diff options
Diffstat (limited to 'drivers/net/usb/usbnet.c')
| -rw-r--r-- | drivers/net/usb/usbnet.c | 1309 |
1 files changed, 1309 insertions, 0 deletions
diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c new file mode 100644 index 00000000000..5b16d9a1269 --- /dev/null +++ b/drivers/net/usb/usbnet.c @@ -0,0 +1,1309 @@ +/* + * USB Network driver infrastructure + * Copyright (C) 2000-2005 by David Brownell + * Copyright (C) 2003-2005 David Hollis <dhollis@davehollis.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +/* + * This is a generic "USB networking" framework that works with several + * kinds of full and high speed networking devices: host-to-host cables, + * smart usb peripherals, and actual Ethernet adapters. + * + * These devices usually differ in terms of control protocols (if they + * even have one!) and sometimes they define new framing to wrap or batch + * Ethernet packets. Otherwise, they talk to USB pretty much the same, + * so interface (un)binding, endpoint I/O queues, fault handling, and other + * issues can usefully be addressed by this framework. + */ + +// #define DEBUG // error path messages, extra info +// #define VERBOSE // more; success messages + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/ethtool.h> +#include <linux/workqueue.h> +#include <linux/mii.h> +#include <linux/usb.h> + +#include "usbnet.h" + +#define DRIVER_VERSION "22-Aug-2005" + + +/*-------------------------------------------------------------------------*/ + +/* + * Nineteen USB 1.1 max size bulk transactions per frame (ms), max. + * Several dozen bytes of IPv4 data can fit in two such transactions. + * One maximum size Ethernet packet takes twenty four of them. + * For high speed, each frame comfortably fits almost 36 max size + * Ethernet packets (so queues should be bigger). + * + * REVISIT qlens should be members of 'struct usbnet'; the goal is to + * let the USB host controller be busy for 5msec or more before an irq + * is required, under load. Jumbograms change the equation. + */ +#define RX_MAX_QUEUE_MEMORY (60 * 1518) +#define RX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \ + (RX_MAX_QUEUE_MEMORY/(dev)->rx_urb_size) : 4) +#define TX_QLEN(dev) (((dev)->udev->speed == USB_SPEED_HIGH) ? \ + (RX_MAX_QUEUE_MEMORY/(dev)->hard_mtu) : 4) + +// reawaken network queue this soon after stopping; else watchdog barks +#define TX_TIMEOUT_JIFFIES (5*HZ) + +// throttle rx/tx briefly after some faults, so khubd might disconnect() +// us (it polls at HZ/4 usually) before we report too many false errors. +#define THROTTLE_JIFFIES (HZ/8) + +// between wakeups +#define UNLINK_TIMEOUT_MS 3 + +/*-------------------------------------------------------------------------*/ + +// randomly generated ethernet address +static u8 node_id [ETH_ALEN]; + +static const char driver_name [] = "usbnet"; + +/* use ethtool to change the level for any given device */ +static int msg_level = -1; +module_param (msg_level, int, 0); +MODULE_PARM_DESC (msg_level, "Override default message level"); + +/*-------------------------------------------------------------------------*/ + +/* handles CDC Ethernet and many other network "bulk data" interfaces */ +int usbnet_get_endpoints(struct usbnet *dev, struct usb_interface *intf) +{ + int tmp; + struct usb_host_interface *alt = NULL; + struct usb_host_endpoint *in = NULL, *out = NULL; + struct usb_host_endpoint *status = NULL; + + for (tmp = 0; tmp < intf->num_altsetting; tmp++) { + unsigned ep; + + in = out = status = NULL; + alt = intf->altsetting + tmp; + + /* take the first altsetting with in-bulk + out-bulk; + * remember any status endpoint, just in case; + * ignore other endpoints and altsetttings. + */ + for (ep = 0; ep < alt->desc.bNumEndpoints; ep++) { + struct usb_host_endpoint *e; + int intr = 0; + + e = alt->endpoint + ep; + switch (e->desc.bmAttributes) { + case USB_ENDPOINT_XFER_INT: + if (!usb_endpoint_dir_in(&e->desc)) + continue; + intr = 1; + /* FALLTHROUGH */ + case USB_ENDPOINT_XFER_BULK: + break; + default: + continue; + } + if (usb_endpoint_dir_in(&e->desc)) { + if (!intr && !in) + in = e; + else if (intr && !status) + status = e; + } else { + if (!out) + out = e; + } + } + if (in && out) + break; + } + if (!alt || !in || !out) + return -EINVAL; + + if (alt->desc.bAlternateSetting != 0 + || !