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v3.1
   1/*
   2 * USB Network driver infrastructure
   3 * Copyright (C) 2000-2005 by David Brownell
   4 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 */
  20
  21/*
  22 * This is a generic "USB networking" framework that works with several
  23 * kinds of full and high speed networking devices:  host-to-host cables,
  24 * smart usb peripherals, and actual Ethernet adapters.
  25 *
  26 * These devices usually differ in terms of control protocols (if they
  27 * even have one!) and sometimes they define new framing to wrap or batch
  28 * Ethernet packets.  Otherwise, they talk to USB pretty much the same,
  29 * so interface (un)binding, endpoint I/O queues, fault handling, and other
  30 * issues can usefully be addressed by this framework.
  31 */
  32
  33// #define	DEBUG			// error path messages, extra info
  34// #define	VERBOSE			// more; success messages
  35
  36#include <linux/module.h>
  37#include <linux/init.h>
  38#include <linux/netdevice.h>
  39#include <linux/etherdevice.h>
  40#include <linux/ctype.h>
  41#include <linux/ethtool.h>
  42#include <linux/workqueue.h>
  43#include <linux/mii.h>
  44#include <linux/usb.h>
  45#include <linux/usb/usbnet.h>
  46#include <linux/slab.h>
  47#include <linux/kernel.h>
  48#include <linux/pm_runtime.h>
  49
  50#define DRIVER_VERSION		"22-Aug-2005"
  51
  52
  53/*-------------------------------------------------------------------------*/
  54
  55/*
  56 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
  57 * Several dozen bytes of IPv4 data can fit in two such transactions.
  58 * One maximum size Ethernet packet takes twenty four of them.
  59 * For high speed, each frame comfortably fits almost 36 max size
  60 * Ethernet packets (so queues should be bigger).
  61 *
  62 * REVISIT qlens should be members of 'struct usbnet'; the goal is to
  63 * let the USB host controller be busy for 5msec or more before an irq
  64 * is required, under load.  Jumbograms change the equation.
  65 */
  66#define RX_MAX_QUEUE_MEMORY (60 * 1518)
  67#define	RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  68			(RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4)
  69#define	TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  70			(RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4)
  71
  72// reawaken network queue this soon after stopping; else watchdog barks
  73#define TX_TIMEOUT_JIFFIES	(5*HZ)
  74
  75// throttle rx/tx briefly after some faults, so khubd might disconnect()
  76// us (it polls at HZ/4 usually) before we report too many false errors.
  77#define THROTTLE_JIFFIES	(HZ/8)
  78
  79// between wakeups
  80#define UNLINK_TIMEOUT_MS	3
  81
  82/*-------------------------------------------------------------------------*/
  83
  84// randomly generated ethernet address
  85static u8	node_id [ETH_ALEN];
  86
  87static const char driver_name [] = "usbnet";
  88
  89/* use ethtool to change the level for any given device */
  90static int msg_level = -1;
  91module_param (msg_level, int, 0);
  92MODULE_PARM_DESC (msg_level, "Override default message level");
  93
  94/*-------------------------------------------------------------------------*/
  95
  96/* handles CDC Ethernet and many other network "bulk data" interfaces */
  97int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
  98{
  99	int				tmp;
 100	struct usb_host_interface	*alt = NULL;
 101	struct usb_host_endpoint	*in = NULL, *out = NULL;
 102	struct usb_host_endpoint	*status = NULL;
 103
 104	for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
 105		unsigned	ep;
 106
 107		in = out = status = NULL;
 108		alt = intf->altsetting + tmp;
 109
 110		/* take the first altsetting with in-bulk + out-bulk;
 111		 * remember any status endpoint, just in case;
 112		 * ignore other endpoints and altsettings.
 113		 */
 114		for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
 115			struct usb_host_endpoint	*e;
 116			int				intr = 0;
 117
 118			e = alt->endpoint + ep;
 119			switch (e->desc.bmAttributes) {
 120			case USB_ENDPOINT_XFER_INT:
 121				if (!usb_endpoint_dir_in(&e->desc))
 122					continue;
 123				intr = 1;
 124				/* FALLTHROUGH */
 125			case USB_ENDPOINT_XFER_BULK:
 126				break;
 127			default:
 128				continue;
 129			}
 130			if (usb_endpoint_dir_in(&e->desc)) {
 131				if (!intr && !in)
 132					in = e;
 133				else if (intr && !status)
 134					status = e;
 135			} else {
 136				if (!out)
 137					out = e;
 138			}
 139		}
 140		if (in && out)
 141			break;
 142	}
 143	if (!alt || !in || !out)
 144		return -EINVAL;
 145
 146	if (alt->desc.bAlternateSetting != 0 ||
 147	    !(dev->driver_info->flags & FLAG_NO_SETINT)) {
 148		tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
 149				alt->desc.bAlternateSetting);
 150		if (tmp < 0)
 151			return tmp;
 152	}
 153
 154	dev->in = usb_rcvbulkpipe (dev->udev,
 155			in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 156	dev->out = usb_sndbulkpipe (dev->udev,
 157			out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 158	dev->status = status;
 159	return 0;
 160}
 161EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
 162
 163int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
 164{
 165	int 		tmp, i;
 166	unsigned char	buf [13];
 167
 168	tmp = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
 169	if (tmp != 12) {
 170		dev_dbg(&dev->udev->dev,
 171			"bad MAC string %d fetch, %d\n", iMACAddress, tmp);
 172		if (tmp >= 0)
 173			tmp = -EINVAL;
 174		return tmp;
 175	}
 176	for (i = tmp = 0; i < 6; i++, tmp += 2)
 177		dev->net->dev_addr [i] =
 178			(hex_to_bin(buf[tmp]) << 4) + hex_to_bin(buf[tmp + 1]);
 179	return 0;
 180}
 181EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
 182
 183static void intr_complete (struct urb *urb);
 184
 185static int init_status (struct usbnet *dev, struct usb_interface *intf)
 186{
 187	char		*buf = NULL;
 188	unsigned	pipe = 0;
 189	unsigned	maxp;
 190	unsigned	period;
 191
 192	if (!dev->driver_info->status)
 193		return 0;
 194
 195	pipe = usb_rcvintpipe (dev->udev,
 196			dev->status->desc.bEndpointAddress
 197				& USB_ENDPOINT_NUMBER_MASK);
 198	maxp = usb_maxpacket (dev->udev, pipe, 0);
 199
 200	/* avoid 1 msec chatter:  min 8 msec poll rate */
 201	period = max ((int) dev->status->desc.bInterval,
 202		(dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
 203
 204	buf = kmalloc (maxp, GFP_KERNEL);
 205	if (buf) {
 206		dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
 207		if (!dev->interrupt) {
 208			kfree (buf);
 209			return -ENOMEM;
 210		} else {
 211			usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
 212				buf, maxp, intr_complete, dev, period);
 
 213			dev_dbg(&intf->dev,
 214				"status ep%din, %d bytes period %d\n",
 215				usb_pipeendpoint(pipe), maxp, period);
 216		}
 217	}
 218	return 0;
 219}
 220
 221/* Passes this packet up the stack, updating its accounting.
 222 * Some link protocols batch packets, so their rx_fixup paths
 223 * can return clones as well as just modify the original skb.
 224 */
 225void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
 226{
 227	int	status;
 228
 229	if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
 230		skb_queue_tail(&dev->rxq_pause, skb);
 231		return;
 232	}
 233
 234	skb->protocol = eth_type_trans (skb, dev->net);
 235	dev->net->stats.rx_packets++;
 236	dev->net->stats.rx_bytes += skb->len;
 237
 238	netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
 239		  skb->len + sizeof (struct ethhdr), skb->protocol);
 240	memset (skb->cb, 0, sizeof (struct skb_data));
 
 
 
 
 241	status = netif_rx (skb);
 242	if (status != NET_RX_SUCCESS)
 243		netif_dbg(dev, rx_err, dev->net,
 244			  "netif_rx status %d\n", status);
 245}
 246EXPORT_SYMBOL_GPL(usbnet_skb_return);
 247
 248
 249/*-------------------------------------------------------------------------
 250 *
 251 * Network Device Driver (peer link to "Host Device", from USB host)
 252 *
 253 *-------------------------------------------------------------------------*/
 254
 255int usbnet_change_mtu (struct net_device *net, int new_mtu)
 256{
 257	struct usbnet	*dev = netdev_priv(net);
 258	int		ll_mtu = new_mtu + net->hard_header_len;
 259	int		old_hard_mtu = dev->hard_mtu;
 260	int		old_rx_urb_size = dev->rx_urb_size;
 261
 262	if (new_mtu <= 0)
 263		return -EINVAL;
 264	// no second zero-length packet read wanted after mtu-sized packets
 265	if ((ll_mtu % dev->maxpacket) == 0)
 266		return -EDOM;
 267	net->mtu = new_mtu;
 268
 269	dev->hard_mtu = net->mtu + net->hard_header_len;
 270	if (dev->rx_urb_size == old_hard_mtu) {
 271		dev->rx_urb_size = dev->hard_mtu;
 272		if (dev->rx_urb_size > old_rx_urb_size)
 273			usbnet_unlink_rx_urbs(dev);
 274	}
 275
 276	return 0;
 277}
 278EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 279
 
 
 
 
 
 
 
 
 
 
 280/*-------------------------------------------------------------------------*/
 281
 282/* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 283 * completion callbacks.  2.5 should have fixed those bugs...
 284 */
 285
 286static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list)
 
 287{
 288	unsigned long		flags;
 
 
 289
 290	spin_lock_irqsave(&list->lock, flags);
 
 
 291	__skb_unlink(skb, list);
 292	spin_unlock(&list->lock);
 293	spin_lock(&dev->done.lock);
 294	__skb_queue_tail(&dev->done, skb);
 295	if (dev->done.qlen == 1)
 296		tasklet_schedule(&dev->bh);
 297	spin_unlock_irqrestore(&dev->done.lock, flags);
 
 298}
 299
 300/* some work can't be done in tasklets, so we use keventd
 301 *
 302 * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 303 * but tasklet_schedule() doesn't.  hope the failure is rare.
 304 */
 305void usbnet_defer_kevent (struct usbnet *dev, int work)
 306{
 307	set_bit (work, &dev->flags);
 308	if (!schedule_work (&dev->kevent))
 309		netdev_err(dev->net, "kevent %d may have been dropped\n", work);
 310	else
 311		netdev_dbg(dev->net, "kevent %d scheduled\n", work);
 312}
 313EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 314
 315/*-------------------------------------------------------------------------*/
 316
 317static void rx_complete (struct urb *urb);
 318
 319static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 320{
 321	struct sk_buff		*skb;
 322	struct skb_data		*entry;
 323	int			retval = 0;
 324	unsigned long		lockflags;
 325	size_t			size = dev->rx_urb_size;
 326
 327	if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) {
 
 328		netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
 329		usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 330		usb_free_urb (urb);
 331		return -ENOMEM;
 332	}
 333	skb_reserve (skb, NET_IP_ALIGN);
 334
 335	entry = (struct skb_data *) skb->cb;
 336	entry->urb = urb;
 337	entry->dev = dev;
 338	entry->state = rx_start;
 339	entry->length = 0;
 340
 341	usb_fill_bulk_urb (urb, dev->udev, dev->in,
 342		skb->data, size, rx_complete, skb);
 343
 344	spin_lock_irqsave (&dev->rxq.lock, lockflags);
 345
 346	if (netif_running (dev->net) &&
 347	    netif_device_present (dev->net) &&
 348	    !test_bit (EVENT_RX_HALT, &dev->flags) &&
 349	    !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
 350		switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 351		case -EPIPE:
 352			usbnet_defer_kevent (dev, EVENT_RX_HALT);
 353			break;
 354		case -ENOMEM:
 355			usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 356			break;
 357		case -ENODEV:
 358			netif_dbg(dev, ifdown, dev->net, "device gone\n");
 359			netif_device_detach (dev->net);
 360			break;
 361		case -EHOSTUNREACH:
 362			retval = -ENOLINK;
 363			break;
 364		default:
 365			netif_dbg(dev, rx_err, dev->net,
 366				  "rx submit, %d\n", retval);
 367			tasklet_schedule (&dev->bh);
 368			break;
 369		case 0:
 370			__skb_queue_tail (&dev->rxq, skb);
 371		}
 372	} else {
 373		netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
 374		retval = -ENOLINK;
 375	}
 376	spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 377	if (retval) {
 378		dev_kfree_skb_any (skb);
 379		usb_free_urb (urb);
 380	}
 381	return retval;
 382}
 383
 384
 385/*-------------------------------------------------------------------------*/
 386
 387static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 388{
 389	if (dev->driver_info->rx_fixup &&
 390	    !dev->driver_info->rx_fixup (dev, skb)) {
 391		/* With RX_ASSEMBLE, rx_fixup() must update counters */
 392		if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
 393			dev->net->stats.rx_errors++;
 394		goto done;
 395	}
 396	// else network stack removes extra byte if we forced a short packet
 397
 398	if (skb->len) {
 399		/* all data was already cloned from skb inside the driver */
 400		if (dev->driver_info->flags & FLAG_MULTI_PACKET)
 401			dev_kfree_skb_any(skb);
 402		else
 403			usbnet_skb_return(dev, skb);
 404		return;
 405	}
 406
 407	netif_dbg(dev, rx_err, dev->net, "drop\n");
 408	dev->net->stats.rx_errors++;
 409done:
 410	skb_queue_tail(&dev->done, skb);
 411}
 412
 413/*-------------------------------------------------------------------------*/
 414
 415static void rx_complete (struct urb *urb)
 416{
 417	struct sk_buff		*skb = (struct sk_buff *) urb->context;
 418	struct skb_data		*entry = (struct skb_data *) skb->cb;
 419	struct usbnet		*dev = entry->dev;
 420	int			urb_status = urb->status;
 
