freebsd-skq/sys/net80211/ieee80211_power.c
adrian 4f57c7deee Update ieee80211_sta_tim_notify() to do double duty - handle STA sleep
to awake transition as well as handle waking up a VAP in STA powersave
mode if it's in bgscan.

This was a reasonably hairy bug to try and figure out and it became
more obvious because of stuff I've done.

Specifically:

* a NIC would go into bgscan mode - either because of a bgscan timer
  or wpa_supplicant asked it to;
* the AP would indicate there's traffic for the STA by setting the TIM
  bitmap bit for it;
* mindwell would be met during scan, so it'd wake up and break out of
  the scan loop in scan_task(), but
* because the scan wasn't completed, it wouldn't bring the VAP out of
  STA mode powersave (so it wouldn't tell the AP about it and it would
  block VAP TX);
* .. but because we kept seeing the TIM bit set, ic->ic_lastdata was
  being constantly updated, and ..
* bgscancont() would thus never say "yes we can continue a bgscan"
  so the bgscan would hang and never make progress.

Now, I do see this particular state occur on iwn(4) - /however/ -
this NIC has the firmware call ieee80211_scan_next() once the firmware
scan for that channel has completed.  This has the effect of moving
the scan along to the next channel.  I do see the debug that I'm adding
where we see a beacon with a TIM bit set whilst we're in bgscan, so
the condition about waking up to receive traffic is triggering.
It just won't cause a hang.

For other NICs - all of the USB ones and at least ath(4) -
ieee80211_scan_next() / ieee80211_scan_done() isn't called.
So it relies upon the mindwell timer, the beacon receive and the
beacon / probe response -> ieee80211_add_scan() to move along
the scan state.

In the above case, mindwell triggered, there's no beacons triggering
the scan_add code to move things along, and we weren't waking things
up when seeing the TIM set for us.  So it just hung until the interface
was dropped.

So, the short-term fix here is to do what the comment in scan_task()
says - if we are in bgscan mode and we see our TIM bit set, just wake
up the VAP.  If it's already awake then it's a nop.  If we're awake
then we transition to awake and handle the traffic.  Once there's no
TX or RX traffic going on, ic->ic_lastdata won't be updated anymore
and bgscancont() will continue.

This was triggered more often after my initial SLEEP state handling
for software sleep states - because now I update ic->ic_lastdata
upon seeing a TIM bit set, not just the RX of the subsequent traffic.
That's needed so the thing doesn't ping-pong up and down between
seeing the TIM bit set, sending the "I'm awake" NULL data frame, and
starting to receive data from the AP.

I'd like to subsequently split ic_lastdata into two - one for TX and
one for RX - so it becomes easier to use the correct one (or both!)
when making decisions like whether to scan, go to sleep, etc.

I'd appreciate this getting some further testing.

Tested:

* rsu(4), STA mode, bgscan on
* iwn(4), STA mode, bgscan on
2014-12-21 04:58:45 +00:00

