1/* 2 * inode.c -- user mode filesystem api for usb gadget controllers 3 * 4 * Copyright (C) 2003-2004 David Brownell 5 * Copyright (C) 2003 Agilent Technologies 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 */ 12 13 14/* #define VERBOSE_DEBUG */ 15 16#include <linux/init.h> 17#include <linux/module.h> 18#include <linux/fs.h> 19#include <linux/pagemap.h> 20#include <linux/uts.h> 21#include <linux/wait.h> 22#include <linux/compiler.h> 23#include <asm/uaccess.h> 24#include <linux/sched.h> 25#include <linux/slab.h> 26#include <linux/poll.h> 27 28#include <linux/device.h> 29#include <linux/moduleparam.h> 30 31#include <linux/usb/gadgetfs.h> 32#include <linux/usb/gadget.h> 33 34 35/* 36 * The gadgetfs API maps each endpoint to a file descriptor so that you 37 * can use standard synchronous read/write calls for I/O. There's some 38 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode 39 * drivers show how this works in practice. You can also use AIO to 40 * eliminate I/O gaps between requests, to help when streaming data. 41 * 42 * Key parts that must be USB-specific are protocols defining how the 43 * read/write operations relate to the hardware state machines. There 44 * are two types of files. One type is for the device, implementing ep0. 45 * The other type is for each IN or OUT endpoint. In both cases, the 46 * user mode driver must configure the hardware before using it. 47 * 48 * - First, dev_config() is called when /dev/gadget/$CHIP is configured 49 * (by writing configuration and device descriptors). Afterwards it 50 * may serve as a source of device events, used to handle all control 51 * requests other than basic enumeration. 52 * 53 * - Then, after a SET_CONFIGURATION control request, ep_config() is 54 * called when each /dev/gadget/ep* file is configured (by writing 55 * endpoint descriptors). Afterwards these files are used to write() 56 * IN data or to read() OUT data. To halt the endpoint, a "wrong 57 * direction" request is issued (like reading an IN endpoint). 58 * 59 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe 60 * not possible on all hardware. For example, precise fault handling with 61 * respect to data left in endpoint fifos after aborted operations; or 62 * selective clearing of endpoint halts, to implement SET_INTERFACE. 63 */ 64 65#define DRIVER_DESC "USB Gadget filesystem" 66#define DRIVER_VERSION "24 Aug 2004" 67 68static const char driver_desc [] = DRIVER_DESC; 69static const char shortname [] = "gadgetfs"; 70 71MODULE_DESCRIPTION (DRIVER_DESC); 72MODULE_AUTHOR ("David Brownell"); 73MODULE_LICENSE ("GPL"); 74 75 76/*----------------------------------------------------------------------*/ 77 78#define GADGETFS_MAGIC 0xaee71ee7 79#define DMA_ADDR_INVALID (~(dma_addr_t)0) 80 81/* /dev/gadget/$CHIP represents ep0 and the whole device */ 82enum ep0_state { 83 /* DISBLED is the initial state. 84 */ 85 STATE_DEV_DISABLED = 0, 86 87 /* Only one open() of /dev/gadget/$CHIP; only one file tracks 88 * ep0/device i/o modes and binding to the controller. Driver 89 * must always write descriptors to initialize the device, then 90 * the device becomes UNCONNECTED until enumeration. 91 */ 92 STATE_DEV_OPENED, 93 94 /* From then on, ep0 fd is in either of two basic modes: 95 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it 96 * - SETUP: read/write will transfer control data and succeed; 97 * or if "wrong direction", performs protocol stall 98 */ 99 STATE_DEV_UNCONNECTED, 100 STATE_DEV_CONNECTED, 101 STATE_DEV_SETUP, 102 103 /* UNBOUND means the driver closed ep0, so the device won't be 104 * accessible again (DEV_DISABLED) until all fds are closed. 105 */ 106 STATE_DEV_UNBOUND, 107}; 108 109/* enough for the whole queue: most events invalidate others */ 110#define N_EVENT 5 111 112struct dev_data { 113 spinlock_t lock; 114 atomic_t count; 115 enum ep0_state state; /* P: lock */ 116 struct usb_gadgetfs_event event [N_EVENT]; 117 unsigned ev_next; 118 struct fasync_struct *fasync; 119 u8 current_config; 120 121 /* drivers reading ep0 MUST handle control requests (SETUP) 122 * reported that way; else the host will time out. 123 */ 124 unsigned usermode_setup : 1, 125 setup_in : 1, 126 setup_can_stall : 1, 127 setup_out_ready : 1, 128 setup_out_error : 1, 129 setup_abort : 1; 130 unsigned setup_wLength; 131 132 /* the rest is basically write-once */ 133 struct usb_config_descriptor *config, *hs_config; 134 struct usb_device_descriptor *dev; 135 struct usb_request *req; 136 struct usb_gadget *gadget; 137 struct list_head epfiles; 138 void *buf; 139 wait_queue_head_t wait; 140 struct super_block *sb; 141 struct dentry *dentry; 142 143 /* except this scratch i/o buffer for ep0 */ 144 u8 rbuf [256]; 145}; 146 147static inline void get_dev (struct dev_data *data) 148{ 149 atomic_inc (&data->count); 150} 151 152static void put_dev (struct dev_data *data) 153{ 154 if (likely (!atomic_dec_and_test (&data->count))) 155 return; 156 /* needs no more cleanup */ 157 BUG_ON (waitqueue_active (&data->wait)); 158 kfree (data); 159} 160 161static struct dev_data *dev_new (void) 162{ 163 struct dev_data *dev; 164 165 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 166 if (!dev) 167 return NULL; 168 dev->state = STATE_DEV_DISABLED; 169 atomic_set (&dev->count, 1); 170 spin_lock_init (&dev->lock); 171 INIT_LIST_HEAD (&dev->epfiles); 172 init_waitqueue_head (&dev->wait); 173 return dev; 174} 175 176/*----------------------------------------------------------------------*/ 177 178/* other /dev/gadget/$ENDPOINT files represent endpoints */ 179enum ep_state { 180 STATE_EP_DISABLED = 0, 181 STATE_EP_READY, 182 STATE_EP_ENABLED, 183 STATE_EP_UNBOUND, 184}; 185 186struct ep_data { 187 struct mutex lock; 188 enum ep_state state; 189 atomic_t count; 190 struct dev_data *dev; 191 /* must hold dev->lock before accessing ep or req */ 192 struct usb_ep *ep; 193 struct usb_request *req; 194 ssize_t status; 195 char name [16]; 196 struct usb_endpoint_descriptor desc, hs_desc; 197 struct list_head epfiles; 198 wait_queue_head_t wait; 199 struct dentry *dentry; 200 struct inode *inode; 201}; 202 203static inline void get_ep (struct ep_data *data) 204{ 205 atomic_inc (&data->count); 206} 207 208static void put_ep (struct ep_data *data) 209{ 210 if (likely (!atomic_dec_and_test (&data->count))) 211 return; 212 put_dev (data->dev); 213 /* needs no more cleanup */ 214 BUG_ON (!list_empty (&data->epfiles)); 215 BUG_ON (waitqueue_active (&data->wait)); 216 kfree (data); 217} 218 219/*----------------------------------------------------------------------*/ 220 221/* most "how to use the hardware" policy choices are in userspace: 222 * mapping endpoint roles (which the driver needs) to the capabilities 223 * which the usb controller has. most of those capabilities are exposed 224 * implicitly, starting with the driver name and then endpoint names. 225 */ 226 227static const char *CHIP; 228 229/*----------------------------------------------------------------------*/ 230 231/* NOTE: don't use dev_printk calls before binding to the gadget 232 * at the end of ep0 configuration, or after unbind. 