ipxe/src/drivers/net/prism2.c

/**************************************************************************
Etherboot -  BOOTP/TFTP Bootstrap Program
Prism2 NIC driver for Etherboot

Written by Michael Brown of Fen Systems Ltd
$Id$
***************************************************************************/

/*
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

FILE_LICENCE ( GPL2_OR_LATER );

#include <etherboot.h>
#include <nic.h>
#include <ipxe/pci.h>
#include <ipxe/ethernet.h>

/*
 * Hard-coded SSID
 * Leave blank in order to connect to any available SSID
 */

static const char hardcoded_ssid[] = "";

/*
 * Maximum number of info packets to wait for on a join attempt.
 * Some APs (including the Linksys WAP11) will send a "you are disconnected" packet
 * before sending the "you are connected" packet, if the card has previously been
 * attached to the AP.
 *
 * 2 is probably a sensible value, but YMMV.
 */

#define MAX_JOIN_INFO_COUNT 2

/*
 * Type of Prism2 interface to support
 * If not already defined, select PLX
 */
#ifndef WLAN_HOSTIF
#define WLAN_HOSTIF WLAN_PLX
#endif

/*
 * Include wlan_compat, p80211 and hfa384x header files from Linux Prism2 driver
 * We need to hack some defines in order to avoid compiling kernel-specific routines
 */

#define __LINUX_WLAN__
#undef __KERNEL__
#define __I386__
#include "wlan_compat.h"
#include "p80211hdr.h"
#include "hfa384x.h"
#define BAP_TIMEOUT ( 5000 )

/*
 * A few hacks to make the coding environment more Linux-like.  This makes it somewhat
 * quicker to convert code from the Linux Prism2 driver.
 */
#include <errno.h>
#define __le16_to_cpu(x) (x)
#define __le32_to_cpu(x) (x)
#define __cpu_to_le16(x) (x)
#define __cpu_to_le32(x) (x)

#define hfa384x2host_16(n)	(__le16_to_cpu((uint16_t)(n)))
#define hfa384x2host_32(n)	(__le32_to_cpu((uint32_t)(n)))
#define host2hfa384x_16(n)	(__cpu_to_le16((uint16_t)(n)))
#define host2hfa384x_32(n)	(__cpu_to_le32((uint32_t)(n)))

/*
 * PLX9052 PCI register offsets
 * Taken from PLX9052 datasheet available from http://www.plxtech.com/download/9052/databook/9052db-20.pdf
 */

#define PLX_LOCAL_CONFIG_REGISTER_BASE ( PCI_BASE_ADDRESS_1 )
#define PLX_LOCAL_ADDRESS_SPACE_0_BASE ( PCI_BASE_ADDRESS_2 )
#define PLX_LOCAL_ADDRESS_SPACE_1_BASE ( PCI_BASE_ADDRESS_3 )
#define PLX_LOCAL_ADDRESS_SPACE_2_BASE ( PCI_BASE_ADDRESS_4 )
#define PLX_LOCAL_ADDRESS_SPACE_3_BASE ( PCI_BASE_ADDRESS_5 )

#define PRISM2_PLX_ATTR_MEM_BASE       ( PLX_LOCAL_ADDRESS_SPACE_0_BASE )
#define PRISM2_PLX_IO_BASE             ( PLX_LOCAL_ADDRESS_SPACE_1_BASE )

#define PRISM2_PCI_MEM_BASE            ( PCI_BASE_ADDRESS_0 )

/*
 * PCMCIA CIS types
 * Taken from cistpl.h in pcmcia-cs
 */

#define CISTPL_VERS_1           ( 0x15 )
#define CISTPL_END              ( 0xff )

#define CIS_STEP                ( 2 )
#define CISTPL_HEADER_LEN       ( 2 * CIS_STEP )
#define CISTPL_LEN_OFF          ( 1 * CIS_STEP )
#define CISTPL_VERS_1_STR_OFF   ( 4 * CIS_STEP )

/*
 * Prism2 constants
 * Taken from prism2sta.c in linux-wlan-ng
 */

#define COR_OFFSET      ( 0x3e0 )   /* COR attribute offset of Prism2 PC card */
#define COR_VALUE       ( 0x41 )    /* Enable PC card with irq in level trigger (but interrupts disabled) */