663 lines
18 KiB
C

/*-
* Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
* All rights reserved.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* IEEE 802.11 power save support.
*/
#include "opt_wlan.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_media.h>
#include <net/ethernet.h>
#include <net80211/ieee80211_var.h>
#include <net/bpf.h>
static void ieee80211_update_ps(struct ieee80211vap *, int);
static int ieee80211_set_tim(struct ieee80211_node *, int);
static MALLOC_DEFINE(M_80211_POWER, "80211power", "802.11 power save state");
void
ieee80211_power_attach(struct ieee80211com *ic)
{
}
void
ieee80211_power_detach(struct ieee80211com *ic)
{
}
void
ieee80211_power_vattach(struct ieee80211vap *vap)
{
if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
vap->iv_opmode == IEEE80211_M_IBSS) {
/* NB: driver should override */
vap->iv_update_ps = ieee80211_update_ps;
vap->iv_set_tim = ieee80211_set_tim;
}
vap->iv_node_ps = ieee80211_node_pwrsave;
vap->iv_sta_ps = ieee80211_sta_pwrsave;
}
void
ieee80211_power_latevattach(struct ieee80211vap *vap)
{
/*
* Allocate these only if needed. Beware that we
* know adhoc mode doesn't support ATIM yet...
*/
if (vap->iv_opmode == IEEE80211_M_HOSTAP) {
vap->iv_tim_len = howmany(vap->iv_max_aid,8) * sizeof(uint8_t);
vap->iv_tim_bitmap = (uint8_t *) malloc(vap->iv_tim_len,
M_80211_POWER, M_NOWAIT | M_ZERO);
if (vap->iv_tim_bitmap == NULL) {
printf("%s: no memory for TIM bitmap!\n", __func__);
/* XXX good enough to keep from crashing? */
vap->iv_tim_len = 0;
}
}
}
void
ieee80211_power_vdetach(struct ieee80211vap *vap)
{
if (vap->iv_tim_bitmap != NULL) {
free(vap->iv_tim_bitmap, M_80211_POWER);
vap->iv_tim_bitmap = NULL;
}
}
void
ieee80211_psq_init(struct ieee80211_psq *psq, const char *name)
{
memset(psq, 0, sizeof(*psq));
psq->psq_maxlen = IEEE80211_PS_MAX_QUEUE;
IEEE80211_PSQ_INIT(psq, name); /* OS-dependent setup */
}
void
ieee80211_psq_cleanup(struct ieee80211_psq *psq)
{
#if 0
psq_drain(psq); /* XXX should not be needed? */
#else
KASSERT(psq->psq_len == 0, ("%d frames on ps q", psq->psq_len));
#endif
IEEE80211_PSQ_DESTROY(psq); /* OS-dependent cleanup */
}
/*
* Return the highest priority frame in the ps queue.
*/
struct mbuf *
ieee80211_node_psq_dequeue(struct ieee80211_node *ni, int *qlen)
{
struct ieee80211_psq *psq = &ni->ni_psq;
struct ieee80211_psq_head *qhead;
struct mbuf *m;
IEEE80211_PSQ_LOCK(psq);
qhead = &psq->psq_head[0];
again:
if ((m = qhead->head) != NULL) {
if ((qhead->head = m->m_nextpkt) == NULL)
qhead->tail = NULL;
KASSERT(qhead->len > 0, ("qhead len %d", qhead->len));
qhead->len--;
KASSERT(psq->psq_len > 0, ("psq len %d", psq->psq_len));
psq->psq_len--;
m->m_nextpkt = NULL;
}
if (m == NULL && qhead == &psq->psq_head[0]) {
/* Algol-68 style for loop */
qhead = &psq->psq_head[1];
goto again;
}
if (qlen != NULL)
*qlen = psq->psq_len;
IEEE80211_PSQ_UNLOCK(psq);
return m;
}
/*
* Reclaim an mbuf from the ps q. If marked with M_ENCAP
* we assume there is a node reference that must be relcaimed.
*/
static void
psq_mfree(struct mbuf *m)
{
if (m->m_flags & M_ENCAP) {
struct ieee80211_node *ni = (void *) m->m_pkthdr.rcvif;
ieee80211_free_node(ni);
}
m->m_nextpkt = NULL;
m_freem(m);
}
/*
* Clear any frames queued in the power save queue.
* The number of frames that were present is returned.
*/
static int
psq_drain(struct ieee80211_psq *psq)
{
struct ieee80211_psq_head *qhead;
struct mbuf *m;
int qlen;
IEEE80211_PSQ_LOCK(psq);
qlen = psq->psq_len;
qhead = &psq->psq_head[0];
again:
while ((m = qhead->head) != NULL) {
qhead->head = m->m_nextpkt;
psq_mfree(m);
}
qhead->tail = NULL;
qhead->len = 0;
if (qhead == &psq->psq_head[0]) { /* Algol-68 style for loop */
qhead = &psq->psq_head[1];
goto again;
}
psq->psq_len = 0;
IEEE80211_PSQ_UNLOCK(psq);
return qlen;
}
/*
* Clear any frames queued in the power save queue.
* The number of frames that were present is returned.
*/
int
ieee80211_node_psq_drain(struct ieee80211_node *ni)
{
return psq_drain(&ni->ni_psq);
}
/*
* Age frames on the power save queue. The aging interval is
* 4 times the listen interval specified by the station. This
