inode.c revision ce46794f77f698eaf3b80922fafac5a9379085e0
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 unsigned long flags; 937 int free = 1; 938 939 /* for control OUT, data must still get to userspace */ 940 spin_lock_irqsave(&dev->lock, flags); 941 if (!dev->setup_in) { 942 dev->setup_out_error = (req->status != 0); 943 if (!dev->setup_out_error) 944 free = 0; 945 dev->setup_out_ready = 1; 946 ep0_readable (dev); 947 } 948 949 /* clean up as appropriate */ 950 if (free && req->buf != &dev->rbuf) 951 clean_req (ep, req); 952 req->complete = epio_complete; 953 spin_unlock_irqrestore(&dev->lock, flags); 954} 955 956static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len) 957{ 958 struct dev_data *dev = ep->driver_data; 959 960 if (dev->setup_out_ready) { 961 DBG (dev, "ep0 request busy!\n"); 962 return -EBUSY; 963 } 964 if (len > sizeof (dev->rbuf)) 965 req->buf = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC); 966 if (req->buf == 0) { 967 req->buf = dev->rbuf; 968 return -ENOMEM; 969 } 970 req->complete = ep0_complete; 971 req->length = len; 972 req->zero = 0; 973 return 0; 974} 975 976static ssize_t 977ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) 978{ 979 struct dev_data *dev = fd->private_data; 980 ssize_t retval; 981 enum ep0_state state; 982 983 spin_lock_irq (&dev->lock); 984 985 /* report fd mode change before acting on it */ 986 if (dev->setup_abort) { 987 dev->setup_abort = 0; 988 retval = -EIDRM; 989 goto done; 990 } 991 992 /* control DATA stage */ 993 if ((state = dev->state) == STATE_DEV_SETUP) { 994 995 if (dev->setup_in) { /* stall IN */ 996 VDEBUG(dev, "ep0in stall\n"); 997 (void) usb_ep_set_halt (dev->gadget->ep0); 998 retval = -EL2HLT; 999 dev->state = STATE_DEV_CONNECTED; 1000 1001 } else if (len == 0) { /* ack SET_CONFIGURATION etc */ 1002 struct usb_ep *ep = dev->gadget->ep0; 1003 struct usb_request *req = dev->req; 1004 1005 if ((retval = setup_req (ep, req, 0)) == 0) 1006 retval = usb_ep_queue (ep, req, GFP_ATOMIC); 1007 dev->state = STATE_DEV_CONNECTED; 1008 1009 /* assume that was SET_CONFIGURATION */ 1010 if (dev->current_config) { 1011 unsigned power; 1012#ifdef CONFIG_USB_GADGET_DUALSPEED 1013 if (dev->gadget->speed == USB_SPEED_HIGH) 1014 power = dev->hs_config->bMaxPower; 1015 else 1016#endif 1017 power = dev->config->bMaxPower; 1018 usb_gadget_vbus_draw(dev->gadget, 2 * power); 1019 } 1020 1021 } else { /* collect OUT data */ 1022 if ((fd->f_flags & O_NONBLOCK) != 0 1023 && !dev->setup_out_ready) { 1024 retval = -EAGAIN; 1025 goto done; 1026 } 1027 spin_unlock_irq (&dev->lock); 1028 retval = wait_event_interruptible (dev->wait, 1029 dev->setup_out_ready != 0); 1030 1031 /* FIXME state could change from under us */ 1032 spin_lock_irq (&dev->lock); 1033 if (retval) 1034 goto done; 1035 1036 if (dev->state != STATE_DEV_SETUP) { 1037 retval = -ECANCELED; 1038 goto done; 1039 } 1040 dev->state = STATE_DEV_CONNECTED; 1041 1042 if (dev->setup_out_error) 1043 retval = -EIO; 1044 else { 1045 len = min (len, (size_t)dev->req->actual); 1046// FIXME don't call this with the spinlock held ... 1047 if (copy_to_user (buf, dev->req->buf, len)) 1048 retval = -EFAULT; 1049 clean_req (dev->gadget->ep0, dev->req); 1050 /* NOTE userspace can't yet choose to stall */ 1051 } 1052 } 1053 goto done; 1054 } 1055 1056 /* else normal: return event data */ 1057 if (len < sizeof dev->event [0]) { 1058 retval = -EINVAL; 1059 goto done; 1060 } 1061 len -= len % sizeof (struct usb_gadgetfs_event); 1062 dev->usermode_setup = 1; 1063 1064scan: 1065 /* return queued events right away */ 1066 if (dev->ev_next != 0) { 1067 unsigned i, n; 1068 1069 n = len / sizeof (struct usb_gadgetfs_event); 1070 if (dev->ev_next < n) 1071 n = dev->ev_next; 1072 1073 /* ep0 i/o has special semantics during STATE_DEV_SETUP */ 1074 for (i = 0; i < n; i++) { 1075 if (dev->event [i].type == GADGETFS_SETUP) { 1076 dev->state = STATE_DEV_SETUP; 1077 n = i + 1; 1078 break; 1079 } 1080 } 1081 spin_unlock_irq (&dev->lock); 1082 len = n * sizeof (struct usb_gadgetfs_event); 1083 if (copy_to_user (buf, &dev->event, len)) 1084 retval = -EFAULT; 1085 else 1086 retval = len; 1087 if (len > 0) { 1088 /* NOTE this doesn't guard against broken drivers; 1089 * concurrent ep0 readers may lose events. 