drivers/qtn/wlan/if_media.c - kernel/quantenna - Git at Google

 /*
  * Copyright (c) 1997
  *	Jonathan Stone and Jason R. Thorpe.  All rights reserved.
  *
  * This software is derived from information provided by Matt Thomas.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. All advertising materials mentioning features or use of this software
  *    must display the following acknowledgement:
  *      This product includes software developed by Jonathan Stone
  *	and Jason R. Thorpe for the NetBSD Project.
  * 4. The names of the authors may not be used to endorse or promote products
  *    derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  * $Id: if_media.c 1721 2006-09-20 08:45:13Z mentor $
  */

 /*
  * BSD/OS-compatible network interface media selection.
  *
  * Where it is safe to do so, this code strays slightly from the BSD/OS
  * design.  Software which uses the API (device drivers, basically)
  * shouldn't notice any difference.
  *
  * Many thanks to Matt Thomas for providing the information necessary
  * to implement this interface.
  */

 #ifndef EXPORT_SYMTAB
 #define	EXPORT_SYMTAB
 #endif

 #ifndef AUTOCONF_INCLUDED
 #include <linux/config.h>
 #endif
 #include <linux/version.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/if.h>
 #include <linux/netdevice.h>
 #ifndef ifr_media
 #define	ifr_media	ifr_ifru.ifru_ivalue
 #endif

 #include <asm/uaccess.h>

 #include "net80211/if_media.h"

 /*
  * Compile-time options:
  * IFMEDIA_DEBUG:
  *	turn on implementation-level debug printfs.
  * 	Useful for debugging newly-ported  drivers.
  */

 struct ifmedia_entry *ifmedia_match(struct ifmedia *, int, int);

 #ifdef IFMEDIA_DEBUG
 int ifmedia_debug = 0;
 static void ifmedia_printword(int);
 #endif

 /*
  * Initialize if_media struct for a specific interface instance.
  */
 void
 ifmedia_init(struct ifmedia *ifm, int dontcare_mask,
 	ifm_change_cb_t change_callback, ifm_stat_cb_t status_callback)
 {
 	LIST_INIT(&ifm->ifm_list);
 	ifm->ifm_cur = NULL;
 	ifm->ifm_media = 0;
 	ifm->ifm_mask = dontcare_mask;		/* IF don't-care bits */
 	ifm->ifm_change = change_callback;
 	ifm->ifm_status = status_callback;
 }

 void
 ifmedia_removeall(struct ifmedia *ifm)
 {
 	struct ifmedia_entry *entry;

 	for (entry = LIST_FIRST(&ifm->ifm_list); entry;
 	     entry = LIST_FIRST(&ifm->ifm_list)) {
 		LIST_REMOVE(entry, ifm_list);
 		kfree(entry);
 	}
 }

 /*
  * Add a media configuration to the list of supported media
  * for a specific interface instance.
  */
 void
 ifmedia_add(struct ifmedia *ifm, int mword, int data, void *aux)
 {
 	register struct ifmedia_entry *entry;

 #ifdef IFMEDIA_DEBUG
 	if (ifmedia_debug) {
 		if (ifm == NULL) {
 			printk("ifmedia_add: null ifm\n");
 			return;
 		}
 		printk("Adding entry for ");
 		ifmedia_printword(mword);
 	}
 #endif

 	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
 	if (entry == NULL)
 		panic("ifmedia_add: can't malloc entry");

 	entry->ifm_media = mword;
 	entry->ifm_data = data;
 	entry->ifm_aux = aux;

 	LIST_INSERT_HEAD(&ifm->ifm_list, entry, ifm_list);
 }

 /*
  * Add an array of media configurations to the list of
  * supported media for a specific interface instance.
  */
 void
 ifmedia_list_add(struct ifmedia *ifm, struct ifmedia_entry *lp, int count)
 {
 	int i;

 	for (i = 0; i < count; i++)
 		ifmedia_add(ifm, lp[i].ifm_media, lp[i].ifm_data, lp[i].ifm_aux);
 }

 /*
  * Set the default active media.
  *
  * Called by device-specific code which is assumed to have already
  * selected the default media in hardware.  We do _not_ call the
  * media-change callback.
  */
 void
 ifmedia_set(struct ifmedia *ifm, int target)
 {
 	struct ifmedia_entry *match;

 	match = ifmedia_match(ifm, target, ifm->ifm_mask);

 	if (match == NULL) {
 		printk("ifmedia_set: no match for 0x%x/0x%x\n",
 			target, ~ifm->ifm_mask);
 		panic("ifmedia_set");
 	}
 	ifm->ifm_cur = match;

