inode.c revision 7489d14943181731ef8694e2ea2d5a919b93b956
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 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 22 23// #define DEBUG /* data to help fault diagnosis */ 24// #define VERBOSE /* extra debug messages (success too) */ 25 26#include <linux/init.h> 27#include <linux/module.h> 28#include <linux/fs.h> 29#include <linux/pagemap.h> 30#include <linux/uts.h> 31#include <linux/wait.h> 32#include <linux/compiler.h> 33#include <asm/uaccess.h> 34#include <linux/slab.h> 35#include <linux/poll.h> 36 37#include <linux/device.h> 38#include <linux/moduleparam.h> 39 40#include <linux/usb_gadgetfs.h> 41#include <linux/usb_gadget.h> 42 43 44/* 45 * The gadgetfs API maps each endpoint to a file descriptor so that you 46 * can use standard synchronous read/write calls for I/O. There's some 47 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode 48 * drivers show how this works in practice. You can also use AIO to 49 * eliminate I/O gaps between requests, to help when streaming data. 50 * 51 * Key parts that must be USB-specific are protocols defining how the 52 * read/write operations relate to the hardware state machines. There 53 * are two types of files. One type is for the device, implementing ep0. 54 * The other type is for each IN or OUT endpoint. In both cases, the 55 * user mode driver must configure the hardware before using it. 56 * 57 * - First, dev_config() is called when /dev/gadget/$CHIP is configured 58 * (by writing configuration and device descriptors). Afterwards it 59 * may serve as a source of device events, used to handle all control 60 * requests other than basic enumeration. 61 * 62 * - Then, after a SET_CONFIGURATION control request, ep_config() is 63 * called when each /dev/gadget/ep* file is configured (by writing 64 * endpoint descriptors). Afterwards these files are used to write() 65 * IN data or to read() OUT data. To halt the endpoint, a "wrong 66 * direction" request is issued (like reading an IN endpoint). 67 * 68 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe 69 * not possible on all hardware. For example, precise fault handling with 70 * respect to data left in endpoint fifos after aborted operations; or 71 * selective clearing of endpoint halts, to implement SET_INTERFACE. 72 */ 73 74#define DRIVER_DESC "USB Gadget filesystem" 75#define DRIVER_VERSION "24 Aug 2004" 76 77static const char driver_desc [] = DRIVER_DESC; 78static const char shortname [] = "gadgetfs"; 79 80MODULE_DESCRIPTION (DRIVER_DESC); 81MODULE_AUTHOR ("David Brownell"); 82MODULE_LICENSE ("GPL"); 83 84 85/*----------------------------------------------------------------------*/ 86 87#define GADGETFS_MAGIC 0xaee71ee7 88#define DMA_ADDR_INVALID (~(dma_addr_t)0) 89 90/* /dev/gadget/$CHIP represents ep0 and the whole device */ 91enum ep0_state { 92 /* DISBLED is the initial state. 93 */ 94 STATE_DEV_DISABLED = 0, 95 96 /* Only one open() of /dev/gadget/$CHIP; only one file tracks 97 * ep0/device i/o modes and binding to the controller. Driver 98 * must always write descriptors to initialize the device, then 99 * the device becomes UNCONNECTED until enumeration. 100 */ 101 STATE_DEV_OPENED, 102 103 /* From then on, ep0 fd is in either of two basic modes: 104 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it 105 * - SETUP: read/write will transfer control data and succeed; 106 * or if "wrong direction", performs protocol stall 107 */ 108 STATE_DEV_UNCONNECTED, 109 STATE_DEV_CONNECTED, 110 STATE_DEV_SETUP, 111 112 /* UNBOUND means the driver closed ep0, so the device won't be 113 * accessible again (DEV_DISABLED) until all fds are closed. 114 */ 115 STATE_DEV_UNBOUND, 116}; 117 118/* enough for the whole queue: most events invalidate others */ 119#define N_EVENT 5 120 121struct dev_data { 122 spinlock_t lock; 123 atomic_t count; 124 enum ep0_state state; /* P: lock */ 125 struct usb_gadgetfs_event event [N_EVENT]; 126 unsigned ev_next; 127 struct fasync_struct *fasync; 128 u8 current_config; 129 130 /* drivers reading ep0 MUST handle control requests (SETUP) 131 * reported that way; else the host will time out. 132 */ 133 unsigned usermode_setup : 1, 134 setup_in : 1, 135 setup_can_stall : 1, 136 setup_out_ready : 1, 137 setup_out_error : 1, 138 setup_abort : 1; 139 unsigned setup_wLength; 140 141 /* the rest is basically write-once */ 142 struct usb_config_descriptor *config, *hs_config; 143 struct usb_device_descriptor *dev; 144 struct usb_request *req; 145 struct usb_gadget *gadget; 146 struct list_head epfiles; 147 void *buf; 148 wait_queue_head_t wait; 149 struct super_block *sb; 150 struct dentry *dentry; 151 152 /* except this scratch i/o buffer for ep0 */ 153 u8 rbuf [256]; 154}; 155 156static inline void get_dev (struct dev_data *data) 157{ 158 atomic_inc (&data->count); 159} 160 161static void put_dev (struct dev_data *data) 162{ 163 if (likely (!atomic_dec_and_test (&data->count))) 164 return; 165 /* needs no more cleanup */ 166 BUG_ON (waitqueue_active (&data->wait)); 167 kfree (data); 168} 169 170static struct dev_data *dev_new (void) 171{ 172 struct dev_data *dev; 173 174 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 175 if (!dev) 176 return NULL; 177 dev->state = STATE_DEV_DISABLED; 178 atomic_set (&dev->count, 1); 179 spin_lock_init (&dev->lock); 180 INIT_LIST_HEAD (&dev->epfiles); 181 init_waitqueue_head (&dev->wait); 182 return dev; 183} 184 185/*----------------------------------------------------------------------*/ 186 187/* other /dev/gadget/$ENDPOINT files represent endpoints */ 188enum ep_state { 189 STATE_EP_DISABLED = 0, 190 STATE_EP_READY, 191 STATE_EP_ENABLED, 192 STATE_EP_UNBOUND, 193}; 194 195struct ep_data { 196 struct semaphore lock; 197 enum ep_state state; 198 atomic_t count; 199 struct dev_data *dev; 200 /* must hold dev->lock before accessing ep or req */ 201 struct usb_ep *ep; 202 struct usb_request *req; 203 ssize_t status; 204 char name [16]; 205 struct usb_endpoint_descriptor desc, hs_desc; 206 struct list_head epfiles; 207 wait_queue_head_t wait; 208 struct dentry *dentry; 209 struct inode *inode; 210}; 211 212static inline void get_ep (struct ep_data *data) 213{ 214 atomic_inc (&data->count); 215} 216 217static void put_ep (struct ep_data *data) 218{ 219 if (likely (!atomic_dec_and_test (&data->count))) 220 return; 221 put_dev (data->dev); 222 /* needs no more cleanup */ 223 BUG_ON (!list_empty (&data->epfiles)); 224 BUG_ON (waitqueue_active (&data->wait)); 225 kfree (data); 226} 227 228/*----------------------------------------------------------------------*/ 229 230/* most "how to use the hardware" policy choices are in userspace: 231 * mapping endpoint roles (which the driver needs) to the capabilities 232 * which the usb controller has. most of those capabilities are exposed 233 * implicitly, starting with the driver name and then endpoint names. 234 */ 235 236static const char *CHIP; 237 238/*----------------------------------------------------------------------*/ 239 240/* NOTE: don't use dev_printk calls before binding to the gadget 241 * at the end of ep0 configuration, or after unbind. 