233 */ 234 235/* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */ 236#define xprintk(d,level,fmt,args...) \ 237 printk(level "%s: " fmt , shortname , ## args) 238 239#ifdef DEBUG 240#define DBG(dev,fmt,args...) \ 241 xprintk(dev , KERN_DEBUG , fmt , ## args) 242#else 243#define DBG(dev,fmt,args...) \ 244 do { } while (0) 245#endif /* DEBUG */ 246 247#ifdef VERBOSE_DEBUG 248#define VDEBUG DBG 249#else 250#define VDEBUG(dev,fmt,args...) \ 251 do { } while (0) 252#endif /* DEBUG */ 253 254#define ERROR(dev,fmt,args...) \ 255 xprintk(dev , KERN_ERR , fmt , ## args) 256#define INFO(dev,fmt,args...) \ 257 xprintk(dev , KERN_INFO , fmt , ## args) 258 259 260/*----------------------------------------------------------------------*/ 261 262/* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso) 263 * 264 * After opening, configure non-control endpoints. Then use normal 265 * stream read() and write() requests; and maybe ioctl() to get more 266 * precise FIFO status when recovering from cancellation. 267 */ 268 269static void epio_complete (struct usb_ep *ep, struct usb_request *req) 270{ 271 struct ep_data *epdata = ep->driver_data; 272 273 if (!req->context) 274 return; 275 if (req->status) 276 epdata->status = req->status; 277 else 278 epdata->status = req->actual; 279 complete ((struct completion *)req->context); 280} 281 282/* tasklock endpoint, returning when it's connected. 283 * still need dev->lock to use epdata->ep. 284 */ 285static int 286get_ready_ep (unsigned f_flags, struct ep_data *epdata) 287{ 288 int val; 289 290 if (f_flags & O_NONBLOCK) { 291 if (!mutex_trylock(&epdata->lock)) 292 goto nonblock; 293 if (epdata->state != STATE_EP_ENABLED) { 294 mutex_unlock(&epdata->lock); 295nonblock: 296 val = -EAGAIN; 297 } else 298 val = 0; 299 return val; 300 } 301 302 val = mutex_lock_interruptible(&epdata->lock); 303 if (val < 0) 304 return val; 305 306 switch (epdata->state) { 307 case STATE_EP_ENABLED: 308 break; 309 // case STATE_EP_DISABLED: /* "can't happen" */ 310 // case STATE_EP_READY: /* "can't happen" */ 311 default: /* error! */ 312 pr_debug ("%s: ep %p not available, state %d\n", 313 shortname, epdata, epdata->state); 314 // FALLTHROUGH 315 case STATE_EP_UNBOUND: /* clean disconnect */ 316 val = -ENODEV; 317 mutex_unlock(&epdata->lock); 318 } 319 return val; 320} 321 322static ssize_t 323ep_io (struct ep_data *epdata, void *buf, unsigned len) 324{ 325 DECLARE_COMPLETION_ONSTACK (done); 326 int value; 327 328 spin_lock_irq (&epdata->dev->lock); 329 if (likely (epdata->ep != NULL)) { 330 struct usb_request *req = epdata->req; 331 332 req->context = &done; 333 req->complete = epio_complete; 334 req->buf = buf; 335 req->length = len; 336 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC); 337 } else 338 value = -ENODEV; 339 spin_unlock_irq (&epdata->dev->lock); 340 341 if (likely (value == 0)) { 342 value = wait_event_interruptible (done.wait, done.done); 343 if (value != 0) { 344 spin_lock_irq (&epdata->dev->lock); 345 if (likely (epdata->ep != NULL)) { 346 DBG (epdata->dev, "%s i/o interrupted\n", 347 epdata->name); 348 usb_ep_dequeue (epdata->ep, epdata->req); 349 spin_unlock_irq (&epdata->dev->lock); 350 351 wait_event (done.wait, done.done); 352 if (epdata->status == -ECONNRESET) 353 epdata->status = -EINTR; 354 } else { 355 spin_unlock_irq (&epdata->dev->lock); 356 357 DBG (epdata->dev, "endpoint gone\n"); 358 epdata->status = -ENODEV; 359 } 360 } 361 return epdata->status; 362 } 363 return value; 364} 365 366 367/* handle a synchronous OUT bulk/intr/iso transfer */ 368static ssize_t 369ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) 370{ 371 struct ep_data *data = fd->private_data; 372 void *kbuf; 373 ssize_t value; 374 375 if ((value = get_ready_ep (fd->f_flags, data)) < 0) 376 return value; 377 378 /* halt any endpoint by doing a "wrong direction" i/o call */ 379 if (usb_endpoint_dir_in(&data->desc)) { 380 if (usb_endpoint_xfer_isoc(&data->desc)) { 381 mutex_unlock(&data->lock); 382 return -EINVAL; 383 } 384 DBG (data->dev, "%s halt\n", data->name); 385 spin_lock_irq (&data->dev->lock); 386 if (likely (data->ep != NULL)) 387 usb_ep_set_halt (data->ep); 388 spin_unlock_irq (&data->dev->lock); 389 mutex_unlock(&data->lock); 390 return -EBADMSG; 391 } 392 393 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */ 394 395 value = -ENOMEM; 396 kbuf = kmalloc (len, GFP_KERNEL); 397 if (unlikely (!kbuf)) 398 goto free1; 399 400 value = ep_io (data, kbuf, len); 401 VDEBUG (data->dev, "%s read %zu OUT, status %d\n", 402 data->name, len, (int) value); 403 if (value >= 0 && copy_to_user (buf, kbuf, value)) 404 value = -EFAULT; 405 406free1: 407 mutex_unlock(&data->lock); 408 kfree (kbuf); 409 return value; 410} 411 412/* handle a synchronous IN bulk/intr/iso transfer */ 413static ssize_t 414ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 415{ 416 struct ep_data *data = fd->private_data; 417 void *kbuf; 418 ssize_t value; 419 420 if ((value = get_ready_ep (fd->f_flags, data)) < 0) 421 return value; 422 423 /* halt any endpoint by doing a "wrong direction" i/o call */ 424 if (!usb_endpoint_dir_in(&data->desc)) { 425 if (usb_endpoint_xfer_isoc(&data->desc)) { 426 mutex_unlock(&data->lock); 427 return -EINVAL; 428 } 429 DBG (data->dev, "%s halt\n", data->name); 430 spin_lock_irq (&data->dev->lock); 431 if (likely (data->ep != NULL)) 432 usb_ep_set_halt (data->ep); 433 spin_unlock_irq (&data->dev->lock); 434 mutex_unlock(&data->lock); 435 return -EBADMSG; 436 } 437 438 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */ 439 440 value = -ENOMEM; 441 kbuf = kmalloc (len, GFP_KERNEL); 442 if (!kbuf) 443 goto free1; 444 if (copy_from_user (kbuf, buf, len)) { 445 value = -EFAULT; 446 goto free1; 447 } 448 449 value = ep_io (data, kbuf, len); 450 VDEBUG (data->dev, "%s write %zu IN, status %d\n", 451 data->name, len, (int) value); 452free1: 453 mutex_unlock(&data->lock); 454 kfree (kbuf); 455 return value; 456} 457 458static int 459ep_release (struct inode *inode, struct file *fd) 460{ 461 struct ep_data *data = fd->private_data; 462 int value; 463 464 value = mutex_lock_interruptible(&data->lock); 465 if (value < 0) 466 return value; 467 468 /* clean up if this can be reopened */ 469 if (data->state != STATE_EP_UNBOUND) { 470 data->state = STATE_EP_DISABLED; 471 data->desc.bDescriptorType = 0; 472 data->hs_desc.bDescriptorType = 0; 473 usb_ep_disable(data->ep); 474 } 475 mutex_unlock(&data->lock); 476 put_ep (data); 477 return 0; 478} 479 480static long ep_ioctl(struct file *fd, unsigned code, unsigned long value) 481{ 482 struct ep_data *data = fd->private_data; 483 int status; 484 485 if ((status = get_ready_ep (fd->f_flags, data)) < 0) 486 return status; 487 488 spin_lock_irq (&data->dev->lock); 489 if (likely (data->ep != NULL)) { 490 switch (code) { 491 case GADGETFS_FIFO_STATUS: 492 status = usb_ep_fifo_status (data->ep); 493 break; 494 case GADGETFS_FIFO_FLUSH: 495 usb_ep_fifo_flush (data->ep); 496 break; 497 case GADGETFS_CLEAR_HALT: 498 status = usb_ep_clear_halt (data->ep); 499 break; 500 default: 501 status = -ENOTTY; 502 } 503 } else 504 status = -ENODEV; 505 spin_unlock_irq (&data->dev->lock); 506 mutex_unlock(&data->lock); 507 return status; 508} 509 510/*----------------------------------------------------------------------*/ 511 512/* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */ 513 514struct kiocb_priv { 515 struct usb_request *req; 516 struct ep_data *epdata; 517 void *buf; 518 const struct iovec *iv; 519 unsigned long nr_segs; 520 unsigned actual; 521}; 522 