 #ifdef IFMEDIA_DEBUG
 	if (ifmedia_debug) {
 		printk("ifmedia_set: target ");
 		ifmedia_printword(target);
 		printk("ifmedia_set: setting to ");
 		ifmedia_printword(ifm->ifm_cur->ifm_media);
 	}
 #endif
 }

 /*
  * Device-independent media ioctl support function.
  */
 int
 ifmedia_ioctl(struct net_device *dev, struct ifreq *ifr,
 	struct ifmedia *ifm, u_long cmd)
 {
 	struct ifmedia_entry *match;
 	struct ifmediareq *ifmr = (struct ifmediareq *) ifr;
 	int error = 0, sticky;

 	if (dev == NULL || ifr == NULL || ifm == NULL)
 		return -EINVAL;

 	switch (cmd) {
 	/*
 	 * Set the current media.
 	 */
 	case  SIOCSIFMEDIA:
 	{
 		struct ifmedia_entry *oldentry;
 		int oldmedia;
 		int newmedia = ifr->ifr_media;

 		match = ifmedia_match(ifm, newmedia, ifm->ifm_mask);
 		if (match == NULL) {
 #ifdef IFMEDIA_DEBUG
 			if (ifmedia_debug) {
 				printk("ifmedia_ioctl: no media found for 0x%x\n",
 					newmedia);
 			}
 #endif
 			return -ENXIO;
 		}

 		/*
 		 * If no change, we're done.
 		 * XXX Automedia may invole software intervention.
 		 *     Keep going in case the the connected media changed.
 		 *     Similarly, if best match changed (kernel debugger?).
 		 */
 		if ((IFM_SUBTYPE(newmedia) != IFM_AUTO) &&
 		    (newmedia == ifm->ifm_media) &&
 		    (match == ifm->ifm_cur))
 			return 0;

 		/*
 		 * We found a match, now make the driver switch to it.
 		 * Make sure to preserve our old media type in case the
 		 * driver can't switch.
 		 */
 #ifdef IFMEDIA_DEBUG
 		if (ifmedia_debug) {
 			printk("ifmedia_ioctl: switching %s to ", dev->name);
 			ifmedia_printword(match->ifm_media);
 		}
 #endif
 		oldentry = ifm->ifm_cur;
 		oldmedia = ifm->ifm_media;
 		ifm->ifm_cur = match;
 		ifm->ifm_media = newmedia;
 		error = (*ifm->ifm_change)(netdev_priv(dev));
 		if ((error < 0) && (error != -ENETRESET)) {
 			ifm->ifm_cur = oldentry;
 			ifm->ifm_media = oldmedia;
 		}
 		break;
 	}

 	/*
 	 * Get list of available media and current media on interface.
 	 */
 	case  SIOCGIFMEDIA:
 	{
 		struct ifmedia_entry *ep;
 		int *kptr, count;
 		int usermax;	/* user requested max */

 		kptr = NULL;		/* XXX gcc */

 		ifmr->ifm_active = ifmr->ifm_current = ifm->ifm_cur ?
 			ifm->ifm_cur->ifm_media : IFM_NONE;
 		ifmr->ifm_mask = ifm->ifm_mask;
 		ifmr->ifm_status = 0;
 		(*ifm->ifm_status)(netdev_priv(dev), ifmr);

 		count = 0;
 		usermax = 0;

 		/*
 		 * If there are more interfaces on the list, count
 		 * them.  This allows the caller to set ifmr->ifm_count
 		 * to 0 on the first call to know how much space to
 		 * allocate.
 		 */
 		LIST_FOREACH(ep, &ifm->ifm_list, ifm_list)
 			usermax++;