(dev->driver_info->flags & FLAG_NO_SETINT)) { + tmp = usb_set_interface (dev->udev, alt->desc.bInterfaceNumber, + alt->desc.bAlternateSetting); + if (tmp < 0) + return tmp; + } + + dev->in = usb_rcvbulkpipe (dev->udev, + in->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK); + dev->out = usb_sndbulkpipe (dev->udev, + out->desc.bEndpointAddress & USB_ENDPOINT_NUMBER_MASK); + dev->status = status; + return 0; +} +EXPORT_SYMBOL_GPL(usbnet_get_endpoints); + +static void intr_complete (struct urb *urb); + +static int init_status (struct usbnet *dev, struct usb_interface *intf) +{ + char *buf = NULL; + unsigned pipe = 0; + unsigned maxp; + unsigned period; + + if (!dev->driver_info->status) + return 0; + + pipe = usb_rcvintpipe (dev->udev, + dev->status->desc.bEndpointAddress + & USB_ENDPOINT_NUMBER_MASK); + maxp = usb_maxpacket (dev->udev, pipe, 0); + + /* avoid 1 msec chatter: min 8 msec poll rate */ + period = max ((int) dev->status->desc.bInterval, + (dev->udev->speed == USB_SPEED_HIGH) ? 7 : 3); + + buf = kmalloc (maxp, GFP_KERNEL); + if (buf) { + dev->interrupt = usb_alloc_urb (0, GFP_KERNEL); + if (!dev->interrupt) { + kfree (buf); + return -ENOMEM; + } else { + usb_fill_int_urb(dev->interrupt, dev->udev, pipe, + buf, maxp, intr_complete, dev, period); + dev_dbg(&intf->dev, + "status ep%din, %d bytes period %d\n", + usb_pipeendpoint(pipe), maxp, period); + } + } + return 0; +} + +/* Passes this packet up the stack, updating its accounting. + * Some link protocols batch packets, so their rx_fixup paths + * can return clones as well as just modify the original skb. + */ +void usbnet_skb_return (struct usbnet *dev, struct sk_buff *skb) +{ + int status; + + skb->protocol = eth_type_trans (skb, dev->net); + dev->stats.rx_packets++; + dev->stats.rx_bytes += skb->len; + + if (netif_msg_rx_status (dev)) + devdbg (dev, "< rx, len %zu, type 0x%x", + skb->len + sizeof (struct ethhdr), skb->protocol); + memset (skb->cb, 0, sizeof (struct skb_data)); + status = netif_rx (skb); + if (status != NET_RX_SUCCESS && netif_msg_rx_err (dev)) + devdbg (dev, "netif_rx status %d", status); +} +EXPORT_SYMBOL_GPL(usbnet_skb_return); + + +/*------------------------------------------------------------------------- + * + * Network Device Driver (peer link to "Host Device", from USB host) + * + *-------------------------------------------------------------------------*/ + +static int usbnet_change_mtu (struct net_device *net, int new_mtu) +{ + struct usbnet *dev = netdev_priv(net); + int ll_mtu = new_mtu + net->hard_header_len; + int old_hard_mtu = dev->hard_mtu; + int old_rx_urb_size = dev->rx_urb_size; + + if (new_mtu <= 0) + return -EINVAL; + // no second zero-length packet read wanted after mtu-sized packets + if ((ll_mtu % dev->maxpacket) == 0) + return -EDOM; + net->mtu = new_mtu; + + dev->hard_mtu = net->mtu + net->hard_header_len; + if (dev->rx_urb_size == old_hard_mtu) { + dev->rx_urb_size = dev->hard_mtu; + if (dev->rx_urb_size > old_rx_urb_size) + usbnet_unlink_rx_urbs(dev); + } + + return 0; +} + +/*-------------------------------------------------------------------------*/ + +static struct net_device_stats *usbnet_get_stats (struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + return &dev->stats; +} + +/*-------------------------------------------------------------------------*/ + +/* some LK 2.4 HCDs oopsed if we freed or resubmitted urbs from + * completion callbacks. 2.5 should have fixed those bugs... + */ + +static void defer_bh(struct usbnet *dev, struct sk_buff *skb, struct sk_buff_head *list) +{ + unsigned long flags; + + spin_lock_irqsave(&list->lock, flags); + __skb_unlink(skb, list); + spin_unlock(&list->lock); + spin_lock(&dev->done.lock); + __skb_queue_tail(&dev->done, skb); + if (dev->done.qlen == 1) + tasklet_schedule(&dev->bh); + spin_unlock_irqrestore(&dev->done.lock, flags); +} + +/* some work can't be done in tasklets, so we use keventd + * + * NOTE: annoying asymmetry: if it's active, schedule_work() fails, + * but tasklet_schedule() doesn't. hope the failure is rare. + */ +void usbnet_defer_kevent (struct usbnet *dev, int work) +{ + set_bit (work, &dev->flags); + if (!schedule_work (&dev->kevent)) + deverr (dev, "kevent %d may have been dropped", work); + else + devdbg (dev, "kevent %d scheduled", work); +} +EXPORT_SYMBOL_GPL(usbnet_defer_kevent); + +/*-------------------------------------------------------------------------*/ + +static void rx_complete (struct urb *urb); + +static void rx_submit (struct usbnet *dev, struct urb *urb, gfp_t flags) +{ + struct sk_buff *skb; + struct skb_data *entry; + int retval = 0; + unsigned long lockflags; + size_t size = dev->rx_urb_size; + + if ((skb = alloc_skb (size + NET_IP_ALIGN, flags)) == NULL) { + if (netif_msg_rx_err (dev)) + devdbg (dev, "no rx skb"); + usbnet_defer_kevent (dev, EVENT_RX_MEMORY); + usb_free_urb (urb); + return; + } + skb_reserve (skb, NET_IP_ALIGN); + + entry = (struct skb_data *) skb->cb; + entry->urb = urb; + entry->dev = dev; + entry->state = rx_start; + entry->length = 0; + + usb_fill_bulk_urb (urb, dev->udev, dev->in, + skb->data, size, rx_complete, skb); + + spin_lock_irqsave (&dev->rxq.lock, lockflags); + + if (netif_running (dev->net) + && netif_device_present (dev->net) + && !test_bit (EVENT_RX_HALT, &dev->flags)) { + switch (retval = usb_submit_urb (urb, GFP_ATOMIC)){ + case -EPIPE: + usbnet_defer_kevent (dev, EVENT_RX_HALT); + break; + case -ENOMEM: + usbnet_defer_kevent (dev, EVENT_RX_MEMORY); + break; + case -ENODEV: + if (netif_msg_ifdown (dev)) + devdbg (dev, "device gone"); + netif_device_detach (dev->net); + break; + default: + if (netif_msg_rx_err (dev)) + devdbg (dev, "rx submit, %d", retval); + tasklet_schedule (&dev->bh); + break; + case 0: + __skb_queue_tail (&dev->rxq, skb); + } + } else { + if (netif_msg_ifdown (dev)) + devdbg (dev, "rx: stopped"); + retval = -ENOLINK; + } + spin_unlock_irqrestore (&dev->rxq.lock, lockflags); + if (retval) { + dev_kfree_skb_any (skb); + usb_free_urb (urb); + } +} + + +/*-------------------------------------------------------------------------*/ + +static inline void rx_process (struct usbnet *dev, struct sk_buff *skb) +{ + if (dev->driver_info->rx_fixup + && !dev->driver_info->rx_fixup (dev, skb)) + goto error; + // else network stack removes extra byte if we forced a short packet + + if (skb->len) + usbnet_skb_return (dev, skb); + else { + if (netif_msg_rx_err (dev)) + devdbg (dev, "drop"); +error: + dev->stats.rx_errors++; + skb_queue_tail (&dev->done, skb); + } +} + +/*-------------------------------------------------------------------------*/ + +static void rx_complete (struct urb *urb) +{ + struct sk_buff *skb = (struct sk_buff *) urb->context; + struct skb_data *entry = (struct skb_data *) skb->cb; + struct usbnet *dev = entry->dev; + int urb_status = urb->status; + + skb_put (skb, urb->actual_length); + entry->state = rx_done; + entry->urb = NULL; + + switch (urb_status) { + // success + case 0: + if (skb->len < dev->net->hard_header_len) { + entry->state = rx_cleanup; + dev->stats.rx_errors++; + dev->stats.rx_length_errors++; + if (netif_msg_rx_err (dev)) + devdbg (dev, "rx length %d", skb->len); + } + break; + + // stalls need manual reset. this is rare ... except that + // when going through USB 2.0 TTs, unplug appears this way. + // we avoid the highspeed version of the ETIMEOUT/EILSEQ + // storm, recovering as needed. + case -EPIPE: + dev->stats.rx_errors++; + usbnet_defer_kevent (dev, EVENT_RX_HALT); + // FALLTHROUGH + + // software-driven interface shutdown + case -ECONNRESET: // async unlink + case -ESHUTDOWN: // hardware gone + if (netif_msg_ifdown (dev)) + devdbg (dev, "rx shutdown, code %d", urb_status); + goto block; + + // we get controller i/o faults during khubd disconnect() delays. + // throttle down resubmits, to avoid log floods; just temporarily, + // so we still recover when the fault isn't a khubd delay. + case -EPROTO: + case -ETIME: + case -EILSEQ: + dev->stats.rx_errors++; + if (!timer_pending (&dev->delay)) { + mod_timer (&dev->delay, jiffies + THROTTLE_JIFFIES); + if (netif_msg_link (dev)) + devdbg (dev, "rx throttle %d", urb_status); + } +block: + entry->state = rx_cleanup; + entry->urb = urb; + urb = NULL; + break; + + // data overrun ... flush fifo? + case -EOVERFLOW: + dev->stats.rx_over_errors++; + // FALLTHROUGH + + default: + entry->state = rx_cleanup; + dev->stats.rx_errors++; + if (netif_msg_rx_err (dev)) + devdbg (dev, "rx status %d", urb_status); + break; + } + + defer_bh(dev, skb, &dev->rxq); + + if (urb) { + if (netif_running (dev->net) + && !test_bit (EVENT_RX_HALT, &dev->flags)) { + rx_submit (dev, urb, GFP_ATOMIC); + return; + } + usb_free_urb (urb); + } + if (netif_msg_rx_err (dev)) + devdbg (dev, "no read resubmitted"); +} + +static void intr_complete (struct urb *urb) +{ + struct usbnet *dev = urb->context; + int status = urb->status; + + switch (status) { + /* success */ + case 0: + dev->driver_info->status(dev, urb); + break; + + /* software-driven interface shutdown */ + case -ENOENT: // urb killed + case -ESHUTDOWN: // hardware gone + if (netif_msg_ifdown (dev)) + devdbg (dev, "intr shutdown, code %d", status); + return; + + /* NOTE: not throttling like RX/TX, since this endpoint + * already polls infrequently + */ + default: + devdbg (dev, "intr status %d", status); + break; + } + + if (!netif_running (dev->net)) + return; + + memset(urb->transfer_buffer, 0, urb->transfer_buffer_length); + status = usb_submit_urb (urb, GFP_ATOMIC); + if (status != 0 && netif_msg_timer (dev)) + deverr(dev, "intr resubmit --> %d", status); +} + +/*-------------------------------------------------------------------------*/ + +// unlink pending rx/tx; completion handlers do all other cleanup + +static int unlink_urbs (struct usbnet *dev, struct sk_buff_head *q) +{ + unsigned long flags; + struct sk_buff *skb, *skbnext; + int count = 0; + + spin_lock_irqsave (&q->lock, flags); + for (skb = q->next; skb != (struct sk_buff *) q; skb = skbnext) { + struct skb_data *entry; + struct urb *urb; + int retval; + + entry = (struct skb_data *) skb->cb; + urb = entry->urb; + skbnext = skb->next; + + // during some PM-driven resume scenarios, + // these (async) unlinks complete immediately + retval = usb_unlink_urb (urb); + if (retval != -EINPROGRESS && retval != 0) + devdbg (dev, "unlink urb err, %d", retval); + else + count++; + } + spin_unlock_irqrestore (&q->lock, flags); + return count; +} + +// Flush all pending rx urbs +// minidrivers may need to do this when the MTU changes + +void usbnet_unlink_rx_urbs(struct usbnet *dev) +{ + if (netif_running(dev->net)) { + (void) unlink_urbs (dev, &dev->rxq); + tasklet_schedule(&dev->bh); + } +} +EXPORT_SYMBOL_GPL(usbnet_unlink_rx_urbs); + +/*-------------------------------------------------------------------------*/ + +// precondition: never called in_interrupt + +static int usbnet_stop (struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + int temp; + DECLARE_WAIT_QUEUE_HEAD_ONSTACK (unlink_wakeup); + DECLARE_WAITQUEUE (wait, current); + + netif_stop_queue (net); + + if (netif_msg_ifdown (dev)) + devinfo (dev, "stop stats: rx/tx %ld/%ld, errs %ld/%ld", + dev->stats.rx_packets, dev->stats.tx_packets, + dev->stats.rx_errors, dev->stats.tx_errors + ); + + // ensure there are no more active urbs + add_wait_queue (&unlink_wakeup, &wait); + dev->wait = &unlink_wakeup; + temp = unlink_urbs (dev, &dev->txq) + unlink_urbs (dev, &dev->rxq); + + // maybe wait for deletions to finish. + while (!skb_queue_empty(&dev->rxq) && + !skb_queue_empty(&dev->txq) && + !skb_queue_empty(&dev->done)) { + msleep(UNLINK_TIMEOUT_MS); + if (netif_msg_ifdown (dev)) + devdbg (dev, "waited for %d urb completions", temp); + } + dev->wait = NULL; + remove_wait_queue (&unlink_wakeup, &wait); + + usb_kill_urb(dev->interrupt); + + /* deferred work (task, timer, softirq) must also stop. + * can't flush_scheduled_work() until we drop rtnl (later), + * else workers could deadlock; so make workers a NOP. + */ + dev->flags = 0; + del_timer_sync (&dev->delay); + tasklet_kill (&dev->bh); + + return 0; +} + +/*-------------------------------------------------------------------------*/ + +// posts reads, and enables write queuing + +// precondition: never called in_interrupt + +static int usbnet_open (struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + int retval = 0; + struct driver_info *info = dev->driver_info; + + // put into "known safe" state + if (info->reset && (retval = info->reset (dev)) < 0) { + if (netif_msg_ifup (dev)) + devinfo (dev, + "open reset fail (%d) usbnet usb-%s-%s, %s", + retval, + dev->udev->bus->bus_name, dev->udev->devpath, + info->description); + goto done; + } + + // insist peer be connected + if (info->check_connect && (retval = info->check_connect (dev)) < 0) { + if (netif_msg_ifup (dev)) + devdbg (dev, "can't open; %d", retval); + goto done; + } + + /* start any status interrupt transfer */ + if (dev->interrupt) { + retval = usb_submit_urb (dev->interrupt, GFP_KERNEL); + if (retval < 0) { + if (netif_msg_ifup (dev)) + deverr (dev, "intr