523static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e) 524{ 525 struct kiocb_priv *priv = iocb->private; 526 struct ep_data *epdata; 527 int value; 528 529 local_irq_disable(); 530 epdata = priv->epdata; 531 // spin_lock(&epdata->dev->lock); 532 kiocbSetCancelled(iocb); 533 if (likely(epdata && epdata->ep && priv->req)) 534 value = usb_ep_dequeue (epdata->ep, priv->req); 535 else 536 value = -EINVAL; 537 // spin_unlock(&epdata->dev->lock); 538 local_irq_enable(); 539 540 aio_put_req(iocb); 541 return value; 542} 543 544static ssize_t ep_aio_read_retry(struct kiocb *iocb) 545{ 546 struct kiocb_priv *priv = iocb->private; 547 ssize_t len, total; 548 void *to_copy; 549 int i; 550 551 /* we "retry" to get the right mm context for this: */ 552 553 /* copy stuff into user buffers */ 554 total = priv->actual; 555 len = 0; 556 to_copy = priv->buf; 557 for (i=0; i < priv->nr_segs; i++) { 558 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total); 559 560 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) { 561 if (len == 0) 562 len = -EFAULT; 563 break; 564 } 565 566 total -= this; 567 len += this; 568 to_copy += this; 569 if (total == 0) 570 break; 571 } 572 kfree(priv->buf); 573 kfree(priv); 574 return len; 575} 576 577static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req) 578{ 579 struct kiocb *iocb = req->context; 580 struct kiocb_priv *priv = iocb->private; 581 struct ep_data *epdata = priv->epdata; 582 583 /* lock against disconnect (and ideally, cancel) */ 584 spin_lock(&epdata->dev->lock); 585 priv->req = NULL; 586 priv->epdata = NULL; 587 588 /* if this was a write or a read returning no data then we 589 * don't need to copy anything to userspace, so we can 590 * complete the aio request immediately. 591 */ 592 if (priv->iv == NULL || unlikely(req->actual == 0)) { 593 kfree(req->buf); 594 kfree(priv); 595 iocb->private = NULL; 596 /* aio_complete() reports bytes-transferred _and_ faults */ 597 aio_complete(iocb, req->actual ? req->actual : req->status, 598 req->status); 599 } else { 600 /* retry() won't report both; so we hide some faults */ 601 if (unlikely(0 != req->status)) 602 DBG(epdata->dev, "%s fault %d len %d\n", 603 ep->name, req->status, req->actual); 604 605 priv->buf = req->buf; 606 priv->actual = req->actual; 607 kick_iocb(iocb); 608 } 609 spin_unlock(&epdata->dev->lock); 610 611 usb_ep_free_request(ep, req); 612 put_ep(epdata); 613} 614 615static ssize_t 616ep_aio_rwtail( 617 struct kiocb *iocb, 618 char *buf, 619 size_t len, 620 struct ep_data *epdata, 621 const struct iovec *iv, 622 unsigned long nr_segs 623) 624{ 625 struct kiocb_priv *priv; 626 struct usb_request *req; 627 ssize_t value; 628 629 priv = kmalloc(sizeof *priv, GFP_KERNEL); 630 if (!priv) { 631 value = -ENOMEM; 632fail: 633 kfree(buf); 634 return value; 635 } 636 iocb->private = priv; 637 priv->iv = iv; 638 priv->nr_segs = nr_segs; 639 640 value = get_ready_ep(iocb->ki_filp->f_flags, epdata); 641 if (unlikely(value < 0)) { 642 kfree(priv); 643 goto fail; 644 } 645 646 iocb->ki_cancel = ep_aio_cancel; 647 get_ep(epdata); 648 priv->epdata = epdata; 649 priv->actual = 0; 650 651 /* each kiocb is coupled to one usb_request, but we can't 652 * allocate or submit those if the host disconnected. 653 */ 654 spin_lock_irq(&epdata->dev->lock); 655 if (likely(epdata->ep)) { 656 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC); 657 if (likely(req)) { 658 priv->req = req; 659 req->buf = buf; 660 req->length = len; 661 req->complete = ep_aio_complete; 662 req->context = iocb; 663 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC); 664 if (unlikely(0 != value)) 665 usb_ep_free_request(epdata->ep, req); 666 } else 667 value = -EAGAIN; 668 } else 669 value = -ENODEV; 670 spin_unlock_irq(&epdata->dev->lock); 671 672 mutex_unlock(&epdata->lock); 673 674 if (unlikely(value)) { 675 kfree(priv); 676 put_ep(epdata); 677 } else 678 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED); 679 return value; 680} 681 682static ssize_t 683ep_aio_read(struct kiocb *iocb, const struct iovec *iov, 684 unsigned long nr_segs, loff_t o) 685{ 686 struct ep_data *epdata = iocb->ki_filp->private_data; 687 char *buf; 688 689 if (unlikely(usb_endpoint_dir_in(&epdata->desc))) 690 return -EINVAL; 691 692 buf = kmalloc(iocb->ki_left, GFP_KERNEL); 693 if (unlikely(!buf)) 694 return -ENOMEM; 695 696 iocb->ki_retry = ep_aio_read_retry; 697 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs); 698} 699 700static ssize_t 701ep_aio_write(struct kiocb *iocb, const struct iovec *iov, 702 unsigned long nr_segs, loff_t o) 703{ 704 struct ep_data *epdata = iocb->ki_filp->private_data; 705 char *buf; 706 size_t len = 0; 707 int i = 0; 708 709 if (unlikely(!usb_endpoint_dir_in(&epdata->desc))) 710 return -EINVAL; 711 712 buf = kmalloc(iocb->ki_left, GFP_KERNEL); 713 if (unlikely(!buf)) 714 return -ENOMEM; 715 716 for (i=0; i < nr_segs; i++) { 717 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base, 718 iov[i].iov_len) != 0)) { 719 kfree(buf); 720 return -EFAULT; 721 } 722 len += iov[i].iov_len; 723 } 724 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0); 725} 726 727/*----------------------------------------------------------------------*/ 728 729/* used after endpoint configuration */ 730static const struct file_operations ep_io_operations = { 731 .owner = THIS_MODULE, 732 .llseek = no_llseek, 733 734 .read = ep_read, 735 .write = ep_write, 736 .unlocked_ioctl = ep_ioctl, 737 .release = ep_release, 738 739 .aio_read = ep_aio_read, 740 .aio_write = ep_aio_write, 741}; 742 743/* ENDPOINT INITIALIZATION 744 * 745 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR) 746 * status = write (fd, descriptors, sizeof descriptors) 747 * 748 * That write establishes the endpoint configuration, configuring 749 * the controller to process bulk, interrupt, or isochronous transfers 750 * at the right maxpacket size, and so on. 751 * 752 * The descriptors are message type 1, identified by a host order u32 753 * at the beginning of what's written. Descriptor order is: full/low 754 * speed descriptor, then optional high speed descriptor. 755 */ 756static ssize_t 757ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 758{ 759 struct ep_data *data = fd->private_data; 760 struct usb_ep *ep; 761 u32 tag; 762 int value, length = len; 763 764 value = mutex_lock_interruptible(&data->lock); 765 if (value < 0) 766 return value; 767 768 if (data->state != STATE_EP_READY) { 769 value = -EL2HLT; 770 goto fail; 771 } 772 773 value = len; 774 if (len < USB_DT_ENDPOINT_SIZE + 4) 775 goto fail0; 776 777 /* we might need to change message format someday */ 778 if (copy_from_user (&tag, buf, 4)) { 779 goto fail1; 780 } 781 if (tag != 1) { 782 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag); 783 goto fail0; 784 } 785 buf += 4; 786 len -= 4; 787 788 /* NOTE: audio endpoint extensions not accepted here; 789 * just don't include the extra bytes. 