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v4.6
 
   1/*
   2 * WUSB Wire Adapter
   3 * Data transfer and URB enqueing
   4 *
   5 * Copyright (C) 2005-2006 Intel Corporation
   6 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   7 *
   8 * This program is free software; you can redistribute it and/or
   9 * modify it under the terms of the GNU General Public License version
  10 * 2 as published by the Free Software Foundation.
  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., 51 Franklin Street, Fifth Floor, Boston, MA
  20 * 02110-1301, USA.
  21 *
  22 *
  23 * How transfers work: get a buffer, break it up in segments (segment
  24 * size is a multiple of the maxpacket size). For each segment issue a
  25 * segment request (struct wa_xfer_*), then send the data buffer if
  26 * out or nothing if in (all over the DTO endpoint).
  27 *
  28 * For each submitted segment request, a notification will come over
  29 * the NEP endpoint and a transfer result (struct xfer_result) will
  30 * arrive in the DTI URB. Read it, get the xfer ID, see if there is
  31 * data coming (inbound transfer), schedule a read and handle it.
  32 *
  33 * Sounds simple, it is a pain to implement.
  34 *
  35 *
  36 * ENTRY POINTS
  37 *
  38 *   FIXME
  39 *
  40 * LIFE CYCLE / STATE DIAGRAM
  41 *
  42 *   FIXME
  43 *
  44 * THIS CODE IS DISGUSTING
  45 *
  46 *   Warned you are; it's my second try and still not happy with it.
  47 *
  48 * NOTES:
  49 *
  50 *   - No iso
  51 *
  52 *   - Supports DMA xfers, control, bulk and maybe interrupt
  53 *
  54 *   - Does not recycle unused rpipes
  55 *
  56 *     An rpipe is assigned to an endpoint the first time it is used,
  57 *     and then it's there, assigned, until the endpoint is disabled
  58 *     (destroyed [{h,d}wahc_op_ep_disable()]. The assignment of the
  59 *     rpipe to the endpoint is done under the wa->rpipe_sem semaphore
  60 *     (should be a mutex).
  61 *
  62 *     Two methods it could be done:
  63 *
  64 *     (a) set up a timer every time an rpipe's use count drops to 1
  65 *         (which means unused) or when a transfer ends. Reset the
  66 *         timer when a xfer is queued. If the timer expires, release
  67 *         the rpipe [see rpipe_ep_disable()].
  68 *
  69 *     (b) when looking for free rpipes to attach [rpipe_get_by_ep()],
  70 *         when none are found go over the list, check their endpoint
  71 *         and their activity record (if no last-xfer-done-ts in the
  72 *         last x seconds) take it
  73 *
  74 *     However, due to the fact that we have a set of limited
  75 *     resources (max-segments-at-the-same-time per xfer,
  76 *     xfers-per-ripe, blocks-per-rpipe, rpipes-per-host), at the end
  77 *     we are going to have to rebuild all this based on an scheduler,
  78 *     to where we have a list of transactions to do and based on the
  79 *     availability of the different required components (blocks,
  80 *     rpipes, segment slots, etc), we go scheduling them. Painful.
  81 */
  82#include <linux/spinlock.h>
  83#include <linux/slab.h>
  84#include <linux/hash.h>
  85#include <linux/ratelimit.h>
  86#include <linux/export.h>
  87#include <linux/scatterlist.h>
  88
  89#include "wa-hc.h"
  90#include "wusbhc.h"
  91
  92enum {
  93	/* [WUSB] section 8.3.3 allocates 7 bits for the segment index. */
  94	WA_SEGS_MAX = 128,
  95};
  96
  97enum wa_seg_status {
  98	WA_SEG_NOTREADY,
  99	WA_SEG_READY,
 100	WA_SEG_DELAYED,
 101	WA_SEG_SUBMITTED,
 102	WA_SEG_PENDING,
 103	WA_SEG_DTI_PENDING,
 104	WA_SEG_DONE,
 105	WA_SEG_ERROR,
 106	WA_SEG_ABORTED,
 107};
 108
 109static void wa_xfer_delayed_run(struct wa_rpipe *);
 110static int __wa_xfer_delayed_run(struct wa_rpipe *rpipe, int *dto_waiting);
 111
 112/*
 113 * Life cycle governed by 'struct urb' (the refcount of the struct is
 114 * that of the 'struct urb' and usb_free_urb() would free the whole
 115 * struct).
 116 */
 117struct wa_seg {
 118	struct urb tr_urb;		/* transfer request urb. */
 119	struct urb *isoc_pack_desc_urb;	/* for isoc packet descriptor. */
 120	struct urb *dto_urb;		/* for data output. */
 121	struct list_head list_node;	/* for rpipe->req_list */
 122	struct wa_xfer *xfer;		/* out xfer */
 123	u8 index;			/* which segment we are */
 124	int isoc_frame_count;	/* number of isoc frames in this segment. */
 125	int isoc_frame_offset;	/* starting frame offset in the xfer URB. */
 126	/* Isoc frame that the current transfer buffer corresponds to. */
 127	int isoc_frame_index;
 128	int isoc_size;	/* size of all isoc frames sent by this seg. */
 129	enum wa_seg_status status;
 130	ssize_t result;			/* bytes xfered or error */
 131	struct wa_xfer_hdr xfer_hdr;
 132};
 133
 134static inline void wa_seg_init(struct wa_seg *seg)
 135{
 136	usb_init_urb(&seg->tr_urb);
 137
 138	/* set the remaining memory to 0. */
 139	memset(((void *)seg) + sizeof(seg->tr_urb), 0,
 140		sizeof(*seg) - sizeof(seg->tr_urb));
 141}
 142
 143/*
 144 * Protected by xfer->lock
 145 *
 146 */
 147struct wa_xfer {
 148	struct kref refcnt;
 149	struct list_head list_node;
 150	spinlock_t lock;
 151	u32 id;
 152
 153	struct wahc *wa;		/* Wire adapter we are plugged to */
 154	struct usb_host_endpoint *ep;
 155	struct urb *urb;		/* URB we are transferring for */
 156	struct wa_seg **seg;		/* transfer segments */
 157	u8 segs, segs_submitted, segs_done;
 158	unsigned is_inbound:1;
 159	unsigned is_dma:1;
 160	size_t seg_size;
 161	int result;
 162
 163	gfp_t gfp;			/* allocation mask */
 164
 165	struct wusb_dev *wusb_dev;	/* for activity timestamps */
 166};
 167
 168static void __wa_populate_dto_urb_isoc(struct wa_xfer *xfer,
 169	struct wa_seg *seg, int curr_iso_frame);
 170static void wa_complete_remaining_xfer_segs(struct wa_xfer *xfer,
 171		int starting_index, enum wa_seg_status status);
 172
 173static inline void wa_xfer_init(struct wa_xfer *xfer)
 174{
 175	kref_init(&xfer->refcnt);
 176	INIT_LIST_HEAD(&xfer->list_node);
 177	spin_lock_init(&xfer->lock);
 178}
 179
 180/*
 181 * Destroy a transfer structure
 182 *
 183 * Note that freeing xfer->seg[cnt]->tr_urb will free the containing
 184 * xfer->seg[cnt] memory that was allocated by __wa_xfer_setup_segs.
 185 */
 186static void wa_xfer_destroy(struct kref *_xfer)
 187{
 188	struct wa_xfer *xfer = container_of(_xfer, struct wa_xfer, refcnt);
 189	if (xfer->seg) {
 190		unsigned cnt;
 191		for (cnt = 0; cnt < xfer->segs; cnt++) {
 192			struct wa_seg *seg = xfer->seg[cnt];
 193			if (seg) {
 194				usb_free_urb(seg->isoc_pack_desc_urb);
 195				if (seg->dto_urb) {
 196					kfree(seg->dto_urb->sg);
 197					usb_free_urb(seg->dto_urb);
 198				}
 199				usb_free_urb(&seg->tr_urb);
 200			}
 201		}
 202		kfree(xfer->seg);
 203	}
 204	kfree(xfer);
 205}
 206
 207static void wa_xfer_get(struct wa_xfer *xfer)
 208{
 209	kref_get(&xfer->refcnt);
 210}
 211
 212static void wa_xfer_put(struct wa_xfer *xfer)
 213{
 214	kref_put(&xfer->refcnt, wa_xfer_destroy);
 215}
 216
 217/*
 218 * Try to get exclusive access to the DTO endpoint resource.  Return true
 219 * if successful.
 220 */
 221static inline int __wa_dto_try_get(struct wahc *wa)
 222{
 223	return (test_and_set_bit(0, &wa->dto_in_use) == 0);
 224}
 225
 226/* Release the DTO endpoint resource. */
 227static inline void __wa_dto_put(struct wahc *wa)
 228{
 229	clear_bit_unlock(0, &wa->dto_in_use);
 230}
 231
 232/* Service RPIPEs that are waiting on the DTO resource. */
 233static void wa_check_for_delayed_rpipes(struct wahc *wa)
 234{
 235	unsigned long flags;
 236	int dto_waiting = 0;
 237	struct wa_rpipe *rpipe;
 238
 239	spin_lock_irqsave(&wa->rpipe_lock, flags);
 240	while (!list_empty(&wa->rpipe_delayed_list) && !dto_waiting) {
 241		rpipe = list_first_entry(&wa->rpipe_delayed_list,
 242				struct wa_rpipe, list_node);
 243		__wa_xfer_delayed_run(rpipe, &dto_waiting);
 244		/* remove this RPIPE from the list if it is not waiting. */
 245		if (!dto_waiting) {
 246			pr_debug("%s: RPIPE %d serviced and removed from delayed list.\n",
 247				__func__,
 248				le16_to_cpu(rpipe->descr.wRPipeIndex));
 249			list_del_init(&rpipe->list_node);
 250		}
 251	}
 252	spin_unlock_irqrestore(&wa->rpipe_lock, flags);
 253}
 254
 255/* add this RPIPE to the end of the delayed RPIPE list. */
 256static void wa_add_delayed_rpipe(struct wahc *wa, struct wa_rpipe *rpipe)
 257{
 258	unsigned long flags;
 259
 260	spin_lock_irqsave(&wa->rpipe_lock, flags);
 261	/* add rpipe to the list if it is not already on it. */
 262	if (list_empty(&rpipe->list_node)) {
 263		pr_debug("%s: adding RPIPE %d to the delayed list.\n",
 264			__func__, le16_to_cpu(rpipe->descr.wRPipeIndex));
 265		list_add_tail(&rpipe->list_node, &wa->rpipe_delayed_list);
 266	}
 267	spin_unlock_irqrestore(&wa->rpipe_lock, flags);
 268}
 269
 270/*
 271 * xfer is referenced
 272 *
 273 * xfer->lock has to be unlocked
 274 *
 275 * We take xfer->lock for setting the result; this is a barrier
 276 * against drivers/usb/core/hcd.c:unlink1() being called after we call
 277 * usb_hcd_giveback_urb() and wa_urb_dequeue() trying to get a
 278 * reference to the transfer.
 279 */
 280static void wa_xfer_giveback(struct wa_xfer *xfer)
 281{
 282	unsigned long flags;
 283
 284	spin_lock_irqsave(&xfer->wa->xfer_list_lock, flags);
 285	list_del_init(&xfer->list_node);
 286	usb_hcd_unlink_urb_from_ep(&(xfer->wa->wusb->usb_hcd), xfer->urb);
 287	spin_unlock_irqrestore(&xfer->wa->xfer_list_lock, flags);
 288	/* FIXME: segmentation broken -- kills DWA */
 289	wusbhc_giveback_urb(xfer->wa->wusb, xfer->urb, xfer->result);
 290	wa_put(xfer->wa);
 291	wa_xfer_put(xfer);
 292}
 293
 294/*
 295 * xfer is referenced
 296 *
 297 * xfer->lock has to be unlocked
 298 */
 299static void wa_xfer_completion(struct wa_xfer *xfer)
 300{
 301	if (xfer->wusb_dev)
 302		wusb_dev_put(xfer->wusb_dev);
 303	rpipe_put(xfer->ep->hcpriv);
 304	wa_xfer_giveback(xfer);
 305}
 306
 307/*
 308 * Initialize a transfer's ID
 309 *
 310 * We need to use a sequential number; if we use the pointer or the
 311 * hash of the pointer, it can repeat over sequential transfers and
 312 * then it will confuse the HWA....wonder why in hell they put a 32
 313 * bit handle in there then.
 314 */
 315static void wa_xfer_id_init(struct wa_xfer *xfer)
 316{
 317	xfer->id = atomic_add_return(1, &xfer->wa->xfer_id_count);
 318}
 319
 320/* Return the xfer's ID. */
 321static inline u32 wa_xfer_id(struct wa_xfer *xfer)
 322{
 323	return xfer->id;
 324}
 325
 326/* Return the xfer's ID in transport format (little endian). */
 327static inline __le32 wa_xfer_id_le32(struct wa_xfer *xfer)
 328{
 329	return cpu_to_le32(xfer->id);
 330}
 331
 332/*
 333 * If transfer is done, wrap it up and return true
 334 *
 335 * xfer->lock has to be locked
 336 */
 337static unsigned __wa_xfer_is_done(struct wa_xfer *xfer)
 338{
 339	struct device *dev = &xfer->wa->usb_iface->dev;
 340	unsigned result, cnt;
 341	struct wa_seg *seg;
 342	struct urb *urb = xfer->urb;
 343	unsigned found_short = 0;
 344
 345	result = xfer->segs_done == xfer->segs_submitted;
 346	if (result == 0)
 347		goto out;
 348	urb->actual_length = 0;
 349	for (cnt = 0; cnt < xfer->segs; cnt++) {
 350		seg = xfer->seg[cnt];
 351		switch (seg->status) {
 352		case WA_SEG_DONE:
 353			if (found_short && seg->result > 0) {
 354				dev_dbg(dev, "xfer %p ID %08X#%u: bad short segments (%zu)\n",
 355					xfer, wa_xfer_id(xfer), cnt,
 356					seg->result);
 357				urb->status = -EINVAL;
 358				goto out;
 359			}
 360			urb->actual_length += seg->result;
 361			if (!(usb_pipeisoc(xfer->urb->pipe))
 362				&& seg->result < xfer->seg_size
 363			    && cnt != xfer->segs-1)
 364				found_short = 1;
 365			dev_dbg(dev, "xfer %p ID %08X#%u: DONE short %d "
 366				"result %zu urb->actual_length %d\n",
 367				xfer, wa_xfer_id(xfer), seg->index, found_short,
 368				seg->result, urb->actual_length);
 369			break;
 370		case WA_SEG_ERROR:
 371			xfer->result = seg->result;
 372			dev_dbg(dev, "xfer %p ID %08X#%u: ERROR result %zi(0x%08zX)\n",
 373				xfer, wa_xfer_id(xfer), seg->index, seg->result,
 374				seg->result);
 375			goto out;
 376		case WA_SEG_ABORTED:
 377			xfer->result = seg->result;
 378			dev_dbg(dev, "xfer %p ID %08X#%u: ABORTED result %zi(0x%08zX)\n",
 379				xfer, wa_xfer_id(xfer), seg->index, seg->result,
 380				seg->result);
 381			goto out;
 382		default:
 383			dev_warn(dev, "xfer %p ID %08X#%u: is_done bad state %d\n",
 384				 xfer, wa_xfer_id(xfer), cnt, seg->status);
 385			xfer->result = -EINVAL;
 386			goto out;
 387		}
 388	}
 389	xfer->result = 0;
 390out:
 391	return result;
 392}
 393
 394/*
 395 * Mark the given segment as done.  Return true if this completes the xfer.
 396 * This should only be called for segs that have been submitted to an RPIPE.
 397 * Delayed segs are not marked as submitted so they do not need to be marked
 398 * as done when cleaning up.
 399 *
 400 * xfer->lock has to be locked
 401 */
 402static unsigned __wa_xfer_mark_seg_as_done(struct wa_xfer *xfer,
 403	struct wa_seg *seg, enum wa_seg_status status)
 404{
 405	seg->status = status;
 406	xfer->segs_done++;
 407
 408	/* check for done. */
 409	return __wa_xfer_is_done(xfer);
 410}
 411
 412/*
 413 * Search for a transfer list ID on the HCD's URB list
 414 *
 415 * For 32 bit architectures, we use the pointer itself; for 64 bits, a
 416 * 32-bit hash of the pointer.
 417 *
 418 * @returns NULL if not found.
 419 */
 420static struct wa_xfer *wa_xfer_get_by_id(struct wahc *wa, u32 id)
 421{
 422	unsigned long flags;
 423	struct wa_xfer *xfer_itr;
 424	spin_lock_irqsave(&wa->xfer_list_lock, flags);
 425	list_for_each_entry(xfer_itr, &wa->xfer_list, list_node) {
 426		if (id == xfer_itr->id) {
 427			wa_xfer_get(xfer_itr);
 428			goto out;
 429		}
 430	}
 431	xfer_itr = NULL;
 432out:
 433	spin_unlock_irqrestore(&wa->xfer_list_lock, flags);
 434	return xfer_itr;
 435}
 436
 437struct wa_xfer_abort_buffer {
 438	struct urb urb;
 439	struct wahc *wa;
 440	struct wa_xfer_abort cmd;
 441};
 442
 443static void __wa_xfer_abort_cb(struct urb *urb)
 444{
 445	struct wa_xfer_abort_buffer *b = urb->context;
 446	struct wahc *wa = b->wa;
 447
 448	/*
 449	 * If the abort request URB failed, then the HWA did not get the abort
 450	 * command.  Forcibly clean up the xfer without waiting for a Transfer
 451	 * Result from the HWA.
 452	 */
 453	if (urb->status < 0) {
 454		struct wa_xfer *xfer;
 455		struct device *dev = &wa->usb_iface->dev;
 456
 457		xfer = wa_xfer_get_by_id(wa, le32_to_cpu(b->cmd.dwTransferID));
 458		dev_err(dev, "%s: Transfer Abort request failed. result: %d\n",
 459			__func__, urb->status);
 460		if (xfer) {
 461			unsigned long flags;
 462			int done, seg_index = 0;
 463			struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 464
 465			dev_err(dev, "%s: cleaning up xfer %p ID 0x%08X.\n",
 466				__func__, xfer, wa_xfer_id(xfer));
 467			spin_lock_irqsave(&xfer->lock, flags);
 468			/* skip done segs. */
 469			while (seg_index < xfer->segs) {
 470				struct wa_seg *seg = xfer->seg[seg_index];
 471
 472				if ((seg->status == WA_SEG_DONE) ||
 473					(seg->status == WA_SEG_ERROR)) {
 474					++seg_index;
 475				} else {
 476					break;
 477				}
 478			}
 479			/* mark remaining segs as aborted. */
 480			wa_complete_remaining_xfer_segs(xfer, seg_index,
 481				WA_SEG_ABORTED);
 482			done = __wa_xfer_is_done(xfer);
 483			spin_unlock_irqrestore(&xfer->lock, flags);
 484			if (done)
 485				wa_xfer_completion(xfer);
 486			wa_xfer_delayed_run(rpipe);
 487			wa_xfer_put(xfer);
 488		} else {
 489			dev_err(dev, "%s: xfer ID 0x%08X already gone.\n",
 490				 __func__, le32_to_cpu(b->cmd.dwTransferID));
 491		}
 492	}
 493
 494	wa_put(wa);	/* taken in __wa_xfer_abort */
 495	usb_put_urb(&b->urb);
 496}
 497
 498/*
 499 * Aborts an ongoing transaction
 500 *
 501 * Assumes the transfer is referenced and locked and in a submitted
 502 * state (mainly that there is an endpoint/rpipe assigned).
 503 *
 504 * The callback (see above) does nothing but freeing up the data by
 505 * putting the URB. Because the URB is allocated at the head of the
 506 * struct, the whole space we allocated is kfreed. *
 507 */
 508static int __wa_xfer_abort(struct wa_xfer *xfer)
 509{
 510	int result = -ENOMEM;
 511	struct device *dev = &xfer->wa->usb_iface->dev;
 512	struct wa_xfer_abort_buffer *b;
 513	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 514
 515	b = kmalloc(sizeof(*b), GFP_ATOMIC);
 516	if (b == NULL)
 517		goto error_kmalloc;
 518	b->cmd.bLength =  sizeof(b->cmd);
 519	b->cmd.bRequestType = WA_XFER_ABORT;
 520	b->cmd.wRPipe = rpipe->descr.wRPipeIndex;
 521	b->cmd.dwTransferID = wa_xfer_id_le32(xfer);
 522	b->wa = wa_get(xfer->wa);
 523
 524	usb_init_urb(&b->urb);
 525	usb_fill_bulk_urb(&b->urb, xfer->wa->usb_dev,
 526		usb_sndbulkpipe(xfer->wa->usb_dev,
 527				xfer->wa->dto_epd->bEndpointAddress),
 528		&b->cmd, sizeof(b->cmd), __wa_xfer_abort_cb, b);
 529	result = usb_submit_urb(&b->urb, GFP_ATOMIC);
 530	if (result < 0)
 531		goto error_submit;
 532	return result;				/* callback frees! */
 533
 534
 535error_submit:
 536	wa_put(xfer->wa);
 537	if (printk_ratelimit())
 538		dev_err(dev, "xfer %p: Can't submit abort request: %d\n",
 539			xfer, result);
 540	kfree(b);
 541error_kmalloc:
 542	return result;
 543
 544}
 545
 546/*
 547 * Calculate the number of isoc frames starting from isoc_frame_offset
 548 * that will fit a in transfer segment.
 549 */
 550static int __wa_seg_calculate_isoc_frame_count(struct wa_xfer *xfer,
 551	int isoc_frame_offset, int *total_size)
 552{
 553	int segment_size = 0, frame_count = 0;
 554	int index = isoc_frame_offset;
 555	struct usb_iso_packet_descriptor *iso_frame_desc =
 556		xfer->urb->iso_frame_desc;
 557
 558	while ((index < xfer->urb->number_of_packets)
 559		&& ((segment_size + iso_frame_desc[index].length)
 560				<= xfer->seg_size)) {
 561		/*
 562		 * For Alereon HWA devices, only include an isoc frame in an
 563		 * out segment if it is physically contiguous with the previous
 564		 * frame.  This is required because those devices expect
 565		 * the isoc frames to be sent as a single USB transaction as
 566		 * opposed to one transaction per frame with standard HWA.
 567		 */
 568		if ((xfer->wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC)
 569			&& (xfer->is_inbound == 0)
 570			&& (index > isoc_frame_offset)
 571			&& ((iso_frame_desc[index - 1].offset +
 572				iso_frame_desc[index - 1].length) !=
 573				iso_frame_desc[index].offset))
 574			break;
 575
 576		/* this frame fits. count it. */
 577		++frame_count;
 578		segment_size += iso_frame_desc[index].length;
 579
 580		/* move to the next isoc frame. */
 581		++index;
 582	}
 583
 584	*total_size = segment_size;
 585	return frame_count;
 586}
 587
 588/*
 589 *
 590 * @returns < 0 on error, transfer segment request size if ok
 591 */
 592static ssize_t __wa_xfer_setup_sizes(struct wa_xfer *xfer,
 593				     enum wa_xfer_type *pxfer_type)
 594{
 595	ssize_t result;
 596	struct device *dev = &xfer->wa->usb_iface->dev;
 597	size_t maxpktsize;
 598	struct urb *urb = xfer->urb;
 599	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 600
 601	switch (rpipe->descr.bmAttribute & 0x3) {
 602	case USB_ENDPOINT_XFER_CONTROL:
 603		*pxfer_type = WA_XFER_TYPE_CTL;
 604		result = sizeof(struct wa_xfer_ctl);
 605		break;
 606	case USB_ENDPOINT_XFER_INT:
 607	case USB_ENDPOINT_XFER_BULK:
 608		*pxfer_type = WA_XFER_TYPE_BI;
 609		result = sizeof(struct wa_xfer_bi);
 610		break;
 611	case USB_ENDPOINT_XFER_ISOC:
 612		*pxfer_type = WA_XFER_TYPE_ISO;
 613		result = sizeof(struct wa_xfer_hwaiso);
 614		break;
 615	default:
 616		/* never happens */
 617		BUG();
 618		result = -EINVAL;	/* shut gcc up */
 619	}
 620	xfer->is_inbound = urb->pipe & USB_DIR_IN ? 1 : 0;
 621	xfer->is_dma = urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP ? 1 : 0;
 622
 623	maxpktsize = le16_to_cpu(rpipe->descr.wMaxPacketSize);
 624	xfer->seg_size = le16_to_cpu(rpipe->descr.wBlocks)
 625		* 1 << (xfer->wa->wa_descr->bRPipeBlockSize - 1);
 626	/* Compute the segment size and make sure it is a multiple of
 627	 * the maxpktsize (WUSB1.0[8.3.3.1])...not really too much of
 628	 * a check (FIXME) */
 629	if (xfer->seg_size < maxpktsize) {
 630		dev_err(dev,
 631			"HW BUG? seg_size %zu smaller than maxpktsize %zu\n",
 632			xfer->seg_size, maxpktsize);
 633		result = -EINVAL;
 634		goto error;
 635	}
 636	xfer->seg_size = (xfer->seg_size / maxpktsize) * maxpktsize;
 637	if ((rpipe->descr.bmAttribute & 0x3) == USB_ENDPOINT_XFER_ISOC) {
 638		int index = 0;
 639
 640		xfer->segs = 0;
 641		/*
 642		 * loop over urb->number_of_packets to determine how many
 643		 * xfer segments will be needed to send the isoc frames.
 644		 */
 645		while (index < urb->number_of_packets) {
 646			int seg_size; /* don't care. */
 647			index += __wa_seg_calculate_isoc_frame_count(xfer,
 648					index, &seg_size);
 649			++xfer->segs;
 650		}
 651	} else {
 652		xfer->segs = DIV_ROUND_UP(urb->transfer_buffer_length,
 653						xfer->seg_size);
 654		if (xfer->segs == 0 && *pxfer_type == WA_XFER_TYPE_CTL)
 655			xfer->segs = 1;
 656	}
 657
 658	if (xfer->segs > WA_SEGS_MAX) {
 659		dev_err(dev, "BUG? oops, number of segments %zu bigger than %d\n",
 660			(urb->transfer_buffer_length/xfer->seg_size),
 661			WA_SEGS_MAX);
 662		result = -EINVAL;
 663		goto error;
 664	}
 665error:
 666	return result;
 667}
 668
 669static void __wa_setup_isoc_packet_descr(
 670		struct wa_xfer_packet_info_hwaiso *packet_desc,
 671		struct wa_xfer *xfer,
 672		struct wa_seg *seg) {
 673	struct usb_iso_packet_descriptor *iso_frame_desc =
 674		xfer->urb->iso_frame_desc;
 675	int frame_index;
 676
 677	/* populate isoc packet descriptor. */
 678	packet_desc->bPacketType = WA_XFER_ISO_PACKET_INFO;
 679	packet_desc->wLength = cpu_to_le16(sizeof(*packet_desc) +
 680		(sizeof(packet_desc->PacketLength[0]) *
 681			seg->isoc_frame_count));
 682	for (frame_index = 0; frame_index < seg->isoc_frame_count;
 683		++frame_index) {
 684		int offset_index = frame_index + seg->isoc_frame_offset;
 685		packet_desc->PacketLength[frame_index] =
 686			cpu_to_le16(iso_frame_desc[offset_index].length);
 687	}
 688}
 689
 690
 691/* Fill in the common request header and xfer-type specific data. */
 692static void __wa_xfer_setup_hdr0(struct wa_xfer *xfer,
 693				 struct wa_xfer_hdr *xfer_hdr0,
 694				 enum wa_xfer_type xfer_type,
 695				 size_t xfer_hdr_size)
 696{
 697	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 698	struct wa_seg *seg = xfer->seg[0];
 699
 700	xfer_hdr0 = &seg->xfer_hdr;
 701	xfer_hdr0->bLength = xfer_hdr_size;
 702	xfer_hdr0->bRequestType = xfer_type;
 703	xfer_hdr0->wRPipe = rpipe->descr.wRPipeIndex;
 704	xfer_hdr0->dwTransferID = wa_xfer_id_le32(xfer);
 705	xfer_hdr0->bTransferSegment = 0;
 706	switch (xfer_type) {
 707	case WA_XFER_TYPE_CTL: {
 708		struct wa_xfer_ctl *xfer_ctl =
 709			container_of(xfer_hdr0, struct wa_xfer_ctl, hdr);
 710		xfer_ctl->bmAttribute = xfer->is_inbound ? 1 : 0;
 711		memcpy(&xfer_ctl->baSetupData, xfer->urb->setup_packet,
 712		       sizeof(xfer_ctl->baSetupData));
 713		break;
 714	}
 715	case WA_XFER_TYPE_BI:
 716		break;
 717	case WA_XFER_TYPE_ISO: {
 718		struct wa_xfer_hwaiso *xfer_iso =
 719			container_of(xfer_hdr0, struct wa_xfer_hwaiso, hdr);
 720		struct wa_xfer_packet_info_hwaiso *packet_desc =
 721			((void *)xfer_iso) + xfer_hdr_size;
 722
 723		/* populate the isoc section of the transfer request. */
 724		xfer_iso->dwNumOfPackets = cpu_to_le32(seg->isoc_frame_count);
 725		/* populate isoc packet descriptor. */
 726		__wa_setup_isoc_packet_descr(packet_desc, xfer, seg);
 727		break;
 728	}
 729	default:
 730		BUG();
 731	};
 732}
 733
 734/*
 735 * Callback for the OUT data phase of the segment request
 736 *
 737 * Check wa_seg_tr_cb(); most comments also apply here because this
 738 * function does almost the same thing and they work closely
 739 * together.
 740 *
 741 * If the seg request has failed but this DTO phase has succeeded,
 742 * wa_seg_tr_cb() has already failed the segment and moved the
 743 * status to WA_SEG_ERROR, so this will go through 'case 0' and
 744 * effectively do nothing.
 745 */
 746static void wa_seg_dto_cb(struct urb *urb)
 747{
 748	struct wa_seg *seg = urb->context;
 749	struct wa_xfer *xfer = seg->xfer;
 750	struct wahc *wa;
 751	struct device *dev;
 752	struct wa_rpipe *rpipe;
 753	unsigned long flags;
 754	unsigned rpipe_ready = 0;
 755	int data_send_done = 1, release_dto = 0, holding_dto = 0;
 756	u8 done = 0;
 757	int result;
 758
 759	/* free the sg if it was used. */
 760	kfree(urb->sg);
 761	urb->sg = NULL;
 762
 763	spin_lock_irqsave(&xfer->lock, flags);
 764	wa = xfer->wa;
 765	dev = &wa->usb_iface->dev;
 766	if (usb_pipeisoc(xfer->urb->pipe)) {
 767		/* Alereon HWA sends all isoc frames in a single transfer. */
 768		if (wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC)
 769			seg->isoc_frame_index += seg->isoc_frame_count;
 770		else
 771			seg->isoc_frame_index += 1;
 772		if (seg->isoc_frame_index < seg->isoc_frame_count) {
 773			data_send_done = 0;
 774			holding_dto = 1; /* checked in error cases. */
 775			/*
 776			 * if this is the last isoc frame of the segment, we
 777			 * can release DTO after sending this frame.