1090 */ 1091 spin_lock_irq (&dev->lock); 1092 if (dev->ev_next > n) { 1093 memmove(&dev->event[0], &dev->event[n], 1094 sizeof (struct usb_gadgetfs_event) 1095 * (dev->ev_next - n)); 1096 } 1097 dev->ev_next -= n; 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] %d\n", i, 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 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type); 1166 event = &dev->event [dev->ev_next++]; 1167 BUG_ON (dev->ev_next > N_EVENT); 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 dev->state = STATE_DEV_CONNECTED; 1194 spin_unlock_irq (&dev->lock); 1195 if (copy_from_user (dev->req->buf, buf, len)) 1196 retval = -EFAULT; 1197 else { 1198 if (len < dev->setup_wLength) 1199 dev->req->zero = 1; 1200 retval = usb_ep_queue ( 1201 dev->gadget->ep0, dev->req, 1202 GFP_KERNEL); 1203 } 1204 if (retval < 0) { 1205 spin_lock_irq (&dev->lock); 1206 clean_req (dev->gadget->ep0, dev->req); 1207 spin_unlock_irq (&dev->lock); 1208 } else 1209 retval = len; 1210 1211 return retval; 1212 } 1213 1214 /* can stall some OUT transfers */ 1215 } else if (dev->setup_can_stall) { 1216 VDEBUG(dev, "ep0out stall\n"); 1217 (void) usb_ep_set_halt (dev->gadget->ep0); 1218 retval = -EL2HLT; 1219 dev->state = STATE_DEV_CONNECTED; 1220 } else { 1221 DBG(dev, "bogus ep0out stall!\n"); 1222 } 1223 } else 1224 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state); 1225 1226 spin_unlock_irq (&dev->lock); 1227 return retval; 1228} 1229 1230static int 1231ep0_fasync (int f, struct file *fd, int on) 1232{ 1233 struct dev_data *dev = fd->private_data; 1234 // caller must F_SETOWN before signal delivery happens 1235 VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off"); 1236 return fasync_helper (f, fd, on, &dev->fasync); 1237} 1238 1239static struct usb_gadget_driver gadgetfs_driver; 1240 1241static int 1242dev_release (struct inode *inode, struct file *fd) 1243{ 1244 struct dev_data *dev = fd->private_data; 1245 1246 /* closing ep0 === shutdown all */ 1247 1248 usb_gadget_unregister_driver (&gadgetfs_driver); 1249 1250 /* at this point "good" hardware has disconnected the 1251 * device from USB; the host won't see it any more. 1252 * alternatively, all host requests will time out. 1253 */ 1254 1255 fasync_helper (-1, fd, 0, &dev->fasync); 1256 kfree (dev->buf); 1257 dev->buf = NULL; 1258 put_dev (dev); 1259 1260 /* other endpoints were all decoupled from this device */ 1261 spin_lock_irq(&dev->lock); 1262 dev->state = STATE_DEV_DISABLED; 1263 spin_unlock_irq(&dev->lock); 1264 return 0; 1265} 1266 1267static unsigned int 1268ep0_poll (struct file *fd, poll_table *wait) 1269{ 1270 struct dev_data *dev = fd->private_data; 1271 int mask = 0; 1272 1273 poll_wait(fd, &dev->wait, wait); 1274 1275 spin_lock_irq (&dev->lock); 1276 1277 /* report fd mode change before acting on it */ 1278 if (dev->setup_abort) { 1279 dev->setup_abort = 0; 1280 mask = POLLHUP; 1281 goto out; 1282 } 1283 1284 if (dev->state == STATE_DEV_SETUP) { 1285 if (dev->setup_in || dev->setup_can_stall) 1286 mask = POLLOUT; 1287 } else { 1288 if (dev->ev_next != 0) 1289 mask = POLLIN; 1290 } 1291out: 1292 spin_unlock_irq(&dev->lock); 1293 return mask; 1294} 1295 1296static int dev_ioctl (struct inode *inode, struct file *fd, 1297 unsigned code, unsigned long value) 1298{ 1299 struct dev_data *dev = fd->private_data; 1300 struct usb_gadget *gadget = dev->gadget; 1301 1302 if (gadget->ops->ioctl) 1303 return gadget->ops->ioctl (gadget, code, value); 1304 return -ENOTTY; 1305} 1306 1307/* used after device configuration */ 1308static const struct file_operations ep0_io_operations = { 1309 .owner = THIS_MODULE, 1310 .llseek = no_llseek, 1311 1312 .read = ep0_read, 1313 .write = ep0_write, 1314 .fasync = ep0_fasync, 1315 .poll = ep0_poll, 1316 .ioctl = dev_ioctl, 1317 .release = dev_release, 1318}; 1319 1320/*----------------------------------------------------------------------*/ 1321 1322/* The in-kernel gadget driver handles most ep0 issues, in particular 1323 * enumerating the single configuration (as provided from user space). 