790 */ 791 792 /* full/low speed descriptor, then high speed */ 793 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) { 794 goto fail1; 795 } 796 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE 797 || data->desc.bDescriptorType != USB_DT_ENDPOINT) 798 goto fail0; 799 if (len != USB_DT_ENDPOINT_SIZE) { 800 if (len != 2 * USB_DT_ENDPOINT_SIZE) 801 goto fail0; 802 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE, 803 USB_DT_ENDPOINT_SIZE)) { 804 goto fail1; 805 } 806 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE 807 || data->hs_desc.bDescriptorType 808 != USB_DT_ENDPOINT) { 809 DBG(data->dev, "config %s, bad hs length or type\n", 810 data->name); 811 goto fail0; 812 } 813 } 814 815 spin_lock_irq (&data->dev->lock); 816 if (data->dev->state == STATE_DEV_UNBOUND) { 817 value = -ENOENT; 818 goto gone; 819 } else if ((ep = data->ep) == NULL) { 820 value = -ENODEV; 821 goto gone; 822 } 823 switch (data->dev->gadget->speed) { 824 case USB_SPEED_LOW: 825 case USB_SPEED_FULL: 826 ep->desc = &data->desc; 827 value = usb_ep_enable(ep); 828 if (value == 0) 829 data->state = STATE_EP_ENABLED; 830 break; 831#ifdef CONFIG_USB_GADGET_DUALSPEED 832 case USB_SPEED_HIGH: 833 /* fails if caller didn't provide that descriptor... */ 834 ep->desc = &data->hs_desc; 835 value = usb_ep_enable(ep); 836 if (value == 0) 837 data->state = STATE_EP_ENABLED; 838 break; 839#endif 840 default: 841 DBG(data->dev, "unconnected, %s init abandoned\n", 842 data->name); 843 value = -EINVAL; 844 } 845 if (value == 0) { 846 fd->f_op = &ep_io_operations; 847 value = length; 848 } 849gone: 850 spin_unlock_irq (&data->dev->lock); 851 if (value < 0) { 852fail: 853 data->desc.bDescriptorType = 0; 854 data->hs_desc.bDescriptorType = 0; 855 } 856 mutex_unlock(&data->lock); 857 return value; 858fail0: 859 value = -EINVAL; 860 goto fail; 861fail1: 862 value = -EFAULT; 863 goto fail; 864} 865 866static int 867ep_open (struct inode *inode, struct file *fd) 868{ 869 struct ep_data *data = inode->i_private; 870 int value = -EBUSY; 871 872 if (mutex_lock_interruptible(&data->lock) != 0) 873 return -EINTR; 874 spin_lock_irq (&data->dev->lock); 875 if (data->dev->state == STATE_DEV_UNBOUND) 876 value = -ENOENT; 877 else if (data->state == STATE_EP_DISABLED) { 878 value = 0; 879 data->state = STATE_EP_READY; 880 get_ep (data); 881 fd->private_data = data; 882 VDEBUG (data->dev, "%s ready\n", data->name); 883 } else 884 DBG (data->dev, "%s state %d\n", 885 data->name, data->state); 886 spin_unlock_irq (&data->dev->lock); 887 mutex_unlock(&data->lock); 888 return value; 889} 890 891/* used before endpoint configuration */ 892static const struct file_operations ep_config_operations = { 893 .owner = THIS_MODULE, 894 .llseek = no_llseek, 895 896 .open = ep_open, 897 .write = ep_config, 898 .release = ep_release, 899}; 900 901/*----------------------------------------------------------------------*/ 902 903/* EP0 IMPLEMENTATION can be partly in userspace. 904 * 905 * Drivers that use this facility receive various events, including 906 * control requests the kernel doesn't handle. Drivers that don't 907 * use this facility may be too simple-minded for real applications. 908 */ 909 910static inline void ep0_readable (struct dev_data *dev) 911{ 912 wake_up (&dev->wait); 913 kill_fasync (&dev->fasync, SIGIO, POLL_IN); 914} 915 916static void clean_req (struct usb_ep *ep, struct usb_request *req) 917{ 918 struct dev_data *dev = ep->driver_data; 919 920 if (req->buf != dev->rbuf) { 921 kfree(req->buf); 922 req->buf = dev->rbuf; 923 req->dma = DMA_ADDR_INVALID; 924 } 925 req->complete = epio_complete; 926 dev->setup_out_ready = 0; 927} 928 929static void ep0_complete (struct usb_ep *ep, struct usb_request *req) 930{ 931 struct dev_data *dev = ep->driver_data; 932 unsigned long flags; 933 int free = 1; 934 935 /* for control OUT, data must still get to userspace */ 936 spin_lock_irqsave(&dev->lock, flags); 937 if (!dev->setup_in) { 938 dev->setup_out_error = (req->status != 0); 939 if (!dev->setup_out_error) 940 free = 0; 941 dev->setup_out_ready = 1; 942 ep0_readable (dev); 943 } 944 945 /* clean up as appropriate */ 946 if (free && req->buf != &dev->rbuf) 947 clean_req (ep, req); 948 req->complete = epio_complete; 949 spin_unlock_irqrestore(&dev->lock, flags); 950} 951 952static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len) 953{ 954 struct dev_data *dev = ep->driver_data; 955 956 if (dev->setup_out_ready) { 957 DBG (dev, "ep0 request busy!\n"); 958 return -EBUSY; 959 } 960 if (len > sizeof (dev->rbuf)) 961 req->buf = kmalloc(len, GFP_ATOMIC); 962 if (req->buf == NULL) { 963 req->buf = dev->rbuf; 964 return -ENOMEM; 965 } 966 req->complete = ep0_complete; 967 req->length = len; 968 req->zero = 0; 969 return 0; 970} 971 972static ssize_t 973ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) 974{ 975 struct dev_data *dev = fd->private_data; 976 ssize_t retval; 977 enum ep0_state state; 978 979 spin_lock_irq (&dev->lock); 980 981 /* report fd mode change before acting on it */ 982 if (dev->setup_abort) { 983 dev->setup_abort = 0; 984 retval = -EIDRM; 985 goto done; 986 } 987 988 /* control DATA stage */ 989 if ((state = dev->state) == STATE_DEV_SETUP) { 990 991 if (dev->setup_in) { /* stall IN */ 992 VDEBUG(dev, "ep0in stall\n"); 993 (void) usb_ep_set_halt (dev->gadget->ep0); 994 retval = -EL2HLT; 995 dev->state = STATE_DEV_CONNECTED; 996 997 } else if (len == 0) { /* ack SET_CONFIGURATION etc */ 998 struct usb_ep *ep = dev->gadget->ep0; 999 struct usb_request *req = dev->req; 1000 1001 if ((retval = setup_req (ep, req, 0)) == 0) 1002 retval = usb_ep_queue (ep, req, GFP_ATOMIC); 1003 dev->state = STATE_DEV_CONNECTED; 1004 1005 /* assume that was SET_CONFIGURATION */ 1006 if (dev->current_config) { 1007 unsigned power; 1008 1009 if (gadget_is_dualspeed(dev->gadget) 1010 && (dev->gadget->speed 1011 == USB_SPEED_HIGH)) 1012 power = dev->hs_config->bMaxPower; 1013 else 1014 power = dev->config->bMaxPower; 1015 usb_gadget_vbus_draw(dev->gadget, 2 * power); 1016 } 1017 1018 } else { /* collect OUT data */ 1019 if ((fd->f_flags & O_NONBLOCK) != 0 1020 && !dev->setup_out_ready) { 1021 retval = -EAGAIN; 1022 goto done; 1023 } 1024 spin_unlock_irq (&dev->lock); 1025 retval = wait_event_interruptible (dev->wait, 1026 dev->setup_out_ready != 0); 1027 1028 /* FIXME state could change from under us */ 1029 spin_lock_irq (&dev->lock); 1030 if (retval) 1031 goto done; 1032 1033 if (dev->state != STATE_DEV_SETUP) { 1034 retval = -ECANCELED; 1035 goto done; 1036 } 1037 dev->state = STATE_DEV_CONNECTED; 1038 1039 if (dev->setup_out_error) 1040 retval = -EIO; 1041 else { 1042 len = min (len, (size_t)dev->req->actual); 1043// FIXME don't call this with the spinlock held ... 1044 if (copy_to_user (buf, dev->req->buf, len)) 1045 retval = -EFAULT; 1046 clean_req (dev->gadget->ep0, dev->req); 1047 /* NOTE userspace can't yet choose to stall */ 1048 } 1049 } 1050 goto done; 1051 } 1052 1053 /* else normal: return event data */ 1054 if (len < sizeof dev->event [0]) { 1055 retval = -EINVAL; 1056 goto done; 1057 } 1058 len -= len % sizeof (struct usb_gadgetfs_event); 1059 dev->usermode_setup = 1; 1060 1061scan: 1062 /* return queued events right away */ 1063 if (dev->ev_next != 0) { 1064 unsigned i, n; 1065 1066 n = len / sizeof (struct usb_gadgetfs_event); 1067 if (dev->ev_next < n) 1068 n = dev->ev_next; 1069 1070 /* ep0 i/o has special semantics during STATE_DEV_SETUP */ 1071 for (i = 0; i < n; i++) { 1072 if (dev->event [i].type == GADGETFS_SETUP) { 1073 dev->state = STATE_DEV_SETUP; 1074 n = i + 1; 1075 break; 1076 } 1077 } 1078 spin_unlock_irq (&dev->lock); 1079 len = n * sizeof (struct usb_gadgetfs_event); 1080 if (copy_to_user (buf, &dev->event, len)) 1081 retval = -EFAULT; 1082 else 1083 retval = len; 1084 if (len > 0) { 1085 /* NOTE this doesn't guard against broken drivers; 1086 * concurrent ep0 readers may lose events. 