 778			 */
 779			if ((seg->isoc_frame_index + 1) >=
 780				seg->isoc_frame_count)
 781				release_dto = 1;
 782		}
 783		dev_dbg(dev, "xfer 0x%08X#%u: isoc frame = %d, holding_dto = %d, release_dto = %d.\n",
 784			wa_xfer_id(xfer), seg->index, seg->isoc_frame_index,
 785			holding_dto, release_dto);
 786	}
 787	spin_unlock_irqrestore(&xfer->lock, flags);
 788
 789	switch (urb->status) {
 790	case 0:
 791		spin_lock_irqsave(&xfer->lock, flags);
 792		seg->result += urb->actual_length;
 793		if (data_send_done) {
 794			dev_dbg(dev, "xfer 0x%08X#%u: data out done (%zu bytes)\n",
 795				wa_xfer_id(xfer), seg->index, seg->result);
 796			if (seg->status < WA_SEG_PENDING)
 797				seg->status = WA_SEG_PENDING;
 798		} else {
 799			/* should only hit this for isoc xfers. */
 800			/*
 801			 * Populate the dto URB with the next isoc frame buffer,
 802			 * send the URB and release DTO if we no longer need it.
 803			 */
 804			 __wa_populate_dto_urb_isoc(xfer, seg,
 805				seg->isoc_frame_offset + seg->isoc_frame_index);
 806
 807			/* resubmit the URB with the next isoc frame. */
 808			/* take a ref on resubmit. */
 809			wa_xfer_get(xfer);
 810			result = usb_submit_urb(seg->dto_urb, GFP_ATOMIC);
 811			if (result < 0) {
 812				dev_err(dev, "xfer 0x%08X#%u: DTO submit failed: %d\n",
 813				       wa_xfer_id(xfer), seg->index, result);
 814				spin_unlock_irqrestore(&xfer->lock, flags);
 815				goto error_dto_submit;
 816			}
 817		}
 818		spin_unlock_irqrestore(&xfer->lock, flags);
 819		if (release_dto) {
 820			__wa_dto_put(wa);
 821			wa_check_for_delayed_rpipes(wa);
 822		}
 823		break;
 824	case -ECONNRESET:	/* URB unlinked; no need to do anything */
 825	case -ENOENT:		/* as it was done by the who unlinked us */
 826		if (holding_dto) {
 827			__wa_dto_put(wa);
 828			wa_check_for_delayed_rpipes(wa);
 829		}
 830		break;
 831	default:		/* Other errors ... */
 832		dev_err(dev, "xfer 0x%08X#%u: data out error %d\n",
 833			wa_xfer_id(xfer), seg->index, urb->status);
 834		goto error_default;
 835	}
 836
 837	/* taken when this URB was submitted. */
 838	wa_xfer_put(xfer);
 839	return;
 840
 841error_dto_submit:
 842	/* taken on resubmit attempt. */
 843	wa_xfer_put(xfer);
 844error_default:
 845	spin_lock_irqsave(&xfer->lock, flags);
 846	rpipe = xfer->ep->hcpriv;
 847	if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
 848		    EDC_ERROR_TIMEFRAME)){
 849		dev_err(dev, "DTO: URB max acceptable errors exceeded, resetting device\n");
 850		wa_reset_all(wa);
 851	}
 852	if (seg->status != WA_SEG_ERROR) {
 853		seg->result = urb->status;
 854		__wa_xfer_abort(xfer);
 855		rpipe_ready = rpipe_avail_inc(rpipe);
 856		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_ERROR);
 857	}
 858	spin_unlock_irqrestore(&xfer->lock, flags);
 859	if (holding_dto) {
 860		__wa_dto_put(wa);
 861		wa_check_for_delayed_rpipes(wa);
 862	}
 863	if (done)
 864		wa_xfer_completion(xfer);
 865	if (rpipe_ready)
 866		wa_xfer_delayed_run(rpipe);
 867	/* taken when this URB was submitted. */
 868	wa_xfer_put(xfer);
 869}
 870
 871/*
 872 * Callback for the isoc packet descriptor phase of the segment request
 873 *
 874 * Check wa_seg_tr_cb(); most comments also apply here because this
 875 * function does almost the same thing and they work closely
 876 * together.
 877 *
 878 * If the seg request has failed but this phase has succeeded,
 879 * wa_seg_tr_cb() has already failed the segment and moved the
 880 * status to WA_SEG_ERROR, so this will go through 'case 0' and
 881 * effectively do nothing.
 882 */
 883static void wa_seg_iso_pack_desc_cb(struct urb *urb)
 884{
 885	struct wa_seg *seg = urb->context;
 886	struct wa_xfer *xfer = seg->xfer;
 887	struct wahc *wa;
 888	struct device *dev;
 889	struct wa_rpipe *rpipe;
 890	unsigned long flags;
 891	unsigned rpipe_ready = 0;
 892	u8 done = 0;
 893
 894	switch (urb->status) {
 895	case 0:
 896		spin_lock_irqsave(&xfer->lock, flags);
 897		wa = xfer->wa;
 898		dev = &wa->usb_iface->dev;
 899		dev_dbg(dev, "iso xfer %08X#%u: packet descriptor done\n",
 900			wa_xfer_id(xfer), seg->index);
 901		if (xfer->is_inbound && seg->status < WA_SEG_PENDING)
 902			seg->status = WA_SEG_PENDING;
 903		spin_unlock_irqrestore(&xfer->lock, flags);
 904		break;
 905	case -ECONNRESET:	/* URB unlinked; no need to do anything */
 906	case -ENOENT:		/* as it was done by the who unlinked us */
 907		break;
 908	default:		/* Other errors ... */
 909		spin_lock_irqsave(&xfer->lock, flags);
 910		wa = xfer->wa;
 911		dev = &wa->usb_iface->dev;
 912		rpipe = xfer->ep->hcpriv;
 913		pr_err_ratelimited("iso xfer %08X#%u: packet descriptor error %d\n",
 914				wa_xfer_id(xfer), seg->index, urb->status);
 915		if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
 916			    EDC_ERROR_TIMEFRAME)){
 917			dev_err(dev, "iso xfer: URB max acceptable errors exceeded, resetting device\n");
 918			wa_reset_all(wa);
 919		}
 920		if (seg->status != WA_SEG_ERROR) {
 921			usb_unlink_urb(seg->dto_urb);
 922			seg->result = urb->status;
 923			__wa_xfer_abort(xfer);
 924			rpipe_ready = rpipe_avail_inc(rpipe);
 925			done = __wa_xfer_mark_seg_as_done(xfer, seg,
 926					WA_SEG_ERROR);
 927		}
 928		spin_unlock_irqrestore(&xfer->lock, flags);
 929		if (done)
 930			wa_xfer_completion(xfer);
 931		if (rpipe_ready)
 932			wa_xfer_delayed_run(rpipe);
 933	}
 934	/* taken when this URB was submitted. */
 935	wa_xfer_put(xfer);
 936}
 937
 938/*
 939 * Callback for the segment request
 940 *
 941 * If successful transition state (unless already transitioned or
 942 * outbound transfer); otherwise, take a note of the error, mark this
 943 * segment done and try completion.
 944 *
 945 * Note we don't access until we are sure that the transfer hasn't
 946 * been cancelled (ECONNRESET, ENOENT), which could mean that
 947 * seg->xfer could be already gone.
 948 *
 949 * We have to check before setting the status to WA_SEG_PENDING
 950 * because sometimes the xfer result callback arrives before this
 951 * callback (geeeeeeze), so it might happen that we are already in
 952 * another state. As well, we don't set it if the transfer is not inbound,
 953 * as in that case, wa_seg_dto_cb will do it when the OUT data phase
 954 * finishes.
 955 */
 956static void wa_seg_tr_cb(struct urb *urb)
 957{
 958	struct wa_seg *seg = urb->context;
 959	struct wa_xfer *xfer = seg->xfer;
 960	struct wahc *wa;
 961	struct device *dev;
 962	struct wa_rpipe *rpipe;
 963	unsigned long flags;
 964	unsigned rpipe_ready;
 965	u8 done = 0;
 966
 967	switch (urb->status) {
 968	case 0:
 969		spin_lock_irqsave(&xfer->lock, flags);
 970		wa = xfer->wa;
 971		dev = &wa->usb_iface->dev;
 972		dev_dbg(dev, "xfer %p ID 0x%08X#%u: request done\n",
 973			xfer, wa_xfer_id(xfer), seg->index);
 974		if (xfer->is_inbound &&
 975			seg->status < WA_SEG_PENDING &&
 976			!(usb_pipeisoc(xfer->urb->pipe)))
 977			seg->status = WA_SEG_PENDING;
 978		spin_unlock_irqrestore(&xfer->lock, flags);
 979		break;
 980	case -ECONNRESET:	/* URB unlinked; no need to do anything */
 981	case -ENOENT:		/* as it was done by the who unlinked us */
 982		break;
 983	default:		/* Other errors ... */
 984		spin_lock_irqsave(&xfer->lock, flags);
 985		wa = xfer->wa;
 986		dev = &wa->usb_iface->dev;
 987		rpipe = xfer->ep->hcpriv;
 988		if (printk_ratelimit())
 989			dev_err(dev, "xfer %p ID 0x%08X#%u: request error %d\n",
 990				xfer, wa_xfer_id(xfer), seg->index,
 991				urb->status);
 992		if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
 993			    EDC_ERROR_TIMEFRAME)){
 994			dev_err(dev, "DTO: URB max acceptable errors "
 995				"exceeded, resetting device\n");
 996			wa_reset_all(wa);
 997		}
 998		usb_unlink_urb(seg->isoc_pack_desc_urb);
 999		usb_unlink_urb(seg->dto_urb);
1000		seg->result = urb->status;
1001		__wa_xfer_abort(xfer);
1002		rpipe_ready = rpipe_avail_inc(rpipe);
1003		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_ERROR);
1004		spin_unlock_irqrestore(&xfer->lock, flags);
1005		if (done)
1006			wa_xfer_completion(xfer);
1007		if (rpipe_ready)
1008			wa_xfer_delayed_run(rpipe);
1009	}
1010	/* taken when this URB was submitted. */
1011	wa_xfer_put(xfer);
1012}
1013
1014/*
1015 * Allocate an SG list to store bytes_to_transfer bytes and copy the
1016 * subset of the in_sg that matches the buffer subset
1017 * we are about to transfer.
1018 */
1019static struct scatterlist *wa_xfer_create_subset_sg(struct scatterlist *in_sg,
1020	const unsigned int bytes_transferred,
1021	const unsigned int bytes_to_transfer, int *out_num_sgs)
1022{
1023	struct scatterlist *out_sg;
1024	unsigned int bytes_processed = 0, offset_into_current_page_data = 0,
1025		nents;
1026	struct scatterlist *current_xfer_sg = in_sg;
1027	struct scatterlist *current_seg_sg, *last_seg_sg;
1028
1029	/* skip previously transferred pages. */
1030	while ((current_xfer_sg) &&
1031			(bytes_processed < bytes_transferred)) {
1032		bytes_processed += current_xfer_sg->length;
1033
1034		/* advance the sg if current segment starts on or past the
1035			next page. */
1036		if (bytes_processed <= bytes_transferred)
1037			current_xfer_sg = sg_next(current_xfer_sg);
1038	}
1039
1040	/* the data for the current segment starts in current_xfer_sg.
1041		calculate the offset. */
1042	if (bytes_processed > bytes_transferred) {
1043		offset_into_current_page_data = current_xfer_sg->length -
1044			(bytes_processed - bytes_transferred);
1045	}
1046
1047	/* calculate the number of pages needed by this segment. */
1048	nents = DIV_ROUND_UP((bytes_to_transfer +
1049		offset_into_current_page_data +
1050		current_xfer_sg->offset),
1051		PAGE_SIZE);
1052
1053	out_sg = kmalloc((sizeof(struct scatterlist) * nents), GFP_ATOMIC);
1054	if (out_sg) {
1055		sg_init_table(out_sg, nents);
1056
1057		/* copy the portion of the incoming SG that correlates to the
1058		 * data to be transferred by this segment to the segment SG. */
1059		last_seg_sg = current_seg_sg = out_sg;
1060		bytes_processed = 0;
1061
1062		/* reset nents and calculate the actual number of sg entries
1063			needed. */
1064		nents = 0;
1065		while ((bytes_processed < bytes_to_transfer) &&
1066				current_seg_sg && current_xfer_sg) {
1067			unsigned int page_len = min((current_xfer_sg->length -
1068				offset_into_current_page_data),
1069				(bytes_to_transfer - bytes_processed));
1070
1071			sg_set_page(current_seg_sg, sg_page(current_xfer_sg),
1072				page_len,
1073				current_xfer_sg->offset +
1074				offset_into_current_page_data);
1075
1076			bytes_processed += page_len;
1077
1078			last_seg_sg = current_seg_sg;
1079			current_seg_sg = sg_next(current_seg_sg);
1080			current_xfer_sg = sg_next(current_xfer_sg);
1081
1082			/* only the first page may require additional offset. */
1083			offset_into_current_page_data = 0;
1084			nents++;
1085		}
1086
1087		/* update num_sgs and terminate the list since we may have
1088		 *  concatenated pages. */
1089		sg_mark_end(last_seg_sg);
1090		*out_num_sgs = nents;
1091	}
1092
1093	return out_sg;
1094}
1095
1096/*
1097 * Populate DMA buffer info for the isoc dto urb.
1098 */
1099static void __wa_populate_dto_urb_isoc(struct wa_xfer *xfer,
1100	struct wa_seg *seg, int curr_iso_frame)
1101{
1102	seg->dto_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1103	seg->dto_urb->sg = NULL;
1104	seg->dto_urb->num_sgs = 0;
1105	/* dto urb buffer address pulled from iso_frame_desc. */
1106	seg->dto_urb->transfer_dma = xfer->urb->transfer_dma +
1107		xfer->urb->iso_frame_desc[curr_iso_frame].offset;
1108	/* The Alereon HWA sends a single URB with all isoc segs. */
1109	if (xfer->wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC)
1110		seg->dto_urb->transfer_buffer_length = seg->isoc_size;
1111	else
1112		seg->dto_urb->transfer_buffer_length =
1113			xfer->urb->iso_frame_desc[curr_iso_frame].length;
1114}
1115
1116/*
1117 * Populate buffer ptr and size, DMA buffer or SG list for the dto urb.
1118 */
1119static int __wa_populate_dto_urb(struct wa_xfer *xfer,
1120	struct wa_seg *seg, size_t buf_itr_offset, size_t buf_itr_size)
1121{
1122	int result = 0;
1123
1124	if (xfer->is_dma) {
1125		seg->dto_urb->transfer_dma =
1126			xfer->urb->transfer_dma + buf_itr_offset;
1127		seg->dto_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1128		seg->dto_urb->sg = NULL;
1129		seg->dto_urb->num_sgs = 0;
1130	} else {
1131		/* do buffer or SG processing. */
1132		seg->dto_urb->transfer_flags &=
1133			~URB_NO_TRANSFER_DMA_MAP;
1134		/* this should always be 0 before a resubmit. */
1135		seg->dto_urb->num_mapped_sgs = 0;
1136
1137		if (xfer->urb->transfer_buffer) {
1138			seg->dto_urb->transfer_buffer =
1139				xfer->urb->transfer_buffer +
1140				buf_itr_offset;
1141			seg->dto_urb->sg = NULL;
1142			seg->dto_urb->num_sgs = 0;
1143		} else {
1144			seg->dto_urb->transfer_buffer = NULL;
1145
1146			/*
1147			 * allocate an SG list to store seg_size bytes
1148			 * and copy the subset of the xfer->urb->sg that
1149			 * matches the buffer subset we are about to
1150			 * read.
1151			 */
1152			seg->dto_urb->sg = wa_xfer_create_subset_sg(
1153				xfer->urb->sg,
1154				buf_itr_offset, buf_itr_size,
1155				&(seg->dto_urb->num_sgs));
1156			if (!(seg->dto_urb->sg))
1157				result = -ENOMEM;
1158		}
1159	}
1160	seg->dto_urb->transfer_buffer_length = buf_itr_size;
1161
1162	return result;
1163}
1164
1165/*
1166 * Allocate the segs array and initialize each of them
1167 *
1168 * The segments are freed by wa_xfer_destroy() when the xfer use count
1169 * drops to zero; however, because each segment is given the same life
1170 * cycle as the USB URB it contains, it is actually freed by
1171 * usb_put_urb() on the contained USB URB (twisted, eh?).
1172 */
1173static int __wa_xfer_setup_segs(struct wa_xfer *xfer, size_t xfer_hdr_size)
1174{
1175	int result, cnt, isoc_frame_offset = 0;
1176	size_t alloc_size = sizeof(*xfer->seg[0])
1177		- sizeof(xfer->seg[0]->xfer_hdr) + xfer_hdr_size;
1178	struct usb_device *usb_dev = xfer->wa->usb_dev;
1179	const struct usb_endpoint_descriptor *dto_epd = xfer->wa->dto_epd;
1180	struct wa_seg *seg;
1181	size_t buf_itr, buf_size, buf_itr_size;
1182
1183	result = -ENOMEM;
1184	xfer->seg = kcalloc(xfer->segs, sizeof(xfer->seg[0]), GFP_ATOMIC);
1185	if (xfer->seg == NULL)
1186		goto error_segs_kzalloc;
1187	buf_itr = 0;
1188	buf_size = xfer->urb->transfer_buffer_length;
1189	for (cnt = 0; cnt < xfer->segs; cnt++) {
1190		size_t iso_pkt_descr_size = 0;
1191		int seg_isoc_frame_count = 0, seg_isoc_size = 0;
1192
1193		/*
1194		 * Adjust the size of the segment object to contain space for
1195		 * the isoc packet descriptor buffer.
1196		 */
1197		if (usb_pipeisoc(xfer->urb->pipe)) {
1198			seg_isoc_frame_count =
1199				__wa_seg_calculate_isoc_frame_count(xfer,
1200					isoc_frame_offset, &seg_isoc_size);
1201
1202			iso_pkt_descr_size =
1203				sizeof(struct wa_xfer_packet_info_hwaiso) +
1204				(seg_isoc_frame_count * sizeof(__le16));
1205		}
 
1206		seg = xfer->seg[cnt] = kmalloc(alloc_size + iso_pkt_descr_size,
1207						GFP_ATOMIC);
1208		if (seg == NULL)
1209			goto error_seg_kmalloc;
1210		wa_seg_init(seg);
1211		seg->xfer = xfer;
1212		seg->index = cnt;
1213		usb_fill_bulk_urb(&seg->tr_urb, usb_dev,
1214				  usb_sndbulkpipe(usb_dev,
1215						  dto_epd->bEndpointAddress),
1216				  &seg->xfer_hdr, xfer_hdr_size,
1217				  wa_seg_tr_cb, seg);
1218		buf_itr_size = min(buf_size, xfer->seg_size);
1219
1220		if (usb_pipeisoc(xfer->urb->pipe)) {
1221			seg->isoc_frame_count = seg_isoc_frame_count;
1222			seg->isoc_frame_offset = isoc_frame_offset;
1223			seg->isoc_size = seg_isoc_size;
1224			/* iso packet descriptor. */
1225			seg->isoc_pack_desc_urb =
1226					usb_alloc_urb(0, GFP_ATOMIC);
1227			if (seg->isoc_pack_desc_urb == NULL)
1228				goto error_iso_pack_desc_alloc;
1229			/*
1230			 * The buffer for the isoc packet descriptor starts
1231			 * after the transfer request header in the
1232			 * segment object memory buffer.
1233			 */
1234			usb_fill_bulk_urb(
1235				seg->isoc_pack_desc_urb, usb_dev,
1236				usb_sndbulkpipe(usb_dev,
1237					dto_epd->bEndpointAddress),
1238				(void *)(&seg->xfer_hdr) +
1239					xfer_hdr_size,
1240				iso_pkt_descr_size,
1241				wa_seg_iso_pack_desc_cb, seg);
1242
1243			/* adjust starting frame offset for next seg. */
1244			isoc_frame_offset += seg_isoc_frame_count;
1245		}
1246
1247		if (xfer->is_inbound == 0 && buf_size > 0) {
1248			/* outbound data. */
1249			seg->dto_urb = usb_alloc_urb(0, GFP_ATOMIC);
1250			if (seg->dto_urb == NULL)
1251				goto error_dto_alloc;
1252			usb_fill_bulk_urb(
1253				seg->dto_urb, usb_dev,
1254				usb_sndbulkpipe(usb_dev,
1255						dto_epd->bEndpointAddress),
1256				NULL, 0, wa_seg_dto_cb, seg);
1257
1258			if (usb_pipeisoc(xfer->urb->pipe)) {
1259				/*
1260				 * Fill in the xfer buffer information for the
1261				 * first isoc frame.  Subsequent frames in this
1262				 * segment will be filled in and sent from the
1263				 * DTO completion routine, if needed.
1264				 */
1265				__wa_populate_dto_urb_isoc(xfer, seg,
1266					seg->isoc_frame_offset);
1267			} else {
1268				/* fill in the xfer buffer information. */
1269				result = __wa_populate_dto_urb(xfer, seg,
1270							buf_itr, buf_itr_size);
1271				if (result < 0)
1272					goto error_seg_outbound_populate;
1273
1274				buf_itr += buf_itr_size;
1275				buf_size -= buf_itr_size;
1276			}
1277		}
1278		seg->status = WA_SEG_READY;
1279	}
1280	return 0;
1281
1282	/*
1283	 * Free the memory for the current segment which failed to init.
1284	 * Use the fact that cnt is left at were it failed.  The remaining
1285	 * segments will be cleaned up by wa_xfer_destroy.
1286	 */
1287error_seg_outbound_populate:
1288	usb_free_urb(xfer->seg[cnt]->dto_urb);
1289error_dto_alloc:
1290	usb_free_urb(xfer->seg[cnt]->isoc_pack_desc_urb);
1291error_iso_pack_desc_alloc:
1292	kfree(xfer->seg[cnt]);
1293	xfer->seg[cnt] = NULL;
1294error_seg_kmalloc:
1295error_segs_kzalloc:
1296	return result;
1297}
1298
1299/*
1300 * Allocates all the stuff needed to submit a transfer
1301 *
1302 * Breaks the whole data buffer in a list of segments, each one has a
1303 * structure allocated to it and linked in xfer->seg[index]
1304 *
1305 * FIXME: merge setup_segs() and the last part of this function, no
1306 *        need to do two for loops when we could run everything in a
1307 *        single one
1308 */
1309static int __wa_xfer_setup(struct wa_xfer *xfer, struct urb *urb)
1310{
1311	int result;
1312	struct device *dev = &xfer->wa->usb_iface->dev;
1313	enum wa_xfer_type xfer_type = 0; /* shut up GCC */
1314	size_t xfer_hdr_size, cnt, transfer_size;
1315	struct wa_xfer_hdr *xfer_hdr0, *xfer_hdr;
1316
1317	result = __wa_xfer_setup_sizes(xfer, &xfer_type);
1318	if (result < 0)
1319		goto error_setup_sizes;
1320	xfer_hdr_size = result;
1321	result = __wa_xfer_setup_segs(xfer, xfer_hdr_size);
1322	if (result < 0) {
1323		dev_err(dev, "xfer %p: Failed to allocate %d segments: %d\n",
1324			xfer, xfer->segs, result);
1325		goto error_setup_segs;
1326	}
1327	/* Fill the first header */
1328	xfer_hdr0 = &xfer->seg[0]->xfer_hdr;
1329	wa_xfer_id_init(xfer);
1330	__wa_xfer_setup_hdr0(xfer, xfer_hdr0, xfer_type, xfer_hdr_size);
1331
1332	/* Fill remaining headers */
1333	xfer_hdr = xfer_hdr0;
1334	if (xfer_type == WA_XFER_TYPE_ISO) {
1335		xfer_hdr0->dwTransferLength =
1336			cpu_to_le32(xfer->seg[0]->isoc_size);
1337		for (cnt = 1; cnt < xfer->segs; cnt++) {
1338			struct wa_xfer_packet_info_hwaiso *packet_desc;
1339			struct wa_seg *seg = xfer->seg[cnt];
1340			struct wa_xfer_hwaiso *xfer_iso;
1341
1342			xfer_hdr = &seg->xfer_hdr;
1343			xfer_iso = container_of(xfer_hdr,
1344						struct wa_xfer_hwaiso, hdr);
1345			packet_desc = ((void *)xfer_hdr) + xfer_hdr_size;
1346			/*
1347			 * Copy values from the 0th header. Segment specific
1348			 * values are set below.
1349			 */
1350			memcpy(xfer_hdr, xfer_hdr0, xfer_hdr_size);
1351			xfer_hdr->bTransferSegment = cnt;
1352			xfer_hdr->dwTransferLength =
1353				cpu_to_le32(seg->isoc_size);
1354			xfer_iso->dwNumOfPackets =
1355					cpu_to_le32(seg->isoc_frame_count);
1356			__wa_setup_isoc_packet_descr(packet_desc, xfer, seg);
1357			seg->status = WA_SEG_READY;
1358		}
1359	} else {
1360		transfer_size = urb->transfer_buffer_length;
1361		xfer_hdr0->dwTransferLength = transfer_size > xfer->seg_size ?
1362			cpu_to_le32(xfer->seg_size) :
1363			cpu_to_le32(transfer_size);
1364		transfer_size -=  xfer->seg_size;
1365		for (cnt = 1; cnt < xfer->segs; cnt++) {
1366			xfer_hdr = &xfer->seg[cnt]->xfer_hdr;
1367			memcpy(xfer_hdr, xfer_hdr0, xfer_hdr_size);
1368			xfer_hdr->bTransferSegment = cnt;
1369			xfer_hdr->dwTransferLength =
1370				transfer_size > xfer->seg_size ?
1371					cpu_to_le32(xfer->seg_size)
1372					: cpu_to_le32(transfer_size);
1373			xfer->seg[cnt]->status = WA_SEG_READY;
1374			transfer_size -=  xfer->seg_size;
1375		}
1376	}
1377	xfer_hdr->bTransferSegment |= 0x80;	/* this is the last segment */
1378	result = 0;
1379error_setup_segs:
1380error_setup_sizes:
1381	return result;
1382}
1383
1384/*
1385 *
1386 *
1387 * rpipe->seg_lock is held!
1388 */
1389static int __wa_seg_submit(struct wa_rpipe *rpipe, struct wa_xfer *xfer,
1390			   struct wa_seg *seg, int *dto_done)
1391{
1392	int result;
1393
1394	/* default to done unless we encounter a multi-frame isoc segment. */
1395	*dto_done = 1;
1396
1397	/*
1398	 * Take a ref for each segment urb so the xfer cannot disappear until
1399	 * all of the callbacks run.
1400	 */
1401	wa_xfer_get(xfer);
1402	/* submit the transfer request. */
1403	seg->status = WA_SEG_SUBMITTED;
1404	result = usb_submit_urb(&seg->tr_urb, GFP_ATOMIC);
1405	if (result < 0) {
1406		pr_err("%s: xfer %p#%u: REQ submit failed: %d\n",
1407		       __func__, xfer, seg->index, result);
1408		wa_xfer_put(xfer);
1409		goto error_tr_submit;
1410	}
1411	/* submit the isoc packet descriptor if present. */
1412	if (seg->isoc_pack_desc_urb) {
1413		wa_xfer_get(xfer);
1414		result = usb_submit_urb(seg->isoc_pack_desc_urb, GFP_ATOMIC);
1415		seg->isoc_frame_index = 0;
1416		if (result < 0) {
1417			pr_err("%s: xfer %p#%u: ISO packet descriptor submit failed: %d\n",
1418			       __func__, xfer, seg->index, result);
1419			wa_xfer_put(xfer);
1420			goto error_iso_pack_desc_submit;
1421		}
1422	}
1423	/* submit the out data if this is an out request. */
1424	if (seg->dto_urb) {
1425		struct wahc *wa = xfer->wa;
1426		wa_xfer_get(xfer);
1427		result = usb_submit_urb(seg->dto_urb, GFP_ATOMIC);
1428		if (result < 0) {
1429			pr_err("%s: xfer %p#%u: DTO submit failed: %d\n",
1430			       __func__, xfer, seg->index, result);
1431			wa_xfer_put(xfer);
1432			goto error_dto_submit;
1433		}
1434		/*
1435		 * If this segment contains more than one isoc frame, hold
1436		 * onto the dto resource until we send all frames.
1437		 * Only applies to non-Alereon devices.
1438		 */
1439		if (((wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC) == 0)
1440			&& (seg->isoc_frame_count > 1))
1441			*dto_done = 0;
1442	}
1443	rpipe_avail_dec(rpipe);
1444	return 0;
1445
1446error_dto_submit:
1447	usb_unlink_urb(seg->isoc_pack_desc_urb);
1448error_iso_pack_desc_submit:
1449	usb_unlink_urb(&seg->tr_urb);
1450error_tr_submit:
1451	seg->status = WA_SEG_ERROR;
1452	seg->result = result;
1453	*dto_done = 1;
1454	return result;
1455}
1456
1457/*
1458 * Execute more queued request segments until the maximum concurrent allowed.
1459 * Return true if the DTO resource was acquired and released.
1460 *
1461 * The ugly unlock/lock sequence on the error path is needed as the
1462 * xfer->lock normally nests the seg_lock and not viceversa.
1463 */
1464static int __wa_xfer_delayed_run(struct wa_rpipe *rpipe, int *dto_waiting)
1465{
1466	int result, dto_acquired = 0, dto_done = 0;
1467	struct device *dev = &rpipe->wa->usb_iface->dev;
1468	struct wa_seg *seg;
1469	struct wa_xfer *xfer;
1470	unsigned long flags;
1471
1472	*dto_waiting = 0;
1473
1474	spin_lock_irqsave(&rpipe->seg_lock, flags);
1475	while (atomic_read(&rpipe->segs_available) > 0
1476	      && !list_empty(&rpipe->seg_list)
1477	      && (dto_acquired = __wa_dto_try_get(rpipe->wa))) {
1478		seg = list_first_entry(&(rpipe->seg_list), struct wa_seg,
1479				 list_node);
1480		list_del(&seg->list_node);
1481		xfer = seg->xfer;
1482		/*
1483		 * Get a reference to the xfer in case the callbacks for the
1484		 * URBs submitted by __wa_seg_submit attempt to complete
1485		 * the xfer before this function completes.
1486		 */
1487		wa_xfer_get(xfer);
1488		result = __wa_seg_submit(rpipe, xfer, seg, &dto_done);
1489		/* release the dto resource if this RPIPE is done with it. */
1490		if (dto_done)
1491			__wa_dto_put(rpipe->wa);
1492		dev_dbg(dev, "xfer %p ID %08X#%u submitted from delayed [%d segments available] %d\n",
1493			xfer, wa_xfer_id(xfer), seg->index,
1494			atomic_read(&rpipe->segs_available), result);
1495		if (unlikely(result < 0)) {
1496			int done;
1497
1498			spin_unlock_irqrestore(&rpipe->seg_lock, flags);
1499			spin_lock_irqsave(&xfer->lock, flags);
1500			__wa_xfer_abort(xfer);
1501			/*
1502			 * This seg was marked as submitted when it was put on
1503			 * the RPIPE seg_list.  Mark it done.