/* NIC specific static variables */

/* The hfa384x_t structure is used extensively in the Linux driver but is ifdef'd out in our include since __KERNEL__ is not defined.
 * This is a dummy version that contains only the fields we are interested in.
 */

typedef struct hfa384x
{
  uint32_t iobase;
  void *membase;
  uint16_t lastcmd;
  uint16_t status;         /* in host order */
  uint16_t resp0;          /* in host order */
  uint16_t resp1;          /* in host order */
  uint16_t resp2;          /* in host order */
  uint8_t  bssid[WLAN_BSSID_LEN];
} hfa384x_t;

/* The global instance of the hardware (i.e. where we store iobase and membase, in the absence of anywhere better to put them */
static hfa384x_t hw_global;

/*
 * 802.11 headers in addition to those in hfa384x_tx_frame_t (LLC and SNAP)
 * Taken from p80211conv.h
 */

typedef struct wlan_llc
{
  uint8_t   dsap;
  uint8_t   ssap;
  uint8_t   ctl;
}  wlan_llc_t;

static const wlan_llc_t wlan_llc_snap = { 0xaa, 0xaa, 0x03 }; /* LLC header indicating SNAP (?) */

#define WLAN_IEEE_OUI_LEN 3
typedef struct wlan_snap
{
  uint8_t   oui[WLAN_IEEE_OUI_LEN];
  uint16_t  type;
} wlan_snap_t;

typedef struct wlan_80211hdr
{
  wlan_llc_t llc;
  wlan_snap_t snap;
} wlan_80211hdr_t;

/*
 * Function prototypes
 */

/*
 * Hardware-level hfa384x functions
 * These are based on the ones in hfa384x.h (which are ifdef'd out since __KERNEL__ is not defined).
 * Basically, these functions are the result of hand-evaluating all the ifdefs and defines in the hfa384x.h versions.
 */

/* Retrieve the value of one of the MAC registers. */
static inline uint16_t hfa384x_getreg( hfa384x_t *hw, unsigned int reg )
{
#if (WLAN_HOSTIF == WLAN_PLX)
  return inw ( hw->iobase + reg );
#elif (WLAN_HOSTIF == WLAN_PCI)
  return readw ( hw->membase + reg );
#endif
}

/* Set the value of one of the MAC registers. */
static inline void hfa384x_setreg( hfa384x_t *hw, uint16_t val, unsigned int reg )
{
#if (WLAN_HOSTIF == WLAN_PLX)
  outw ( val, hw->iobase + reg );
#elif (WLAN_HOSTIF == WLAN_PCI)
  writew ( val, hw->membase + reg );
#endif
  return;
}

/*
 * Noswap versions
 * Etherboot is i386 only, so swap and noswap are the same...
 */
static inline uint16_t hfa384x_getreg_noswap( hfa384x_t *hw, unsigned int reg )
{
  return hfa384x_getreg ( hw, reg );
}
static inline void hfa384x_setreg_noswap( hfa384x_t *hw, uint16_t val, unsigned int reg )
{
  hfa384x_setreg ( hw, val, reg );
}

/*
 * Low-level hfa384x functions
 * These are based on the ones in hfa384x.c, modified to work in the Etherboot environment.
 */

/*
 * hfa384x_docmd_wait
 *
 * Waits for availability of the Command register, then
 * issues the given command.  Then polls the Evstat register
 * waiting for command completion.
 * Arguments:
 *       hw              device structure
 *       cmd             Command in host order
 *       parm0           Parameter0 in host order
 *       parm1           Parameter1 in host order
 *       parm2           Parameter2 in host order
 * Returns:
 *       0               success
 *       >0              command indicated error, Status and Resp0-2 are
 *                       in hw structure.
 */
static int hfa384x_docmd_wait( hfa384x_t *hw, uint16_t cmd, uint16_t parm0, uint16_t parm1, uint16_t parm2)
{
  uint16_t reg = 0;
  uint16_t counter = 0;

  /* wait for the busy bit to clear */
  counter = 0;
  reg = hfa384x_getreg(hw, HFA384x_CMD);
  while ( HFA384x_CMD_ISBUSY(reg) && (counter < 10) ) {
    reg = hfa384x_getreg(hw, HFA384x_CMD);
    counter++;
    udelay(10);
  }
  if (HFA384x_CMD_ISBUSY(reg)) {
    printf("hfa384x_cmd timeout(1), reg=0x%0hx.\n", reg);
    return -ETIMEDOUT;
  }