242 */ 243 244/* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */ 245#define xprintk(d,level,fmt,args...) \ 246 printk(level "%s: " fmt , shortname , ## args) 247 248#ifdef DEBUG 249#define DBG(dev,fmt,args...) \ 250 xprintk(dev , KERN_DEBUG , fmt , ## args) 251#else 252#define DBG(dev,fmt,args...) \ 253 do { } while (0) 254#endif /* DEBUG */ 255 256#ifdef VERBOSE 257#define VDEBUG DBG 258#else 259#define VDEBUG(dev,fmt,args...) \ 260 do { } while (0) 261#endif /* DEBUG */ 262 263#define ERROR(dev,fmt,args...) \ 264 xprintk(dev , KERN_ERR , fmt , ## args) 265#define WARN(dev,fmt,args...) \ 266 xprintk(dev , KERN_WARNING , fmt , ## args) 267#define INFO(dev,fmt,args...) \ 268 xprintk(dev , KERN_INFO , fmt , ## args) 269 270 271/*----------------------------------------------------------------------*/ 272 273/* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso) 274 * 275 * After opening, configure non-control endpoints. Then use normal 276 * stream read() and write() requests; and maybe ioctl() to get more 277 * precise FIFO status when recovering from cancellation. 278 */ 279 280static void epio_complete (struct usb_ep *ep, struct usb_request *req) 281{ 282 struct ep_data *epdata = ep->driver_data; 283 284 if (!req->context) 285 return; 286 if (req->status) 287 epdata->status = req->status; 288 else 289 epdata->status = req->actual; 290 complete ((struct completion *)req->context); 291} 292 293/* tasklock endpoint, returning when it's connected. 294 * still need dev->lock to use epdata->ep. 295 */ 296static int 297get_ready_ep (unsigned f_flags, struct ep_data *epdata) 298{ 299 int val; 300 301 if (f_flags & O_NONBLOCK) { 302 if (down_trylock (&epdata->lock) != 0) 303 goto nonblock; 304 if (epdata->state != STATE_EP_ENABLED) { 305 up (&epdata->lock); 306nonblock: 307 val = -EAGAIN; 308 } else 309 val = 0; 310 return val; 311 } 312 313 if ((val = down_interruptible (&epdata->lock)) < 0) 314 return val; 315 316 switch (epdata->state) { 317 case STATE_EP_ENABLED: 318 break; 319 // case STATE_EP_DISABLED: /* "can't happen" */ 320 // case STATE_EP_READY: /* "can't happen" */ 321 default: /* error! */ 322 pr_debug ("%s: ep %p not available, state %d\n", 323 shortname, epdata, epdata->state); 324 // FALLTHROUGH 325 case STATE_EP_UNBOUND: /* clean disconnect */ 326 val = -ENODEV; 327 up (&epdata->lock); 328 } 329 return val; 330} 331 332static ssize_t 333ep_io (struct ep_data *epdata, void *buf, unsigned len) 334{ 335 DECLARE_COMPLETION_ONSTACK (done); 336 int value; 337 338 spin_lock_irq (&epdata->dev->lock); 339 if (likely (epdata->ep != NULL)) { 340 struct usb_request *req = epdata->req; 341 342 req->context = &done; 343 req->complete = epio_complete; 344 req->buf = buf; 345 req->length = len; 346 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC); 347 } else 348 value = -ENODEV; 349 spin_unlock_irq (&epdata->dev->lock); 350 351 if (likely (value == 0)) { 352 value = wait_event_interruptible (done.wait, done.done); 353 if (value != 0) { 354 spin_lock_irq (&epdata->dev->lock); 355 if (likely (epdata->ep != NULL)) { 356 DBG (epdata->dev, "%s i/o interrupted\n", 357 epdata->name); 358 usb_ep_dequeue (epdata->ep, epdata->req); 359 spin_unlock_irq (&epdata->dev->lock); 360 361 wait_event (done.wait, done.done); 362 if (epdata->status == -ECONNRESET) 363 epdata->status = -EINTR; 364 } else { 365 spin_unlock_irq (&epdata->dev->lock); 366 367 DBG (epdata->dev, "endpoint gone\n"); 368 epdata->status = -ENODEV; 369 } 370 } 371 return epdata->status; 372 } 373 return value; 374} 375 376 377/* handle a synchronous OUT bulk/intr/iso transfer */ 378static ssize_t 379ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) 380{ 381 struct ep_data *data = fd->private_data; 382 void *kbuf; 383 ssize_t value; 384 385 if ((value = get_ready_ep (fd->f_flags, data)) < 0) 386 return value; 387 388 /* halt any endpoint by doing a "wrong direction" i/o call */ 389 if (data->desc.bEndpointAddress & USB_DIR_IN) { 390 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) 391 == USB_ENDPOINT_XFER_ISOC) 392 return -EINVAL; 393 DBG (data->dev, "%s halt\n", data->name); 394 spin_lock_irq (&data->dev->lock); 395 if (likely (data->ep != NULL)) 396 usb_ep_set_halt (data->ep); 397 spin_unlock_irq (&data->dev->lock); 398 up (&data->lock); 399 return -EBADMSG; 400 } 401 402 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */ 403 404 value = -ENOMEM; 405 kbuf = kmalloc (len, GFP_KERNEL); 406 if (unlikely (!kbuf)) 407 goto free1; 408 409 value = ep_io (data, kbuf, len); 410 VDEBUG (data->dev, "%s read %zu OUT, status %d\n", 411 data->name, len, (int) value); 412 if (value >= 0 && copy_to_user (buf, kbuf, value)) 413 value = -EFAULT; 414 415free1: 416 up (&data->lock); 417 kfree (kbuf); 418 return value; 419} 420 421/* handle a synchronous IN bulk/intr/iso transfer */ 422static ssize_t 423ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 424{ 425 struct ep_data *data = fd->private_data; 426 void *kbuf; 427 ssize_t value; 428 429 if ((value = get_ready_ep (fd->f_flags, data)) < 0) 430 return value; 431 432 /* halt any endpoint by doing a "wrong direction" i/o call */ 433 if (!(data->desc.bEndpointAddress & USB_DIR_IN)) { 434 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) 435 == USB_ENDPOINT_XFER_ISOC) 436 return -EINVAL; 437 DBG (data->dev, "%s halt\n", data->name); 438 spin_lock_irq (&data->dev->lock); 439 if (likely (data->ep != NULL)) 440 usb_ep_set_halt (data->ep); 441 spin_unlock_irq (&data->dev->lock); 442 up (&data->lock); 443 return -EBADMSG; 444 } 445 446 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */ 447 448 value = -ENOMEM; 449 kbuf = kmalloc (len, GFP_KERNEL); 450 if (!kbuf) 451 goto free1; 452 if (copy_from_user (kbuf, buf, len)) { 453 value = -EFAULT; 454 goto free1; 455 } 456 457 value = ep_io (data, kbuf, len); 458 VDEBUG (data->dev, "%s write %zu IN, status %d\n", 459 data->name, len, (int) value); 460free1: 461 up (&data->lock); 462 kfree (kbuf); 463 return value; 464} 465 466static int 467ep_release (struct inode *inode, struct file *fd) 468{ 469 struct ep_data *data = fd->private_data; 470 int value; 471 472 if ((value = down_interruptible(&data->lock)) < 0) 473 return value; 474 475 /* clean up if this can be reopened */ 476 if (data->state != STATE_EP_UNBOUND) { 477 data->state = STATE_EP_DISABLED; 478 data->desc.bDescriptorType = 0; 479 data->hs_desc.bDescriptorType = 0; 480 usb_ep_disable(data->ep); 481 } 482 up (&data->lock); 483 put_ep (data); 484 return 0; 485} 486 487static int ep_ioctl (struct inode *inode, struct file *fd, 488 unsigned code, unsigned long value) 489{ 490 struct ep_data *data = fd->private_data; 491 int status; 492 493 if ((status = get_ready_ep (fd->f_flags, data)) < 0) 494 return status; 495 496 spin_lock_irq (&data->dev->lock); 497 if (likely (data->ep != NULL)) { 498 switch (code) { 499 case GADGETFS_FIFO_STATUS: 500 status = usb_ep_fifo_status (data->ep); 501 break; 502 case GADGETFS_FIFO_FLUSH: 503 usb_ep_fifo_flush (data->ep); 504 break; 505 case GADGETFS_CLEAR_HALT: 506 status = usb_ep_clear_halt (data->ep); 507 break; 508 default: 509 status = -ENOTTY; 510 } 511 } else 512 status = -ENODEV; 513 spin_unlock_irq (&data->dev->lock); 514 up (&data->lock); 515 return status; 516} 517 518/*----------------------------------------------------------------------*/ 519 520/* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */ 521 522struct kiocb_priv { 523 struct usb_request *req; 524 struct ep_data *epdata; 525 void *buf; 526 const struct iovec *iv; 527 unsigned long nr_segs; 528 unsigned actual; 529}; 530 531static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e) 532{ 533 struct kiocb_priv *priv = iocb->private; 534 struct ep_data *epdata; 535 int value; 536 537 local_irq_disable(); 538 epdata = priv->epdata; 539 // spin_lock(&epdata->dev->lock); 540 kiocbSetCancelled(iocb); 541 if (likely(epdata && epdata->ep && priv->req)) 542 value = usb_ep_dequeue (epdata->ep, priv->req); 543 else 544 value = -EINVAL; 545 // spin_unlock(&epdata->dev->lock); 546 local_irq_enable(); 547 548 aio_put_req(iocb); 549 return value; 550} 551 552static ssize_t ep_aio_read_retry(struct kiocb *iocb) 553{ 554 struct kiocb_priv *priv = iocb->private; 555 ssize_t len, total; 556 int i; 557 558 /* we "retry" to get the right mm context for this: */ 559 560 /* copy stuff into user buffers */ 561 total = priv->actual; 562 len = 0; 563 for (i=0; i < priv->nr_segs; i++) { 564 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total); 565 566 if (copy_to_user(priv->iv[i].iov_base, priv->buf, this)) { 567 if (len == 0) 568 len = -EFAULT; 569 break; 570 } 571 572 total -= this; 573 len += this; 574 if (total == 0) 575 break; 576 } 577 kfree(priv->buf); 578 kfree(priv); 579 aio_put_req(iocb); 580 return len; 581} 582 583static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req) 584{ 585 struct kiocb *iocb = req->context; 586 struct kiocb_priv *priv = iocb->private; 587 struct ep_data *epdata = priv->epdata; 588 589 /* lock against disconnect (and ideally, cancel) */ 590 spin_lock(&epdata->dev->lock); 591 priv->req = NULL; 592 priv->epdata = NULL; 593 if (priv->iv == NULL 594 || unlikely(req->actual == 0) 595 || unlikely(kiocbIsCancelled(iocb))) { 596 kfree(req->buf); 597 kfree(priv); 598 iocb->private = NULL; 599 /* aio_complete() reports bytes-transferred _and_ faults */ 600 if (unlikely(kiocbIsCancelled(iocb))) 601 aio_put_req(iocb); 602 else 603 aio_complete(iocb, 604 req->actual ? req->actual : req->status, 605 req->status); 606 } else { 607 /* retry() won't report both; so we hide some faults */ 608 if (unlikely(0 != req->status)) 609 DBG(epdata->dev, "%s fault %d len %d\n", 610 ep->name, req->status, req->actual); 611 612 priv->buf = req->buf; 613 priv->actual = req->actual; 614 kick_iocb(iocb); 615 } 616 spin_unlock(&epdata->dev->lock); 617 618 usb_ep_free_request(ep, req); 619 put_ep(epdata); 620} 621 622static ssize_t 623ep_aio_rwtail( 624 struct kiocb *iocb, 625 char *buf, 626 size_t len, 627 struct ep_data *epdata, 628 const struct iovec *iv, 629 unsigned long nr_segs 630) 631{ 632 struct kiocb_priv *priv; 633 struct usb_request *req; 634 ssize_t value; 635 636 priv = kmalloc(sizeof *priv, GFP_KERNEL); 637 if (!priv) { 638 value = -ENOMEM; 639fail: 640 kfree(buf); 641 return value; 642 } 643 iocb->private = priv; 644 priv->iv = iv; 645 priv->nr_segs = nr_segs; 646 647 value = get_ready_ep(iocb->ki_filp->f_flags, epdata); 648 if (unlikely(value < 0)) { 649 kfree(priv); 650 goto fail; 651 } 652 653 iocb->ki_cancel = ep_aio_cancel; 654 get_ep(epdata); 655 priv->epdata = epdata; 656 priv->actual = 0; 657 658 /* each kiocb is coupled to one usb_request, but we can't 659 * allocate or submit those if the host disconnected. 660 */ 661 spin_lock_irq(&epdata->dev->lock); 662 if (likely(epdata->ep)) { 663 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC); 664 if (likely(req)) { 665 priv->req = req; 666 req->buf = buf; 667 req->length = len; 668 req->complete = ep_aio_complete; 669 req->context = iocb; 670 value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC); 671 if (unlikely(0 != value)) 672 usb_ep_free_request(epdata->ep, req); 673 } else 674 value = -EAGAIN; 675 } else 676 value = -ENODEV; 677 spin_unlock_irq(&epdata->dev->lock); 678 679 up(&epdata->lock); 680 681 if (unlikely(value)) { 682 kfree(priv); 683 put_ep(epdata); 684 } else 685 value = (iv ? -EIOCBRETRY : -EIOCBQUEUED); 686 return value; 687} 688 689static ssize_t 690ep_aio_read(struct kiocb *iocb, const struct iovec *iov, 691 unsigned long nr_segs, loff_t o) 692{ 693 struct ep_data *epdata = iocb->ki_filp->private_data; 694 char *buf; 695 696 if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN)) 697 return -EINVAL; 698 699 buf = kmalloc(iocb->ki_left, GFP_KERNEL); 700 if (unlikely(!buf)) 701 return -ENOMEM; 702 703 iocb->ki_retry = ep_aio_read_retry; 704 return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs); 705} 706 707static ssize_t 708ep_aio_write(struct kiocb *iocb, const struct iovec *iov, 709 unsigned long nr_segs, loff_t o) 710{ 711 struct ep_data *epdata = iocb->ki_filp->private_data; 712 char *buf; 713 size_t len = 0; 714 int i = 0; 715 716 if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN))) 717 return -EINVAL; 718 719 buf = kmalloc(iocb->ki_left, GFP_KERNEL); 720 if (unlikely(!buf)) 721 return -ENOMEM; 722 723 for (i=0; i < nr_segs; i++) { 724 if (unlikely(copy_from_user(&buf[len], iov[i].iov_base, 725 iov[i].iov_len) != 0)) { 726 kfree(buf); 727 return -EFAULT; 728 } 729 len += iov[i].iov_len; 730 } 731 return ep_aio_rwtail(iocb, buf, len, epdata, NULL, 0); 732} 733 734/*----------------------------------------------------------------------*/ 735 736/* used after endpoint configuration */ 737static const struct file_operations ep_io_operations = { 738 .owner = THIS_MODULE, 739 .llseek = no_llseek, 740 741 .read = ep_read, 742 .write = ep_write, 743 .ioctl = ep_ioctl, 744 .release = ep_release, 745 746 .aio_read = ep_aio_read, 747 .aio_write = ep_aio_write, 748}; 749 750/* ENDPOINT INITIALIZATION 751 * 752 * fd = open ("/dev/gadget/$ENDPOINT", O_RDWR) 753 * status = write (fd, descriptors, sizeof descriptors) 754 * 755 * That write establishes the endpoint configuration, configuring 756 * the controller to process bulk, interrupt, or isochronous transfers 757 * at the right maxpacket size, and so on. 758 * 759 * The descriptors are message type 1, identified by a host order u32 760 * at the beginning of what's written. Descriptor order is: full/low 761 * speed descriptor, then optional high speed descriptor. 762 */ 763static ssize_t 764ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 765{ 766 struct ep_data *data = fd->private_data; 767 struct usb_ep *ep; 768 u32 tag; 769 int value, length = len; 770 771 if ((value = down_interruptible (&data->lock)) < 0) 772 return value; 773 774 if (data->state != STATE_EP_READY) { 775 value = -EL2HLT; 776 goto fail; 777 } 778 779 value = len; 780 if (len < USB_DT_ENDPOINT_SIZE + 4) 781 goto fail0; 782 783 /* we might need to change message format someday */ 784 if (copy_from_user (&tag, buf, 4)) { 785 goto fail1; 786 } 787 if (tag != 1) { 788 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag); 789 goto fail0; 790 } 791 buf += 4; 792 len -= 4; 793 794 /* NOTE: audio endpoint extensions not accepted here; 795 * just don't include the extra bytes. 