1324 * 1325 * Unrecognized ep0 requests may be handled in user space. 1326 */ 1327 1328#ifdef CONFIG_USB_GADGET_DUALSPEED 1329static void make_qualifier (struct dev_data *dev) 1330{ 1331 struct usb_qualifier_descriptor qual; 1332 struct usb_device_descriptor *desc; 1333 1334 qual.bLength = sizeof qual; 1335 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER; 1336 qual.bcdUSB = __constant_cpu_to_le16 (0x0200); 1337 1338 desc = dev->dev; 1339 qual.bDeviceClass = desc->bDeviceClass; 1340 qual.bDeviceSubClass = desc->bDeviceSubClass; 1341 qual.bDeviceProtocol = desc->bDeviceProtocol; 1342 1343 /* assumes ep0 uses the same value for both speeds ... */ 1344 qual.bMaxPacketSize0 = desc->bMaxPacketSize0; 1345 1346 qual.bNumConfigurations = 1; 1347 qual.bRESERVED = 0; 1348 1349 memcpy (dev->rbuf, &qual, sizeof qual); 1350} 1351#endif 1352 1353static int 1354config_buf (struct dev_data *dev, u8 type, unsigned index) 1355{ 1356 int len; 1357#ifdef CONFIG_USB_GADGET_DUALSPEED 1358 int hs; 1359#endif 1360 1361 /* only one configuration */ 1362 if (index > 0) 1363 return -EINVAL; 1364 1365#ifdef CONFIG_USB_GADGET_DUALSPEED 1366 hs = (dev->gadget->speed == USB_SPEED_HIGH); 1367 if (type == USB_DT_OTHER_SPEED_CONFIG) 1368 hs = !hs; 1369 if (hs) { 1370 dev->req->buf = dev->hs_config; 1371 len = le16_to_cpup (&dev->hs_config->wTotalLength); 1372 } else 1373#endif 1374 { 1375 dev->req->buf = dev->config; 1376 len = le16_to_cpup (&dev->config->wTotalLength); 1377 } 1378 ((u8 *)dev->req->buf) [1] = type; 1379 return len; 1380} 1381 1382static int 1383gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) 1384{ 1385 struct dev_data *dev = get_gadget_data (gadget); 1386 struct usb_request *req = dev->req; 1387 int value = -EOPNOTSUPP; 1388 struct usb_gadgetfs_event *event; 1389 u16 w_value = le16_to_cpu(ctrl->wValue); 1390 u16 w_length = le16_to_cpu(ctrl->wLength); 1391 1392 spin_lock (&dev->lock); 1393 dev->setup_abort = 0; 1394 if (dev->state == STATE_DEV_UNCONNECTED) { 1395#ifdef CONFIG_USB_GADGET_DUALSPEED 1396 if (gadget->speed == USB_SPEED_HIGH && dev->hs_config == 0) { 1397 spin_unlock(&dev->lock); 1398 ERROR (dev, "no high speed config??\n"); 1399 return -EINVAL; 1400 } 1401#endif /* CONFIG_USB_GADGET_DUALSPEED */ 1402 1403 dev->state = STATE_DEV_CONNECTED; 1404 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket; 1405 1406 INFO (dev, "connected\n"); 1407 event = next_event (dev, GADGETFS_CONNECT); 1408 event->u.speed = gadget->speed; 1409 ep0_readable (dev); 1410 1411 /* host may have given up waiting for response. we can miss control 1412 * requests handled lower down (device/endpoint status and features); 1413 * then ep0_{read,write} will report the wrong status. controller 1414 * driver will have aborted pending i/o. 1415 */ 1416 } else if (dev->state == STATE_DEV_SETUP) 1417 dev->setup_abort = 1; 1418 1419 req->buf = dev->rbuf; 1420 req->dma = DMA_ADDR_INVALID; 1421 req->context = NULL; 1422 value = -EOPNOTSUPP; 1423 switch (ctrl->bRequest) { 1424 1425 case USB_REQ_GET_DESCRIPTOR: 1426 if (ctrl->bRequestType != USB_DIR_IN) 1427 goto unrecognized; 1428 switch (w_value >> 8) { 1429 1430 case USB_DT_DEVICE: 1431 value = min (w_length, (u16) sizeof *dev->dev); 1432 req->buf = dev->dev; 1433 break; 1434#ifdef CONFIG_USB_GADGET_DUALSPEED 1435 case USB_DT_DEVICE_QUALIFIER: 1436 if (!dev->hs_config) 1437 break; 1438 value = min (w_length, (u16) 1439 sizeof (struct usb_qualifier_descriptor)); 1440 make_qualifier (dev); 1441 break; 1442 case