1504			 */
1505			xfer->segs_done++;
1506			done = __wa_xfer_is_done(xfer);
1507			spin_unlock_irqrestore(&xfer->lock, flags);
1508			if (done)
1509				wa_xfer_completion(xfer);
1510			spin_lock_irqsave(&rpipe->seg_lock, flags);
1511		}
1512		wa_xfer_put(xfer);
1513	}
1514	/*
1515	 * Mark this RPIPE as waiting if dto was not acquired, there are
1516	 * delayed segs and no active transfers to wake us up later.
1517	 */
1518	if (!dto_acquired && !list_empty(&rpipe->seg_list)
1519		&& (atomic_read(&rpipe->segs_available) ==
1520			le16_to_cpu(rpipe->descr.wRequests)))
1521		*dto_waiting = 1;
1522
1523	spin_unlock_irqrestore(&rpipe->seg_lock, flags);
1524
1525	return dto_done;
1526}
1527
1528static void wa_xfer_delayed_run(struct wa_rpipe *rpipe)
1529{
1530	int dto_waiting;
1531	int dto_done = __wa_xfer_delayed_run(rpipe, &dto_waiting);
1532
1533	/*
1534	 * If this RPIPE is waiting on the DTO resource, add it to the tail of
1535	 * the waiting list.
1536	 * Otherwise, if the WA DTO resource was acquired and released by
1537	 *  __wa_xfer_delayed_run, another RPIPE may have attempted to acquire
1538	 * DTO and failed during that time.  Check the delayed list and process
1539	 * any waiters.  Start searching from the next RPIPE index.
1540	 */
1541	if (dto_waiting)
1542		wa_add_delayed_rpipe(rpipe->wa, rpipe);
1543	else if (dto_done)
1544		wa_check_for_delayed_rpipes(rpipe->wa);
1545}
1546
1547/*
1548 *
1549 * xfer->lock is taken
1550 *
1551 * On failure submitting we just stop submitting and return error;
1552 * wa_urb_enqueue_b() will execute the completion path
1553 */
1554static int __wa_xfer_submit(struct wa_xfer *xfer)
1555{
1556	int result, dto_acquired = 0, dto_done = 0, dto_waiting = 0;
1557	struct wahc *wa = xfer->wa;
1558	struct device *dev = &wa->usb_iface->dev;
1559	unsigned cnt;
1560	struct wa_seg *seg;
1561	unsigned long flags;
1562	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
1563	size_t maxrequests = le16_to_cpu(rpipe->descr.wRequests);
1564	u8 available;
1565	u8 empty;
1566
1567	spin_lock_irqsave(&wa->xfer_list_lock, flags);
1568	list_add_tail(&xfer->list_node, &wa->xfer_list);
1569	spin_unlock_irqrestore(&wa->xfer_list_lock, flags);
1570
1571	BUG_ON(atomic_read(&rpipe->segs_available) > maxrequests);
1572	result = 0;
1573	spin_lock_irqsave(&rpipe->seg_lock, flags);
1574	for (cnt = 0; cnt < xfer->segs; cnt++) {
1575		int delay_seg = 1;
1576
1577		available = atomic_read(&rpipe->segs_available);
1578		empty = list_empty(&rpipe->seg_list);
1579		seg = xfer->seg[cnt];
1580		if (available && empty) {
1581			/*
1582			 * Only attempt to acquire DTO if we have a segment
1583			 * to send.
1584			 */
1585			dto_acquired = __wa_dto_try_get(rpipe->wa);
1586			if (dto_acquired) {
1587				delay_seg = 0;
1588				result = __wa_seg_submit(rpipe, xfer, seg,
1589							&dto_done);
1590				dev_dbg(dev, "xfer %p ID 0x%08X#%u: available %u empty %u submitted\n",
1591					xfer, wa_xfer_id(xfer), cnt, available,
1592					empty);
1593				if (dto_done)
1594					__wa_dto_put(rpipe->wa);
1595
1596				if (result < 0) {
1597					__wa_xfer_abort(xfer);
1598					goto error_seg_submit;
1599				}
1600			}
1601		}
1602
1603		if (delay_seg) {
1604			dev_dbg(dev, "xfer %p ID 0x%08X#%u: available %u empty %u delayed\n",
1605				xfer, wa_xfer_id(xfer), cnt, available,  empty);
1606			seg->status = WA_SEG_DELAYED;
1607			list_add_tail(&seg->list_node, &rpipe->seg_list);
1608		}
1609		xfer->segs_submitted++;
1610	}
1611error_seg_submit:
1612	/*
1613	 * Mark this RPIPE as waiting if dto was not acquired, there are
1614	 * delayed segs and no active transfers to wake us up later.
1615	 */
1616	if (!dto_acquired && !list_empty(&rpipe->seg_list)
1617		&& (atomic_read(&rpipe->segs_available) ==
1618			le16_to_cpu(rpipe->descr.wRequests)))
1619		dto_waiting = 1;
1620	spin_unlock_irqrestore(&rpipe->seg_lock, flags);
1621
1622	if (dto_waiting)
1623		wa_add_delayed_rpipe(rpipe->wa, rpipe);
1624	else if (dto_done)
1625		wa_check_for_delayed_rpipes(rpipe->wa);
1626
1627	return result;
1628}
1629
1630/*
1631 * Second part of a URB/transfer enqueuement
1632 *
1633 * Assumes this comes from wa_urb_enqueue() [maybe through
1634 * wa_urb_enqueue_run()]. At this point:
1635 *
1636 * xfer->wa	filled and refcounted
1637 * xfer->ep	filled with rpipe refcounted if
1638 *              delayed == 0
1639 * xfer->urb 	filled and refcounted (this is the case when called
1640 *              from wa_urb_enqueue() as we come from usb_submit_urb()
1641 *              and when called by wa_urb_enqueue_run(), as we took an
1642 *              extra ref dropped by _run() after we return).
1643 * xfer->gfp	filled
1644 *
1645 * If we fail at __wa_xfer_submit(), then we just check if we are done
1646 * and if so, we run the completion procedure. However, if we are not
1647 * yet done, we do nothing and wait for the completion handlers from
1648 * the submitted URBs or from the xfer-result path to kick in. If xfer
1649 * result never kicks in, the xfer will timeout from the USB code and
1650 * dequeue() will be called.
1651 */
1652static int wa_urb_enqueue_b(struct wa_xfer *xfer)
1653{
1654	int result;
1655	unsigned long flags;
1656	struct urb *urb = xfer->urb;
1657	struct wahc *wa = xfer->wa;
1658	struct wusbhc *wusbhc = wa->wusb;
1659	struct wusb_dev *wusb_dev;
1660	unsigned done;
1661
1662	result = rpipe_get_by_ep(wa, xfer->ep, urb, xfer->gfp);
1663	if (result < 0) {
1664		pr_err("%s: error_rpipe_get\n", __func__);
1665		goto error_rpipe_get;
1666	}
1667	result = -ENODEV;
1668	/* FIXME: segmentation broken -- kills DWA */
1669	mutex_lock(&wusbhc->mutex);		/* get a WUSB dev */
1670	if (urb->dev == NULL) {
1671		mutex_unlock(&wusbhc->mutex);
1672		pr_err("%s: error usb dev gone\n", __func__);
1673		goto error_dev_gone;
1674	}
1675	wusb_dev = __wusb_dev_get_by_usb_dev(wusbhc, urb->dev);
1676	if (wusb_dev == NULL) {
1677		mutex_unlock(&wusbhc->mutex);
1678		dev_err(&(urb->dev->dev), "%s: error wusb dev gone\n",
1679			__func__);
1680		goto error_dev_gone;
1681	}
1682	mutex_unlock(&wusbhc->mutex);
1683
1684	spin_lock_irqsave(&xfer->lock, flags);
1685	xfer->wusb_dev = wusb_dev;
1686	result = urb->status;
1687	if (urb->status != -EINPROGRESS) {
1688		dev_err(&(urb->dev->dev), "%s: error_dequeued\n", __func__);
1689		goto error_dequeued;
1690	}
1691
1692	result = __wa_xfer_setup(xfer, urb);
1693	if (result < 0) {
1694		dev_err(&(urb->dev->dev), "%s: error_xfer_setup\n", __func__);
1695		goto error_xfer_setup;
1696	}
1697	/*
1698	 * Get a xfer reference since __wa_xfer_submit starts asynchronous
1699	 * operations that may try to complete the xfer before this function
1700	 * exits.
1701	 */
1702	wa_xfer_get(xfer);
1703	result = __wa_xfer_submit(xfer);
1704	if (result < 0) {
1705		dev_err(&(urb->dev->dev), "%s: error_xfer_submit\n", __func__);
1706		goto error_xfer_submit;
1707	}
1708	spin_unlock_irqrestore(&xfer->lock, flags);
1709	wa_xfer_put(xfer);
1710	return 0;
1711
1712	/*
1713	 * this is basically wa_xfer_completion() broken up wa_xfer_giveback()
1714	 * does a wa_xfer_put() that will call wa_xfer_destroy() and undo
1715	 * setup().
1716	 */
1717error_xfer_setup:
1718error_dequeued:
1719	spin_unlock_irqrestore(&xfer->lock, flags);
1720	/* FIXME: segmentation broken, kills DWA */
1721	if (wusb_dev)
1722		wusb_dev_put(wusb_dev);
1723error_dev_gone:
1724	rpipe_put(xfer->ep->hcpriv);
1725error_rpipe_get:
1726	xfer->result = result;
1727	return result;
1728
1729error_xfer_submit:
1730	done = __wa_xfer_is_done(xfer);
1731	xfer->result = result;
1732	spin_unlock_irqrestore(&xfer->lock, flags);
1733	if (done)
1734		wa_xfer_completion(xfer);
1735	wa_xfer_put(xfer);
1736	/* return success since the completion routine will run. */
1737	return 0;
1738}
1739
1740/*
1741 * Execute the delayed transfers in the Wire Adapter @wa
1742 *
1743 * We need to be careful here, as dequeue() could be called in the
1744 * middle.  That's why we do the whole thing under the
1745 * wa->xfer_list_lock. If dequeue() jumps in, it first locks xfer->lock
1746 * and then checks the list -- so as we would be acquiring in inverse
1747 * order, we move the delayed list to a separate list while locked and then
1748 * submit them without the list lock held.
1749 */
1750void wa_urb_enqueue_run(struct work_struct *ws)
1751{
1752	struct wahc *wa = container_of(ws, struct wahc, xfer_enqueue_work);
1753	struct wa_xfer *xfer, *next;
1754	struct urb *urb;
1755	LIST_HEAD(tmp_list);
1756
1757	/* Create a copy of the wa->xfer_delayed_list while holding the lock */
1758	spin_lock_irq(&wa->xfer_list_lock);
1759	list_cut_position(&tmp_list, &wa->xfer_delayed_list,
1760			wa->xfer_delayed_list.prev);
1761	spin_unlock_irq(&wa->xfer_list_lock);
1762
1763	/*
1764	 * enqueue from temp list without list lock held since wa_urb_enqueue_b
1765	 * can take xfer->lock as well as lock mutexes.
1766	 */
1767	list_for_each_entry_safe(xfer, next, &tmp_list, list_node) {
1768		list_del_init(&xfer->list_node);
1769
1770		urb = xfer->urb;
1771		if (wa_urb_enqueue_b(xfer) < 0)
1772			wa_xfer_giveback(xfer);
1773		usb_put_urb(urb);	/* taken when queuing */
1774	}
1775}
1776EXPORT_SYMBOL_GPL(wa_urb_enqueue_run);
1777
1778/*
1779 * Process the errored transfers on the Wire Adapter outside of interrupt.
1780 */
1781void wa_process_errored_transfers_run(struct work_struct *ws)
1782{
1783	struct wahc *wa = container_of(ws, struct wahc, xfer_error_work);
1784	struct wa_xfer *xfer, *next;
1785	LIST_HEAD(tmp_list);
1786
1787	pr_info("%s: Run delayed STALL processing.\n", __func__);
1788
1789	/* Create a copy of the wa->xfer_errored_list while holding the lock */
1790	spin_lock_irq(&wa->xfer_list_lock);
1791	list_cut_position(&tmp_list, &wa->xfer_errored_list,
1792			wa->xfer_errored_list.prev);
1793	spin_unlock_irq(&wa->xfer_list_lock);
1794
1795	/*
1796	 * run rpipe_clear_feature_stalled from temp list without list lock
1797	 * held.
1798	 */
1799	list_for_each_entry_safe(xfer, next, &tmp_list, list_node) {
1800		struct usb_host_endpoint *ep;
1801		unsigned long flags;
1802		struct wa_rpipe *rpipe;
1803
1804		spin_lock_irqsave(&xfer->lock, flags);
1805		ep = xfer->ep;
1806		rpipe = ep->hcpriv;
1807		spin_unlock_irqrestore(&xfer->lock, flags);
1808
1809		/* clear RPIPE feature stalled without holding a lock. */
1810		rpipe_clear_feature_stalled(wa, ep);
1811
1812		/* complete the xfer. This removes it from the tmp list. */
1813		wa_xfer_completion(xfer);
1814
1815		/* check for work. */
1816		wa_xfer_delayed_run(rpipe);
1817	}
1818}
1819EXPORT_SYMBOL_GPL(wa_process_errored_transfers_run);
1820
1821/*
1822 * Submit a transfer to the Wire Adapter in a delayed way
1823 *
1824 * The process of enqueuing involves possible sleeps() [see
1825 * enqueue_b(), for the rpipe_get() and the mutex_lock()]. If we are
1826 * in an atomic section, we defer the enqueue_b() call--else we call direct.
1827 *
1828 * @urb: We own a reference to it done by the HCI Linux USB stack that
1829 *       will be given up by calling usb_hcd_giveback_urb() or by
1830 *       returning error from this function -> ergo we don't have to
1831 *       refcount it.
1832 */
1833int wa_urb_enqueue(struct wahc *wa, struct usb_host_endpoint *ep,
1834		   struct urb *urb, gfp_t gfp)
1835{
1836	int result;
1837	struct device *dev = &wa->usb_iface->dev;
1838	struct wa_xfer *xfer;
1839	unsigned long my_flags;
1840	unsigned cant_sleep = irqs_disabled() | in_atomic();
1841
1842	if ((urb->transfer_buffer == NULL)
1843	    && (urb->sg == NULL)
1844	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
1845	    && urb->transfer_buffer_length != 0) {
1846		dev_err(dev, "BUG? urb %p: NULL xfer buffer & NODMA\n", urb);
1847		dump_stack();
1848	}
1849
1850	spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1851	result = usb_hcd_link_urb_to_ep(&(wa->wusb->usb_hcd), urb);
1852	spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1853	if (result < 0)
1854		goto error_link_urb;
1855
1856	result = -ENOMEM;
1857	xfer = kzalloc(sizeof(*xfer), gfp);
1858	if (xfer == NULL)
1859		goto error_kmalloc;
1860
1861	result = -ENOENT;
1862	if (urb->status != -EINPROGRESS)	/* cancelled */
1863		goto error_dequeued;		/* before starting? */
1864	wa_xfer_init(xfer);
1865	xfer->wa = wa_get(wa);
1866	xfer->urb = urb;
1867	xfer->gfp = gfp;
1868	xfer->ep = ep;
1869	urb->hcpriv = xfer;
1870
1871	dev_dbg(dev, "xfer %p urb %p pipe 0x%02x [%d bytes] %s %s %s\n",
1872		xfer, urb, urb->pipe, urb->transfer_buffer_length,
1873		urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP ? "dma" : "nodma",
1874		urb->pipe & USB_DIR_IN ? "inbound" : "outbound",
1875		cant_sleep ? "deferred" : "inline");
1876
1877	if (cant_sleep) {
1878		usb_get_urb(urb);
1879		spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1880		list_add_tail(&xfer->list_node, &wa->xfer_delayed_list);
1881		spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1882		queue_work(wusbd, &wa->xfer_enqueue_work);
1883	} else {
1884		result = wa_urb_enqueue_b(xfer);
1885		if (result < 0) {
1886			/*
1887			 * URB submit/enqueue failed.  Clean up, return an
1888			 * error and do not run the callback.  This avoids
1889			 * an infinite submit/complete loop.
1890			 */
1891			dev_err(dev, "%s: URB enqueue failed: %d\n",
1892			   __func__, result);
1893			wa_put(xfer->wa);
1894			wa_xfer_put(xfer);
1895			spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1896			usb_hcd_unlink_urb_from_ep(&(wa->wusb->usb_hcd), urb);
1897			spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1898			return result;
1899		}
1900	}
1901	return 0;
1902
1903error_dequeued:
1904	kfree(xfer);
1905error_kmalloc:
1906	spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1907	usb_hcd_unlink_urb_from_ep(&(wa->wusb->usb_hcd), urb);
1908	spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1909error_link_urb:
1910	return result;
1911}
1912EXPORT_SYMBOL_GPL(wa_urb_enqueue);
1913
1914/*
1915 * Dequeue a URB and make sure uwb_hcd_giveback_urb() [completion
1916 * handler] is called.
1917 *
1918 * Until a transfer goes successfully through wa_urb_enqueue() it
1919 * needs to be dequeued with completion calling; when stuck in delayed
1920 * or before wa_xfer_setup() is called, we need to do completion.
1921 *
1922 *  not setup  If there is no hcpriv yet, that means that that enqueue
1923 *             still had no time to set the xfer up. Because
1924 *             urb->status should be other than -EINPROGRESS,
1925 *             enqueue() will catch that and bail out.
1926 *
1927 * If the transfer has gone through setup, we just need to clean it
1928 * up. If it has gone through submit(), we have to abort it [with an
1929 * asynch request] and then make sure we cancel each segment.
1930 *
1931 */
1932int wa_urb_dequeue(struct wahc *wa, struct urb *urb, int status)
1933{
1934	unsigned long flags, flags2;
1935	struct wa_xfer *xfer;
1936	struct wa_seg *seg;
1937	struct wa_rpipe *rpipe;
1938	unsigned cnt, done = 0, xfer_abort_pending;
1939	unsigned rpipe_ready = 0;
1940	int result;
1941
1942	/* check if it is safe to unlink. */
1943	spin_lock_irqsave(&wa->xfer_list_lock, flags);
1944	result = usb_hcd_check_unlink_urb(&(wa->wusb->usb_hcd), urb, status);
1945	if ((result == 0) && urb->hcpriv) {
1946		/*
1947		 * Get a xfer ref to prevent a race with wa_xfer_giveback
1948		 * cleaning up the xfer while we are working with it.
1949		 */
1950		wa_xfer_get(urb->hcpriv);
1951	}
1952	spin_unlock_irqrestore(&wa->xfer_list_lock, flags);
1953	if (result)
1954		return result;
1955
1956	xfer = urb->hcpriv;
1957	if (xfer == NULL)
1958		return -ENOENT;
1959	spin_lock_irqsave(&xfer->lock, flags);
1960	pr_debug("%s: DEQUEUE xfer id 0x%08X\n", __func__, wa_xfer_id(xfer));
1961	rpipe = xfer->ep->hcpriv;
1962	if (rpipe == NULL) {
1963		pr_debug("%s: xfer %p id 0x%08X has no RPIPE.  %s",
1964			__func__, xfer, wa_xfer_id(xfer),
1965			"Probably already aborted.\n" );
1966		result = -ENOENT;
1967		goto out_unlock;
1968	}
1969	/*
1970	 * Check for done to avoid racing with wa_xfer_giveback and completing
1971	 * twice.
1972	 */
1973	if (__wa_xfer_is_done(xfer)) {
1974		pr_debug("%s: xfer %p id 0x%08X already done.\n", __func__,
1975			xfer, wa_xfer_id(xfer));
1976		result = -ENOENT;
1977		goto out_unlock;
1978	}
1979	/* Check the delayed list -> if there, release and complete */
1980	spin_lock_irqsave(&wa->xfer_list_lock, flags2);
1981	if (!list_empty(&xfer->list_node) && xfer->seg == NULL)
1982		goto dequeue_delayed;
1983	spin_unlock_irqrestore(&wa->xfer_list_lock, flags2);
1984	if (xfer->seg == NULL)  	/* still hasn't reached */
1985		goto out_unlock;	/* setup(), enqueue_b() completes */
1986	/* Ok, the xfer is in flight already, it's been setup and submitted.*/
1987	xfer_abort_pending = __wa_xfer_abort(xfer) >= 0;
1988	/*
1989	 * grab the rpipe->seg_lock here to prevent racing with
1990	 * __wa_xfer_delayed_run.
1991	 */
1992	spin_lock(&rpipe->seg_lock);
1993	for (cnt = 0; cnt < xfer->segs; cnt++) {
1994		seg = xfer->seg[cnt];
1995		pr_debug("%s: xfer id 0x%08X#%d status = %d\n",
1996			__func__, wa_xfer_id(xfer), cnt, seg->status);
1997		switch (seg->status) {
1998		case WA_SEG_NOTREADY:
1999		case WA_SEG_READY:
2000			printk(KERN_ERR "xfer %p#%u: dequeue bad state %u\n",
2001			       xfer, cnt, seg->status);
2002			WARN_ON(1);
2003			break;
2004		case WA_SEG_DELAYED:
2005			/*
2006			 * delete from rpipe delayed list.  If no segments on
2007			 * this xfer have been submitted, __wa_xfer_is_done will
2008			 * trigger a giveback below.  Otherwise, the submitted
2009			 * segments will be completed in the DTI interrupt.
2010			 */
2011			seg->status = WA_SEG_ABORTED;
2012			seg->result = -ENOENT;
2013			list_del(&seg->list_node);
2014			xfer->segs_done++;
2015			break;
2016		case WA_SEG_DONE:
2017		case WA_SEG_ERROR:
2018		case WA_SEG_ABORTED:
2019			break;
2020			/*
2021			 * The buf_in data for a segment in the
2022			 * WA_SEG_DTI_PENDING state is actively being read.
2023			 * Let wa_buf_in_cb handle it since it will be called
2024			 * and will increment xfer->segs_done.  Cleaning up
2025			 * here could cause wa_buf_in_cb to access the xfer
2026			 * after it has been completed/freed.
2027			 */
2028		case WA_SEG_DTI_PENDING:
2029			break;
2030			/*
2031			 * In the states below, the HWA device already knows
2032			 * about the transfer.  If an abort request was sent,
2033			 * allow the HWA to process it and wait for the
2034			 * results.  Otherwise, the DTI state and seg completed
2035			 * counts can get out of sync.
2036			 */
2037		case WA_SEG_SUBMITTED:
2038		case WA_SEG_PENDING:
2039			/*
2040			 * Check if the abort was successfully sent.  This could
2041			 * be false if the HWA has been removed but we haven't
2042			 * gotten the disconnect notification yet.
2043			 */
2044			if (!xfer_abort_pending) {
2045				seg->status = WA_SEG_ABORTED;
2046				rpipe_ready = rpipe_avail_inc(rpipe);
2047				xfer->segs_done++;
2048			}
2049			break;
2050		}
2051	}
2052	spin_unlock(&rpipe->seg_lock);
2053	xfer->result = urb->status;	/* -ENOENT or -ECONNRESET */
2054	done = __wa_xfer_is_done(xfer);
2055	spin_unlock_irqrestore(&xfer->lock, flags);
2056	if (done)
2057		wa_xfer_completion(xfer);
2058	if (rpipe_ready)
2059		wa_xfer_delayed_run(rpipe);
2060	wa_xfer_put(xfer);
2061	return result;
2062
2063out_unlock:
2064	spin_unlock_irqrestore(&xfer->lock, flags);
2065	wa_xfer_put(xfer);
2066	return result;
2067
2068dequeue_delayed:
2069	list_del_init(&xfer->list_node);
2070	spin_unlock_irqrestore(&wa->xfer_list_lock, flags2);
2071	xfer->result = urb->status;
2072	spin_unlock_irqrestore(&xfer->lock, flags);
2073	wa_xfer_giveback(xfer);
2074	wa_xfer_put(xfer);
2075	usb_put_urb(urb);		/* we got a ref in enqueue() */
2076	return 0;
2077}
2078EXPORT_SYMBOL_GPL(wa_urb_dequeue);
2079
2080/*
2081 * Translation from WA status codes (WUSB1.0 Table 8.15) to errno
2082 * codes
2083 *
2084 * Positive errno values are internal inconsistencies and should be
2085 * flagged louder. Negative are to be passed up to the user in the
2086 * normal way.
2087 *
2088 * @status: USB WA status code -- high two bits are stripped.
2089 */
2090static int wa_xfer_status_to_errno(u8 status)
2091{
2092	int errno;
2093	u8 real_status = status;
2094	static int xlat[] = {
2095		[WA_XFER_STATUS_SUCCESS] = 		0,
2096		[WA_XFER_STATUS_HALTED] = 		-EPIPE,
2097		[WA_XFER_STATUS_DATA_BUFFER_ERROR] = 	-ENOBUFS,
2098		[WA_XFER_STATUS_BABBLE] = 		-EOVERFLOW,
2099		[WA_XFER_RESERVED] = 			EINVAL,
2100		[WA_XFER_STATUS_NOT_FOUND] =		0,
2101		[WA_XFER_STATUS_INSUFFICIENT_RESOURCE] = -ENOMEM,
2102		[WA_XFER_STATUS_TRANSACTION_ERROR] = 	-EILSEQ,
2103		[WA_XFER_STATUS_ABORTED] =		-ENOENT,
2104		[WA_XFER_STATUS_RPIPE_NOT_READY] = 	EINVAL,
2105		[WA_XFER_INVALID_FORMAT] = 		EINVAL,
2106		[WA_XFER_UNEXPECTED_SEGMENT_NUMBER] = 	EINVAL,
2107		[WA_XFER_STATUS_RPIPE_TYPE_MISMATCH] = 	EINVAL,
2108	};
2109	status &= 0x3f;
2110
2111	if (status == 0)
2112		return 0;
2113	if (status >= ARRAY_SIZE(xlat)) {
2114		printk_ratelimited(KERN_ERR "%s(): BUG? "
2115			       "Unknown WA transfer status 0x%02x\n",
2116			       __func__, real_status);
2117		return -EINVAL;
2118	}
2119	errno = xlat[status];
2120	if (unlikely(errno > 0)) {
2121		printk_ratelimited(KERN_ERR "%s(): BUG? "
2122			       "Inconsistent WA status: 0x%02x\n",
2123			       __func__, real_status);
2124		errno = -errno;
2125	}
2126	return errno;
2127}
2128
2129/*
2130 * If a last segment flag and/or a transfer result error is encountered,
2131 * no other segment transfer results will be returned from the device.
2132 * Mark the remaining submitted or pending xfers as completed so that
2133 * the xfer will complete cleanly.
2134 *
2135 * xfer->lock must be held
2136 *
2137 */
2138static void wa_complete_remaining_xfer_segs(struct wa_xfer *xfer,
2139		int starting_index, enum wa_seg_status status)
2140{
2141	int index;
2142	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
2143
2144	for (index = starting_index; index < xfer->segs_submitted; index++) {
2145		struct wa_seg *current_seg = xfer->seg[index];
2146
2147		BUG_ON(current_seg == NULL);
2148
2149		switch (current_seg->status) {
2150		case WA_SEG_SUBMITTED:
2151		case WA_SEG_PENDING:
2152		case WA_SEG_DTI_PENDING:
2153			rpipe_avail_inc(rpipe);
2154		/*
2155		 * do not increment RPIPE avail for the WA_SEG_DELAYED case
2156		 * since it has not been submitted to the RPIPE.
2157		 */
 
2158		case WA_SEG_DELAYED:
2159			xfer->segs_done++;
2160			current_seg->status = status;
2161			break;
2162		case WA_SEG_ABORTED:
2163			break;
2164		default:
2165			WARN(1, "%s: xfer 0x%08X#%d. bad seg status = %d\n",
2166				__func__, wa_xfer_id(xfer), index,
2167				current_seg->status);
2168			break;
2169		}
2170	}
2171}
2172
2173/* Populate the given urb based on the current isoc transfer state. */
2174static int __wa_populate_buf_in_urb_isoc(struct wahc *wa,
2175	struct urb *buf_in_urb, struct wa_xfer *xfer, struct wa_seg *seg)
2176{
2177	int urb_start_frame = seg->isoc_frame_index + seg->isoc_frame_offset;
2178	int seg_index, total_len = 0, urb_frame_index = urb_start_frame;
2179	struct usb_iso_packet_descriptor *iso_frame_desc =
2180						xfer->urb->iso_frame_desc;
2181	const int dti_packet_size = usb_endpoint_maxp(wa->dti_epd);
2182	int next_frame_contiguous;
2183	struct usb_iso_packet_descriptor *iso_frame;
2184
2185	BUG_ON(buf_in_urb->status == -EINPROGRESS);
2186
2187	/*
2188	 * If the current frame actual_length is contiguous with the next frame
2189	 * and actual_length is a multiple of the DTI endpoint max packet size,
2190	 * combine the current frame with the next frame in a single URB.  This
2191	 * reduces the number of URBs that must be submitted in that case.