796 */ 797 798 /* full/low speed descriptor, then high speed */ 799 if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) { 800 goto fail1; 801 } 802 if (data->desc.bLength != USB_DT_ENDPOINT_SIZE 803 || data->desc.bDescriptorType != USB_DT_ENDPOINT) 804 goto fail0; 805 if (len != USB_DT_ENDPOINT_SIZE) { 806 if (len != 2 * USB_DT_ENDPOINT_SIZE) 807 goto fail0; 808 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE, 809 USB_DT_ENDPOINT_SIZE)) { 810 goto fail1; 811 } 812 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE 813 || data->hs_desc.bDescriptorType 814 != USB_DT_ENDPOINT) { 815 DBG(data->dev, "config %s, bad hs length or type\n", 816 data->name); 817 goto fail0; 818 } 819 } 820 821 spin_lock_irq (&data->dev->lock); 822 if (data->dev->state == STATE_DEV_UNBOUND) { 823 value = -ENOENT; 824 goto gone; 825 } else if ((ep = data->ep) == NULL) { 826 value = -ENODEV; 827 goto gone; 828 } 829 switch (data->dev->gadget->speed) { 830 case USB_SPEED_LOW: 831 case USB_SPEED_FULL: 832 value = usb_ep_enable (ep, &data->desc); 833 if (value == 0) 834 data->state = STATE_EP_ENABLED; 835 break; 836#ifdef CONFIG_USB_GADGET_DUALSPEED 837 case USB_SPEED_HIGH: 838 /* fails if caller didn't provide that descriptor... */ 839 value = usb_ep_enable (ep, &data->hs_desc); 840 if (value == 0) 841 data->state = STATE_EP_ENABLED; 842 break; 843#endif 844 default: 845 DBG(data->dev, "unconnected, %s init abandoned\n", 846 data->name); 847 value = -EINVAL; 848 } 849 if (value == 0) { 850 fd->f_op = &ep_io_operations; 851 value = length; 852 } 853gone: 854 spin_unlock_irq (&data->dev->lock); 855 if (value < 0) { 856fail: 857 data->desc.bDescriptorType = 0; 858 data->hs_desc.bDescriptorType = 0; 859 } 860 up (&data->lock); 861 return value; 862fail0: 863 value = -EINVAL; 864 goto fail; 865fail1: 866 value = -EFAULT; 867 goto fail; 868} 869 870static int 871ep_open (struct inode *inode, struct file *fd) 872{ 873 struct ep_data *data = inode->i_private; 874 int value = -EBUSY; 875 876 if (down_interruptible (&data->lock) != 0) 877 return -EINTR; 878 spin_lock_irq (&data->dev->lock); 879 if (data->dev->state == STATE_DEV_UNBOUND) 880 value = -ENOENT; 881 else if (data->state == STATE_EP_DISABLED) { 882 value = 0; 883 data->state = STATE_EP_READY; 884 get_ep (data); 885 fd->private_data = data; 886 VDEBUG (data->dev, "%s ready\n", data->name); 887 } else 888 DBG (data->dev, "%s state %d\n", 889 data->name, data->state); 890 spin_unlock_irq (&data->dev->lock); 891 up (&data->lock); 892 return value; 893} 894 895/* used before endpoint configuration */ 896static const struct file_operations ep_config_operations = { 897 .owner = THIS_MODULE, 898 .llseek = no_llseek, 899 900 .open = ep_open, 901 .write = ep_config, 902 .release = ep_release, 903}; 904 905/*----------------------------------------------------------------------*/ 906 907/* EP0 IMPLEMENTATION can be partly in userspace. 908 * 909 * Drivers that use this facility receive various events, including 910 * control requests the kernel doesn't handle. Drivers that don't 911 * use this facility may be too simple-minded for real applications. 912 */ 913 914static inline void ep0_readable (struct dev_data *dev) 915{ 916 wake_up (&dev->wait); 917 kill_fasync (&dev->fasync, SIGIO, POLL_IN); 918} 919 920static void clean_req (struct usb_ep *ep, struct usb_request *req) 921{ 922 struct dev_data *dev = ep->driver_data; 923 924 if (req->buf != dev->rbuf) { 925 usb_ep_free_buffer (ep, req->buf, req->dma, req->length); 926 req->buf = dev->rbuf; 927 req->dma = DMA_ADDR_INVALID; 928 } 929 req->complete = epio_complete; 930 dev->setup_out_ready = 0; 931} 932 933static void ep0_complete (struct usb_ep *ep, struct usb_request *req) 934{ 935 struct dev_data *dev = ep->driver_data; 936 int free = 1; 937 938 /* for control OUT, data must still get to userspace */ 939 if (!dev->setup_in) { 940 dev->setup_out_error = (req->status != 0); 941 if (!dev->setup_out_error) 942 free = 0; 943 dev->setup_out_ready = 1; 944 ep0_readable (dev); 945 } else { 946 unsigned long flags; 947 948 spin_lock_irqsave(&dev->lock, flags); 949 if (dev->state == STATE_DEV_SETUP) 950 dev->state = STATE_DEV_CONNECTED; 951 spin_unlock_irqrestore(&dev->lock, flags); 952 } 953 954 /* clean up as appropriate */ 955 if (free && req->buf != &dev->rbuf) 956 clean_req (ep, req); 957 req->complete = epio_complete; 958} 959 960static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len) 961{ 962 struct dev_data *dev = ep->driver_data; 963 964 if (dev->setup_out_ready) { 965 DBG (dev, "ep0 request busy!\n"); 966 return -EBUSY; 967 } 968 if (len > sizeof (dev->rbuf)) 969 req->buf = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC); 970 if (req->buf == 0) { 971 req->buf = dev->rbuf; 972 return -ENOMEM; 973 } 974 req->complete = ep0_complete; 975 req->length = len; 976 req->zero = 0; 977 return 0; 978} 979 980static ssize_t 981ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) 982{ 983 struct dev_data *dev = fd->private_data; 984 ssize_t retval; 985 enum ep0_state state; 986 987 spin_lock_irq (&dev->lock); 988 989 /* report fd mode change before acting on it */ 990 if (dev->setup_abort) { 991 dev->setup_abort = 0; 992 retval = -EIDRM; 993 goto done; 994 } 995 996 /* control DATA stage */ 997 if ((state = dev->state) == STATE_DEV_SETUP) { 998 999 if (dev->setup_in) { /* stall IN */ 1000 VDEBUG(dev, "ep0in stall\n"); 1001 (void) usb_ep_set_halt (dev->gadget->ep0); 1002 retval = -EL2HLT; 1003 dev->state = STATE_DEV_CONNECTED; 1004 1005 } else if (len == 0) { /* ack SET_CONFIGURATION etc */ 1006 struct usb_ep *ep = dev->gadget->ep0; 1007 struct usb_request *req = dev->req; 1008 1009 if ((retval = setup_req (ep, req, 0)) == 0) 1010 retval = usb_ep_queue (ep, req, GFP_ATOMIC); 1011 dev->state = STATE_DEV_CONNECTED; 1012 1013 /* assume that was SET_CONFIGURATION */ 1014 if (dev->current_config) { 1015 unsigned power; 1016#ifdef CONFIG_USB_GADGET_DUALSPEED 1017 if (dev->gadget->speed == USB_SPEED_HIGH) 1018 power = dev->hs_config->bMaxPower; 1019 else 1020#endif 1021 power = dev->config->bMaxPower; 1022 usb_gadget_vbus_draw(dev->gadget, 2 * power); 1023 } 1024 1025 } else { /* collect OUT data */ 1026 if ((fd->f_flags & O_NONBLOCK) != 0 1027 && !dev->setup_out_ready) { 1028 retval = -EAGAIN; 1029 goto done; 1030 } 1031 spin_unlock_irq (&dev->lock); 1032 retval = wait_event_interruptible (dev->wait, 1033 dev->setup_out_ready != 0); 1034 1035 /* FIXME state could change from under us */ 1036 spin_lock_irq (&dev->lock); 1037 if (retval) 1038 goto done; 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 int tmp = dev->ev_next; 1066 1067 len = min (len, tmp * sizeof (struct usb_gadgetfs_event)); 1068 n = len / sizeof (struct usb_gadgetfs_event); 1069 1070 /* ep0 can't deliver events when STATE_DEV_SETUP */ 1071 for (i = 0; i < n; i++) { 1072 if (dev->event [i].type == GADGETFS_SETUP) { 1073 len = i + 1; 1074 len *= sizeof (struct usb_gadgetfs_event); 1075 n = 0; 1076 break; 1077 } 1078 } 1079 spin_unlock_irq (&dev->lock); 1080 if (copy_to_user (buf, &dev->event, len)) 1081 retval = -EFAULT; 1082 else 1083 retval = len; 1084 if (len > 0) { 1085 len /= sizeof (struct usb_gadgetfs_event); 1086 1087 /* NOTE this doesn't guard against broken drivers; 1088 * concurrent ep0 readers may lose events. 