  /* busy bit clear, write command */
  hfa384x_setreg(hw, parm0, HFA384x_PARAM0);
  hfa384x_setreg(hw, parm1, HFA384x_PARAM1);
  hfa384x_setreg(hw, parm2, HFA384x_PARAM2);
  hw->lastcmd = cmd;
  hfa384x_setreg(hw, cmd, HFA384x_CMD);

  /* Now wait for completion */
  counter = 0;
  reg = hfa384x_getreg(hw, HFA384x_EVSTAT);
  /* Initialization is the problem.  It takes about
     100ms. "normal" commands are typically is about
     200-400 us (I've never seen less than 200).  Longer
     is better so that we're not hammering the bus. */
  while ( !HFA384x_EVSTAT_ISCMD(reg) && (counter < 5000)) {
    reg = hfa384x_getreg(hw, HFA384x_EVSTAT);
    counter++;
    udelay(200);
  }
  if ( ! HFA384x_EVSTAT_ISCMD(reg) ) {
    printf("hfa384x_cmd timeout(2), reg=0x%0hx.\n", reg);
    return -ETIMEDOUT;
  }

  /* Read status and response */
  hw->status = hfa384x_getreg(hw, HFA384x_STATUS);
  hw->resp0 = hfa384x_getreg(hw, HFA384x_RESP0);
  hw->resp1 = hfa384x_getreg(hw, HFA384x_RESP1);
  hw->resp2 = hfa384x_getreg(hw, HFA384x_RESP2);
  hfa384x_setreg(hw, HFA384x_EVACK_CMD, HFA384x_EVACK);
  return HFA384x_STATUS_RESULT_GET(hw->status);
}

/*
 * Prepare BAP for access.  Assigns FID and RID, sets offset register
 * and waits for BAP to become available.
 *
 * Arguments:
 *	hw		device structure
 *	id		FID or RID, destined for the select register (host order)
 *	offset		An _even_ offset into the buffer for the given FID/RID.
 * Returns:
 *	0		success
 */
static int hfa384x_prepare_bap(hfa384x_t *hw, uint16_t id, uint16_t offset)
{
  int result = 0;
  uint16_t reg;
  uint16_t i;

  /* Validate offset, buf, and len */
  if ( (offset > HFA384x_BAP_OFFSET_MAX) || (offset % 2) ) {
    result = -EINVAL;
  } else {
    /* Write fid/rid and offset */
    hfa384x_setreg(hw, id, HFA384x_SELECT0);
    udelay(10);
    hfa384x_setreg(hw, offset, HFA384x_OFFSET0);
    /* Wait for offset[busy] to clear (see BAP_TIMEOUT) */
    i = 0;
    do {
      reg = hfa384x_getreg(hw, HFA384x_OFFSET0);
      if ( i > 0 ) udelay(2);
      i++;
    } while ( i < BAP_TIMEOUT && HFA384x_OFFSET_ISBUSY(reg));
    if ( i >= BAP_TIMEOUT ) {
      /* failure */
      result = reg;
    } else if ( HFA384x_OFFSET_ISERR(reg) ){
      /* failure */
      result = reg;
    }
  }
  return result;
}

/*
 * Copy data from BAP to memory.
 *
 * Arguments:
 *	hw		device structure
 *	id		FID or RID, destined for the select register (host order)
 *	offset		An _even_ offset into the buffer for the given FID/RID.
 *	buf		ptr to array of bytes
 *	len		length of data to transfer in bytes
 * Returns:
 *	0		success
 */
static int hfa384x_copy_from_bap(hfa384x_t *hw, uint16_t id, uint16_t offset,
			  void *buf, unsigned int len)
{
  int result = 0;
  uint8_t	*d = (uint8_t*)buf;
  uint16_t i;
  uint16_t reg = 0;

  /* Prepare BAP */
  result = hfa384x_prepare_bap ( hw, id, offset );
  if ( result == 0 ) {
    /* Read even(len) buf contents from data reg */
    for ( i = 0; i < (len & 0xfffe); i+=2 ) {
      *(uint16_t*)(&(d[i])) = hfa384x_getreg_noswap(hw, HFA384x_DATA0);
    }
    /* If len odd, handle last byte */
    if ( len % 2 ){
      reg = hfa384x_getreg_noswap(hw, HFA384x_DATA0);
      d[len-1] = ((uint8_t*)(&reg))[0];
    }
  }
  if (result) {
    printf ( "copy_from_bap(%#hx, %#hx, %d) failed, result=%#hx\n", id, offset, len, result);
  }
  return result;
}

