inode.c revision 9454a57ab5922e5cd25321cae9d1a8cbeb3e2e85
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 VERBOSE_DEBUG */ 24 25#include <linux/init.h> 26#include <linux/module.h> 27#include <linux/fs.h> 28#include <linux/pagemap.h> 29#include <linux/uts.h> 30#include <linux/wait.h> 31#include <linux/compiler.h> 32#include <asm/uaccess.h> 33#include <linux/slab.h> 34#include <linux/poll.h> 35 36#include <linux/device.h> 37#include <linux/moduleparam.h> 38 39#include <linux/usb/gadgetfs.h> 40#include <linux/usb/gadget.h> 41 42 43/* 44 * The gadgetfs API maps each endpoint to a file descriptor so that you 45 * can use standard synchronous read/write calls for I/O. There's some 46 * O_NONBLOCK and O_ASYNC/FASYNC style i/o support. Example usermode 47 * drivers show how this works in practice. You can also use AIO to 48 * eliminate I/O gaps between requests, to help when streaming data. 49 * 50 * Key parts that must be USB-specific are protocols defining how the 51 * read/write operations relate to the hardware state machines. There 52 * are two types of files. One type is for the device, implementing ep0. 53 * The other type is for each IN or OUT endpoint. In both cases, the 54 * user mode driver must configure the hardware before using it. 55 * 56 * - First, dev_config() is called when /dev/gadget/$CHIP is configured 57 * (by writing configuration and device descriptors). Afterwards it 58 * may serve as a source of device events, used to handle all control 59 * requests other than basic enumeration. 60 * 61 * - Then, after a SET_CONFIGURATION control request, ep_config() is 62 * called when each /dev/gadget/ep* file is configured (by writing 63 * endpoint descriptors). Afterwards these files are used to write() 64 * IN data or to read() OUT data. To halt the endpoint, a "wrong 65 * direction" request is issued (like reading an IN endpoint). 66 * 67 * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe 68 * not possible on all hardware. For example, precise fault handling with 69 * respect to data left in endpoint fifos after aborted operations; or 70 * selective clearing of endpoint halts, to implement SET_INTERFACE. 71 */ 72 73#define DRIVER_DESC "USB Gadget filesystem" 74#define DRIVER_VERSION "24 Aug 2004" 75 76static const char driver_desc [] = DRIVER_DESC; 77static const char shortname [] = "gadgetfs"; 78 79MODULE_DESCRIPTION (DRIVER_DESC); 80MODULE_AUTHOR ("David Brownell"); 81MODULE_LICENSE ("GPL"); 82 83 84/*----------------------------------------------------------------------*/ 85 86#define GADGETFS_MAGIC 0xaee71ee7 87#define DMA_ADDR_INVALID (~(dma_addr_t)0) 88 89/* /dev/gadget/$CHIP represents ep0 and the whole device */ 90enum ep0_state { 91 /* DISBLED is the initial state. 92 */ 93 STATE_DEV_DISABLED = 0, 94 95 /* Only one open() of /dev/gadget/$CHIP; only one file tracks 96 * ep0/device i/o modes and binding to the controller. Driver 97 * must always write descriptors to initialize the device, then 98 * the device becomes UNCONNECTED until enumeration. 99 */ 100 STATE_DEV_OPENED, 101 102 /* From then on, ep0 fd is in either of two basic modes: 103 * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it 104 * - SETUP: read/write will transfer control data and succeed; 105 * or if "wrong direction", performs protocol stall 106 */ 107 STATE_DEV_UNCONNECTED, 108 STATE_DEV_CONNECTED, 109 STATE_DEV_SETUP, 110 111 /* UNBOUND means the driver closed ep0, so the device won't be 112 * accessible again (DEV_DISABLED) until all fds are closed. 113 */ 114 STATE_DEV_UNBOUND, 115}; 116 117/* enough for the whole queue: most events invalidate others */ 118#define N_EVENT 5 119 120struct dev_data { 121 spinlock_t lock; 122 atomic_t count; 123 enum ep0_state state; /* P: lock */ 124 struct usb_gadgetfs_event event [N_EVENT]; 125 unsigned ev_next; 126 struct fasync_struct *fasync; 127 u8 current_config; 128 129 /* drivers reading ep0 MUST handle control requests (SETUP) 130 * reported that way; else the host will time out. 131 */ 132 unsigned usermode_setup : 1, 133 setup_in : 1, 134 setup_can_stall : 1, 135 setup_out_ready : 1, 136 setup_out_error : 1, 137 setup_abort : 1; 138 unsigned setup_wLength; 139 140 /* the rest is basically write-once */ 141 struct usb_config_descriptor *config, *hs_config; 142 struct usb_device_descriptor *dev; 143 struct usb_request *req; 144 struct usb_gadget *gadget; 145 struct list_head epfiles; 146 void *buf; 147 wait_queue_head_t wait; 148 struct super_block *sb; 149 struct dentry *dentry; 150 151 /* except this scratch i/o buffer for ep0 */ 152 u8 rbuf [256]; 153}; 154 155static inline void get_dev (struct dev_data *data) 156{ 157 atomic_inc (&data->count); 158} 159 160static void put_dev (struct dev_data *data) 161{ 162 if (likely (!atomic_dec_and_test (&data->count))) 163 return; 164 /* needs no more cleanup */ 165 BUG_ON (waitqueue_active (&data->wait)); 166 kfree (data); 167} 168 169static struct dev_data *dev_new (void) 170{ 171 struct dev_data *dev; 172 173 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 174 if (!dev) 175 return NULL; 176 dev->state = STATE_DEV_DISABLED; 177 atomic_set (&dev->count, 1); 178 spin_lock_init (&dev->lock); 179 INIT_LIST_HEAD (&dev->epfiles); 180 init_waitqueue_head (&dev->wait); 181 return dev; 182} 183 184/*----------------------------------------------------------------------*/ 185 186/* other /dev/gadget/$ENDPOINT files represent endpoints */ 187enum ep_state { 188 STATE_EP_DISABLED = 0, 189 STATE_EP_READY, 190 STATE_EP_ENABLED, 191 STATE_EP_UNBOUND, 192}; 193 194struct ep_data { 195 struct semaphore lock; 196 enum ep_state state; 197 atomic_t count; 198 struct dev_data *dev; 199 /* must hold dev->lock before accessing ep or req */ 200 struct usb_ep *ep; 201 struct usb_request *req; 202 ssize_t status; 203 char name [16]; 204 struct usb_endpoint_descriptor desc, hs_desc; 205 struct list_head epfiles; 206 wait_queue_head_t wait; 207 struct dentry *dentry; 208 struct inode *inode; 209}; 210 211static inline void get_ep (struct ep_data *data) 212{ 213 atomic_inc (&data->count); 214} 215 216static void put_ep (struct ep_data *data) 217{ 218 if (likely (!atomic_dec_and_test (&data->count))) 219 return; 220 put_dev (data->dev); 221 /* needs no more cleanup */ 222 BUG_ON (!list_empty (&data->epfiles)); 223 BUG_ON (waitqueue_active (&data->wait)); 224 kfree (data); 225} 226 227/*----------------------------------------------------------------------*/ 228 229/* most "how to use the hardware" policy choices are in userspace: 230 * mapping endpoint roles (which the driver needs) to the capabilities 231 * which the usb controller has. most of those capabilities are exposed 232 * implicitly, starting with the driver name and then endpoint names. 