USB_DT_OTHER_SPEED_CONFIG: 1443 // FALLTHROUGH 1444#endif 1445 case USB_DT_CONFIG: 1446 value = config_buf (dev, 1447 w_value >> 8, 1448 w_value & 0xff); 1449 if (value >= 0) 1450 value = min (w_length, (u16) value); 1451 break; 1452 case USB_DT_STRING: 1453 goto unrecognized; 1454 1455 default: // all others are errors 1456 break; 1457 } 1458 break; 1459 1460 /* currently one config, two speeds */ 1461 case USB_REQ_SET_CONFIGURATION: 1462 if (ctrl->bRequestType != 0) 1463 break; 1464 if (0 == (u8) w_value) { 1465 value = 0; 1466 dev->current_config = 0; 1467 usb_gadget_vbus_draw(gadget, 8 /* mA */ ); 1468 // user mode expected to disable endpoints 1469 } else { 1470 u8 config, power; 1471#ifdef CONFIG_USB_GADGET_DUALSPEED 1472 if (gadget->speed == USB_SPEED_HIGH) { 1473 config = dev->hs_config->bConfigurationValue; 1474 power = dev->hs_config->bMaxPower; 1475 } else 1476#endif 1477 { 1478 config = dev->config->bConfigurationValue; 1479 power = dev->config->bMaxPower; 1480 } 1481 1482 if (config == (u8) w_value) { 1483 value = 0; 1484 dev->current_config = config; 1485 usb_gadget_vbus_draw(gadget, 2 * power); 1486 } 1487 } 1488 1489 /* report SET_CONFIGURATION like any other control request, 1490 * except that usermode may not stall this. the next 1491 * request mustn't be allowed start until this finishes: 1492 * endpoints and threads set up, etc. 1493 * 1494 * NOTE: older PXA hardware (before PXA 255: without UDCCFR) 1495 * has bad/racey automagic that prevents synchronizing here. 1496 * even kernel mode drivers often miss them. 1497 */ 1498 if (value == 0) { 1499 INFO (dev, "configuration #%d\n", dev->current_config); 1500 if (dev->usermode_setup) { 1501 dev->setup_can_stall = 0; 1502 goto delegate; 1503 } 1504 } 1505 break; 1506 1507#ifndef CONFIG_USB_GADGETFS_PXA2XX 1508 /* PXA automagically handles this request too */ 1509 case USB_REQ_GET_CONFIGURATION: 1510 if (ctrl->bRequestType != 0x80) 1511 break; 1512 *(u8 *)req->buf = dev->current_config; 1513 value = min (w_length, (u16) 1); 1514 break; 1515#endif 1516 1517 default: 1518unrecognized: 1519 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n", 1520 dev->usermode_setup ? "delegate" : "fail", 1521 ctrl->bRequestType, ctrl->bRequest, 1522 w_value, le16_to_cpu(ctrl->wIndex), w_length); 1523 1524 /* if there's an ep0 reader, don't stall */ 1525 if (dev->usermode_setup) { 1526 dev->setup_can_stall = 1; 1527delegate: 1528 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN) 1529 ? 1 : 0; 1530 dev->setup_wLength = w_length; 1531 dev->setup_out_ready = 0; 1532 dev->setup_out_error = 0; 1533 value = 0; 1534 1535 /* read DATA stage for OUT right away */ 1536 if (unlikely (!dev->setup_in && w_length)) { 1537 value = setup_req (gadget->ep0, dev->req, 1538 w_length); 1539 if (value < 0) 1540 break; 1541 value = usb_ep_queue (gadget->ep0, dev->req, 1542 GFP_ATOMIC); 1543 if (value < 0) { 1544 clean_req (gadget->ep0, dev->req); 1545 break; 1546 } 1547 1548 /* we can't currently stall these */ 1549 dev->setup_can_stall = 0; 1550 } 1551 1552 /* state changes when reader collects event */ 1553 event = next_event (dev, GADGETFS_SETUP); 1554 event->u.setup = *ctrl; 1555 ep0_readable (dev); 1556 spin_unlock (&dev->lock); 1557 return 0; 1558 } 1559 } 1560 1561 /* proceed with data transfer and status phases? */ 1562 if (value >= 0 && dev->state != STATE_DEV_SETUP) { 1563 req->length = value; 1564 req->zero = value < w_length; 1565 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC); 1566 if (value < 0) { 1567 DBG (dev, "ep_queue --> %d\n", value); 1568 req->status = 0; 1569 } 1570 } 1571 1572 /* device stalls when value < 0 */ 1573 spin_unlock (&dev->lock); 1574 return value; 1575} 1576 1577static void destroy_ep_files (struct dev_data *dev) 1578{ 1579 struct list_head *entry, *tmp; 1580 1581 DBG (dev, "%s %d\n", __FUNCTION__, dev->state); 1582 1583 /* dev->state must prevent interference */ 1584restart: 1585 spin_lock_irq (&dev->lock); 1586 list_for_each_safe (entry, tmp, &dev->epfiles) { 1587 struct ep_data *ep; 1588 struct inode *parent; 1589 struct dentry *dentry; 1590 1591 /* break link to FS */ 1592 ep = list_entry (entry, struct ep_data, epfiles); 1593 list_del_init (&ep->epfiles); 1594 dentry = ep->dentry; 1595 ep->dentry = NULL; 1596 parent = dentry->d_parent->d_inode; 1597 1598 /* break link to controller */ 1599 if (ep->state == STATE_EP_ENABLED) 1600 (void) usb_ep_disable (ep->ep); 1601 ep->state = STATE_EP_UNBOUND; 1602 usb_ep_free_request (ep->ep, ep->req); 1603 ep->ep = NULL; 1604 wake_up (&ep->wait); 1605 put_ep (ep); 1606 1607 spin_unlock_irq (&dev->lock); 1608 1609 /* break link to dcache */ 1610 mutex_lock (&parent->i_mutex); 1611 d_delete (dentry); 1612 dput (dentry); 1613 mutex_unlock (&parent->i_mutex); 1614 1615 /* fds may still be open */ 1616 goto restart; 1617 } 1618 spin_unlock_irq (&dev->lock); 1619} 1620 1621 1622static struct inode * 1623gadgetfs_create_file (struct super_block *sb, char const *name, 1624 void *data, const struct file_operations *fops, 1625 struct dentry **dentry_p); 1626 1627static int activate_ep_files (struct dev_data *dev) 1628{ 1629 struct usb_ep *ep; 1630 struct ep_data *data; 1631 1632 gadget_for_each_ep (ep, dev->gadget) { 1633 1634 data = kzalloc(sizeof(*data), GFP_KERNEL); 1635 if (!data) 1636 goto enomem0; 1637 data->state = STATE_EP_DISABLED; 1638 init_MUTEX (&data->lock); 1639 init_waitqueue_head (&data->wait); 1640 1641 strncpy (data->name, ep->name, sizeof (data->name) - 1); 1642 atomic_set (&data->count, 1); 1643 data->dev = dev; 1644 get_dev (dev); 1645 1646 data->ep = ep; 1647 ep->driver_data = data; 1648 1649 data->req = usb_ep_alloc_request (ep, GFP_KERNEL); 1650 if (!data->req) 1651 goto enomem1; 1652 1653 data->inode = gadgetfs_create_file (dev->sb, data->name, 1654 data, &ep_config_operations, 1655 &data->dentry); 1656 if (!data->inode) 1657 goto enomem2; 1658 list_add_tail (&data->epfiles, &dev->epfiles); 1659 } 1660 return 0; 1661 1662enomem2: 1663 usb_ep_free_request (ep, data->req); 1664enomem1: 1665 put_dev (dev); 1666 kfree (data); 1667enomem0: 1668 DBG (dev, "%s enomem\n", __FUNCTION__); 1669 destroy_ep_files (dev); 1670 return -ENOMEM; 1671} 1672 1673static void 1674gadgetfs_unbind (struct usb_gadget *gadget) 1675{ 1676 struct dev_data *dev = get_gadget_data (gadget); 1677 1678 DBG (dev, "%s\n", __FUNCTION__); 1679 1680 spin_lock_irq (&dev->lock); 1681 dev->state = STATE_DEV_UNBOUND; 1682 spin_unlock_irq (&dev->lock); 1683 1684 destroy_ep_files (dev); 1685 gadget->ep0->driver_data = NULL; 1686 set_gadget_data (gadget, NULL); 1687 1688 /* we've already been disconnected ... no i/o is active */ 1689 if (dev->req) 1690 usb_ep_free_request (gadget->ep0, dev->req); 1691 DBG (dev, "%s done\n", __FUNCTION__); 1692 put_dev (dev); 1693} 1694 1695static struct dev_data *the_device; 1696 1697static int 1698gadgetfs_bind (struct usb_gadget *gadget) 1699{ 1700 struct dev_data *dev = the_device; 1701 1702 if (!dev) 1703 return -ESRCH; 1704 if (0 != strcmp (CHIP, gadget->name)) { 1705 printk (KERN_ERR "%s expected %s controller not %s\n", 1706 shortname, CHIP, gadget->name); 1707 return -ENODEV; 1708 } 1709 1710 set_gadget_data (gadget, dev); 1711 dev->gadget = gadget; 1712 gadget->ep0->driver_data = dev; 1713 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket; 1714 1715 /* preallocate control response and buffer */ 1716 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL); 1717 if (!dev->req) 1718 goto enomem; 1719 dev->req->context = NULL; 1720 dev->req->complete = epio_complete; 1721 1722 if (activate_ep_files (dev) < 0) 1723 goto enomem; 1724 1725 INFO (dev, "bound to %s driver\n", gadget->name); 1726 spin_lock_irq(&dev->lock); 1727 dev->state = STATE_DEV_UNCONNECTED; 1728 spin_unlock_irq(&dev->lock); 1729 get_dev (dev); 1730 return 0; 1731 1732enomem: 1733 gadgetfs_unbind (gadget); 1734 return -ENOMEM; 1735} 1736 1737static