(dev->wq);
1272         _mtp_dev = NULL;
1273         kfree(dev);
1274 }