/*
 * Copy data from memory to BAP.
 *
 * Arguments:
 *	hw		device structure
 *	id		FID or RID, destined for the select register (host order)
 *	offset		An _even_ offset into the buffer for the given FID/RID.
 *	buf		ptr to array of bytes
 *	len		length of data to transfer in bytes
 * Returns:
 *	0		success
 */
static int hfa384x_copy_to_bap(hfa384x_t *hw, uint16_t id, uint16_t offset,
			void *buf, unsigned int len)
{
  int result = 0;
  uint8_t	*d = (uint8_t*)buf;
  uint16_t i;
  uint16_t savereg;

  /* Prepare BAP */
  result = hfa384x_prepare_bap ( hw, id, offset );
  if ( result == 0 ) {
    /* Write even(len) buf contents to data reg */
    for ( i = 0; i < (len & 0xfffe); i+=2 ) {
      hfa384x_setreg_noswap(hw, *(uint16_t*)(&(d[i])), HFA384x_DATA0);
    }
    /* If len odd, handle last byte */
    if ( len % 2 ){
      savereg = hfa384x_getreg_noswap(hw, HFA384x_DATA0);
      result = hfa384x_prepare_bap ( hw, id, offset + (len & 0xfffe) );
      if ( result == 0 ) {
	((uint8_t*)(&savereg))[0] = d[len-1];
	hfa384x_setreg_noswap(hw, savereg, HFA384x_DATA0);
      }
    }
  }
  if (result) {
    printf ( "copy_to_bap(%#hx, %#hx, %d) failed, result=%#hx\n", id, offset, len, result);
  }
  return result;
}

/*
 * Request a given record to be copied to/from the record buffer.
 *
 * Arguments:
 *	hw		device structure
 *	write		[0|1] copy the record buffer to the given
 *			configuration record. (host order)
 *	rid		RID of the record to read/write. (host order)
 *
 * Returns:
 *	0		success
 */
static inline int hfa384x_cmd_access(hfa384x_t *hw, uint16_t write, uint16_t rid)
{
  return hfa384x_docmd_wait(hw, HFA384x_CMD_CMDCODE_SET(HFA384x_CMDCODE_ACCESS) | HFA384x_CMD_WRITE_SET(write), rid, 0, 0);
}

/*
 * Performs the sequence necessary to read a config/info item.
 *
 * Arguments:
 *	hw		device structure
 *	rid		config/info record id (host order)
 *	buf		host side record buffer.  Upon return it will
 *			contain the body portion of the record (minus the
 *			RID and len).
 *	len		buffer length (in bytes, should match record length)
 *
 * Returns:
 *	0		success
 */
static int hfa384x_drvr_getconfig(hfa384x_t *hw, uint16_t rid, void *buf, uint16_t len)
{
  int result = 0;
  hfa384x_rec_t	rec;

  /* Request read of RID */
  result = hfa384x_cmd_access( hw, 0, rid);
  if ( result ) {
    printf("Call to hfa384x_cmd_access failed\n");
    return -1;
  }
  /* Copy out record length */
  result = hfa384x_copy_from_bap( hw, rid, 0, &rec, sizeof(rec));
  if ( result ) {
    return -1;
  }
  /* Validate the record length */
  if ( ((hfa384x2host_16(rec.reclen)-1)*2) != len ) {  /* note body len calculation in bytes */
    printf ( "RID len mismatch, rid=%#hx hlen=%d fwlen=%d\n", rid, len, (hfa384x2host_16(rec.reclen)-1)*2);
    return -1;
  }
  /* Copy out record data */
  result = hfa384x_copy_from_bap( hw, rid, sizeof(rec), buf, len);
  return result;
}

/*
 * Performs the sequence necessary to read a 16/32 bit config/info item
 * and convert it to host order.
 *
 * Arguments:
 *	hw		device structure
 *	rid		config/info record id (in host order)
 *	val		ptr to 16/32 bit buffer to receive value (in host order)
 *
 * Returns:
 *	0		success
 */
#if 0 /* Not actually used anywhere */
static int hfa384x_drvr_getconfig16(hfa384x_t *hw, uint16_t rid, void *val)
{
  int result = 0;
  result = hfa384x_drvr_getconfig(hw, rid, val, sizeof(uint16_t));
  if ( result == 0 ) {
    *((uint16_t*)val) = hfa384x2host_16(*((uint16_t*)val));
  }
  return result;
}
#endif
#if 0 /* Not actually used anywhere */
static int hfa384x_drvr_getconfig32(hfa384x_t *hw, uint16_t rid, void *val)
{
  int result = 0;
  result = hfa384x_drvr_getconfig(hw, rid, val, sizeof(uint32_t));
  if ( result == 0 ) {
    *((uint32_t*)val) = hfa384x2host_32(*((uint32_t*)val));
  }
  return result;
}
#endif

