orinoco.c

/* orinoco.c - (formerly known as dldwd_cs.c and orinoco_cs.c)
 *
 * A driver for Hermes or Prism 2 chipset based PCMCIA wireless
 * adaptors, with Lucent/Agere, Intersil or Symbol firmware.
 *
 * Current maintainers (as of 29 September 2003) are:
 * 	Pavel Roskin <proski AT gnu.org>
 * and	David Gibson <hermes AT gibson.dropbear.id.au>
 *
 * (C) Copyright David Gibson, IBM Corporation 2001-2003.
 * Copyright (C) 2000 David Gibson, Linuxcare Australia.
 *	With some help from :
 * Copyright (C) 2001 Jean Tourrilhes, HP Labs
 * Copyright (C) 2001 Benjamin Herrenschmidt
 *
 * Based on dummy_cs.c 1.27 2000/06/12 21:27:25
 *
 * Portions based on wvlan_cs.c 1.0.6, Copyright Andreas Neuhaus <andy
 * AT fasta.fh-dortmund.de>
 *      http://www.stud.fh-dortmund.de/~andy/wvlan/
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.1 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License
 * at http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS"
 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
 * the License for the specific language governing rights and
 * limitations under the License.
 *
 * The initial developer of the original code is David A. Hinds
 * <dahinds AT users.sourceforge.net>.  Portions created by David
 * A. Hinds are Copyright (C) 1999 David A. Hinds.  All Rights
 * Reserved.
 *
 * Alternatively, the contents of this file may be used under the
 * terms of the GNU General Public License version 2 (the "GPL"), in
 * which case the provisions of the GPL are applicable instead of the
 * above.  If you wish to allow the use of your version of this file
 * only under the terms of the GPL and not to allow others to use your
 * version of this file under the MPL, indicate your decision by
 * deleting the provisions above and replace them with the notice and
 * other provisions required by the GPL.  If you do not delete the
 * provisions above, a recipient may use your version of this file
 * under either the MPL or the GPL.  */

/*
 * TODO
 *	o Handle de-encapsulation within network layer, provide 802.11
 *	  headers (patch from Thomas 'Dent' Mirlacher)
 *	o Fix possible races in SPY handling.
 *	o Disconnect wireless extensions from fundamental configuration.
 *	o (maybe) Software WEP support (patch from Stano Meduna).
 *	o (maybe) Use multiple Tx buffers - driver handling queue
 *	  rather than firmware.
 */

/* Locking and synchronization:
 *
 * The basic principle is that everything is serialized through a
 * single spinlock, priv->lock.  The lock is used in user, bh and irq
 * context, so when taken outside hardirq context it should always be
 * taken with interrupts disabled.  The lock protects both the
 * hardware and the struct orinoco_private.
 *
 * Another flag, priv->hw_unavailable indicates that the hardware is
 * unavailable for an extended period of time (e.g. suspended, or in
 * the middle of a hard reset).  This flag is protected by the
 * spinlock.  All code which touches the hardware should check the
 * flag after taking the lock, and if it is set, give up on whatever
 * they are doing and drop the lock again.  The orinoco_lock()
 * function handles this (it unlocks and returns -EBUSY if
 * hw_unavailable is non-zero).
 */

#define DRIVER_NAME "orinoco"

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/if_arp.h>
#include <linux/wireless.h>
#include <net/iw_handler.h>
#include <net/ieee80211.h>

#include "hermes_rid.h"
#include "orinoco.h"

/********************************************************************/
/* Module information                                               */
/********************************************************************/

MODULE_AUTHOR("Pavel Roskin <proski@gnu.org> & David Gibson <hermes@gibson.dropbear.id.au>");
MODULE_DESCRIPTION("Driver for Lucent Orinoco, Prism II based and similar wireless cards");
MODULE_LICENSE("Dual MPL/GPL");

/* Level of debugging. Used in the macros in orinoco.h */
#ifdef ORINOCO_DEBUG
int orinoco_debug = ORINOCO_DEBUG;
module_param(orinoco_debug, int, 0644);
MODULE_PARM_DESC(orinoco_debug, "Debug level");
EXPORT_SYMBOL(orinoco_debug);
#endif

static int suppress_linkstatus; /* = 0 */
module_param(suppress_linkstatus, bool, 0644);
MODULE_PARM_DESC(suppress_linkstatus, "Don't log link status changes");
static int ignore_disconnect; /* = 0 */
module_param(ignore_disconnect, int, 0644);
MODULE_PARM_DESC(ignore_disconnect, "Don't report lost link to the network layer");

static int force_monitor; /* = 0 */
module_param(force_monitor, int, 0644);
MODULE_PARM_DESC(force_monitor, "Allow monitor mode for all firmware versions");