 421
 422	skb_put (skb, urb->actual_length);
 423	entry->state = rx_done;
 424	entry->urb = NULL;
 425
 426	switch (urb_status) {
 427	/* success */
 428	case 0:
 429		if (skb->len < dev->net->hard_header_len) {
 430			entry->state = rx_cleanup;
 431			dev->net->stats.rx_errors++;
 432			dev->net->stats.rx_length_errors++;
 433			netif_dbg(dev, rx_err, dev->net,
 434				  "rx length %d\n", skb->len);
 435		}
 436		break;
 437
 438	/* stalls need manual reset. this is rare ... except that
 439	 * when going through USB 2.0 TTs, unplug appears this way.
 440	 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 441	 * storm, recovering as needed.
 442	 */
 443	case -EPIPE:
 444		dev->net->stats.rx_errors++;
 445		usbnet_defer_kevent (dev, EVENT_RX_HALT);
 446		// FALLTHROUGH
 447
 448	/* software-driven interface shutdown */
 449	case -ECONNRESET:		/* async unlink */
 450	case -ESHUTDOWN:		/* hardware gone */
 451		netif_dbg(dev, ifdown, dev->net,
 452			  "rx shutdown, code %d\n", urb_status);
 453		goto block;
 454
 455	/* we get controller i/o faults during khubd disconnect() delays.
 456	 * throttle down resubmits, to avoid log floods; just temporarily,
 457	 * so we still recover when the fault isn't a khubd delay.
 458	 */
 459	case -EPROTO:
 460	case -ETIME:
 461	case -EILSEQ:
 462		dev->net->stats.rx_errors++;
 463		if (!timer_pending (&dev->delay)) {
 464			mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 465			netif_dbg(dev, link, dev->net,
 466				  "rx throttle %d\n", urb_status);
 467		}
 468block:
 469		entry->state = rx_cleanup;
 470		entry->urb = urb;
 471		urb = NULL;
 472		break;
 473
 474	/* data overrun ... flush fifo? */
 475	case -EOVERFLOW:
 476		dev->net->stats.rx_over_errors++;
 477		// FALLTHROUGH
 478
 479	default:
 480		entry->state = rx_cleanup;
 481		dev->net->stats.rx_errors++;
 482		netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
 483		break;
 484	}
 485
 486	defer_bh(dev, skb, &dev->rxq);
 487
 488	if (urb) {
 489		if (netif_running (dev->net) &&
 490		    !test_bit (EVENT_RX_HALT, &dev->flags)) {
 
 491			rx_submit (dev, urb, GFP_ATOMIC);
 
 492			return;
 493		}
 494		usb_free_urb (urb);
 495	}
 496	netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
 497}
 498
 499static void intr_complete (struct urb *urb)
 500{
 501	struct usbnet	*dev = urb->context;
 502	int		status = urb->status;
 503
 504	switch (status) {
 505	/* success */
 506	case 0:
 507		dev->driver_info->status(dev, urb);
 508		break;
 509
 510	/* software-driven interface shutdown */
 511	case -ENOENT:		/* urb killed */
 512	case -ESHUTDOWN:	/* hardware gone */
 513		netif_dbg(dev, ifdown, dev->net,
 514			  "intr shutdown, code %d\n", status);
 515		return;
 516
 517	/* NOTE:  not throttling like RX/TX, since this endpoint
 518	 * already polls infrequently
 519	 */
 520	default:
 521		netdev_dbg(dev->net, "intr status %d\n", status);
 522		break;
 523	}
 524
 525	if (!netif_running (dev->net))
 526		return;
 527
 528	memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
 529	status = usb_submit_urb (urb, GFP_ATOMIC);
 530	if (status != 0)
 531		netif_err(dev, timer, dev->net,
 532			  "intr resubmit --> %d\n", status);
 533}
 534
 535/*-------------------------------------------------------------------------*/
 536void usbnet_pause_rx(struct usbnet *dev)
 537{
 538	set_bit(EVENT_RX_PAUSED, &dev->flags);
 539
 540	netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
 541}
 542EXPORT_SYMBOL_GPL(usbnet_pause_rx);
 543
 544void usbnet_resume_rx(struct usbnet *dev)
 545{
 546	struct sk_buff *skb;
 547	int num = 0;
 548
 549	clear_bit(EVENT_RX_PAUSED, &dev->flags);
 550
 551	while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
 552		usbnet_skb_return(dev, skb);
 553		num++;
 554	}
 555
 556	tasklet_schedule(&dev->bh);
 557
 558	netif_dbg(dev, rx_status, dev->net,
 559		  "paused rx queue disabled, %d skbs requeued\n", num);
 560}
 561EXPORT_SYMBOL_GPL(usbnet_resume_rx);
 562
 563void usbnet_purge_paused_rxq(struct usbnet *dev)
 564{
 565	skb_queue_purge(&dev->rxq_pause);
 566}
 567EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
 568
 569/*-------------------------------------------------------------------------*/
 570
 571// unlink pending rx/tx; completion handlers do all other cleanup
 572
 573static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 574{
 575	unsigned long		flags;
 576	struct sk_buff		*skb, *skbnext;
 577	int			count = 0;
 578
 579	spin_lock_irqsave (&q->lock, flags);
 580	skb_queue_walk_safe(q, skb, skbnext) {
 581		struct skb_data		*entry;
 582		struct urb		*urb;
 583		int			retval;
 584
 585		entry = (struct skb_data *) skb->cb;
 
 
 
 
 
 
 
 586		urb = entry->urb;
 587
 
 
 
 
 
 
 
 
 
 588		// during some PM-driven resume scenarios,
 589		// these (async) unlinks complete immediately
 590		retval = usb_unlink_urb (urb);
 591		if (retval != -EINPROGRESS && retval != 0)
 592			netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
 593		else
 594			count++;
 
 
 595	}
 596	spin_unlock_irqrestore (&q->lock, flags);
 597	return count;
 598}
 599
 600// Flush all pending rx urbs
 601// minidrivers may need to do this when the MTU changes
 602
 603void usbnet_unlink_rx_urbs(struct usbnet *dev)
 604{
 605	if (netif_running(dev->net)) {
 606		(void) unlink_urbs (dev, &dev->rxq);
 607		tasklet_schedule(&dev->bh);
 608	}
 609}
 610EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 611
 612/*-------------------------------------------------------------------------*/
 613
 614// precondition: never called in_interrupt
 615static void usbnet_terminate_urbs(struct usbnet *dev)
 616{
 617	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(unlink_wakeup);
 618	DECLARE_WAITQUEUE(wait, current);
 619	int temp;
 620
 621	/* ensure there are no more active urbs */
 622	add_wait_queue(&unlink_wakeup, &wait);
 623	set_current_state(TASK_UNINTERRUPTIBLE);
 624	dev->wait = &unlink_wakeup;
 625	temp = unlink_urbs(dev, &dev->txq) +
 626		unlink_urbs(dev, &dev->rxq);
 627
 628	/* maybe wait for deletions to finish. */
 629	while (!skb_queue_empty(&dev->rxq)
 630		&& !skb_queue_empty(&dev->txq)
 631		&& !skb_queue_empty(&dev->done)) {
 632			schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
 633			set_current_state(TASK_UNINTERRUPTIBLE);
 634			netif_dbg(dev, ifdown, dev->net,
 635				  "waited for %d urb completions\n", temp);
 636	}
 637	set_current_state(TASK_RUNNING);
 638	dev->wait = NULL;
 639	remove_wait_queue(&unlink_wakeup, &wait);
 640}
 641
 642int usbnet_stop (struct net_device *net)
 643{
 644	struct usbnet		*dev = netdev_priv(net);
 645	struct driver_info	*info = dev->driver_info;
 646	int			retval;
 647
 648	clear_bit(EVENT_DEV_OPEN, &dev->flags);
 649	netif_stop_queue (net);
 650
 651	netif_info(dev, ifdown, dev->net,
 652		   "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
 653		   net->stats.rx_packets, net->stats.tx_packets,
 654		   net->stats.rx_errors, net->stats.tx_errors);
 655
 656	/* allow minidriver to stop correctly (wireless devices to turn off
 657	 * radio etc) */
 658	if (info->stop) {
 659		retval = info->stop(dev);
 660		if (retval < 0)
 661			netif_info(dev, ifdown, dev->net,
 662				   "stop fail (%d) usbnet usb-%s-%s, %s\n",
 663				   retval,
 664				   dev->udev->bus->bus_name, dev->udev->devpath,
 665				   info->description);
 666	}
 667
 668	if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
 669		usbnet_terminate_urbs(dev);
 670
 671	usb_kill_urb(dev->interrupt);
 672
 673	usbnet_purge_paused_rxq(dev);
 674
 675	/* deferred work (task, timer, softirq) must also stop.
 676	 * can't flush_scheduled_work() until we drop rtnl (later),
 677	 * else workers could deadlock; so make workers a NOP.
 678	 */
 679	dev->flags = 0;
 680	del_timer_sync (&dev->delay);
 681	tasklet_kill (&dev->bh);
 682	if (info->manage_power)
 683		info->manage_power(dev, 0);
 684	else
 685		usb_autopm_put_interface(dev->intf);
 686
 687	return 0;
 688}
 689EXPORT_SYMBOL_GPL(usbnet_stop);
 690
 691/*-------------------------------------------------------------------------*/
 692
 693// posts reads, and enables write queuing
 694
 695// precondition: never called in_interrupt
 696
 697int usbnet_open (struct net_device *net)
 698{
 699	struct usbnet		*dev = netdev_priv(net);
 700	int			retval;
 701	struct driver_info	*info = dev->driver_info;
 702
 703	if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 704		netif_info(dev, ifup, dev->net,
 705			   "resumption fail (%d) usbnet usb-%s-%s, %s\n",
 706			   retval,
 707			   dev->udev->bus->bus_name,
 708			   dev->udev->devpath,
 709			   info->description);
 710		goto done_nopm;
 711	}
 712
 713	// put into "known safe" state
 714	if (info->reset && (retval = info->reset (dev)) < 0) {
 715		netif_info(dev, ifup, dev->net,
 716			   "open reset fail (%d) usbnet usb-%s-%s, %s\n",
 717			   retval,
 718			   dev->udev->bus->bus_name,
 719			   dev->udev->devpath,
 720			   info->description);
 721		goto done;
 722	}
 723
 724	// insist peer be connected
 725	if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 726		netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
 727		goto done;
 728	}
 729
 730	/* start any status interrupt transfer */
 731	if (dev->interrupt) {
 732		retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
 733		if (retval < 0) {
 734			netif_err(dev, ifup, dev->net,
 735				  "intr submit %d\n", retval);
 736			goto done;
 737		}
 738	}
 739
 740	set_bit(EVENT_DEV_OPEN, &dev->flags);
 741	netif_start_queue (net);
 742	netif_info(dev, ifup, dev->net,
 743		   "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
 744		   (int)RX_QLEN(dev), (int)TX_QLEN(dev),
 745		   dev->net->mtu,
 746		   (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
 747		   (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
 748		   (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
 749		   (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
 750		   (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 751		   "simple");
 752
 753	// delay posting reads until we're fully open
 754	tasklet_schedule (&dev->bh);
 755	if (info->manage_power) {
 756		retval = info->manage_power(dev, 1);
 757		if (retval < 0)
 758			goto done;
 759		usb_autopm_put_interface(dev->intf);
 760	}
 761	return retval;
 762
 
 
 763done:
 764	usb_autopm_put_interface(dev->intf);
 765done_nopm:
 766	return retval;
 767}
 768EXPORT_SYMBOL_GPL(usbnet_open);
 769
 770/*-------------------------------------------------------------------------*/
 771
 772/* ethtool methods; minidrivers may need to add some more, but
 773 * they'll probably want to use this base set.
 774 */
 775
 776int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 777{
 778	struct usbnet *dev = netdev_priv(net);
 779
 780	if (!dev->mii.mdio_read)
 781		return -EOPNOTSUPP;
 782
 783	return mii_ethtool_gset(&dev->mii, cmd);
 784}
 785EXPORT_SYMBOL_GPL(usbnet_get_settings);
 786
 787int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 788{
 789	struct usbnet *dev = netdev_priv(net);
 790	int retval;
 791
 792	if (!dev->mii.mdio_write)
 793		return -EOPNOTSUPP;
 794
 795	retval = mii_ethtool_sset(&dev->mii, cmd);
 796
 797	/* link speed/duplex might have changed */
 798	if (dev->driver_info->link_reset)
 799		dev->driver_info->link_reset(dev);
 800
 801	return retval;
 802
 803}
 804EXPORT_SYMBOL_GPL(usbnet_set_settings);
 805
 806u32 usbnet_get_link (struct net_device *net)
 807{
 808	struct usbnet *dev = netdev_priv(net);
 809
 810	/* If a check_connect is defined, return its result */
 811	if (dev->driver_info->check_connect)
 812		return dev->driver_info->check_connect (dev) == 0;
 813
 814	/* if the device has mii operations, use those */
 815	if (dev->mii.mdio_read)
 816		return mii_link_ok(&dev->mii);
 817
 818	/* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 819	return ethtool_op_get_link(net);
 820}
 821EXPORT_SYMBOL_GPL(usbnet_get_link);
 822
 823int usbnet_nway_reset(struct net_device *net)
 824{
 825	struct usbnet *dev = netdev_priv(net);
 826
 827	if (!dev->mii.mdio_write)
 828		return -EOPNOTSUPP;
 829
 830	return mii_nway_restart(&dev->mii);
 831}
 832EXPORT_SYMBOL_GPL(usbnet_nway_reset);
 833
 834void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
 835{
 836	struct usbnet *dev = netdev_priv(net);
 837
 838	strncpy (info->driver, dev->driver_name, sizeof info->driver);
 839	strncpy (info->version, DRIVER_VERSION, sizeof info->version);
 840	strncpy (info->fw_version, dev->driver_info->description,
 841		sizeof info->fw_version);
 842	usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
 843}
 844EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
 845
 846u32 usbnet_get_msglevel (struct net_device *net)
 847{
 848	struct usbnet *dev = netdev_priv(net);
 849
 850	return dev->msg_enable;
 851}
 852EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
 853
 854void usbnet_set_msglevel (struct net_device *net, u32 level)
 855{
 856	struct usbnet *dev = netdev_priv(net);
 857
 858	dev->msg_enable = level;
 859}
 860EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
 861
 862/* drivers may override default ethtool_ops in their bind() routine */
 863static const struct ethtool_ops usbnet_ethtool_ops = {
 864	.get_settings		= usbnet_get_settings,
 865	.set_settings		= usbnet_set_settings,
 866	.get_link		= usbnet_get_link,
 867	.nway_reset		= usbnet_nway_reset,
 868	.get_drvinfo		= usbnet_get_drvinfo,
 869	.get_msglevel		= usbnet_get_msglevel,
 870	.set_msglevel		= usbnet_set_msglevel,
 