/*
 * Performs the sequence necessary to write a config/info item.
 *
 * Arguments:
 *	hw		device structure
 *	rid		config/info record id (in host order)
 *	buf		host side record buffer
 *	len		buffer length (in bytes)
 *
 * Returns:
 *	0		success
 */
static int hfa384x_drvr_setconfig(hfa384x_t *hw, uint16_t rid, void *buf, uint16_t len)
{
  int result = 0;
  hfa384x_rec_t	rec;

  rec.rid = host2hfa384x_16(rid);
  rec.reclen = host2hfa384x_16((len/2) + 1); /* note conversion to words, +1 for rid field */
  /* write the record header */
  result = hfa384x_copy_to_bap( hw, rid, 0, &rec, sizeof(rec));
  if ( result ) {
    printf("Failure writing record header\n");
    return -1;
  }
  /* write the record data (if there is any) */
  if ( len > 0 ) {
    result = hfa384x_copy_to_bap( hw, rid, sizeof(rec), buf, len);
    if ( result ) {
      printf("Failure writing record data\n");
      return -1;
    }
  }
  /* Trigger setting of record */
  result = hfa384x_cmd_access( hw, 1, rid);
  return result;
}

/*
 * Performs the sequence necessary to write a 16/32 bit config/info item.
 *
 * Arguments:
 *	hw		device structure
 *	rid		config/info record id (in host order)
 *	val		16/32 bit value to store (in host order)
 *
 * Returns:
 *	0		success
 */
static int hfa384x_drvr_setconfig16(hfa384x_t *hw, uint16_t rid, uint16_t *val)
{
  uint16_t value;
  value = host2hfa384x_16(*val);
  return hfa384x_drvr_setconfig(hw, rid, &value, sizeof(uint16_t));
}
#if 0 /* Not actually used anywhere */
static int hfa384x_drvr_setconfig32(hfa384x_t *hw, uint16_t rid, uint32_t *val)
{
  uint32_t value;
  value = host2hfa384x_32(*val);
  return hfa384x_drvr_setconfig(hw, rid, &value, sizeof(uint32_t));
}
#endif

/*
 * Wait for an event, with specified checking interval and timeout.
 * Automatically acknolwedges events.
 *
 * Arguments:
 *	hw		device structure
 *      event_mask      EVSTAT register mask of events to wait for
 *	event_ack	EVACK register set of events to be acknowledged if they happen (can be
 *			used to acknowledge "ignorable" events in addition to the "main" event)
 *      wait            Time (in us) to wait between each poll of the register
 *      timeout         Maximum number of polls before timing out
 *      descr           Descriptive text string of what is being waited for
 *                      (will be printed out if a timeout happens)
 *
 * Returns:
 *      value of EVSTAT register, or 0 on failure
 */
static int hfa384x_wait_for_event(hfa384x_t *hw, uint16_t event_mask, uint16_t event_ack, int wait, int timeout, const char *descr)
{
  uint16_t reg;
  int count = 0;

  do {
    reg = hfa384x_getreg(hw, HFA384x_EVSTAT);
    if ( count > 0 ) udelay(wait);
    count++;
  } while ( !(reg & event_mask) && count < timeout);
  if ( count >= timeout ) {
    printf("hfa384x: Timed out waiting for %s\n", descr);
    return 0; /* Return failure */
  }
  /* Acknowledge all events that we were waiting on */
  hfa384x_setreg(hw, reg & ( event_mask | event_ack ), HFA384x_EVACK);
  return reg;
}

/**************************************************************************
POLL - Wait for a frame
***************************************************************************/
static int prism2_poll(struct nic *nic, int retrieve)
{
  uint16_t reg;
  uint16_t rxfid;
  uint16_t result;
  hfa384x_rx_frame_t rxdesc;
  hfa384x_t *hw = &hw_global;

  /* Check for received packet */
  reg = hfa384x_getreg(hw, HFA384x_EVSTAT);
  if ( ! HFA384x_EVSTAT_ISRX(reg) ) {
    /* No packet received - return 0 */
    return 0;
  }

  if ( ! retrieve ) return 1;