 		/*
 		 * Don't allow the user to ask for too many
 		 * or a negative number.
 		 */
 		if (ifmr->ifm_count > usermax)
 			ifmr->ifm_count = usermax;
 		else if (ifmr->ifm_count < 0)
 			return (-EINVAL);

 		if (ifmr->ifm_count != 0) {
 			kptr = (int *)kmalloc(ifmr->ifm_count * sizeof(int),
 			    GFP_KERNEL);

 			if (kptr == NULL)
 				return (-ENOMEM);
 			/*
 			 * Get the media words from the interface's list.
 			 */
 			ep = LIST_FIRST(&ifm->ifm_list);
 			for (; ep != NULL && count < ifmr->ifm_count;
 			    ep = LIST_NEXT(ep, ifm_list), count++)
 				kptr[count] = ep->ifm_media;

 			if (ep != NULL)
 				error = -E2BIG;	/* oops! */
 		} else
 			count = usermax;

 		/*
 		 * We do the copyout on E2BIG, because that's
 		 * just our way of telling userland that there
 		 * are more.  This is the behavior I've observed
 		 * under BSD/OS 3.0
 		 */
 		sticky = error;
 		if ((error == 0 || error == -E2BIG) && ifmr->ifm_count != 0) {
 			error = copy_to_user(ifmr->ifm_ulist,
 				kptr, ifmr->ifm_count * sizeof(int));
 		}

 		if (error == 0)
 			error = sticky;

 		if (ifmr->ifm_count != 0)
 			kfree(kptr);

 		ifmr->ifm_count = count;
 		break;
 	}

 	default:
 		return -EINVAL;
 	}

 	return error;
 }

 /*
  * Find media entry matching a given ifm word.
  *
  */
 struct ifmedia_entry *
 ifmedia_match(struct ifmedia *ifm, int target, int mask)
 {
 	struct ifmedia_entry *match, *next;

 	match = NULL;
 	mask = ~mask;

 	LIST_FOREACH(next, &ifm->ifm_list, ifm_list) {
 		if ((next->ifm_media & mask) == (target & mask)) {
 #if defined(IFMEDIA_DEBUG) || defined(DIAGNOSTIC)
 			if (match)
 				printk("ifmedia_match: multiple match for "
 					"0x%x/0x%x\n", target, mask);
 #endif
 			match = next;
 		}
 	}

 	return match;
 }

 #ifdef IFMEDIA_DEBUG
 struct ifmedia_description ifm_type_descriptions[] =
     IFM_TYPE_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_ethernet_descriptions[] =
     IFM_SUBTYPE_ETHERNET_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_ethernet_option_descriptions[] =
     IFM_SUBTYPE_ETHERNET_OPTION_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_tokenring_descriptions[] =
     IFM_SUBTYPE_TOKENRING_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_tokenring_option_descriptions[] =
     IFM_SUBTYPE_TOKENRING_OPTION_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_fddi_descriptions[] =
     IFM_SUBTYPE_FDDI_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_fddi_option_descriptions[] =
     IFM_SUBTYPE_FDDI_OPTION_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_ieee80211_descriptions[] =
     IFM_SUBTYPE_IEEE80211_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_ieee80211_option_descriptions[] =
     IFM_SUBTYPE_IEEE80211_OPTION_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_ieee80211_mode_descriptions[] =
     IFM_SUBTYPE_IEEE80211_MODE_DESCRIPTIONS;

 struct ifmedia_description ifm_subtype_shared_descriptions[] =
     IFM_SUBTYPE_SHARED_DESCRIPTIONS;

 struct ifmedia_description ifm_shared_option_descriptions[] =
     IFM_SHARED_OPTION_DESCRIPTIONS;

 struct ifmedia_type_to_subtype {		/* XXX: right place for declaration? */
 	struct ifmedia_description *subtypes;
 	struct ifmedia_description *options;
 	struct ifmedia_description *modes;
 };

 /* must be in the same order as IFM_TYPE_DESCRIPTIONS */
 struct ifmedia_type_to_subtype ifmedia_types_to_subtypes[] = {
 	{ &ifm_subtype_ethernet_descriptions[0],
 	  &ifm_subtype_ethernet_option_descriptions[0],
 	  NULL, },
 	{ &ifm_subtype_tokenring_descriptions[0],
 	  &ifm_subtype_tokenring_option_descriptions[0],
 	  NULL, },
 	{ &ifm_subtype_fddi_descriptions[0],
 	  &ifm_subtype_fddi_option_descriptions[0],
 	  NULL, },
 	{ &ifm_subtype_ieee80211_descriptions[0],
 	  &ifm_subtype_ieee80211_option_descriptions[0],
 	  &ifm_subtype_ieee80211_mode_descriptions[0] },
 };