2192	 */
2193	seg_index = seg->isoc_frame_index;
2194	do {
2195		next_frame_contiguous = 0;
2196
2197		iso_frame = &iso_frame_desc[urb_frame_index];
2198		total_len += iso_frame->actual_length;
2199		++urb_frame_index;
2200		++seg_index;
2201
2202		if (seg_index < seg->isoc_frame_count) {
2203			struct usb_iso_packet_descriptor *next_iso_frame;
2204
2205			next_iso_frame = &iso_frame_desc[urb_frame_index];
2206
2207			if ((iso_frame->offset + iso_frame->actual_length) ==
2208				next_iso_frame->offset)
2209				next_frame_contiguous = 1;
2210		}
2211	} while (next_frame_contiguous
2212			&& ((iso_frame->actual_length % dti_packet_size) == 0));
2213
2214	/* this should always be 0 before a resubmit. */
2215	buf_in_urb->num_mapped_sgs	= 0;
2216	buf_in_urb->transfer_dma = xfer->urb->transfer_dma +
2217		iso_frame_desc[urb_start_frame].offset;
2218	buf_in_urb->transfer_buffer_length = total_len;
2219	buf_in_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
2220	buf_in_urb->transfer_buffer = NULL;
2221	buf_in_urb->sg = NULL;
2222	buf_in_urb->num_sgs = 0;
2223	buf_in_urb->context = seg;
2224
2225	/* return the number of frames included in this URB. */
2226	return seg_index - seg->isoc_frame_index;
2227}
2228
2229/* Populate the given urb based on the current transfer state. */
2230static int wa_populate_buf_in_urb(struct urb *buf_in_urb, struct wa_xfer *xfer,
2231	unsigned int seg_idx, unsigned int bytes_transferred)
2232{
2233	int result = 0;
2234	struct wa_seg *seg = xfer->seg[seg_idx];
2235
2236	BUG_ON(buf_in_urb->status == -EINPROGRESS);
2237	/* this should always be 0 before a resubmit. */
2238	buf_in_urb->num_mapped_sgs	= 0;
2239
2240	if (xfer->is_dma) {
2241		buf_in_urb->transfer_dma = xfer->urb->transfer_dma
2242			+ (seg_idx * xfer->seg_size);
2243		buf_in_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
2244		buf_in_urb->transfer_buffer = NULL;
2245		buf_in_urb->sg = NULL;
2246		buf_in_urb->num_sgs = 0;
2247	} else {
2248		/* do buffer or SG processing. */
2249		buf_in_urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
2250
2251		if (xfer->urb->transfer_buffer) {
2252			buf_in_urb->transfer_buffer =
2253				xfer->urb->transfer_buffer
2254				+ (seg_idx * xfer->seg_size);
2255			buf_in_urb->sg = NULL;
2256			buf_in_urb->num_sgs = 0;
2257		} else {
2258			/* allocate an SG list to store seg_size bytes
2259				and copy the subset of the xfer->urb->sg
2260				that matches the buffer subset we are
2261				about to read. */
2262			buf_in_urb->sg = wa_xfer_create_subset_sg(
2263				xfer->urb->sg,
2264				seg_idx * xfer->seg_size,
2265				bytes_transferred,
2266				&(buf_in_urb->num_sgs));
2267
2268			if (!(buf_in_urb->sg)) {
2269				buf_in_urb->num_sgs	= 0;
2270				result = -ENOMEM;
2271			}
2272			buf_in_urb->transfer_buffer = NULL;
2273		}
2274	}
2275	buf_in_urb->transfer_buffer_length = bytes_transferred;
2276	buf_in_urb->context = seg;
2277
2278	return result;
2279}
2280
2281/*
2282 * Process a xfer result completion message
2283 *
2284 * inbound transfers: need to schedule a buf_in_urb read
2285 *
2286 * FIXME: this function needs to be broken up in parts
2287 */
2288static void wa_xfer_result_chew(struct wahc *wa, struct wa_xfer *xfer,
2289		struct wa_xfer_result *xfer_result)
2290{
2291	int result;
2292	struct device *dev = &wa->usb_iface->dev;
2293	unsigned long flags;
2294	unsigned int seg_idx;
2295	struct wa_seg *seg;
2296	struct wa_rpipe *rpipe;
2297	unsigned done = 0;
2298	u8 usb_status;
2299	unsigned rpipe_ready = 0;
2300	unsigned bytes_transferred = le32_to_cpu(xfer_result->dwTransferLength);
2301	struct urb *buf_in_urb = &(wa->buf_in_urbs[0]);
2302
2303	spin_lock_irqsave(&xfer->lock, flags);
2304	seg_idx = xfer_result->bTransferSegment & 0x7f;
2305	if (unlikely(seg_idx >= xfer->segs))
2306		goto error_bad_seg;
2307	seg = xfer->seg[seg_idx];
2308	rpipe = xfer->ep->hcpriv;
2309	usb_status = xfer_result->bTransferStatus;
2310	dev_dbg(dev, "xfer %p ID 0x%08X#%u: bTransferStatus 0x%02x (seg status %u)\n",
2311		xfer, wa_xfer_id(xfer), seg_idx, usb_status, seg->status);
2312	if (seg->status == WA_SEG_ABORTED
2313	    || seg->status == WA_SEG_ERROR)	/* already handled */
2314		goto segment_aborted;
2315	if (seg->status == WA_SEG_SUBMITTED)	/* ops, got here */
2316		seg->status = WA_SEG_PENDING;	/* before wa_seg{_dto}_cb() */
2317	if (seg->status != WA_SEG_PENDING) {
2318		if (printk_ratelimit())
2319			dev_err(dev, "xfer %p#%u: Bad segment state %u\n",
2320				xfer, seg_idx, seg->status);
2321		seg->status = WA_SEG_PENDING;	/* workaround/"fix" it */
2322	}
2323	if (usb_status & 0x80) {
2324		seg->result = wa_xfer_status_to_errno(usb_status);
2325		dev_err(dev, "DTI: xfer %p 0x%08X:#%u failed (0x%02x)\n",
2326			xfer, xfer->id, seg->index, usb_status);
2327		seg->status = ((usb_status & 0x7F) == WA_XFER_STATUS_ABORTED) ?
2328			WA_SEG_ABORTED : WA_SEG_ERROR;
2329		goto error_complete;
2330	}
2331	/* FIXME: we ignore warnings, tally them for stats */
2332	if (usb_status & 0x40) 		/* Warning?... */
2333		usb_status = 0;		/* ... pass */
2334	/*
2335	 * If the last segment bit is set, complete the remaining segments.
2336	 * When the current segment is completed, either in wa_buf_in_cb for
2337	 * transfers with data or below for no data, the xfer will complete.
2338	 */
2339	if (xfer_result->bTransferSegment & 0x80)
2340		wa_complete_remaining_xfer_segs(xfer, seg->index + 1,
2341			WA_SEG_DONE);
2342	if (usb_pipeisoc(xfer->urb->pipe)
2343		&& (le32_to_cpu(xfer_result->dwNumOfPackets) > 0)) {
2344		/* set up WA state to read the isoc packet status next. */
2345		wa->dti_isoc_xfer_in_progress = wa_xfer_id(xfer);
2346		wa->dti_isoc_xfer_seg = seg_idx;
2347		wa->dti_state = WA_DTI_ISOC_PACKET_STATUS_PENDING;
2348	} else if (xfer->is_inbound && !usb_pipeisoc(xfer->urb->pipe)
2349			&& (bytes_transferred > 0)) {
2350		/* IN data phase: read to buffer */
2351		seg->status = WA_SEG_DTI_PENDING;
2352		result = wa_populate_buf_in_urb(buf_in_urb, xfer, seg_idx,
2353			bytes_transferred);
2354		if (result < 0)
2355			goto error_buf_in_populate;
2356		++(wa->active_buf_in_urbs);
2357		result = usb_submit_urb(buf_in_urb, GFP_ATOMIC);
2358		if (result < 0) {
2359			--(wa->active_buf_in_urbs);
2360			goto error_submit_buf_in;
2361		}
2362	} else {
2363		/* OUT data phase or no data, complete it -- */
2364		seg->result = bytes_transferred;
2365		rpipe_ready = rpipe_avail_inc(rpipe);
2366		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_DONE);
2367	}
2368	spin_unlock_irqrestore(&xfer->lock, flags);
2369	if (done)
2370		wa_xfer_completion(xfer);
2371	if (rpipe_ready)
2372		wa_xfer_delayed_run(rpipe);
2373	return;
2374
2375error_submit_buf_in:
2376	if (edc_inc(&wa->dti_edc, EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
2377		dev_err(dev, "DTI: URB max acceptable errors "
2378			"exceeded, resetting device\n");
2379		wa_reset_all(wa);
2380	}
2381	if (printk_ratelimit())
2382		dev_err(dev, "xfer %p#%u: can't submit DTI data phase: %d\n",
2383			xfer, seg_idx, result);
2384	seg->result = result;
2385	kfree(buf_in_urb->sg);
2386	buf_in_urb->sg = NULL;
2387error_buf_in_populate:
2388	__wa_xfer_abort(xfer);
2389	seg->status = WA_SEG_ERROR;
2390error_complete:
2391	xfer->segs_done++;
2392	rpipe_ready = rpipe_avail_inc(rpipe);
2393	wa_complete_remaining_xfer_segs(xfer, seg->index + 1, seg->status);
2394	done = __wa_xfer_is_done(xfer);
2395	/*
2396	 * queue work item to clear STALL for control endpoints.
2397	 * Otherwise, let endpoint_reset take care of it.
2398	 */
2399	if (((usb_status & 0x3f) == WA_XFER_STATUS_HALTED) &&
2400		usb_endpoint_xfer_control(&xfer->ep->desc) &&
2401		done) {
2402
2403		dev_info(dev, "Control EP stall.  Queue delayed work.\n");
2404		spin_lock(&wa->xfer_list_lock);
2405		/* move xfer from xfer_list to xfer_errored_list. */
2406		list_move_tail(&xfer->list_node, &wa->xfer_errored_list);
2407		spin_unlock(&wa->xfer_list_lock);
2408		spin_unlock_irqrestore(&xfer->lock, flags);
2409		queue_work(wusbd, &wa->xfer_error_work);
2410	} else {
2411		spin_unlock_irqrestore(&xfer->lock, flags);
2412		if (done)
2413			wa_xfer_completion(xfer);
2414		if (rpipe_ready)
2415			wa_xfer_delayed_run(rpipe);
2416	}
2417
2418	return;
2419
2420error_bad_seg:
2421	spin_unlock_irqrestore(&xfer->lock, flags);
2422	wa_urb_dequeue(wa, xfer->urb, -ENOENT);
2423	if (printk_ratelimit())
2424		dev_err(dev, "xfer %p#%u: bad segment\n", xfer, seg_idx);
2425	if (edc_inc(&wa->dti_edc, EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
2426		dev_err(dev, "DTI: URB max acceptable errors "
2427			"exceeded, resetting device\n");
2428		wa_reset_all(wa);
2429	}
2430	return;
2431
2432segment_aborted:
2433	/* nothing to do, as the aborter did the completion */
2434	spin_unlock_irqrestore(&xfer->lock, flags);
2435}
2436
2437/*
2438 * Process a isochronous packet status message
2439 *
2440 * inbound transfers: need to schedule a buf_in_urb read
2441 */
2442static int wa_process_iso_packet_status(struct wahc *wa, struct urb *urb)
2443{
2444	struct device *dev = &wa->usb_iface->dev;
2445	struct wa_xfer_packet_status_hwaiso *packet_status;
2446	struct wa_xfer_packet_status_len_hwaiso *status_array;
2447	struct wa_xfer *xfer;
2448	unsigned long flags;
2449	struct wa_seg *seg;
2450	struct wa_rpipe *rpipe;
2451	unsigned done = 0, dti_busy = 0, data_frame_count = 0, seg_index;
2452	unsigned first_frame_index = 0, rpipe_ready = 0;
2453	int expected_size;
2454
2455	/* We have a xfer result buffer; check it */
2456	dev_dbg(dev, "DTI: isoc packet status %d bytes at %p\n",
2457		urb->actual_length, urb->transfer_buffer);
2458	packet_status = (struct wa_xfer_packet_status_hwaiso *)(wa->dti_buf);
2459	if (packet_status->bPacketType != WA_XFER_ISO_PACKET_STATUS) {
2460		dev_err(dev, "DTI Error: isoc packet status--bad type 0x%02x\n",
2461			packet_status->bPacketType);
2462		goto error_parse_buffer;
2463	}
2464	xfer = wa_xfer_get_by_id(wa, wa->dti_isoc_xfer_in_progress);
2465	if (xfer == NULL) {
2466		dev_err(dev, "DTI Error: isoc packet status--unknown xfer 0x%08x\n",
2467			wa->dti_isoc_xfer_in_progress);
2468		goto error_parse_buffer;
2469	}
2470	spin_lock_irqsave(&xfer->lock, flags);
2471	if (unlikely(wa->dti_isoc_xfer_seg >= xfer->segs))
2472		goto error_bad_seg;
2473	seg = xfer->seg[wa->dti_isoc_xfer_seg];
2474	rpipe = xfer->ep->hcpriv;
2475	expected_size = sizeof(*packet_status) +
2476			(sizeof(packet_status->PacketStatus[0]) *
2477			seg->isoc_frame_count);
2478	if (urb->actual_length != expected_size) {
2479		dev_err(dev, "DTI Error: isoc packet status--bad urb length (%d bytes vs %d needed)\n",
2480			urb->actual_length, expected_size);
2481		goto error_bad_seg;
2482	}
2483	if (le16_to_cpu(packet_status->wLength) != expected_size) {
2484		dev_err(dev, "DTI Error: isoc packet status--bad length %u\n",
2485			le16_to_cpu(packet_status->wLength));
2486		goto error_bad_seg;
2487	}
2488	/* write isoc packet status and lengths back to the xfer urb. */
2489	status_array = packet_status->PacketStatus;
2490	xfer->urb->start_frame =
2491		wa->wusb->usb_hcd.driver->get_frame_number(&wa->wusb->usb_hcd);
2492	for (seg_index = 0; seg_index < seg->isoc_frame_count; ++seg_index) {
2493		struct usb_iso_packet_descriptor *iso_frame_desc =
2494			xfer->urb->iso_frame_desc;
2495		const int xfer_frame_index =
2496			seg->isoc_frame_offset + seg_index;
2497
2498		iso_frame_desc[xfer_frame_index].status =
2499			wa_xfer_status_to_errno(
2500			le16_to_cpu(status_array[seg_index].PacketStatus));
2501		iso_frame_desc[xfer_frame_index].actual_length =
2502			le16_to_cpu(status_array[seg_index].PacketLength);
2503		/* track the number of frames successfully transferred. */
2504		if (iso_frame_desc[xfer_frame_index].actual_length > 0) {
2505			/* save the starting frame index for buf_in_urb. */
2506			if (!data_frame_count)
2507				first_frame_index = seg_index;
2508			++data_frame_count;
2509		}
2510	}
2511
2512	if (xfer->is_inbound && data_frame_count) {
2513		int result, total_frames_read = 0, urb_index = 0;
2514		struct urb *buf_in_urb;
2515
2516		/* IN data phase: read to buffer */
2517		seg->status = WA_SEG_DTI_PENDING;
2518
2519		/* start with the first frame with data. */
2520		seg->isoc_frame_index = first_frame_index;
2521		/* submit up to WA_MAX_BUF_IN_URBS read URBs. */
2522		do {
2523			int urb_frame_index, urb_frame_count;
2524			struct usb_iso_packet_descriptor *iso_frame_desc;
2525
2526			buf_in_urb = &(wa->buf_in_urbs[urb_index]);
2527			urb_frame_count = __wa_populate_buf_in_urb_isoc(wa,
2528				buf_in_urb, xfer, seg);
2529			/* advance frame index to start of next read URB. */
2530			seg->isoc_frame_index += urb_frame_count;
2531			total_frames_read += urb_frame_count;
2532
2533			++(wa->active_buf_in_urbs);
2534			result = usb_submit_urb(buf_in_urb, GFP_ATOMIC);
2535
2536			/* skip 0-byte frames. */
2537			urb_frame_index =
2538				seg->isoc_frame_offset + seg->isoc_frame_index;
2539			iso_frame_desc =
2540				&(xfer->urb->iso_frame_desc[urb_frame_index]);
2541			while ((seg->isoc_frame_index <
2542						seg->isoc_frame_count) &&
2543				 (iso_frame_desc->actual_length == 0)) {
2544				++(seg->isoc_frame_index);
2545				++iso_frame_desc;
2546			}
2547			++urb_index;
2548
2549		} while ((result == 0) && (urb_index < WA_MAX_BUF_IN_URBS)
2550				&& (seg->isoc_frame_index <
2551						seg->isoc_frame_count));
2552
2553		if (result < 0) {
2554			--(wa->active_buf_in_urbs);
2555			dev_err(dev, "DTI Error: Could not submit buf in URB (%d)",
2556				result);
2557			wa_reset_all(wa);
2558		} else if (data_frame_count > total_frames_read)
2559			/* If we need to read more frames, set DTI busy. */
2560			dti_busy = 1;
2561	} else {
2562		/* OUT transfer or no more IN data, complete it -- */
2563		rpipe_ready = rpipe_avail_inc(rpipe);
2564		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_DONE);
2565	}
2566	spin_unlock_irqrestore(&xfer->lock, flags);
2567	if (dti_busy)
2568		wa->dti_state = WA_DTI_BUF_IN_DATA_PENDING;
2569	else
2570		wa->dti_state = WA_DTI_TRANSFER_RESULT_PENDING;
2571	if (done)
2572		wa_xfer_completion(xfer);
2573	if (rpipe_ready)
2574		wa_xfer_delayed_run(rpipe);
2575	wa_xfer_put(xfer);
2576	return dti_busy;
2577
2578error_bad_seg:
2579	spin_unlock_irqrestore(&xfer->lock, flags);
2580	wa_xfer_put(xfer);
2581error_parse_buffer:
2582	return dti_busy;
2583}
2584
2585/*
2586 * Callback for the IN data phase
2587 *
2588 * If successful transition state; otherwise, take a note of the
2589 * error, mark this segment done and try completion.
2590 *
2591 * Note we don't access until we are sure that the transfer hasn't
2592 * been cancelled (ECONNRESET, ENOENT), which could mean that
2593 * seg->xfer could be already gone.
2594 */
2595static void wa_buf_in_cb(struct urb *urb)
2596{
2597	struct wa_seg *seg = urb->context;
2598	struct wa_xfer *xfer = seg->xfer;
2599	struct wahc *wa;
2600	struct device *dev;
2601	struct wa_rpipe *rpipe;
2602	unsigned rpipe_ready = 0, isoc_data_frame_count = 0;
2603	unsigned long flags;
2604	int resubmit_dti = 0, active_buf_in_urbs;
2605	u8 done = 0;
2606
2607	/* free the sg if it was used. */
2608	kfree(urb->sg);
2609	urb->sg = NULL;
2610
2611	spin_lock_irqsave(&xfer->lock, flags);
2612	wa = xfer->wa;
2613	dev = &wa->usb_iface->dev;
2614	--(wa->active_buf_in_urbs);
2615	active_buf_in_urbs = wa->active_buf_in_urbs;
2616	rpipe = xfer->ep->hcpriv;
2617
2618	if (usb_pipeisoc(xfer->urb->pipe)) {
2619		struct usb_iso_packet_descriptor *iso_frame_desc =
2620			xfer->urb->iso_frame_desc;
2621		int	seg_index;
2622
2623		/*
2624		 * Find the next isoc frame with data and count how many
2625		 * frames with data remain.
2626		 */
2627		seg_index = seg->isoc_frame_index;
2628		while (seg_index < seg->isoc_frame_count) {
2629			const int urb_frame_index =
2630				seg->isoc_frame_offset + seg_index;
2631
2632			if (iso_frame_desc[urb_frame_index].actual_length > 0) {
2633				/* save the index of the next frame with data */
2634				if (!isoc_data_frame_count)
2635					seg->isoc_frame_index = seg_index;
2636				++isoc_data_frame_count;
2637			}
2638			++seg_index;
2639		}
2640	}
2641	spin_unlock_irqrestore(&xfer->lock, flags);
2642
2643	switch (urb->status) {
2644	case 0:
2645		spin_lock_irqsave(&xfer->lock, flags);
2646
2647		seg->result += urb->actual_length;
2648		if (isoc_data_frame_count > 0) {
2649			int result, urb_frame_count;
2650
2651			/* submit a read URB for the next frame with data. */
2652			urb_frame_count = __wa_populate_buf_in_urb_isoc(wa, urb,
2653				 xfer, seg);
2654			/* advance index to start of next read URB. */
2655			seg->isoc_frame_index += urb_frame_count;
2656			++(wa->active_buf_in_urbs);
2657			result = usb_submit_urb(urb, GFP_ATOMIC);
2658			if (result < 0) {
2659				--(wa->active_buf_in_urbs);
2660				dev_err(dev, "DTI Error: Could not submit buf in URB (%d)",
2661					result);
2662				wa_reset_all(wa);
2663			}
2664			/*
2665			 * If we are in this callback and
2666			 * isoc_data_frame_count > 0, it means that the dti_urb
2667			 * submission was delayed in wa_dti_cb.  Once
2668			 * we submit the last buf_in_urb, we can submit the
2669			 * delayed dti_urb.
2670			 */
2671			  resubmit_dti = (isoc_data_frame_count ==
2672							urb_frame_count);
2673		} else if (active_buf_in_urbs == 0) {
2674			dev_dbg(dev,
2675				"xfer %p 0x%08X#%u: data in done (%zu bytes)\n",
2676				xfer, wa_xfer_id(xfer), seg->index,
2677				seg->result);
2678			rpipe_ready = rpipe_avail_inc(rpipe);
2679			done = __wa_xfer_mark_seg_as_done(xfer, seg,
2680					WA_SEG_DONE);
2681		}
2682		spin_unlock_irqrestore(&xfer->lock, flags);
2683		if (done)
2684			wa_xfer_completion(xfer);
2685		if (rpipe_ready)
2686			wa_xfer_delayed_run(rpipe);
2687		break;
2688	case -ECONNRESET:	/* URB unlinked; no need to do anything */
2689	case -ENOENT:		/* as it was done by the who unlinked us */
2690		break;
2691	default:		/* Other errors ... */
2692		/*
2693		 * Error on data buf read.  Only resubmit DTI if it hasn't
2694		 * already been done by previously hitting this error or by a
2695		 * successful completion of the previous buf_in_urb.
2696		 */
2697		resubmit_dti = wa->dti_state != WA_DTI_TRANSFER_RESULT_PENDING;
2698		spin_lock_irqsave(&xfer->lock, flags);
2699		if (printk_ratelimit())
2700			dev_err(dev, "xfer %p 0x%08X#%u: data in error %d\n",
2701				xfer, wa_xfer_id(xfer), seg->index,
2702				urb->status);
2703		if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
2704			    EDC_ERROR_TIMEFRAME)){
2705			dev_err(dev, "DTO: URB max acceptable errors "
2706				"exceeded, resetting device\n");
2707			wa_reset_all(wa);
2708		}
2709		seg->result = urb->status;
2710		rpipe_ready = rpipe_avail_inc(rpipe);
2711		if (active_buf_in_urbs == 0)
2712			done = __wa_xfer_mark_seg_as_done(xfer, seg,
2713				WA_SEG_ERROR);
2714		else
2715			__wa_xfer_abort(xfer);
2716		spin_unlock_irqrestore(&xfer->lock, flags);
2717		if (done)
2718			wa_xfer_completion(xfer);
2719		if (rpipe_ready)
2720			wa_xfer_delayed_run(rpipe);
2721	}
2722
2723	if (resubmit_dti) {
2724		int result;
2725
2726		wa->dti_state = WA_DTI_TRANSFER_RESULT_PENDING;
2727
2728		result = usb_submit_urb(wa->dti_urb, GFP_ATOMIC);
2729		if (result < 0) {
2730			dev_err(dev, "DTI Error: Could not submit DTI URB (%d)\n",
2731				result);
2732			wa_reset_all(wa);
2733		}
2734	}
2735}
2736
2737/*
2738 * Handle an incoming transfer result buffer
2739 *
2740 * Given a transfer result buffer, it completes the transfer (possibly
2741 * scheduling and buffer in read) and then resubmits the DTI URB for a
2742 * new transfer result read.
2743 *
2744 *
2745 * The xfer_result DTI URB state machine
2746 *
2747 * States: OFF | RXR (Read-Xfer-Result) | RBI (Read-Buffer-In)
2748 *
2749 * We start in OFF mode, the first xfer_result notification [through
2750 * wa_handle_notif_xfer()] moves us to RXR by posting the DTI-URB to
2751 * read.
2752 *
2753 * We receive a buffer -- if it is not a xfer_result, we complain and
2754 * repost the DTI-URB. If it is a xfer_result then do the xfer seg
2755 * request accounting. If it is an IN segment, we move to RBI and post
2756 * a BUF-IN-URB to the right buffer. The BUF-IN-URB callback will
2757 * repost the DTI-URB and move to RXR state. if there was no IN
2758 * segment, it will repost the DTI-URB.
2759 *
2760 * We go back to OFF when we detect a ENOENT or ESHUTDOWN (or too many
2761 * errors) in the URBs.
2762 */
2763static void wa_dti_cb(struct urb *urb)
2764{
2765	int result, dti_busy = 0;
2766	struct wahc *wa = urb->context;
2767	struct device *dev = &wa->usb_iface->dev;
2768	u32 xfer_id;
2769	u8 usb_status;
2770
2771	BUG_ON(wa->dti_urb != urb);
2772	switch (wa->dti_urb->status) {
2773	case 0:
2774		if (wa->dti_state == WA_DTI_TRANSFER_RESULT_PENDING) {
2775			struct wa_xfer_result *xfer_result;
2776			struct wa_xfer *xfer;
2777
2778			/* We have a xfer result buffer; check it */
2779			dev_dbg(dev, "DTI: xfer result %d bytes at %p\n",
2780				urb->actual_length, urb->transfer_buffer);
2781			if (urb->actual_length != sizeof(*xfer_result)) {
2782				dev_err(dev, "DTI Error: xfer result--bad size xfer result (%d bytes vs %zu needed)\n",
2783					urb->actual_length,
2784					sizeof(*xfer_result));
2785				break;
2786			}
2787			xfer_result = (struct wa_xfer_result *)(wa->dti_buf);
2788			if (xfer_result->hdr.bLength != sizeof(*xfer_result)) {
2789				dev_err(dev, "DTI Error: xfer result--bad header length %u\n",
2790					xfer_result->hdr.bLength);
2791				break;
2792			}
2793			if (xfer_result->hdr.bNotifyType != WA_XFER_RESULT) {
2794				dev_err(dev, "DTI Error: xfer result--bad header type 0x%02x\n",
2795					xfer_result->hdr.bNotifyType);
2796				break;
2797			}
2798			xfer_id = le32_to_cpu(xfer_result->dwTransferID);
2799			usb_status = xfer_result->bTransferStatus & 0x3f;
2800			if (usb_status == WA_XFER_STATUS_NOT_FOUND) {
2801				/* taken care of already */
2802				dev_dbg(dev, "%s: xfer 0x%08X#%u not found.\n",
2803					__func__, xfer_id,
2804					xfer_result->bTransferSegment & 0x7f);
2805				break;
2806			}
2807			xfer = wa_xfer_get_by_id(wa, xfer_id);
2808			if (xfer == NULL) {
2809				/* FIXME: transaction not found. */
2810				dev_err(dev, "DTI Error: xfer result--unknown xfer 0x%08x (status 0x%02x)\n",
2811					xfer_id, usb_status);
2812				break;
2813			}
2814			wa_xfer_result_chew(wa, xfer, xfer_result);
2815			wa_xfer_put(xfer);
2816		} else if (wa->dti_state == WA_DTI_ISOC_PACKET_STATUS_PENDING) {
2817			dti_busy = wa_process_iso_packet_status(wa, urb);
2818		} else {
2819			dev_err(dev, "DTI Error: unexpected EP state = %d\n",
2820				wa->dti_state);
2821		}
2822		break;
2823	case -ENOENT:		/* (we killed the URB)...so, no broadcast */
2824	case -ESHUTDOWN:	/* going away! */
2825		dev_dbg(dev, "DTI: going down! %d\n", urb->status);
2826		goto out;
2827	default:
2828		/* Unknown error */
2829		if (edc_inc(&wa->dti_edc, EDC_MAX_ERRORS,
2830			    EDC_ERROR_TIMEFRAME)) {
2831			dev_err(dev, "DTI: URB max acceptable errors "
2832				"exceeded, resetting device\n");
2833			wa_reset_all(wa);
2834			goto out;
2835		}
2836		if (printk_ratelimit())
2837			dev_err(dev, "DTI: URB error %d\n", urb->status);
2838		break;
2839	}
2840
2841	/* Resubmit the DTI URB if we are not busy processing isoc in frames. */
2842	if (!dti_busy) {
2843		result = usb_submit_urb(wa->dti_urb, GFP_ATOMIC);
2844		if (result < 0) {
2845			dev_err(dev, "DTI Error: Could not submit DTI URB (%d)\n",
2846				result);
2847			wa_reset_all(wa);
2848		}
2849	}
2850out:
2851	return;
2852}
2853
2854/*
2855 * Initialize the DTI URB for reading transfer result notifications and also
2856 * the buffer-in URB, for reading buffers. Then we just submit the DTI URB.
2857 */
2858int wa_dti_start(struct wahc *wa)
2859{
2860	const struct usb_endpoint_descriptor *dti_epd = wa->dti_epd;
2861	struct device *dev = &wa->usb_iface->dev;
2862	int result = -ENOMEM, index;
2863
2864	if (wa->dti_urb != NULL)	/* DTI URB already started */
2865		goto out;
2866
2867	wa->dti_urb = usb_alloc_urb(0, GFP_KERNEL);
2868	if (wa->dti_urb == NULL) {
2869		dev_err(dev, "Can't allocate DTI URB\n");
2870		goto error_dti_urb_alloc;
2871	}
2872	usb_fill_bulk_urb(
2873		wa->dti_urb, wa->usb_dev,
2874		usb_rcvbulkpipe(wa->usb_dev, 0x80 | dti_epd->bEndpointAddress),
2875		wa->dti_buf, wa->dti_buf_size,
2876		wa_dti_cb, wa);
2877
2878	/* init the buf in URBs */
2879	for (index = 0; index < WA_MAX_BUF_IN_URBS; ++index) {
2880		usb_fill_bulk_urb(
2881			&(wa->buf_in_urbs[index]), wa->usb_dev,
2882			usb_rcvbulkpipe(wa->usb_dev,
2883				0x80 | dti_epd->bEndpointAddress),
2884			NULL, 0, wa_buf_in_cb, wa);
2885	}
2886	result = usb_submit_urb(wa->dti_urb, GFP_KERNEL);
2887	if (result < 0) {
2888		dev_err(dev, "DTI Error: Could not submit DTI URB (%d) resetting\n",
2889			result);
2890		goto error_dti_urb_submit;
2891	}
2892out:
2893	return 0;
2894
2895error_dti_urb_submit:
2896	usb_put_urb(wa->dti_urb);
2897	wa->dti_urb = NULL;
2898error_dti_urb_alloc:
2899	return result;
2900}
2901EXPORT_SYMBOL_GPL(wa_dti_start);
2902/*
2903 * Transfer complete notification
2904 *
2905 * Called from the notif.c code. We get a notification on EP2 saying
2906 * that some endpoint has some transfer result data available. We are
2907 * about to read it.
2908 *
2909 * To speed up things, we always have a URB reading the DTI URB; we
2910 * don't really set it up and start it until the first xfer complete
2911 * notification arrives, which is what we do here.
2912 *
2913 * Follow up in wa_dti_cb(), as that's where the whole state
2914 * machine starts.
2915 *
2916 * @wa shall be referenced
2917 */
2918void wa_handle_notif_xfer(struct wahc *wa, struct wa_notif_hdr *notif_hdr)
2919{
2920	struct device *dev = &wa->usb_iface->dev;
2921	struct wa_notif_xfer *notif_xfer;
2922	const struct usb_endpoint_descriptor *dti_epd = wa->dti_epd;
2923
2924	notif_xfer = container_of(notif_hdr, struct wa_notif_xfer, hdr);
2925	BUG_ON(notif_hdr->bNotifyType != WA_NOTIF_TRANSFER);
2926
2927	if ((0x80 | notif_xfer->bEndpoint) != dti_epd->bEndpointAddress) {
2928		/* FIXME: hardcoded limitation, adapt */
2929		dev_err(dev, "BUG: DTI ep is %u, not %u (hack me)\n",
2930			notif_xfer->bEndpoint, dti_epd->bEndpointAddress);
2931		goto error;
2932	}
2933
2934	/* attempt to start the DTI ep processing. */
2935	if (wa_dti_start(wa) < 0)
2936		goto error;
2937
2938	return;
2939
2940error:
2941	wa_reset_all(wa);
2942}
v4.17
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * WUSB Wire Adapter
   4 * Data transfer and URB enqueing
   5 *
   6 * Copyright (C) 2005-2006 Intel Corporation
   7 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
   8 *
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   9 * How transfers work: get a buffer, break it up in segments (segment
  10 * size is a multiple of the maxpacket size). For each segment issue a
  11 * segment request (struct wa_xfer_*), then send the data buffer if
  12 * out or nothing if in (all over the DTO endpoint).