1089 */ 1090 spin_lock_irq (&dev->lock); 1091 dev->ev_next -= len; 1092 if (dev->ev_next != 0) 1093 memmove (&dev->event, &dev->event [len], 1094 sizeof (struct usb_gadgetfs_event) 1095 * (tmp - len)); 1096 if (n == 0) 1097 dev->state = STATE_DEV_SETUP; 1098 spin_unlock_irq (&dev->lock); 1099 } 1100 return retval; 1101 } 1102 if (fd->f_flags & O_NONBLOCK) { 1103 retval = -EAGAIN; 1104 goto done; 1105 } 1106 1107 switch (state) { 1108 default: 1109 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state); 1110 retval = -ESRCH; 1111 break; 1112 case STATE_DEV_UNCONNECTED: 1113 case STATE_DEV_CONNECTED: 1114 spin_unlock_irq (&dev->lock); 1115 DBG (dev, "%s wait\n", __FUNCTION__); 1116 1117 /* wait for events */ 1118 retval = wait_event_interruptible (dev->wait, 1119 dev->ev_next != 0); 1120 if (retval < 0) 1121 return retval; 1122 spin_lock_irq (&dev->lock); 1123 goto scan; 1124 } 1125 1126done: 1127 spin_unlock_irq (&dev->lock); 1128 return retval; 1129} 1130 1131static struct usb_gadgetfs_event * 1132next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type) 1133{ 1134 struct usb_gadgetfs_event *event; 1135 unsigned i; 1136 1137 switch (type) { 1138 /* these events purge the queue */ 1139 case GADGETFS_DISCONNECT: 1140 if (dev->state == STATE_DEV_SETUP) 1141 dev->setup_abort = 1; 1142 // FALL THROUGH 1143 case GADGETFS_CONNECT: 1144 dev->ev_next = 0; 1145 break; 1146 case GADGETFS_SETUP: /* previous request timed out */ 1147 case GADGETFS_SUSPEND: /* same effect */ 1148 /* these events can't be repeated */ 1149 for (i = 0; i != dev->ev_next; i++) { 1150 if (dev->event [i].type != type) 1151 continue; 1152 DBG (dev, "discard old event %d\n", type); 1153 dev->ev_next--; 1154 if (i == dev->ev_next) 1155 break; 1156 /* indices start at zero, for simplicity */ 1157 memmove (&dev->event [i], &dev->event [i + 1], 1158 sizeof (struct usb_gadgetfs_event) 1159 * (dev->ev_next - i)); 1160 } 1161 break; 1162 default: 1163 BUG (); 1164 } 1165 event = &dev->event [dev->ev_next++]; 1166 BUG_ON (dev->ev_next > N_EVENT); 1167 VDEBUG (dev, "ev %d, next %d\n", type, dev->ev_next); 1168 memset (event, 0, sizeof *event); 1169 event->type = type; 1170 return event; 1171} 1172 1173static ssize_t 1174ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 1175{ 1176 struct dev_data *dev = fd->private_data; 1177 ssize_t retval = -ESRCH; 1178 1179 spin_lock_irq (&dev->lock); 1180 1181 /* report fd mode change before acting on it */ 1182 if (dev->setup_abort) { 1183 dev->setup_abort = 0; 1184 retval = -EIDRM; 1185 1186 /* data and/or status stage for control request */ 1187 } else if (dev->state == STATE_DEV_SETUP) { 1188 1189 /* IN DATA+STATUS caller makes len <= wLength */ 1190 if (dev->setup_in) { 1191 retval = setup_req (dev->gadget->ep0, dev->req, len); 1192 if (retval == 0) { 1193 spin_unlock_irq (&dev->lock); 1194 if (copy_from_user (dev->req->buf, buf, len)) 1195 retval = -EFAULT; 1196 else { 1197 if (len < dev->setup_wLength) 1198 dev->req->zero = 1; 1199 retval = usb_ep_queue ( 1200 dev->gadget->ep0, dev->req, 1201 GFP_KERNEL); 1202 } 1203 if (retval < 0) { 1204 spin_lock_irq (&dev->lock); 1205 clean_req (dev->gadget->ep0, dev->req); 1206 spin_unlock_irq (&dev->lock); 1207 } else 1208 retval = len; 1209 1210 return retval; 1211 } 1212 1213 /* can stall some OUT transfers */ 1214 } else if (dev->setup_can_stall) { 1215 VDEBUG(dev, "ep0out stall\n"); 1216 (void) usb_ep_set_halt (dev->gadget->ep0); 1217 retval = -EL2HLT; 1218 dev->state = STATE_DEV_CONNECTED; 1219 } else { 1220 DBG(dev, "bogus ep0out stall!\n"); 1221 } 1222 } else 1223 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state); 1224 1225 spin_unlock_irq (&dev->lock); 1226 return retval; 1227} 1228 1229static int 1230ep0_fasync (int f, struct file *fd, int on) 1231{ 1232 struct dev_data *dev = fd->private_data; 1233 // caller must F_SETOWN before signal delivery happens 1234 VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off"); 1235 return fasync_helper (f, fd, on, &dev->fasync); 1236} 1237 1238static struct usb_gadget_driver gadgetfs_driver; 1239 1240static int 1241dev_release (struct inode *inode, struct file *fd) 1242{ 1243 struct dev_data *dev = fd->private_data; 1244 1245 /* closing ep0 === shutdown all */ 1246 1247 usb_gadget_unregister_driver (&gadgetfs_driver); 1248 1249 /* at this point "good" hardware has disconnected the 1250 * device from USB; the host won't see it any more. 1251 * alternatively, all host requests will time out. 1252 */ 1253 1254 fasync_helper (-1, fd, 0, &dev->fasync); 1255 kfree (dev->buf); 1256 dev->buf = NULL; 1257 put_dev (dev); 1258 1259 /* other endpoints were all decoupled from this device */ 1260 spin_lock_irq(&dev->lock); 1261 dev->state = STATE_DEV_DISABLED; 1262 spin_unlock_irq(&dev->lock); 1263 return 0; 1264} 1265 1266static unsigned int 1267ep0_poll (struct file *fd, poll_table *wait) 1268{ 1269 struct dev_data *dev = fd->private_data; 1270 int mask = 0; 1271 1272 poll_wait(fd, &dev->wait, wait); 1273 1274 spin_lock_irq (&dev->lock); 1275 1276 /* report fd mode change before acting on it */ 1277 if (dev->setup_abort) { 1278 dev->setup_abort = 0; 1279 mask = POLLHUP; 1280 goto out; 1281 } 1282 1283 if (dev->state == STATE_DEV_SETUP) { 1284 if (dev->setup_in || dev->setup_can_stall) 1285 mask = POLLOUT; 1286 } else { 1287 if (dev->ev_next != 0) 1288 mask = POLLIN; 1289 } 1290out: 1291 spin_unlock_irq(&dev->lock); 1292 return mask; 1293} 1294 1295static int dev_ioctl (struct inode *inode, struct file *fd, 1296 unsigned code, unsigned long value) 1297{ 1298 struct dev_data *dev = fd->private_data; 1299 struct usb_gadget *gadget = dev->gadget; 1300 1301 if (gadget->ops->ioctl) 1302 return gadget->ops->ioctl (gadget, code, value); 1303 return -ENOTTY; 1304} 1305 1306/* used after device configuration */ 1307static const struct file_operations ep0_io_operations = { 1308 .owner = THIS_MODULE, 1309 .llseek = no_llseek, 1310 1311 .read = ep0_read, 1312 .write = ep0_write, 1313 .fasync = ep0_fasync, 1314 .poll = ep0_poll, 1315 .ioctl = dev_ioctl, 1316 .release = dev_release, 1317}; 1318 1319/*----------------------------------------------------------------------*/ 1320 1321/* The in-kernel gadget driver handles most ep0 issues, in particular 1322 * enumerating the single configuration (as provided from user space). 1323 * 1324 * Unrecognized ep0 requests may be handled in user space. 1325 */ 1326 1327#ifdef CONFIG_USB_GADGET_DUALSPEED 1328static void make_qualifier (struct dev_data *dev) 1329{ 1330 struct usb_qualifier_descriptor qual; 1331 struct usb_device_descriptor *desc; 1332 1333 qual.bLength = sizeof qual; 1334 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER; 1335 qual.bcdUSB = __constant_cpu_to_le16 (0x0200); 1336 1337 desc = dev->dev; 1338 qual.bDeviceClass = desc->bDeviceClass; 1339 qual.bDeviceSubClass = desc->bDeviceSubClass; 1340 qual.bDeviceProtocol = desc->bDeviceProtocol; 1341 1342 /* assumes ep0 uses the same value for both speeds ... */ 1343 qual.bMaxPacketSize0 = desc->bMaxPacketSize0; 1344 1345 qual.bNumConfigurations = 1; 1346 qual.bRESERVED = 0; 1347 1348 memcpy (dev->rbuf, &qual, sizeof qual); 1349} 1350#endif 1351 1352static int 1353config_buf (struct dev_data *dev, u8 type, unsigned index) 1354{ 1355 int len; 1356#ifdef CONFIG_USB_GADGET_DUALSPEED 1357 int hs; 1358#endif 1359 1360 /* only one configuration */ 1361 if (index > 0) 1362 return -EINVAL; 1363 1364#ifdef CONFIG_USB_GADGET_DUALSPEED 1365 hs = (dev->gadget->speed == USB_SPEED_HIGH); 1366 if (type == USB_DT_OTHER_SPEED_CONFIG) 1367 hs = !hs; 1368 if (hs) { 1369 dev->req->buf = dev->hs_config; 1370 len = le16_to_cpup (&dev->hs_config->wTotalLength); 1371 } else 1372#endif 1373 { 1374 dev->req->buf = dev->config; 1375 len = le16_to_cpup (&dev->config->wTotalLength); 1376 } 1377 ((u8 *)dev->req->buf) [1] = type; 1378 return len; 1379} 1380 1381static int 1382gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) 1383{ 1384 struct dev_data *dev = get_gadget_data (gadget); 1385 struct usb_request *req = dev->req; 1386 int value = -EOPNOTSUPP; 1387 struct usb_gadgetfs_event *event; 1388 u16 w_value = le16_to_cpu(ctrl->wValue); 1389 u16 w_length = le16_to_cpu(ctrl->wLength); 1390 1391 spin_lock (&dev->lock); 1392 dev->setup_abort = 0; 1393 if (dev->state == STATE_DEV_UNCONNECTED) { 1394 1395 dev->state = STATE_DEV_CONNECTED; 1396 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket; 1397 1398#ifdef CONFIG_USB_GADGET_DUALSPEED 1399 if (gadget->speed == USB_SPEED_HIGH && dev->hs_config == 0) { 1400 ERROR (dev, "no high speed config??