1087 */ 1088 spin_lock_irq (&dev->lock); 1089 if (dev->ev_next > n) { 1090 memmove(&dev->event[0], &dev->event[n], 1091 sizeof (struct usb_gadgetfs_event) 1092 * (dev->ev_next - n)); 1093 } 1094 dev->ev_next -= n; 1095 spin_unlock_irq (&dev->lock); 1096 } 1097 return retval; 1098 } 1099 if (fd->f_flags & O_NONBLOCK) { 1100 retval = -EAGAIN; 1101 goto done; 1102 } 1103 1104 switch (state) { 1105 default: 1106 DBG (dev, "fail %s, state %d\n", __func__, state); 1107 retval = -ESRCH; 1108 break; 1109 case STATE_DEV_UNCONNECTED: 1110 case STATE_DEV_CONNECTED: 1111 spin_unlock_irq (&dev->lock); 1112 DBG (dev, "%s wait\n", __func__); 1113 1114 /* wait for events */ 1115 retval = wait_event_interruptible (dev->wait, 1116 dev->ev_next != 0); 1117 if (retval < 0) 1118 return retval; 1119 spin_lock_irq (&dev->lock); 1120 goto scan; 1121 } 1122 1123done: 1124 spin_unlock_irq (&dev->lock); 1125 return retval; 1126} 1127 1128static struct usb_gadgetfs_event * 1129next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type) 1130{ 1131 struct usb_gadgetfs_event *event; 1132 unsigned i; 1133 1134 switch (type) { 1135 /* these events purge the queue */ 1136 case GADGETFS_DISCONNECT: 1137 if (dev->state == STATE_DEV_SETUP) 1138 dev->setup_abort = 1; 1139 // FALL THROUGH 1140 case GADGETFS_CONNECT: 1141 dev->ev_next = 0; 1142 break; 1143 case GADGETFS_SETUP: /* previous request timed out */ 1144 case GADGETFS_SUSPEND: /* same effect */ 1145 /* these events can't be repeated */ 1146 for (i = 0; i != dev->ev_next; i++) { 1147 if (dev->event [i].type != type) 1148 continue; 1149 DBG(dev, "discard old event[%d] %d\n", i, type); 1150 dev->ev_next--; 1151 if (i == dev->ev_next) 1152 break; 1153 /* indices start at zero, for simplicity */ 1154 memmove (&dev->event [i], &dev->event [i + 1], 1155 sizeof (struct usb_gadgetfs_event) 1156 * (dev->ev_next - i)); 1157 } 1158 break; 1159 default: 1160 BUG (); 1161 } 1162 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type); 1163 event = &dev->event [dev->ev_next++]; 1164 BUG_ON (dev->ev_next > N_EVENT); 1165 memset (event, 0, sizeof *event); 1166 event->type = type; 1167 return event; 1168} 1169 1170static ssize_t 1171ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 1172{ 1173 struct dev_data *dev = fd->private_data; 1174 ssize_t retval = -ESRCH; 1175 1176 spin_lock_irq (&dev->lock); 1177 1178 /* report fd mode change before acting on it */ 1179 if (dev->setup_abort) { 1180 dev->setup_abort = 0; 1181 retval = -EIDRM; 1182 1183 /* data and/or status stage for control request */ 1184 } else if (dev->state == STATE_DEV_SETUP) { 1185 1186 /* IN DATA+STATUS caller makes len <= wLength */ 1187 if (dev->setup_in) { 1188 retval = setup_req (dev->gadget->ep0, dev->req, len); 1189 if (retval == 0) { 1190 dev->state = STATE_DEV_CONNECTED; 1191 spin_unlock_irq (&dev->lock); 1192 if (copy_from_user (dev->req->buf, buf, len)) 1193 retval = -EFAULT; 1194 else { 1195 if (len < dev->setup_wLength) 1196 dev->req->zero = 1; 1197 retval = usb_ep_queue ( 1198 dev->gadget->ep0, dev->req, 1199 GFP_KERNEL); 1200 } 1201 if (retval < 0) { 1202 spin_lock_irq (&dev->lock); 1203 clean_req (dev->gadget->ep0, dev->req); 1204 spin_unlock_irq (&dev->lock); 1205 } else 1206 retval = len; 1207 1208 return retval; 1209 } 1210 1211 /* can stall some OUT transfers */ 1212 } else if (dev->setup_can_stall) { 1213 VDEBUG(dev, "ep0out stall\n"); 1214 (void) usb_ep_set_halt (dev->gadget->ep0); 1215 retval = -EL2HLT; 1216 dev->state = STATE_DEV_CONNECTED; 1217 } else { 1218 DBG(dev, "bogus ep0out stall!\n"); 1219 } 1220 } else 1221 DBG (dev, "fail %s, state %d\n", __func__, dev->state); 1222 1223 spin_unlock_irq (&dev->lock); 1224 return retval; 1225} 1226 1227static int 1228ep0_fasync (int f, struct file *fd, int on) 1229{ 1230 struct dev_data *dev = fd->private_data; 1231 // caller must F_SETOWN before signal delivery happens 1232 VDEBUG (dev, "%s %s\n", __func__, on ? "on" : "off"); 1233 return fasync_helper (f, fd, on, &dev->fasync); 1234} 1235 1236static struct usb_gadget_driver gadgetfs_driver; 1237 1238static int 1239dev_release (struct inode *inode, struct file *fd) 1240{ 1241 struct dev_data *dev = fd->private_data; 1242 1243 /* closing ep0 === shutdown all */ 1244 1245 usb_gadget_unregister_driver (&gadgetfs_driver); 1246 1247 /* at this point "good" hardware has disconnected the 1248 * device from USB; the host won't see it any more. 1249 * alternatively, all host requests will time out. 1250 */ 1251 1252 kfree (dev->buf); 1253 dev->buf = NULL; 1254 put_dev (dev); 1255 1256 /* other endpoints were all decoupled from this device */ 1257 spin_lock_irq(&dev->lock); 1258 dev->state = STATE_DEV_DISABLED; 1259 spin_unlock_irq(&dev->lock); 1260 return 0; 1261} 1262 1263static unsigned int 1264ep0_poll (struct file *fd, poll_table *wait) 1265{ 1266 struct dev_data *dev = fd->private_data; 1267 int mask = 0; 1268 1269 poll_wait(fd, &dev->wait, wait); 1270 1271 spin_lock_irq (&dev->lock); 1272 1273 /* report fd mode change before acting on it */ 1274 if (dev->setup_abort) { 1275 dev->setup_abort = 0; 1276 mask = POLLHUP; 1277 goto out; 1278 } 1279 1280 if (dev->state == STATE_DEV_SETUP) { 1281 if (dev->setup_in || dev->setup_can_stall) 1282 mask = POLLOUT; 1283 } else { 1284 if (dev->ev_next != 0) 1285 mask = POLLIN; 1286 } 1287out: 1288 spin_unlock_irq(&dev->lock); 1289 return mask; 1290} 1291 1292static long dev_ioctl (struct file *fd, unsigned code, unsigned long value) 1293{ 1294 struct dev_data *dev = fd->private_data; 1295 struct usb_gadget *gadget = dev->gadget; 1296 long ret = -ENOTTY; 1297 1298 if (gadget->ops->ioctl) 1299 ret = gadget->ops->ioctl (gadget, code, value); 1300 1301 return ret; 1302} 1303 1304/* used after device configuration */ 1305static const struct file_operations ep0_io_operations = { 1306 .owner = THIS_MODULE, 1307 .llseek = no_llseek, 1308 1309 .read = ep0_read, 1310 .write = ep0_write, 1311 .fasync = ep0_fasync, 1312 .poll = ep0_poll, 1313 .unlocked_ioctl = dev_ioctl, 1314 .release = dev_release, 1315}; 1316 1317/*----------------------------------------------------------------------*/ 1318 1319/* The in-kernel gadget driver handles most ep0 issues, in particular 1320 * enumerating the single configuration (as provided from user space). 1321 * 1322 * Unrecognized ep0 requests may be handled in user space. 