  13 *
  14 * For each submitted segment request, a notification will come over
  15 * the NEP endpoint and a transfer result (struct xfer_result) will
  16 * arrive in the DTI URB. Read it, get the xfer ID, see if there is
  17 * data coming (inbound transfer), schedule a read and handle it.
  18 *
  19 * Sounds simple, it is a pain to implement.
  20 *
  21 *
  22 * ENTRY POINTS
  23 *
  24 *   FIXME
  25 *
  26 * LIFE CYCLE / STATE DIAGRAM
  27 *
  28 *   FIXME
  29 *
  30 * THIS CODE IS DISGUSTING
  31 *
  32 *   Warned you are; it's my second try and still not happy with it.
  33 *
  34 * NOTES:
  35 *
  36 *   - No iso
  37 *
  38 *   - Supports DMA xfers, control, bulk and maybe interrupt
  39 *
  40 *   - Does not recycle unused rpipes
  41 *
  42 *     An rpipe is assigned to an endpoint the first time it is used,
  43 *     and then it's there, assigned, until the endpoint is disabled
  44 *     (destroyed [{h,d}wahc_op_ep_disable()]. The assignment of the
  45 *     rpipe to the endpoint is done under the wa->rpipe_sem semaphore
  46 *     (should be a mutex).
  47 *
  48 *     Two methods it could be done:
  49 *
  50 *     (a) set up a timer every time an rpipe's use count drops to 1
  51 *         (which means unused) or when a transfer ends. Reset the
  52 *         timer when a xfer is queued. If the timer expires, release
  53 *         the rpipe [see rpipe_ep_disable()].
  54 *
  55 *     (b) when looking for free rpipes to attach [rpipe_get_by_ep()],
  56 *         when none are found go over the list, check their endpoint
  57 *         and their activity record (if no last-xfer-done-ts in the
  58 *         last x seconds) take it
  59 *
  60 *     However, due to the fact that we have a set of limited
  61 *     resources (max-segments-at-the-same-time per xfer,
  62 *     xfers-per-ripe, blocks-per-rpipe, rpipes-per-host), at the end
  63 *     we are going to have to rebuild all this based on an scheduler,
  64 *     to where we have a list of transactions to do and based on the
  65 *     availability of the different required components (blocks,
  66 *     rpipes, segment slots, etc), we go scheduling them. Painful.
  67 */
  68#include <linux/spinlock.h>
  69#include <linux/slab.h>
  70#include <linux/hash.h>
  71#include <linux/ratelimit.h>
  72#include <linux/export.h>
  73#include <linux/scatterlist.h>
  74
  75#include "wa-hc.h"
  76#include "wusbhc.h"
  77
  78enum {
  79	/* [WUSB] section 8.3.3 allocates 7 bits for the segment index. */
  80	WA_SEGS_MAX = 128,
  81};
  82
  83enum wa_seg_status {
  84	WA_SEG_NOTREADY,
  85	WA_SEG_READY,
  86	WA_SEG_DELAYED,
  87	WA_SEG_SUBMITTED,
  88	WA_SEG_PENDING,
  89	WA_SEG_DTI_PENDING,
  90	WA_SEG_DONE,
  91	WA_SEG_ERROR,
  92	WA_SEG_ABORTED,
  93};
  94
  95static void wa_xfer_delayed_run(struct wa_rpipe *);
  96static int __wa_xfer_delayed_run(struct wa_rpipe *rpipe, int *dto_waiting);
  97
  98/*
  99 * Life cycle governed by 'struct urb' (the refcount of the struct is
 100 * that of the 'struct urb' and usb_free_urb() would free the whole
 101 * struct).
 102 */
 103struct wa_seg {
 104	struct urb tr_urb;		/* transfer request urb. */
 105	struct urb *isoc_pack_desc_urb;	/* for isoc packet descriptor. */
 106	struct urb *dto_urb;		/* for data output. */
 107	struct list_head list_node;	/* for rpipe->req_list */
 108	struct wa_xfer *xfer;		/* out xfer */
 109	u8 index;			/* which segment we are */
 110	int isoc_frame_count;	/* number of isoc frames in this segment. */
 111	int isoc_frame_offset;	/* starting frame offset in the xfer URB. */
 112	/* Isoc frame that the current transfer buffer corresponds to. */
 113	int isoc_frame_index;
 114	int isoc_size;	/* size of all isoc frames sent by this seg. */
 115	enum wa_seg_status status;
 116	ssize_t result;			/* bytes xfered or error */
 117	struct wa_xfer_hdr xfer_hdr;
 118};
 119
 120static inline void wa_seg_init(struct wa_seg *seg)
 121{
 122	usb_init_urb(&seg->tr_urb);
 123
 124	/* set the remaining memory to 0. */
 125	memset(((void *)seg) + sizeof(seg->tr_urb), 0,
 126		sizeof(*seg) - sizeof(seg->tr_urb));
 127}
 128
 129/*
 130 * Protected by xfer->lock
 131 *
 132 */
 133struct wa_xfer {
 134	struct kref refcnt;
 135	struct list_head list_node;
 136	spinlock_t lock;
 137	u32 id;
 138
 139	struct wahc *wa;		/* Wire adapter we are plugged to */
 140	struct usb_host_endpoint *ep;
 141	struct urb *urb;		/* URB we are transferring for */
 142	struct wa_seg **seg;		/* transfer segments */
 143	u8 segs, segs_submitted, segs_done;
 144	unsigned is_inbound:1;
 145	unsigned is_dma:1;
 146	size_t seg_size;
 147	int result;
 148
 149	gfp_t gfp;			/* allocation mask */
 150
 151	struct wusb_dev *wusb_dev;	/* for activity timestamps */
 152};
 153
 154static void __wa_populate_dto_urb_isoc(struct wa_xfer *xfer,
 155	struct wa_seg *seg, int curr_iso_frame);
 156static void wa_complete_remaining_xfer_segs(struct wa_xfer *xfer,
 157		int starting_index, enum wa_seg_status status);
 158
 159static inline void wa_xfer_init(struct wa_xfer *xfer)
 160{
 161	kref_init(&xfer->refcnt);
 162	INIT_LIST_HEAD(&xfer->list_node);
 163	spin_lock_init(&xfer->lock);
 164}
 165
 166/*
 167 * Destroy a transfer structure
 168 *
 169 * Note that freeing xfer->seg[cnt]->tr_urb will free the containing
 170 * xfer->seg[cnt] memory that was allocated by __wa_xfer_setup_segs.
 171 */
 172static void wa_xfer_destroy(struct kref *_xfer)
 173{
 174	struct wa_xfer *xfer = container_of(_xfer, struct wa_xfer, refcnt);
 175	if (xfer->seg) {
 176		unsigned cnt;
 177		for (cnt = 0; cnt < xfer->segs; cnt++) {
 178			struct wa_seg *seg = xfer->seg[cnt];
 179			if (seg) {
 180				usb_free_urb(seg->isoc_pack_desc_urb);
 181				if (seg->dto_urb) {
 182					kfree(seg->dto_urb->sg);
 183					usb_free_urb(seg->dto_urb);
 184				}
 185				usb_free_urb(&seg->tr_urb);
 186			}
 187		}
 188		kfree(xfer->seg);
 189	}
 190	kfree(xfer);
 191}
 192
 193static void wa_xfer_get(struct wa_xfer *xfer)
 194{
 195	kref_get(&xfer->refcnt);
 196}
 197
 198static void wa_xfer_put(struct wa_xfer *xfer)
 199{
 200	kref_put(&xfer->refcnt, wa_xfer_destroy);
 201}
 202
 203/*
 204 * Try to get exclusive access to the DTO endpoint resource.  Return true
 205 * if successful.
 206 */
 207static inline int __wa_dto_try_get(struct wahc *wa)
 208{
 209	return (test_and_set_bit(0, &wa->dto_in_use) == 0);
 210}
 211
 212/* Release the DTO endpoint resource. */
 213static inline void __wa_dto_put(struct wahc *wa)
 214{
 215	clear_bit_unlock(0, &wa->dto_in_use);
 216}
 217
 218/* Service RPIPEs that are waiting on the DTO resource. */
 219static void wa_check_for_delayed_rpipes(struct wahc *wa)
 220{
 221	unsigned long flags;
 222	int dto_waiting = 0;
 223	struct wa_rpipe *rpipe;
 224
 225	spin_lock_irqsave(&wa->rpipe_lock, flags);
 226	while (!list_empty(&wa->rpipe_delayed_list) && !dto_waiting) {
 227		rpipe = list_first_entry(&wa->rpipe_delayed_list,
 228				struct wa_rpipe, list_node);
 229		__wa_xfer_delayed_run(rpipe, &dto_waiting);
 230		/* remove this RPIPE from the list if it is not waiting. */
 231		if (!dto_waiting) {
 232			pr_debug("%s: RPIPE %d serviced and removed from delayed list.\n",
 233				__func__,
 234				le16_to_cpu(rpipe->descr.wRPipeIndex));
 235			list_del_init(&rpipe->list_node);
 236		}
 237	}
 238	spin_unlock_irqrestore(&wa->rpipe_lock, flags);
 239}
 240
 241/* add this RPIPE to the end of the delayed RPIPE list. */
 242static void wa_add_delayed_rpipe(struct wahc *wa, struct wa_rpipe *rpipe)
 243{
 244	unsigned long flags;
 245
 246	spin_lock_irqsave(&wa->rpipe_lock, flags);
 247	/* add rpipe to the list if it is not already on it. */
 248	if (list_empty(&rpipe->list_node)) {
 249		pr_debug("%s: adding RPIPE %d to the delayed list.\n",
 250			__func__, le16_to_cpu(rpipe->descr.wRPipeIndex));
 251		list_add_tail(&rpipe->list_node, &wa->rpipe_delayed_list);
 252	}
 253	spin_unlock_irqrestore(&wa->rpipe_lock, flags);
 254}
 255
 256/*
 257 * xfer is referenced
 258 *
 259 * xfer->lock has to be unlocked
 260 *
 261 * We take xfer->lock for setting the result; this is a barrier
 262 * against drivers/usb/core/hcd.c:unlink1() being called after we call
 263 * usb_hcd_giveback_urb() and wa_urb_dequeue() trying to get a
 264 * reference to the transfer.
 265 */
 266static void wa_xfer_giveback(struct wa_xfer *xfer)
 267{
 268	unsigned long flags;
 269
 270	spin_lock_irqsave(&xfer->wa->xfer_list_lock, flags);
 271	list_del_init(&xfer->list_node);
 272	usb_hcd_unlink_urb_from_ep(&(xfer->wa->wusb->usb_hcd), xfer->urb);
 273	spin_unlock_irqrestore(&xfer->wa->xfer_list_lock, flags);
 274	/* FIXME: segmentation broken -- kills DWA */
 275	wusbhc_giveback_urb(xfer->wa->wusb, xfer->urb, xfer->result);
 276	wa_put(xfer->wa);
 277	wa_xfer_put(xfer);
 278}
 279
 280/*
 281 * xfer is referenced
 282 *
 283 * xfer->lock has to be unlocked
 284 */
 285static void wa_xfer_completion(struct wa_xfer *xfer)
 286{
 287	if (xfer->wusb_dev)
 288		wusb_dev_put(xfer->wusb_dev);
 289	rpipe_put(xfer->ep->hcpriv);
 290	wa_xfer_giveback(xfer);
 291}
 292
 293/*
 294 * Initialize a transfer's ID
 295 *
 296 * We need to use a sequential number; if we use the pointer or the
 297 * hash of the pointer, it can repeat over sequential transfers and
 298 * then it will confuse the HWA....wonder why in hell they put a 32
 299 * bit handle in there then.
 300 */
 301static void wa_xfer_id_init(struct wa_xfer *xfer)
 302{
 303	xfer->id = atomic_add_return(1, &xfer->wa->xfer_id_count);
 304}
 305
 306/* Return the xfer's ID. */
 307static inline u32 wa_xfer_id(struct wa_xfer *xfer)
 308{
 309	return xfer->id;
 310}
 311
 312/* Return the xfer's ID in transport format (little endian). */
 313static inline __le32 wa_xfer_id_le32(struct wa_xfer *xfer)
 314{
 315	return cpu_to_le32(xfer->id);
 316}
 317
 318/*
 319 * If transfer is done, wrap it up and return true
 320 *
 321 * xfer->lock has to be locked
 322 */
 323static unsigned __wa_xfer_is_done(struct wa_xfer *xfer)
 324{
 325	struct device *dev = &xfer->wa->usb_iface->dev;
 326	unsigned result, cnt;
 327	struct wa_seg *seg;
 328	struct urb *urb = xfer->urb;
 329	unsigned found_short = 0;
 330
 331	result = xfer->segs_done == xfer->segs_submitted;
 332	if (result == 0)
 333		goto out;
 334	urb->actual_length = 0;
 335	for (cnt = 0; cnt < xfer->segs; cnt++) {
 336		seg = xfer->seg[cnt];
 337		switch (seg->status) {
 338		case WA_SEG_DONE:
 339			if (found_short && seg->result > 0) {
 340				dev_dbg(dev, "xfer %p ID %08X#%u: bad short segments (%zu)\n",
 341					xfer, wa_xfer_id(xfer), cnt,
 342					seg->result);
 343				urb->status = -EINVAL;
 344				goto out;
 345			}
 346			urb->actual_length += seg->result;
 347			if (!(usb_pipeisoc(xfer->urb->pipe))
 348				&& seg->result < xfer->seg_size
 349			    && cnt != xfer->segs-1)
 350				found_short = 1;
 351			dev_dbg(dev, "xfer %p ID %08X#%u: DONE short %d "
 352				"result %zu urb->actual_length %d\n",
 353				xfer, wa_xfer_id(xfer), seg->index, found_short,
 354				seg->result, urb->actual_length);
 355			break;
 356		case WA_SEG_ERROR:
 357			xfer->result = seg->result;
 358			dev_dbg(dev, "xfer %p ID %08X#%u: ERROR result %zi(0x%08zX)\n",
 359				xfer, wa_xfer_id(xfer), seg->index, seg->result,
 360				seg->result);
 361			goto out;
 362		case WA_SEG_ABORTED:
 363			xfer->result = seg->result;
 364			dev_dbg(dev, "xfer %p ID %08X#%u: ABORTED result %zi(0x%08zX)\n",
 365				xfer, wa_xfer_id(xfer), seg->index, seg->result,
 366				seg->result);
 367			goto out;
 368		default:
 369			dev_warn(dev, "xfer %p ID %08X#%u: is_done bad state %d\n",
 370				 xfer, wa_xfer_id(xfer), cnt, seg->status);
 371			xfer->result = -EINVAL;
 372			goto out;
 373		}
 374	}
 375	xfer->result = 0;
 376out:
 377	return result;
 378}
 379
 380/*
 381 * Mark the given segment as done.  Return true if this completes the xfer.
 382 * This should only be called for segs that have been submitted to an RPIPE.
 383 * Delayed segs are not marked as submitted so they do not need to be marked
 384 * as done when cleaning up.
 385 *
 386 * xfer->lock has to be locked
 387 */
 388static unsigned __wa_xfer_mark_seg_as_done(struct wa_xfer *xfer,
 389	struct wa_seg *seg, enum wa_seg_status status)
 390{
 391	seg->status = status;
 392	xfer->segs_done++;
 393
 394	/* check for done. */
 395	return __wa_xfer_is_done(xfer);
 396}
 397
 398/*
 399 * Search for a transfer list ID on the HCD's URB list
 400 *
 401 * For 32 bit architectures, we use the pointer itself; for 64 bits, a
 402 * 32-bit hash of the pointer.
 403 *
 404 * @returns NULL if not found.
 405 */
 406static struct wa_xfer *wa_xfer_get_by_id(struct wahc *wa, u32 id)
 407{
 408	unsigned long flags;
 409	struct wa_xfer *xfer_itr;
 410	spin_lock_irqsave(&wa->xfer_list_lock, flags);
 411	list_for_each_entry(xfer_itr, &wa->xfer_list, list_node) {
 412		if (id == xfer_itr->id) {
 413			wa_xfer_get(xfer_itr);
 414			goto out;
 415		}
 416	}
 417	xfer_itr = NULL;
 418out:
 419	spin_unlock_irqrestore(&wa->xfer_list_lock, flags);
 420	return xfer_itr;
 421}
 422
 423struct wa_xfer_abort_buffer {
 424	struct urb urb;
 425	struct wahc *wa;
 426	struct wa_xfer_abort cmd;
 427};
 428
 429static void __wa_xfer_abort_cb(struct urb *urb)
 430{
 431	struct wa_xfer_abort_buffer *b = urb->context;
 432	struct wahc *wa = b->wa;
 433
 434	/*
 435	 * If the abort request URB failed, then the HWA did not get the abort
 436	 * command.  Forcibly clean up the xfer without waiting for a Transfer
 437	 * Result from the HWA.
 438	 */
 439	if (urb->status < 0) {
 440		struct wa_xfer *xfer;
 441		struct device *dev = &wa->usb_iface->dev;
 442
 443		xfer = wa_xfer_get_by_id(wa, le32_to_cpu(b->cmd.dwTransferID));
 444		dev_err(dev, "%s: Transfer Abort request failed. result: %d\n",
 445			__func__, urb->status);
 446		if (xfer) {
 447			unsigned long flags;
 448			int done, seg_index = 0;
 449			struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 450
 451			dev_err(dev, "%s: cleaning up xfer %p ID 0x%08X.\n",
 452				__func__, xfer, wa_xfer_id(xfer));
 453			spin_lock_irqsave(&xfer->lock, flags);
 454			/* skip done segs. */
 455			while (seg_index < xfer->segs) {
 456				struct wa_seg *seg = xfer->seg[seg_index];
 457
 458				if ((seg->status == WA_SEG_DONE) ||
 459					(seg->status == WA_SEG_ERROR)) {
 460					++seg_index;
 461				} else {
 462					break;
 463				}
 464			}
 465			/* mark remaining segs as aborted. */
 466			wa_complete_remaining_xfer_segs(xfer, seg_index,
 467				WA_SEG_ABORTED);
 468			done = __wa_xfer_is_done(xfer);
 469			spin_unlock_irqrestore(&xfer->lock, flags);
 470			if (done)
 471				wa_xfer_completion(xfer);
 472			wa_xfer_delayed_run(rpipe);
 473			wa_xfer_put(xfer);
 474		} else {
 475			dev_err(dev, "%s: xfer ID 0x%08X already gone.\n",
 476				 __func__, le32_to_cpu(b->cmd.dwTransferID));
 477		}
 478	}
 479
 480	wa_put(wa);	/* taken in __wa_xfer_abort */
 481	usb_put_urb(&b->urb);
 482}
 483
 484/*
 485 * Aborts an ongoing transaction
 486 *
 487 * Assumes the transfer is referenced and locked and in a submitted
 488 * state (mainly that there is an endpoint/rpipe assigned).
 489 *
 490 * The callback (see above) does nothing but freeing up the data by
 491 * putting the URB. Because the URB is allocated at the head of the
 492 * struct, the whole space we allocated is kfreed. *
 493 */
 494static int __wa_xfer_abort(struct wa_xfer *xfer)
 495{
 496	int result = -ENOMEM;
 497	struct device *dev = &xfer->wa->usb_iface->dev;
 498	struct wa_xfer_abort_buffer *b;
 499	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 500
 501	b = kmalloc(sizeof(*b), GFP_ATOMIC);
 502	if (b == NULL)
 503		goto error_kmalloc;
 504	b->cmd.bLength =  sizeof(b->cmd);
 505	b->cmd.bRequestType = WA_XFER_ABORT;
 506	b->cmd.wRPipe = rpipe->descr.wRPipeIndex;
 507	b->cmd.dwTransferID = wa_xfer_id_le32(xfer);
 508	b->wa = wa_get(xfer->wa);
 509
 510	usb_init_urb(&b->urb);
 511	usb_fill_bulk_urb(&b->urb, xfer->wa->usb_dev,
 512		usb_sndbulkpipe(xfer->wa->usb_dev,
 513				xfer->wa->dto_epd->bEndpointAddress),
 514		&b->cmd, sizeof(b->cmd), __wa_xfer_abort_cb, b);
 515	result = usb_submit_urb(&b->urb, GFP_ATOMIC);
 516	if (result < 0)
 517		goto error_submit;
 518	return result;				/* callback frees! */
 519
 520
 521error_submit:
 522	wa_put(xfer->wa);
 523	if (printk_ratelimit())
 524		dev_err(dev, "xfer %p: Can't submit abort request: %d\n",
 525			xfer, result);
 526	kfree(b);
 527error_kmalloc:
 528	return result;
 529
 530}
 531
 532/*
 533 * Calculate the number of isoc frames starting from isoc_frame_offset
 534 * that will fit a in transfer segment.
 535 */
 536static int __wa_seg_calculate_isoc_frame_count(struct wa_xfer *xfer,
 537	int isoc_frame_offset, int *total_size)
 538{
 539	int segment_size = 0, frame_count = 0;
 540	int index = isoc_frame_offset;
 541	struct usb_iso_packet_descriptor *iso_frame_desc =
 542		xfer->urb->iso_frame_desc;
 543
 544	while ((index < xfer->urb->number_of_packets)
 545		&& ((segment_size + iso_frame_desc[index].length)
 546				<= xfer->seg_size)) {
 547		/*
 548		 * For Alereon HWA devices, only include an isoc frame in an
 549		 * out segment if it is physically contiguous with the previous
 550		 * frame.  This is required because those devices expect
 551		 * the isoc frames to be sent as a single USB transaction as
 552		 * opposed to one transaction per frame with standard HWA.
 553		 */
 554		if ((xfer->wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC)
 555			&& (xfer->is_inbound == 0)
 556			&& (index > isoc_frame_offset)
 557			&& ((iso_frame_desc[index - 1].offset +
 558				iso_frame_desc[index - 1].length) !=
 559				iso_frame_desc[index].offset))
 560			break;
 561
 562		/* this frame fits. count it. */
 563		++frame_count;
 564		segment_size += iso_frame_desc[index].length;
 565
 566		/* move to the next isoc frame. */
 567		++index;
 568	}
 569
 570	*total_size = segment_size;
 571	return frame_count;
 572}
 573
 574/*
 575 *
 576 * @returns < 0 on error, transfer segment request size if ok
 577 */
 578static ssize_t __wa_xfer_setup_sizes(struct wa_xfer *xfer,
 579				     enum wa_xfer_type *pxfer_type)
 580{
 581	ssize_t result;
 582	struct device *dev = &xfer->wa->usb_iface->dev;
 583	size_t maxpktsize;
 584	struct urb *urb = xfer->urb;
 585	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 586
 587	switch (rpipe->descr.bmAttribute & 0x3) {
 588	case USB_ENDPOINT_XFER_CONTROL:
 589		*pxfer_type = WA_XFER_TYPE_CTL;
 590		result = sizeof(struct wa_xfer_ctl);
 591		break;
 592	case USB_ENDPOINT_XFER_INT:
 593	case USB_ENDPOINT_XFER_BULK:
 594		*pxfer_type = WA_XFER_TYPE_BI;
 595		result = sizeof(struct wa_xfer_bi);
 596		break;
 597	case USB_ENDPOINT_XFER_ISOC:
 598		*pxfer_type = WA_XFER_TYPE_ISO;
 599		result = sizeof(struct wa_xfer_hwaiso);
 600		break;
 601	default:
 602		/* never happens */
 603		BUG();
 604		result = -EINVAL;	/* shut gcc up */
 605	}
 606	xfer->is_inbound = urb->pipe & USB_DIR_IN ? 1 : 0;
 607	xfer->is_dma = urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP ? 1 : 0;
 608
 609	maxpktsize = le16_to_cpu(rpipe->descr.wMaxPacketSize);
 610	xfer->seg_size = le16_to_cpu(rpipe->descr.wBlocks)
 611		* 1 << (xfer->wa->wa_descr->bRPipeBlockSize - 1);
 612	/* Compute the segment size and make sure it is a multiple of
 613	 * the maxpktsize (WUSB1.0[8.3.3.1])...not really too much of
 614	 * a check (FIXME) */
 615	if (xfer->seg_size < maxpktsize) {
 616		dev_err(dev,
 617			"HW BUG? seg_size %zu smaller than maxpktsize %zu\n",
 618			xfer->seg_size, maxpktsize);
 619		result = -EINVAL;
 620		goto error;
 621	}
 622	xfer->seg_size = (xfer->seg_size / maxpktsize) * maxpktsize;
 623	if ((rpipe->descr.bmAttribute & 0x3) == USB_ENDPOINT_XFER_ISOC) {
 624		int index = 0;
 625
 626		xfer->segs = 0;
 627		/*
 628		 * loop over urb->number_of_packets to determine how many
 629		 * xfer segments will be needed to send the isoc frames.
 630		 */
 631		while (index < urb->number_of_packets) {
 632			int seg_size; /* don't care. */
 633			index += __wa_seg_calculate_isoc_frame_count(xfer,
 634					index, &seg_size);
 635			++xfer->segs;
 636		}
 637	} else {
 638		xfer->segs = DIV_ROUND_UP(urb->transfer_buffer_length,
 639						xfer->seg_size);
 640		if (xfer->segs == 0 && *pxfer_type == WA_XFER_TYPE_CTL)
 641			xfer->segs = 1;
 642	}
 643
 644	if (xfer->segs > WA_SEGS_MAX) {
 645		dev_err(dev, "BUG? oops, number of segments %zu bigger than %d\n",
 646			(urb->transfer_buffer_length/xfer->seg_size),
 647			WA_SEGS_MAX);
 648		result = -EINVAL;
 649		goto error;
 650	}
 651error:
 652	return result;
 653}
 654
 655static void __wa_setup_isoc_packet_descr(
 656		struct wa_xfer_packet_info_hwaiso *packet_desc,
 657		struct wa_xfer *xfer,
 658		struct wa_seg *seg) {
 659	struct usb_iso_packet_descriptor *iso_frame_desc =
 660		xfer->urb->iso_frame_desc;
 661	int frame_index;
 662
 663	/* populate isoc packet descriptor. */
 664	packet_desc->bPacketType = WA_XFER_ISO_PACKET_INFO;
 665	packet_desc->wLength = cpu_to_le16(sizeof(*packet_desc) +
 666		(sizeof(packet_desc->PacketLength[0]) *
 667			seg->isoc_frame_count));
 668	for (frame_index = 0; frame_index < seg->isoc_frame_count;
 669		++frame_index) {
 670		int offset_index = frame_index + seg->isoc_frame_offset;
 671		packet_desc->PacketLength[frame_index] =
 672			cpu_to_le16(iso_frame_desc[offset_index].length);
 673	}
 674}
 675
 676
 677/* Fill in the common request header and xfer-type specific data. */
 678static void __wa_xfer_setup_hdr0(struct wa_xfer *xfer,
 679				 struct wa_xfer_hdr *xfer_hdr0,
 680				 enum wa_xfer_type xfer_type,
 681				 size_t xfer_hdr_size)
 682{
 683	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
 684	struct wa_seg *seg = xfer->seg[0];
 685
 686	xfer_hdr0 = &seg->xfer_hdr;
 687	xfer_hdr0->bLength = xfer_hdr_size;
 688	xfer_hdr0->bRequestType = xfer_type;
 689	xfer_hdr0->wRPipe = rpipe->descr.wRPipeIndex;
 690	xfer_hdr0->dwTransferID = wa_xfer_id_le32(xfer);
 691	xfer_hdr0->bTransferSegment = 0;
 692	switch (xfer_type) {
 693	case WA_XFER_TYPE_CTL: {
 694		struct wa_xfer_ctl *xfer_ctl =
 695			container_of(xfer_hdr0, struct wa_xfer_ctl, hdr);
 696		xfer_ctl->bmAttribute = xfer->is_inbound ? 1 : 0;
 697		memcpy(&xfer_ctl->baSetupData, xfer->urb->setup_packet,
 698		       sizeof(xfer_ctl->baSetupData));
 699		break;
 700	}
 701	case WA_XFER_TYPE_BI:
 702		break;
 703	case WA_XFER_TYPE_ISO: {
 704		struct wa_xfer_hwaiso *xfer_iso =
 705			container_of(xfer_hdr0, struct wa_xfer_hwaiso, hdr);
 706		struct wa_xfer_packet_info_hwaiso *packet_desc =
 707			((void *)xfer_iso) + xfer_hdr_size;
 708
 709		/* populate the isoc section of the transfer request. */
 710		xfer_iso->dwNumOfPackets = cpu_to_le32(seg->isoc_frame_count);
 711		/* populate isoc packet descriptor. */
 712		__wa_setup_isoc_packet_descr(packet_desc, xfer, seg);
 713		break;
 714	}
 715	default:
 716		BUG();
 717	};
 718}
 719
 720/*
 721 * Callback for the OUT data phase of the segment request
 722 *
 723 * Check wa_seg_tr_cb(); most comments also apply here because this
 724 * function does almost the same thing and they work closely
 725 * together.
 726 *
 727 * If the seg request has failed but this DTO phase has succeeded,
 728 * wa_seg_tr_cb() has already failed the segment and moved the
 729 * status to WA_SEG_ERROR, so this will go through 'case 0' and
 730 * effectively do nothing.
 731 */
 732static void wa_seg_dto_cb(struct urb *urb)
 733{
 734	struct wa_seg *seg = urb->context;
 735	struct wa_xfer *xfer = seg->xfer;
 736	struct wahc *wa;
 737	struct device *dev;
 738	struct wa_rpipe *rpipe;
 739	unsigned long flags;
 740	unsigned rpipe_ready = 0;
 741	int data_send_done = 1, release_dto = 0, holding_dto = 0;
 742	u8 done = 0;
 743	int result;
 744
 745	/* free the sg if it was used. */
 746	kfree(urb->sg);
 747	urb->sg = NULL;
 748
 749	spin_lock_irqsave(&xfer->lock, flags);
 750	wa = xfer->wa;
 751	dev = &wa->usb_iface->dev;
 752	if (usb_pipeisoc(xfer->urb->pipe)) {
 753		/* Alereon HWA sends all isoc frames in a single transfer. */
 754		if (wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC)
 755			seg->isoc_frame_index += seg->isoc_frame_count;
 756		else
 757			seg->isoc_frame_index += 1;
 758		if (seg->isoc_frame_index < seg->isoc_frame_count) {
 759			data_send_done = 0;
 760			holding_dto = 1; /* checked in error cases. */
 761			/*
 762			 * if this is the last isoc frame of the segment, we
 763			 * can release DTO after sending this frame.