 871};
 872
 873/*-------------------------------------------------------------------------*/
 874
 875/* work that cannot be done in interrupt context uses keventd.
 876 *
 877 * NOTE:  with 2.5 we could do more of this using completion callbacks,
 878 * especially now that control transfers can be queued.
 879 */
 880static void
 881kevent (struct work_struct *work)
 882{
 883	struct usbnet		*dev =
 884		container_of(work, struct usbnet, kevent);
 885	int			status;
 886
 887	/* usb_clear_halt() needs a thread context */
 888	if (test_bit (EVENT_TX_HALT, &dev->flags)) {
 889		unlink_urbs (dev, &dev->txq);
 890		status = usb_autopm_get_interface(dev->intf);
 891		if (status < 0)
 892			goto fail_pipe;
 893		status = usb_clear_halt (dev->udev, dev->out);
 894		usb_autopm_put_interface(dev->intf);
 895		if (status < 0 &&
 896		    status != -EPIPE &&
 897		    status != -ESHUTDOWN) {
 898			if (netif_msg_tx_err (dev))
 899fail_pipe:
 900				netdev_err(dev->net, "can't clear tx halt, status %d\n",
 901					   status);
 902		} else {
 903			clear_bit (EVENT_TX_HALT, &dev->flags);
 904			if (status != -ESHUTDOWN)
 905				netif_wake_queue (dev->net);
 906		}
 907	}
 908	if (test_bit (EVENT_RX_HALT, &dev->flags)) {
 909		unlink_urbs (dev, &dev->rxq);
 910		status = usb_autopm_get_interface(dev->intf);
 911		if (status < 0)
 912			goto fail_halt;
 913		status = usb_clear_halt (dev->udev, dev->in);
 914		usb_autopm_put_interface(dev->intf);
 915		if (status < 0 &&
 916		    status != -EPIPE &&
 917		    status != -ESHUTDOWN) {
 918			if (netif_msg_rx_err (dev))
 919fail_halt:
 920				netdev_err(dev->net, "can't clear rx halt, status %d\n",
 921					   status);
 922		} else {
 923			clear_bit (EVENT_RX_HALT, &dev->flags);
 924			tasklet_schedule (&dev->bh);
 925		}
 926	}
 927
 928	/* tasklet could resubmit itself forever if memory is tight */
 929	if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
 930		struct urb	*urb = NULL;
 931		int resched = 1;
 932
 933		if (netif_running (dev->net))
 934			urb = usb_alloc_urb (0, GFP_KERNEL);
 935		else
 936			clear_bit (EVENT_RX_MEMORY, &dev->flags);
 937		if (urb != NULL) {
 938			clear_bit (EVENT_RX_MEMORY, &dev->flags);
 939			status = usb_autopm_get_interface(dev->intf);
 940			if (status < 0) {
 941				usb_free_urb(urb);
 942				goto fail_lowmem;
 943			}
 944			if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
 945				resched = 0;
 946			usb_autopm_put_interface(dev->intf);
 947fail_lowmem:
 948			if (resched)
 949				tasklet_schedule (&dev->bh);
 950		}
 951	}
 952
 953	if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
 954		struct driver_info	*info = dev->driver_info;
 955		int			retval = 0;
 956
 957		clear_bit (EVENT_LINK_RESET, &dev->flags);
 958		status = usb_autopm_get_interface(dev->intf);
 959		if (status < 0)
 960			goto skip_reset;
 961		if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
 962			usb_autopm_put_interface(dev->intf);
 963skip_reset:
 964			netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
 965				    retval,
 966				    dev->udev->bus->bus_name,
 967				    dev->udev->devpath,
 968				    info->description);
 969		} else {
 970			usb_autopm_put_interface(dev->intf);
 971		}
 972	}
 973
 974	if (dev->flags)
 975		netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
 976}
 977
 978/*-------------------------------------------------------------------------*/
 979
 980static void tx_complete (struct urb *urb)
 981{
 982	struct sk_buff		*skb = (struct sk_buff *) urb->context;
 983	struct skb_data		*entry = (struct skb_data *) skb->cb;
 984	struct usbnet		*dev = entry->dev;
 985
 986	if (urb->status == 0) {
 987		if (!(dev->driver_info->flags & FLAG_MULTI_PACKET))
 988			dev->net->stats.tx_packets++;
 989		dev->net->stats.tx_bytes += entry->length;
 990	} else {
 991		dev->net->stats.tx_errors++;
 992
 993		switch (urb->status) {
 994		case -EPIPE:
 995			usbnet_defer_kevent (dev, EVENT_TX_HALT);
 996			break;
 997
 998		/* software-driven interface shutdown */
 999		case -ECONNRESET:		// async unlink
1000		case -ESHUTDOWN:		// hardware gone
1001			break;
1002
1003		// like rx, tx gets controller i/o faults during khubd delays
1004		// and so it uses the same throttling mechanism.
1005		case -EPROTO:
1006		case -ETIME:
1007		case -EILSEQ:
1008			usb_mark_last_busy(dev->udev);
1009			if (!timer_pending (&dev->delay)) {
1010				mod_timer (&dev->delay,
1011					jiffies + THROTTLE_JIFFIES);
1012				netif_dbg(dev, link, dev->net,
1013					  "tx throttle %d\n", urb->status);
1014			}
1015			netif_stop_queue (dev->net);
1016			break;
1017		default:
1018			netif_dbg(dev, tx_err, dev->net,
1019				  "tx err %d\n", entry->urb->status);
1020			break;
1021		}
1022	}
1023
1024	usb_autopm_put_interface_async(dev->intf);
1025	urb->dev = NULL;
1026	entry->state = tx_done;
1027	defer_bh(dev, skb, &dev->txq);
1028}
1029
1030/*-------------------------------------------------------------------------*/
1031
1032void usbnet_tx_timeout (struct net_device *net)
1033{
1034	struct usbnet		*dev = netdev_priv(net);
1035
1036	unlink_urbs (dev, &dev->txq);
1037	tasklet_schedule (&dev->bh);
1038
1039	// FIXME: device recovery -- reset?
1040}
1041EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1042
1043/*-------------------------------------------------------------------------*/
1044
1045netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1046				     struct net_device *net)
1047{
1048	struct usbnet		*dev = netdev_priv(net);
1049	int			length;
1050	struct urb		*urb = NULL;
1051	struct skb_data		*entry;
1052	struct driver_info	*info = dev->driver_info;
1053	unsigned long		flags;
1054	int retval;
1055
 
 
 
1056	// some devices want funky USB-level framing, for
1057	// win32 driver (usually) and/or hardware quirks
1058	if (info->tx_fixup) {
1059		skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1060		if (!skb) {
1061			if (netif_msg_tx_err(dev)) {
1062				netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1063				goto drop;
1064			} else {
1065				/* cdc_ncm collected packet; waits for more */
1066				goto not_drop;
1067			}
1068		}
1069	}
1070	length = skb->len;
1071
1072	if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1073		netif_dbg(dev, tx_err, dev->net, "no urb\n");
1074		goto drop;
1075	}
1076
1077	entry = (struct skb_data *) skb->cb;
1078	entry->urb = urb;
1079	entry->dev = dev;
1080	entry->state = tx_start;
1081	entry->length = length;
1082
1083	usb_fill_bulk_urb (urb, dev->udev, dev->out,
1084			skb->data, skb->len, tx_complete, skb);
1085
1086	/* don't assume the hardware handles USB_ZERO_PACKET
1087	 * NOTE:  strictly conforming cdc-ether devices should expect
1088	 * the ZLP here, but ignore the one-byte packet.
1089	 * NOTE2: CDC NCM specification is different from CDC ECM when
1090	 * handling ZLP/short packets, so cdc_ncm driver will make short
1091	 * packet itself if needed.
1092	 */
1093	if (length % dev->maxpacket == 0) {
1094		if (!(info->flags & FLAG_SEND_ZLP)) {
1095			if (!(info->flags & FLAG_MULTI_PACKET)) {
1096				urb->transfer_buffer_length++;
1097				if (skb_tailroom(skb)) {
1098					skb->data[skb->len] = 0;
1099					__skb_put(skb, 1);
1100				}
1101			}
1102		} else
1103			urb->transfer_flags |= URB_ZERO_PACKET;
1104	}
1105
1106	spin_lock_irqsave(&dev->txq.lock, flags);
1107	retval = usb_autopm_get_interface_async(dev->intf);
1108	if (retval < 0) {
1109		spin_unlock_irqrestore(&dev->txq.lock, flags);
1110		goto drop;
1111	}
1112
1113#ifdef CONFIG_PM
1114	/* if this triggers the device is still a sleep */
1115	if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1116		/* transmission will be done in resume */
1117		usb_anchor_urb(urb, &dev->deferred);
1118		/* no use to process more packets */
1119		netif_stop_queue(net);
1120		spin_unlock_irqrestore(&dev->txq.lock, flags);
1121		netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1122		goto deferred;
1123	}
1124#endif
1125
1126	switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1127	case -EPIPE:
1128		netif_stop_queue (net);
1129		usbnet_defer_kevent (dev, EVENT_TX_HALT);
1130		usb_autopm_put_interface_async(dev->intf);
1131		break;
1132	default:
1133		usb_autopm_put_interface_async(dev->intf);
1134		netif_dbg(dev, tx_err, dev->net,
1135			  "tx: submit urb err %d\n", retval);
1136		break;
1137	case 0:
1138		net->trans_start = jiffies;
1139		__skb_queue_tail (&dev->txq, skb);
1140		if (dev->txq.qlen >= TX_QLEN (dev))
1141			netif_stop_queue (net);
1142	}
1143	spin_unlock_irqrestore (&dev->txq.lock, flags);
1144
1145	if (retval) {
1146		netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1147drop:
1148		dev->net->stats.tx_dropped++;
1149not_drop:
1150		if (skb)
1151			dev_kfree_skb_any (skb);
1152		usb_free_urb (urb);
1153	} else
1154		netif_dbg(dev, tx_queued, dev->net,
1155			  "> tx, len %d, type 0x%x\n", length, skb->protocol);
1156#ifdef CONFIG_PM
1157deferred:
1158#endif
1159	return NETDEV_TX_OK;
1160}
1161EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1162
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1163/*-------------------------------------------------------------------------*/
1164
1165// tasklet (work deferred from completions, in_irq) or timer
1166
1167static void usbnet_bh (unsigned long param)
1168{
1169	struct usbnet		*dev = (struct usbnet *) param;
1170	struct sk_buff		*skb;
1171	struct skb_data		*entry;
1172
1173	while ((skb = skb_dequeue (&dev->done))) {
1174		entry = (struct skb_data *) skb->cb;
1175		switch (entry->state) {
1176		case rx_done:
1177			entry->state = rx_cleanup;
1178			rx_process (dev, skb);
1179			continue;
1180		case tx_done:
1181		case rx_cleanup:
1182			usb_free_urb (entry->urb);
1183			dev_kfree_skb (skb);
1184			continue;
1185		default:
1186			netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1187		}
1188	}
1189
1190	// waiting for all pending urbs to complete?
1191	if (dev->wait) {
1192		if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1193			wake_up (dev->wait);
1194		}
1195
1196	// or are we maybe short a few urbs?
1197	} else if (netif_running (dev->net) &&
1198		   netif_device_present (dev->net) &&
1199		   !timer_pending (&dev->delay) &&
1200		   !test_bit (EVENT_RX_HALT, &dev->flags)) {
1201		int	temp = dev->rxq.qlen;
1202		int	qlen = RX_QLEN (dev);
1203
1204		if (temp < qlen) {
1205			struct urb	*urb;
1206			int		i;
1207
1208			// don't refill the queue all at once
1209			for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) {
1210				urb = usb_alloc_urb (0, GFP_ATOMIC);
1211				if (urb != NULL) {
1212					if (rx_submit (dev, urb, GFP_ATOMIC) ==
1213					    -ENOLINK)
1214						return;
1215				}
1216			}
1217			if (temp != dev->rxq.qlen)
1218				netif_dbg(dev, link, dev->net,
1219					  "rxqlen %d --> %d\n",
1220					  temp, dev->rxq.qlen);
1221			if (dev->rxq.qlen < qlen)
1222				tasklet_schedule (&dev->bh);
1223		}
1224		if (dev->txq.qlen < TX_QLEN (dev))
1225			netif_wake_queue (dev->net);
1226	}
1227}
1228
1229
1230/*-------------------------------------------------------------------------
1231 *
1232 * USB Device Driver support
1233 *
1234 *-------------------------------------------------------------------------*/
1235
1236// precondition: never called in_interrupt
1237
1238void usbnet_disconnect (struct usb_interface *intf)
1239{
1240	struct usbnet		*dev;
1241	struct usb_device	*xdev;
1242	struct net_device	*net;
1243
1244	dev = usb_get_intfdata(intf);
1245	usb_set_intfdata(intf, NULL);
1246	if (!dev)
1247		return;
1248
1249	xdev = interface_to_usbdev (intf);
1250
1251	netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1252		   intf->dev.driver->name,
1253		   xdev->bus->bus_name, xdev->devpath,
1254		   dev->driver_info->description);
1255
1256	net = dev->net;
1257	unregister_netdev (net);
1258
1259	cancel_work_sync(&dev->kevent);
1260
1261	if (dev->driver_info->unbind)
1262		dev->driver_info->unbind (dev, intf);
1263
1264	usb_kill_urb(dev->interrupt);
1265	usb_free_urb(dev->interrupt);
1266
1267	free_netdev(net);
1268	usb_put_dev (xdev);
1269}
1270EXPORT_SYMBOL_GPL(usbnet_disconnect);
1271
1272static const struct net_device_ops usbnet_netdev_ops = {
1273	.ndo_open		= usbnet_open,
1274	.ndo_stop		= usbnet_stop,
1275	.ndo_start_xmit		= usbnet_start_xmit,
1276	.ndo_tx_timeout		= usbnet_tx_timeout,
1277	.ndo_change_mtu		= usbnet_change_mtu,
1278	.ndo_set_mac_address 	= eth_mac_addr,
1279	.ndo_validate_addr	= eth_validate_addr,
1280};
1281
1282/*-------------------------------------------------------------------------*/
1283
1284// precondition: never called in_interrupt
1285
1286static struct device_type wlan_type = {
1287	.name	= "wlan",
1288};
1289
1290static struct device_type wwan_type = {
1291	.name	= "wwan",
1292};
1293
1294int
1295usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1296{
1297	struct usbnet			*dev;
1298	struct net_device		*net;
1299	struct usb_host_interface	*interface;
1300	struct driver_info		*info;
1301	struct usb_device		*xdev;
1302	int				status;
1303	const char			*name;
1304	struct usb_driver 	*driver = to_usb_driver(udev->dev.driver);
1305
1306	/* usbnet already took usb runtime pm, so have to enable the feature
1307	 * for usb interface, otherwise usb_autopm_get_interface may return
1308	 * failure if USB_SUSPEND(RUNTIME_PM) is enabled.
1309	 */
1310	if (!driver->supports_autosuspend) {
1311		driver->supports_autosuspend = 1;
1312		pm_runtime_enable(&udev->dev);
1313	}
1314
1315	name = udev->dev.driver->name;
1316	info = (struct driver_info *) prod->driver_info;
1317	if (!info) {
1318		dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1319		return -ENODEV;
1320	}
1321	xdev = interface_to_usbdev (udev);
1322	interface = udev->cur_altsetting;
1323
1324	usb_get_dev (xdev);
1325
1326	status = -ENOMEM;
1327
1328	// set up our own records
1329	net = alloc_etherdev(sizeof(*dev));
1330	if (!net) {
1331		dbg ("can't kmalloc dev");
1332		goto out;
1333	}
1334
1335	/* netdev_printk() needs this so do it as early as possible */
1336	SET_NETDEV_DEV(net, &udev->dev);
1337
1338	dev = netdev_priv(net);
1339	dev->udev = xdev;
1340	dev->intf = udev;
1341	dev->driver_info = info;
1342	dev->driver_name = name;
1343	dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1344				| NETIF_MSG_PROBE | NETIF_MSG_LINK);
1345	skb_queue_head_init (&dev->rxq);
1346	skb_queue_head_init (&dev->txq);
1347	skb_queue_head_init (&dev->done);
1348	skb_queue_head_init(&dev->rxq_pause);
1349	dev->bh.func = usbnet_bh;
1350	dev->bh.data = (unsigned long) dev;
1351	INIT_WORK (&dev->kevent, kevent);
1352	init_usb_anchor(&dev->deferred);
1353	dev->delay.function = usbnet_bh;
1354	dev->delay.data = (unsigned long) dev;
1355	init_timer (&dev->delay);
1356	mutex_init (&dev->phy_mutex);
1357
1358	dev->net = net;
1359	strcpy (net->name, "usb%d");
1360	memcpy (net->dev_addr, node_id, sizeof node_id);
1361
1362	/* rx and tx sides can use different message sizes;
1363	 * bind() should set rx_urb_size in that case.
1364	 */
1365	dev->hard_mtu = net->mtu + net->hard_header_len;
1366#if 0
1367// dma_supported() is deeply broken on almost all architectures
1368	// possible with some EHCI controllers
1369	if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1370		net->features |= NETIF_F_HIGHDMA;
1371#endif
1372
1373	net->netdev_ops = &usbnet_netdev_ops;
1374	net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1375	net->ethtool_ops = &usbnet_ethtool_ops;
1376
1377	// allow device-specific bind/init procedures
1378	// NOTE net->name still not usable ...
1379	if (info->bind) {
1380		status = info->bind (dev, udev);
1381		if (status < 0)
1382			goto out1;
1383
1384		// heuristic:  "usb%d" for links we know are two-host,
1385		// else "eth%d" when there's reasonable doubt.  userspace
1386		// can rename the link if it knows better.
1387		if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1388		    ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1389		     (net->dev_addr [0] & 0x02) == 0))
1390			strcpy (net->name, "eth%d");
1391		/* WLAN devices should always be named "wlan%d" */
1392		if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1393			strcpy(net->name, "wlan%d");
1394		/* WWAN devices should always be named "wwan%d" */
1395		if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1396			strcpy(net->name, "wwan%d");
1397
1398		/* maybe the remote can't receive an Ethernet MTU */
1399		if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1400			net->mtu = dev->hard_mtu - net->hard_header_len;
1401	} else if (!info->in || !info->out)
1402		status = usbnet_get_endpoints (dev, udev);
1403	else {
1404		dev->in = usb_rcvbulkpipe (xdev, info->in);
1405		dev->out = usb_sndbulkpipe (xdev, info->out);
1406		if (!(info->flags & FLAG_NO_SETINT))
1407			status = usb_set_interface (xdev,
1408				interface->desc.bInterfaceNumber,
1409				interface->desc.bAlternateSetting);
1410		else
1411			status = 0;
1412
1413	}
1414	if (status >= 0 && dev->status)
1415		status = init_status (dev, udev);
1416	if (status < 0)
1417		goto out3;
1418
1419	if (!dev->rx_urb_size)
1420		dev->rx_urb_size = dev->hard_mtu;
1421	dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1422
1423	if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1424		SET_NETDEV_DEVTYPE(net, &wlan_type);
1425	if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1426		SET_NETDEV_DEVTYPE(net, &wwan_type);
1427
1428	status = register_netdev (net);
1429	if (status)
1430		goto out3;
1431	netif_info(dev, probe, dev->net,
1432		   "register '%s' at usb-%s-%s, %s, %pM\n",
1433		   udev->dev.driver->name,
1434		   xdev->bus->bus_name, xdev->devpath,
1435		   dev->driver_info->description,
1436		   net->dev_addr);
1437
1438	// ok, it's ready to go.
1439	usb_set_intfdata (udev, dev);
1440
1441	netif_device_attach (net);
1442
1443	if (dev->driver_info->flags & FLAG_LINK_INTR)
1444		netif_carrier_off(net);
1445
1446	return 0;
1447
 