 /*
  * print a media word.
  */
 static void
 ifmedia_printword(int ifmw)
 {
 	struct ifmedia_description *desc;
 	struct ifmedia_type_to_subtype *ttos;
 	int seen_option = 0;

 	/* Find the top-level interface type. */
 	for (desc = ifm_type_descriptions, ttos = ifmedia_types_to_subtypes;
 	    desc->ifmt_string != NULL; desc++, ttos++)
 		if (IFM_TYPE(ifmw) == desc->ifmt_word)
 			break;
 	if (desc->ifmt_string == NULL) {
 		printk("<unknown type>\n");
 		return;
 	}
 	printk(desc->ifmt_string);

 	/* Any mode. */
 	for (desc = ttos->modes; desc && desc->ifmt_string != NULL; desc++)
 		if (IFM_MODE(ifmw) == desc->ifmt_word) {
 			if (desc->ifmt_string != NULL)
 				printk(" mode %s", desc->ifmt_string);
 			break;
 		}

 	/*
 	 * Check for the shared subtype descriptions first, then the
 	 * type-specific ones.
 	 */
 	for (desc = ifm_subtype_shared_descriptions;
 	    desc->ifmt_string != NULL; desc++)
 		if (IFM_SUBTYPE(ifmw) == desc->ifmt_word)
 			goto got_subtype;

 	for (desc = ttos->subtypes; desc->ifmt_string != NULL; desc++)
 		if (IFM_SUBTYPE(ifmw) == desc->ifmt_word)
 			break;
 	if (desc->ifmt_string == NULL) {
 		printk(" <unknown subtype>\n");
 		return;
 	}

  got_subtype:
 	printk(" %s", desc->ifmt_string);

 	/*
 	 * Look for shared options.
 	 */
 	for (desc = ifm_shared_option_descriptions;
 	    desc->ifmt_string != NULL; desc++) {
 		if (ifmw & desc->ifmt_word) {
 			if (seen_option == 0)
 				printk(" <");
 			printk("%s%s", seen_option++ ? "," : "",
 			    desc->ifmt_string);
 		}
 	}

 	/*
 	 * Look for subtype-specific options.
 	 */
 	for (desc = ttos->options; desc->ifmt_string != NULL; desc++) {
 		if (ifmw & desc->ifmt_word) {
 			if (seen_option == 0)
 				printk(" <");
 			printk("%s%s", seen_option++ ? "," : "",
 			    desc->ifmt_string);
 		}
 	}
 	printk("%s\n", seen_option ? ">" : "");
 }
 #endif /* IFMEDIA_DEBUG */

 EXPORT_SYMBOL(ifmedia_ioctl);
	/*
	* Copyright (c) 1997
	* Jonathan Stone and Jason R. Thorpe. All rights reserved.
	*
	* This software is derived from information provided by Matt Thomas.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. All advertising materials mentioning features or use of this software
	* must display the following acknowledgement:
	* This product includes software developed by Jonathan Stone
	* and Jason R. Thorpe for the NetBSD Project.
	* 4. The names of the authors may not be used to endorse or promote products
	* derived from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
	* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
	* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.
	*
	* $Id: if_media.c 1721 2006-09-20 08:45:13Z mentor $
	*/

	/*
	* BSD/OS-compatible network interface media selection.
	*
	* Where it is safe to do so, this code strays slightly from the BSD/OS
	* design. Software which uses the API (device drivers, basically)
	* shouldn't notice any difference.
	*
	* Many thanks to Matt Thomas for providing the information necessary
	* to implement this interface.
	*/

	#ifndef EXPORT_SYMTAB
	#define EXPORT_SYMTAB
	#endif

	#ifndef AUTOCONF_INCLUDED
	#include <linux/config.h>
	#endif
	#include <linux/version.h>
	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/slab.h>
	#include <linux/if.h>
	#include <linux/netdevice.h>
	#ifndef ifr_media
	#define ifr_media ifr_ifru.ifru_ivalue
	#endif

	#include <asm/uaccess.h>

	#include "net80211/if_media.h"

	/*
	* Compile-time options:
	* IFMEDIA_DEBUG:
	* turn on implementation-level debug printfs.
	* Useful for debugging newly-ported drivers.
	*/

	struct ifmedia_entry ifmedia_match(struct ifmedia , int, int);

	#ifdef IFMEDIA_DEBUG
	int ifmedia_debug = 0;
	static void ifmedia_printword(int);
	#endif