/********************************************************************/
/* Compile time configuration and compatibility stuff               */
/********************************************************************/

/* We do this this way to avoid ifdefs in the actual code */
#ifdef WIRELESS_SPY
#define SPY_NUMBER(priv)	(priv->spy_data.spy_number)
#else
#define SPY_NUMBER(priv)	0
#endif /* WIRELESS_SPY */

/********************************************************************/
/* Internal constants                                               */
/********************************************************************/

/* 802.2 LLC/SNAP header used for Ethernet encapsulation over 802.11 */
static const u8 encaps_hdr[] = {0xaa, 0xaa, 0x03, 0x00, 0x00, 0x00};
#define ENCAPS_OVERHEAD		(sizeof(encaps_hdr) + 2)

#define ORINOCO_MIN_MTU		256
#define ORINOCO_MAX_MTU		(IEEE80211_DATA_LEN - ENCAPS_OVERHEAD)

#define SYMBOL_MAX_VER_LEN	(14)
#define USER_BAP		0
#define IRQ_BAP			1
#define MAX_IRQLOOPS_PER_IRQ	10
#define MAX_IRQLOOPS_PER_JIFFY	(20000/HZ) /* Based on a guestimate of
					    * how many events the
					    * device could
					    * legitimately generate */
#define SMALL_KEY_SIZE		5
#define LARGE_KEY_SIZE		13
#define TX_NICBUF_SIZE_BUG	1585		/* Bug in Symbol firmware */

#define DUMMY_FID		0xFFFF

/*#define MAX_MULTICAST(priv)	(priv->firmware_type == FIRMWARE_TYPE_AGERE ? \
  HERMES_MAX_MULTICAST : 0)*/
#define MAX_MULTICAST(priv)	(HERMES_MAX_MULTICAST)

#define ORINOCO_INTEN	 	(HERMES_EV_RX | HERMES_EV_ALLOC \
				 | HERMES_EV_TX | HERMES_EV_TXEXC \
				 | HERMES_EV_WTERR | HERMES_EV_INFO \
				 | HERMES_EV_INFDROP )

#define MAX_RID_LEN 1024

static const struct iw_handler_def orinoco_handler_def;
static const struct ethtool_ops orinoco_ethtool_ops;

/********************************************************************/
/* Data tables                                                      */
/********************************************************************/

/* The frequency of each channel in MHz */
static const long channel_frequency[] = {
	2412, 2417, 2422, 2427, 2432, 2437, 2442,
	2447, 2452, 2457, 2462, 2467, 2472, 2484
};
#define NUM_CHANNELS ARRAY_SIZE(channel_frequency)

/* This tables gives the actual meanings of the bitrate IDs returned
 * by the firmware. */
static struct {
	int bitrate; /* in 100s of kilobits */
	int automatic;
	u16 agere_txratectrl;
	u16 intersil_txratectrl;
} bitrate_table[] = {
	{110, 1,  3, 15}, /* Entry 0 is the default */
	{10,  0,  1,  1},
	{10,  1,  1,  1},
	{20,  0,  2,  2},
	{20,  1,  6,  3},
	{55,  0,  4,  4},
	{55,  1,  7,  7},
	{110, 0,  5,  8},
};
#define BITRATE_TABLE_SIZE ARRAY_SIZE(bitrate_table)

/********************************************************************/
/* Data types                                                       */
/********************************************************************/

/* Beginning of the Tx descriptor, used in TxExc handling */
struct hermes_txexc_data {
	struct hermes_tx_descriptor desc;
	__le16 frame_ctl;
	__le16 duration_id;
	u8 addr1[ETH_ALEN];
} __attribute__ ((packed));

/* Rx frame header except compatibility 802.3 header */
struct hermes_rx_descriptor {
	/* Control */
	__le16 status;
	__le32 time;
	u8 silence;
	u8 signal;
	u8 rate;
	u8 rxflow;
	__le32 reserved;

	/* 802.11 header */
	__le16 frame_ctl;
	__le16 duration_id;
	u8 addr1[ETH_ALEN];
	u8 addr2[ETH_ALEN];
	u8 addr3[ETH_ALEN];
	__le16 seq_ctl;
	u8 addr4[ETH_ALEN];