  /* Acknowledge RX event */
  hfa384x_setreg(hw, HFA384x_EVACK_RX_SET(1), HFA384x_EVACK);
  /* Get RX FID */
  rxfid = hfa384x_getreg(hw, HFA384x_RXFID);
  /* Get the descriptor (including headers) */
  result = hfa384x_copy_from_bap(hw, rxfid, 0, &rxdesc, sizeof(rxdesc));
  if ( result ) {
    return 0; /* fail */
  }
  /* Byte order convert once up front. */
  rxdesc.status = hfa384x2host_16(rxdesc.status);
  rxdesc.time = hfa384x2host_32(rxdesc.time);
  rxdesc.data_len = hfa384x2host_16(rxdesc.data_len);

  /* Fill in nic->packetlen */
  nic->packetlen = rxdesc.data_len;
  if ( nic->packetlen > 0 ) {
    /* Fill in nic->packet */
    /*
     * NOTE: Packets as received have an 8-byte header (LLC+SNAP(?)) terminating with the packet type.
     * Etherboot expects a 14-byte header terminating with the packet type (it ignores the rest of the
     * header), so we use a quick hack to achieve this.
     */
    result = hfa384x_copy_from_bap(hw, rxfid, HFA384x_RX_DATA_OFF,
				   nic->packet + ETH_HLEN - sizeof(wlan_80211hdr_t), nic->packetlen);
    if ( result ) {
      return 0; /* fail */
    }
  }
  return 1; /* Packet successfully received */
}

/**************************************************************************
TRANSMIT - Transmit a frame
***************************************************************************/
static void prism2_transmit(
			    struct nic *nic,
			    const char *d,			/* Destination */
			    unsigned int t,			/* Type */
			    unsigned int s,			/* size */
			    const char *p)			/* Packet */
{
  hfa384x_t *hw = &hw_global;
  hfa384x_tx_frame_t txdesc;
  wlan_80211hdr_t p80211hdr = { wlan_llc_snap, {{0,0,0},0} };
  uint16_t fid;
  uint16_t status;
  int result;

  // Request FID allocation
  result = hfa384x_docmd_wait(hw, HFA384x_CMD_CMDCODE_SET(HFA384x_CMDCODE_ALLOC), HFA384x_DRVR_TXBUF_MAX, 0, 0);
  if (result != 0) {
    printf("hfa384x: Tx FID allocate command failed: Aborting transmit..\n");
    return;
  }
  if ( !hfa384x_wait_for_event(hw, HFA384x_EVSTAT_ALLOC, HFA384x_EVACK_INFO, 10, 50, "Tx FID to be allocated\n" ) ) return;
  fid = hfa384x_getreg(hw, HFA384x_ALLOCFID);

  /* Build Tx frame structure */
  memset(&txdesc, 0, sizeof(txdesc));
  txdesc.tx_control = host2hfa384x_16( HFA384x_TX_MACPORT_SET(0) | HFA384x_TX_STRUCTYPE_SET(1) |
				       HFA384x_TX_TXEX_SET(1) | HFA384x_TX_TXOK_SET(1) );
  txdesc.frame_control =  host2ieee16( WLAN_SET_FC_FTYPE(WLAN_FTYPE_DATA) |
				       WLAN_SET_FC_FSTYPE(WLAN_FSTYPE_DATAONLY) |
				       WLAN_SET_FC_TODS(1) );
  memcpy(txdesc.address1, hw->bssid, WLAN_ADDR_LEN);
  memcpy(txdesc.address2, nic->node_addr, WLAN_ADDR_LEN);
  memcpy(txdesc.address3, d, WLAN_ADDR_LEN);
  txdesc.data_len = host2hfa384x_16( sizeof(txdesc) + sizeof(p80211hdr) + s );
  /* Set up SNAP header */
  /* Let OUI default to RFC1042 (0x000000) */
  p80211hdr.snap.type = htons(t);

  /* Copy txdesc, p80211hdr and payload parts to FID */
  result = hfa384x_copy_to_bap(hw, fid, 0, &txdesc, sizeof(txdesc));
  if ( result ) return; /* fail */
  result = hfa384x_copy_to_bap( hw, fid, sizeof(txdesc), &p80211hdr, sizeof(p80211hdr) );
  if ( result ) return; /* fail */
  result = hfa384x_copy_to_bap( hw, fid, sizeof(txdesc) + sizeof(p80211hdr), (uint8_t*)p, s );
  if ( result ) return; /* fail */