233 */ 234 235static const char *CHIP; 236 237/*----------------------------------------------------------------------*/ 238 239/* NOTE: don't use dev_printk calls before binding to the gadget 240 * at the end of ep0 configuration, or after unbind. 241 */ 242 243/* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */ 244#define xprintk(d,level,fmt,args...) \ 245 printk(level "%s: " fmt , shortname , ## args) 246 247#ifdef DEBUG 248#define DBG(dev,fmt,args...) \ 249 xprintk(dev , KERN_DEBUG , fmt , ## args) 250#else 251#define DBG(dev,fmt,args...) \ 252 do { } while (0) 253#endif /* DEBUG */ 254 255#ifdef VERBOSE_DEBUG 256#define VDEBUG DBG 257#else 258#define VDEBUG(dev,fmt,args...) \ 259 do { } while (0) 260#endif /* DEBUG */ 261 262#define ERROR(dev,fmt,args...) \ 263 xprintk(dev , KERN_ERR , fmt , ## args) 264#define WARN(dev,fmt,args...) \ 265 xprintk(dev , KERN_WARNING , fmt , ## args) 266#define INFO(dev,fmt,args...) \ 267 xprintk(dev , KERN_INFO , fmt , ## args) 268 269 270/*----------------------------------------------------------------------*/ 271 272/* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso) 273 * 274 * After opening, configure non-control endpoints. Then use normal 275 * stream read() and write() requests; and maybe ioctl() to get more 276 * precise FIFO status when recovering from cancellation. 277 */ 278 279static void epio_complete (struct usb_ep *ep, struct usb_request *req) 280{ 281 struct ep_data *epdata = ep->driver_data; 282 283 if (!req->context) 284 return; 285 if (req->status) 286 epdata->status = req->status; 287 else 288 epdata->status = req->actual; 289 complete ((struct completion *)req->context); 290} 291 292/* tasklock endpoint, returning when it's connected. 293 * still need dev->lock to use epdata->ep. 294 */ 295static int 296get_ready_ep (unsigned f_flags, struct ep_data *epdata) 297{ 298 int val; 299 300 if (f_flags & O_NONBLOCK) { 301 if (down_trylock (&epdata->lock) != 0) 302 goto nonblock; 303 if (epdata->state != STATE_EP_ENABLED) { 304 up (&epdata->lock); 305nonblock: 306 val = -EAGAIN; 307 } else 308 val = 0; 309 return val; 310 } 311 312 if ((val = down_interruptible (&epdata->lock)) < 0) 313 return val; 314 315 switch (epdata->state) { 316 case STATE_EP_ENABLED: 317 break; 318 // case STATE_EP_DISABLED: /* "can't happen" */ 319 // case STATE_EP_READY: /* "can't happen" */ 320 default: /* error! */ 321 pr_debug ("%s: ep %p not available, state %d\n", 322 shortname, epdata, epdata->state); 323 // FALLTHROUGH 324 case STATE_EP_UNBOUND: /* clean disconnect */ 325 val = -ENODEV; 326 up (&epdata->lock); 327 } 328 return val; 329} 330 331static ssize_t 332ep_io (struct ep_data *epdata, void *buf, unsigned len) 333{ 334 DECLARE_COMPLETION_ONSTACK (done); 335 int value; 336 337 spin_lock_irq (&epdata->dev->lock); 338 if (likely (epdata->ep != NULL)) { 339 struct usb_request *req = epdata->req; 340 341 req->context = &done; 342 req->complete = epio_complete; 343 req->buf = buf; 344 req->length = len; 345 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC); 346 } else 347 value = -ENODEV; 348 spin_unlock_irq (&epdata->dev->lock); 349 350 if (likely (value == 0)) { 351 value = wait_event_interruptible (done.wait, done.done); 352 if (value != 0) { 353 spin_lock_irq (&epdata->dev->lock); 354 if (likely (epdata->ep != NULL)) { 355 DBG (epdata->dev, "%s i/o interrupted\n", 356 epdata->name); 357 usb_ep_dequeue (epdata->ep, epdata->req); 358 spin_unlock_irq (&epdata->dev->lock); 359 360 wait_event (done.wait, done.done); 361 if (epdata->status == -ECONNRESET) 362 epdata->status = -EINTR; 363 } else { 364 spin_unlock_irq (&epdata->dev->lock); 365 366 DBG (epdata->dev, "endpoint gone\n"); 367 epdata->status = -ENODEV; 368 } 369 } 370 return epdata->status; 371 } 372 return value; 373} 374 375 376/* handle a synchronous OUT bulk/intr/iso transfer */ 377static ssize_t 378ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr) 379{ 380 struct ep_data *data = fd->private_data; 381 void *kbuf; 382 ssize_t value; 383 384 if ((value = get_ready_ep (fd->f_flags, data)) < 0) 385 return value; 386 387 /* halt any endpoint by doing a "wrong direction" i/o call */ 388 if (data->desc.bEndpointAddress & USB_DIR_IN) { 389 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) 390 == USB_ENDPOINT_XFER_ISOC) 391 return -EINVAL; 392 DBG (data->dev, "%s halt\n", data->name); 393 spin_lock_irq (&data->dev->lock); 394 if (likely (data->ep != NULL)) 395 usb_ep_set_halt (data->ep); 396 spin_unlock_irq (&data->dev->lock); 397 up (&data->lock); 398 return -EBADMSG; 399 } 400 401 /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */ 402 403 value = -ENOMEM; 404 kbuf = kmalloc (len, GFP_KERNEL); 405 if (unlikely (!kbuf)) 406 goto free1; 407 408 value = ep_io (data, kbuf, len); 409 VDEBUG (data->dev, "%s read %zu OUT, status %d\n", 410 data->name, len, (int) value); 411 if (value >= 0 && copy_to_user (buf, kbuf, value)) 412 value = -EFAULT; 413 414free1: 415 up (&data->lock); 416 kfree (kbuf); 417 return value; 418} 419 420/* handle a synchronous IN bulk/intr/iso transfer */ 421static ssize_t 422ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 423{ 424 struct ep_data *data = fd->private_data; 425 void *kbuf; 426 ssize_t value; 427 428 if ((value = get_ready_ep (fd->f_flags, data)) < 0) 429 return value; 430 431 /* halt any endpoint by doing a "wrong direction" i/o call */ 432 if (!