	/* Data length */
	__le16 data_len;
} __attribute__ ((packed));

/********************************************************************/
/* Function prototypes                                              */
/********************************************************************/

static int __orinoco_program_rids(struct net_device *dev);
static void __orinoco_set_multicast_list(struct net_device *dev);

/********************************************************************/
/* Internal helper functions                                        */
/********************************************************************/

static inline void set_port_type(struct orinoco_private *priv)
{
	switch (priv->iw_mode) {
	case IW_MODE_INFRA:
		priv->port_type = 1;
		priv->createibss = 0;
		break;
	case IW_MODE_ADHOC:
		if (priv->prefer_port3) {
			priv->port_type = 3;
			priv->createibss = 0;
		} else {
			priv->port_type = priv->ibss_port;
			priv->createibss = 1;
		}
		break;
	case IW_MODE_MONITOR:
		priv->port_type = 3;
		priv->createibss = 0;
		break;
	default:
		printk(KERN_ERR "%s: Invalid priv->iw_mode in set_port_type()\n",
		       priv->ndev->name);
	}
}

#define ORINOCO_MAX_BSS_COUNT	64
static int orinoco_bss_data_allocate(struct orinoco_private *priv)
{
	if (priv->bss_data)
		return 0;

	priv->bss_data =
	    kzalloc(ORINOCO_MAX_BSS_COUNT * sizeof(bss_element), GFP_KERNEL);
	if (!priv->bss_data) {
		printk(KERN_WARNING "Out of memory allocating beacons");
		return -ENOMEM;
	}
	return 0;
}

static void orinoco_bss_data_free(struct orinoco_private *priv)
{
	kfree(priv->bss_data);
	priv->bss_data = NULL;
}

static void orinoco_bss_data_init(struct orinoco_private *priv)
{
	int i;

	INIT_LIST_HEAD(&priv->bss_free_list);
	INIT_LIST_HEAD(&priv->bss_list);
	for (i = 0; i < ORINOCO_MAX_BSS_COUNT; i++)
		list_add_tail(&priv->bss_data[i].list, &priv->bss_free_list);
}

/********************************************************************/
/* Device methods                                                   */
/********************************************************************/

static int orinoco_open(struct net_device *dev)
{
	struct orinoco_private *priv = netdev_priv(dev);
	unsigned long flags;
	int err;

	if (orinoco_lock(priv, &flags) != 0)
		return -EBUSY;

	err = __orinoco_up(dev);

	if (! err)
		priv->open = 1;

	orinoco_unlock(priv, &flags);

	return err;
}

static int orinoco_stop(struct net_device *dev)
{
	struct orinoco_private *priv = netdev_priv(dev);
	int err = 0;

	/* We mustn't use orinoco_lock() here, because we need to be
	   able to close the interface even if hw_unavailable is set
	   (e.g. as we're released after a PC Card removal) */
	spin_lock_irq(&priv->lock);

	priv->open = 0;

	err = __orinoco_down(dev);

	spin_unlock_irq(&priv->lock);

	return err;
}

static struct net_device_stats *orinoco_get_stats(struct net_device *dev)
{
	struct orinoco_private *priv = netdev_priv(dev);
	
	return &priv->stats;
}

static struct iw_statistics *orinoco_get_wireless_stats(struct net_device *dev)
{
	struct orinoco_private *priv = netdev_priv(dev);
	hermes_t *hw = &priv->hw;
	struct iw_statistics *wstats = &priv->wstats;
	int err;
	unsigned long flags;

	if (! netif_device_present(dev)) {
		printk(KERN_WARNING "%s: get_wireless_stats() called while device not present\n",
		       dev->name);
		return NULL; /* FIXME: Can we do better than this? */
	}

	/* If busy, return the old stats.  Returning NULL may cause
	 * the interface to disappear from /proc/net/wireless */
	if (orinoco_lock(priv, &flags) != 0)
		return wstats;