 764			 */
 765			if ((seg->isoc_frame_index + 1) >=
 766				seg->isoc_frame_count)
 767				release_dto = 1;
 768		}
 769		dev_dbg(dev, "xfer 0x%08X#%u: isoc frame = %d, holding_dto = %d, release_dto = %d.\n",
 770			wa_xfer_id(xfer), seg->index, seg->isoc_frame_index,
 771			holding_dto, release_dto);
 772	}
 773	spin_unlock_irqrestore(&xfer->lock, flags);
 774
 775	switch (urb->status) {
 776	case 0:
 777		spin_lock_irqsave(&xfer->lock, flags);
 778		seg->result += urb->actual_length;
 779		if (data_send_done) {
 780			dev_dbg(dev, "xfer 0x%08X#%u: data out done (%zu bytes)\n",
 781				wa_xfer_id(xfer), seg->index, seg->result);
 782			if (seg->status < WA_SEG_PENDING)
 783				seg->status = WA_SEG_PENDING;
 784		} else {
 785			/* should only hit this for isoc xfers. */
 786			/*
 787			 * Populate the dto URB with the next isoc frame buffer,
 788			 * send the URB and release DTO if we no longer need it.
 789			 */
 790			 __wa_populate_dto_urb_isoc(xfer, seg,
 791				seg->isoc_frame_offset + seg->isoc_frame_index);
 792
 793			/* resubmit the URB with the next isoc frame. */
 794			/* take a ref on resubmit. */
 795			wa_xfer_get(xfer);
 796			result = usb_submit_urb(seg->dto_urb, GFP_ATOMIC);
 797			if (result < 0) {
 798				dev_err(dev, "xfer 0x%08X#%u: DTO submit failed: %d\n",
 799				       wa_xfer_id(xfer), seg->index, result);
 800				spin_unlock_irqrestore(&xfer->lock, flags);
 801				goto error_dto_submit;
 802			}
 803		}
 804		spin_unlock_irqrestore(&xfer->lock, flags);
 805		if (release_dto) {
 806			__wa_dto_put(wa);
 807			wa_check_for_delayed_rpipes(wa);
 808		}
 809		break;
 810	case -ECONNRESET:	/* URB unlinked; no need to do anything */
 811	case -ENOENT:		/* as it was done by the who unlinked us */
 812		if (holding_dto) {
 813			__wa_dto_put(wa);
 814			wa_check_for_delayed_rpipes(wa);
 815		}
 816		break;
 817	default:		/* Other errors ... */
 818		dev_err(dev, "xfer 0x%08X#%u: data out error %d\n",
 819			wa_xfer_id(xfer), seg->index, urb->status);
 820		goto error_default;
 821	}
 822
 823	/* taken when this URB was submitted. */
 824	wa_xfer_put(xfer);
 825	return;
 826
 827error_dto_submit:
 828	/* taken on resubmit attempt. */
 829	wa_xfer_put(xfer);
 830error_default:
 831	spin_lock_irqsave(&xfer->lock, flags);
 832	rpipe = xfer->ep->hcpriv;
 833	if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
 834		    EDC_ERROR_TIMEFRAME)){
 835		dev_err(dev, "DTO: URB max acceptable errors exceeded, resetting device\n");
 836		wa_reset_all(wa);
 837	}
 838	if (seg->status != WA_SEG_ERROR) {
 839		seg->result = urb->status;
 840		__wa_xfer_abort(xfer);
 841		rpipe_ready = rpipe_avail_inc(rpipe);
 842		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_ERROR);
 843	}
 844	spin_unlock_irqrestore(&xfer->lock, flags);
 845	if (holding_dto) {
 846		__wa_dto_put(wa);
 847		wa_check_for_delayed_rpipes(wa);
 848	}
 849	if (done)
 850		wa_xfer_completion(xfer);
 851	if (rpipe_ready)
 852		wa_xfer_delayed_run(rpipe);
 853	/* taken when this URB was submitted. */
 854	wa_xfer_put(xfer);
 855}
 856
 857/*
 858 * Callback for the isoc packet descriptor phase of the segment request
 859 *
 860 * Check wa_seg_tr_cb(); most comments also apply here because this
 861 * function does almost the same thing and they work closely
 862 * together.
 863 *
 864 * If the seg request has failed but this phase has succeeded,
 865 * wa_seg_tr_cb() has already failed the segment and moved the
 866 * status to WA_SEG_ERROR, so this will go through 'case 0' and
 867 * effectively do nothing.
 868 */
 869static void wa_seg_iso_pack_desc_cb(struct urb *urb)
 870{
 871	struct wa_seg *seg = urb->context;
 872	struct wa_xfer *xfer = seg->xfer;
 873	struct wahc *wa;
 874	struct device *dev;
 875	struct wa_rpipe *rpipe;
 876	unsigned long flags;
 877	unsigned rpipe_ready = 0;
 878	u8 done = 0;
 879
 880	switch (urb->status) {
 881	case 0:
 882		spin_lock_irqsave(&xfer->lock, flags);
 883		wa = xfer->wa;
 884		dev = &wa->usb_iface->dev;
 885		dev_dbg(dev, "iso xfer %08X#%u: packet descriptor done\n",
 886			wa_xfer_id(xfer), seg->index);
 887		if (xfer->is_inbound && seg->status < WA_SEG_PENDING)
 888			seg->status = WA_SEG_PENDING;
 889		spin_unlock_irqrestore(&xfer->lock, flags);
 890		break;
 891	case -ECONNRESET:	/* URB unlinked; no need to do anything */
 892	case -ENOENT:		/* as it was done by the who unlinked us */
 893		break;
 894	default:		/* Other errors ... */
 895		spin_lock_irqsave(&xfer->lock, flags);
 896		wa = xfer->wa;
 897		dev = &wa->usb_iface->dev;
 898		rpipe = xfer->ep->hcpriv;
 899		pr_err_ratelimited("iso xfer %08X#%u: packet descriptor error %d\n",
 900				wa_xfer_id(xfer), seg->index, urb->status);
 901		if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
 902			    EDC_ERROR_TIMEFRAME)){
 903			dev_err(dev, "iso xfer: URB max acceptable errors exceeded, resetting device\n");
 904			wa_reset_all(wa);
 905		}
 906		if (seg->status != WA_SEG_ERROR) {
 907			usb_unlink_urb(seg->dto_urb);
 908			seg->result = urb->status;
 909			__wa_xfer_abort(xfer);
 910			rpipe_ready = rpipe_avail_inc(rpipe);
 911			done = __wa_xfer_mark_seg_as_done(xfer, seg,
 912					WA_SEG_ERROR);
 913		}
 914		spin_unlock_irqrestore(&xfer->lock, flags);
 915		if (done)
 916			wa_xfer_completion(xfer);
 917		if (rpipe_ready)
 918			wa_xfer_delayed_run(rpipe);
 919	}
 920	/* taken when this URB was submitted. */
 921	wa_xfer_put(xfer);
 922}
 923
 924/*
 925 * Callback for the segment request
 926 *
 927 * If successful transition state (unless already transitioned or
 928 * outbound transfer); otherwise, take a note of the error, mark this
 929 * segment done and try completion.
 930 *
 931 * Note we don't access until we are sure that the transfer hasn't
 932 * been cancelled (ECONNRESET, ENOENT), which could mean that
 933 * seg->xfer could be already gone.
 934 *
 935 * We have to check before setting the status to WA_SEG_PENDING
 936 * because sometimes the xfer result callback arrives before this
 937 * callback (geeeeeeze), so it might happen that we are already in
 938 * another state. As well, we don't set it if the transfer is not inbound,
 939 * as in that case, wa_seg_dto_cb will do it when the OUT data phase
 940 * finishes.
 941 */
 942static void wa_seg_tr_cb(struct urb *urb)
 943{
 944	struct wa_seg *seg = urb->context;
 945	struct wa_xfer *xfer = seg->xfer;
 946	struct wahc *wa;
 947	struct device *dev;
 948	struct wa_rpipe *rpipe;
 949	unsigned long flags;
 950	unsigned rpipe_ready;
 951	u8 done = 0;
 952
 953	switch (urb->status) {
 954	case 0:
 955		spin_lock_irqsave(&xfer->lock, flags);
 956		wa = xfer->wa;
 957		dev = &wa->usb_iface->dev;
 958		dev_dbg(dev, "xfer %p ID 0x%08X#%u: request done\n",
 959			xfer, wa_xfer_id(xfer), seg->index);
 960		if (xfer->is_inbound &&
 961			seg->status < WA_SEG_PENDING &&
 962			!(usb_pipeisoc(xfer->urb->pipe)))
 963			seg->status = WA_SEG_PENDING;
 964		spin_unlock_irqrestore(&xfer->lock, flags);
 965		break;
 966	case -ECONNRESET:	/* URB unlinked; no need to do anything */
 967	case -ENOENT:		/* as it was done by the who unlinked us */
 968		break;
 969	default:		/* Other errors ... */
 970		spin_lock_irqsave(&xfer->lock, flags);
 971		wa = xfer->wa;
 972		dev = &wa->usb_iface->dev;
 973		rpipe = xfer->ep->hcpriv;
 974		if (printk_ratelimit())
 975			dev_err(dev, "xfer %p ID 0x%08X#%u: request error %d\n",
 976				xfer, wa_xfer_id(xfer), seg->index,
 977				urb->status);
 978		if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
 979			    EDC_ERROR_TIMEFRAME)){
 980			dev_err(dev, "DTO: URB max acceptable errors "
 981				"exceeded, resetting device\n");
 982			wa_reset_all(wa);
 983		}
 984		usb_unlink_urb(seg->isoc_pack_desc_urb);
 985		usb_unlink_urb(seg->dto_urb);
 986		seg->result = urb->status;
 987		__wa_xfer_abort(xfer);
 988		rpipe_ready = rpipe_avail_inc(rpipe);
 989		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_ERROR);
 990		spin_unlock_irqrestore(&xfer->lock, flags);
 991		if (done)
 992			wa_xfer_completion(xfer);
 993		if (rpipe_ready)
 994			wa_xfer_delayed_run(rpipe);
 995	}
 996	/* taken when this URB was submitted. */
 997	wa_xfer_put(xfer);
 998}
 999
1000/*
1001 * Allocate an SG list to store bytes_to_transfer bytes and copy the
1002 * subset of the in_sg that matches the buffer subset
1003 * we are about to transfer.
1004 */
1005static struct scatterlist *wa_xfer_create_subset_sg(struct scatterlist *in_sg,
1006	const unsigned int bytes_transferred,
1007	const unsigned int bytes_to_transfer, int *out_num_sgs)
1008{
1009	struct scatterlist *out_sg;
1010	unsigned int bytes_processed = 0, offset_into_current_page_data = 0,
1011		nents;
1012	struct scatterlist *current_xfer_sg = in_sg;
1013	struct scatterlist *current_seg_sg, *last_seg_sg;
1014
1015	/* skip previously transferred pages. */
1016	while ((current_xfer_sg) &&
1017			(bytes_processed < bytes_transferred)) {
1018		bytes_processed += current_xfer_sg->length;
1019
1020		/* advance the sg if current segment starts on or past the
1021			next page. */
1022		if (bytes_processed <= bytes_transferred)
1023			current_xfer_sg = sg_next(current_xfer_sg);
1024	}
1025
1026	/* the data for the current segment starts in current_xfer_sg.
1027		calculate the offset. */
1028	if (bytes_processed > bytes_transferred) {
1029		offset_into_current_page_data = current_xfer_sg->length -
1030			(bytes_processed - bytes_transferred);
1031	}
1032
1033	/* calculate the number of pages needed by this segment. */
1034	nents = DIV_ROUND_UP((bytes_to_transfer +
1035		offset_into_current_page_data +
1036		current_xfer_sg->offset),
1037		PAGE_SIZE);
1038
1039	out_sg = kmalloc((sizeof(struct scatterlist) * nents), GFP_ATOMIC);
1040	if (out_sg) {
1041		sg_init_table(out_sg, nents);
1042
1043		/* copy the portion of the incoming SG that correlates to the
1044		 * data to be transferred by this segment to the segment SG. */
1045		last_seg_sg = current_seg_sg = out_sg;
1046		bytes_processed = 0;
1047
1048		/* reset nents and calculate the actual number of sg entries
1049			needed. */
1050		nents = 0;
1051		while ((bytes_processed < bytes_to_transfer) &&
1052				current_seg_sg && current_xfer_sg) {
1053			unsigned int page_len = min((current_xfer_sg->length -
1054				offset_into_current_page_data),
1055				(bytes_to_transfer - bytes_processed));
1056
1057			sg_set_page(current_seg_sg, sg_page(current_xfer_sg),
1058				page_len,
1059				current_xfer_sg->offset +
1060				offset_into_current_page_data);
1061
1062			bytes_processed += page_len;
1063
1064			last_seg_sg = current_seg_sg;
1065			current_seg_sg = sg_next(current_seg_sg);
1066			current_xfer_sg = sg_next(current_xfer_sg);
1067
1068			/* only the first page may require additional offset. */
1069			offset_into_current_page_data = 0;
1070			nents++;
1071		}
1072
1073		/* update num_sgs and terminate the list since we may have
1074		 *  concatenated pages. */
1075		sg_mark_end(last_seg_sg);
1076		*out_num_sgs = nents;
1077	}
1078
1079	return out_sg;
1080}
1081
1082/*
1083 * Populate DMA buffer info for the isoc dto urb.
1084 */
1085static void __wa_populate_dto_urb_isoc(struct wa_xfer *xfer,
1086	struct wa_seg *seg, int curr_iso_frame)
1087{
1088	seg->dto_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1089	seg->dto_urb->sg = NULL;
1090	seg->dto_urb->num_sgs = 0;
1091	/* dto urb buffer address pulled from iso_frame_desc. */
1092	seg->dto_urb->transfer_dma = xfer->urb->transfer_dma +
1093		xfer->urb->iso_frame_desc[curr_iso_frame].offset;
1094	/* The Alereon HWA sends a single URB with all isoc segs. */
1095	if (xfer->wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC)
1096		seg->dto_urb->transfer_buffer_length = seg->isoc_size;
1097	else
1098		seg->dto_urb->transfer_buffer_length =
1099			xfer->urb->iso_frame_desc[curr_iso_frame].length;
1100}
1101
1102/*
1103 * Populate buffer ptr and size, DMA buffer or SG list for the dto urb.
1104 */
1105static int __wa_populate_dto_urb(struct wa_xfer *xfer,
1106	struct wa_seg *seg, size_t buf_itr_offset, size_t buf_itr_size)
1107{
1108	int result = 0;
1109
1110	if (xfer->is_dma) {
1111		seg->dto_urb->transfer_dma =
1112			xfer->urb->transfer_dma + buf_itr_offset;
1113		seg->dto_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1114		seg->dto_urb->sg = NULL;
1115		seg->dto_urb->num_sgs = 0;
1116	} else {
1117		/* do buffer or SG processing. */
1118		seg->dto_urb->transfer_flags &=
1119			~URB_NO_TRANSFER_DMA_MAP;
1120		/* this should always be 0 before a resubmit. */
1121		seg->dto_urb->num_mapped_sgs = 0;
1122
1123		if (xfer->urb->transfer_buffer) {
1124			seg->dto_urb->transfer_buffer =
1125				xfer->urb->transfer_buffer +
1126				buf_itr_offset;
1127			seg->dto_urb->sg = NULL;
1128			seg->dto_urb->num_sgs = 0;
1129		} else {
1130			seg->dto_urb->transfer_buffer = NULL;
1131
1132			/*
1133			 * allocate an SG list to store seg_size bytes
1134			 * and copy the subset of the xfer->urb->sg that
1135			 * matches the buffer subset we are about to
1136			 * read.
1137			 */
1138			seg->dto_urb->sg = wa_xfer_create_subset_sg(
1139				xfer->urb->sg,
1140				buf_itr_offset, buf_itr_size,
1141				&(seg->dto_urb->num_sgs));
1142			if (!(seg->dto_urb->sg))
1143				result = -ENOMEM;
1144		}
1145	}
1146	seg->dto_urb->transfer_buffer_length = buf_itr_size;
1147
1148	return result;
1149}
1150
1151/*
1152 * Allocate the segs array and initialize each of them
1153 *
1154 * The segments are freed by wa_xfer_destroy() when the xfer use count
1155 * drops to zero; however, because each segment is given the same life
1156 * cycle as the USB URB it contains, it is actually freed by
1157 * usb_put_urb() on the contained USB URB (twisted, eh?).
1158 */
1159static int __wa_xfer_setup_segs(struct wa_xfer *xfer, size_t xfer_hdr_size)
1160{
1161	int result, cnt, isoc_frame_offset = 0;
1162	size_t alloc_size = sizeof(*xfer->seg[0])
1163		- sizeof(xfer->seg[0]->xfer_hdr) + xfer_hdr_size;
1164	struct usb_device *usb_dev = xfer->wa->usb_dev;
1165	const struct usb_endpoint_descriptor *dto_epd = xfer->wa->dto_epd;
1166	struct wa_seg *seg;
1167	size_t buf_itr, buf_size, buf_itr_size;
1168
1169	result = -ENOMEM;
1170	xfer->seg = kcalloc(xfer->segs, sizeof(xfer->seg[0]), GFP_ATOMIC);
1171	if (xfer->seg == NULL)
1172		goto error_segs_kzalloc;
1173	buf_itr = 0;
1174	buf_size = xfer->urb->transfer_buffer_length;
1175	for (cnt = 0; cnt < xfer->segs; cnt++) {
1176		size_t iso_pkt_descr_size = 0;
1177		int seg_isoc_frame_count = 0, seg_isoc_size = 0;
1178
1179		/*
1180		 * Adjust the size of the segment object to contain space for
1181		 * the isoc packet descriptor buffer.
1182		 */
1183		if (usb_pipeisoc(xfer->urb->pipe)) {
1184			seg_isoc_frame_count =
1185				__wa_seg_calculate_isoc_frame_count(xfer,
1186					isoc_frame_offset, &seg_isoc_size);
1187
1188			iso_pkt_descr_size =
1189				sizeof(struct wa_xfer_packet_info_hwaiso) +
1190				(seg_isoc_frame_count * sizeof(__le16));
1191		}
1192		result = -ENOMEM;
1193		seg = xfer->seg[cnt] = kmalloc(alloc_size + iso_pkt_descr_size,
1194						GFP_ATOMIC);
1195		if (seg == NULL)
1196			goto error_seg_kmalloc;
1197		wa_seg_init(seg);
1198		seg->xfer = xfer;
1199		seg->index = cnt;
1200		usb_fill_bulk_urb(&seg->tr_urb, usb_dev,
1201				  usb_sndbulkpipe(usb_dev,
1202						  dto_epd->bEndpointAddress),
1203				  &seg->xfer_hdr, xfer_hdr_size,
1204				  wa_seg_tr_cb, seg);
1205		buf_itr_size = min(buf_size, xfer->seg_size);
1206
1207		if (usb_pipeisoc(xfer->urb->pipe)) {
1208			seg->isoc_frame_count = seg_isoc_frame_count;
1209			seg->isoc_frame_offset = isoc_frame_offset;
1210			seg->isoc_size = seg_isoc_size;
1211			/* iso packet descriptor. */
1212			seg->isoc_pack_desc_urb =
1213					usb_alloc_urb(0, GFP_ATOMIC);
1214			if (seg->isoc_pack_desc_urb == NULL)
1215				goto error_iso_pack_desc_alloc;
1216			/*
1217			 * The buffer for the isoc packet descriptor starts
1218			 * after the transfer request header in the
1219			 * segment object memory buffer.
1220			 */
1221			usb_fill_bulk_urb(
1222				seg->isoc_pack_desc_urb, usb_dev,
1223				usb_sndbulkpipe(usb_dev,
1224					dto_epd->bEndpointAddress),
1225				(void *)(&seg->xfer_hdr) +
1226					xfer_hdr_size,
1227				iso_pkt_descr_size,
1228				wa_seg_iso_pack_desc_cb, seg);
1229
1230			/* adjust starting frame offset for next seg. */
1231			isoc_frame_offset += seg_isoc_frame_count;
1232		}
1233
1234		if (xfer->is_inbound == 0 && buf_size > 0) {
1235			/* outbound data. */
1236			seg->dto_urb = usb_alloc_urb(0, GFP_ATOMIC);
1237			if (seg->dto_urb == NULL)
1238				goto error_dto_alloc;
1239			usb_fill_bulk_urb(
1240				seg->dto_urb, usb_dev,
1241				usb_sndbulkpipe(usb_dev,
1242						dto_epd->bEndpointAddress),
1243				NULL, 0, wa_seg_dto_cb, seg);
1244
1245			if (usb_pipeisoc(xfer->urb->pipe)) {
1246				/*
1247				 * Fill in the xfer buffer information for the
1248				 * first isoc frame.  Subsequent frames in this
1249				 * segment will be filled in and sent from the
1250				 * DTO completion routine, if needed.
1251				 */
1252				__wa_populate_dto_urb_isoc(xfer, seg,
1253					seg->isoc_frame_offset);
1254			} else {
1255				/* fill in the xfer buffer information. */
1256				result = __wa_populate_dto_urb(xfer, seg,
1257							buf_itr, buf_itr_size);
1258				if (result < 0)
1259					goto error_seg_outbound_populate;
1260
1261				buf_itr += buf_itr_size;
1262				buf_size -= buf_itr_size;
1263			}
1264		}
1265		seg->status = WA_SEG_READY;
1266	}
1267	return 0;
1268
1269	/*
1270	 * Free the memory for the current segment which failed to init.
1271	 * Use the fact that cnt is left at were it failed.  The remaining
1272	 * segments will be cleaned up by wa_xfer_destroy.
1273	 */
1274error_seg_outbound_populate:
1275	usb_free_urb(xfer->seg[cnt]->dto_urb);
1276error_dto_alloc:
1277	usb_free_urb(xfer->seg[cnt]->isoc_pack_desc_urb);
1278error_iso_pack_desc_alloc:
1279	kfree(xfer->seg[cnt]);
1280	xfer->seg[cnt] = NULL;
1281error_seg_kmalloc:
1282error_segs_kzalloc:
1283	return result;
1284}
1285
1286/*
1287 * Allocates all the stuff needed to submit a transfer
1288 *
1289 * Breaks the whole data buffer in a list of segments, each one has a
1290 * structure allocated to it and linked in xfer->seg[index]
1291 *
1292 * FIXME: merge setup_segs() and the last part of this function, no
1293 *        need to do two for loops when we could run everything in a
1294 *        single one
1295 */
1296static int __wa_xfer_setup(struct wa_xfer *xfer, struct urb *urb)
1297{
1298	int result;
1299	struct device *dev = &xfer->wa->usb_iface->dev;
1300	enum wa_xfer_type xfer_type = 0; /* shut up GCC */
1301	size_t xfer_hdr_size, cnt, transfer_size;
1302	struct wa_xfer_hdr *xfer_hdr0, *xfer_hdr;
1303
1304	result = __wa_xfer_setup_sizes(xfer, &xfer_type);
1305	if (result < 0)
1306		goto error_setup_sizes;
1307	xfer_hdr_size = result;
1308	result = __wa_xfer_setup_segs(xfer, xfer_hdr_size);
1309	if (result < 0) {
1310		dev_err(dev, "xfer %p: Failed to allocate %d segments: %d\n",
1311			xfer, xfer->segs, result);
1312		goto error_setup_segs;
1313	}
1314	/* Fill the first header */
1315	xfer_hdr0 = &xfer->seg[0]->xfer_hdr;
1316	wa_xfer_id_init(xfer);
1317	__wa_xfer_setup_hdr0(xfer, xfer_hdr0, xfer_type, xfer_hdr_size);
1318
1319	/* Fill remaining headers */
1320	xfer_hdr = xfer_hdr0;
1321	if (xfer_type == WA_XFER_TYPE_ISO) {
1322		xfer_hdr0->dwTransferLength =
1323			cpu_to_le32(xfer->seg[0]->isoc_size);
1324		for (cnt = 1; cnt < xfer->segs; cnt++) {
1325			struct wa_xfer_packet_info_hwaiso *packet_desc;
1326			struct wa_seg *seg = xfer->seg[cnt];
1327			struct wa_xfer_hwaiso *xfer_iso;
1328
1329			xfer_hdr = &seg->xfer_hdr;
1330			xfer_iso = container_of(xfer_hdr,
1331						struct wa_xfer_hwaiso, hdr);
1332			packet_desc = ((void *)xfer_hdr) + xfer_hdr_size;
1333			/*
1334			 * Copy values from the 0th header. Segment specific
1335			 * values are set below.
1336			 */
1337			memcpy(xfer_hdr, xfer_hdr0, xfer_hdr_size);
1338			xfer_hdr->bTransferSegment = cnt;
1339			xfer_hdr->dwTransferLength =
1340				cpu_to_le32(seg->isoc_size);
1341			xfer_iso->dwNumOfPackets =
1342					cpu_to_le32(seg->isoc_frame_count);
1343			__wa_setup_isoc_packet_descr(packet_desc, xfer, seg);
1344			seg->status = WA_SEG_READY;
1345		}
1346	} else {
1347		transfer_size = urb->transfer_buffer_length;
1348		xfer_hdr0->dwTransferLength = transfer_size > xfer->seg_size ?
1349			cpu_to_le32(xfer->seg_size) :
1350			cpu_to_le32(transfer_size);
1351		transfer_size -=  xfer->seg_size;
1352		for (cnt = 1; cnt < xfer->segs; cnt++) {
1353			xfer_hdr = &xfer->seg[cnt]->xfer_hdr;
1354			memcpy(xfer_hdr, xfer_hdr0, xfer_hdr_size);
1355			xfer_hdr->bTransferSegment = cnt;
1356			xfer_hdr->dwTransferLength =
1357				transfer_size > xfer->seg_size ?
1358					cpu_to_le32(xfer->seg_size)
1359					: cpu_to_le32(transfer_size);
1360			xfer->seg[cnt]->status = WA_SEG_READY;
1361			transfer_size -=  xfer->seg_size;
1362		}
1363	}
1364	xfer_hdr->bTransferSegment |= 0x80;	/* this is the last segment */
1365	result = 0;
1366error_setup_segs:
1367error_setup_sizes:
1368	return result;
1369}
1370
1371/*
1372 *
1373 *
1374 * rpipe->seg_lock is held!
1375 */
1376static int __wa_seg_submit(struct wa_rpipe *rpipe, struct wa_xfer *xfer,
1377			   struct wa_seg *seg, int *dto_done)
1378{
1379	int result;
1380
1381	/* default to done unless we encounter a multi-frame isoc segment. */
1382	*dto_done = 1;
1383
1384	/*
1385	 * Take a ref for each segment urb so the xfer cannot disappear until
1386	 * all of the callbacks run.
1387	 */
1388	wa_xfer_get(xfer);
1389	/* submit the transfer request. */
1390	seg->status = WA_SEG_SUBMITTED;
1391	result = usb_submit_urb(&seg->tr_urb, GFP_ATOMIC);
1392	if (result < 0) {
1393		pr_err("%s: xfer %p#%u: REQ submit failed: %d\n",
1394		       __func__, xfer, seg->index, result);
1395		wa_xfer_put(xfer);
1396		goto error_tr_submit;
1397	}
1398	/* submit the isoc packet descriptor if present. */
1399	if (seg->isoc_pack_desc_urb) {
1400		wa_xfer_get(xfer);
1401		result = usb_submit_urb(seg->isoc_pack_desc_urb, GFP_ATOMIC);
1402		seg->isoc_frame_index = 0;
1403		if (result < 0) {
1404			pr_err("%s: xfer %p#%u: ISO packet descriptor submit failed: %d\n",
1405			       __func__, xfer, seg->index, result);
1406			wa_xfer_put(xfer);
1407			goto error_iso_pack_desc_submit;
1408		}
1409	}
1410	/* submit the out data if this is an out request. */
1411	if (seg->dto_urb) {
1412		struct wahc *wa = xfer->wa;
1413		wa_xfer_get(xfer);
1414		result = usb_submit_urb(seg->dto_urb, GFP_ATOMIC);
1415		if (result < 0) {
1416			pr_err("%s: xfer %p#%u: DTO submit failed: %d\n",
1417			       __func__, xfer, seg->index, result);
1418			wa_xfer_put(xfer);
1419			goto error_dto_submit;
1420		}
1421		/*
1422		 * If this segment contains more than one isoc frame, hold
1423		 * onto the dto resource until we send all frames.
1424		 * Only applies to non-Alereon devices.
1425		 */
1426		if (((wa->quirks & WUSB_QUIRK_ALEREON_HWA_CONCAT_ISOC) == 0)
1427			&& (seg->isoc_frame_count > 1))
1428			*dto_done = 0;
1429	}
1430	rpipe_avail_dec(rpipe);
1431	return 0;
1432
1433error_dto_submit:
1434	usb_unlink_urb(seg->isoc_pack_desc_urb);
1435error_iso_pack_desc_submit:
1436	usb_unlink_urb(&seg->tr_urb);
1437error_tr_submit:
1438	seg->status = WA_SEG_ERROR;
1439	seg->result = result;
1440	*dto_done = 1;
1441	return result;
1442}
1443
1444/*
1445 * Execute more queued request segments until the maximum concurrent allowed.
1446 * Return true if the DTO resource was acquired and released.
1447 *
1448 * The ugly unlock/lock sequence on the error path is needed as the
1449 * xfer->lock normally nests the seg_lock and not viceversa.
1450 */
1451static int __wa_xfer_delayed_run(struct wa_rpipe *rpipe, int *dto_waiting)
1452{
1453	int result, dto_acquired = 0, dto_done = 0;
1454	struct device *dev = &rpipe->wa->usb_iface->dev;
1455	struct wa_seg *seg;
1456	struct wa_xfer *xfer;
1457	unsigned long flags;
1458
1459	*dto_waiting = 0;
1460
1461	spin_lock_irqsave(&rpipe->seg_lock, flags);
1462	while (atomic_read(&rpipe->segs_available) > 0
1463	      && !list_empty(&rpipe->seg_list)
1464	      && (dto_acquired = __wa_dto_try_get(rpipe->wa))) {
1465		seg = list_first_entry(&(rpipe->seg_list), struct wa_seg,
1466				 list_node);
1467		list_del(&seg->list_node);
1468		xfer = seg->xfer;
1469		/*
1470		 * Get a reference to the xfer in case the callbacks for the
1471		 * URBs submitted by __wa_seg_submit attempt to complete
1472		 * the xfer before this function completes.
1473		 */
1474		wa_xfer_get(xfer);
1475		result = __wa_seg_submit(rpipe, xfer, seg, &dto_done);
1476		/* release the dto resource if this RPIPE is done with it. */
1477		if (dto_done)
1478			__wa_dto_put(rpipe->wa);
1479		dev_dbg(dev, "xfer %p ID %08X#%u submitted from delayed [%d segments available] %d\n",
1480			xfer, wa_xfer_id(xfer), seg->index,
1481			atomic_read(&rpipe->segs_available), result);
1482		if (unlikely(result < 0)) {
1483			int done;
1484
1485			spin_unlock_irqrestore(&rpipe->seg_lock, flags);
1486			spin_lock_irqsave(&xfer->lock, flags);
1487			__wa_xfer_abort(xfer);
1488			/*
1489			 * This seg was marked as submitted when it was put on
1490			 * the RPIPE seg_list.  Mark it done.