(data->desc.bEndpointAddress & USB_DIR_IN)) { 433 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) 434 == USB_ENDPOINT_XFER_ISOC) 435 return -EINVAL; 436 DBG (data->dev, "%s halt\n", data->name); 437 spin_lock_irq (&data->dev->lock); 438 if (likely (data->ep != NULL)) 439 usb_ep_set_halt (data->ep); 440 spin_unlock_irq (&data->dev->lock); 441 up (&data->lock); 442 return -EBADMSG; 443 } 444 445 /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */ 446 447 value = -ENOMEM; 448 kbuf = kmalloc (len, GFP_KERNEL); 449 if (!kbuf) 450 goto free1; 451 if (copy_from_user (kbuf, buf, len)) { 452 value = -EFAULT; 453 goto free1; 454 } 455 456 value = ep_io (data, kbuf, len); 457 VDEBUG (data->dev, "%s write %zu IN, status %d\n", 458 data->name, len, (int) value); 459free1: 460 up (&data->lock); 461 kfree (kbuf); 462 return value; 463} 464 465static int 466ep_release (struct inode *inode, struct file *fd) 467{ 468 struct ep_data *data = fd->private_data; 469 int value; 470 471 if ((value = down_interruptible(&data->lock)) < 0) 472 return value; 473 474 /* clean up if this can be reopened */ 475 if (data->state != STATE_EP_UNBOUND) { 476 data->state = STATE_EP_DISABLED; 477 data->desc.bDescriptorType = 0; 478 data->hs_desc.bDescriptorType = 0; 479 usb_ep_disable(data->ep); 480 } 481 up (&data->lock); 482 put_ep (data); 483 return 0; 484} 485 486static int ep_ioctl (struct inode *inode, struct file *fd, 487 unsigned code, unsigned long value) 488{ 489 struct ep_data *data = fd->private_data; 490 int status; 491 492 if ((status = get_ready_ep (fd->f_flags, data)) < 0) 493 return status; 494 495 spin_lock_irq (&data->dev->lock); 496 if (likely (data->ep != NULL)) { 497 switch (code) { 498 case GADGETFS_FIFO_STATUS: 499 status = usb_ep_fifo_status (data->ep); 500 break; 501 case GADGETFS_FIFO_FLUSH: 502 usb_ep_fifo_flush (data->ep); 503 break; 504 case GADGETFS_CLEAR_HALT: 505 status = usb_ep_clear_halt (data->ep); 506 break; 507 default: 508 status = -ENOTTY; 509 } 510 } else 511 status = -ENODEV; 512 spin_unlock_irq (&data->dev->lock); 513 up (&data->lock); 514 return status; 515} 516 517/*----------------------------------------------------------------------*/ 518 519/* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */ 520 521struct kiocb_priv { 522 struct usb_request *req; 523 struct ep_data *epdata; 524 void *buf; 525 const struct iovec *iv; 526 unsigned long nr_segs; 527 unsigned actual; 528}; 529 530static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e) 531{ 532 struct kiocb_priv *priv = iocb->private; 533 struct ep_data *epdata; 534 int value; 535 536 local_irq_disable(); 537 epdata = priv->epdata; 538 // spin_lock(&epdata->dev->lock); 539 kiocbSetCancelled(iocb); 540 if (likely(epdata && epdata->ep && priv->req)) 541 value = usb_ep_dequeue (epdata->ep, priv->req); 542 else 543 value = -EINVAL; 544 // spin_unlock(&epdata->dev->lock); 545 local_irq_enable(); 546 547 aio_put_req(iocb); 548 return value; 549} 550 551static ssize_t ep_aio_read_retry(struct kiocb *iocb) 552{ 553 struct kiocb_priv *priv = iocb->private; 554 ssize_t len, total; 555 void *to_copy; 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 to_copy = priv->buf; 564 for (i=0; i < priv->nr_segs; i++) { 565 ssize_t this = min((ssize_t)(priv->iv[i].iov_len), total); 566 567 if (copy_to_user(priv->iv[i].iov_base, to_copy, this)) { 568 if (len == 0) 569 len = -EFAULT; 570 break; 571 } 572 573 total -= this; 574 len += this; 575 to_copy += this; 576 if (total == 0) 577 break; 578 } 579 kfree(priv->buf); 580 kfree(priv); 581 return len; 582} 583 584static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req) 585{ 586 struct kiocb *iocb = req->context; 587 struct kiocb_priv *priv = iocb->private; 588 struct ep_data *epdata = priv->epdata; 589 590 /* lock against disconnect (and ideally, cancel) */ 591 spin_lock(&epdata->dev->lock); 592 priv->req = NULL; 593 priv->epdata = NULL; 594 595 /* if this was a write or a read returning no data then we 596 * don't need to copy anything to userspace, so we can 597 * complete the aio request immediately. 598 */ 599 if (priv->iv == NULL || unlikely(req->actual == 0)) { 600 kfree(req->buf); 601 kfree(priv); 602 iocb->private = NULL; 603 /* aio_complete() reports bytes-transferred _and_ faults */ 604 aio_complete(iocb, 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 kfree(req->buf); 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 = kmalloc(len, GFP_ATOMIC); 966 if (req->buf == NULL) { 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 1013 if (gadget_is_dualspeed(dev->gadget) 1014 && (dev->gadget->speed 1015 == USB_SPEED_HIGH)) 1016 power = dev->hs_config->bMaxPower; 1017 else 1018 power = dev->config->bMaxPower; 1019 usb_gadget_vbus_draw(dev->gadget, 2 * power); 1020 } 1021 1022 } else { /* collect OUT data */ 1023 if ((fd->f_flags & O_NONBLOCK) != 0 1024 && !dev->setup_out_ready) { 1025 retval = -EAGAIN; 1026 goto done; 1027 } 1028 spin_unlock_irq (&dev->lock); 1029 retval = wait_event_interruptible (dev->wait, 1030 dev->setup_out_ready != 0); 1031 1032 /* FIXME state could change from under us */ 1033 spin_lock_irq (&dev->lock); 1034 if (retval) 1035 goto done; 1036 1037 if (dev->state != STATE_DEV_SETUP) { 1038 retval = -ECANCELED; 1039 goto done; 1040 } 1041 dev->state = STATE_DEV_CONNECTED; 1042 1043 if (dev->setup_out_error) 1044 retval = -EIO; 1045 else { 1046 len = min (len, (size_t)dev->req->actual); 1047// FIXME don't call this with the spinlock held ... 