  /* Issue Tx command */
  result = hfa384x_docmd_wait(hw, HFA384x_CMD_CMDCODE_SET(HFA384x_CMDCODE_TX), fid, 0, 0);
  if ( result != 0 ) {
    printf("hfa384x: Transmit failed with result %#hx.\n", result);
    return;
  }

  /* Wait for transmit completion (or exception) */
  result = hfa384x_wait_for_event(hw, HFA384x_EVSTAT_TXEXC | HFA384x_EVSTAT_TX, HFA384x_EVACK_INFO,
				  200, 500, "Tx to complete\n" );
  if ( !result ) return; /* timeout failure */
  if ( HFA384x_EVSTAT_ISTXEXC(result) ) {
    fid = hfa384x_getreg(hw, HFA384x_TXCOMPLFID);
    printf ( "Tx exception occurred with fid %#hx\n", fid );
    result = hfa384x_copy_from_bap(hw, fid, 0, &status, sizeof(status));
    if ( result ) return; /* fail */
    printf("hfa384x: Tx error occurred (status %#hx):\n", status);
    if ( HFA384x_TXSTATUS_ISACKERR(status) ) { printf(" ...acknowledgement error\n"); }
    if ( HFA384x_TXSTATUS_ISFORMERR(status) ) { printf(" ...format error\n"); }
    if ( HFA384x_TXSTATUS_ISDISCON(status) ) { printf(" ...disconnected error\n"); }
    if ( HFA384x_TXSTATUS_ISAGEDERR(status) ) { printf(" ...AGED error\n"); }
    if ( HFA384x_TXSTATUS_ISRETRYERR(status) ) { printf(" ...retry error\n"); }
    return; /* fail */
  }
}

/**************************************************************************
DISABLE - Turn off ethernet interface
***************************************************************************/
static void prism2_disable ( struct nic *nic __unused ) {
  /* put the card in its initial state */
}

/**************************************************************************
IRQ - Enable, Disable, or Force interrupts
***************************************************************************/
static void prism2_irq(struct nic *nic __unused, irq_action_t action __unused)
{
  switch ( action ) {
  case DISABLE :
    break;
  case ENABLE :
    break;
  case FORCE :
    break;
  }
}

/**************************************************************************
Operations table
***************************************************************************/
static struct nic_operations prism2_operations = {
	.connect	= dummy_connect,
	.poll		= prism2_poll,
	.transmit	= prism2_transmit,
	.irq		= prism2_irq,
};

/**************************************************************************
PROBE - Look for an adapter, this routine's visible to the outside
You should omit the last argument struct pci_device * for a non-PCI NIC
***************************************************************************/
static int prism2_probe ( struct nic *nic, hfa384x_t *hw ) {
  int result;
  uint16_t tmp16 = 0;
  uint16_t infofid;
  hfa384x_InfFrame_t inf;
  char ssid[HFA384x_RID_CNFDESIREDSSID_LEN];
  int info_count = 0;

  nic->irqno  = 0;

  /* Initialize card */
  result = hfa384x_docmd_wait(hw, HFA384x_CMDCODE_INIT, 0,0,0); /* Send initialize command */
  if ( result ) printf ( "Initialize command returned %#hx\n", result );
  hfa384x_setreg(hw, 0, HFA384x_INTEN); /* Disable interrupts */
  hfa384x_setreg(hw, 0xffff, HFA384x_EVACK); /* Acknowledge any spurious events */

  DBG ( "MAC address %s\n", eth_ntoa ( nic->node_addr ) );

  /* Retrieve MAC address (and fill out nic->node_addr) */
  hfa384x_drvr_getconfig ( hw, HFA384x_RID_CNFOWNMACADDR, nic->node_addr, HFA384x_RID_CNFOWNMACADDR_LEN );