void 1738gadgetfs_disconnect (struct usb_gadget *gadget) 1739{ 1740 struct dev_data *dev = get_gadget_data (gadget); 1741 1742 spin_lock (&dev->lock); 1743 if (dev->state == STATE_DEV_UNCONNECTED) 1744 goto exit; 1745 dev->state = STATE_DEV_UNCONNECTED; 1746 1747 INFO (dev, "disconnected\n"); 1748 next_event (dev, GADGETFS_DISCONNECT); 1749 ep0_readable (dev); 1750exit: 1751 spin_unlock (&dev->lock); 1752} 1753 1754static void 1755gadgetfs_suspend (struct usb_gadget *gadget) 1756{ 1757 struct dev_data *dev = get_gadget_data (gadget); 1758 1759 INFO (dev, "suspended from state %d\n", dev->state); 1760 spin_lock (&dev->lock); 1761 switch (dev->state) { 1762 case STATE_DEV_SETUP: // VERY odd... host died?? 1763 case STATE_DEV_CONNECTED: 1764 case STATE_DEV_UNCONNECTED: 1765 next_event (dev, GADGETFS_SUSPEND); 1766 ep0_readable (dev); 1767 /* FALLTHROUGH */ 1768 default: 1769 break; 1770 } 1771 spin_unlock (&dev->lock); 1772} 1773 1774static struct usb_gadget_driver gadgetfs_driver = { 1775#ifdef CONFIG_USB_GADGET_DUALSPEED 1776 .speed = USB_SPEED_HIGH, 1777#else 1778 .speed = USB_SPEED_FULL, 1779#endif 1780 .function = (char *) driver_desc, 1781 .bind = gadgetfs_bind, 1782 .unbind = gadgetfs_unbind, 1783 .setup = gadgetfs_setup, 1784 .disconnect = gadgetfs_disconnect, 1785 .suspend = gadgetfs_suspend, 1786 1787 .driver = { 1788 .name = (char *) shortname, 1789 }, 1790}; 1791 1792/*----------------------------------------------------------------------*/ 1793 1794static void gadgetfs_nop(struct usb_gadget *arg) { } 1795 1796static int gadgetfs_probe (struct usb_gadget *gadget) 1797{ 1798 CHIP = gadget->name; 1799 return -EISNAM; 1800} 1801 1802static struct usb_gadget_driver probe_driver = { 1803 .speed = USB_SPEED_HIGH, 1804 .bind = gadgetfs_probe, 1805 .unbind = gadgetfs_nop, 1806 .setup = (void *)gadgetfs_nop, 1807 .disconnect = gadgetfs_nop, 1808 .driver = { 1809 .name = "nop", 1810 }, 1811}; 1812 1813 1814/* DEVICE INITIALIZATION 1815 * 1816 * fd = open ("/dev/gadget/$CHIP", O_RDWR) 1817 * status = write (fd, descriptors, sizeof descriptors) 1818 * 1819 * That write establishes the device configuration, so the kernel can 1820 * bind to the controller ... guaranteeing it can handle enumeration 1821 * at all necessary speeds. Descriptor order is: 1822 * 1823 * . message tag (u32, host order) ... for now, must be zero; it 1824 * would change to support features like multi-config devices 1825 * . full/low speed config ... all wTotalLength bytes (with interface, 1826 * class, altsetting, endpoint, and other descriptors) 1827 * . high speed config ... all descriptors, for high speed operation; 1828 * this one's optional except for high-speed hardware 1829 * . device descriptor 1830 * 1831 * Endpoints are not yet enabled. Drivers must wait until device 1832 * configuration and interface altsetting changes create 1833 * the need to configure (or unconfigure) them. 1834 * 1835 * After initialization, the device stays active for as long as that 1836 * $CHIP file is open. Events must then be read from that descriptor, 1837 * such as configuration notifications. 1838 */ 1839 1840static int is_valid_config (struct usb_config_descriptor *config) 1841{ 1842 return config->bDescriptorType == USB_DT_CONFIG 1843 && config->bLength == USB_DT_CONFIG_SIZE 1844 && config->bConfigurationValue != 0 1845 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0 1846 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0; 1847 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */ 1848 /* FIXME check lengths: walk to end */ 1849} 1850 1851static ssize_t 1852dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 1853{ 1854 struct dev_data *dev = fd->private_data; 1855 ssize_t value = len, length = len; 1856 unsigned total; 1857 u32 tag; 1858 char *kbuf; 1859 1860 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) 1861 return -EINVAL; 1862 1863 /* we might need to change message format someday */ 