1048 if (copy_to_user (buf, dev->req->buf, len)) 1049 retval = -EFAULT; 1050 clean_req (dev->gadget->ep0, dev->req); 1051 /* NOTE userspace can't yet choose to stall */ 1052 } 1053 } 1054 goto done; 1055 } 1056 1057 /* else normal: return event data */ 1058 if (len < sizeof dev->event [0]) { 1059 retval = -EINVAL; 1060 goto done; 1061 } 1062 len -= len % sizeof (struct usb_gadgetfs_event); 1063 dev->usermode_setup = 1; 1064 1065scan: 1066 /* return queued events right away */ 1067 if (dev->ev_next != 0) { 1068 unsigned i, n; 1069 1070 n = len / sizeof (struct usb_gadgetfs_event); 1071 if (dev->ev_next < n) 1072 n = dev->ev_next; 1073 1074 /* ep0 i/o has special semantics during STATE_DEV_SETUP */ 1075 for (i = 0; i < n; i++) { 1076 if (dev->event [i].type == GADGETFS_SETUP) { 1077 dev->state = STATE_DEV_SETUP; 1078 n = i + 1; 1079 break; 1080 } 1081 } 1082 spin_unlock_irq (&dev->lock); 1083 len = n * sizeof (struct usb_gadgetfs_event); 1084 if (copy_to_user (buf, &dev->event, len)) 1085 retval = -EFAULT; 1086 else 1087 retval = len; 1088 if (len > 0) { 1089 /* NOTE this doesn't guard against broken drivers; 1090 * concurrent ep0 readers may lose events. 1091 */ 1092 spin_lock_irq (&dev->lock); 1093 if (dev->ev_next > n) { 1094 memmove(&dev->event[0], &dev->event[n], 1095 sizeof (struct usb_gadgetfs_event) 1096 * (dev->ev_next - n)); 1097 } 1098 dev->ev_next -= n; 1099 spin_unlock_irq (&dev->lock); 1100 } 1101 return retval; 1102 } 1103 if (fd->f_flags & O_NONBLOCK) { 1104 retval = -EAGAIN; 1105 goto done; 1106 } 1107 1108 switch (state) { 1109 default: 1110 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state); 1111 retval = -ESRCH; 1112 break; 1113 case STATE_DEV_UNCONNECTED: 1114 case STATE_DEV_CONNECTED: 1115 spin_unlock_irq (&dev->lock); 1116 DBG (dev, "%s wait\n", __FUNCTION__); 1117 1118 /* wait for events */ 1119 retval = wait_event_interruptible (dev->wait, 1120 dev->ev_next != 0); 1121 if (retval < 0) 1122 return retval; 1123 spin_lock_irq (&dev->lock); 1124 goto scan; 1125 } 1126 1127done: 1128 spin_unlock_irq (&dev->lock); 1129 return retval; 1130} 1131 1132static struct usb_gadgetfs_event * 1133next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type) 1134{ 1135 struct usb_gadgetfs_event *event; 1136 unsigned i; 1137 1138 switch (type) { 1139 /* these events purge the queue */ 1140 case GADGETFS_DISCONNECT: 1141 if (dev->state == STATE_DEV_SETUP) 1142 dev->setup_abort = 1; 1143 // FALL THROUGH 1144 case GADGETFS_CONNECT: 1145 dev->ev_next = 0; 1146 break; 1147 case GADGETFS_SETUP: /* previous request timed out */ 1148 case GADGETFS_SUSPEND: /* same effect */ 1149 /* these events can't be repeated */ 1150 for (i = 0; i != dev->ev_next; i++) { 1151 if (dev->event [i].type != type) 1152 continue; 1153 DBG(dev, "discard old event[%d] %d\n", i, type); 1154 dev->ev_next--; 1155 if (i == dev->ev_next) 1156 break; 1157 /* indices start at zero, for simplicity */ 1158 memmove (&dev->event [i], &dev->event [i + 1], 1159 sizeof (struct usb_gadgetfs_event) 1160 * (dev->ev_next - i)); 1161 } 1162 break; 1163 default: 1164 BUG (); 1165 } 1166 VDEBUG(dev, "event[%d] = %d\n", dev->ev_next, type); 1167 event = &dev->event [dev->ev_next++]; 1168 BUG_ON (dev->ev_next > N_EVENT); 1169 memset (event, 0, sizeof *event); 1170 event->type = type; 1171 return event; 1172} 1173 1174static ssize_t 1175ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 1176{ 1177 struct dev_data *dev = fd->private_data; 1178 ssize_t retval = -ESRCH; 1179 1180 spin_lock_irq (&dev->lock); 1181 1182 /* report fd mode change before acting on it */ 1183 if (dev->setup_abort) { 1184 dev->setup_abort = 0; 1185 retval = -EIDRM; 1186 1187 /* data and/or status stage for control request */ 1188 } else if (dev->state == STATE_DEV_SETUP) { 1189 1190 /* IN DATA+STATUS caller makes len <= wLength */ 1191 if (dev->setup_in) { 1192 retval = setup_req (dev->gadget->ep0, dev->req, len); 1193 if (retval == 0) { 1194 dev->state = STATE_DEV_CONNECTED; 1195 spin_unlock_irq (&dev->lock); 1196 if (copy_from_user (dev->req->buf, buf, len)) 1197 retval = -EFAULT; 1198 else { 1199 if (len < dev->setup_wLength) 1200 dev->req->zero = 1; 1201 retval = usb_ep_queue ( 1202 dev->gadget->ep0, dev->req, 1203 GFP_KERNEL); 1204 } 1205 if (retval < 0) { 1206 spin_lock_irq (&dev->lock); 1207 clean_req (dev->gadget->ep0, dev->req); 1208 spin_unlock_irq (&dev->lock); 1209 } else 1210 retval = len; 1211 1212 return retval; 1213 } 1214 1215 /* can stall some OUT transfers */ 1216 } else if (dev->setup_can_stall) { 1217 VDEBUG(dev, "ep0out stall\n"); 1218 (void) usb_ep_set_halt (dev->gadget->ep0); 1219 retval = -EL2HLT; 1220 dev->state = STATE_DEV_CONNECTED; 1221 } else { 1222 DBG(dev, "bogus ep0out stall!\n"); 1223 } 1224 } else 1225 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state); 1226 1227 spin_unlock_irq (&dev->lock); 1228 return retval; 1229} 1230 1231static int 1232ep0_fasync (int f, struct file *fd, int on) 1233{ 1234 struct dev_data *dev = fd->private_data; 1235 // caller must F_SETOWN before signal delivery happens 1236 VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off"); 1237 return fasync_helper (f, fd, on, &dev->fasync); 1238} 1239 1240static struct usb_gadget_driver gadgetfs_driver; 1241 1242static int 1243dev_release (struct inode *inode, struct file *fd) 1244{ 1245 struct dev_data *dev = fd->private_data; 1246 1247 /* closing ep0 === shutdown all */ 1248 1249 usb_gadget_unregister_driver (&gadgetfs_driver); 1250 1251 /* at this point "good" hardware has disconnected the 1252 * device from USB; the host won't see it any more. 1253 * alternatively, all host requests will time out. 1254 */ 1255 1256 fasync_helper (-1, fd, 0, &dev->fasync); 1257 kfree (dev->buf); 1258 dev->buf = NULL; 1259 put_dev (dev); 1260 1261 /* other endpoints were all decoupled from this device */ 1262 spin_lock_irq(&dev->lock); 1263 dev->state = STATE_DEV_DISABLED; 1264 spin_unlock_irq(&dev->lock); 1265 return 0; 1266} 1267 1268static unsigned int 1269ep0_poll (struct file *fd, poll_table *wait) 1270{ 1271 struct dev_data *dev = fd->private_data; 1272 int mask = 0; 1273 1274 poll_wait(fd, &dev->wait, wait); 1275 1276 spin_lock_irq (&dev->lock); 1277 1278 /* report fd mode change before acting on it */ 1279 if (dev->setup_abort) { 1280 dev->setup_abort = 0; 1281 mask = POLLHUP; 1282 goto out; 1283 } 1284 1285 if (dev->state == STATE_DEV_SETUP) { 1286 if (dev->setup_in || dev->setup_can_stall) 1287 mask = POLLOUT; 1288 } else { 1289 if (dev->ev_next != 0) 1290 mask = POLLIN; 1291 } 1292out: 1293 spin_unlock_irq(&dev->lock); 1294 return mask; 1295} 1296 1297static int dev_ioctl (struct inode *inode, struct file *fd, 1298 unsigned code, unsigned long value) 1299{ 1300 struct dev_data *dev = fd->private_data; 1301 struct usb_gadget *gadget = dev->gadget; 1302 1303 if (gadget->ops->ioctl) 1304 return gadget->ops->ioctl (gadget, code, value); 1305 return -ENOTTY; 1306} 1307 1308/* used after device configuration */ 1309static const struct file_operations ep0_io_operations = { 1310 .owner = THIS_MODULE, 1311 .llseek = no_llseek, 1312 1313 .read = ep0_read, 1314 .write = ep0_write, 1315 .fasync = ep0_fasync, 1316 .poll = ep0_poll, 1317 .ioctl = dev_ioctl, 1318 .release = dev_release, 1319}; 1320 1321/*----------------------------------------------------------------------*/ 1322 1323/* The in-kernel gadget driver handles most ep0 issues, in particular 1324 * enumerating the single configuration (as provided from user space). 1325 * 1326 * Unrecognized ep0 requests may be handled in user space. 1327 */ 1328 1329#ifdef CONFIG_USB_GADGET_DUALSPEED 1330static void make_qualifier (struct dev_data *dev) 1331{ 1332 struct usb_qualifier_descriptor qual; 1333 struct usb_device_descriptor *desc; 1334 1335 qual.bLength = sizeof qual; 1336 qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER; 1337 qual.bcdUSB = __constant_cpu_to_le16 (0x0200); 1338 1339 desc = dev->dev; 1340 qual.bDeviceClass = desc->bDeviceClass; 1341 qual.bDeviceSubClass = desc->bDeviceSubClass; 1342 qual.bDeviceProtocol = desc->bDeviceProtocol; 1343 1344 /* assumes ep0 uses the same value for both speeds ... */ 1345 qual.bMaxPacketSize0 = desc->bMaxPacketSize0; 1346 1347 qual.bNumConfigurations = 1; 1348 qual.bRESERVED = 0; 1349 1350 memcpy (dev->rbuf, &qual, sizeof qual); 1351} 1352#endif 1353 1354static int 1355config_buf (struct dev_data *dev, u8 type, unsigned index) 1356{ 1357 int len; 1358 int hs = 0; 1359 1360 /* only one configuration */ 1361 if (index > 0) 1362 return -EINVAL; 1363 1364 if (gadget_is_dualspeed(dev->gadget)) { 1365 hs = (dev->gadget->speed == USB_SPEED_HIGH); 1366 if (type == USB_DT_OTHER_SPEED_CONFIG) 1367 hs = !hs; 1368 } 1369 if (hs) { 1370 dev->req->buf = dev->hs_config; 1371 len = le16_to_cpu(dev->hs_config->wTotalLength); 1372 } else { 1373 dev->req->buf = dev->config; 1374 len = le16_to_cpu(dev->config->wTotalLength); 1375 } 1376 ((u8 *)dev->req->buf) [1] = type; 1377 return len; 1378} 1379 1380static int 1381gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl) 1382{ 1383 struct dev_data *dev = get_gadget_data (gadget); 1384 struct usb_request *req = dev->req; 1385 int value = -EOPNOTSUPP; 1386 struct usb_gadgetfs_event *event; 1387 u16 w_value = le16_to_cpu(ctrl->wValue); 1388 u16 w_length = le16_to_cpu(ctrl->wLength); 1389 1390 spin_lock (&dev->lock); 1391 dev->setup_abort = 0; 1392 if (dev->state == STATE_DEV_UNCONNECTED) { 1393 if (gadget_is_dualspeed(gadget) 1394 && gadget->speed == USB_SPEED_HIGH 1395 && dev->hs_config == NULL) { 1396 spin_unlock(&dev->lock); 1397 ERROR (dev, "no high speed config??\n"); 1398 return -EINVAL; 1399 } 1400 1401 dev->state = STATE_DEV_CONNECTED; 1402 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket; 1403 1404 INFO (dev, "connected\n"); 1405 event = next_event (dev, GADGETFS_CONNECT); 1406 event->u.speed = gadget->speed; 1407 ep0_readable (dev); 1408 1409 /* host may have given up waiting for response. we can miss control 1410 * requests handled lower down (device/endpoint status and features); 1411 * then ep0_{read,write} will report the wrong status. controller 1412 * driver will have aborted pending i/o. 1413 */ 1414 } else if (dev->state == STATE_DEV_SETUP) 1415 dev->setup_abort = 1; 1416 1417 req->buf = dev->rbuf; 1418 req->dma = DMA_ADDR_INVALID; 1419 req->context = NULL; 1420 value = -EOPNOTSUPP; 1421 switch (ctrl->bRequest) { 1422 1423 case USB_REQ_GET_DESCRIPTOR: 1424 if (ctrl->bRequestType != USB_DIR_IN) 1425 goto unrecognized; 1426 switch (w_value >> 8) { 1427 1428 case USB_DT_DEVICE: 1429 value = min (w_length, (u16) sizeof *dev->dev); 1430 req->buf = dev->dev; 1431 break; 1432#ifdef CONFIG_USB_GADGET_DUALSPEED 1433 case USB_DT_DEVICE_QUALIFIER: 1434 if (!dev->hs_config) 1435 break; 1436 value = min (w_length, (u16) 1437 sizeof (struct usb_qualifier_descriptor)); 1438 make_qualifier (dev); 1439 break; 1440 case USB_DT_OTHER_SPEED_CONFIG: 1441 // FALLTHROUGH 1442#endif 1443 case USB_DT_CONFIG: 1444 value = config_buf (dev, 1445 w_value >> 8, 1446 w_value & 0xff); 1447 if (value >= 0) 1448 value = min (w_length, (u16) value); 1449 break; 1450 case USB_DT_STRING: 1451 goto unrecognized; 1452 1453 default: // all others are errors 1454 break; 1455 } 1456 break; 1457 1458 /* currently one config, two speeds */ 1459 case USB_REQ_SET_CONFIGURATION: 1460 if (ctrl->bRequestType != 0) 1461 break; 1462 if (0 == (u8) w_value) { 1463 value = 0; 1464 dev->current_config = 0; 1465 usb_gadget_vbus_draw(gadget, 8 /* mA */ ); 1466 // user mode expected to disable endpoints 1467 } else { 1468 u8 config, power; 1469 1470 if (gadget_is_dualspeed(gadget) 1471 && gadget->speed == USB_SPEED_HIGH) { 1472 config = dev->hs_config->bConfigurationValue; 1473 power = dev->hs_config->bMaxPower; 1474 } else { 1475 config = dev->config->bConfigurationValue; 1476 power = dev->config->bMaxPower; 1477 } 1478 1479 if (config == (u8) w_value) { 1480 value = 0; 1481 dev->current_config = config; 1482 usb_gadget_vbus_draw(gadget, 2 * power); 1483 } 1484 } 1485 1486 /* report SET_CONFIGURATION like any other control request, 1487 * except that usermode may not stall this. the next 1488 * request mustn't be allowed start until this finishes: 1489 * endpoints and threads set up, etc. 1490 * 1491 * NOTE: older PXA hardware (before PXA 255: without UDCCFR) 1492 * has bad/racey automagic that prevents synchronizing here. 1493 * even kernel mode drivers often miss them. 1494 */ 1495 if (value == 0) { 1496 INFO (dev, "configuration #%d\n", dev->current_config); 1497 if (dev->usermode_setup) { 1498 dev->setup_can_stall = 0; 1499 goto delegate; 1500 } 1501 } 1502 break; 1503 1504#ifndef CONFIG_USB_GADGET_PXA2XX 1505 /* PXA automagically handles this request too */ 1506 case USB_REQ_GET_CONFIGURATION: 1507 if (ctrl->bRequestType != 0x80) 1508 break; 1509 *(u8 *)req->buf = dev->current_config; 1510 value = min (w_length, (u16) 1); 1511 break; 1512#endif 1513 1514 default: 1515unrecognized: 1516 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n", 1517 dev->usermode_setup ? "delegate" : "fail", 1518 ctrl->bRequestType, ctrl->bRequest, 1519 w_value, le16_to_cpu(ctrl->wIndex), w_length); 1520 1521 /* if there's an ep0 reader, don't stall */ 1522 if (dev->usermode_setup) { 1523 dev->setup_can_stall = 1; 1524delegate: 1525 dev->setup_in = (ctrl->bRequestType & USB_DIR_IN) 1526 ? 