 
1448out3:
1449	if (info->unbind)
1450		info->unbind (dev, udev);
1451out1:
1452	free_netdev(net);
1453out:
1454	usb_put_dev(xdev);
1455	return status;
1456}
1457EXPORT_SYMBOL_GPL(usbnet_probe);
1458
1459/*-------------------------------------------------------------------------*/
1460
1461/*
1462 * suspend the whole driver as soon as the first interface is suspended
1463 * resume only when the last interface is resumed
1464 */
1465
1466int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1467{
1468	struct usbnet		*dev = usb_get_intfdata(intf);
1469
1470	if (!dev->suspend_count++) {
1471		spin_lock_irq(&dev->txq.lock);
1472		/* don't autosuspend while transmitting */
1473		if (dev->txq.qlen && (message.event & PM_EVENT_AUTO)) {
 
1474			spin_unlock_irq(&dev->txq.lock);
1475			return -EBUSY;
1476		} else {
1477			set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1478			spin_unlock_irq(&dev->txq.lock);
1479		}
1480		/*
1481		 * accelerate emptying of the rx and queues, to avoid
1482		 * having everything error out.
1483		 */
1484		netif_device_detach (dev->net);
1485		usbnet_terminate_urbs(dev);
1486		usb_kill_urb(dev->interrupt);
1487
1488		/*
1489		 * reattach so runtime management can use and
1490		 * wake the device
1491		 */
1492		netif_device_attach (dev->net);
1493	}
1494	return 0;
1495}
1496EXPORT_SYMBOL_GPL(usbnet_suspend);
1497
1498int usbnet_resume (struct usb_interface *intf)
1499{
1500	struct usbnet		*dev = usb_get_intfdata(intf);
1501	struct sk_buff          *skb;
1502	struct urb              *res;
1503	int                     retval;
1504
1505	if (!--dev->suspend_count) {
1506		/* resume interrupt URBs */
1507		if (dev->interrupt && test_bit(EVENT_DEV_OPEN, &dev->flags))
1508			usb_submit_urb(dev->interrupt, GFP_NOIO);
1509
1510		spin_lock_irq(&dev->txq.lock);
1511		while ((res = usb_get_from_anchor(&dev->deferred))) {
1512
1513			skb = (struct sk_buff *)res->context;
1514			retval = usb_submit_urb(res, GFP_ATOMIC);
1515			if (retval < 0) {
1516				dev_kfree_skb_any(skb);
1517				usb_free_urb(res);
1518				usb_autopm_put_interface_async(dev->intf);
1519			} else {
1520				dev->net->trans_start = jiffies;
1521				__skb_queue_tail(&dev->txq, skb);
1522			}
1523		}
1524
1525		smp_mb();
1526		clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1527		spin_unlock_irq(&dev->txq.lock);
1528
1529		if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
 
 
 
 
 
 
 