  /* Prepare card for autojoin */
  /* This procedure is reverse-engineered from a register-level trace of the Linux driver's join process */
  tmp16 = WLAN_DATA_MAXLEN; /* Set maximum data length */
  result = hfa384x_drvr_setconfig16(hw, HFA384x_RID_CNFMAXDATALEN, &tmp16);
  if ( result ) printf ( "Set Max Data Length command returned %#hx\n", result );
  tmp16 = 0x000f; /* Set transmit rate(?) */
  result = hfa384x_drvr_setconfig16(hw, HFA384x_RID_TXRATECNTL, &tmp16);
  if ( result ) printf ( "Set Transmit Rate command returned %#hx\n", result );
  tmp16 = HFA384x_CNFAUTHENTICATION_OPENSYSTEM; /* Set authentication type to OpenSystem */
  result = hfa384x_drvr_setconfig16(hw, HFA384x_RID_CNFAUTHENTICATION, &tmp16);
  if ( result ) printf ( "Set Authentication Type command returned %#hx\n", result );
  /* Set SSID */
  memset(ssid, 0, HFA384x_RID_CNFDESIREDSSID_LEN);
  for ( tmp16=0; tmp16<sizeof(hardcoded_ssid); tmp16++ ) { ssid[2+tmp16] = hardcoded_ssid[tmp16]; }
  ssid[0] = sizeof(hardcoded_ssid) - 1; /* Ignore terminating zero */
  result = hfa384x_drvr_setconfig(hw, HFA384x_RID_CNFDESIREDSSID, ssid, HFA384x_RID_CNFDESIREDSSID_LEN); /* Set the SSID */
  if ( result ) printf ( "Set SSID command returned %#hx\n", result );
  tmp16 = 1; /* Set port type to ESS port */
  result = hfa384x_drvr_setconfig16(hw, HFA384x_RID_CNFPORTTYPE, &tmp16);
  if ( result ) printf ( "Set port type command returned %#hx\n", result );
  /* Enable card */
  result = hfa384x_docmd_wait(hw, HFA384x_CMD_CMDCODE_SET(HFA384x_CMDCODE_ENABLE) | HFA384x_CMD_MACPORT_SET(0), 0,0,0);
  if ( result ) printf ( "Enable command returned %#hx\n", result );

  do {
    /* Increment info_count, abort if too many attempts.
     * See comment next to definition of MAX_JOIN_INFO_COUNT for explanation.
     */
    info_count++;
    if ( info_count > MAX_JOIN_INFO_COUNT ) {
      printf ( "Too many failed attempts - aborting\n" );
      return 0;
    }

    /* Wait for info frame to indicate link status */
    if ( sizeof(hardcoded_ssid) == 1 ) {
      /* Empty SSID => join to any SSID */
      printf ( "Attempting to autojoin to any available access point (attempt %d)...", info_count );
    } else {
      printf ( "Attempting to autojoin to SSID %s (attempt %d)...", &ssid[2], info_count );
    }

    if ( !hfa384x_wait_for_event(hw, HFA384x_EVSTAT_INFO, 0, 1000, 2000, "Info event" ) ) return 0;
    printf("done\n");
    infofid = hfa384x_getreg(hw, HFA384x_INFOFID);
    /* Retrieve the length */
    result = hfa384x_copy_from_bap( hw, infofid, 0, &inf.framelen, sizeof(uint16_t));
    if ( result ) return 0; /* fail */
    inf.framelen = hfa384x2host_16(inf.framelen);
    /* Retrieve the rest */
    result = hfa384x_copy_from_bap( hw, infofid, sizeof(uint16_t),
				    &(inf.infotype), inf.framelen * sizeof(uint16_t));
    if ( result ) return 0; /* fail */
    if ( inf.infotype != HFA384x_IT_LINKSTATUS ) {
      /* Not a Link Status info frame: die */
      printf ( "Unexpected info frame type %#hx (not LinkStatus type)\n", inf.infotype );
      return 0;
    }
    inf.info.linkstatus.linkstatus = hfa384x2host_16(inf.info.linkstatus.linkstatus);
    if ( inf.info.linkstatus.linkstatus != HFA384x_LINK_CONNECTED ) {
      /* Link not connected - retry */
      printf ( "Link not connected (status %#hx)\n", inf.info.linkstatus.linkstatus );
    }
  } while ( inf.info.linkstatus.linkstatus != HFA384x_LINK_CONNECTED );

  /* Retrieve BSSID and print Connected message */
  result = hfa384x_drvr_getconfig(hw, HFA384x_RID_CURRENTBSSID, hw->bssid, WLAN_BSSID_LEN);

  DBG ( "Link connected (BSSID %s - ", eth_ntoa ( hw->bssid ) );
  DBG ( " MAC address %s)\n", eth_ntoa (nic->node_addr ) );

  /* point to NIC specific routines */
  nic->nic_op	= &prism2_operations;
  return 1;
}