1 : 0; 1527 dev->setup_wLength = w_length; 1528 dev->setup_out_ready = 0; 1529 dev->setup_out_error = 0; 1530 value = 0; 1531 1532 /* read DATA stage for OUT right away */ 1533 if (unlikely (!dev->setup_in && w_length)) { 1534 value = setup_req (gadget->ep0, dev->req, 1535 w_length); 1536 if (value < 0) 1537 break; 1538 value = usb_ep_queue (gadget->ep0, dev->req, 1539 GFP_ATOMIC); 1540 if (value < 0) { 1541 clean_req (gadget->ep0, dev->req); 1542 break; 1543 } 1544 1545 /* we can't currently stall these */ 1546 dev->setup_can_stall = 0; 1547 } 1548 1549 /* state changes when reader collects event */ 1550 event = next_event (dev, GADGETFS_SETUP); 1551 event->u.setup = *ctrl; 1552 ep0_readable (dev); 1553 spin_unlock (&dev->lock); 1554 return 0; 1555 } 1556 } 1557 1558 /* proceed with data transfer and status phases? */ 1559 if (value >= 0 && dev->state != STATE_DEV_SETUP) { 1560 req->length = value; 1561 req->zero = value < w_length; 1562 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC); 1563 if (value < 0) { 1564 DBG (dev, "ep_queue --> %d\n", value); 1565 req->status = 0; 1566 } 1567 } 1568 1569 /* device stalls when value < 0 */ 1570 spin_unlock (&dev->lock); 1571 return value; 1572} 1573 1574static void destroy_ep_files (struct dev_data *dev) 1575{ 1576 struct list_head *entry, *tmp; 1577 1578 DBG (dev, "%s %d\n", __FUNCTION__, dev->state); 1579 1580 /* dev->state must prevent interference */ 1581restart: 1582 spin_lock_irq (&dev->lock); 1583 list_for_each_safe (entry, tmp, &dev->epfiles) { 1584 struct ep_data *ep; 1585 struct inode *parent; 1586 struct dentry *dentry; 1587 1588 /* break link to FS */ 1589 ep = list_entry (entry, struct ep_data, epfiles); 1590 list_del_init (&ep->epfiles); 1591 dentry = ep->dentry; 1592 ep->dentry = NULL; 1593 parent = dentry->d_parent->d_inode; 1594 1595 /* break link to controller */ 1596 if (ep->state == STATE_EP_ENABLED) 1597 (void) usb_ep_disable (ep->ep); 1598 ep->state = STATE_EP_UNBOUND; 1599 usb_ep_free_request (ep->ep, ep->req); 1600 ep->ep = NULL; 1601 wake_up (&ep->wait); 1602 put_ep (ep); 1603 1604 spin_unlock_irq (&dev->lock); 1605 1606 /* break link to dcache */ 1607 mutex_lock (&parent->i_mutex); 1608 d_delete (dentry); 1609 dput (dentry); 1610 mutex_unlock (&parent->i_mutex); 1611 1612 /* fds may still be open */ 1613 goto restart; 1614 } 1615 spin_unlock_irq (&dev->lock); 1616} 1617 1618 1619static struct inode * 1620gadgetfs_create_file (struct super_block *sb, char const *name, 1621 void *data, const struct file_operations *fops, 1622 struct dentry **dentry_p); 1623 1624static int activate_ep_files (struct dev_data *dev) 1625{ 1626 struct usb_ep *ep; 1627 struct ep_data *data; 1628 1629 gadget_for_each_ep (ep, dev->gadget) { 1630 1631 data = kzalloc(sizeof(*data), GFP_KERNEL); 1632 if (!data) 1633 goto enomem0; 1634 data->state = STATE_EP_DISABLED; 1635 init_MUTEX (&data->lock); 1636 init_waitqueue_head (&data->wait); 1637 1638 strncpy (data->name, ep->name, sizeof (data->name) - 1); 1639 atomic_set (&data->count, 1); 1640 data->dev = dev; 1641 get_dev (dev); 1642 1643 data->ep = ep; 1644 ep->driver_data = data; 1645 1646 data->req = usb_ep_alloc_request (ep, GFP_KERNEL); 1647 if (!data->req) 1648 goto enomem1; 1649 1650 data->inode = gadgetfs_create_file (dev->sb, data->name, 1651 data, &ep_config_operations, 1652 &data->dentry); 1653 if (!data->inode) 1654 goto enomem2; 1655 list_add_tail (&data->epfiles, &dev->epfiles); 1656 } 1657 return 0; 1658 1659enomem2: 1660 usb_ep_free_request (ep, data->req); 1661enomem1: 1662 put_dev (dev); 1663 kfree (data); 1664enomem0: 1665 DBG (dev, "%s enomem\n", __FUNCTION__); 1666 destroy_ep_files (dev); 1667 return -ENOMEM; 1668} 1669 1670static void 1671gadgetfs_unbind (struct usb_gadget *gadget) 1672{ 1673 struct dev_data *dev = get_gadget_data (gadget); 1674 1675 DBG (dev, "%s\n", __FUNCTION__); 1676 1677 spin_lock_irq (&dev->lock); 1678 dev->state = STATE_DEV_UNBOUND; 1679 spin_unlock_irq (&dev->lock); 1680 1681 destroy_ep_files (dev); 1682 gadget->ep0->driver_data = NULL; 1683 set_gadget_data (gadget, NULL); 1684 1685 /* we've already been disconnected ... no i/o is active */ 1686 if (dev->req) 1687 usb_ep_free_request (gadget->ep0, dev->req); 1688 DBG (dev, "%s done\n", __FUNCTION__); 1689 put_dev (dev); 1690} 1691 1692static struct dev_data *the_device; 1693 1694static int 1695gadgetfs_bind (struct usb_gadget *gadget) 1696{ 1697 struct dev_data *dev = the_device; 1698 1699 if (!dev) 1700 return -ESRCH; 1701 if (0 != strcmp (CHIP, gadget->name)) { 1702 printk (KERN_ERR "%s expected %s controller not %s\n", 1703 shortname, CHIP, gadget->name); 1704 return -ENODEV; 1705 } 1706 1707 set_gadget_data (gadget, dev); 1708 dev->gadget = gadget; 1709 gadget->ep0->driver_data = dev; 1710 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket; 1711 1712 /* preallocate control response and buffer */ 1713 dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL); 1714 if (!dev->req) 1715 goto enomem; 1716 dev->req->context = NULL; 1717 dev->req->complete = epio_complete; 1718 1719 if (activate_ep_files (dev) < 0) 1720 goto enomem; 1721 1722 INFO (dev, "bound to %s driver\n", gadget->name); 1723 spin_lock_irq(&dev->lock); 