1530			if (!(dev->txq.qlen >= TX_QLEN(dev)))
1531				netif_start_queue(dev->net);
1532			tasklet_schedule (&dev->bh);
1533		}
1534	}
1535	return 0;
1536}
1537EXPORT_SYMBOL_GPL(usbnet_resume);
1538
1539
1540/*-------------------------------------------------------------------------*/
1541
1542static int __init usbnet_init(void)
1543{
1544	/* Compiler should optimize this out. */
1545	BUILD_BUG_ON(
1546		FIELD_SIZEOF(struct sk_buff, cb) < sizeof(struct skb_data));
1547
1548	random_ether_addr(node_id);
1549	return 0;
1550}
1551module_init(usbnet_init);
1552
1553static void __exit usbnet_exit(void)
1554{
1555}
1556module_exit(usbnet_exit);
1557
1558MODULE_AUTHOR("David Brownell");
1559MODULE_DESCRIPTION("USB network driver framework");
1560MODULE_LICENSE("GPL");
v3.5.6
   1/*
   2 * USB Network driver infrastructure
   3 * Copyright (C) 2000-2005 by David Brownell
   4 * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program; if not, write to the Free Software
  18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19 */
  20
  21/*
  22 * This is a generic "USB networking" framework that works with several
  23 * kinds of full and high speed networking devices:  host-to-host cables,
  24 * smart usb peripherals, and actual Ethernet adapters.
  25 *
  26 * These devices usually differ in terms of control protocols (if they
  27 * even have one!) and sometimes they define new framing to wrap or batch
  28 * Ethernet packets.  Otherwise, they talk to USB pretty much the same,
  29 * so interface (un)binding, endpoint I/O queues, fault handling, and other
  30 * issues can usefully be addressed by this framework.
  31 */
  32
  33// #define	DEBUG			// error path messages, extra info
  34// #define	VERBOSE			// more; success messages
  35
  36#include <linux/module.h>
  37#include <linux/init.h>
  38#include <linux/netdevice.h>
  39#include <linux/etherdevice.h>
  40#include <linux/ctype.h>
  41#include <linux/ethtool.h>
  42#include <linux/workqueue.h>
  43#include <linux/mii.h>
  44#include <linux/usb.h>
  45#include <linux/usb/usbnet.h>
  46#include <linux/slab.h>
  47#include <linux/kernel.h>
  48#include <linux/pm_runtime.h>
  49
  50#define DRIVER_VERSION		"22-Aug-2005"
  51
  52
  53/*-------------------------------------------------------------------------*/
  54
  55/*
  56 * Nineteen USB 1.1 max size bulk transactions per frame (ms), max.
  57 * Several dozen bytes of IPv4 data can fit in two such transactions.
  58 * One maximum size Ethernet packet takes twenty four of them.
  59 * For high speed, each frame comfortably fits almost 36 max size
  60 * Ethernet packets (so queues should be bigger).
  61 *
  62 * REVISIT qlens should be members of 'struct usbnet'; the goal is to
  63 * let the USB host controller be busy for 5msec or more before an irq
  64 * is required, under load.  Jumbograms change the equation.
  65 */
  66#define RX_MAX_QUEUE_MEMORY (60 * 1518)
  67#define	RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  68			(RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4)
  69#define	TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \
  70			(RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4)
  71
  72// reawaken network queue this soon after stopping; else watchdog barks
  73#define TX_TIMEOUT_JIFFIES	(5*HZ)
  74
  75// throttle rx/tx briefly after some faults, so khubd might disconnect()
  76// us (it polls at HZ/4 usually) before we report too many false errors.
  77#define THROTTLE_JIFFIES	(HZ/8)
  78
  79// between wakeups
  80#define UNLINK_TIMEOUT_MS	3
  81
  82/*-------------------------------------------------------------------------*/
  83
  84// randomly generated ethernet address
  85static u8	node_id [ETH_ALEN];
  86
  87static const char driver_name [] = "usbnet";
  88
  89/* use ethtool to change the level for any given device */
  90static int msg_level = -1;
  91module_param (msg_level, int, 0);
  92MODULE_PARM_DESC (msg_level, "Override default message level");
  93
  94/*-------------------------------------------------------------------------*/
  95
  96/* handles CDC Ethernet and many other network "bulk data" interfaces */
  97int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf)
  98{
  99	int				tmp;
 100	struct usb_host_interface	*alt = NULL;
 101	struct usb_host_endpoint	*in = NULL, *out = NULL;
 102	struct usb_host_endpoint	*status = NULL;
 103
 104	for (tmp = 0; tmp < intf->num_altsetting; tmp++) {
 105		unsigned	ep;
 106
 107		in = out = status = NULL;
 108		alt = intf->altsetting + tmp;
 109
 110		/* take the first altsetting with in-bulk + out-bulk;
 111		 * remember any status endpoint, just in case;
 112		 * ignore other endpoints and altsettings.
 113		 */
 114		for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) {
 115			struct usb_host_endpoint	*e;
 116			int				intr = 0;
 117
 118			e = alt->endpoint + ep;
 119			switch (e->desc.bmAttributes) {
 120			case USB_ENDPOINT_XFER_INT:
 121				if (!usb_endpoint_dir_in(&e->desc))
 122					continue;
 123				intr = 1;
 124				/* FALLTHROUGH */
 125			case USB_ENDPOINT_XFER_BULK:
 126				break;
 127			default:
 128				continue;
 129			}
 130			if (usb_endpoint_dir_in(&e->desc)) {
 131				if (!intr && !in)
 132					in = e;
 133				else if (intr && !status)
 134					status = e;
 135			} else {
 136				if (!out)
 137					out = e;
 138			}
 139		}
 140		if (in && out)
 141			break;
 142	}
 143	if (!alt || !in || !out)
 144		return -EINVAL;
 145
 146	if (alt->desc.bAlternateSetting != 0 ||
 147	    !(dev->driver_info->flags & FLAG_NO_SETINT)) {
 148		tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber,
 149				alt->desc.bAlternateSetting);
 150		if (tmp < 0)
 151			return tmp;
 152	}
 153
 154	dev->in = usb_rcvbulkpipe (dev->udev,
 155			in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 156	dev->out = usb_sndbulkpipe (dev->udev,
 157			out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
 158	dev->status = status;
 159	return 0;
 160}
 161EXPORT_SYMBOL_GPL(usbnet_get_endpoints);
 162
 163int usbnet_get_ethernet_addr(struct usbnet *dev, int iMACAddress)
 164{
 165	int 		tmp, i;
 166	unsigned char	buf [13];
 167
 168	tmp = usb_string(dev->udev, iMACAddress, buf, sizeof buf);
 169	if (tmp != 12) {
 170		dev_dbg(&dev->udev->dev,
 171			"bad MAC string %d fetch, %d\n", iMACAddress, tmp);
 172		if (tmp >= 0)
 173			tmp = -EINVAL;
 174		return tmp;
 175	}
 176	for (i = tmp = 0; i < 6; i++, tmp += 2)
 177		dev->net->dev_addr [i] =
 178			(hex_to_bin(buf[tmp]) << 4) + hex_to_bin(buf[tmp + 1]);
 179	return 0;
 180}
 181EXPORT_SYMBOL_GPL(usbnet_get_ethernet_addr);
 182
 183static void intr_complete (struct urb *urb);
 184
 185static int init_status (struct usbnet *dev, struct usb_interface *intf)
 186{
 187	char		*buf = NULL;
 188	unsigned	pipe = 0;
 189	unsigned	maxp;
 190	unsigned	period;
 191
 192	if (!dev->driver_info->status)
 193		return 0;
 194
 195	pipe = usb_rcvintpipe (dev->udev,
 196			dev->status->desc.bEndpointAddress
 197				& USB_ENDPOINT_NUMBER_MASK);
 198	maxp = usb_maxpacket (dev->udev, pipe, 0);
 199
 200	/* avoid 1 msec chatter:  min 8 msec poll rate */
 201	period = max ((int) dev->status->desc.bInterval,
 202		(dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3);
 203
 204	buf = kmalloc (maxp, GFP_KERNEL);
 205	if (buf) {
 206		dev->interrupt = usb_alloc_urb (0, GFP_KERNEL);
 207		if (!dev->interrupt) {
 208			kfree (buf);
 209			return -ENOMEM;
 210		} else {
 211			usb_fill_int_urb(dev->interrupt, dev->udev, pipe,
 212				buf, maxp, intr_complete, dev, period);
 213			dev->interrupt->transfer_flags |= URB_FREE_BUFFER;
 214			dev_dbg(&intf->dev,
 215				"status ep%din, %d bytes period %d\n",
 216				usb_pipeendpoint(pipe), maxp, period);
 217		}
 218	}
 219	return 0;
 220}
 221
 222/* Passes this packet up the stack, updating its accounting.
 223 * Some link protocols batch packets, so their rx_fixup paths
 224 * can return clones as well as just modify the original skb.
 225 */
 226void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb)
 227{
 228	int	status;
 229
 230	if (test_bit(EVENT_RX_PAUSED, &dev->flags)) {
 231		skb_queue_tail(&dev->rxq_pause, skb);
 232		return;
 233	}
 234
 235	skb->protocol = eth_type_trans (skb, dev->net);
 236	dev->net->stats.rx_packets++;
 237	dev->net->stats.rx_bytes += skb->len;
 238
 239	netif_dbg(dev, rx_status, dev->net, "< rx, len %zu, type 0x%x\n",
 240		  skb->len + sizeof (struct ethhdr), skb->protocol);
 241	memset (skb->cb, 0, sizeof (struct skb_data));
 242
 243	if (skb_defer_rx_timestamp(skb))
 244		return;
 245
 246	status = netif_rx (skb);
 247	if (status != NET_RX_SUCCESS)
 248		netif_dbg(dev, rx_err, dev->net,
 249			  "netif_rx status %d\n", status);
 250}
 251EXPORT_SYMBOL_GPL(usbnet_skb_return);
 252
 253
 254/*-------------------------------------------------------------------------
 255 *
 256 * Network Device Driver (peer link to "Host Device", from USB host)
 257 *
 258 *-------------------------------------------------------------------------*/
 259
 260int usbnet_change_mtu (struct net_device *net, int new_mtu)
 261{
 262	struct usbnet	*dev = netdev_priv(net);
 263	int		ll_mtu = new_mtu + net->hard_header_len;
 264	int		old_hard_mtu = dev->hard_mtu;
 265	int		old_rx_urb_size = dev->rx_urb_size;
 266
 267	if (new_mtu <= 0)
 268		return -EINVAL;
 269	// no second zero-length packet read wanted after mtu-sized packets
 270	if ((ll_mtu % dev->maxpacket) == 0)
 271		return -EDOM;
 272	net->mtu = new_mtu;
 273
 274	dev->hard_mtu = net->mtu + net->hard_header_len;
 275	if (dev->rx_urb_size == old_hard_mtu) {
 276		dev->rx_urb_size = dev->hard_mtu;
 277		if (dev->rx_urb_size > old_rx_urb_size)
 278			usbnet_unlink_rx_urbs(dev);
 279	}
 280
 281	return 0;
 282}
 283EXPORT_SYMBOL_GPL(usbnet_change_mtu);
 284
 285/* The caller must hold list->lock */
 286static void __usbnet_queue_skb(struct sk_buff_head *list,
 287			struct sk_buff *newsk, enum skb_state state)
 288{
 289	struct skb_data *entry = (struct skb_data *) newsk->cb;
 290
 291	__skb_queue_tail(list, newsk);
 292	entry->state = state;
 293}
 294
 295/*-------------------------------------------------------------------------*/
 296
 297/* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from
 298 * completion callbacks.  2.5 should have fixed those bugs...
 299 */
 300
 301static enum skb_state defer_bh(struct usbnet *dev, struct sk_buff *skb,
 302		struct sk_buff_head *list, enum skb_state state)
 303{
 304	unsigned long		flags;
 305	enum skb_state 		old_state;
 306	struct skb_data *entry = (struct skb_data *) skb->cb;
 307
 308	spin_lock_irqsave(&list->lock, flags);
 309	old_state = entry->state;
 310	entry->state = state;
 311	__skb_unlink(skb, list);
 312	spin_unlock(&list->lock);
 313	spin_lock(&dev->done.lock);
 314	__skb_queue_tail(&dev->done, skb);
 315	if (dev->done.qlen == 1)
 316		tasklet_schedule(&dev->bh);
 317	spin_unlock_irqrestore(&dev->done.lock, flags);
 318	return old_state;
 319}
 320
 321/* some work can't be done in tasklets, so we use keventd
 322 *
 323 * NOTE:  annoying asymmetry:  if it's active, schedule_work() fails,
 324 * but tasklet_schedule() doesn't.  hope the failure is rare.
 325 */
 326void usbnet_defer_kevent (struct usbnet *dev, int work)
 327{
 328	set_bit (work, &dev->flags);
 329	if (!schedule_work (&dev->kevent))
 330		netdev_err(dev->net, "kevent %d may have been dropped\n", work);
 331	else
 332		netdev_dbg(dev->net, "kevent %d scheduled\n", work);
 333}
 334EXPORT_SYMBOL_GPL(usbnet_defer_kevent);
 335
 336/*-------------------------------------------------------------------------*/
 337
 338static void rx_complete (struct urb *urb);
 339
 340static int rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags)
 341{
 342	struct sk_buff		*skb;
 343	struct skb_data		*entry;
 344	int			retval = 0;
 345	unsigned long		lockflags;
 346	size_t			size = dev->rx_urb_size;
 347
 348	skb = __netdev_alloc_skb_ip_align(dev->net, size, flags);
 349	if (!skb) {
 350		netif_dbg(dev, rx_err, dev->net, "no rx skb\n");
 351		usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 352		usb_free_urb (urb);
 353		return -ENOMEM;
 354	}
 
 355
 356	entry = (struct skb_data *) skb->cb;
 357	entry->urb = urb;
 358	entry->dev = dev;
 