* number is factored into the age calculations when the frame
* is placed on the queue. We store ages as time differences
* so we can check and/or adjust only the head of the list.
* If a frame's age exceeds the threshold then discard it.
* The number of frames discarded is returned so the caller
* can check if it needs to adjust the tim.
*/
int
ieee80211_node_psq_age(struct ieee80211_node *ni)
{
struct ieee80211_psq *psq = &ni->ni_psq;
int discard = 0;
if (psq->psq_len != 0) {
#ifdef IEEE80211_DEBUG
struct ieee80211vap *vap = ni->ni_vap;
#endif
struct ieee80211_psq_head *qhead;
struct mbuf *m;
IEEE80211_PSQ_LOCK(psq);
qhead = &psq->psq_head[0];
again:
while ((m = qhead->head) != NULL &&
M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"discard frame, age %u", M_AGE_GET(m));
if ((qhead->head = m->m_nextpkt) == NULL)
qhead->tail = NULL;
KASSERT(qhead->len > 0, ("qhead len %d", qhead->len));
qhead->len--;
KASSERT(psq->psq_len > 0, ("psq len %d", psq->psq_len));
psq->psq_len--;
psq_mfree(m);
discard++;
}
if (qhead == &psq->psq_head[0]) { /* Algol-68 style for loop */
qhead = &psq->psq_head[1];
goto again;
}
if (m != NULL)
M_AGE_SUB(m, IEEE80211_INACT_WAIT);
IEEE80211_PSQ_UNLOCK(psq);
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"discard %u frames for age", discard);
IEEE80211_NODE_STAT_ADD(ni, ps_discard, discard);
}
return discard;
}
/*
* Handle a change in the PS station occupancy.
*/
static void
ieee80211_update_ps(struct ieee80211vap *vap, int nsta)
{
KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP ||
vap->iv_opmode == IEEE80211_M_IBSS,
("operating mode %u", vap->iv_opmode));
}
/*
* Indicate whether there are frames queued for a station in power-save mode.
*/
static int
ieee80211_set_tim(struct ieee80211_node *ni, int set)
{
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211com *ic = ni->ni_ic;
uint16_t aid;
int changed;
KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP ||
vap->iv_opmode == IEEE80211_M_IBSS,
("operating mode %u", vap->iv_opmode));
aid = IEEE80211_AID(ni->ni_associd);
KASSERT(aid < vap->iv_max_aid,
("bogus aid %u, max %u", aid, vap->iv_max_aid));
IEEE80211_LOCK(ic);
changed = (set != (isset(vap->iv_tim_bitmap, aid) != 0));
if (changed) {
if (set) {
setbit(vap->iv_tim_bitmap, aid);
vap->iv_ps_pending++;
} else {
clrbit(vap->iv_tim_bitmap, aid);
vap->iv_ps_pending--;
}
/* NB: we know vap is in RUN state so no need to check */
vap->iv_update_beacon(vap, IEEE80211_BEACON_TIM);
}
IEEE80211_UNLOCK(ic);
return changed;
}
/*
* Save an outbound packet for a node in power-save sleep state.
* The new packet is placed on the node's saved queue, and the TIM
* is changed, if necessary.
*/
int
ieee80211_pwrsave(struct ieee80211_node *ni, struct mbuf *m)
{
struct ieee80211_psq *psq = &ni->ni_psq;
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211com *ic = ni->ni_ic;
struct ieee80211_psq_head *qhead;
int qlen, age;
IEEE80211_PSQ_LOCK(psq);
if (psq->psq_len >= psq->psq_maxlen) {
psq->psq_drops++;
IEEE80211_PSQ_UNLOCK(psq);
IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni,
"pwr save q overflow, drops %d (size %d)",
psq->psq_drops, psq->psq_len);
#ifdef IEEE80211_DEBUG
if (ieee80211_msg_dumppkts(vap))
ieee80211_dump_pkt(ni->ni_ic, mtod(m, caddr_t),
m->m_len, -1, -1);
#endif
psq_mfree(m);
return ENOSPC;
}
/*
* Tag the frame with it's expiry time and insert it in
* the appropriate queue. The aging interval is 4 times
* the listen interval specified by the station. Frames
* that sit around too long are reclaimed using this
* information.
*/
/* TU -> secs. XXX handle overflow? */
age = IEEE80211_TU_TO_MS((ni->ni_intval * ic->ic_bintval) << 2) / 1000;
/*
* Encapsulated frames go on the high priority queue,
* other stuff goes on the low priority queue. We use
* this to order frames returned out of the driver
* ahead of frames we collect in ieee80211_start.
*/
if (m->m_flags & M_ENCAP)
qhead = &psq->psq_head[0];
else
qhead = &psq->psq_head[1];
if (qhead->tail == NULL) {
struct mbuf *mh;
qhead->head = m;
/*
* Take care to adjust age when inserting the first
* frame of a queue and the other queue already has