	/* We can't really wait for the tallies inquiry command to
	 * complete, so we just use the previous results and trigger
	 * a new tallies inquiry command for next time - Jean II */
	/* FIXME: Really we should wait for the inquiry to come back -
	 * as it is the stats we give don't make a whole lot of sense.
	 * Unfortunately, it's not clear how to do that within the
	 * wireless extensions framework: I think we're in user
	 * context, but a lock seems to be held by the time we get in
	 * here so we're not safe to sleep here. */
	hermes_inquire(hw, HERMES_INQ_TALLIES);

	if (priv->iw_mode == IW_MODE_ADHOC) {
		memset(&wstats->qual, 0, sizeof(wstats->qual));
		/* If a spy address is defined, we report stats of the
		 * first spy address - Jean II */
		if (SPY_NUMBER(priv)) {
			wstats->qual.qual = priv->spy_data.spy_stat[0].qual;
			wstats->qual.level = priv->spy_data.spy_stat[0].level;
			wstats->qual.noise = priv->spy_data.spy_stat[0].noise;
			wstats->qual.updated = priv->spy_data.spy_stat[0].updated;
		}
	} else {
		struct {
			__le16 qual, signal, noise, unused;
		} __attribute__ ((packed)) cq;

		err = HERMES_READ_RECORD(hw, USER_BAP,
					 HERMES_RID_COMMSQUALITY, &cq);

		if (!err) {
			wstats->qual.qual = (int)le16_to_cpu(cq.qual);
			wstats->qual.level = (int)le16_to_cpu(cq.signal) - 0x95;
			wstats->qual.noise = (int)le16_to_cpu(cq.noise) - 0x95;
			wstats->qual.updated = 7;
		}
	}

	orinoco_unlock(priv, &flags);
	return wstats;
}

static void orinoco_set_multicast_list(struct net_device *dev)
{
	struct orinoco_private *priv = netdev_priv(dev);
	unsigned long flags;

	if (orinoco_lock(priv, &flags) != 0) {
		printk(KERN_DEBUG "%s: orinoco_set_multicast_list() "
		       "called when hw_unavailable\n", dev->name);
		return;
	}

	__orinoco_set_multicast_list(dev);
	orinoco_unlock(priv, &flags);
}

static int orinoco_change_mtu(struct net_device *dev, int new_mtu)
{
	struct orinoco_private *priv = netdev_priv(dev);

	if ( (new_mtu < ORINOCO_MIN_MTU) || (new_mtu > ORINOCO_MAX_MTU) )
		return -EINVAL;

	if ( (new_mtu + ENCAPS_OVERHEAD + IEEE80211_HLEN) >
	     (priv->nicbuf_size - ETH_HLEN) )
		return -EINVAL;

	dev->mtu = new_mtu;

	return 0;
}

/********************************************************************/
/* Tx path                                                          */
/********************************************************************/

static int orinoco_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct orinoco_private *priv = netdev_priv(dev);
	struct net_device_stats *stats = &priv->stats;
	hermes_t *hw = &priv->hw;
	int err = 0;
	u16 txfid = priv->txfid;
	struct ethhdr *eh;
	int data_off;
	struct hermes_tx_descriptor desc;
	unsigned long flags;

	if (! netif_running(dev)) {
		printk(KERN_ERR "%s: Tx on stopped device!\n",
		       dev->name);
		return NETDEV_TX_BUSY;
	}
	
	if (netif_queue_stopped(dev)) {
		printk(KERN_DEBUG "%s: Tx while transmitter busy!\n", 
		       dev->name);
		return NETDEV_TX_BUSY;
	}
	
	if (orinoco_lock(priv, &flags) != 0) {
		printk(KERN_ERR "%s: orinoco_xmit() called while hw_unavailable\n",
		       dev->name);
		return NETDEV_TX_BUSY;
	}

	if (! netif_carrier_ok(dev) || (priv->iw_mode == IW_MODE_MONITOR)) {
		/* Oops, the firmware hasn't established a connection,
                   silently drop the packet (this seems to be the
                   safest approach). */
		goto drop;
	}

	/* Check packet length */
	if (skb->len < ETH_HLEN)
		goto drop;

	eh = (struct ethhdr *)skb->data;

	memset(&desc, 0, sizeof(desc));
 	desc.tx_control = cpu_to_le16(HERMES_TXCTRL_TX_OK | HERMES_TXCTRL_TX_EX);
	err = hermes_bap_pwrite(hw, USER_BAP, &desc, sizeof(desc), txfid, 0);
	if (err) {
		if (net_ratelimit())
			printk(KERN_ERR "%s: Error %d writing Tx descriptor "
			       "to BAP\n", dev->name, err);
		goto busy;
	}

	/* Clear the 802.11 header and data length fields - some
	 * firmwares (e.g. Lucent/Agere 8.xx) appear to get confused
	 * if this isn't done. */
	hermes_clear_words(hw, HERMES_DATA0,
			   HERMES_802_3_OFFSET - HERMES_802_11_OFFSET);