1724 dev->state = STATE_DEV_UNCONNECTED; 1725 spin_unlock_irq(&dev->lock); 1726 get_dev (dev); 1727 return 0; 1728 1729enomem: 1730 gadgetfs_unbind (gadget); 1731 return -ENOMEM; 1732} 1733 1734static void 1735gadgetfs_disconnect (struct usb_gadget *gadget) 1736{ 1737 struct dev_data *dev = get_gadget_data (gadget); 1738 1739 spin_lock (&dev->lock); 1740 if (dev->state == STATE_DEV_UNCONNECTED) 1741 goto exit; 1742 dev->state = STATE_DEV_UNCONNECTED; 1743 1744 INFO (dev, "disconnected\n"); 1745 next_event (dev, GADGETFS_DISCONNECT); 1746 ep0_readable (dev); 1747exit: 1748 spin_unlock (&dev->lock); 1749} 1750 1751static void 1752gadgetfs_suspend (struct usb_gadget *gadget) 1753{ 1754 struct dev_data *dev = get_gadget_data (gadget); 1755 1756 INFO (dev, "suspended from state %d\n", dev->state); 1757 spin_lock (&dev->lock); 1758 switch (dev->state) { 1759 case STATE_DEV_SETUP: // VERY odd... host died?? 1760 case STATE_DEV_CONNECTED: 1761 case STATE_DEV_UNCONNECTED: 1762 next_event (dev, GADGETFS_SUSPEND); 1763 ep0_readable (dev); 1764 /* FALLTHROUGH */ 1765 default: 1766 break; 1767 } 1768 spin_unlock (&dev->lock); 1769} 1770 1771static struct usb_gadget_driver gadgetfs_driver = { 1772#ifdef CONFIG_USB_GADGET_DUALSPEED 1773 .speed = USB_SPEED_HIGH, 1774#else 1775 .speed = USB_SPEED_FULL, 1776#endif 1777 .function = (char *) driver_desc, 1778 .bind = gadgetfs_bind, 1779 .unbind = gadgetfs_unbind, 1780 .setup = gadgetfs_setup, 1781 .disconnect = gadgetfs_disconnect, 1782 .suspend = gadgetfs_suspend, 1783 1784 .driver = { 1785 .name = (char *) shortname, 1786 }, 1787}; 1788 1789/*----------------------------------------------------------------------*/ 1790 1791static void gadgetfs_nop(struct usb_gadget *arg) { } 1792 1793static int gadgetfs_probe (struct usb_gadget *gadget) 1794{ 1795 CHIP = gadget->name; 1796 return -EISNAM; 1797} 1798 1799static struct usb_gadget_driver probe_driver = { 1800 .speed = USB_SPEED_HIGH, 1801 .bind = gadgetfs_probe, 1802 .unbind = gadgetfs_nop, 1803 .setup = (void *)gadgetfs_nop, 1804 .disconnect = gadgetfs_nop, 1805 .driver = { 1806 .name = "nop", 1807 }, 1808}; 1809 1810 1811/* DEVICE INITIALIZATION 1812 * 1813 * fd = open ("/dev/gadget/$CHIP", O_RDWR) 1814 * status = write (fd, descriptors, sizeof descriptors) 1815 * 1816 * That write establishes the device configuration, so the kernel can 1817 * bind to the controller ... guaranteeing it can handle enumeration 1818 * at all necessary speeds. Descriptor order is: 1819 * 1820 * . message tag (u32, host order) ... for now, must be zero; it 1821 * would change to support features like multi-config devices 1822 * . full/low speed config ... all wTotalLength bytes (with interface, 1823 * class, altsetting, endpoint, and other descriptors) 1824 * . high speed config ... all descriptors, for high speed operation; 1825 * this one's optional except for high-speed hardware 1826 * . device descriptor 1827 * 1828 * Endpoints are not yet enabled. Drivers must wait until device 1829 * configuration and interface altsetting changes create 1830 * the need to configure (or unconfigure) them. 1831 * 1832 * After initialization, the device stays active for as long as that 1833 * $CHIP file is open. Events must then be read from that descriptor, 1834 * such as configuration notifications. 1835 */ 1836 1837static int is_valid_config (struct usb_config_descriptor *config) 1838{ 1839 return config->bDescriptorType == USB_DT_CONFIG 1840 && config->bLength == USB_DT_CONFIG_SIZE 1841 && config->bConfigurationValue != 0 1842 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0 1843 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0; 1844 /* FIXME if gadget->is_otg, _must_ include an otg descriptor */ 1845 /* FIXME check lengths: walk to end */ 1846} 1847 1848static ssize_t 1849dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr) 1850{ 1851 struct dev_data *dev = fd->private_data; 1852 ssize_t value = len, length = len; 1853 unsigned total; 1854 u32 tag; 1855 char *kbuf; 1856 1857 if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4)) 1858 return -EINVAL; 1859 1860 /* we might need to change message format someday */ 1861 if (copy_from_user (&tag, buf, 4)) 1862 return -EFAULT; 1863 if (tag != 0) 1864 return -EINVAL; 1865 buf += 4; 1866 length -= 4; 1867 1868 kbuf = kmalloc (length, GFP_KERNEL); 1869 if (!kbuf) 1870 return -ENOMEM; 1871 if (copy_from_user (kbuf, buf, length)) { 1872 kfree (kbuf); 1873 return -EFAULT; 1874 } 1875 1876 spin_lock_irq (&dev->lock); 1877 value = -EINVAL; 1878 if (dev->buf) 1879 goto fail; 1880 dev->buf = kbuf; 1881 1882 /* full or low speed config */ 1883 dev->config = (void *) kbuf; 1884 total = le16_to_cpu(dev->config->wTotalLength); 1885 if (!is_valid_config (dev->config) || total >= length) 1886 goto fail; 1887 kbuf += total; 1888 length -= total; 1889 1890 /* optional high speed config */ 1891 if (kbuf [1] == USB_DT_CONFIG) { 1892 dev->hs_config = (void *) kbuf; 1893 total = le16_to_cpu(dev->hs_config->wTotalLength); 1894 if (!is_valid_config (dev->hs_config) || total >= length) 1895 goto fail; 1896 kbuf += total; 1897 length -= total; 1898 } 1899 1900 /* could support multiple configs, using another encoding! */ 1901 1902 /* device descriptor (tweaked for paranoia) */ 1903 if (length != USB_DT_DEVICE_SIZE) 1904 goto fail; 1905 dev->dev = (void *)kbuf; 1906 if (dev->dev->bLength != USB_DT_DEVICE_SIZE 1907 || dev->dev->bDescriptorType != USB_DT_DEVICE 1908 || dev->dev->bNumConfigurations != 1) 1909 goto fail; 1910 dev->dev->bNumConfigurations = 1; 1911 dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200); 1912 1913 /* triggers gadgetfs_bind(); then we can enumerate. */ 1914 spin_unlock_irq (&dev->lock); 1915 value = usb_gadget_register_driver (&gadgetfs_driver); 1916 if (value != 0) { 1917 kfree (dev->buf); 1918 dev->buf = NULL; 1919 } else { 1920 /* at this point "good" hardware has for the first time 1921 * let the USB the host see us. alternatively, if users 1922 * unplug/replug that will clear all the error state. 