\n"); 1401 return -EINVAL; 1402 } 1403#endif /* CONFIG_USB_GADGET_DUALSPEED */ 1404 1405 INFO (dev, "connected\n"); 1406 event = next_event (dev, GADGETFS_CONNECT); 1407 event->u.speed = gadget->speed; 1408 ep0_readable (dev); 1409 1410 /* host may have given up waiting for response. we can miss control 1411 * requests handled lower down (device/endpoint status and features); 1412 * then ep0_{read,write} will report the wrong status. controller 1413 * driver will have aborted pending i/o. 1414 */ 1415 } else if (dev->state == STATE_DEV_SETUP) 1416 dev->setup_abort = 1; 1417 1418 req->buf = dev->rbuf; 1419 req->dma = DMA_ADDR_INVALID; 1420 req->context = NULL; 1421 value = -EOPNOTSUPP; 1422 switch (ctrl->bRequest) { 1423 1424 case USB_REQ_GET_DESCRIPTOR: 1425 if (ctrl->bRequestType != USB_DIR_IN) 1426 goto unrecognized; 1427 switch (w_value >> 8) { 1428 1429 case USB_DT_DEVICE: 1430 value = min (w_length, (u16) sizeof *dev->dev); 1431 req->buf = dev->dev; 1432 break; 1433#ifdef CONFIG_USB_GADGET_DUALSPEED 1434 case USB_DT_DEVICE_QUALIFIER: 1435 if (!dev->hs_config) 1436 break; 1437 value = min (w_length, (u16) 1438 sizeof (struct usb_qualifier_descriptor)); 1439 make_qualifier (dev); 1440 break; 1441 case USB_DT_OTHER_SPEED_CONFIG: 1442 // FALLTHROUGH 1443#endif 1444 case USB_DT_CONFIG: 1445 value = config_buf (dev, 1446 w_value >> 8, 1447 w_value & 0xff); 1448 if (value >= 0) 1449 value = min (w_length, (u16) value); 1450 break; 1451 case USB_DT_STRING: 1452 goto unrecognized; 1453 1454 default: // all others are errors 1455 break; 1456 } 1457 break; 1458 1459 /* currently one config, two speeds */ 1460 case USB_REQ_SET_CONFIGURATION: 1461 if (ctrl->bRequestType != 0) 1462 break; 1463 if (0 == (u8) w_value) { 1464 value = 0; 1465 dev->current_config = 0; 1466 usb_gadget_vbus_draw(gadget, 8 /* mA */ ); 1467 // user mode expected to disable endpoints 1468 } else { 1469 u8 config, power; 1470#ifdef CONFIG_USB_GADGET_DUALSPEED 1471 if (gadget->speed == USB_SPEED_HIGH) { 1472 config = dev->hs_config->bConfigurationValue; 1473 power = dev->hs_config->bMaxPower; 1474 } else 1475#endif 1476 { 1477 config = dev->config->bConfigurationValue; 1478 power = dev->config->bMaxPower; 1479 } 1480 1481 if (config == (u8) w_value) { 1482 value = 0; 1483 dev->current_config = config; 1484 usb_gadget_vbus_draw(gadget, 2 * power); 1485 } 1486 } 1487 1488 /* report SET_CONFIGURATION like any other control request, 1489 * except that usermode may not stall this. the next 1490 * request mustn't be allowed start until this finishes: 1491 * endpoints and threads set up, etc. 1492 * 1493 * NOTE: older PXA hardware (before PXA 255: without UDCCFR) 1494 * has bad/racey automagic that prevents synchronizing here. 1495 * even kernel mode drivers often miss them. 1496 */ 1497 if (value == 0) { 1498 INFO (dev, "configuration #%d\n", dev->current_config); 1499 if (dev->usermode_setup) { 1500 dev->setup_can_stall = 0; 1501 goto delegate; 1502 } 1503 } 1504 break; 1505 1506#ifndef CONFIG_USB_GADGETFS_PXA2XX 1507 /* PXA automagically handles this request too */ 1508 case USB_REQ_GET_CONFIGURATION: 1509 if (ctrl->bRequestType != 0x80) 1510 break; 1511 *(u8 *)req->buf = dev->current_config; 1512 value = min (w_length, (u16) 1); 1513 break; 1514#endif 1515 1516 default: 1517unrecognized: 1518 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n", 1519 dev->usermode_setup ? "delegate" : "fail", 1520 ctrl->bRequestType, ctrl->bRequest, 1521 w_value, le16_to_cpu(ctrl->wIndex), w_length); 1522 1523 /* if there's an ep0 reader, don't stall */ 1524 if (dev->usermode_setup) { 1525 dev->setup_can_stall = 1; 1526delegate: 1527 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN) 1528 ? 1 : 0; 1529 dev->setup_wLength = w_length; 1530 dev->setup_out_ready = 0; 1531 dev->setup_out_error = 0; 1532 value = 0; 1533 1534 /* read DATA stage for OUT right away */ 1535 if (unlikely (!dev->setup_in && w_length)) { 1536 value = setup_req (gadget->ep0, dev->req, 1537 w_length); 1538 if (value < 0) 1539 break; 1540 value = usb_ep_queue (gadget->ep0, dev->req, 1541 GFP_ATOMIC); 1542 if (value < 0) { 1543 clean_req (gadget->ep0, dev->req); 1544 break; 1545 } 1546 1547 /* we can't currently stall these */ 1548 dev->setup_can_stall = 0; 1549 } 1550 1551 /* state changes when reader collects event */ 1552 event = next_event (dev, GADGETFS_SETUP); 1553 event->u.setup = *ctrl; 1554 ep0_readable (dev); 1555 spin_unlock (&dev->lock); 1556 return 0; 1557 } 1558 } 1559 1560 /* proceed with data transfer and status phases? */ 1561 if (value >= 0 && dev->state != STATE_DEV_SETUP) { 1562 req->length = value; 1563 req->zero = value < w_length; 1564 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC); 1565 if (value < 0) { 1566 DBG (dev, "ep_queue --> %d\n", value); 1567 req->status = 0; 1568 } 1569 } 1570 1571 /* device stalls when value < 0 */ 1572 spin_unlock (&dev->lock); 1573 return value; 1574} 1575 1576static void destroy_ep_files (struct dev_data *dev) 1577{ 1578 struct list_head *entry, *tmp; 1579 1580 DBG (dev, "%s %d\n", __FUNCTION__, dev->state); 1581 1582 /* dev->state must prevent interference */ 1583restart: 1584 spin_lock_irq (&dev->lock); 1585 list_for_each_safe (entry, tmp, &dev->epfiles) { 1586 struct ep_data *ep; 1587 struct inode *parent; 1588 struct dentry *dentry; 1589 1590 /* break link to FS */ 1591 ep = list_entry (entry, struct ep_data, epfiles); 1592 list_del_init (&ep->epfiles); 1593 dentry = ep->dentry; 1594 ep->dentry = NULL; 1595 parent = dentry->d_parent->d_inode; 1596 1597 /* break link to controller */ 1598 if (ep->state == STATE_EP_ENABLED) 1599 (void) usb_ep_disable (ep->ep); 1600 ep->state = STATE_EP_UNBOUND; 1601 usb_ep_free_request (ep->ep, ep->req); 1602 ep->ep = NULL; 1603 wake_up (&ep->wait); 1604 put_ep (ep); 1605 1606 spin_unlock_irq (&dev->lock); 1607 1608 /* break link to dcache */ 1609 mutex_lock (&parent->i_mutex); 1610 d_delete (dentry); 1611 dput (dentry); 1612 mutex_unlock (&parent->i_mutex); 1613 1614 /* fds may still be open */ 1615 goto restart; 1616 } 1617 spin_unlock_irq (&dev->lock); 1618} 1619 1620 1621static struct inode * 1622gadgetfs_create_file (struct super_block *sb, char const *name, 1623 void *data, const struct file_operations *fops, 1624 struct dentry **dentry_p); 1625 1626static int activate_ep_files (struct dev_data *dev) 1627{ 1628 struct usb_ep *ep; 