 359	entry->length = 0;
 360
 361	usb_fill_bulk_urb (urb, dev->udev, dev->in,
 362		skb->data, size, rx_complete, skb);
 363
 364	spin_lock_irqsave (&dev->rxq.lock, lockflags);
 365
 366	if (netif_running (dev->net) &&
 367	    netif_device_present (dev->net) &&
 368	    !test_bit (EVENT_RX_HALT, &dev->flags) &&
 369	    !test_bit (EVENT_DEV_ASLEEP, &dev->flags)) {
 370		switch (retval = usb_submit_urb (urb, GFP_ATOMIC)) {
 371		case -EPIPE:
 372			usbnet_defer_kevent (dev, EVENT_RX_HALT);
 373			break;
 374		case -ENOMEM:
 375			usbnet_defer_kevent (dev, EVENT_RX_MEMORY);
 376			break;
 377		case -ENODEV:
 378			netif_dbg(dev, ifdown, dev->net, "device gone\n");
 379			netif_device_detach (dev->net);
 380			break;
 381		case -EHOSTUNREACH:
 382			retval = -ENOLINK;
 383			break;
 384		default:
 385			netif_dbg(dev, rx_err, dev->net,
 386				  "rx submit, %d\n", retval);
 387			tasklet_schedule (&dev->bh);
 388			break;
 389		case 0:
 390			__usbnet_queue_skb(&dev->rxq, skb, rx_start);
 391		}
 392	} else {
 393		netif_dbg(dev, ifdown, dev->net, "rx: stopped\n");
 394		retval = -ENOLINK;
 395	}
 396	spin_unlock_irqrestore (&dev->rxq.lock, lockflags);
 397	if (retval) {
 398		dev_kfree_skb_any (skb);
 399		usb_free_urb (urb);
 400	}
 401	return retval;
 402}
 403
 404
 405/*-------------------------------------------------------------------------*/
 406
 407static inline void rx_process (struct usbnet *dev, struct sk_buff *skb)
 408{
 409	if (dev->driver_info->rx_fixup &&
 410	    !dev->driver_info->rx_fixup (dev, skb)) {
 411		/* With RX_ASSEMBLE, rx_fixup() must update counters */
 412		if (!(dev->driver_info->flags & FLAG_RX_ASSEMBLE))
 413			dev->net->stats.rx_errors++;
 414		goto done;
 415	}
 416	// else network stack removes extra byte if we forced a short packet
 417
 418	if (skb->len) {
 419		/* all data was already cloned from skb inside the driver */
 420		if (dev->driver_info->flags & FLAG_MULTI_PACKET)
 421			dev_kfree_skb_any(skb);
 422		else
 423			usbnet_skb_return(dev, skb);
 424		return;
 425	}
 426
 427	netif_dbg(dev, rx_err, dev->net, "drop\n");
 428	dev->net->stats.rx_errors++;
 429done:
 430	skb_queue_tail(&dev->done, skb);
 431}
 432
 433/*-------------------------------------------------------------------------*/
 434
 435static void rx_complete (struct urb *urb)
 436{
 437	struct sk_buff		*skb = (struct sk_buff *) urb->context;
 438	struct skb_data		*entry = (struct skb_data *) skb->cb;
 439	struct usbnet		*dev = entry->dev;
 440	int			urb_status = urb->status;
 441	enum skb_state		state;
 442
 443	skb_put (skb, urb->actual_length);
 444	state = rx_done;
 445	entry->urb = NULL;
 446
 447	switch (urb_status) {
 448	/* success */
 449	case 0:
 450		if (skb->len < dev->net->hard_header_len) {
 451			state = rx_cleanup;
 452			dev->net->stats.rx_errors++;
 453			dev->net->stats.rx_length_errors++;
 454			netif_dbg(dev, rx_err, dev->net,
 455				  "rx length %d\n", skb->len);
 456		}
 457		break;
 458
 459	/* stalls need manual reset. this is rare ... except that
 460	 * when going through USB 2.0 TTs, unplug appears this way.
 461	 * we avoid the highspeed version of the ETIMEDOUT/EILSEQ
 462	 * storm, recovering as needed.
 463	 */
 464	case -EPIPE:
 465		dev->net->stats.rx_errors++;
 466		usbnet_defer_kevent (dev, EVENT_RX_HALT);
 467		// FALLTHROUGH
 468
 469	/* software-driven interface shutdown */
 470	case -ECONNRESET:		/* async unlink */
 471	case -ESHUTDOWN:		/* hardware gone */
 472		netif_dbg(dev, ifdown, dev->net,
 473			  "rx shutdown, code %d\n", urb_status);
 474		goto block;
 475
 476	/* we get controller i/o faults during khubd disconnect() delays.
 477	 * throttle down resubmits, to avoid log floods; just temporarily,
 478	 * so we still recover when the fault isn't a khubd delay.
 479	 */
 480	case -EPROTO:
 481	case -ETIME:
 482	case -EILSEQ:
 483		dev->net->stats.rx_errors++;
 484		if (!timer_pending (&dev->delay)) {
 485			mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES);
 486			netif_dbg(dev, link, dev->net,
 487				  "rx throttle %d\n", urb_status);
 488		}
 489block:
 490		state = rx_cleanup;
 491		entry->urb = urb;
 492		urb = NULL;
 493		break;
 494
 495	/* data overrun ... flush fifo? */
 496	case -EOVERFLOW:
 497		dev->net->stats.rx_over_errors++;
 498		// FALLTHROUGH
 499
 500	default:
 501		state = rx_cleanup;
 502		dev->net->stats.rx_errors++;
 503		netif_dbg(dev, rx_err, dev->net, "rx status %d\n", urb_status);
 504		break;
 505	}
 506
 507	state = defer_bh(dev, skb, &dev->rxq, state);
 508
 509	if (urb) {
 510		if (netif_running (dev->net) &&
 511		    !test_bit (EVENT_RX_HALT, &dev->flags) &&
 512		    state != unlink_start) {
 513			rx_submit (dev, urb, GFP_ATOMIC);
 514			usb_mark_last_busy(dev->udev);
 515			return;
 516		}
 517		usb_free_urb (urb);
 518	}
 519	netif_dbg(dev, rx_err, dev->net, "no read resubmitted\n");
 520}
 521
 522static void intr_complete (struct urb *urb)
 523{
 524	struct usbnet	*dev = urb->context;
 525	int		status = urb->status;
 526
 527	switch (status) {
 528	/* success */
 529	case 0:
 530		dev->driver_info->status(dev, urb);
 531		break;
 532
 533	/* software-driven interface shutdown */
 534	case -ENOENT:		/* urb killed */
 535	case -ESHUTDOWN:	/* hardware gone */
 536		netif_dbg(dev, ifdown, dev->net,
 537			  "intr shutdown, code %d\n", status);
 538		return;
 539
 540	/* NOTE:  not throttling like RX/TX, since this endpoint
 541	 * already polls infrequently
 542	 */
 543	default:
 544		netdev_dbg(dev->net, "intr status %d\n", status);
 545		break;
 546	}
 547
 548	if (!netif_running (dev->net))
 549		return;
 550
 551	memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
 552	status = usb_submit_urb (urb, GFP_ATOMIC);
 553	if (status != 0)
 554		netif_err(dev, timer, dev->net,
 555			  "intr resubmit --> %d\n", status);
 556}
 557
 558/*-------------------------------------------------------------------------*/
 559void usbnet_pause_rx(struct usbnet *dev)
 560{
 561	set_bit(EVENT_RX_PAUSED, &dev->flags);
 562
 563	netif_dbg(dev, rx_status, dev->net, "paused rx queue enabled\n");
 564}
 565EXPORT_SYMBOL_GPL(usbnet_pause_rx);
 566
 567void usbnet_resume_rx(struct usbnet *dev)
 568{
 569	struct sk_buff *skb;
 570	int num = 0;
 571
 572	clear_bit(EVENT_RX_PAUSED, &dev->flags);
 573
 574	while ((skb = skb_dequeue(&dev->rxq_pause)) != NULL) {
 575		usbnet_skb_return(dev, skb);
 576		num++;
 577	}
 578
 579	tasklet_schedule(&dev->bh);
 580
 581	netif_dbg(dev, rx_status, dev->net,
 582		  "paused rx queue disabled, %d skbs requeued\n", num);
 583}
 584EXPORT_SYMBOL_GPL(usbnet_resume_rx);
 585
 586void usbnet_purge_paused_rxq(struct usbnet *dev)
 587{
 588	skb_queue_purge(&dev->rxq_pause);
 589}
 590EXPORT_SYMBOL_GPL(usbnet_purge_paused_rxq);
 591
 592/*-------------------------------------------------------------------------*/
 593
 594// unlink pending rx/tx; completion handlers do all other cleanup
 595
 596static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q)
 597{
 598	unsigned long		flags;
 599	struct sk_buff		*skb;
 600	int			count = 0;
 601
 602	spin_lock_irqsave (&q->lock, flags);
 603	while (!skb_queue_empty(q)) {
 604		struct skb_data		*entry;
 605		struct urb		*urb;
 606		int			retval;
 607
 608		skb_queue_walk(q, skb) {
 609			entry = (struct skb_data *) skb->cb;
 610			if (entry->state != unlink_start)
 611				goto found;
 612		}
 613		break;
 614found:
 615		entry->state = unlink_start;
 616		urb = entry->urb;
 617
 618		/*
 619		 * Get reference count of the URB to avoid it to be
 620		 * freed during usb_unlink_urb, which may trigger
 621		 * use-after-free problem inside usb_unlink_urb since
 622		 * usb_unlink_urb is always racing with .complete
 623		 * handler(include defer_bh).
 624		 */
 625		usb_get_urb(urb);
 626		spin_unlock_irqrestore(&q->lock, flags);
 627		// during some PM-driven resume scenarios,
 628		// these (async) unlinks complete immediately
 629		retval = usb_unlink_urb (urb);
 630		if (retval != -EINPROGRESS && retval != 0)
 631			netdev_dbg(dev->net, "unlink urb err, %d\n", retval);
 632		else
 633			count++;
 634		usb_put_urb(urb);
 635		spin_lock_irqsave(&q->lock, flags);
 636	}
 637	spin_unlock_irqrestore (&q->lock, flags);
 638	return count;
 639}
 640
 641// Flush all pending rx urbs
 642// minidrivers may need to do this when the MTU changes
 643
 644void usbnet_unlink_rx_urbs(struct usbnet *dev)
 645{
 646	if (netif_running(dev->net)) {
 647		(void) unlink_urbs (dev, &dev->rxq);
 648		tasklet_schedule(&dev->bh);
 649	}
 650}
 651EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs);
 652
 653/*-------------------------------------------------------------------------*/
 654
 655// precondition: never called in_interrupt
 656static void usbnet_terminate_urbs(struct usbnet *dev)
 657{
 658	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(unlink_wakeup);
 659	DECLARE_WAITQUEUE(wait, current);
 660	int temp;
 661
 662	/* ensure there are no more active urbs */
 663	add_wait_queue(&unlink_wakeup, &wait);
 664	set_current_state(TASK_UNINTERRUPTIBLE);
 665	dev->wait = &unlink_wakeup;
 666	temp = unlink_urbs(dev, &dev->txq) +
 667		unlink_urbs(dev, &dev->rxq);
 668
 669	/* maybe wait for deletions to finish. */
 670	while (!skb_queue_empty(&dev->rxq)
 671		&& !skb_queue_empty(&dev->txq)
 672		&& !skb_queue_empty(&dev->done)) {
 673			schedule_timeout(msecs_to_jiffies(UNLINK_TIMEOUT_MS));
 674			set_current_state(TASK_UNINTERRUPTIBLE);
 675			netif_dbg(dev, ifdown, dev->net,
 676				  "waited for %d urb completions\n", temp);
 677	}
 678	set_current_state(TASK_RUNNING);
 679	dev->wait = NULL;
 680	remove_wait_queue(&unlink_wakeup, &wait);
 681}
 682
 683int usbnet_stop (struct net_device *net)
 684{
 685	struct usbnet		*dev = netdev_priv(net);
 686	struct driver_info	*info = dev->driver_info;
 687	int			retval;
 688
 689	clear_bit(EVENT_DEV_OPEN, &dev->flags);
 690	netif_stop_queue (net);
 691
 692	netif_info(dev, ifdown, dev->net,
 693		   "stop stats: rx/tx %lu/%lu, errs %lu/%lu\n",
 694		   net->stats.rx_packets, net->stats.tx_packets,
 695		   net->stats.rx_errors, net->stats.tx_errors);
 696
 697	/* allow minidriver to stop correctly (wireless devices to turn off
 698	 * radio etc) */
 699	if (info->stop) {
 700		retval = info->stop(dev);
 701		if (retval < 0)
 702			netif_info(dev, ifdown, dev->net,
 703				   "stop fail (%d) usbnet usb-%s-%s, %s\n",
 704				   retval,
 705				   dev->udev->bus->bus_name, dev->udev->devpath,
 706				   info->description);
 707	}
 708
 709	if (!(info->flags & FLAG_AVOID_UNLINK_URBS))
 710		usbnet_terminate_urbs(dev);
 711
 712	usb_kill_urb(dev->interrupt);
 713
 714	usbnet_purge_paused_rxq(dev);
 715
 716	/* deferred work (task, timer, softirq) must also stop.
 717	 * can't flush_scheduled_work() until we drop rtnl (later),
 718	 * else workers could deadlock; so make workers a NOP.
 719	 */
 720	dev->flags = 0;
 721	del_timer_sync (&dev->delay);
 722	tasklet_kill (&dev->bh);
 723	if (info->manage_power)
 724		info->manage_power(dev, 0);
 725	else
 726		usb_autopm_put_interface(dev->intf);
 727
 728	return 0;
 729}
 730EXPORT_SYMBOL_GPL(usbnet_stop);
 731
 732/*-------------------------------------------------------------------------*/
 733
 734// posts reads, and enables write queuing
 735
 736// precondition: never called in_interrupt
 737
 738int usbnet_open (struct net_device *net)
 739{
 740	struct usbnet		*dev = netdev_priv(net);
 741	int			retval;
 742	struct driver_info	*info = dev->driver_info;
 743
 744	if ((retval = usb_autopm_get_interface(dev->intf)) < 0) {
 745		netif_info(dev, ifup, dev->net,
 746			   "resumption fail (%d) usbnet usb-%s-%s, %s\n",
 747			   retval,
 748			   dev->udev->bus->bus_name,
 749			   dev->udev->devpath,
 750			   info->description);
 751		goto done_nopm;
 752	}
 753
 754	// put into "known safe" state
 755	if (info->reset && (retval = info->reset (dev)) < 0) {
 756		netif_info(dev, ifup, dev->net,
 757			   "open reset fail (%d) usbnet usb-%s-%s, %s\n",
 758			   retval,
 759			   dev->udev->bus->bus_name,
 760			   dev->udev->devpath,
 761			   info->description);
 762		goto done;
 763	}
 764
 765	// insist peer be connected
 766	if (info->check_connect && (retval = info->check_connect (dev)) < 0) {
 767		netif_dbg(dev, ifup, dev->net, "can't open; %d\n", retval);
 768		goto done;
 769	}
 770
 771	/* start any status interrupt transfer */
 772	if (dev->interrupt) {
 773		retval = usb_submit_urb (dev->interrupt, GFP_KERNEL);
 774		if (retval < 0) {
 775			netif_err(dev, ifup, dev->net,
 776				  "intr submit %d\n", retval);
 777			goto done;
 778		}
 779	}
 780
 781	set_bit(EVENT_DEV_OPEN, &dev->flags);
 782	netif_start_queue (net);
 783	netif_info(dev, ifup, dev->net,
 784		   "open: enable queueing (rx %d, tx %d) mtu %d %s framing\n",
 785		   (int)RX_QLEN(dev), (int)TX_QLEN(dev),
 786		   dev->net->mtu,
 787		   (dev->driver_info->flags & FLAG_FRAMING_NC) ? "NetChip" :
 788		   (dev->driver_info->flags & FLAG_FRAMING_GL) ? "GeneSys" :
 789		   (dev->driver_info->flags & FLAG_FRAMING_Z) ? "Zaurus" :
 790		   (dev->driver_info->flags & FLAG_FRAMING_RN) ? "RNDIS" :
 791		   (dev->driver_info->flags & FLAG_FRAMING_AX) ? "ASIX" :
 792		   "simple");
 793
 794	// delay posting reads until we're fully open
 795	tasklet_schedule (&dev->bh);
 796	if (info->manage_power) {
 797		retval = info->manage_power(dev, 1);
 798		if (retval < 0)
 799			goto done_manage_power_error;
 800		usb_autopm_put_interface(dev->intf);
 801	}
 802	return retval;
 803
 804done_manage_power_error:
 805	clear_bit(EVENT_DEV_OPEN, &dev->flags);
 806done:
 807	usb_autopm_put_interface(dev->intf);
 808done_nopm:
 809	return retval;
 810}
 811EXPORT_SYMBOL_GPL(usbnet_open);
 812
 813/*-------------------------------------------------------------------------*/
 814
 815/* ethtool methods; minidrivers may need to add some more, but
 816 * they'll probably want to use this base set.
 817 */
 818
 819int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd)
 820{
 821	struct usbnet *dev = netdev_priv(net);
 822
 823	if (!dev->mii.mdio_read)
 824		return -EOPNOTSUPP;
 825
 826	return mii_ethtool_gset(&dev->mii, cmd);
 827}
 828EXPORT_SYMBOL_GPL(usbnet_get_settings);
 829
 830int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd)
 831{
 832	struct usbnet *dev = netdev_priv(net);
 833	int retval;
 834
 835	if (!dev->mii.mdio_write)
 836		return -EOPNOTSUPP;
 837
 838	retval = mii_ethtool_sset(&dev->mii, cmd);
 839
 840	/* link speed/duplex might have changed */
 841	if (dev->driver_info->link_reset)
 842		dev->driver_info->link_reset(dev);
 843
 844	return retval;
 845
 846}
 847EXPORT_SYMBOL_GPL(usbnet_set_settings);
 848
 849u32 usbnet_get_link (struct net_device *net)
 850{
 851	struct usbnet *dev = netdev_priv(net);
 852
 853	/* If a check_connect is defined, return its result */
 854	if (dev->driver_info->check_connect)
 855		return dev->driver_info->check_connect (dev) == 0;
 856
 857	/* if the device has mii operations, use those */
 858	if (dev->mii.mdio_read)
 859		return mii_link_ok(&dev->mii);
 860
 861	/* Otherwise, dtrt for drivers calling netif_carrier_{on,off} */
 862	return ethtool_op_get_link(net);
 863}
 864EXPORT_SYMBOL_GPL(usbnet_get_link);
 865
 866int usbnet_nway_reset(struct net_device *net)
 867{
 868	struct usbnet *dev = netdev_priv(net);
 869
 870	if (!dev->mii.mdio_write)
 871		return -EOPNOTSUPP;
 872
 873	return mii_nway_restart(&dev->mii);
 874}
 875EXPORT_SYMBOL_GPL(usbnet_nway_reset);
 876
 877void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info)
 878{
 879	struct usbnet *dev = netdev_priv(net);
 880
 881	strlcpy (info->driver, dev->driver_name, sizeof info->driver);
 882	strlcpy (info->version, DRIVER_VERSION, sizeof info->version);
 883	strlcpy (info->fw_version, dev->driver_info->description,
 884		sizeof info->fw_version);
 885	usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info);
 886}
 887EXPORT_SYMBOL_GPL(usbnet_get_drvinfo);
 888
 889u32 usbnet_get_msglevel (struct net_device *net)
 890{
 891	struct usbnet *dev = netdev_priv(net);
 892
 893	return dev->msg_enable;
 894}
 895EXPORT_SYMBOL_GPL(usbnet_get_msglevel);
 896
 897void usbnet_set_msglevel (struct net_device *net, u32 level)
 898{
 899	struct usbnet *dev = netdev_priv(net);
 900
 901	dev->msg_enable = level;
 902}
 903EXPORT_SYMBOL_GPL(usbnet_set_msglevel);
 904
 905/* drivers may override default ethtool_ops in their bind() routine */
 906static const struct ethtool_ops usbnet_ethtool_ops = {
 907	.get_settings		= usbnet_get_settings,
 908	.set_settings		= usbnet_set_settings,
 909	.get_link		= usbnet_get_link,
 910	.nway_reset		= usbnet_nway_reset,
 911	.get_drvinfo		= usbnet_get_drvinfo,
 912	.get_msglevel		= usbnet_get_msglevel,
 913	.set_msglevel		= usbnet_set_msglevel,
 914	.get_ts_info		= ethtool_op_get_ts_info,
 915};
 916
 917/*-------------------------------------------------------------------------*/
 918
 919/* work that cannot be done in interrupt context uses keventd.
 920 *
 921 * NOTE:  with 2.5 we could do more of this using completion callbacks,
 922 * especially now that control transfers can be queued.
 923 */
 924static void
 925kevent (struct work_struct *work)
 926{
 927	struct usbnet		*dev =
 928		container_of(work, struct usbnet, kevent);
 929	int			status;
 930
 931	/* usb_clear_halt() needs a thread context */
 932	if (test_bit (EVENT_TX_HALT, &dev->flags)) {
 933		unlink_urbs (dev, &dev->txq);
 934		status = usb_autopm_get_interface(dev->intf);
 935		if (status < 0)
 936			goto fail_pipe;
 937		status = usb_clear_halt (dev->udev, dev->out);
 938		usb_autopm_put_interface(dev->intf);
 939		if (status < 0 &&
 940		    status != -EPIPE &&
 941		    status != -ESHUTDOWN) {
 942			if (netif_msg_tx_err (dev))
 943fail_pipe:
 944				netdev_err(dev->net, "can't clear tx halt, status %d\n",
 945					   status);
 946		} else {
 947			clear_bit (EVENT_TX_HALT, &dev->flags);
 948			if (status != -ESHUTDOWN)
 949				netif_wake_queue (dev->net);
 950		}
 951	}
 952	if (test_bit (EVENT_RX_HALT, &dev->flags)) {
 953		unlink_urbs (dev, &dev->rxq);
 954		status = usb_autopm_get_interface(dev->intf);
 955		if (status < 0)
 956			goto fail_halt;
 957		status = usb_clear_halt (dev->udev, dev->in);
 958		usb_autopm_put_interface(dev->intf);
 959		if (status < 0 &&
 960		    status != -EPIPE &&
 961		    status != -ESHUTDOWN) {
 962			if (netif_msg_rx_err (dev))
 963fail_halt:
 964				netdev_err(dev->net, "can't clear rx halt, status %d\n",
 965					   status);
 966		} else {
 967			clear_bit (EVENT_RX_HALT, &dev->flags);
 968			tasklet_schedule (&dev->bh);
 969		}
 970	}
 971
 972	/* tasklet could resubmit itself forever if memory is tight */
 973	if (test_bit (EVENT_RX_MEMORY, &dev->flags)) {
 974		struct urb	*urb = NULL;
 975		int resched = 1;
 976
 977		if (netif_running (dev->net))
 978			urb = usb_alloc_urb (0, GFP_KERNEL);
 979		else
 980			clear_bit (EVENT_RX_MEMORY, &dev->flags);
 981		if (urb != NULL) {
 982			clear_bit (EVENT_RX_MEMORY, &dev->flags);
 983			status = usb_autopm_get_interface(dev->intf);
 984			if (status < 0) {
 985				usb_free_urb(urb);
 986				goto fail_lowmem;
 987			}
 988			if (rx_submit (dev, urb, GFP_KERNEL) == -ENOLINK)
 989				resched = 0;
 990			usb_autopm_put_interface(dev->intf);
 991fail_lowmem:
 992			if (resched)
 993				tasklet_schedule (&dev->bh);
 994		}
 995	}
 996
 997	if (test_bit (EVENT_LINK_RESET, &dev->flags)) {
 998		struct driver_info	*info = dev->driver_info;
 999		int			retval = 0;
1000
1001		clear_bit (EVENT_LINK_RESET, &dev->flags);
1002		status = usb_autopm_get_interface(dev->intf);
1003		if (status < 0)
1004			goto skip_reset;
1005		if(info->link_reset && (retval = info->link_reset(dev)) < 0) {
1006			usb_autopm_put_interface(dev->intf);
1007skip_reset:
1008			netdev_info(dev->net, "link reset failed (%d) usbnet usb-%s-%s, %s\n",
1009				    retval,
1010				    dev->udev->bus->bus_name,
1011				    dev->udev->devpath,
1012				    info->description);
1013		} else {
1014			usb_autopm_put_interface(dev->intf);
1015		}
1016	}
1017
1018	if (dev->flags)
1019		netdev_dbg(dev->net, "kevent done, flags = 0x%lx\n", dev->flags);
1020}
1021
1022/*-------------------------------------------------------------------------*/
1023
1024static void tx_complete (struct urb *urb)
1025{
1026	struct sk_buff		*skb = (struct sk_buff *) urb->context;
1027	struct skb_data		*entry = (struct skb_data *) skb->cb;
1028	struct usbnet		*dev = entry->dev;
1029
1030	if (urb->status == 0) {
1031		if (!(dev->driver_info->flags & FLAG_MULTI_PACKET))
1032			dev->net->stats.tx_packets++;
1033		dev->net->stats.tx_bytes += entry->length;
1034	} else {
1035		dev->net->stats.tx_errors++;
1036
1037		switch (urb->status) {
1038		case -EPIPE:
1039			usbnet_defer_kevent (dev, EVENT_TX_HALT);
1040			break;
1041
1042		/* software-driven interface shutdown */
1043		case -ECONNRESET:		// async unlink
1044		case -ESHUTDOWN:		// hardware gone
1045			break;
1046
1047		// like rx, tx gets controller i/o faults during khubd delays
1048		// and so it uses the same throttling mechanism.
1049		case -EPROTO:
1050		case -ETIME:
1051		case -EILSEQ:
1052			usb_mark_last_busy(dev->udev);
1053			if (!timer_pending (&dev->delay)) {
1054				mod_timer (&dev->delay,
1055					jiffies + THROTTLE_JIFFIES);
1056				netif_dbg(dev, link, dev->net,
1057					  "tx throttle %d\n", urb->status);
1058			}
1059			netif_stop_queue (dev->net);
1060			break;
1061		default:
1062			netif_dbg(dev, tx_err, dev->net,
1063				  "tx err %d\n", entry->urb->status);
1064			break;
1065		}
1066	}
1067
1068	usb_autopm_put_interface_async(dev->intf);
1069	(void) defer_bh(dev, skb, &dev->txq, tx_done);
 