	/*
	* Initialize if_media struct for a specific interface instance.
	*/
	void
	ifmedia_init(struct ifmedia *ifm, int dontcare_mask,
	ifm_change_cb_t change_callback, ifm_stat_cb_t status_callback)
	{
	LIST_INIT(&ifm->ifm_list);
	ifm->ifm_cur = NULL;
	ifm->ifm_media = 0;
	ifm->ifm_mask = dontcare_mask; /* IF don't-care bits */
	ifm->ifm_change = change_callback;
	ifm->ifm_status = status_callback;
	}

	void
	ifmedia_removeall(struct ifmedia *ifm)
	{
	struct ifmedia_entry *entry;

	for (entry = LIST_FIRST(&ifm->ifm_list); entry;
	entry = LIST_FIRST(&ifm->ifm_list)) {
	LIST_REMOVE(entry, ifm_list);
	kfree(entry);
	}
	}

	/*
	* Add a media configuration to the list of supported media
	* for a specific interface instance.
	*/
	void
	ifmedia_add(struct ifmedia ifm, int mword, int data, void aux)
	{
	register struct ifmedia_entry *entry;

	#ifdef IFMEDIA_DEBUG
	if (ifmedia_debug) {
	if (ifm == NULL) {
	printk("ifmedia_add: null ifm\n");
	return;
	}
	printk("Adding entry for ");
	ifmedia_printword(mword);
	}
	#endif

	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
	if (entry == NULL)
	panic("ifmedia_add: can't malloc entry");

	entry->ifm_media = mword;
	entry->ifm_data = data;
	entry->ifm_aux = aux;

	LIST_INSERT_HEAD(&ifm->ifm_list, entry, ifm_list);
	}

	/*
	* Add an array of media configurations to the list of
	* supported media for a specific interface instance.
	*/
	void
	ifmedia_list_add(struct ifmedia ifm, struct ifmedia_entry lp, int count)
	{
	int i;

	for (i = 0; i < count; i++)
	ifmedia_add(ifm, lp[i].ifm_media, lp[i].ifm_data, lp[i].ifm_aux);
	}

	/*
	* Set the default active media.
	*
	* Called by device-specific code which is assumed to have already
	* selected the default media in hardware. We do _not_ call the
	* media-change callback.
	*/
	void
	ifmedia_set(struct ifmedia *ifm, int target)
	{
	struct ifmedia_entry *match;

	match = ifmedia_match(ifm, target, ifm->ifm_mask);

	if (match == NULL) {
	printk("ifmedia_set: no match for 0x%x/0x%x\n",
	target, ~ifm->ifm_mask);
	panic("ifmedia_set");
	}
	ifm->ifm_cur = match;

	#ifdef IFMEDIA_DEBUG
	if (ifmedia_debug) {
	printk("ifmedia_set: target ");
	ifmedia_printword(target);
	printk("ifmedia_set: setting to ");
	ifmedia_printword(ifm->ifm_cur->ifm_media);
	}
	#endif
	}

	/*
	* Device-independent media ioctl support function.
	*/
	int
	ifmedia_ioctl(struct net_device dev, struct ifreq ifr,
	struct ifmedia *ifm, u_long cmd)
	{
	struct ifmedia_entry *match;
	struct ifmediareq ifmr = (struct ifmediareq ) ifr;
	int error = 0, sticky;

	if (dev == NULL \|\| ifr == NULL \|\| ifm == NULL)
	return -EINVAL;

	switch (cmd) {
	/*
	* Set the current media.
	*/
	case SIOCSIFMEDIA:
	{
	struct ifmedia_entry *oldentry;
	int oldmedia;
	int newmedia = ifr->ifr_media;

	match = ifmedia_match(ifm, newmedia, ifm->ifm_mask);
	if (match == NULL) {
	#ifdef IFMEDIA_DEBUG
	if (ifmedia_debug) {
	printk("ifmedia_ioctl: no media found for 0x%x\n",
	newmedia);
	}
	#endif
	return -ENXIO;
	}

	/*
	* If no change, we're done.
	* XXX Automedia may invole software intervention.
	* Keep going in case the the connected media changed.
	* Similarly, if best match changed (kernel debugger?).
	*/
	if ((IFM_SUBTYPE(newmedia) != IFM_AUTO) &&
	(newmedia == ifm->ifm_media) &&
	(match == ifm->ifm_cur))
	return 0;