1323 */ 1324 1325#ifdef CONFIG_USB_GADGET_DUALSPEED 1326static void make_qualifier (struct dev_data *dev) 1327{ 1328 struct usb_qualifier_descriptor qual; 1329 struct usb_device_descriptor *desc; 1330 1331 qual.bLength = sizeof qual; 1332 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER; 1333 qual.bcdUSB = cpu_to_le16 (0x0200); 1334 1335 desc = dev->dev; 1336 qual.bDeviceClass = desc->bDeviceClass; 1337 qual.bDeviceSubClass = desc->bDeviceSubClass; 1338 qual.bDeviceProtocol = desc->bDeviceProtocol; 1339 1340 /* assumes ep0 uses the same value for both speeds ... */ 1341 qual.bMaxPacketSize0 = dev->gadget->ep0->maxpacket; 1342 1343 qual.bNumConfigurations = 1; 1344 qual.bRESERVED = 0; 1345 1346 memcpy (dev->rbuf, &qual, sizeof qual); 1347} 1348#endif 1349 1350static int 1351config_buf (struct dev_data *dev, u8 type, unsigned index) 1352{ 1353 int len; 1354 int hs = 0; 1355 1356 /* only one configuration */ 1357 if (index > 0) 1358 return -EINVAL; 1359 1360 if (gadget_is_dualspeed(dev->gadget)) { 1361 hs = (dev->gadget->speed == USB_SPEED_HIGH); 1362 if (type == USB_DT_OTHER_SPEED_CONFIG) 1363 hs = !hs; 1364 } 1365 if (hs) { 1366 dev->req->buf = dev->hs_config; 1367 len = le16_to_cpu(dev->hs_config->wTotalLength); 1368 } else { 1369 dev->req->buf = dev->config; 1370 len = le16_to_cpu(dev->config->wTotalLength); 1371 } 1372 ((u8 *)dev->req->buf) [1] = type; 1373 return len; 1374} 1375 1376static int 1377gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) 1378{ 1379 struct dev_data *dev = get_gadget_data (gadget); 1380 struct usb_request *req = dev->req; 1381 int value = -EOPNOTSUPP; 1382 struct usb_gadgetfs_event *event; 1383 u16 w_value = le16_to_cpu(ctrl->wValue); 1384 u16 w_length = le16_to_cpu(ctrl->wLength); 1385 1386 spin_lock (&dev->lock); 1387 dev->setup_abort = 0; 1388 if (dev->state == STATE_DEV_UNCONNECTED) { 1389 if (gadget_is_dualspeed(gadget) 1390 && gadget->speed == USB_SPEED_HIGH 1391 && dev->hs_config == NULL) { 1392 spin_unlock(&dev->lock); 1393 ERROR (dev, "no high speed config??\n"); 1394 return -EINVAL; 1395 } 1396 1397 dev->state = STATE_DEV_CONNECTED; 1398 1399 INFO (dev, "connected\n"); 1400 event = next_event (dev, GADGETFS_CONNECT); 1401 event->u.speed = gadget->speed; 1402 ep0_readable (dev); 1403 1404 /* host may have given up waiting for response. we can miss control 1405 * requests handled lower down (device/endpoint status and features); 1406 * then ep0_{read,write} will report the wrong status. controller 1407 * driver will have aborted pending i/o. 1408 */ 1409 } else if (dev->state == STATE_DEV_SETUP) 1410 dev->setup_abort = 1; 1411 1412 req->buf = dev->rbuf; 1413 req->dma = DMA_ADDR_INVALID; 1414 req->context = NULL; 1415 value = -EOPNOTSUPP; 1416 switch (ctrl->bRequest) { 1417 1418 case USB_REQ_GET_DESCRIPTOR: 1419 if (ctrl->bRequestType != USB_DIR_IN) 1420 goto unrecognized; 1421 switch (w_value >> 8) { 1422 1423 case USB_DT_DEVICE: 1424 value = min (w_length, (u16) sizeof *dev->dev); 1425 dev->dev->bMaxPacketSize0 = dev->gadget->ep0->maxpacket; 1426 req->buf = dev->dev; 1427 break; 1428#ifdef CONFIG_USB_GADGET_DUALSPEED 1429 case USB_DT_DEVICE_QUALIFIER: 1430 if (!dev->hs_config) 1431 break; 1432 value = min (w_length, (u16) 1433 sizeof (struct usb_qualifier_descriptor)); 1434 make_qualifier (dev); 1435 break; 1436 case USB_DT_OTHER_SPEED_CONFIG: 1437 // FALLTHROUGH 1438#endif 1439 case USB_DT_CONFIG: 1440 value = config_buf (dev, 1441 w_value >> 8, 1442 w_value & 0xff); 1443 if (value >= 0) 1444 value = min (w_length, (u16) value); 1445 break; 1446 case USB_DT_STRING: 1447 goto unrecognized; 1448 1449 default: // all others are errors 1450 break; 1451 } 1452 break; 1453 1454 /* currently one config, two speeds */ 1455 case USB_REQ_SET_CONFIGURATION: 1456 if (ctrl->bRequestType != 0) 1457 goto unrecognized; 1458 if (0 == (u8) w_value) { 1459 value = 0; 1460 dev->current_config = 0; 1461 usb_gadget_vbus_draw(gadget, 8 /* mA */ ); 1462 // user mode expected to disable endpoints 1463 } else { 1464 u8 config, power; 1465 1466 if (gadget_is_dualspeed(gadget) 1467 && gadget->speed == USB_SPEED_HIGH) { 1468 config = dev->hs_config->bConfigurationValue; 1469 power = dev->hs_config->bMaxPower; 1470 } else { 1471 config = dev->config->bConfigurationValue; 1472 power = dev->config->bMaxPower; 1473 } 1474 1475 if (config == (u8) w_value) { 1476 value = 0; 1477 dev->current_config = config; 1478 usb_gadget_vbus_draw(gadget, 2 * power); 1479 } 1480 } 1481 1482 /* report SET_CONFIGURATION like any other control request, 1483 * except that usermode may not stall this. the next 1484 * request mustn't be allowed start until this finishes: 1485 * endpoints and threads set up, etc. 1486 * 1487 * NOTE: older PXA hardware (before PXA 255: without UDCCFR) 1488 * has bad/racey automagic that prevents synchronizing here. 1489 * even kernel mode drivers often miss them. 1490 */ 1491 if (value == 0) { 1492 INFO (dev, "configuration #%d\n", dev->current_config); 1493 if (dev->usermode_setup) { 1494 dev->setup_can_stall = 0; 1495 goto delegate; 1496 } 1497 } 1498 break; 1499 1500#ifndef CONFIG_USB_GADGET_PXA25X 1501 /* PXA automagically handles this request too */ 1502 case USB_REQ_GET_CONFIGURATION: 1503 if (ctrl->bRequestType != 0x80) 1504 goto unrecognized; 1505 *(u8 *)req->buf = dev->current_config; 1506 value = min (w_length, (u16) 1); 1507 break; 1508#endif 1509 1510 default: 1511unrecognized: 1512 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n", 1513 dev->usermode_setup ? "delegate" : "fail", 1514 ctrl->bRequestType, ctrl->bRequest, 1515 w_value, le16_to_cpu(ctrl->wIndex), w_length); 1516 1517 /* if there's an ep0 reader, don't stall */ 1518 if (dev->usermode_setup) { 1519 dev->setup_can_stall = 1; 1520delegate: 1521 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN) 1522 ? 1 : 0; 1523 dev->setup_wLength = w_length; 1524 dev->setup_out_ready = 0; 1525 dev->setup_out_error = 0; 1526 value = 0; 1527 1528 /* read DATA stage for OUT right away */ 1529 if (unlikely (!dev->setup_in && w_length)) { 1530 value = setup_req (gadget->ep0, dev->req, 1531 w_length); 1532 if (value < 0) 1533 break; 1534 value = usb_ep_queue (gadget->ep0, dev->req, 1535 GFP_ATOMIC); 1536 if (value < 0) { 1537 clean_req (gadget->ep0, dev->req); 1538 break; 1539 } 1540 1541 /* we can't currently stall these */ 1542 dev->setup_can_stall = 0; 1543 } 1544 1545 /* state changes when reader collects event */ 1546 event = next_event (dev, GADGETFS_SETUP); 1547 event->u.setup = *ctrl; 1548 ep0_readable (dev); 1549 spin_unlock (&dev->lock); 1550 return 0; 1551 } 1552 } 1553 1554 /* proceed with data transfer and status phases? */ 1555 if (value >= 0 && dev->state != STATE_DEV_SETUP) { 1556 req->length = value; 1557 req->zero = value < w_length; 1558 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC); 1559 if (value < 0) { 1560 DBG (dev, "ep_queue --> %d\n", value); 1561 req->status = 0; 1562 } 1563 } 1564 1565 /* device stalls when value < 0 */ 1566 spin_unlock (&dev->lock); 1567 return value; 1568} 1569 1570static void destroy_ep_files (struct dev_data *dev) 1571{ 1572 struct list_head *entry, *tmp; 1573 1574 DBG (dev, "%s %d\n", __func__, dev->state); 1575 1576 /* dev->state must prevent interference */ 1577restart: 1578 spin_lock_irq (&dev->lock); 1579 list_for_each_safe (entry, tmp, &dev->epfiles) { 1580 struct ep_data *ep; 1581 struct inode *parent; 1582 struct dentry *dentry; 1583 1584 /* break link to FS */ 1585 ep = list_entry (entry, struct ep_data, epfiles); 1586 list_del_init (&ep->epfiles); 1587 dentry = ep->dentry; 1588 ep->dentry = NULL; 1589 parent = dentry->d_parent->d_inode; 1590 1591 /* break link to controller */ 1592 if (ep->state == STATE_EP_ENABLED) 1593 (void) usb_ep_disable (ep->ep); 1594 ep->state = STATE_EP_UNBOUND; 1595 usb_ep_free_request (ep->ep, ep->req); 1596 ep->ep = NULL; 1597 wake_up (&ep->wait); 1598 put_ep (ep); 1599 1600 spin_unlock_irq (&dev->lock); 1601 1602 /* break link to dcache */ 1603 mutex_lock (&parent->i_mutex); 1604 d_delete (dentry); 1605 dput (dentry); 1606 mutex_unlock (&parent->i_mutex); 1607 1608 /* fds may still be open */ 1609 goto restart; 1610 } 1611 spin_unlock_irq (&dev->lock); 1612} 1613 1614 1615static struct inode * 1616gadgetfs_create_file (struct super_block *sb, char const *name, 1617 void *data, const struct file_operations *fops, 1618 struct dentry **dentry_p); 1619 1620static int activate_ep_files (struct dev_data *dev) 1621{ 1622 struct usb_ep *ep; 1623 struct ep_data *data; 1624 1625 gadget_for_each_ep (ep, dev->gadget) { 1626 1627 data = kzalloc(sizeof(*data), GFP_KERNEL); 1628 if (!data) 1629 goto enomem0; 1630 data->state = STATE_EP_DISABLED; 1631 mutex_init(&data->lock); 1632 init_waitqueue_head (&data->wait); 1633 1634 strncpy (data->name, ep->name, sizeof (data->name) - 1); 1635 atomic_set (&data->count, 1); 1636 data->dev = dev; 1637 get_dev (dev); 1638 1639 data->ep = ep; 1640 ep->driver_data = data; 1641 1642 data->req = usb_ep_alloc_request (ep, GFP_KERNEL); 1643 if (!data->req) 1644 goto enomem1; 1645 1646 data->inode = gadgetfs_create_file (dev->sb, data->name, 1647 data, &ep_config_operations, 1648 &data->dentry); 1649 if (!data->inode) 1650 goto enomem2; 1651 list_add_tail (&data->epfiles, &dev->epfiles); 1652 } 1653 return 0; 1654 1655enomem2: 1656 usb_ep_free_request (ep, data->req); 1657enomem1: 1658 put_dev (dev); 1659 kfree (data); 1660enomem0: 1661 DBG (dev, "%s enomem\n", __func__); 1662 destroy_ep_files (dev); 1663 return -ENOMEM; 1664} 1665 1666static void 1667gadgetfs_unbind (struct usb_gadget *gadget) 1668{ 1669 struct dev_data *dev = get_gadget_data (gadget); 1670 1671 DBG (dev, "%s\n", __func__); 1672 1673 spin_lock_irq (&dev->lock); 1674 dev->state = STATE_DEV_UNBOUND; 1675 spin_unlock_irq (&dev->lock); 1676 1677 destroy_ep_files (dev); 1678 gadget->ep0->driver_data = NULL; 1679 set_gadget_data (gadget, NULL); 1680 1681 /* we've already been disconnected ... no i/o is active */ 1682 if (dev->req) 1683 usb_ep_free_request (gadget->ep0, dev->req); 1684 DBG (dev, "%s done\n", __func__); 1685 put_dev (dev); 1686} 1687 1688static struct dev_data *the_device; 1689 1690static int 1691gadgetfs_bind (struct usb_gadget *gadget) 1692{ 1693 struct dev_data *dev = the_device; 1694 1695 if (!dev) 1696 return -ESRCH; 1697 if (0 != strcmp (CHIP, gadget->name)) { 1698 pr_err("%s expected %s controller not %s\n", 1699 shortname, CHIP, gadget->name); 1700 return -ENODEV; 1701 } 1702 1703 set_gadget_data (gadget, dev); 1704 dev->gadget = gadget; 1705 gadget->ep0->driver_data = dev; 1706 1707 /* preallocate control response and buffer */ 1708 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL); 1709 if (!dev->req) 1710 goto enomem; 1711 dev->req->context = NULL; 1712 dev->req->complete = epio_complete; 1713 1714 if (activate_ep_files (dev) < 0) 1715 goto enomem; 1716 1717 INFO (dev, "bound to %s driver\n", gadget->name); 1718 spin_lock_irq(&dev->lock); 1719 dev->state = STATE_DEV_UNCONNECTED; 1720 spin_unlock_irq(&dev->lock); 1721 get_dev (dev); 1722 return 0; 1723 1724enomem: 1725 gadgetfs_unbind (gadget); 1726 return -ENOMEM; 1727} 1728 1729static void 1730gadgetfs_disconnect (struct usb_gadget *gadget) 1731{ 1732 struct dev_data *dev = get_gadget_data (gadget); 1733 unsigned long flags; 1734 1735 spin_lock_irqsave (&dev->lock, flags); 1736 if (dev->state == STATE_DEV_UNCONNECTED) 1737 goto exit; 1738 dev->state = STATE_DEV_UNCONNECTED; 1739 1740 INFO (dev, "disconnected\n"); 1741 next_event (dev, GADGETFS_DISCONNECT); 1742 ep0_readable (dev); 1743exit: 1744 spin_unlock_irqrestore (&dev->lock, flags); 1745} 1746 1747static void 1748gadgetfs_suspend (struct usb_gadget *gadget) 1749{ 1750 struct dev_data *dev = get_gadget_data (gadget); 1751 1752 INFO (dev, "suspended from state %d\n", dev->state); 1753 spin_lock (&dev->lock); 1754 switch (dev->state) { 1755 case STATE_DEV_SETUP: // VERY odd... host died?? 1756 case STATE_DEV_CONNECTED: 1757 case STATE_DEV_UNCONNECTED: 1758 next_event (dev, GADGETFS_SUSPEND); 1759 ep0_readable (dev); 1760 /* FALLTHROUGH */ 1761 default: 1762 break; 1763 } 1764 spin_unlock (&dev->lock); 1765} 1766 1767static struct usb_gadget_driver gadgetfs_driver = { 1768#ifdef CONFIG_USB_GADGET_DUALSPEED 1769 .max_speed = USB_SPEED_HIGH, 1770#else 1771 .max_speed = USB_SPEED_FULL, 1772#endif 1773 .function = (char *) driver_desc, 1774 .unbind = gadgetfs_unbind, 1775 .setup = gadgetfs_setup, 1776 .disconnect = gadgetfs_disconnect, 1777 .suspend = gadgetfs_suspend, 1778 1779 .driver = { 1780 .name = (char *) shortname, 1781 }, 1782}; 1783 1784/*----------------------------------------------------------------------*/ 1785 1786static void gadgetfs_nop(struct usb_gadget *arg) { } 1787 1788static int gadgetfs_probe (struct usb_gadget *gadget) 1789{ 1790 CHIP = gadget->name; 1791 return -EISNAM; 1792} 1793 1794static struct usb_gadget_driver probe_driver = { 1795 .max_speed = USB_SPEED_HIGH, 1796 .unbind = gadgetfs_nop, 1797 .setup = (void *)gadgetfs_nop, 1798 .disconnect = gadgetfs_nop, 1799 .driver = { 1800 .name = "nop", 1801 }, 1802}; 1803 1804 1805/* DEVICE INITIALIZATION 1806 * 1807 * fd = open ("/dev/gadget/$CHIP", O_RDWR) 1808 * status = write (fd, descriptors, sizeof descriptors) 1809 * 1810 * That write establishes the device configuration, so the kernel can 1811 * bind to the controller ... guaranteeing it can handle enumeration 1812 * at all necessary speeds. Descriptor order is: 1813 * 1814 * . message tag (u32, host order) ... for now, must be zero; it 1815 * would change to support features like multi-config devices 1816 * . full/low speed config ... all wTotalLength bytes (with interface, 1817 * class, altsetting, endpoint, and other descriptors) 1818 * . high speed config ... all descriptors, for high speed operation; 1819 * this one's optional except for high-speed hardware 1820 * . device descriptor 1821 * 1822 * Endpoints are not yet enabled. Drivers must wait until device 1823 * configuration and interface altsetting changes create 1824 * the need to configure (or unconfigure) them. 1825 * 1826 * After initialization, the device stays active for as long as that 1827 * $CHIP file is open. Events must then be read from that descriptor, 1828 * such as configuration notifications. 1829 */ 1830 1831static int is_valid_config (struct usb_config_descriptor *config) 1832{ 1833 return config->bDescriptorType == USB_DT_CONFIG 1834 && config->bLength == USB_DT_CONFIG_SIZE 1835 && config->bConfigurationValue != 0 1836 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0 1837 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0; 1838 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */ 1839 /* FIXME check lengths: walk to end */ 1840} 1841 1842static ssize_t 1843dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 1844{ 1845 struct dev_data *dev = fd->private_data; 1846 ssize_t value = len, length = len; 1847 unsigned total; 1848 u32 tag; 1849 char *kbuf; 1850 1851 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) 1852 return -EINVAL; 1853 1854 /* we might need to change message format someday */ 1855 if (copy_from_user (&tag, buf, 4)) 1856 return -EFAULT; 1857 if (tag != 0) 1858 return -EINVAL; 1859 buf += 4; 1860 length -= 4; 1861 1862 kbuf = memdup_user(buf, length); 1863 if (IS_ERR(kbuf)) 1864 return PTR_ERR(kbuf); 1865 1866 spin_lock_irq (&dev->lock); 1867 value = -EINVAL; 1868 if (dev->buf) 1869 goto fail; 1870 dev->buf = kbuf; 1871 1872 /* full or low speed config */ 1873 dev->config = (void *) kbuf; 1874 