1629 struct ep_data *data; 1630 1631 gadget_for_each_ep (ep, dev->gadget) { 1632 1633 data = kzalloc(sizeof(*data), GFP_KERNEL); 1634 if (!data) 1635 goto enomem0; 1636 data->state = STATE_EP_DISABLED; 1637 init_MUTEX (&data->lock); 1638 init_waitqueue_head (&data->wait); 1639 1640 strncpy (data->name, ep->name, sizeof (data->name) - 1); 1641 atomic_set (&data->count, 1); 1642 data->dev = dev; 1643 get_dev (dev); 1644 1645 data->ep = ep; 1646 ep->driver_data = data; 1647 1648 data->req = usb_ep_alloc_request (ep, GFP_KERNEL); 1649 if (!data->req) 1650 goto enomem1; 1651 1652 data->inode = gadgetfs_create_file (dev->sb, data->name, 1653 data, &ep_config_operations, 1654 &data->dentry); 1655 if (!data->inode) 1656 goto enomem2; 1657 list_add_tail (&data->epfiles, &dev->epfiles); 1658 } 1659 return 0; 1660 1661enomem2: 1662 usb_ep_free_request (ep, data->req); 1663enomem1: 1664 put_dev (dev); 1665 kfree (data); 1666enomem0: 1667 DBG (dev, "%s enomem\n", __FUNCTION__); 1668 destroy_ep_files (dev); 1669 return -ENOMEM; 1670} 1671 1672static void 1673gadgetfs_unbind (struct usb_gadget *gadget) 1674{ 1675 struct dev_data *dev = get_gadget_data (gadget); 1676 1677 DBG (dev, "%s\n", __FUNCTION__); 1678 1679 spin_lock_irq (&dev->lock); 1680 dev->state = STATE_DEV_UNBOUND; 1681 spin_unlock_irq (&dev->lock); 1682 1683 destroy_ep_files (dev); 1684 gadget->ep0->driver_data = NULL; 1685 set_gadget_data (gadget, NULL); 1686 1687 /* we've already been disconnected ... no i/o is active */ 1688 if (dev->req) 1689 usb_ep_free_request (gadget->ep0, dev->req); 1690 DBG (dev, "%s done\n", __FUNCTION__); 1691 put_dev (dev); 1692} 1693 1694static struct dev_data *the_device; 1695 1696static int 1697gadgetfs_bind (struct usb_gadget *gadget) 1698{ 1699 struct dev_data *dev = the_device; 1700 1701 if (!dev) 1702 return -ESRCH; 1703 if (0 != strcmp (CHIP, gadget->name)) { 1704 printk (KERN_ERR "%s expected %s controller not %s\n", 1705 shortname, CHIP, gadget->name); 1706 return -ENODEV; 1707 } 1708 1709 set_gadget_data (gadget, dev); 1710 dev->gadget = gadget; 1711 gadget->ep0->driver_data = dev; 1712 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket; 1713 1714 /* preallocate control response and buffer */ 1715 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL); 1716 if (!dev->req) 1717 goto enomem; 1718 dev->req->context = NULL; 1719 dev->req->complete = epio_complete; 1720 1721 if (activate_ep_files (dev) < 0) 1722 goto enomem; 1723 1724 INFO (dev, "bound to %s driver\n", gadget->name); 1725 spin_lock_irq(&dev->lock); 1726 dev->state = STATE_DEV_UNCONNECTED; 1727 spin_unlock_irq(&dev->lock); 1728 get_dev (dev); 1729 return 0; 1730 1731enomem: 1732 gadgetfs_unbind (gadget); 1733 return -ENOMEM; 1734} 1735 1736static void 1737gadgetfs_disconnect (struct usb_gadget *gadget) 1738{ 1739 struct dev_data *dev = get_gadget_data (gadget); 1740 1741 spin_lock (&dev->lock); 1742 if (dev->state == STATE_DEV_UNCONNECTED) 1743 goto exit; 1744 dev->state = STATE_DEV_UNCONNECTED; 1745 1746 INFO (dev, "disconnected\n"); 1747 next_event (dev, GADGETFS_DISCONNECT); 1748 ep0_readable (dev); 1749exit: 1750 spin_unlock (&dev->lock); 1751} 1752 1753static void 1754gadgetfs_suspend (struct usb_gadget *gadget) 1755{ 1756 struct dev_data *dev = get_gadget_data (gadget); 1757 1758 INFO (dev, "suspended from state %d\n", dev->state); 1759 spin_lock (&dev->lock); 1760 switch (dev->state) { 1761 case STATE_DEV_SETUP: // VERY odd... host died?? 1762 case STATE_DEV_CONNECTED: 1763 case STATE_DEV_UNCONNECTED: 1764 next_event (dev, GADGETFS_SUSPEND); 1765 ep0_readable (dev); 1766 /* FALLTHROUGH */ 1767 default: 1768 break; 1769 } 1770 spin_unlock (&dev->lock); 1771} 1772 1773static struct usb_gadget_driver gadgetfs_driver = { 1774#ifdef CONFIG_USB_GADGET_DUALSPEED 1775 .speed = USB_SPEED_HIGH, 1776#else 1777 .speed = USB_SPEED_FULL, 1778#endif 1779 .function = (char *) driver_desc, 1780 .bind = gadgetfs_bind, 1781 .unbind = gadgetfs_unbind, 1782 .setup = gadgetfs_setup, 1783 .disconnect = gadgetfs_disconnect, 1784 .suspend = gadgetfs_suspend, 1785 1786 .driver = { 1787 .name = (char *) shortname, 1788 }, 1789}; 1790 1791/*----------------------------------------------------------------------*/ 1792 1793static void gadgetfs_nop(struct usb_gadget *arg) { } 1794 1795static int gadgetfs_probe (struct usb_gadget *gadget) 1796{ 1797 CHIP = gadget->name; 1798 return -EISNAM; 1799} 1800 1801static struct usb_gadget_driver probe_driver = { 1802 .speed = USB_SPEED_HIGH, 1803 .bind = gadgetfs_probe, 1804 .unbind = gadgetfs_nop, 1805 .setup = (void *)gadgetfs_nop, 1806 .disconnect = gadgetfs_nop, 1807 .driver = { 1808 .name = "nop", 1809 }, 1810}; 1811 1812 1813/* DEVICE INITIALIZATION 1814 * 1815 * fd = open ("/dev/gadget/$CHIP", O_RDWR) 1816 * status = write (fd, descriptors, sizeof descriptors) 1817 * 1818 * That write establishes the device configuration, so the kernel can 1819 * bind to the controller ... guaranteeing it can handle enumeration 1820 * at all necessary speeds. Descriptor order is: 1821 * 1822 * . message tag (u32, host order) ... for now, must be zero; it 1823 * would change to support features like multi-config devices 1824 * . full/low speed config ... all wTotalLength bytes (with interface, 1825 * class, altsetting, endpoint, and other descriptors) 1826 * . high speed config ... all descriptors, for high speed operation; 1827 * this one's optional except for high-speed hardware 1828 * . device descriptor 1829 * 1830 * Endpoints are not yet enabled. Drivers must wait until device 1831 * configuration and interface altsetting changes create 1832 * the need to configure (or unconfigure) them. 1833 * 1834 * After initialization, the device stays active for as long as that 1835 * $CHIP file is open. Events must then be read from that descriptor, 1836 * such as configuration notifications. 1837 */ 1838 1839static int is_valid_config (struct usb_config_descriptor *config) 1840{ 1841 return config->bDescriptorType == USB_DT_CONFIG 1842 && config->bLength == USB_DT_CONFIG_SIZE 1843 && config->bConfigurationValue != 0 1844 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0 1845 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0; 1846 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */ 1847 /* FIXME check lengths: walk to end */ 1848} 1849 1850static ssize_t 1851dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 1852{ 1853 struct dev_data *dev = fd->private_data; 1854 ssize_t value = len, length = len; 1855 unsigned total; 1856 u32 tag; 1857 char *kbuf; 1858 1859 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) 1860 return -EINVAL; 1861 1862 /* we might need to change message format someday */ 1863 if (copy_from_user (&tag, buf, 4)) 1864 return -EFAULT; 1865 if (tag != 0) 1866 return -EINVAL; 1867 buf += 4; 1868 length -= 4; 1869 1870 kbuf = kmalloc (length, GFP_KERNEL); 1871 if (!kbuf) 1872 return -ENOMEM; 1873 if (copy_from_user (kbuf, buf, length)) { 1874 kfree (kbuf); 1875 return -EFAULT; 1876 } 1877 1878 spin_lock_irq (&dev->lock); 1879 value = -EINVAL; 1880 if (dev->buf) 1881 goto fail; 1882 dev->buf = kbuf; 1883 1884 /* full or low speed config */ 1885 dev->config = (void *) kbuf; 1886 total = le16_to_cpup (&dev->config->wTotalLength); 1887 if (!is_valid_config (dev->config) || total >= length) 1888 goto fail; 1889 kbuf += total; 1890 length -= total; 1891 1892 /* optional high speed config */ 1893 if (kbuf [1] == USB_DT_CONFIG) { 1894 dev->hs_config = (void *) kbuf; 1895 total = le16_to_cpup (&dev->hs_config->wTotalLength); 1896 if (!is_valid_config (dev->hs_config) || total >= length) 1897 goto fail; 1898 kbuf += total; 1899 length -= total; 1900 } 1901 1902 /* could support multiple configs, using another encoding! */ 1903 1904 /* device descriptor (tweaked for paranoia) */ 1905 if (length != USB_DT_DEVICE_SIZE) 1906 goto fail; 1907 dev->dev = (void *)kbuf; 1908 if (dev->dev->bLength != USB_DT_DEVICE_SIZE 1909 || dev->dev->bDescriptorType != USB_DT_DEVICE 1910 || dev->dev->bNumConfigurations != 1) 1911 goto fail; 1912 dev->dev->bNumConfigurations = 1; 1913 dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200); 1914 1915 /* triggers gadgetfs_bind(); then we can enumerate. */ 1916 spin_unlock_irq (&dev->lock); 1917 value = usb_gadget_register_driver (&gadgetfs_driver); 1918 if (value != 0) { 1919 kfree (dev->buf); 1920 dev->buf = NULL; 1921 } else { 1922 /* at this point "good" hardware has for the first time 1923 * let the USB the host see us. alternatively, if users 1924 * unplug/replug that will clear all the error state. 1925 * 1926 * note: everything running before here was guaranteed 1927 * to choke driver model style diagnostics. from here 1928 * on, they can work ... except in cleanup paths that 1929 * kick in after the ep0 descriptor is closed. 1930 */ 1931 fd->f_op = &ep0_io_operations; 1932 value = len; 1933 } 1934 return value; 1935 1936fail: 1937 spin_unlock_irq (&dev->lock); 1938 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev); 1939 kfree (dev->buf); 1940 dev->buf = NULL; 1941 return value; 1942} 1943 1944static int 1945dev_open (struct inode *inode, struct file *fd) 1946{ 1947 struct dev_data *dev = inode->i_private; 1948 int value = -EBUSY; 1949 1950 spin_lock_irq(&dev->lock); 1951 if (dev->state == STATE_DEV_DISABLED) { 1952 dev->ev_next = 0; 1953 dev->state = STATE_DEV_OPENED; 1954 fd->private_data = dev; 1955 get_dev (dev); 1956 value = 0; 1957 } 1958 spin_unlock_irq(&dev->lock); 1959 return value; 1960} 1961 1962static const struct file_operations dev_init_operations = { 1963 .owner = THIS_MODULE, 1964 .llseek = no_llseek, 1965 1966 .open = dev_open, 1967 .write = dev_config, 1968 .fasync = ep0_fasync, 1969 .ioctl = dev_ioctl, 1970 .release = dev_release, 1971}; 1972 1973/*----------------------------------------------------------------------*/ 1974 1975/* FILESYSTEM AND SUPERBLOCK OPERATIONS 1976 * 1977 * Mounting the filesystem creates a controller file, used first for 1978 * device configuration then later for event monitoring. 1979 */ 1980 1981 1982/* FIXME PAM etc could set this security policy without mount options 1983 * if epfiles inherited ownership and permissons from ep0 ... 1984 */ 1985 1986static unsigned default_uid; 1987static unsigned default_gid; 1988static unsigned default_perm = S_IRUSR | S_IWUSR; 1989 1990module_param (default_uid, uint, 0644); 1991module_param (default_gid, uint, 0644); 1992module_param (default_perm, uint, 0644); 1993 1994 1995static struct inode * 1996gadgetfs_make_inode (struct super_block *sb, 1997 void *data, const struct file_operations *fops, 1998 int mode) 1999{ 2000 struct inode *inode = new_inode (sb); 2001 2002 if (inode) { 2003 inode->i_mode = mode; 2004 inode->i_uid = default_uid; 2005 inode->i_gid = default_gid; 2006 inode->i_blocks = 0; 2007 inode->i_atime = inode->i_mtime = inode->i_ctime 2008 = CURRENT_TIME; 2009 inode->i_private = data; 2010 inode->i_fop = fops; 2011 } 2012 return inode; 2013} 2014 2015/* creates in fs root directory, so non-renamable and non-linkable. 2016 * so inode and dentry are paired, until device reconfig. 2017 */ 2018static struct inode * 2019gadgetfs_create_file (struct super_block *sb, char const *name, 2020 void *data, const struct file_operations *fops, 2021 struct dentry **dentry_p) 2022{ 2023 struct dentry *dentry; 2024 struct inode *inode; 2025 2026 dentry = d_alloc_name(sb->s_root, name); 2027 if (!dentry) 2028 return NULL; 2029 2030 inode = gadgetfs_make_inode (sb, data, fops, 2031 S_IFREG | (default_perm & S_IRWXUGO)); 2032 if (!inode) { 2033 dput(dentry); 2034 return NULL; 2035 } 2036 d_add (dentry, inode); 2037 *dentry_p = dentry; 2038 return inode; 2039} 2040 2041static struct super_operations gadget_fs_operations = { 2042 .statfs = simple_statfs, 2043 .drop_inode = generic_delete_inode, 2044}; 2045 2046static int 2047gadgetfs_fill_super (struct super_block *sb, void *opts, int silent) 2048{ 2049 struct inode *inode; 2050 struct dentry *d; 2051 struct dev_data *dev; 2052 2053 if (the_device) 2054 return -ESRCH; 2055 2056 /* fake probe to determine $CHIP */ 2057 (void) usb_gadget_register_driver (&probe_driver); 2058 if (!CHIP) 2059 return -ENODEV; 2060 2061 /* superblock */ 2062 sb->s_blocksize = PAGE_CACHE_SIZE; 2063 sb->s_blocksize_bits = PAGE_CACHE_SHIFT; 2064 sb->s_magic = GADGETFS_MAGIC; 2065 sb->s_op = &gadget_fs_operations; 2066 sb->s_time_gran = 1; 2067 2068 /* root inode */ 2069 inode = gadgetfs_make_inode (sb, 2070 NULL, &simple_dir_operations, 2071 S_IFDIR | S_IRUGO | S_IXUGO); 2072 if (!inode) 2073 goto enomem0; 2074 inode->i_op = &simple_dir_inode_operations; 2075 if (!(d = d_alloc_root (inode))) 2076 goto enomem1; 2077 sb->s_root = d; 2078 2079 /* the ep0 file is named after the controller we expect; 2080 * user mode code can use it for sanity checks, like we do. 2081 */ 2082 dev = dev_new (); 2083 if (!dev) 2084 goto enomem2; 2085 2086 dev->sb = sb; 2087 if (!gadgetfs_create_file (sb, CHIP, 2088 dev, &dev_init_operations, 2089 &dev->dentry)) 2090 goto enomem3; 2091 2092 /* other endpoint files are available after hardware setup, 2093 * from binding to a controller. 2094 */ 2095 the_device = dev; 2096 return 0; 2097 2098enomem3: 2099 put_dev (dev); 2100enomem2: 2101 dput (d); 2102enomem1: 2103 iput (inode); 2104enomem0: 2105 return -ENOMEM; 2106} 2107 2108/* "mount -t gadgetfs path /dev/gadget" ends up here */ 2109static int 2110gadgetfs_get_sb (struct file_system_type *t, int flags, 2111 const char *path, void *opts, struct vfsmount *mnt) 2112{ 2113 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt); 2114} 2115 2116static void 2117gadgetfs_kill_sb (struct super_block *sb) 2118{ 2119 kill_litter_super (sb); 2120 if (the_device) { 2121 put_dev (the_device); 2122 the_device = NULL; 2123 } 2124} 2125 2126/*----------------------------------------------------------------------*/ 2127 2128static struct file_system_type gadgetfs_type = { 2129 .owner = THIS_MODULE, 2130 .name = shortname, 2131 .get_sb = gadgetfs_get_sb, 2132 .kill_sb = gadgetfs_kill_sb, 2133}; 2134 2135/*----------------------------------------------------------------------*/ 2136 2137static int __init init (void) 2138{ 2139 int status; 2140 2141 status = register_filesystem (&gadgetfs_type); 2142 if (status == 0) 2143 pr_info ("%s: %s, version " DRIVER_VERSION "\n", 2144 shortname, driver_desc); 2145 return status; 2146} 2147module_init (init); 2148 2149static void __exit cleanup (void) 2150{ 2151 pr_debug ("unregister %s\n", shortname); 2152 unregister_filesystem (&gadgetfs_type); 2153} 2154module_exit (cleanup); 2155 2156