	/* Encapsulate Ethernet-II frames */
	if (ntohs(eh->h_proto) > ETH_DATA_LEN) { /* Ethernet-II frame */
		struct header_struct {
			struct ethhdr eth;	/* 802.3 header */
			u8 encap[6];		/* 802.2 header */
		} __attribute__ ((packed)) hdr;

		/* Strip destination and source from the data */
		skb_pull(skb, 2 * ETH_ALEN);
		data_off = HERMES_802_2_OFFSET + sizeof(encaps_hdr);

		/* And move them to a separate header */
		memcpy(&hdr.eth, eh, 2 * ETH_ALEN);
		hdr.eth.h_proto = htons(sizeof(encaps_hdr) + skb->len);
		memcpy(hdr.encap, encaps_hdr, sizeof(encaps_hdr));

		err = hermes_bap_pwrite(hw, USER_BAP, &hdr, sizeof(hdr),
					txfid, HERMES_802_3_OFFSET);
		if (err) {
			if (net_ratelimit())
				printk(KERN_ERR "%s: Error %d writing packet "
				       "header to BAP\n", dev->name, err);
			goto busy;
		}
	} else { /* IEEE 802.3 frame */
		data_off = HERMES_802_3_OFFSET;
	}

	err = hermes_bap_pwrite(hw, USER_BAP, skb->data, skb->len,
				txfid, data_off);
	if (err) {
		printk(KERN_ERR "%s: Error %d writing packet to BAP\n",
		       dev->name, err);
		goto busy;
	}

	/* Finally, we actually initiate the send */
	netif_stop_queue(dev);

	err = hermes_docmd_wait(hw, HERMES_CMD_TX | HERMES_CMD_RECL,
				txfid, NULL);
	if (err) {
		netif_start_queue(dev);
		if (net_ratelimit())
			printk(KERN_ERR "%s: Error %d transmitting packet\n",
				dev->name, err);
		goto busy;
	}

	dev->trans_start = jiffies;
	stats->tx_bytes += data_off + skb->len;
	goto ok;

 drop:
	stats->tx_errors++;
	stats->tx_dropped++;

 ok:
	orinoco_unlock(priv, &flags);
	dev_kfree_skb(skb);
	return NETDEV_TX_OK;

 busy:
	if (err == -EIO)
		schedule_work(&priv->reset_work);
	orinoco_unlock(priv, &flags);
	return NETDEV_TX_BUSY;
}

static void __orinoco_ev_alloc(struct net_device *dev, hermes_t *hw)
{
	struct orinoco_private *priv = netdev_priv(dev);
	u16 fid = hermes_read_regn(hw, ALLOCFID);

	if (fid != priv->txfid) {
		if (fid != DUMMY_FID)
			printk(KERN_WARNING "%s: Allocate event on unexpected fid (%04X)\n",
			       dev->name, fid);
		return;
	}

	hermes_write_regn(hw, ALLOCFID, DUMMY_FID);
}

static void __orinoco_ev_tx(struct net_device *dev, hermes_t *hw)
{
	struct orinoco_private *priv = netdev_priv(dev);
	struct net_device_stats *stats = &priv->stats;

	stats->tx_packets++;

	netif_wake_queue(dev);

	hermes_write_regn(hw, TXCOMPLFID, DUMMY_FID);
}

static void __orinoco_ev_txexc(struct net_device *dev, hermes_t *hw)
{
	struct orinoco_private *priv = netdev_priv(dev);
	struct net_device_stats *stats = &priv->stats;
	u16 fid = hermes_read_regn(hw, TXCOMPLFID);
	u16 status;
	struct hermes_txexc_data hdr;
	int err = 0;

	if (fid == DUMMY_FID)
		return; /* Nothing's really happened */

	/* Read part of the frame header - we need status and addr1 */
	err = hermes_bap_pread(hw, IRQ_BAP, &hdr,
			       sizeof(struct hermes_txexc_data),
			       fid, 0);

	hermes_write_regn(hw, TXCOMPLFID, DUMMY_FID);
	stats->tx_errors++;

	if (err) {
		printk(KERN_WARNING "%s: Unable to read descriptor on Tx error "
		       "(FID=%04X error %d)\n",
		       dev->name, fid, err);
		return;
	}
	
	DEBUG(1, "%s: Tx error, err %d (FID=%04X)\n", dev->name,
	      err, fid);
    