 
1070}
1071
1072/*-------------------------------------------------------------------------*/
1073
1074void usbnet_tx_timeout (struct net_device *net)
1075{
1076	struct usbnet		*dev = netdev_priv(net);
1077
1078	unlink_urbs (dev, &dev->txq);
1079	tasklet_schedule (&dev->bh);
1080
1081	// FIXME: device recovery -- reset?
1082}
1083EXPORT_SYMBOL_GPL(usbnet_tx_timeout);
1084
1085/*-------------------------------------------------------------------------*/
1086
1087netdev_tx_t usbnet_start_xmit (struct sk_buff *skb,
1088				     struct net_device *net)
1089{
1090	struct usbnet		*dev = netdev_priv(net);
1091	int			length;
1092	struct urb		*urb = NULL;
1093	struct skb_data		*entry;
1094	struct driver_info	*info = dev->driver_info;
1095	unsigned long		flags;
1096	int retval;
1097
1098	if (skb)
1099		skb_tx_timestamp(skb);
1100
1101	// some devices want funky USB-level framing, for
1102	// win32 driver (usually) and/or hardware quirks
1103	if (info->tx_fixup) {
1104		skb = info->tx_fixup (dev, skb, GFP_ATOMIC);
1105		if (!skb) {
1106			if (netif_msg_tx_err(dev)) {
1107				netif_dbg(dev, tx_err, dev->net, "can't tx_fixup skb\n");
1108				goto drop;
1109			} else {
1110				/* cdc_ncm collected packet; waits for more */
1111				goto not_drop;
1112			}
1113		}
1114	}
1115	length = skb->len;
1116
1117	if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) {
1118		netif_dbg(dev, tx_err, dev->net, "no urb\n");
1119		goto drop;
1120	}
1121
1122	entry = (struct skb_data *) skb->cb;
1123	entry->urb = urb;
1124	entry->dev = dev;
 
1125	entry->length = length;
1126
1127	usb_fill_bulk_urb (urb, dev->udev, dev->out,
1128			skb->data, skb->len, tx_complete, skb);
1129
1130	/* don't assume the hardware handles USB_ZERO_PACKET
1131	 * NOTE:  strictly conforming cdc-ether devices should expect
1132	 * the ZLP here, but ignore the one-byte packet.
1133	 * NOTE2: CDC NCM specification is different from CDC ECM when
1134	 * handling ZLP/short packets, so cdc_ncm driver will make short
1135	 * packet itself if needed.
1136	 */
1137	if (length % dev->maxpacket == 0) {
1138		if (!(info->flags & FLAG_SEND_ZLP)) {
1139			if (!(info->flags & FLAG_MULTI_PACKET)) {
1140				urb->transfer_buffer_length++;
1141				if (skb_tailroom(skb)) {
1142					skb->data[skb->len] = 0;
1143					__skb_put(skb, 1);
1144				}
1145			}
1146		} else
1147			urb->transfer_flags |= URB_ZERO_PACKET;
1148	}
1149
1150	spin_lock_irqsave(&dev->txq.lock, flags);
1151	retval = usb_autopm_get_interface_async(dev->intf);
1152	if (retval < 0) {
1153		spin_unlock_irqrestore(&dev->txq.lock, flags);
1154		goto drop;
1155	}
1156
1157#ifdef CONFIG_PM
1158	/* if this triggers the device is still a sleep */
1159	if (test_bit(EVENT_DEV_ASLEEP, &dev->flags)) {
1160		/* transmission will be done in resume */
1161		usb_anchor_urb(urb, &dev->deferred);
1162		/* no use to process more packets */
1163		netif_stop_queue(net);
1164		spin_unlock_irqrestore(&dev->txq.lock, flags);
1165		netdev_dbg(dev->net, "Delaying transmission for resumption\n");
1166		goto deferred;
1167	}
1168#endif
1169
1170	switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) {
1171	case -EPIPE:
1172		netif_stop_queue (net);
1173		usbnet_defer_kevent (dev, EVENT_TX_HALT);
1174		usb_autopm_put_interface_async(dev->intf);
1175		break;
1176	default:
1177		usb_autopm_put_interface_async(dev->intf);
1178		netif_dbg(dev, tx_err, dev->net,
1179			  "tx: submit urb err %d\n", retval);
1180		break;
1181	case 0:
1182		net->trans_start = jiffies;
1183		__usbnet_queue_skb(&dev->txq, skb, tx_start);
1184		if (dev->txq.qlen >= TX_QLEN (dev))
1185			netif_stop_queue (net);
1186	}
1187	spin_unlock_irqrestore (&dev->txq.lock, flags);
1188
1189	if (retval) {
1190		netif_dbg(dev, tx_err, dev->net, "drop, code %d\n", retval);
1191drop:
1192		dev->net->stats.tx_dropped++;
1193not_drop:
1194		if (skb)
1195			dev_kfree_skb_any (skb);
1196		usb_free_urb (urb);
1197	} else
1198		netif_dbg(dev, tx_queued, dev->net,
1199			  "> tx, len %d, type 0x%x\n", length, skb->protocol);
1200#ifdef CONFIG_PM
1201deferred:
1202#endif
1203	return NETDEV_TX_OK;
1204}
1205EXPORT_SYMBOL_GPL(usbnet_start_xmit);
1206
1207static int rx_alloc_submit(struct usbnet *dev, gfp_t flags)
1208{
1209	struct urb	*urb;
1210	int		i;
1211	int		ret = 0;
1212
1213	/* don't refill the queue all at once */
1214	for (i = 0; i < 10 && dev->rxq.qlen < RX_QLEN(dev); i++) {
1215		urb = usb_alloc_urb(0, flags);
1216		if (urb != NULL) {
1217			ret = rx_submit(dev, urb, flags);
1218			if (ret)
1219				goto err;
1220		} else {
1221			ret = -ENOMEM;
1222			goto err;
1223		}
1224	}
1225err:
1226	return ret;
1227}
1228
1229/*-------------------------------------------------------------------------*/
1230
1231// tasklet (work deferred from completions, in_irq) or timer
1232
1233static void usbnet_bh (unsigned long param)
1234{
1235	struct usbnet		*dev = (struct usbnet *) param;
1236	struct sk_buff		*skb;
1237	struct skb_data		*entry;
1238
1239	while ((skb = skb_dequeue (&dev->done))) {
1240		entry = (struct skb_data *) skb->cb;
1241		switch (entry->state) {
1242		case rx_done:
1243			entry->state = rx_cleanup;
1244			rx_process (dev, skb);
1245			continue;
1246		case tx_done:
1247		case rx_cleanup:
1248			usb_free_urb (entry->urb);
1249			dev_kfree_skb (skb);
1250			continue;
1251		default:
1252			netdev_dbg(dev->net, "bogus skb state %d\n", entry->state);
1253		}
1254	}
1255
1256	// waiting for all pending urbs to complete?
1257	if (dev->wait) {
1258		if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) {
1259			wake_up (dev->wait);
1260		}
1261
1262	// or are we maybe short a few urbs?
1263	} else if (netif_running (dev->net) &&
1264		   netif_device_present (dev->net) &&
1265		   !timer_pending (&dev->delay) &&
1266		   !test_bit (EVENT_RX_HALT, &dev->flags)) {
1267		int	temp = dev->rxq.qlen;
 