submit %d", retval); + goto done; + } + } + + netif_start_queue (net); + if (netif_msg_ifup (dev)) { + char *framing; + + if (dev->driver_info->flags & FLAG_FRAMING_NC) + framing = "NetChip"; + else if (dev->driver_info->flags & FLAG_FRAMING_GL) + framing = "GeneSys"; + else if (dev->driver_info->flags & FLAG_FRAMING_Z) + framing = "Zaurus"; + else if (dev->driver_info->flags & FLAG_FRAMING_RN) + framing = "RNDIS"; + else if (dev->driver_info->flags & FLAG_FRAMING_AX) + framing = "ASIX"; + else + framing = "simple"; + + devinfo (dev, "open: enable queueing " + "(rx %d, tx %d) mtu %d %s framing", + (int)RX_QLEN (dev), (int)TX_QLEN (dev), dev->net->mtu, + framing); + } + + // delay posting reads until we're fully open + tasklet_schedule (&dev->bh); +done: + return retval; +} + +/*-------------------------------------------------------------------------*/ + +/* ethtool methods; minidrivers may need to add some more, but + * they'll probably want to use this base set. + */ + +#if defined(CONFIG_MII) || defined(CONFIG_MII_MODULE) +#define HAVE_MII + +int usbnet_get_settings (struct net_device *net, struct ethtool_cmd *cmd) +{ + struct usbnet *dev = netdev_priv(net); + + if (!dev->mii.mdio_read) + return -EOPNOTSUPP; + + return mii_ethtool_gset(&dev->mii, cmd); +} +EXPORT_SYMBOL_GPL(usbnet_get_settings); + +int usbnet_set_settings (struct net_device *net, struct ethtool_cmd *cmd) +{ + struct usbnet *dev = netdev_priv(net); + int retval; + + if (!dev->mii.mdio_write) + return -EOPNOTSUPP; + + retval = mii_ethtool_sset(&dev->mii, cmd); + + /* link speed/duplex might have changed */ + if (dev->driver_info->link_reset) + dev->driver_info->link_reset(dev); + + return retval; + +} +EXPORT_SYMBOL_GPL(usbnet_set_settings); + +u32 usbnet_get_link (struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + + /* If a check_connect is defined, return its result */ + if (dev->driver_info->check_connect) + return dev->driver_info->check_connect (dev) == 0; + + /* if the device has mii operations, use those */ + if (dev->mii.mdio_read) + return mii_link_ok(&dev->mii); + + /* Otherwise, say we're up (to avoid breaking scripts) */ + return 1; +} +EXPORT_SYMBOL_GPL(usbnet_get_link); + +int usbnet_nway_reset(struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + + if (!dev->mii.mdio_write) + return -EOPNOTSUPP; + + return mii_nway_restart(&dev->mii); +} +EXPORT_SYMBOL_GPL(usbnet_nway_reset); + +#endif /* HAVE_MII */ + +void usbnet_get_drvinfo (struct net_device *net, struct ethtool_drvinfo *info) +{ + struct usbnet *dev = netdev_priv(net); + + strncpy (info->driver, dev->driver_name, sizeof info->driver); + strncpy (info->version, DRIVER_VERSION, sizeof info->version); + strncpy (info->fw_version, dev->driver_info->description, + sizeof info->fw_version); + usb_make_path (dev->udev, info->bus_info, sizeof info->bus_info); +} +EXPORT_SYMBOL_GPL(usbnet_get_drvinfo); + +u32 usbnet_get_msglevel (struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + + return dev->msg_enable; +} +EXPORT_SYMBOL_GPL(usbnet_get_msglevel); + +void usbnet_set_msglevel (struct net_device *net, u32 level) +{ + struct usbnet *dev = netdev_priv(net); + + dev->msg_enable = level; +} +EXPORT_SYMBOL_GPL(usbnet_set_msglevel); + +/* drivers may override default ethtool_ops in their bind() routine */ +static struct ethtool_ops usbnet_ethtool_ops = { +#ifdef HAVE_MII + .get_settings = usbnet_get_settings, + .set_settings = usbnet_set_settings, + .get_link = usbnet_get_link, + .nway_reset = usbnet_nway_reset, +#endif + .get_drvinfo = usbnet_get_drvinfo, + .get_msglevel = usbnet_get_msglevel, + .set_msglevel = usbnet_set_msglevel, +}; + +/*-------------------------------------------------------------------------*/ + +/* work that cannot be done in interrupt context uses keventd. + * + * NOTE: with 2.5 we could do more of this using completion callbacks, + * especially now that control transfers can be queued. + */ +static void +kevent (struct work_struct *work) +{ + struct usbnet *dev = + container_of(work, struct usbnet, kevent); + int status; + + /* usb_clear_halt() needs a thread context */ + if (test_bit (EVENT_TX_HALT, &dev->flags)) { + unlink_urbs (dev, &dev->txq); + status = usb_clear_halt (dev->udev, dev->out); + if (status < 0 + && status != -EPIPE + && status != -ESHUTDOWN) { + if (netif_msg_tx_err (dev)) + deverr (dev, "can't clear tx halt, status %d", + status); + } else { + clear_bit (EVENT_TX_HALT, &dev->flags); + if (status != -ESHUTDOWN) + netif_wake_queue (dev->net); + } + } + if (test_bit (EVENT_RX_HALT, &dev->flags)) { + unlink_urbs (dev, &dev->rxq); + status = usb_clear_halt (dev->udev, dev->in); + if (status < 0 + && status != -EPIPE + && status != -ESHUTDOWN) { + if (netif_msg_rx_err (dev)) + deverr (dev, "can't clear rx halt, status %d", + status); + } else { + clear_bit (EVENT_RX_HALT, &dev->flags); + tasklet_schedule (&dev->bh); + } + } + + /* tasklet could resubmit itself forever if memory is tight */ + if (test_bit (EVENT_RX_MEMORY, &dev->flags)) { + struct urb *urb = NULL; + + if (netif_running (dev->net)) + urb = usb_alloc_urb (0, GFP_KERNEL); + else + clear_bit (EVENT_RX_MEMORY, &dev->flags); + if (urb != NULL) { + clear_bit (EVENT_RX_MEMORY, &dev->flags); + rx_submit (dev, urb, GFP_KERNEL); + tasklet_schedule (&dev->bh); + } + } + + if (test_bit (EVENT_LINK_RESET, &dev->flags)) { + struct driver_info *info = dev->driver_info; + int retval = 0; + + clear_bit (EVENT_LINK_RESET, &dev->flags); + if(info->link_reset && (retval = info->link_reset(dev)) < 0) { + devinfo(dev, "link reset failed (%d) usbnet usb-%s-%s, %s", + retval, + dev->udev->bus->bus_name, dev->udev->devpath, + info->description); + } + } + + if (dev->flags) + devdbg (dev, "kevent done, flags = 0x%lx", + dev->flags); +} + +/*-------------------------------------------------------------------------*/ + +static void tx_complete (struct urb *urb) +{ + struct sk_buff *skb = (struct sk_buff *) urb->context; + struct skb_data *entry = (struct skb_data *) skb->cb; + struct usbnet *dev = entry->dev; + + if (urb->status == 0) { + dev->stats.tx_packets++; + dev->stats.tx_bytes += entry->length; + } else { + dev->stats.tx_errors++; + + switch (urb->status) { + case -EPIPE: + usbnet_defer_kevent (dev, EVENT_TX_HALT); + break; + + /* software-driven interface shutdown */ + case -ECONNRESET: // async unlink + case -ESHUTDOWN: // hardware gone + break; + + // like rx, tx gets controller i/o faults during khubd delays + // and so it uses the same throttling mechanism. + case -EPROTO: + case -ETIME: + case -EILSEQ: + if (!timer_pending (&dev->delay)) { + mod_timer (&dev->delay, + jiffies + THROTTLE_JIFFIES); + if (netif_msg_link (dev)) + devdbg (dev, "tx throttle %d", + urb->status); + } + netif_stop_queue (dev->net); + break; + default: + if (netif_msg_tx_err (dev)) + devdbg (dev, "tx err %d", entry->urb->status); + break; + } + } + + urb->dev = NULL; + entry->state = tx_done; + defer_bh(dev, skb, &dev->txq); +} + +/*-------------------------------------------------------------------------*/ + +static void usbnet_tx_timeout (struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + + unlink_urbs (dev, &dev->txq); + tasklet_schedule (&dev->bh); + + // FIXME: device recovery -- reset? +} + +/*-------------------------------------------------------------------------*/ + +static int usbnet_start_xmit (struct sk_buff *skb, struct net_device *net) +{ + struct usbnet *dev = netdev_priv(net); + int length; + int retval = NET_XMIT_SUCCESS; + struct urb *urb = NULL; + struct skb_data *entry; + struct driver_info *info = dev->driver_info; + unsigned long flags; + + // some devices want funky USB-level framing, for + // win32 driver (usually) and/or hardware quirks + if (info->tx_fixup) { + skb = info->tx_fixup (dev, skb, GFP_ATOMIC); + if (!skb) { + if (netif_msg_tx_err (dev)) + devdbg (dev, "can't tx_fixup skb"); + goto drop; + } + } + length = skb->len; + + if (!(urb = usb_alloc_urb (0, GFP_ATOMIC))) { + if (netif_msg_tx_err (dev)) + devdbg (dev, "no urb"); + goto drop; + } + + entry = (struct skb_data *) skb->cb; + entry->urb = urb; + entry->dev = dev; + entry->state = tx_start; + entry->length = length; + + usb_fill_bulk_urb (urb, dev->udev, dev->out, + skb->data, skb->len, tx_complete, skb); + + /* don't assume the hardware handles USB_ZERO_PACKET + * NOTE: strictly conforming cdc-ether devices should expect + * the ZLP here, but ignore the one-byte packet. + * + * FIXME zero that byte, if it doesn't require a new skb. + */ + if ((length % dev->maxpacket) == 0) + urb->transfer_buffer_length++; + + spin_lock_irqsave (&dev->txq.lock, flags); + + switch ((retval = usb_submit_urb (urb, GFP_ATOMIC))) { + case -EPIPE: + netif_stop_queue (net); + usbnet_defer_kevent (dev, EVENT_TX_HALT); + break; + default: + if (netif_msg_tx_err (dev)) + devdbg (dev, "tx: submit urb err %d", retval); + break; + case 0: + net->trans_start = jiffies; + __skb_queue_tail (&dev->txq, skb); + if (dev->txq.qlen >= TX_QLEN (dev)) + netif_stop_queue (net); + } + spin_unlock_irqrestore (&dev->txq.lock, flags); + + if (retval) { + if (netif_msg_tx_err (dev)) + devdbg (dev, "drop, code %d", retval); +drop: + retval = NET_XMIT_SUCCESS; + dev->stats.tx_dropped++; + if (skb) + dev_kfree_skb_any (skb); + usb_free_urb (urb); + } else if (netif_msg_tx_queued (dev)) { + devdbg (dev, "> tx, len %d, type 0x%x", + length, skb->protocol); + } + return retval; +} + + +/*-------------------------------------------------------------------------*/ + +// tasklet (work deferred from completions, in_irq) or timer + +static void usbnet_bh (unsigned long param) +{ + struct usbnet *dev = (struct usbnet *) param; + struct sk_buff *skb; + struct skb_data *entry; + + while ((skb = skb_dequeue (&dev->done))) { + entry = (struct skb_data *) skb->cb; + switch (entry->state) { + case rx_done: + entry->state = rx_cleanup; + rx_process (dev, skb); + continue; + case tx_done: + case rx_cleanup: + usb_free_urb (entry->urb); + dev_kfree_skb (skb); + continue; + default: + devdbg (dev, "bogus skb state %d", entry->state); + } + } + + // waiting for all pending urbs to complete? + if (dev->wait) { + if ((dev->txq.qlen + dev->rxq.qlen + dev->done.qlen) == 0) { + wake_up (dev->wait); + } + + // or are we maybe short a few urbs? + } else if (netif_running (dev->net) + && netif_device_present (dev->net) + && !timer_pending (&dev->delay) + && !test_bit (EVENT_RX_HALT, &dev->flags)) { + int temp = dev->rxq.qlen; + int qlen = RX_QLEN (dev); + + if (temp < qlen) { + struct urb *urb; + int i; + + // don't refill the queue all at once + for (i = 0; i < 10 && dev->rxq.qlen < qlen; i++) { + urb = usb_alloc_urb (0, GFP_ATOMIC); + if (urb != NULL) + rx_submit (dev, urb, GFP_ATOMIC); + } + if (temp != dev->rxq.qlen && netif_msg_link (dev)) + devdbg (dev, "rxqlen %d --> %d", + temp, dev->rxq.qlen); + if (dev->rxq.qlen < qlen) + tasklet_schedule (&dev->bh); + } + if (dev->txq.qlen < TX_QLEN (dev)) + netif_wake_queue (dev->net); + } +} + + + +/*------------------------------------------------------------------------- + * + * USB Device Driver support + * + *-------------------------------------------------------------------------*/ + +// precondition: never called in_interrupt + +void usbnet_disconnect (struct usb_interface *intf) +{ + struct usbnet *dev; + struct usb_device *xdev; + struct net_device *net; + + dev = usb_get_intfdata(intf); + usb_set_intfdata(intf, NULL); + if (!dev) + return; + + xdev = interface_to_usbdev (intf); + + if (netif_msg_probe (dev)) + devinfo (dev, "unregister '%s' usb-%s-%s, %s", + intf->dev.driver->name, + xdev->bus->bus_name, xdev->devpath, + dev->driver_info->description); + + net = dev->net; + unregister_netdev (net); + + /* we don't hold rtnl here ... */ + flush_scheduled_work (); + + if (dev->driver_info->unbind) + dev->driver_info->unbind (dev, intf); + + free_netdev(net); + usb_put_dev (xdev); +} +EXPORT_SYMBOL_GPL(usbnet_disconnect); + + +/*-------------------------------------------------------------------------*/ + +// precondition: never called in_interrupt + +int +usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod) +{ + struct usbnet *dev; + struct net_device *net; + struct usb_host_interface *interface; + struct driver_info *info; + struct usb_device *xdev; + int status; + const char *name; + + name = udev->dev.driver->name; + info = (struct driver_info *) prod->driver_info; + if (!info) { + dev_dbg (&udev->dev, "blacklisted by %s\n", name); + return -ENODEV; + } + xdev = interface_to_usbdev (udev); + interface = udev->cur_altsetting; + + usb_get_dev (xdev); + + status = -ENOMEM; + + // set up our own records + net = alloc_etherdev(sizeof(*dev)); + if (!net) { + dbg ("can't kmalloc dev"); + goto out; + } + + dev = netdev_priv(net); + dev->udev = xdev; + dev->driver_info = info; + dev->driver_name = name; + dev->msg_enable = netif_msg_init (msg_level, NETIF_MSG_DRV + | NETIF_MSG_PROBE | NETIF_MSG_LINK); + skb_queue_head_init (&dev->rxq); + skb_queue_head_init (&dev->txq); + skb_queue_head_init (&dev->done); + dev->bh.func = usbnet_bh; + dev->bh.data = (unsigned long) dev; + INIT_WORK (&dev->kevent, kevent); + dev->delay.function = usbnet_bh; + dev->delay.data = (unsigned long) dev; + init_timer (&dev->delay); + mutex_init (&dev->phy_mutex); + + SET_MODULE_OWNER (net); + dev->net = net; + strcpy (net->name, "usb%d"); + memcpy (net->dev_addr, node_id, sizeof node_id); + + /* rx and tx sides can use different message sizes; + * bind() should set rx_urb_size in that case. + */ + dev->hard_mtu = net->mtu + net->hard_header_len; +#if 0 +// dma_supported() is deeply broken on almost all architectures + // possible with some EHCI controllers + if (dma_supported (&udev->dev, DMA_64BIT_MASK)) + net->features |= NETIF_F_HIGHDMA; +#endif + + net->change_mtu = usbnet_change_mtu; + net->get_stats = usbnet_get_stats; + net->hard_start_xmit = usbnet_start_xmit; + net->open = usbnet_open; + net->stop = usbnet_stop; + net->watchdog_timeo = TX_TIMEOUT_JIFFIES; + net->tx_timeout = usbnet_tx_timeout; + net->ethtool_ops = &usbnet_ethtool_ops; + + // allow device-specific bind/init procedures + // NOTE net->name still not usable ... + if (info->bind) { + status = info->bind (dev, udev); + if (status < 0) + goto out1; + + // heuristic: "usb%d" for links we know are two-host, + // else "eth%d" when there's reasonable doubt. userspace + // can rename the link if it knows better. + if ((dev->driver_info->flags & FLAG_ETHER) != 0 + && (net->dev_addr [0] & 0x02) == 0) + strcpy (net->name, "eth%d"); + + /* maybe the remote can't receive an Ethernet MTU */ + if (net->mtu > (dev->hard_mtu - net->hard_header_len)) + net->mtu = dev->hard_mtu - net->hard_header_len; + } else if (!info->in || !info->out) + status = usbnet_get_endpoints (dev, udev); + else { + dev->in = usb_rcvbulkpipe (xdev, info->in); + dev->out = usb_sndbulkpipe (xdev, info->out); + if (!(info->flags & FLAG_NO_SETINT)) + status = usb_set_interface (xdev, + interface->desc.bInterfaceNumber, + interface->desc.bAlternateSetting); + else + status = 0; + + } + if (status == 0 && dev->status) + status = init_status (dev, udev); + if (status < 0) + goto out3; + + if (!dev->rx_urb_size) + dev->rx_urb_size = dev->hard_mtu; + dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1); + + SET_NETDEV_DEV(net, &udev->dev); + status = register_netdev (net); + if (status) + goto out3; + if (netif_msg_probe (dev)) + devinfo (dev, "register '%s' at usb-%s-%s, %s, " + "%02x:%02x:%02x:%02x:%02x:%02x", + udev->dev.driver->name, + xdev->bus->bus_name, xdev->devpath, + dev->driver_info->description, + net->dev_addr [0], net->dev_addr [1], + net->dev_addr [2], net->dev_addr [3], + net->dev_addr [4], net->dev_addr [5]); + + // ok, it's ready to go. + usb_set_intfdata (udev, dev); + + // start as if the link is up + netif_device_attach (net); + + return 0; + +out3: + if (info->unbind) + info->unbind (dev, udev); +out1: + free_netdev(net); +out: + usb_put_dev(xdev); + return status; +} +EXPORT_SYMBOL_GPL(usbnet_probe); + +/*-------------------------------------------------------------------------*/ + +/* + * suspend the whole driver as soon as the first interface is suspended + * resume only when the last interface is resumed + */ + +int usbnet_suspend (struct usb_interface *intf, pm_message_t message) +{ + struct usbnet *dev = usb_get_intfdata(intf); + + if (!dev->suspend_count++) { + /* accelerate emptying of the rx and queues, to avoid + * having everything error out. + */ + netif_device_detach (dev->net); + (void) unlink_urbs (dev, &dev->rxq); + (void) unlink_urbs (dev, &dev->txq); + } + return 0; +} +EXPORT_SYMBOL_GPL(usbnet_suspend); + +int usbnet_resume (struct usb_interface *intf) +{ + struct usbnet *dev = usb_get_intfdata(intf); + + if (!--dev->suspend_count) { + netif_device_attach (dev->net); + tasklet_schedule (&dev->bh); + } + return 0; +} +EXPORT_SYMBOL_GPL(usbnet_resume); + + +/*-------------------------------------------------------------------------*/ + +static int __init usbnet_init(void) +{ + /* compiler should optimize this out */ + BUILD_BUG_ON (sizeof (((struct sk_buff *)0)->cb) + < sizeof (struct skb_data)); + + random_ether_addr(node_id); + return 0; +} +module_init(usbnet_init); + +static void __exit usbnet_exit(void) +{ +} +module_exit(usbnet_exit); + +MODULE_AUTHOR("David Brownell"); +MODULE_DESCRIPTION("USB network driver framework"); +MODULE_LICENSE("GPL"); |