	/* We produce a TXDROP event only for retry or lifetime
	 * exceeded, because that's the only status that really mean
	 * that this particular node went away.
	 * Other errors means that *we* screwed up. - Jean II */
	status = le16_to_cpu(hdr.desc.status);
	if (status & (HERMES_TXSTAT_RETRYERR | HERMES_TXSTAT_AGEDERR)) {
		union iwreq_data	wrqu;

		/* Copy 802.11 dest address.
		 * We use the 802.11 header because the frame may
		 * not be 802.3 or may be mangled...
		 * In Ad-Hoc mode, it will be the node address.
		 * In managed mode, it will be most likely the AP addr
		 * User space will figure out how to convert it to
		 * whatever it needs (IP address or else).
		 * - Jean II */
		memcpy(wrqu.addr.sa_data, hdr.addr1, ETH_ALEN);
		wrqu.addr.sa_family = ARPHRD_ETHER;

		/* Send event to user space */
		wireless_send_event(dev, IWEVTXDROP, &wrqu, NULL);
	}

	netif_wake_queue(dev);
}

static void orinoco_tx_timeout(struct net_device *dev)
{
	struct orinoco_private *priv = netdev_priv(dev);
	struct net_device_stats *stats = &priv->stats;
	struct hermes *hw = &priv->hw;

	printk(KERN_WARNING "%s: Tx timeout! "
	       "ALLOCFID=%04x, TXCOMPLFID=%04x, EVSTAT=%04x\n",
	       dev->name, hermes_read_regn(hw, ALLOCFID),
	       hermes_read_regn(hw, TXCOMPLFID), hermes_read_regn(hw, EVSTAT));

	stats->tx_errors++;

	schedule_work(&priv->reset_work);
}

/********************************************************************/
/* Rx path (data frames)                                            */
/********************************************************************/

/* Does the frame have a SNAP header indicating it should be
 * de-encapsulated to Ethernet-II? */
static inline int is_ethersnap(void *_hdr)
{
	u8 *hdr = _hdr;

	/* We de-encapsulate all packets which, a) have SNAP headers
	 * (i.e. SSAP=DSAP=0xaa and CTRL=0x3 in the 802.2 LLC header
	 * and where b) the OUI of the SNAP header is 00:00:00 or
	 * 00:00:f8 - we need both because different APs appear to use
	 * different OUIs for some reason */
	return (memcmp(hdr, &encaps_hdr, 5) == 0)
		&& ( (hdr[5] == 0x00) || (hdr[5] == 0xf8) );
}

static inline void orinoco_spy_gather(struct net_device *dev, u_char *mac,
				      int level, int noise)
{
	struct iw_quality wstats;
	wstats.level = level - 0x95;
	wstats.noise = noise - 0x95;
	wstats.qual = (level > noise) ? (level - noise) : 0;
	wstats.updated = 7;
	/* Update spy records */
	wireless_spy_update(dev, mac, &wstats);
}

static void orinoco_stat_gather(struct net_device *dev,
				struct sk_buff *skb,
				struct hermes_rx_descriptor *desc)
{
	struct orinoco_private *priv = netdev_priv(dev);

	/* Using spy support with lots of Rx packets, like in an
	 * infrastructure (AP), will really slow down everything, because
	 * the MAC address must be compared to each entry of the spy list.
	 * If the user really asks for it (set some address in the
	 * spy list), we do it, but he will pay the price.
	 * Note that to get here, you need both WIRELESS_SPY
	 * compiled in AND some addresses in the list !!!
	 */
	/* Note : gcc will optimise the whole section away if
	 * WIRELESS_SPY is not defined... - Jean II */
	if (SPY_NUMBER(priv)) {
		orinoco_spy_gather(dev, skb_mac_header(skb) + ETH_ALEN,
				   desc->signal, desc->silence);
	}
}

/*
 * orinoco_rx_monitor - handle received monitor frames.
 *
 * Arguments:
 *	dev		network device
 *	rxfid		received FID
 *	desc		rx descriptor of the frame
 *
 * Call context: interrupt
 */
static void orinoco_rx_monitor(struct net_device *dev, u16 rxfid,
			       struct hermes_rx_descriptor *desc)
{
	u32 hdrlen = 30;	/* return full header by default */
	u32 datalen = 0;
	u16 fc;
	int err;
	int len;
	struct sk_buff *skb;
	struct orinoco_private *priv = netdev_priv(dev);
	struct net_device_stats *stats = &priv->stats;
	hermes_t *hw = &priv->hw;

	len = le16_to_cpu(desc->data_len);