1864 if (copy_from_user (&tag, buf, 4)) 1865 return -EFAULT; 1866 if (tag != 0) 1867 return -EINVAL; 1868 buf += 4; 1869 length -= 4; 1870 1871 kbuf = kmalloc (length, GFP_KERNEL); 1872 if (!kbuf) 1873 return -ENOMEM; 1874 if (copy_from_user (kbuf, buf, length)) { 1875 kfree (kbuf); 1876 return -EFAULT; 1877 } 1878 1879 spin_lock_irq (&dev->lock); 1880 value = -EINVAL; 1881 if (dev->buf) 1882 goto fail; 1883 dev->buf = kbuf; 1884 1885 /* full or low speed config */ 1886 dev->config = (void *) kbuf; 1887 total = le16_to_cpup (&dev->config->wTotalLength); 1888 if (!is_valid_config (dev->config) || total >= length) 1889 goto fail; 1890 kbuf += total; 1891 length -= total; 1892 1893 /* optional high speed config */ 1894 if (kbuf [1] == USB_DT_CONFIG) { 1895 dev->hs_config = (void *) kbuf; 1896 total = le16_to_cpup (&dev->hs_config->wTotalLength); 1897 if (!is_valid_config (dev->hs_config) || total >= length) 1898 goto fail; 1899 kbuf += total; 1900 length -= total; 1901 } 1902 1903 /* could support multiple configs, using another encoding! */ 1904 1905 /* device descriptor (tweaked for paranoia) */ 1906 if (length != USB_DT_DEVICE_SIZE) 1907 goto fail; 1908 dev->dev = (void *)kbuf; 1909 if (dev->dev->bLength != USB_DT_DEVICE_SIZE 1910 || dev->dev->bDescriptorType != USB_DT_DEVICE 1911 || dev->dev->bNumConfigurations != 1) 1912 goto fail; 1913 dev->dev->bNumConfigurations = 1; 1914 dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200); 1915 1916 /* triggers gadgetfs_bind(); then we can enumerate. */ 1917 spin_unlock_irq (&dev->lock); 1918 value = usb_gadget_register_driver (&gadgetfs_driver); 1919 if (value != 0) { 1920 kfree (dev->buf); 1921 dev->buf = NULL; 1922 } else { 1923 /* at this point "good" hardware has for the first time 1924 * let the USB the host see us. alternatively, if users 1925 * unplug/replug that will clear all the error state. 1926 * 1927 * note: everything running before here was guaranteed 1928 * to choke driver model style diagnostics. from here 1929 * on, they can work ... except in cleanup paths that 1930 * kick in after the ep0 descriptor is closed. 1931 */ 1932 fd->f_op = &ep0_io_operations; 1933 value = len; 1934 } 1935 return value; 1936 1937fail: 1938 spin_unlock_irq (&dev->lock); 1939 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev); 1940 kfree (dev->buf); 1941 dev->buf = NULL; 1942 return value; 1943} 1944 1945static int 1946dev_open (struct inode *inode, struct file *fd) 1947{ 1948 struct dev_data *dev = inode->i_private; 1949 int value = -EBUSY; 1950 1951 spin_lock_irq(&dev->lock); 1952 if (dev->state == STATE_DEV_DISABLED) { 1953 dev->ev_next = 0; 1954 dev->state = STATE_DEV_OPENED; 1955 fd->private_data = dev; 1956 get_dev (dev); 1957 value = 0; 1958 } 1959 spin_unlock_irq(&dev->lock); 1960 return value; 1961} 1962 1963static const struct file_operations dev_init_operations = { 1964 .owner = THIS_MODULE, 1965 .llseek = no_llseek, 1966 1967 .open = dev_open, 1968 .write = dev_config, 1969 .fasync = ep0_fasync, 1970 .ioctl = dev_ioctl, 1971 .release = dev_release, 1972}; 1973 1974/*----------------------------------------------------------------------*/ 1975 1976/* FILESYSTEM AND SUPERBLOCK OPERATIONS 1977 * 1978 * Mounting the filesystem creates a controller file, used first for 1979 * device configuration then later for event monitoring. 1980 */ 1981 1982 1983/* FIXME PAM etc could set this security policy without mount options 1984 * if epfiles inherited ownership and permissons from ep0 ... 1985 */ 1986 1987static unsigned default_uid; 1988static unsigned default_gid; 1989static unsigned default_perm = S_IRUSR | S_IWUSR; 1990 1991module_param (default_uid, uint, 0644); 1992module_param (default_gid, uint, 0644); 1993module_param (default_perm, uint, 0644); 1994 1995 1996static struct inode * 1997gadgetfs_make_inode (struct super_block *sb, 1998 void *data, const struct file_operations *fops, 1999 int mode) 2000{ 2001 struct inode *inode = new_inode (sb); 2002 2003 if (inode) { 2004 inode->i_mode = mode; 2005 inode->i_uid = default_uid; 2006 inode->i_gid = default_gid; 2007 inode->i_blocks = 0; 2008 inode->i_atime = inode->i_mtime = inode->i_ctime 2009 = CURRENT_TIME; 2010 inode->i_private = data; 2011 inode->i_fop = fops; 2012 } 2013 return inode; 2014} 2015 2016/* creates in fs root directory, so non-renamable and non-linkable. 