1491			 */
1492			xfer->segs_done++;
1493			done = __wa_xfer_is_done(xfer);
1494			spin_unlock_irqrestore(&xfer->lock, flags);
1495			if (done)
1496				wa_xfer_completion(xfer);
1497			spin_lock_irqsave(&rpipe->seg_lock, flags);
1498		}
1499		wa_xfer_put(xfer);
1500	}
1501	/*
1502	 * Mark this RPIPE as waiting if dto was not acquired, there are
1503	 * delayed segs and no active transfers to wake us up later.
1504	 */
1505	if (!dto_acquired && !list_empty(&rpipe->seg_list)
1506		&& (atomic_read(&rpipe->segs_available) ==
1507			le16_to_cpu(rpipe->descr.wRequests)))
1508		*dto_waiting = 1;
1509
1510	spin_unlock_irqrestore(&rpipe->seg_lock, flags);
1511
1512	return dto_done;
1513}
1514
1515static void wa_xfer_delayed_run(struct wa_rpipe *rpipe)
1516{
1517	int dto_waiting;
1518	int dto_done = __wa_xfer_delayed_run(rpipe, &dto_waiting);
1519
1520	/*
1521	 * If this RPIPE is waiting on the DTO resource, add it to the tail of
1522	 * the waiting list.
1523	 * Otherwise, if the WA DTO resource was acquired and released by
1524	 *  __wa_xfer_delayed_run, another RPIPE may have attempted to acquire
1525	 * DTO and failed during that time.  Check the delayed list and process
1526	 * any waiters.  Start searching from the next RPIPE index.
1527	 */
1528	if (dto_waiting)
1529		wa_add_delayed_rpipe(rpipe->wa, rpipe);
1530	else if (dto_done)
1531		wa_check_for_delayed_rpipes(rpipe->wa);
1532}
1533
1534/*
1535 *
1536 * xfer->lock is taken
1537 *
1538 * On failure submitting we just stop submitting and return error;
1539 * wa_urb_enqueue_b() will execute the completion path
1540 */
1541static int __wa_xfer_submit(struct wa_xfer *xfer)
1542{
1543	int result, dto_acquired = 0, dto_done = 0, dto_waiting = 0;
1544	struct wahc *wa = xfer->wa;
1545	struct device *dev = &wa->usb_iface->dev;
1546	unsigned cnt;
1547	struct wa_seg *seg;
1548	unsigned long flags;
1549	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
1550	size_t maxrequests = le16_to_cpu(rpipe->descr.wRequests);
1551	u8 available;
1552	u8 empty;
1553
1554	spin_lock_irqsave(&wa->xfer_list_lock, flags);
1555	list_add_tail(&xfer->list_node, &wa->xfer_list);
1556	spin_unlock_irqrestore(&wa->xfer_list_lock, flags);
1557
1558	BUG_ON(atomic_read(&rpipe->segs_available) > maxrequests);
1559	result = 0;
1560	spin_lock_irqsave(&rpipe->seg_lock, flags);
1561	for (cnt = 0; cnt < xfer->segs; cnt++) {
1562		int delay_seg = 1;
1563
1564		available = atomic_read(&rpipe->segs_available);
1565		empty = list_empty(&rpipe->seg_list);
1566		seg = xfer->seg[cnt];
1567		if (available && empty) {
1568			/*
1569			 * Only attempt to acquire DTO if we have a segment
1570			 * to send.
1571			 */
1572			dto_acquired = __wa_dto_try_get(rpipe->wa);
1573			if (dto_acquired) {
1574				delay_seg = 0;
1575				result = __wa_seg_submit(rpipe, xfer, seg,
1576							&dto_done);
1577				dev_dbg(dev, "xfer %p ID 0x%08X#%u: available %u empty %u submitted\n",
1578					xfer, wa_xfer_id(xfer), cnt, available,
1579					empty);
1580				if (dto_done)
1581					__wa_dto_put(rpipe->wa);
1582
1583				if (result < 0) {
1584					__wa_xfer_abort(xfer);
1585					goto error_seg_submit;
1586				}
1587			}
1588		}
1589
1590		if (delay_seg) {
1591			dev_dbg(dev, "xfer %p ID 0x%08X#%u: available %u empty %u delayed\n",
1592				xfer, wa_xfer_id(xfer), cnt, available,  empty);
1593			seg->status = WA_SEG_DELAYED;
1594			list_add_tail(&seg->list_node, &rpipe->seg_list);
1595		}
1596		xfer->segs_submitted++;
1597	}
1598error_seg_submit:
1599	/*
1600	 * Mark this RPIPE as waiting if dto was not acquired, there are
1601	 * delayed segs and no active transfers to wake us up later.
1602	 */
1603	if (!dto_acquired && !list_empty(&rpipe->seg_list)
1604		&& (atomic_read(&rpipe->segs_available) ==
1605			le16_to_cpu(rpipe->descr.wRequests)))
1606		dto_waiting = 1;
1607	spin_unlock_irqrestore(&rpipe->seg_lock, flags);
1608
1609	if (dto_waiting)
1610		wa_add_delayed_rpipe(rpipe->wa, rpipe);
1611	else if (dto_done)
1612		wa_check_for_delayed_rpipes(rpipe->wa);
1613
1614	return result;
1615}
1616
1617/*
1618 * Second part of a URB/transfer enqueuement
1619 *
1620 * Assumes this comes from wa_urb_enqueue() [maybe through
1621 * wa_urb_enqueue_run()]. At this point:
1622 *
1623 * xfer->wa	filled and refcounted
1624 * xfer->ep	filled with rpipe refcounted if
1625 *              delayed == 0
1626 * xfer->urb 	filled and refcounted (this is the case when called
1627 *              from wa_urb_enqueue() as we come from usb_submit_urb()
1628 *              and when called by wa_urb_enqueue_run(), as we took an
1629 *              extra ref dropped by _run() after we return).
1630 * xfer->gfp	filled
1631 *
1632 * If we fail at __wa_xfer_submit(), then we just check if we are done
1633 * and if so, we run the completion procedure. However, if we are not
1634 * yet done, we do nothing and wait for the completion handlers from
1635 * the submitted URBs or from the xfer-result path to kick in. If xfer
1636 * result never kicks in, the xfer will timeout from the USB code and
1637 * dequeue() will be called.
1638 */
1639static int wa_urb_enqueue_b(struct wa_xfer *xfer)
1640{
1641	int result;
1642	unsigned long flags;
1643	struct urb *urb = xfer->urb;
1644	struct wahc *wa = xfer->wa;
1645	struct wusbhc *wusbhc = wa->wusb;
1646	struct wusb_dev *wusb_dev;
1647	unsigned done;
1648
1649	result = rpipe_get_by_ep(wa, xfer->ep, urb, xfer->gfp);
1650	if (result < 0) {
1651		pr_err("%s: error_rpipe_get\n", __func__);
1652		goto error_rpipe_get;
1653	}
1654	result = -ENODEV;
1655	/* FIXME: segmentation broken -- kills DWA */
1656	mutex_lock(&wusbhc->mutex);		/* get a WUSB dev */
1657	if (urb->dev == NULL) {
1658		mutex_unlock(&wusbhc->mutex);
1659		pr_err("%s: error usb dev gone\n", __func__);
1660		goto error_dev_gone;
1661	}
1662	wusb_dev = __wusb_dev_get_by_usb_dev(wusbhc, urb->dev);
1663	if (wusb_dev == NULL) {
1664		mutex_unlock(&wusbhc->mutex);
1665		dev_err(&(urb->dev->dev), "%s: error wusb dev gone\n",
1666			__func__);
1667		goto error_dev_gone;
1668	}
1669	mutex_unlock(&wusbhc->mutex);
1670
1671	spin_lock_irqsave(&xfer->lock, flags);
1672	xfer->wusb_dev = wusb_dev;
1673	result = urb->status;
1674	if (urb->status != -EINPROGRESS) {
1675		dev_err(&(urb->dev->dev), "%s: error_dequeued\n", __func__);
1676		goto error_dequeued;
1677	}
1678
1679	result = __wa_xfer_setup(xfer, urb);
1680	if (result < 0) {
1681		dev_err(&(urb->dev->dev), "%s: error_xfer_setup\n", __func__);
1682		goto error_xfer_setup;
1683	}
1684	/*
1685	 * Get a xfer reference since __wa_xfer_submit starts asynchronous
1686	 * operations that may try to complete the xfer before this function
1687	 * exits.
1688	 */
1689	wa_xfer_get(xfer);
1690	result = __wa_xfer_submit(xfer);
1691	if (result < 0) {
1692		dev_err(&(urb->dev->dev), "%s: error_xfer_submit\n", __func__);
1693		goto error_xfer_submit;
1694	}
1695	spin_unlock_irqrestore(&xfer->lock, flags);
1696	wa_xfer_put(xfer);
1697	return 0;
1698
1699	/*
1700	 * this is basically wa_xfer_completion() broken up wa_xfer_giveback()
1701	 * does a wa_xfer_put() that will call wa_xfer_destroy() and undo
1702	 * setup().
1703	 */
1704error_xfer_setup:
1705error_dequeued:
1706	spin_unlock_irqrestore(&xfer->lock, flags);
1707	/* FIXME: segmentation broken, kills DWA */
1708	if (wusb_dev)
1709		wusb_dev_put(wusb_dev);
1710error_dev_gone:
1711	rpipe_put(xfer->ep->hcpriv);
1712error_rpipe_get:
1713	xfer->result = result;
1714	return result;
1715
1716error_xfer_submit:
1717	done = __wa_xfer_is_done(xfer);
1718	xfer->result = result;
1719	spin_unlock_irqrestore(&xfer->lock, flags);
1720	if (done)
1721		wa_xfer_completion(xfer);
1722	wa_xfer_put(xfer);
1723	/* return success since the completion routine will run. */
1724	return 0;
1725}
1726
1727/*
1728 * Execute the delayed transfers in the Wire Adapter @wa
1729 *
1730 * We need to be careful here, as dequeue() could be called in the
1731 * middle.  That's why we do the whole thing under the
1732 * wa->xfer_list_lock. If dequeue() jumps in, it first locks xfer->lock
1733 * and then checks the list -- so as we would be acquiring in inverse
1734 * order, we move the delayed list to a separate list while locked and then
1735 * submit them without the list lock held.
1736 */
1737void wa_urb_enqueue_run(struct work_struct *ws)
1738{
1739	struct wahc *wa = container_of(ws, struct wahc, xfer_enqueue_work);
1740	struct wa_xfer *xfer, *next;
1741	struct urb *urb;
1742	LIST_HEAD(tmp_list);
1743
1744	/* Create a copy of the wa->xfer_delayed_list while holding the lock */
1745	spin_lock_irq(&wa->xfer_list_lock);
1746	list_cut_position(&tmp_list, &wa->xfer_delayed_list,
1747			wa->xfer_delayed_list.prev);
1748	spin_unlock_irq(&wa->xfer_list_lock);
1749
1750	/*
1751	 * enqueue from temp list without list lock held since wa_urb_enqueue_b
1752	 * can take xfer->lock as well as lock mutexes.
1753	 */
1754	list_for_each_entry_safe(xfer, next, &tmp_list, list_node) {
1755		list_del_init(&xfer->list_node);
1756
1757		urb = xfer->urb;
1758		if (wa_urb_enqueue_b(xfer) < 0)
1759			wa_xfer_giveback(xfer);
1760		usb_put_urb(urb);	/* taken when queuing */
1761	}
1762}
1763EXPORT_SYMBOL_GPL(wa_urb_enqueue_run);
1764
1765/*
1766 * Process the errored transfers on the Wire Adapter outside of interrupt.
1767 */
1768void wa_process_errored_transfers_run(struct work_struct *ws)
1769{
1770	struct wahc *wa = container_of(ws, struct wahc, xfer_error_work);
1771	struct wa_xfer *xfer, *next;
1772	LIST_HEAD(tmp_list);
1773
1774	pr_info("%s: Run delayed STALL processing.\n", __func__);
1775
1776	/* Create a copy of the wa->xfer_errored_list while holding the lock */
1777	spin_lock_irq(&wa->xfer_list_lock);
1778	list_cut_position(&tmp_list, &wa->xfer_errored_list,
1779			wa->xfer_errored_list.prev);
1780	spin_unlock_irq(&wa->xfer_list_lock);
1781
1782	/*
1783	 * run rpipe_clear_feature_stalled from temp list without list lock
1784	 * held.
1785	 */
1786	list_for_each_entry_safe(xfer, next, &tmp_list, list_node) {
1787		struct usb_host_endpoint *ep;
1788		unsigned long flags;
1789		struct wa_rpipe *rpipe;
1790
1791		spin_lock_irqsave(&xfer->lock, flags);
1792		ep = xfer->ep;
1793		rpipe = ep->hcpriv;
1794		spin_unlock_irqrestore(&xfer->lock, flags);
1795
1796		/* clear RPIPE feature stalled without holding a lock. */
1797		rpipe_clear_feature_stalled(wa, ep);
1798
1799		/* complete the xfer. This removes it from the tmp list. */
1800		wa_xfer_completion(xfer);
1801
1802		/* check for work. */
1803		wa_xfer_delayed_run(rpipe);
1804	}
1805}
1806EXPORT_SYMBOL_GPL(wa_process_errored_transfers_run);
1807
1808/*
1809 * Submit a transfer to the Wire Adapter in a delayed way
1810 *
1811 * The process of enqueuing involves possible sleeps() [see
1812 * enqueue_b(), for the rpipe_get() and the mutex_lock()]. If we are
1813 * in an atomic section, we defer the enqueue_b() call--else we call direct.
1814 *
1815 * @urb: We own a reference to it done by the HCI Linux USB stack that
1816 *       will be given up by calling usb_hcd_giveback_urb() or by
1817 *       returning error from this function -> ergo we don't have to
1818 *       refcount it.
1819 */
1820int wa_urb_enqueue(struct wahc *wa, struct usb_host_endpoint *ep,
1821		   struct urb *urb, gfp_t gfp)
1822{
1823	int result;
1824	struct device *dev = &wa->usb_iface->dev;
1825	struct wa_xfer *xfer;
1826	unsigned long my_flags;
1827	unsigned cant_sleep = irqs_disabled() | in_atomic();
1828
1829	if ((urb->transfer_buffer == NULL)
1830	    && (urb->sg == NULL)
1831	    && !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
1832	    && urb->transfer_buffer_length != 0) {
1833		dev_err(dev, "BUG? urb %p: NULL xfer buffer & NODMA\n", urb);
1834		dump_stack();
1835	}
1836
1837	spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1838	result = usb_hcd_link_urb_to_ep(&(wa->wusb->usb_hcd), urb);
1839	spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1840	if (result < 0)
1841		goto error_link_urb;
1842
1843	result = -ENOMEM;
1844	xfer = kzalloc(sizeof(*xfer), gfp);
1845	if (xfer == NULL)
1846		goto error_kmalloc;
1847
1848	result = -ENOENT;
1849	if (urb->status != -EINPROGRESS)	/* cancelled */
1850		goto error_dequeued;		/* before starting? */
1851	wa_xfer_init(xfer);
1852	xfer->wa = wa_get(wa);
1853	xfer->urb = urb;
1854	xfer->gfp = gfp;
1855	xfer->ep = ep;
1856	urb->hcpriv = xfer;
1857
1858	dev_dbg(dev, "xfer %p urb %p pipe 0x%02x [%d bytes] %s %s %s\n",
1859		xfer, urb, urb->pipe, urb->transfer_buffer_length,
1860		urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP ? "dma" : "nodma",
1861		urb->pipe & USB_DIR_IN ? "inbound" : "outbound",
1862		cant_sleep ? "deferred" : "inline");
1863
1864	if (cant_sleep) {
1865		usb_get_urb(urb);
1866		spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1867		list_add_tail(&xfer->list_node, &wa->xfer_delayed_list);
1868		spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1869		queue_work(wusbd, &wa->xfer_enqueue_work);
1870	} else {
1871		result = wa_urb_enqueue_b(xfer);
1872		if (result < 0) {
1873			/*
1874			 * URB submit/enqueue failed.  Clean up, return an
1875			 * error and do not run the callback.  This avoids
1876			 * an infinite submit/complete loop.
1877			 */
1878			dev_err(dev, "%s: URB enqueue failed: %d\n",
1879			   __func__, result);
1880			wa_put(xfer->wa);
1881			wa_xfer_put(xfer);
1882			spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1883			usb_hcd_unlink_urb_from_ep(&(wa->wusb->usb_hcd), urb);
1884			spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1885			return result;
1886		}
1887	}
1888	return 0;
1889
1890error_dequeued:
1891	kfree(xfer);
1892error_kmalloc:
1893	spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
1894	usb_hcd_unlink_urb_from_ep(&(wa->wusb->usb_hcd), urb);
1895	spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
1896error_link_urb:
1897	return result;
1898}
1899EXPORT_SYMBOL_GPL(wa_urb_enqueue);
1900
1901/*
1902 * Dequeue a URB and make sure uwb_hcd_giveback_urb() [completion
1903 * handler] is called.
1904 *
1905 * Until a transfer goes successfully through wa_urb_enqueue() it
1906 * needs to be dequeued with completion calling; when stuck in delayed
1907 * or before wa_xfer_setup() is called, we need to do completion.
1908 *
1909 *  not setup  If there is no hcpriv yet, that means that that enqueue
1910 *             still had no time to set the xfer up. Because
1911 *             urb->status should be other than -EINPROGRESS,
1912 *             enqueue() will catch that and bail out.
1913 *
1914 * If the transfer has gone through setup, we just need to clean it
1915 * up. If it has gone through submit(), we have to abort it [with an
1916 * asynch request] and then make sure we cancel each segment.
1917 *
1918 */
1919int wa_urb_dequeue(struct wahc *wa, struct urb *urb, int status)
1920{
1921	unsigned long flags, flags2;
1922	struct wa_xfer *xfer;
1923	struct wa_seg *seg;
1924	struct wa_rpipe *rpipe;
1925	unsigned cnt, done = 0, xfer_abort_pending;
1926	unsigned rpipe_ready = 0;
1927	int result;
1928
1929	/* check if it is safe to unlink. */
1930	spin_lock_irqsave(&wa->xfer_list_lock, flags);
1931	result = usb_hcd_check_unlink_urb(&(wa->wusb->usb_hcd), urb, status);
1932	if ((result == 0) && urb->hcpriv) {
1933		/*
1934		 * Get a xfer ref to prevent a race with wa_xfer_giveback
1935		 * cleaning up the xfer while we are working with it.
1936		 */
1937		wa_xfer_get(urb->hcpriv);
1938	}
1939	spin_unlock_irqrestore(&wa->xfer_list_lock, flags);
1940	if (result)
1941		return result;
1942
1943	xfer = urb->hcpriv;
1944	if (xfer == NULL)
1945		return -ENOENT;
1946	spin_lock_irqsave(&xfer->lock, flags);
1947	pr_debug("%s: DEQUEUE xfer id 0x%08X\n", __func__, wa_xfer_id(xfer));
1948	rpipe = xfer->ep->hcpriv;
1949	if (rpipe == NULL) {
1950		pr_debug("%s: xfer %p id 0x%08X has no RPIPE.  %s",
1951			__func__, xfer, wa_xfer_id(xfer),
1952			"Probably already aborted.\n" );
1953		result = -ENOENT;
1954		goto out_unlock;
1955	}
1956	/*
1957	 * Check for done to avoid racing with wa_xfer_giveback and completing
1958	 * twice.
1959	 */
1960	if (__wa_xfer_is_done(xfer)) {
1961		pr_debug("%s: xfer %p id 0x%08X already done.\n", __func__,
1962			xfer, wa_xfer_id(xfer));
1963		result = -ENOENT;
1964		goto out_unlock;
1965	}
1966	/* Check the delayed list -> if there, release and complete */
1967	spin_lock_irqsave(&wa->xfer_list_lock, flags2);
1968	if (!list_empty(&xfer->list_node) && xfer->seg == NULL)
1969		goto dequeue_delayed;
1970	spin_unlock_irqrestore(&wa->xfer_list_lock, flags2);
1971	if (xfer->seg == NULL)  	/* still hasn't reached */
1972		goto out_unlock;	/* setup(), enqueue_b() completes */
1973	/* Ok, the xfer is in flight already, it's been setup and submitted.*/
1974	xfer_abort_pending = __wa_xfer_abort(xfer) >= 0;
1975	/*
1976	 * grab the rpipe->seg_lock here to prevent racing with
1977	 * __wa_xfer_delayed_run.
1978	 */
1979	spin_lock(&rpipe->seg_lock);
1980	for (cnt = 0; cnt < xfer->segs; cnt++) {
1981		seg = xfer->seg[cnt];
1982		pr_debug("%s: xfer id 0x%08X#%d status = %d\n",
1983			__func__, wa_xfer_id(xfer), cnt, seg->status);
1984		switch (seg->status) {
1985		case WA_SEG_NOTREADY:
1986		case WA_SEG_READY:
1987			printk(KERN_ERR "xfer %p#%u: dequeue bad state %u\n",
1988			       xfer, cnt, seg->status);
1989			WARN_ON(1);
1990			break;
1991		case WA_SEG_DELAYED:
1992			/*
1993			 * delete from rpipe delayed list.  If no segments on
1994			 * this xfer have been submitted, __wa_xfer_is_done will
1995			 * trigger a giveback below.  Otherwise, the submitted
1996			 * segments will be completed in the DTI interrupt.
1997			 */
1998			seg->status = WA_SEG_ABORTED;
1999			seg->result = -ENOENT;
2000			list_del(&seg->list_node);
2001			xfer->segs_done++;
2002			break;
2003		case WA_SEG_DONE:
2004		case WA_SEG_ERROR:
2005		case WA_SEG_ABORTED:
2006			break;
2007			/*
2008			 * The buf_in data for a segment in the
2009			 * WA_SEG_DTI_PENDING state is actively being read.
2010			 * Let wa_buf_in_cb handle it since it will be called
2011			 * and will increment xfer->segs_done.  Cleaning up
2012			 * here could cause wa_buf_in_cb to access the xfer
2013			 * after it has been completed/freed.
2014			 */
2015		case WA_SEG_DTI_PENDING:
2016			break;
2017			/*
2018			 * In the states below, the HWA device already knows
2019			 * about the transfer.  If an abort request was sent,
2020			 * allow the HWA to process it and wait for the
2021			 * results.  Otherwise, the DTI state and seg completed
2022			 * counts can get out of sync.
2023			 */
2024		case WA_SEG_SUBMITTED:
2025		case WA_SEG_PENDING:
2026			/*
2027			 * Check if the abort was successfully sent.  This could
2028			 * be false if the HWA has been removed but we haven't
2029			 * gotten the disconnect notification yet.
2030			 */
2031			if (!xfer_abort_pending) {
2032				seg->status = WA_SEG_ABORTED;
2033				rpipe_ready = rpipe_avail_inc(rpipe);
2034				xfer->segs_done++;
2035			}
2036			break;
2037		}
2038	}
2039	spin_unlock(&rpipe->seg_lock);
2040	xfer->result = urb->status;	/* -ENOENT or -ECONNRESET */
2041	done = __wa_xfer_is_done(xfer);
2042	spin_unlock_irqrestore(&xfer->lock, flags);
2043	if (done)
2044		wa_xfer_completion(xfer);
2045	if (rpipe_ready)
2046		wa_xfer_delayed_run(rpipe);
2047	wa_xfer_put(xfer);
2048	return result;
2049
2050out_unlock:
2051	spin_unlock_irqrestore(&xfer->lock, flags);
2052	wa_xfer_put(xfer);
2053	return result;
2054
2055dequeue_delayed:
2056	list_del_init(&xfer->list_node);
2057	spin_unlock_irqrestore(&wa->xfer_list_lock, flags2);
2058	xfer->result = urb->status;
2059	spin_unlock_irqrestore(&xfer->lock, flags);
2060	wa_xfer_giveback(xfer);
2061	wa_xfer_put(xfer);
2062	usb_put_urb(urb);		/* we got a ref in enqueue() */
2063	return 0;
2064}
2065EXPORT_SYMBOL_GPL(wa_urb_dequeue);
2066
2067/*
2068 * Translation from WA status codes (WUSB1.0 Table 8.15) to errno
2069 * codes
2070 *
2071 * Positive errno values are internal inconsistencies and should be
2072 * flagged louder. Negative are to be passed up to the user in the
2073 * normal way.
2074 *
2075 * @status: USB WA status code -- high two bits are stripped.
2076 */
2077static int wa_xfer_status_to_errno(u8 status)
2078{
2079	int errno;
2080	u8 real_status = status;
2081	static int xlat[] = {
2082		[WA_XFER_STATUS_SUCCESS] = 		0,
2083		[WA_XFER_STATUS_HALTED] = 		-EPIPE,
2084		[WA_XFER_STATUS_DATA_BUFFER_ERROR] = 	-ENOBUFS,
2085		[WA_XFER_STATUS_BABBLE] = 		-EOVERFLOW,
2086		[WA_XFER_RESERVED] = 			EINVAL,
2087		[WA_XFER_STATUS_NOT_FOUND] =		0,
2088		[WA_XFER_STATUS_INSUFFICIENT_RESOURCE] = -ENOMEM,
2089		[WA_XFER_STATUS_TRANSACTION_ERROR] = 	-EILSEQ,
2090		[WA_XFER_STATUS_ABORTED] =		-ENOENT,
2091		[WA_XFER_STATUS_RPIPE_NOT_READY] = 	EINVAL,
2092		[WA_XFER_INVALID_FORMAT] = 		EINVAL,
2093		[WA_XFER_UNEXPECTED_SEGMENT_NUMBER] = 	EINVAL,
2094		[WA_XFER_STATUS_RPIPE_TYPE_MISMATCH] = 	EINVAL,
2095	};
2096	status &= 0x3f;
2097
2098	if (status == 0)
2099		return 0;
2100	if (status >= ARRAY_SIZE(xlat)) {
2101		printk_ratelimited(KERN_ERR "%s(): BUG? "
2102			       "Unknown WA transfer status 0x%02x\n",
2103			       __func__, real_status);
2104		return -EINVAL;
2105	}
2106	errno = xlat[status];
2107	if (unlikely(errno > 0)) {
2108		printk_ratelimited(KERN_ERR "%s(): BUG? "
2109			       "Inconsistent WA status: 0x%02x\n",
2110			       __func__, real_status);
2111		errno = -errno;
2112	}
2113	return errno;
2114}
2115
2116/*
2117 * If a last segment flag and/or a transfer result error is encountered,
2118 * no other segment transfer results will be returned from the device.
2119 * Mark the remaining submitted or pending xfers as completed so that
2120 * the xfer will complete cleanly.
2121 *
2122 * xfer->lock must be held
2123 *
2124 */
2125static void wa_complete_remaining_xfer_segs(struct wa_xfer *xfer,
2126		int starting_index, enum wa_seg_status status)
2127{
2128	int index;
2129	struct wa_rpipe *rpipe = xfer->ep->hcpriv;
2130
2131	for (index = starting_index; index < xfer->segs_submitted; index++) {
2132		struct wa_seg *current_seg = xfer->seg[index];
2133
2134		BUG_ON(current_seg == NULL);
2135
2136		switch (current_seg->status) {
2137		case WA_SEG_SUBMITTED:
2138		case WA_SEG_PENDING:
2139		case WA_SEG_DTI_PENDING:
2140			rpipe_avail_inc(rpipe);
2141		/*
2142		 * do not increment RPIPE avail for the WA_SEG_DELAYED case
2143		 * since it has not been submitted to the RPIPE.
2144		 */
2145		/* fall through */
2146		case WA_SEG_DELAYED:
2147			xfer->segs_done++;
2148			current_seg->status = status;
2149			break;
2150		case WA_SEG_ABORTED:
2151			break;
2152		default:
2153			WARN(1, "%s: xfer 0x%08X#%d. bad seg status = %d\n",
2154				__func__, wa_xfer_id(xfer), index,
2155				current_seg->status);
2156			break;
2157		}
2158	}
2159}
2160
2161/* Populate the given urb based on the current isoc transfer state. */
2162static int __wa_populate_buf_in_urb_isoc(struct wahc *wa,
2163	struct urb *buf_in_urb, struct wa_xfer *xfer, struct wa_seg *seg)
2164{
2165	int urb_start_frame = seg->isoc_frame_index + seg->isoc_frame_offset;
2166	int seg_index, total_len = 0, urb_frame_index = urb_start_frame;
2167	struct usb_iso_packet_descriptor *iso_frame_desc =
2168						xfer->urb->iso_frame_desc;
2169	const int dti_packet_size = usb_endpoint_maxp(wa->dti_epd);
2170	int next_frame_contiguous;
2171	struct usb_iso_packet_descriptor *iso_frame;
2172
2173	BUG_ON(buf_in_urb->status == -EINPROGRESS);
2174
2175	/*
2176	 * If the current frame actual_length is contiguous with the next frame
2177	 * and actual_length is a multiple of the DTI endpoint max packet size,
2178	 * combine the current frame with the next frame in a single URB.  This
2179	 * reduces the number of URBs that must be submitted in that case.