	/* Determine the size of the header and the data */
	fc = le16_to_cpu(desc->frame_ctl);
	switch (fc & IEEE80211_FCTL_FTYPE) {
	case IEEE80211_FTYPE_DATA:
		if ((fc & IEEE80211_FCTL_TODS)
		    && (fc & IEEE80211_FCTL_FROMDS))
			hdrlen = 30;
		else
			hdrlen = 24;
		datalen = len;
		break;
	case IEEE80211_FTYPE_MGMT:
		hdrlen = 24;
		datalen = len;
		break;
	case IEEE80211_FTYPE_CTL:
		switch (fc & IEEE80211_FCTL_STYPE) {
		case IEEE80211_STYPE_PSPOLL:
		case IEEE80211_STYPE_RTS:
		case IEEE80211_STYPE_CFEND:
		case IEEE80211_STYPE_CFENDACK:
			hdrlen = 16;
			break;
		case IEEE80211_STYPE_CTS:
		case IEEE80211_STYPE_ACK:
			hdrlen = 10;
			break;
		}
		break;
	default:
		/* Unknown frame type */
		break;
	}

	/* sanity check the length */
	if (datalen > IEEE80211_DATA_LEN + 12) {
		printk(KERN_DEBUG "%s: oversized monitor frame, "
		       "data length = %d\n", dev->name, datalen);
		stats->rx_length_errors++;
		goto update_stats;
	}

	skb = dev_alloc_skb(hdrlen + datalen);
	if (!skb) {
		printk(KERN_WARNING "%s: Cannot allocate skb for monitor frame\n",
		       dev->name);
		goto update_stats;
	}

	/* Copy the 802.11 header to the skb */
	memcpy(skb_put(skb, hdrlen), &(desc->frame_ctl), hdrlen);
	skb_reset_mac_header(skb);

	/* If any, copy the data from the card to the skb */
	if (datalen > 0) {
		err = hermes_bap_pread(hw, IRQ_BAP, skb_put(skb, datalen),
				       ALIGN(datalen, 2), rxfid,
				       HERMES_802_2_OFFSET);
		if (err) {
			printk(KERN_ERR "%s: error %d reading monitor frame\n",
			       dev->name, err);
			goto drop;
		}
	}

	skb->dev = dev;
	skb->ip_summed = CHECKSUM_NONE;
	skb->pkt_type = PACKET_OTHERHOST;
	skb->protocol = __constant_htons(ETH_P_802_2);
	
	dev->last_rx = jiffies;
	stats->rx_packets++;
	stats->rx_bytes += skb->len;

	netif_rx(skb);
	return;

 drop:
	dev_kfree_skb_irq(skb);
 update_stats:
	stats->rx_errors++;
	stats->rx_dropped++;
}

static void __orinoco_ev_rx(struct net_device *dev, hermes_t *hw)
{
	struct orinoco_private *priv = netdev_priv(dev);
	struct net_device_stats *stats = &priv->stats;
	struct iw_statistics *wstats = &priv->wstats;
	struct sk_buff *skb = NULL;
	u16 rxfid, status, fc;
	int length;
	struct hermes_rx_descriptor desc;
	struct ethhdr *hdr;
	int err;

	rxfid = hermes_read_regn(hw, RXFID);

	err = hermes_bap_pread(hw, IRQ_BAP, &desc, sizeof(desc),
			       rxfid, 0);
	if (err) {
		printk(KERN_ERR "%s: error %d reading Rx descriptor. "
		       "Frame dropped.\n", dev->name, err);
		goto update_stats;
	}

	status = le16_to_cpu(desc.status);

	if (status & HERMES_RXSTAT_BADCRC) {
		DEBUG(1, "%s: Bad CRC on Rx. Frame dropped.\n",
		      dev->name);
		stats->rx_crc_errors++;
		goto update_stats;
	}

	/* Handle frames in monitor mode */
	if (priv->iw_mode == IW_MODE_MONITOR) {
		orinoco_rx_monitor(dev, rxfid, &desc);
		return;
	}

	if (status & HERMES_RXSTAT_UNDECRYPTABLE) {
		DEBUG(1, "%s: Undecryptable frame on Rx. Frame dropped.\n",
		      dev->name);
		wstats->discard.code++;
		goto update_stats;
	}

	length = le16_to_cpu(desc.data_len);
	fc = le16_to_cpu(desc.frame_ctl);