1268
1269		if (temp < RX_QLEN(dev)) {
1270			if (rx_alloc_submit(dev, GFP_ATOMIC) == -ENOLINK)
1271				return;
 
 
 
 
 
 
 
 
 
 
1272			if (temp != dev->rxq.qlen)
1273				netif_dbg(dev, link, dev->net,
1274					  "rxqlen %d --> %d\n",
1275					  temp, dev->rxq.qlen);
1276			if (dev->rxq.qlen < RX_QLEN(dev))
1277				tasklet_schedule (&dev->bh);
1278		}
1279		if (dev->txq.qlen < TX_QLEN (dev))
1280			netif_wake_queue (dev->net);
1281	}
1282}
1283
1284
1285/*-------------------------------------------------------------------------
1286 *
1287 * USB Device Driver support
1288 *
1289 *-------------------------------------------------------------------------*/
1290
1291// precondition: never called in_interrupt
1292
1293void usbnet_disconnect (struct usb_interface *intf)
1294{
1295	struct usbnet		*dev;
1296	struct usb_device	*xdev;
1297	struct net_device	*net;
1298
1299	dev = usb_get_intfdata(intf);
1300	usb_set_intfdata(intf, NULL);
1301	if (!dev)
1302		return;
1303
1304	xdev = interface_to_usbdev (intf);
1305
1306	netif_info(dev, probe, dev->net, "unregister '%s' usb-%s-%s, %s\n",
1307		   intf->dev.driver->name,
1308		   xdev->bus->bus_name, xdev->devpath,
1309		   dev->driver_info->description);
1310
1311	net = dev->net;
1312	unregister_netdev (net);
1313
1314	cancel_work_sync(&dev->kevent);
1315
1316	if (dev->driver_info->unbind)
1317		dev->driver_info->unbind (dev, intf);
1318
1319	usb_kill_urb(dev->interrupt);
1320	usb_free_urb(dev->interrupt);
1321
1322	free_netdev(net);
1323	usb_put_dev (xdev);
1324}
1325EXPORT_SYMBOL_GPL(usbnet_disconnect);
1326
1327static const struct net_device_ops usbnet_netdev_ops = {
1328	.ndo_open		= usbnet_open,
1329	.ndo_stop		= usbnet_stop,
1330	.ndo_start_xmit		= usbnet_start_xmit,
1331	.ndo_tx_timeout		= usbnet_tx_timeout,
1332	.ndo_change_mtu		= usbnet_change_mtu,
1333	.ndo_set_mac_address 	= eth_mac_addr,
1334	.ndo_validate_addr	= eth_validate_addr,
1335};
1336
1337/*-------------------------------------------------------------------------*/
1338
1339// precondition: never called in_interrupt
1340
1341static struct device_type wlan_type = {
1342	.name	= "wlan",
1343};
1344
1345static struct device_type wwan_type = {
1346	.name	= "wwan",
1347};
1348
1349int
1350usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
1351{
1352	struct usbnet			*dev;
1353	struct net_device		*net;
1354	struct usb_host_interface	*interface;
1355	struct driver_info		*info;
1356	struct usb_device		*xdev;
1357	int				status;
1358	const char			*name;
1359	struct usb_driver 	*driver = to_usb_driver(udev->dev.driver);
1360
1361	/* usbnet already took usb runtime pm, so have to enable the feature
1362	 * for usb interface, otherwise usb_autopm_get_interface may return
1363	 * failure if USB_SUSPEND(RUNTIME_PM) is enabled.
1364	 */
1365	if (!driver->supports_autosuspend) {
1366		driver->supports_autosuspend = 1;
1367		pm_runtime_enable(&udev->dev);
1368	}
1369
1370	name = udev->dev.driver->name;
1371	info = (struct driver_info *) prod->driver_info;
1372	if (!info) {
1373		dev_dbg (&udev->dev, "blacklisted by %s\n", name);
1374		return -ENODEV;
1375	}
1376	xdev = interface_to_usbdev (udev);
1377	interface = udev->cur_altsetting;
1378
1379	usb_get_dev (xdev);
1380
1381	status = -ENOMEM;
1382
1383	// set up our own records
1384	net = alloc_etherdev(sizeof(*dev));
1385	if (!net)
 
1386		goto out;
 
1387
1388	/* netdev_printk() needs this so do it as early as possible */
1389	SET_NETDEV_DEV(net, &udev->dev);
1390
1391	dev = netdev_priv(net);
1392	dev->udev = xdev;
1393	dev->intf = udev;
1394	dev->driver_info = info;
1395	dev->driver_name = name;
1396	dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV
1397				| NETIF_MSG_PROBE | NETIF_MSG_LINK);
1398	skb_queue_head_init (&dev->rxq);
1399	skb_queue_head_init (&dev->txq);
1400	skb_queue_head_init (&dev->done);
1401	skb_queue_head_init(&dev->rxq_pause);
1402	dev->bh.func = usbnet_bh;
1403	dev->bh.data = (unsigned long) dev;
1404	INIT_WORK (&dev->kevent, kevent);
1405	init_usb_anchor(&dev->deferred);
1406	dev->delay.function = usbnet_bh;
1407	dev->delay.data = (unsigned long) dev;
1408	init_timer (&dev->delay);
1409	mutex_init (&dev->phy_mutex);
1410
1411	dev->net = net;
1412	strcpy (net->name, "usb%d");
1413	memcpy (net->dev_addr, node_id, sizeof node_id);
1414
1415	/* rx and tx sides can use different message sizes;
1416	 * bind() should set rx_urb_size in that case.
1417	 */
1418	dev->hard_mtu = net->mtu + net->hard_header_len;
1419#if 0
1420// dma_supported() is deeply broken on almost all architectures
1421	// possible with some EHCI controllers
1422	if (dma_supported (&udev->dev, DMA_BIT_MASK(64)))
1423		net->features |= NETIF_F_HIGHDMA;
1424#endif
1425
1426	net->netdev_ops = &usbnet_netdev_ops;
1427	net->watchdog_timeo = TX_TIMEOUT_JIFFIES;
1428	net->ethtool_ops = &usbnet_ethtool_ops;
1429
1430	// allow device-specific bind/init procedures
1431	// NOTE net->name still not usable ...
1432	if (info->bind) {
1433		status = info->bind (dev, udev);
1434		if (status < 0)
1435			goto out1;
1436
1437		// heuristic:  "usb%d" for links we know are two-host,
1438		// else "eth%d" when there's reasonable doubt.  userspace
1439		// can rename the link if it knows better.
1440		if ((dev->driver_info->flags & FLAG_ETHER) != 0 &&
1441		    ((dev->driver_info->flags & FLAG_POINTTOPOINT) == 0 ||
1442		     (net->dev_addr [0] & 0x02) == 0))
1443			strcpy (net->name, "eth%d");
1444		/* WLAN devices should always be named "wlan%d" */
1445		if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1446			strcpy(net->name, "wlan%d");
1447		/* WWAN devices should always be named "wwan%d" */
1448		if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1449			strcpy(net->name, "wwan%d");
1450
1451		/* maybe the remote can't receive an Ethernet MTU */
1452		if (net->mtu > (dev->hard_mtu - net->hard_header_len))
1453			net->mtu = dev->hard_mtu - net->hard_header_len;
1454	} else if (!info->in || !info->out)
1455		status = usbnet_get_endpoints (dev, udev);
1456	else {
1457		dev->in = usb_rcvbulkpipe (xdev, info->in);
1458		dev->out = usb_sndbulkpipe (xdev, info->out);
1459		if (!(info->flags & FLAG_NO_SETINT))
1460			status = usb_set_interface (xdev,
1461				interface->desc.bInterfaceNumber,
1462				interface->desc.bAlternateSetting);
1463		else
1464			status = 0;
1465
1466	}
1467	if (status >= 0 && dev->status)
1468		status = init_status (dev, udev);
1469	if (status < 0)
1470		goto out3;
1471
1472	if (!dev->rx_urb_size)
1473		dev->rx_urb_size = dev->hard_mtu;
1474	dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
1475
1476	if ((dev->driver_info->flags & FLAG_WLAN) != 0)
1477		SET_NETDEV_DEVTYPE(net, &wlan_type);
1478	if ((dev->driver_info->flags & FLAG_WWAN) != 0)
1479		SET_NETDEV_DEVTYPE(net, &wwan_type);
1480
1481	status = register_netdev (net);
1482	if (status)
1483		goto out4;
1484	netif_info(dev, probe, dev->net,
1485		   "register '%s' at usb-%s-%s, %s, %pM\n",
1486		   udev->dev.driver->name,
1487		   xdev->bus->bus_name, xdev->devpath,
1488		   dev->driver_info->description,
1489		   net->dev_addr);
1490
1491	// ok, it's ready to go.
1492	usb_set_intfdata (udev, dev);
1493
1494	netif_device_attach (net);
1495
1496	if (dev->driver_info->flags & FLAG_LINK_INTR)
1497		netif_carrier_off(net);
1498
1499	return 0;
1500
1501out4:
1502	usb_free_urb(dev->interrupt);
1503out3:
1504	if (info->unbind)
1505		info->unbind (dev, udev);
1506out1:
1507	free_netdev(net);
1508out:
1509	usb_put_dev(xdev);
1510	return status;
1511}
1512EXPORT_SYMBOL_GPL(usbnet_probe);
1513
1514/*-------------------------------------------------------------------------*/
1515
1516/*
1517 * suspend the whole driver as soon as the first interface is suspended
1518 * resume only when the last interface is resumed
1519 */
1520
1521int usbnet_suspend (struct usb_interface *intf, pm_message_t message)
1522{
1523	struct usbnet		*dev = usb_get_intfdata(intf);
1524
1525	if (!dev->suspend_count++) {
1526		spin_lock_irq(&dev->txq.lock);
1527		/* don't autosuspend while transmitting */
1528		if (dev->txq.qlen && PMSG_IS_AUTO(message)) {
1529			dev->suspend_count--;
1530			spin_unlock_irq(&dev->txq.lock);
1531			return -EBUSY;
1532		} else {
1533			set_bit(EVENT_DEV_ASLEEP, &dev->flags);
1534			spin_unlock_irq(&dev->txq.lock);
1535		}
1536		/*
1537		 * accelerate emptying of the rx and queues, to avoid
1538		 * having everything error out.
1539		 */
1540		netif_device_detach (dev->net);
1541		usbnet_terminate_urbs(dev);
1542		usb_kill_urb(dev->interrupt);
1543
1544		/*
1545		 * reattach so runtime management can use and
1546		 * wake the device
1547		 */
1548		netif_device_attach (dev->net);
1549	}
1550	return 0;
1551}
1552EXPORT_SYMBOL_GPL(usbnet_suspend);
1553
1554int usbnet_resume (struct usb_interface *intf)
1555{
1556	struct usbnet		*dev = usb_get_intfdata(intf);
1557	struct sk_buff          *skb;
1558	struct urb              *res;
1559	int                     retval;
1560
1561	if (!--dev->suspend_count) {
1562		/* resume interrupt URBs */
1563		if (dev->interrupt && test_bit(EVENT_DEV_OPEN, &dev->flags))
1564			usb_submit_urb(dev->interrupt, GFP_NOIO);
1565
1566		spin_lock_irq(&dev->txq.lock);
1567		while ((res = usb_get_from_anchor(&dev->deferred))) {
1568
1569			skb = (struct sk_buff *)res->context;
1570			retval = usb_submit_urb(res, GFP_ATOMIC);
1571			if (retval < 0) {
1572				dev_kfree_skb_any(skb);
1573				usb_free_urb(res);
1574				usb_autopm_put_interface_async(dev->intf);
1575			} else {
1576				dev->net->trans_start = jiffies;
1577				__skb_queue_tail(&dev->txq, skb);
1578			}
1579		}
1580
1581		smp_mb();
1582		clear_bit(EVENT_DEV_ASLEEP, &dev->flags);
1583		spin_unlock_irq(&dev->txq.lock);
1584
1585		if (test_bit(EVENT_DEV_OPEN, &dev->flags)) {
1586			/* handle remote wakeup ASAP */
1587			if (!dev->wait &&
1588				netif_device_present(dev->net) &&
1589				!timer_pending(&dev->delay) &&
1590				!test_bit(EVENT_RX_HALT, &dev->flags))
1591					rx_alloc_submit(dev, GFP_NOIO);
1592
1593			if (!(dev->txq.qlen >= TX_QLEN(dev)))
1594				netif_tx_wake_all_queues(dev->net);
1595			tasklet_schedule (&dev->bh);
1596		}
1597	}
1598	return 0;
1599}
1600EXPORT_SYMBOL_GPL(usbnet_resume);
1601
1602
1603/*-------------------------------------------------------------------------*/
1604
1605static int __init usbnet_init(void)
1606{
1607	/* Compiler should optimize this out. */
1608	BUILD_BUG_ON(
1609		FIELD_SIZEOF(struct sk_buff, cb) < sizeof(struct skb_data));
1610
1611	random_ether_addr(node_id);
1612	return 0;
1613}
1614module_init(usbnet_init);
1615
1616static void __exit usbnet_exit(void)
1617{
1618}
1619module_exit(usbnet_exit);
1620
1621MODULE_AUTHOR("David Brownell");
1622MODULE_DESCRIPTION("USB network driver framework");
1623MODULE_LICENSE("GPL");