2017 * so inode and dentry are paired, until device reconfig. 2018 */ 2019static struct inode * 2020gadgetfs_create_file (struct super_block *sb, char const *name, 2021 void *data, const struct file_operations *fops, 2022 struct dentry **dentry_p) 2023{ 2024 struct dentry *dentry; 2025 struct inode *inode; 2026 2027 dentry = d_alloc_name(sb->s_root, name); 2028 if (!dentry) 2029 return NULL; 2030 2031 inode = gadgetfs_make_inode (sb, data, fops, 2032 S_IFREG | (default_perm & S_IRWXUGO)); 2033 if (!inode) { 2034 dput(dentry); 2035 return NULL; 2036 } 2037 d_add (dentry, inode); 2038 *dentry_p = dentry; 2039 return inode; 2040} 2041 2042static struct super_operations gadget_fs_operations = { 2043 .statfs = simple_statfs, 2044 .drop_inode = generic_delete_inode, 2045}; 2046 2047static int 2048gadgetfs_fill_super (struct super_block *sb, void *opts, int silent) 2049{ 2050 struct inode *inode; 2051 struct dentry *d; 2052 struct dev_data *dev; 2053 2054 if (the_device) 2055 return -ESRCH; 2056 2057 /* fake probe to determine $CHIP */ 2058 (void) usb_gadget_register_driver (&probe_driver); 2059 if (!CHIP) 2060 return -ENODEV; 2061 2062 /* superblock */ 2063 sb->s_blocksize = PAGE_CACHE_SIZE; 2064 sb->s_blocksize_bits = PAGE_CACHE_SHIFT; 2065 sb->s_magic = GADGETFS_MAGIC; 2066 sb->s_op = &gadget_fs_operations; 2067 sb->s_time_gran = 1; 2068 2069 /* root inode */ 2070 inode = gadgetfs_make_inode (sb, 2071 NULL, &simple_dir_operations, 2072 S_IFDIR | S_IRUGO | S_IXUGO); 2073 if (!inode) 2074 goto enomem0; 2075 inode->i_op = &simple_dir_inode_operations; 2076 if (!(d = d_alloc_root (inode))) 2077 goto enomem1; 2078 sb->s_root = d; 2079 2080 /* the ep0 file is named after the controller we expect; 2081 * user mode code can use it for sanity checks, like we do. 2082 */ 2083 dev = dev_new (); 2084 if (!dev) 2085 goto enomem2; 2086 2087 dev->sb = sb; 2088 if (!gadgetfs_create_file (sb, CHIP, 2089 dev, &dev_init_operations, 2090 &dev->dentry)) 2091 goto enomem3; 2092 2093 /* other endpoint files are available after hardware setup, 2094 * from binding to a controller. 2095 */ 2096 the_device = dev; 2097 return 0; 2098 2099enomem3: 2100 put_dev (dev); 2101enomem2: 2102 dput (d); 2103enomem1: 2104 iput (inode); 2105enomem0: 2106 return -ENOMEM; 2107} 2108 2109/* "mount -t gadgetfs path /dev/gadget" ends up here */ 2110static int 2111gadgetfs_get_sb (struct file_system_type *t, int flags, 2112 const char *path, void *opts, struct vfsmount *mnt) 2113{ 2114 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt); 2115} 2116 2117static void 2118gadgetfs_kill_sb (struct super_block *sb) 2119{ 2120 kill_litter_super (sb); 2121 if (the_device) { 2122 put_dev (the_device); 2123 the_device = NULL; 2124 } 2125} 2126 2127/*----------------------------------------------------------------------*/ 2128 2129static struct file_system_type gadgetfs_type = { 2130 .owner = THIS_MODULE, 2131 .name = shortname, 2132 .get_sb = gadgetfs_get_sb, 2133 .kill_sb = gadgetfs_kill_sb, 2134}; 2135 2136/*----------------------------------------------------------------------*/ 2137 2138static int __init init (void) 2139{ 2140 int status; 2141 2142 status = register_filesystem (&gadgetfs_type); 2143 if (status == 0) 2144 pr_info ("%s: %s, version " DRIVER_VERSION "\n", 2145 shortname, driver_desc); 2146 return status; 2147} 2148module_init (init); 2149 2150static void __exit cleanup (void) 2151{ 2152 pr_debug ("unregister %s\n", shortname); 2153 unregister_filesystem (&gadgetfs_type); 2154} 2155module_exit (cleanup); 2156 2157