	/*
	* We found a match, now make the driver switch to it.
	* Make sure to preserve our old media type in case the
	* driver can't switch.
	*/
	#ifdef IFMEDIA_DEBUG
	if (ifmedia_debug) {
	printk("ifmedia_ioctl: switching %s to ", dev->name);
	ifmedia_printword(match->ifm_media);
	}
	#endif
	oldentry = ifm->ifm_cur;
	oldmedia = ifm->ifm_media;
	ifm->ifm_cur = match;
	ifm->ifm_media = newmedia;
	error = (*ifm->ifm_change)(netdev_priv(dev));
	if ((error < 0) && (error != -ENETRESET)) {
	ifm->ifm_cur = oldentry;
	ifm->ifm_media = oldmedia;
	}
	break;
	}

	/*
	* Get list of available media and current media on interface.
	*/
	case SIOCGIFMEDIA:
	{
	struct ifmedia_entry *ep;
	int *kptr, count;
	int usermax; /* user requested max */

	kptr = NULL; /* XXX gcc */

	ifmr->ifm_active = ifmr->ifm_current = ifm->ifm_cur ?
	ifm->ifm_cur->ifm_media : IFM_NONE;
	ifmr->ifm_mask = ifm->ifm_mask;
	ifmr->ifm_status = 0;
	(*ifm->ifm_status)(netdev_priv(dev), ifmr);

	count = 0;
	usermax = 0;

	/*
	* If there are more interfaces on the list, count
	* them. This allows the caller to set ifmr->ifm_count
	* to 0 on the first call to know how much space to
	* allocate.
	*/
	LIST_FOREACH(ep, &ifm->ifm_list, ifm_list)
	usermax++;

	/*
	* Don't allow the user to ask for too many
	* or a negative number.
	*/
	if (ifmr->ifm_count > usermax)
	ifmr->ifm_count = usermax;
	else if (ifmr->ifm_count < 0)
	return (-EINVAL);

	if (ifmr->ifm_count != 0) {
	kptr = (int )kmalloc(ifmr->ifm_count sizeof(int),
	GFP_KERNEL);

	if (kptr == NULL)
	return (-ENOMEM);
	/*
	* Get the media words from the interface's list.
	*/
	ep = LIST_FIRST(&ifm->ifm_list);
	for (; ep != NULL && count < ifmr->ifm_count;
	ep = LIST_NEXT(ep, ifm_list), count++)
	kptr[count] = ep->ifm_media;

	if (ep != NULL)
	error = -E2BIG; /* oops! */
	} else
	count = usermax;

	/*
	* We do the copyout on E2BIG, because that's
	* just our way of telling userland that there
	* are more. This is the behavior I've observed
	* under BSD/OS 3.0
	*/
	sticky = error;
	if ((error == 0 \|\| error == -E2BIG) && ifmr->ifm_count != 0) {
	error = copy_to_user(ifmr->ifm_ulist,
	kptr, ifmr->ifm_count * sizeof(int));
	}

	if (error == 0)
	error = sticky;

	if (ifmr->ifm_count != 0)
	kfree(kptr);

	ifmr->ifm_count = count;
	break;
	}

	default:
	return -EINVAL;
	}

	return error;
	}

	/*
	* Find media entry matching a given ifm word.
	*
	*/
	struct ifmedia_entry *
	ifmedia_match(struct ifmedia *ifm, int target, int mask)
	{
	struct ifmedia_entry match, next;

	match = NULL;
	mask = ~mask;

	LIST_FOREACH(next, &ifm->ifm_list, ifm_list) {
	if ((next->ifm_media & mask) == (target & mask)) {
	#if defined(IFMEDIA_DEBUG) \|\| defined(DIAGNOSTIC)
	if (match)
	printk("ifmedia_match: multiple match for "
	"0x%x/0x%x\n", target, mask);
	#endif
	match = next;
	}
	}