	/* Sanity checks */
	if (length < 3) { /* No for even an 802.2 LLC header */
		/* At least on Symbol firmware with PCF we get quite a
                   lot of these legitimately - Poll frames with no
                   data. */
		return;
	}
	if (length > IEEE80211_DATA_LEN) {
		printk(KERN_WARNING "%s: Oversized frame received (%d bytes)\n",
		       dev->name, length);
		stats->rx_length_errors++;
		goto update_stats;
	}

	/* We need space for the packet data itself, plus an ethernet
	   header, plus 2 bytes so we can align the IP header on a
	   32bit boundary, plus 1 byte so we can read in odd length
	   packets from the card, which has an IO granularity of 16
	   bits */  
	skb = dev_alloc_skb(length+ETH_HLEN+2+1);
	if (!skb) {
		printk(KERN_WARNING "%s: Can't allocate skb for Rx\n",
		       dev->name);
		goto update_stats;
	}

	/* We'll prepend the header, so reserve space for it.  The worst
	   case is no decapsulation, when 802.3 header is prepended and
	   nothing is removed.  2 is for aligning the IP header.  */
	skb_reserve(skb, ETH_HLEN + 2);

	err = hermes_bap_pread(hw, IRQ_BAP, skb_put(skb, length),
			       ALIGN(length, 2), rxfid,
			       HERMES_802_2_OFFSET);
	if (err) {
		printk(KERN_ERR "%s: error %d reading frame. "
		       "Frame dropped.\n", dev->name, err);
		goto drop;
	}

	/* Handle decapsulation
	 * In most cases, the firmware tell us about SNAP frames.
	 * For some reason, the SNAP frames sent by LinkSys APs
	 * are not properly recognised by most firmwares.
	 * So, check ourselves */
	if (length >= ENCAPS_OVERHEAD &&
	    (((status & HERMES_RXSTAT_MSGTYPE) == HERMES_RXSTAT_1042) ||
	     ((status & HERMES_RXSTAT_MSGTYPE) == HERMES_RXSTAT_TUNNEL) ||
	     is_ethersnap(skb->data))) {
		/* These indicate a SNAP within 802.2 LLC within
		   802.11 frame which we'll need to de-encapsulate to
		   the original EthernetII frame. */
		hdr = (struct ethhdr *)skb_push(skb, ETH_HLEN - ENCAPS_OVERHEAD);
	} else {
		/* 802.3 frame - prepend 802.3 header as is */
		hdr = (struct ethhdr *)skb_push(skb, ETH_HLEN);
		hdr->h_proto = htons(length);
	}
	memcpy(hdr->h_dest, desc.addr1, ETH_ALEN);
	if (fc & IEEE80211_FCTL_FROMDS)
		memcpy(hdr->h_source, desc.addr3, ETH_ALEN);
	else
		memcpy(hdr->h_source, desc.addr2, ETH_ALEN);

	dev->last_rx = jiffies;
	skb->protocol = eth_type_trans(skb, dev);
	skb->ip_summed = CHECKSUM_NONE;
	if (fc & IEEE80211_FCTL_TODS)
		skb->pkt_type = PACKET_OTHERHOST;
	
	/* Process the wireless stats if needed */
	orinoco_stat_gather(dev, skb, &desc);

	/* Pass the packet to the networking stack */
	netif_rx(skb);
	stats->rx_packets++;
	stats->rx_bytes += length;

	return;

 drop:	
	dev_kfree_skb_irq(skb);
 update_stats:
	stats->rx_errors++;
	stats->rx_dropped++;
}

/********************************************************************/
/* Rx path (info frames)                                            */
/********************************************************************/

static void print_linkstatus(struct net_device *dev, u16 status)
{
	char * s;

	if (suppress_linkstatus)
		return;

	switch (status) {
	case HERMES_LINKSTATUS_NOT_CONNECTED:
		s = "Not Connected";
		break;
	case HERMES_LINKSTATUS_CONNECTED:
		s = "Connected";
		break;
	case HERMES_LINKSTATUS_DISCONNECTED:
		s = "Disconnected";
		break;
	case HERMES_LINKSTATUS_AP_CHANGE:
		s = "AP Changed";
		break;
	case HERMES_LINKSTATUS_AP_OUT_OF_RANGE:
		s = "AP Out of Range";
		break;
	case HERMES_LINKSTATUS_AP_IN_RANGE:
		s = "AP In Range";
		break;