2180	 */
2181	seg_index = seg->isoc_frame_index;
2182	do {
2183		next_frame_contiguous = 0;
2184
2185		iso_frame = &iso_frame_desc[urb_frame_index];
2186		total_len += iso_frame->actual_length;
2187		++urb_frame_index;
2188		++seg_index;
2189
2190		if (seg_index < seg->isoc_frame_count) {
2191			struct usb_iso_packet_descriptor *next_iso_frame;
2192
2193			next_iso_frame = &iso_frame_desc[urb_frame_index];
2194
2195			if ((iso_frame->offset + iso_frame->actual_length) ==
2196				next_iso_frame->offset)
2197				next_frame_contiguous = 1;
2198		}
2199	} while (next_frame_contiguous
2200			&& ((iso_frame->actual_length % dti_packet_size) == 0));
2201
2202	/* this should always be 0 before a resubmit. */
2203	buf_in_urb->num_mapped_sgs	= 0;
2204	buf_in_urb->transfer_dma = xfer->urb->transfer_dma +
2205		iso_frame_desc[urb_start_frame].offset;
2206	buf_in_urb->transfer_buffer_length = total_len;
2207	buf_in_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
2208	buf_in_urb->transfer_buffer = NULL;
2209	buf_in_urb->sg = NULL;
2210	buf_in_urb->num_sgs = 0;
2211	buf_in_urb->context = seg;
2212
2213	/* return the number of frames included in this URB. */
2214	return seg_index - seg->isoc_frame_index;
2215}
2216
2217/* Populate the given urb based on the current transfer state. */
2218static int wa_populate_buf_in_urb(struct urb *buf_in_urb, struct wa_xfer *xfer,
2219	unsigned int seg_idx, unsigned int bytes_transferred)
2220{
2221	int result = 0;
2222	struct wa_seg *seg = xfer->seg[seg_idx];
2223
2224	BUG_ON(buf_in_urb->status == -EINPROGRESS);
2225	/* this should always be 0 before a resubmit. */
2226	buf_in_urb->num_mapped_sgs	= 0;
2227
2228	if (xfer->is_dma) {
2229		buf_in_urb->transfer_dma = xfer->urb->transfer_dma
2230			+ (seg_idx * xfer->seg_size);
2231		buf_in_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
2232		buf_in_urb->transfer_buffer = NULL;
2233		buf_in_urb->sg = NULL;
2234		buf_in_urb->num_sgs = 0;
2235	} else {
2236		/* do buffer or SG processing. */
2237		buf_in_urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
2238
2239		if (xfer->urb->transfer_buffer) {
2240			buf_in_urb->transfer_buffer =
2241				xfer->urb->transfer_buffer
2242				+ (seg_idx * xfer->seg_size);
2243			buf_in_urb->sg = NULL;
2244			buf_in_urb->num_sgs = 0;
2245		} else {
2246			/* allocate an SG list to store seg_size bytes
2247				and copy the subset of the xfer->urb->sg
2248				that matches the buffer subset we are
2249				about to read. */
2250			buf_in_urb->sg = wa_xfer_create_subset_sg(
2251				xfer->urb->sg,
2252				seg_idx * xfer->seg_size,
2253				bytes_transferred,
2254				&(buf_in_urb->num_sgs));
2255
2256			if (!(buf_in_urb->sg)) {
2257				buf_in_urb->num_sgs	= 0;
2258				result = -ENOMEM;
2259			}
2260			buf_in_urb->transfer_buffer = NULL;
2261		}
2262	}
2263	buf_in_urb->transfer_buffer_length = bytes_transferred;
2264	buf_in_urb->context = seg;
2265
2266	return result;
2267}
2268
2269/*
2270 * Process a xfer result completion message
2271 *
2272 * inbound transfers: need to schedule a buf_in_urb read
2273 *
2274 * FIXME: this function needs to be broken up in parts
2275 */
2276static void wa_xfer_result_chew(struct wahc *wa, struct wa_xfer *xfer,
2277		struct wa_xfer_result *xfer_result)
2278{
2279	int result;
2280	struct device *dev = &wa->usb_iface->dev;
2281	unsigned long flags;
2282	unsigned int seg_idx;
2283	struct wa_seg *seg;
2284	struct wa_rpipe *rpipe;
2285	unsigned done = 0;
2286	u8 usb_status;
2287	unsigned rpipe_ready = 0;
2288	unsigned bytes_transferred = le32_to_cpu(xfer_result->dwTransferLength);
2289	struct urb *buf_in_urb = &(wa->buf_in_urbs[0]);
2290
2291	spin_lock_irqsave(&xfer->lock, flags);
2292	seg_idx = xfer_result->bTransferSegment & 0x7f;
2293	if (unlikely(seg_idx >= xfer->segs))
2294		goto error_bad_seg;
2295	seg = xfer->seg[seg_idx];
2296	rpipe = xfer->ep->hcpriv;
2297	usb_status = xfer_result->bTransferStatus;
2298	dev_dbg(dev, "xfer %p ID 0x%08X#%u: bTransferStatus 0x%02x (seg status %u)\n",
2299		xfer, wa_xfer_id(xfer), seg_idx, usb_status, seg->status);
2300	if (seg->status == WA_SEG_ABORTED
2301	    || seg->status == WA_SEG_ERROR)	/* already handled */
2302		goto segment_aborted;
2303	if (seg->status == WA_SEG_SUBMITTED)	/* ops, got here */
2304		seg->status = WA_SEG_PENDING;	/* before wa_seg{_dto}_cb() */
2305	if (seg->status != WA_SEG_PENDING) {
2306		if (printk_ratelimit())
2307			dev_err(dev, "xfer %p#%u: Bad segment state %u\n",
2308				xfer, seg_idx, seg->status);
2309		seg->status = WA_SEG_PENDING;	/* workaround/"fix" it */
2310	}
2311	if (usb_status & 0x80) {
2312		seg->result = wa_xfer_status_to_errno(usb_status);
2313		dev_err(dev, "DTI: xfer %p 0x%08X:#%u failed (0x%02x)\n",
2314			xfer, xfer->id, seg->index, usb_status);
2315		seg->status = ((usb_status & 0x7F) == WA_XFER_STATUS_ABORTED) ?
2316			WA_SEG_ABORTED : WA_SEG_ERROR;
2317		goto error_complete;
2318	}
2319	/* FIXME: we ignore warnings, tally them for stats */
2320	if (usb_status & 0x40) 		/* Warning?... */
2321		usb_status = 0;		/* ... pass */
2322	/*
2323	 * If the last segment bit is set, complete the remaining segments.
2324	 * When the current segment is completed, either in wa_buf_in_cb for
2325	 * transfers with data or below for no data, the xfer will complete.
2326	 */
2327	if (xfer_result->bTransferSegment & 0x80)
2328		wa_complete_remaining_xfer_segs(xfer, seg->index + 1,
2329			WA_SEG_DONE);
2330	if (usb_pipeisoc(xfer->urb->pipe)
2331		&& (le32_to_cpu(xfer_result->dwNumOfPackets) > 0)) {
2332		/* set up WA state to read the isoc packet status next. */
2333		wa->dti_isoc_xfer_in_progress = wa_xfer_id(xfer);
2334		wa->dti_isoc_xfer_seg = seg_idx;
2335		wa->dti_state = WA_DTI_ISOC_PACKET_STATUS_PENDING;
2336	} else if (xfer->is_inbound && !usb_pipeisoc(xfer->urb->pipe)
2337			&& (bytes_transferred > 0)) {
2338		/* IN data phase: read to buffer */
2339		seg->status = WA_SEG_DTI_PENDING;
2340		result = wa_populate_buf_in_urb(buf_in_urb, xfer, seg_idx,
2341			bytes_transferred);
2342		if (result < 0)
2343			goto error_buf_in_populate;
2344		++(wa->active_buf_in_urbs);
2345		result = usb_submit_urb(buf_in_urb, GFP_ATOMIC);
2346		if (result < 0) {
2347			--(wa->active_buf_in_urbs);
2348			goto error_submit_buf_in;
2349		}
2350	} else {
2351		/* OUT data phase or no data, complete it -- */
2352		seg->result = bytes_transferred;
2353		rpipe_ready = rpipe_avail_inc(rpipe);
2354		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_DONE);
2355	}
2356	spin_unlock_irqrestore(&xfer->lock, flags);
2357	if (done)
2358		wa_xfer_completion(xfer);
2359	if (rpipe_ready)
2360		wa_xfer_delayed_run(rpipe);
2361	return;
2362
2363error_submit_buf_in:
2364	if (edc_inc(&wa->dti_edc, EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
2365		dev_err(dev, "DTI: URB max acceptable errors "
2366			"exceeded, resetting device\n");
2367		wa_reset_all(wa);
2368	}
2369	if (printk_ratelimit())
2370		dev_err(dev, "xfer %p#%u: can't submit DTI data phase: %d\n",
2371			xfer, seg_idx, result);
2372	seg->result = result;
2373	kfree(buf_in_urb->sg);
2374	buf_in_urb->sg = NULL;
2375error_buf_in_populate:
2376	__wa_xfer_abort(xfer);
2377	seg->status = WA_SEG_ERROR;
2378error_complete:
2379	xfer->segs_done++;
2380	rpipe_ready = rpipe_avail_inc(rpipe);
2381	wa_complete_remaining_xfer_segs(xfer, seg->index + 1, seg->status);
2382	done = __wa_xfer_is_done(xfer);
2383	/*
2384	 * queue work item to clear STALL for control endpoints.
2385	 * Otherwise, let endpoint_reset take care of it.
2386	 */
2387	if (((usb_status & 0x3f) == WA_XFER_STATUS_HALTED) &&
2388		usb_endpoint_xfer_control(&xfer->ep->desc) &&
2389		done) {
2390
2391		dev_info(dev, "Control EP stall.  Queue delayed work.\n");
2392		spin_lock(&wa->xfer_list_lock);
2393		/* move xfer from xfer_list to xfer_errored_list. */
2394		list_move_tail(&xfer->list_node, &wa->xfer_errored_list);
2395		spin_unlock(&wa->xfer_list_lock);
2396		spin_unlock_irqrestore(&xfer->lock, flags);
2397		queue_work(wusbd, &wa->xfer_error_work);
2398	} else {
2399		spin_unlock_irqrestore(&xfer->lock, flags);
2400		if (done)
2401			wa_xfer_completion(xfer);
2402		if (rpipe_ready)
2403			wa_xfer_delayed_run(rpipe);
2404	}
2405
2406	return;
2407
2408error_bad_seg:
2409	spin_unlock_irqrestore(&xfer->lock, flags);
2410	wa_urb_dequeue(wa, xfer->urb, -ENOENT);
2411	if (printk_ratelimit())
2412		dev_err(dev, "xfer %p#%u: bad segment\n", xfer, seg_idx);
2413	if (edc_inc(&wa->dti_edc, EDC_MAX_ERRORS, EDC_ERROR_TIMEFRAME)) {
2414		dev_err(dev, "DTI: URB max acceptable errors "
2415			"exceeded, resetting device\n");
2416		wa_reset_all(wa);
2417	}
2418	return;
2419
2420segment_aborted:
2421	/* nothing to do, as the aborter did the completion */
2422	spin_unlock_irqrestore(&xfer->lock, flags);
2423}
2424
2425/*
2426 * Process a isochronous packet status message
2427 *
2428 * inbound transfers: need to schedule a buf_in_urb read
2429 */
2430static int wa_process_iso_packet_status(struct wahc *wa, struct urb *urb)
2431{
2432	struct device *dev = &wa->usb_iface->dev;
2433	struct wa_xfer_packet_status_hwaiso *packet_status;
2434	struct wa_xfer_packet_status_len_hwaiso *status_array;
2435	struct wa_xfer *xfer;
2436	unsigned long flags;
2437	struct wa_seg *seg;
2438	struct wa_rpipe *rpipe;
2439	unsigned done = 0, dti_busy = 0, data_frame_count = 0, seg_index;
2440	unsigned first_frame_index = 0, rpipe_ready = 0;
2441	int expected_size;
2442
2443	/* We have a xfer result buffer; check it */
2444	dev_dbg(dev, "DTI: isoc packet status %d bytes at %p\n",
2445		urb->actual_length, urb->transfer_buffer);
2446	packet_status = (struct wa_xfer_packet_status_hwaiso *)(wa->dti_buf);
2447	if (packet_status->bPacketType != WA_XFER_ISO_PACKET_STATUS) {
2448		dev_err(dev, "DTI Error: isoc packet status--bad type 0x%02x\n",
2449			packet_status->bPacketType);
2450		goto error_parse_buffer;
2451	}
2452	xfer = wa_xfer_get_by_id(wa, wa->dti_isoc_xfer_in_progress);
2453	if (xfer == NULL) {
2454		dev_err(dev, "DTI Error: isoc packet status--unknown xfer 0x%08x\n",
2455			wa->dti_isoc_xfer_in_progress);
2456		goto error_parse_buffer;
2457	}
2458	spin_lock_irqsave(&xfer->lock, flags);
2459	if (unlikely(wa->dti_isoc_xfer_seg >= xfer->segs))
2460		goto error_bad_seg;
2461	seg = xfer->seg[wa->dti_isoc_xfer_seg];
2462	rpipe = xfer->ep->hcpriv;
2463	expected_size = sizeof(*packet_status) +
2464			(sizeof(packet_status->PacketStatus[0]) *
2465			seg->isoc_frame_count);
2466	if (urb->actual_length != expected_size) {
2467		dev_err(dev, "DTI Error: isoc packet status--bad urb length (%d bytes vs %d needed)\n",
2468			urb->actual_length, expected_size);
2469		goto error_bad_seg;
2470	}
2471	if (le16_to_cpu(packet_status->wLength) != expected_size) {
2472		dev_err(dev, "DTI Error: isoc packet status--bad length %u\n",
2473			le16_to_cpu(packet_status->wLength));
2474		goto error_bad_seg;
2475	}
2476	/* write isoc packet status and lengths back to the xfer urb. */
2477	status_array = packet_status->PacketStatus;
2478	xfer->urb->start_frame =
2479		wa->wusb->usb_hcd.driver->get_frame_number(&wa->wusb->usb_hcd);
2480	for (seg_index = 0; seg_index < seg->isoc_frame_count; ++seg_index) {
2481		struct usb_iso_packet_descriptor *iso_frame_desc =
2482			xfer->urb->iso_frame_desc;
2483		const int xfer_frame_index =
2484			seg->isoc_frame_offset + seg_index;
2485
2486		iso_frame_desc[xfer_frame_index].status =
2487			wa_xfer_status_to_errno(
2488			le16_to_cpu(status_array[seg_index].PacketStatus));
2489		iso_frame_desc[xfer_frame_index].actual_length =
2490			le16_to_cpu(status_array[seg_index].PacketLength);
2491		/* track the number of frames successfully transferred. */
2492		if (iso_frame_desc[xfer_frame_index].actual_length > 0) {
2493			/* save the starting frame index for buf_in_urb. */
2494			if (!data_frame_count)
2495				first_frame_index = seg_index;
2496			++data_frame_count;
2497		}
2498	}
2499
2500	if (xfer->is_inbound && data_frame_count) {
2501		int result, total_frames_read = 0, urb_index = 0;
2502		struct urb *buf_in_urb;
2503
2504		/* IN data phase: read to buffer */
2505		seg->status = WA_SEG_DTI_PENDING;
2506
2507		/* start with the first frame with data. */
2508		seg->isoc_frame_index = first_frame_index;
2509		/* submit up to WA_MAX_BUF_IN_URBS read URBs. */
2510		do {
2511			int urb_frame_index, urb_frame_count;
2512			struct usb_iso_packet_descriptor *iso_frame_desc;
2513
2514			buf_in_urb = &(wa->buf_in_urbs[urb_index]);
2515			urb_frame_count = __wa_populate_buf_in_urb_isoc(wa,
2516				buf_in_urb, xfer, seg);
2517			/* advance frame index to start of next read URB. */
2518			seg->isoc_frame_index += urb_frame_count;
2519			total_frames_read += urb_frame_count;
2520
2521			++(wa->active_buf_in_urbs);
2522			result = usb_submit_urb(buf_in_urb, GFP_ATOMIC);
2523
2524			/* skip 0-byte frames. */
2525			urb_frame_index =
2526				seg->isoc_frame_offset + seg->isoc_frame_index;
2527			iso_frame_desc =
2528				&(xfer->urb->iso_frame_desc[urb_frame_index]);
2529			while ((seg->isoc_frame_index <
2530						seg->isoc_frame_count) &&
2531				 (iso_frame_desc->actual_length == 0)) {
2532				++(seg->isoc_frame_index);
2533				++iso_frame_desc;
2534			}
2535			++urb_index;
2536
2537		} while ((result == 0) && (urb_index < WA_MAX_BUF_IN_URBS)
2538				&& (seg->isoc_frame_index <
2539						seg->isoc_frame_count));
2540
2541		if (result < 0) {
2542			--(wa->active_buf_in_urbs);
2543			dev_err(dev, "DTI Error: Could not submit buf in URB (%d)",
2544				result);
2545			wa_reset_all(wa);
2546		} else if (data_frame_count > total_frames_read)
2547			/* If we need to read more frames, set DTI busy. */
2548			dti_busy = 1;
2549	} else {
2550		/* OUT transfer or no more IN data, complete it -- */
2551		rpipe_ready = rpipe_avail_inc(rpipe);
2552		done = __wa_xfer_mark_seg_as_done(xfer, seg, WA_SEG_DONE);
2553	}
2554	spin_unlock_irqrestore(&xfer->lock, flags);
2555	if (dti_busy)
2556		wa->dti_state = WA_DTI_BUF_IN_DATA_PENDING;
2557	else
2558		wa->dti_state = WA_DTI_TRANSFER_RESULT_PENDING;
2559	if (done)
2560		wa_xfer_completion(xfer);
2561	if (rpipe_ready)
2562		wa_xfer_delayed_run(rpipe);
2563	wa_xfer_put(xfer);
2564	return dti_busy;
2565
2566error_bad_seg:
2567	spin_unlock_irqrestore(&xfer->lock, flags);
2568	wa_xfer_put(xfer);
2569error_parse_buffer:
2570	return dti_busy;
2571}
2572
2573/*
2574 * Callback for the IN data phase
2575 *
2576 * If successful transition state; otherwise, take a note of the
2577 * error, mark this segment done and try completion.
2578 *
2579 * Note we don't access until we are sure that the transfer hasn't
2580 * been cancelled (ECONNRESET, ENOENT), which could mean that
2581 * seg->xfer could be already gone.
2582 */
2583static void wa_buf_in_cb(struct urb *urb)
2584{
2585	struct wa_seg *seg = urb->context;
2586	struct wa_xfer *xfer = seg->xfer;
2587	struct wahc *wa;
2588	struct device *dev;
2589	struct wa_rpipe *rpipe;
2590	unsigned rpipe_ready = 0, isoc_data_frame_count = 0;
2591	unsigned long flags;
2592	int resubmit_dti = 0, active_buf_in_urbs;
2593	u8 done = 0;
2594
2595	/* free the sg if it was used. */
2596	kfree(urb->sg);
2597	urb->sg = NULL;
2598
2599	spin_lock_irqsave(&xfer->lock, flags);
2600	wa = xfer->wa;
2601	dev = &wa->usb_iface->dev;
2602	--(wa->active_buf_in_urbs);
2603	active_buf_in_urbs = wa->active_buf_in_urbs;
2604	rpipe = xfer->ep->hcpriv;
2605
2606	if (usb_pipeisoc(xfer->urb->pipe)) {
2607		struct usb_iso_packet_descriptor *iso_frame_desc =
2608			xfer->urb->iso_frame_desc;
2609		int	seg_index;
2610
2611		/*
2612		 * Find the next isoc frame with data and count how many
2613		 * frames with data remain.
2614		 */
2615		seg_index = seg->isoc_frame_index;
2616		while (seg_index < seg->isoc_frame_count) {
2617			const int urb_frame_index =
2618				seg->isoc_frame_offset + seg_index;
2619
2620			if (iso_frame_desc[urb_frame_index].actual_length > 0) {
2621				/* save the index of the next frame with data */
2622				if (!isoc_data_frame_count)
2623					seg->isoc_frame_index = seg_index;
2624				++isoc_data_frame_count;
2625			}
2626			++seg_index;
2627		}
2628	}
2629	spin_unlock_irqrestore(&xfer->lock, flags);
2630
2631	switch (urb->status) {
2632	case 0:
2633		spin_lock_irqsave(&xfer->lock, flags);
2634
2635		seg->result += urb->actual_length;
2636		if (isoc_data_frame_count > 0) {
2637			int result, urb_frame_count;
2638
2639			/* submit a read URB for the next frame with data. */
2640			urb_frame_count = __wa_populate_buf_in_urb_isoc(wa, urb,
2641				 xfer, seg);
2642			/* advance index to start of next read URB. */
2643			seg->isoc_frame_index += urb_frame_count;
2644			++(wa->active_buf_in_urbs);
2645			result = usb_submit_urb(urb, GFP_ATOMIC);
2646			if (result < 0) {
2647				--(wa->active_buf_in_urbs);
2648				dev_err(dev, "DTI Error: Could not submit buf in URB (%d)",
2649					result);
2650				wa_reset_all(wa);
2651			}
2652			/*
2653			 * If we are in this callback and
2654			 * isoc_data_frame_count > 0, it means that the dti_urb
2655			 * submission was delayed in wa_dti_cb.  Once
2656			 * we submit the last buf_in_urb, we can submit the
2657			 * delayed dti_urb.
2658			 */
2659			  resubmit_dti = (isoc_data_frame_count ==
2660							urb_frame_count);
2661		} else if (active_buf_in_urbs == 0) {
2662			dev_dbg(dev,
2663				"xfer %p 0x%08X#%u: data in done (%zu bytes)\n",
2664				xfer, wa_xfer_id(xfer), seg->index,
2665				seg->result);
2666			rpipe_ready = rpipe_avail_inc(rpipe);
2667			done = __wa_xfer_mark_seg_as_done(xfer, seg,
2668					WA_SEG_DONE);
2669		}
2670		spin_unlock_irqrestore(&xfer->lock, flags);
2671		if (done)
2672			wa_xfer_completion(xfer);
2673		if (rpipe_ready)
2674			wa_xfer_delayed_run(rpipe);
2675		break;
2676	case -ECONNRESET:	/* URB unlinked; no need to do anything */
2677	case -ENOENT:		/* as it was done by the who unlinked us */
2678		break;
2679	default:		/* Other errors ... */
2680		/*
2681		 * Error on data buf read.  Only resubmit DTI if it hasn't
2682		 * already been done by previously hitting this error or by a
2683		 * successful completion of the previous buf_in_urb.
2684		 */
2685		resubmit_dti = wa->dti_state != WA_DTI_TRANSFER_RESULT_PENDING;
2686		spin_lock_irqsave(&xfer->lock, flags);
2687		if (printk_ratelimit())
2688			dev_err(dev, "xfer %p 0x%08X#%u: data in error %d\n",
2689				xfer, wa_xfer_id(xfer), seg->index,
2690				urb->status);
2691		if (edc_inc(&wa->nep_edc, EDC_MAX_ERRORS,
2692			    EDC_ERROR_TIMEFRAME)){
2693			dev_err(dev, "DTO: URB max acceptable errors "
2694				"exceeded, resetting device\n");
2695			wa_reset_all(wa);
2696		}
2697		seg->result = urb->status;
2698		rpipe_ready = rpipe_avail_inc(rpipe);
2699		if (active_buf_in_urbs == 0)
2700			done = __wa_xfer_mark_seg_as_done(xfer, seg,
2701				WA_SEG_ERROR);
2702		else
2703			__wa_xfer_abort(xfer);
2704		spin_unlock_irqrestore(&xfer->lock, flags);
2705		if (done)
2706			wa_xfer_completion(xfer);
2707		if (rpipe_ready)
2708			wa_xfer_delayed_run(rpipe);
2709	}
2710
2711	if (resubmit_dti) {
2712		int result;
2713
2714		wa->dti_state = WA_DTI_TRANSFER_RESULT_PENDING;
2715
2716		result = usb_submit_urb(wa->dti_urb, GFP_ATOMIC);
2717		if (result < 0) {
2718			dev_err(dev, "DTI Error: Could not submit DTI URB (%d)\n",
2719				result);
2720			wa_reset_all(wa);
2721		}
2722	}
2723}
2724
2725/*
2726 * Handle an incoming transfer result buffer
2727 *
2728 * Given a transfer result buffer, it completes the transfer (possibly
2729 * scheduling and buffer in read) and then resubmits the DTI URB for a
2730 * new transfer result read.
2731 *
2732 *
2733 * The xfer_result DTI URB state machine
2734 *
2735 * States: OFF | RXR (Read-Xfer-Result) | RBI (Read-Buffer-In)
2736 *
2737 * We start in OFF mode, the first xfer_result notification [through
2738 * wa_handle_notif_xfer()] moves us to RXR by posting the DTI-URB to
2739 * read.
2740 *
2741 * We receive a buffer -- if it is not a xfer_result, we complain and
2742 * repost the DTI-URB. If it is a xfer_result then do the xfer seg
2743 * request accounting. If it is an IN segment, we move to RBI and post
2744 * a BUF-IN-URB to the right buffer. The BUF-IN-URB callback will
2745 * repost the DTI-URB and move to RXR state. if there was no IN
2746 * segment, it will repost the DTI-URB.
2747 *
2748 * We go back to OFF when we detect a ENOENT or ESHUTDOWN (or too many
2749 * errors) in the URBs.
2750 */
2751static void wa_dti_cb(struct urb *urb)
2752{
2753	int result, dti_busy = 0;
2754	struct wahc *wa = urb->context;
2755	struct device *dev = &wa->usb_iface->dev;
2756	u32 xfer_id;
2757	u8 usb_status;
2758
2759	BUG_ON(wa->dti_urb != urb);
2760	switch (wa->dti_urb->status) {
2761	case 0:
2762		if (wa->dti_state == WA_DTI_TRANSFER_RESULT_PENDING) {
2763			struct wa_xfer_result *xfer_result;
2764			struct wa_xfer *xfer;
2765
2766			/* We have a xfer result buffer; check it */
2767			dev_dbg(dev, "DTI: xfer result %d bytes at %p\n",
2768				urb->actual_length, urb->transfer_buffer);
2769			if (urb->actual_length != sizeof(*xfer_result)) {
2770				dev_err(dev, "DTI Error: xfer result--bad size xfer result (%d bytes vs %zu needed)\n",
2771					urb->actual_length,
2772					sizeof(*xfer_result));
2773				break;
2774			}
2775			xfer_result = (struct wa_xfer_result *)(wa->dti_buf);
2776			if (xfer_result->hdr.bLength != sizeof(*xfer_result)) {
2777				dev_err(dev, "DTI Error: xfer result--bad header length %u\n",
2778					xfer_result->hdr.bLength);
2779				break;
2780			}
2781			if (xfer_result->hdr.bNotifyType != WA_XFER_RESULT) {
2782				dev_err(dev, "DTI Error: xfer result--bad header type 0x%02x\n",
2783					xfer_result->hdr.bNotifyType);
2784				break;
2785			}
2786			xfer_id = le32_to_cpu(xfer_result->dwTransferID);
2787			usb_status = xfer_result->bTransferStatus & 0x3f;
2788			if (usb_status == WA_XFER_STATUS_NOT_FOUND) {
2789				/* taken care of already */
2790				dev_dbg(dev, "%s: xfer 0x%08X#%u not found.\n",
2791					__func__, xfer_id,
2792					xfer_result->bTransferSegment & 0x7f);
2793				break;
2794			}
2795			xfer = wa_xfer_get_by_id(wa, xfer_id);
2796			if (xfer == NULL) {
2797				/* FIXME: transaction not found. */
2798				dev_err(dev, "DTI Error: xfer result--unknown xfer 0x%08x (status 0x%02x)\n",
2799					xfer_id, usb_status);
2800				break;
2801			}
2802			wa_xfer_result_chew(wa, xfer, xfer_result);
2803			wa_xfer_put(xfer);
2804		} else if (wa->dti_state == WA_DTI_ISOC_PACKET_STATUS_PENDING) {
2805			dti_busy = wa_process_iso_packet_status(wa, urb);
2806		} else {
2807			dev_err(dev, "DTI Error: unexpected EP state = %d\n",
2808				wa->dti_state);
2809		}
2810		break;
2811	case -ENOENT:		/* (we killed the URB)...so, no broadcast */
2812	case -ESHUTDOWN:	/* going away! */
2813		dev_dbg(dev, "DTI: going down! %d\n", urb->status);
2814		goto out;
2815	default:
2816		/* Unknown error */
2817		if (edc_inc(&wa->dti_edc, EDC_MAX_ERRORS,
2818			    EDC_ERROR_TIMEFRAME)) {
2819			dev_err(dev, "DTI: URB max acceptable errors "
2820				"exceeded, resetting device\n");
2821			wa_reset_all(wa);
2822			goto out;
2823		}
2824		if (printk_ratelimit())
2825			dev_err(dev, "DTI: URB error %d\n", urb->status);
2826		break;
2827	}
2828
2829	/* Resubmit the DTI URB if we are not busy processing isoc in frames. */
2830	if (!dti_busy) {
2831		result = usb_submit_urb(wa->dti_urb, GFP_ATOMIC);
2832		if (result < 0) {
2833			dev_err(dev, "DTI Error: Could not submit DTI URB (%d)\n",
2834				result);
2835			wa_reset_all(wa);
2836		}
2837	}
2838out:
2839	return;
2840}
2841
2842/*
2843 * Initialize the DTI URB for reading transfer result notifications and also
2844 * the buffer-in URB, for reading buffers. Then we just submit the DTI URB.
2845 */
2846int wa_dti_start(struct wahc *wa)
2847{
2848	const struct usb_endpoint_descriptor *dti_epd = wa->dti_epd;
2849	struct device *dev = &wa->usb_iface->dev;
2850	int result = -ENOMEM, index;
2851
2852	if (wa->dti_urb != NULL)	/* DTI URB already started */
2853		goto out;
2854
2855	wa->dti_urb = usb_alloc_urb(0, GFP_KERNEL);
2856	if (wa->dti_urb == NULL)
 
2857		goto error_dti_urb_alloc;
 
2858	usb_fill_bulk_urb(
2859		wa->dti_urb, wa->usb_dev,
2860		usb_rcvbulkpipe(wa->usb_dev, 0x80 | dti_epd->bEndpointAddress),
2861		wa->dti_buf, wa->dti_buf_size,
2862		wa_dti_cb, wa);
2863
2864	/* init the buf in URBs */
2865	for (index = 0; index < WA_MAX_BUF_IN_URBS; ++index) {
2866		usb_fill_bulk_urb(
2867			&(wa->buf_in_urbs[index]), wa->usb_dev,
2868			usb_rcvbulkpipe(wa->usb_dev,
2869				0x80 | dti_epd->bEndpointAddress),
2870			NULL, 0, wa_buf_in_cb, wa);
2871	}
2872	result = usb_submit_urb(wa->dti_urb, GFP_KERNEL);
2873	if (result < 0) {
2874		dev_err(dev, "DTI Error: Could not submit DTI URB (%d) resetting\n",
2875			result);
2876		goto error_dti_urb_submit;
2877	}
2878out:
2879	return 0;
2880
2881error_dti_urb_submit:
2882	usb_put_urb(wa->dti_urb);
2883	wa->dti_urb = NULL;
2884error_dti_urb_alloc:
2885	return result;
2886}
2887EXPORT_SYMBOL_GPL(wa_dti_start);
2888/*
2889 * Transfer complete notification
2890 *
2891 * Called from the notif.c code. We get a notification on EP2 saying
2892 * that some endpoint has some transfer result data available. We are
2893 * about to read it.
2894 *
2895 * To speed up things, we always have a URB reading the DTI URB; we
2896 * don't really set it up and start it until the first xfer complete
2897 * notification arrives, which is what we do here.
2898 *
2899 * Follow up in wa_dti_cb(), as that's where the whole state
2900 * machine starts.
2901 *
2902 * @wa shall be referenced
2903 */
2904void wa_handle_notif_xfer(struct wahc *wa, struct wa_notif_hdr *notif_hdr)
2905{
2906	struct device *dev = &wa->usb_iface->dev;
2907	struct wa_notif_xfer *notif_xfer;
2908	const struct usb_endpoint_descriptor *dti_epd = wa->dti_epd;
2909
2910	notif_xfer = container_of(notif_hdr, struct wa_notif_xfer, hdr);
2911	BUG_ON(notif_hdr->bNotifyType != WA_NOTIF_TRANSFER);
2912
2913	if ((0x80 | notif_xfer->bEndpoint) != dti_epd->bEndpointAddress) {
2914		/* FIXME: hardcoded limitation, adapt */
2915		dev_err(dev, "BUG: DTI ep is %u, not %u (hack me)\n",
2916			notif_xfer->bEndpoint, dti_epd->bEndpointAddress);
2917		goto error;
2918	}
2919
2920	/* attempt to start the DTI ep processing. */
2921	if (wa_dti_start(wa) < 0)
2922		goto error;
2923
2924	return;
2925
2926error:
2927	wa_reset_all(wa);
2928}