total = le16_to_cpu(dev->config->wTotalLength); 1875 if (!is_valid_config (dev->config) || total >= length) 1876 goto fail; 1877 kbuf += total; 1878 length -= total; 1879 1880 /* optional high speed config */ 1881 if (kbuf [1] == USB_DT_CONFIG) { 1882 dev->hs_config = (void *) kbuf; 1883 total = le16_to_cpu(dev->hs_config->wTotalLength); 1884 if (!is_valid_config (dev->hs_config) || total >= length) 1885 goto fail; 1886 kbuf += total; 1887 length -= total; 1888 } 1889 1890 /* could support multiple configs, using another encoding! */ 1891 1892 /* device descriptor (tweaked for paranoia) */ 1893 if (length != USB_DT_DEVICE_SIZE) 1894 goto fail; 1895 dev->dev = (void *)kbuf; 1896 if (dev->dev->bLength != USB_DT_DEVICE_SIZE 1897 || dev->dev->bDescriptorType != USB_DT_DEVICE 1898 || dev->dev->bNumConfigurations != 1) 1899 goto fail; 1900 dev->dev->bNumConfigurations = 1; 1901 dev->dev->bcdUSB = cpu_to_le16 (0x0200); 1902 1903 /* triggers gadgetfs_bind(); then we can enumerate. */ 1904 spin_unlock_irq (&dev->lock); 1905 value = usb_gadget_probe_driver(&gadgetfs_driver, gadgetfs_bind); 1906 if (value != 0) { 1907 kfree (dev->buf); 1908 dev->buf = NULL; 1909 } else { 1910 /* at this point "good" hardware has for the first time 1911 * let the USB the host see us. alternatively, if users 1912 * unplug/replug that will clear all the error state. 1913 * 1914 * note: everything running before here was guaranteed 1915 * to choke driver model style diagnostics. from here 1916 * on, they can work ... except in cleanup paths that 1917 * kick in after the ep0 descriptor is closed. 1918 */ 1919 fd->f_op = &ep0_io_operations; 1920 value = len; 1921 } 1922 return value; 1923 1924fail: 1925 spin_unlock_irq (&dev->lock); 1926 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __func__, value, dev); 1927 kfree (dev->buf); 1928 dev->buf = NULL; 1929 return value; 1930} 1931 1932static int 1933dev_open (struct inode *inode, struct file *fd) 1934{ 1935 struct dev_data *dev = inode->i_private; 1936 int value = -EBUSY; 1937 1938 spin_lock_irq(&dev->lock); 1939 if (dev->state == STATE_DEV_DISABLED) { 1940 dev->ev_next = 0; 1941 dev->state = STATE_DEV_OPENED; 1942 fd->private_data = dev; 1943 get_dev (dev); 1944 value = 0; 1945 } 1946 spin_unlock_irq(&dev->lock); 1947 return value; 1948} 1949 1950static const struct file_operations dev_init_operations = { 1951 .owner = THIS_MODULE, 1952 .llseek = no_llseek, 1953 1954 .open = dev_open, 1955 .write = dev_config, 1956 .fasync = ep0_fasync, 1957 .unlocked_ioctl = dev_ioctl, 1958 .release = dev_release, 1959}; 1960 1961/*----------------------------------------------------------------------*/ 1962 1963/* FILESYSTEM AND SUPERBLOCK OPERATIONS 1964 * 1965 * Mounting the filesystem creates a controller file, used first for 1966 * device configuration then later for event monitoring. 1967 */ 1968 1969 1970/* FIXME PAM etc could set this security policy without mount options 1971 * if epfiles inherited ownership and permissons from ep0 ... 1972 */ 1973 1974static unsigned default_uid; 1975static unsigned default_gid; 1976static unsigned default_perm = S_IRUSR | S_IWUSR; 1977 1978module_param (default_uid, uint, 0644); 1979module_param (default_gid, uint, 0644); 1980module_param (default_perm, uint, 0644); 1981 1982 1983static struct inode * 1984gadgetfs_make_inode (struct super_block *sb, 1985 void *data, const struct file_operations *fops, 1986 int mode) 1987{ 1988 struct inode *inode = new_inode (sb); 1989 1990 if (inode) { 1991 inode->i_ino = get_next_ino(); 1992 inode->i_mode = mode; 1993 inode->i_uid = default_uid; 1994 inode->i_gid = default_gid; 1995 inode->i_atime = inode->i_mtime = inode->i_ctime 1996 = CURRENT_TIME; 1997 inode->i_private = data; 1998 inode->i_fop = fops; 1999 } 2000 return inode; 2001} 2002 2003/* creates in fs root directory, so non-renamable and non-linkable. 2004 * so inode and dentry are paired, until device reconfig. 2005 */ 2006static struct inode * 2007gadgetfs_create_file (struct super_block *sb, char const *name, 2008 void *data, const struct file_operations *fops, 2009 struct dentry **dentry_p) 2010{ 2011 struct dentry *dentry; 2012 struct inode *inode; 2013 2014 dentry = d_alloc_name(sb->s_root, name); 2015 if (!dentry) 2016 return NULL; 2017 2018 inode = gadgetfs_make_inode (sb, data, fops, 2019 S_IFREG | (default_perm & S_IRWXUGO)); 2020 if (!inode) { 2021 dput(dentry); 2022 return NULL; 2023 } 2024 d_add (dentry, inode); 2025 *dentry_p = dentry; 2026 return inode; 2027} 2028 2029static const struct super_operations gadget_fs_operations = { 2030 .statfs = simple_statfs, 2031 .drop_inode = generic_delete_inode, 2032}; 2033 2034static int 2035gadgetfs_fill_super (struct super_block *sb, void *opts, int silent) 2036{ 2037 struct inode *inode; 2038 struct dev_data *dev; 2039 2040 if (the_device) 2041 return -ESRCH; 2042 2043 /* fake probe to determine $CHIP */ 2044 (void) usb_gadget_probe_driver(&probe_driver, gadgetfs_probe); 2045 if (!CHIP) 2046 return -ENODEV; 2047 2048 /* superblock */ 2049 sb->s_blocksize = PAGE_CACHE_SIZE; 2050 sb->s_blocksize_bits = PAGE_CACHE_SHIFT; 2051 sb->s_magic = GADGETFS_MAGIC; 2052 sb->s_op = &gadget_fs_operations; 2053 sb->s_time_gran = 1; 2054 2055 /* root inode */ 2056 inode = gadgetfs_make_inode (sb, 2057 NULL, &simple_dir_operations, 2058 S_IFDIR | S_IRUGO | S_IXUGO); 2059 if (!inode) 2060 goto Enomem; 2061 inode->i_op = &simple_dir_inode_operations; 2062 if (!(sb->s_root = d_alloc_root (inode))) { 2063 iput(inode); 2064 goto Enomem; 2065 } 2066 2067 /* the ep0 file is named after the controller we expect; 2068 * user mode code can use it for sanity checks, like we do. 2069 */ 2070 dev = dev_new (); 2071 if (!dev) 2072 goto Enomem; 2073 2074 dev->sb = sb; 2075 if (!gadgetfs_create_file (sb, CHIP, 2076 dev, &dev_init_operations, 2077 &dev->dentry)) { 2078 put_dev(dev); 2079 goto Enomem; 2080 } 2081 2082 /* other endpoint files are available after hardware setup, 2083 * from binding to a controller. 2084 */ 2085 the_device = dev; 2086 return 0; 2087 2088Enomem: 2089 return -ENOMEM; 2090} 2091 2092/* "mount -t gadgetfs path /dev/gadget" ends up here */ 2093static struct dentry * 2094gadgetfs_mount (struct file_system_type *t, int flags, 2095 const char *path, void *opts) 2096{ 2097 return mount_single (t, flags, opts, gadgetfs_fill_super); 2098} 2099 2100static void 2101gadgetfs_kill_sb (struct super_block *sb) 2102{ 2103 kill_litter_super (sb); 2104 if (the_device) { 2105 put_dev (the_device); 2106 the_device = NULL; 2107 } 2108} 2109 2110/*----------------------------------------------------------------------*/ 2111 2112static struct file_system_type gadgetfs_type = { 2113 .owner = THIS_MODULE, 2114 .name = shortname, 2115 .mount = gadgetfs_mount, 2116 .kill_sb = gadgetfs_kill_sb, 2117}; 2118 2119/*----------------------------------------------------------------------*/ 2120 2121static int __init init (void) 2122{ 2123 int status; 2124 2125 status = register_filesystem (&gadgetfs_type); 2126 if (status == 0) 2127 pr_info ("%s: %s, version " DRIVER_VERSION "\n", 2128 shortname, driver_desc); 2129 return status; 2130} 2131module_init (init); 2132 2133static void __exit cleanup (void) 2134{ 2135 pr_debug ("unregister %s\n", shortname); 2136 unregister_filesystem (&gadgetfs_type); 2137} 2138module_exit (cleanup); 2139 2140