1923 * 1924 * note: everything running before here was guaranteed 1925 * to choke driver model style diagnostics. from here 1926 * on, they can work ... except in cleanup paths that 1927 * kick in after the ep0 descriptor is closed. 1928 */ 1929 fd->f_op = &ep0_io_operations; 1930 value = len; 1931 } 1932 return value; 1933 1934fail: 1935 spin_unlock_irq (&dev->lock); 1936 pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev); 1937 kfree (dev->buf); 1938 dev->buf = NULL; 1939 return value; 1940} 1941 1942static int 1943dev_open (struct inode *inode, struct file *fd) 1944{ 1945 struct dev_data *dev = inode->i_private; 1946 int value = -EBUSY; 1947 1948 spin_lock_irq(&dev->lock); 1949 if (dev->state == STATE_DEV_DISABLED) { 1950 dev->ev_next = 0; 1951 dev->state = STATE_DEV_OPENED; 1952 fd->private_data = dev; 1953 get_dev (dev); 1954 value = 0; 1955 } 1956 spin_unlock_irq(&dev->lock); 1957 return value; 1958} 1959 1960static const struct file_operations dev_init_operations = { 1961 .owner = THIS_MODULE, 1962 .llseek = no_llseek, 1963 1964 .open = dev_open, 1965 .write = dev_config, 1966 .fasync = ep0_fasync, 1967 .ioctl = dev_ioctl, 1968 .release = dev_release, 1969}; 1970 1971/*----------------------------------------------------------------------*/ 1972 1973/* FILESYSTEM AND SUPERBLOCK OPERATIONS 1974 * 1975 * Mounting the filesystem creates a controller file, used first for 1976 * device configuration then later for event monitoring. 1977 */ 1978 1979 1980/* FIXME PAM etc could set this security policy without mount options 1981 * if epfiles inherited ownership and permissons from ep0 ... 1982 */ 1983 1984static unsigned default_uid; 1985static unsigned default_gid; 1986static unsigned default_perm = S_IRUSR | S_IWUSR; 1987 1988module_param (default_uid, uint, 0644); 1989module_param (default_gid, uint, 0644); 1990module_param (default_perm, uint, 0644); 1991 1992 1993static struct inode * 1994gadgetfs_make_inode (struct super_block *sb, 1995 void *data, const struct file_operations *fops, 1996 int mode) 1997{ 1998 struct inode *inode = new_inode (sb); 1999 2000 if (inode) { 2001 inode->i_mode = mode; 2002 inode->i_uid = default_uid; 2003 inode->i_gid = default_gid; 2004 inode->i_blocks = 0; 2005 inode->i_atime = inode->i_mtime = inode->i_ctime 2006 = CURRENT_TIME; 2007 inode->i_private = data; 2008 inode->i_fop = fops; 2009 } 2010 return inode; 2011} 2012 2013/* creates in fs root directory, so non-renamable and non-linkable. 2014 * so inode and dentry are paired, until device reconfig. 2015 */ 2016static struct inode * 2017gadgetfs_create_file (struct super_block *sb, char const *name, 2018 void *data, const struct file_operations *fops, 2019 struct dentry **dentry_p) 2020{ 2021 struct dentry *dentry; 2022 struct inode *inode; 2023 2024 dentry = d_alloc_name(sb->s_root, name); 2025 if (!dentry) 2026 return NULL; 2027 2028 inode = gadgetfs_make_inode (sb, data, fops, 2029 S_IFREG | (default_perm & S_IRWXUGO)); 2030 if (!inode) { 2031 dput(dentry); 2032 return NULL; 2033 } 2034 d_add (dentry, inode); 2035 *dentry_p = dentry; 2036 return inode; 2037} 2038 2039static struct super_operations gadget_fs_operations = { 2040 .statfs = simple_statfs, 2041 .drop_inode = generic_delete_inode, 2042}; 2043 2044static int 2045gadgetfs_fill_super (struct super_block *sb, void *opts, int silent) 2046{ 2047 struct inode *inode; 2048 struct dentry *d; 2049 struct dev_data *dev; 2050 2051 if (the_device) 2052 return -ESRCH; 2053 2054 /* fake probe to determine $CHIP */ 2055 (void) usb_gadget_register_driver (&probe_driver); 2056 if (!CHIP) 2057 return -ENODEV; 2058 2059 /* superblock */ 2060 sb->s_blocksize = PAGE_CACHE_SIZE; 2061 sb->s_blocksize_bits = PAGE_CACHE_SHIFT; 2062 sb->s_magic = GADGETFS_MAGIC; 2063 sb->s_op = &gadget_fs_operations; 2064 sb->s_time_gran = 1; 2065 2066 /* root inode */ 2067 inode = gadgetfs_make_inode (sb, 2068 NULL, &simple_dir_operations, 2069 S_IFDIR | S_IRUGO | S_IXUGO); 2070 if (!inode) 2071 goto enomem0; 2072 inode->i_op = &simple_dir_inode_operations; 2073 if (!(d = d_alloc_root (inode))) 2074 goto enomem1; 2075 sb->s_root = d; 2076 2077 /* the ep0 file is named after the controller we expect; 2078 * user mode code can use it for sanity checks, like we do. 2079 */ 2080 dev = dev_new (); 2081 if (!dev) 2082 goto enomem2; 2083 2084 dev->sb = sb; 2085 if (!gadgetfs_create_file (sb, CHIP, 2086 dev, &dev_init_operations, 2087 &dev->dentry)) 2088 goto enomem3; 2089 2090 /* other endpoint files are available after hardware setup, 2091 * from binding to a controller. 2092 */ 2093 the_device = dev; 2094 return 0; 2095 2096enomem3: 2097 put_dev (dev); 2098enomem2: 2099 dput (d); 2100enomem1: 2101 iput (inode); 2102enomem0: 2103 return -ENOMEM; 2104} 2105 2106/* "mount -t gadgetfs path /dev/gadget" ends up here */ 2107static int 2108gadgetfs_get_sb (struct file_system_type *t, int flags, 2109 const char *path, void *opts, struct vfsmount *mnt) 2110{ 2111 return get_sb_single (t, flags, opts, gadgetfs_fill_super, mnt); 2112} 2113 2114static void 2115gadgetfs_kill_sb (struct super_block *sb) 2116{ 2117 kill_litter_super (sb); 2118 if (the_device) { 2119 put_dev (the_device); 2120 the_device = NULL; 2121 } 2122} 2123 2124/*----------------------------------------------------------------------*/ 2125 2126static struct file_system_type gadgetfs_type = { 2127 .owner = THIS_MODULE, 2128 .name = shortname, 2129 .get_sb = gadgetfs_get_sb, 2130 .kill_sb = gadgetfs_kill_sb, 2131}; 2132 2133/*----------------------------------------------------------------------*/ 2134 2135static int __init init (void) 2136{ 2137 int status; 2138 2139 status = register_filesystem (&gadgetfs_type); 2140 if (status == 0) 2141 pr_info ("%s: %s, version " DRIVER_VERSION "\n", 2142 shortname, driver_desc); 2143 return status; 2144} 2145module_init (init); 2146 2147static void __exit cleanup (void) 2148{ 2149 pr_debug ("unregister %s\n", shortname); 2150 unregister_filesystem (&gadgetfs_type); 2151} 2152module_exit (cleanup); 2153 2154