	return match;
	}

	#ifdef IFMEDIA_DEBUG
	struct ifmedia_description ifm_type_descriptions[] =
	IFM_TYPE_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_ethernet_descriptions[] =
	IFM_SUBTYPE_ETHERNET_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_ethernet_option_descriptions[] =
	IFM_SUBTYPE_ETHERNET_OPTION_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_tokenring_descriptions[] =
	IFM_SUBTYPE_TOKENRING_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_tokenring_option_descriptions[] =
	IFM_SUBTYPE_TOKENRING_OPTION_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_fddi_descriptions[] =
	IFM_SUBTYPE_FDDI_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_fddi_option_descriptions[] =
	IFM_SUBTYPE_FDDI_OPTION_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_ieee80211_descriptions[] =
	IFM_SUBTYPE_IEEE80211_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_ieee80211_option_descriptions[] =
	IFM_SUBTYPE_IEEE80211_OPTION_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_ieee80211_mode_descriptions[] =
	IFM_SUBTYPE_IEEE80211_MODE_DESCRIPTIONS;

	struct ifmedia_description ifm_subtype_shared_descriptions[] =
	IFM_SUBTYPE_SHARED_DESCRIPTIONS;

	struct ifmedia_description ifm_shared_option_descriptions[] =
	IFM_SHARED_OPTION_DESCRIPTIONS;

	struct ifmedia_type_to_subtype { /* XXX: right place for declaration? */
	struct ifmedia_description *subtypes;
	struct ifmedia_description *options;
	struct ifmedia_description *modes;
	};

	/* must be in the same order as IFM_TYPE_DESCRIPTIONS */
	struct ifmedia_type_to_subtype ifmedia_types_to_subtypes[] = {
	{ &ifm_subtype_ethernet_descriptions[0],
	&ifm_subtype_ethernet_option_descriptions[0],
	NULL, },
	{ &ifm_subtype_tokenring_descriptions[0],
	&ifm_subtype_tokenring_option_descriptions[0],
	NULL, },
	{ &ifm_subtype_fddi_descriptions[0],
	&ifm_subtype_fddi_option_descriptions[0],
	NULL, },
	{ &ifm_subtype_ieee80211_descriptions[0],
	&ifm_subtype_ieee80211_option_descriptions[0],
	&ifm_subtype_ieee80211_mode_descriptions[0] },
	};

	/*
	* print a media word.
	*/
	static void
	ifmedia_printword(int ifmw)
	{
	struct ifmedia_description *desc;
	struct ifmedia_type_to_subtype *ttos;
	int seen_option = 0;

	/* Find the top-level interface type. */
	for (desc = ifm_type_descriptions, ttos = ifmedia_types_to_subtypes;
	desc->ifmt_string != NULL; desc++, ttos++)
	if (IFM_TYPE(ifmw) == desc->ifmt_word)
	break;
	if (desc->ifmt_string == NULL) {
	printk("<unknown type>\n");
	return;
	}
	printk(desc->ifmt_string);

	/* Any mode. */
	for (desc = ttos->modes; desc && desc->ifmt_string != NULL; desc++)
	if (IFM_MODE(ifmw) == desc->ifmt_word) {
	if (desc->ifmt_string != NULL)
	printk(" mode %s", desc->ifmt_string);
	break;
	}

	/*
	* Check for the shared subtype descriptions first, then the
	* type-specific ones.
	*/
	for (desc = ifm_subtype_shared_descriptions;
	desc->ifmt_string != NULL; desc++)
	if (IFM_SUBTYPE(ifmw) == desc->ifmt_word)
	goto got_subtype;

	for (desc = ttos->subtypes; desc->ifmt_string != NULL; desc++)
	if (IFM_SUBTYPE(ifmw) == desc->ifmt_word)
	break;
	if (desc->ifmt_string == NULL) {
	printk(" <unknown subtype>\n");
	return;
	}

	got_subtype:
	printk(" %s", desc->ifmt_string);

	/*
	* Look for shared options.
	*/
	for (desc = ifm_shared_option_descriptions;
	desc->ifmt_string != NULL; desc++) {
	if (ifmw & desc->ifmt_word) {
	if (seen_option == 0)
	printk(" <");
	printk("%s%s", seen_option++ ? "," : "",
	desc->ifmt_string);
	}
	}

	/*
	* Look for subtype-specific options.
	*/
	for (desc = ttos->options; desc->ifmt_string != NULL; desc++) {
	if (ifmw & desc->ifmt_word) {
	if (seen_option == 0)
	printk(" <");
	printk("%s%s", seen_option++ ? "," : "",
	desc->ifmt_string);
	}
	}
	printk("%s\n", seen_option ? ">" : "");
	}
	#endif /* IFMEDIA_DEBUG */

	EXPORT_SYMBOL(ifmedia_ioctl);