* frames. We need to preserve the age difference
* relationship so ieee80211_node_psq_age works.
*/
if (qhead == &psq->psq_head[1]) {
mh = psq->psq_head[0].head;
if (mh != NULL)
age-= M_AGE_GET(mh);
} else {
mh = psq->psq_head[1].head;
if (mh != NULL) {
int nage = M_AGE_GET(mh) - age;
/* XXX is clamping to zero good 'nuf? */
M_AGE_SET(mh, nage < 0 ? 0 : nage);
}
}
} else {
qhead->tail->m_nextpkt = m;
age -= M_AGE_GET(qhead->head);
}
KASSERT(age >= 0, ("age %d", age));
M_AGE_SET(m, age);
m->m_nextpkt = NULL;
qhead->tail = m;
qhead->len++;
qlen = ++(psq->psq_len);
IEEE80211_PSQ_UNLOCK(psq);
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"save frame with age %d, %u now queued", age, qlen);
if (qlen == 1 && vap->iv_set_tim != NULL)
vap->iv_set_tim(ni, 1);
return 0;
}
/*
* Move frames from the ps q to the vap's send queue
* and/or the driver's send queue; and kick the start
* method for each, as appropriate. Note we're careful
* to preserve packet ordering here.
*/
static void
pwrsave_flushq(struct ieee80211_node *ni)
{
struct ieee80211_psq *psq = &ni->ni_psq;
struct ieee80211com *ic = ni->ni_ic;
struct ieee80211vap *vap = ni->ni_vap;
struct ieee80211_psq_head *qhead;
struct ifnet *parent, *ifp;
struct mbuf *parent_q = NULL, *ifp_q = NULL;
struct mbuf *m;
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"flush ps queue, %u packets queued", psq->psq_len);
IEEE80211_PSQ_LOCK(psq);
qhead = &psq->psq_head[0]; /* 802.11 frames */
if (qhead->head != NULL) {
/* XXX could dispatch through vap and check M_ENCAP */
parent = vap->iv_ic->ic_ifp;
/* XXX need different driver interface */
/* XXX bypasses q max and OACTIVE */
parent_q = qhead->head;
qhead->head = qhead->tail = NULL;
qhead->len = 0;
} else
parent = NULL;
qhead = &psq->psq_head[1]; /* 802.3 frames */
if (qhead->head != NULL) {
ifp = vap->iv_ifp;
/* XXX need different driver interface */
/* XXX bypasses q max and OACTIVE */
ifp_q = qhead->head;
qhead->head = qhead->tail = NULL;
qhead->len = 0;
} else
ifp = NULL;
psq->psq_len = 0;
IEEE80211_PSQ_UNLOCK(psq);
/* NB: do this outside the psq lock */
/* XXX packets might get reordered if parent is OACTIVE */
/* parent frames, should be encapsulated */
if (parent != NULL) {
while (parent_q != NULL) {
m = parent_q;
parent_q = m->m_nextpkt;
m->m_nextpkt = NULL;
/* must be encapsulated */
KASSERT((m->m_flags & M_ENCAP),
("%s: parentq with non-M_ENCAP frame!\n",
__func__));
/*
* For encaped frames, we need to free the node
* reference upon failure.
*/
if (ieee80211_parent_xmitpkt(ic, m) != 0)
ieee80211_free_node(ni);
}
}
/* VAP frames, aren't encapsulated */
if (ifp != NULL) {
while (ifp_q != NULL) {
m = ifp_q;
ifp_q = m->m_nextpkt;
m->m_nextpkt = NULL;
KASSERT((!(m->m_flags & M_ENCAP)),
("%s: vapq with M_ENCAP frame!\n", __func__));
(void) ieee80211_vap_xmitpkt(vap, m);
}
}
}
/*
* Handle station power-save state change.
*/
void
ieee80211_node_pwrsave(struct ieee80211_node *ni, int enable)
{
struct ieee80211vap *vap = ni->ni_vap;
int update;
update = 0;
if (enable) {
if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) {
vap->iv_ps_sta++;
update = 1;
}
ni->ni_flags |= IEEE80211_NODE_PWR_MGT;
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"power save mode on, %u sta's in ps mode", vap->iv_ps_sta);
if (update)
vap->iv_update_ps(vap, vap->iv_ps_sta);
} else {
if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
vap->iv_ps_sta--;
update = 1;
}
ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"power save mode off, %u sta's in ps mode", vap->iv_ps_sta);
/* NB: order here is intentional so TIM is clear before flush */
if (vap->iv_set_tim != NULL)
vap->iv_set_tim(ni, 0);
if (update) {
/* NB if no sta's in ps, driver should flush mc q */
vap->iv_update_ps(vap, vap->iv_ps_sta);
}
if (ni->ni_psq.psq_len != 0)
pwrsave_flushq(ni);
}
}
/*
* Handle power-save state change in station mode.
*/
void
ieee80211_sta_pwrsave(struct ieee80211vap *vap, int enable)
{
struct ieee80211_node *ni = vap->iv_bss;
if (!((enable != 0) ^ ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) != 0)))
return;
IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni,
"sta power save mode %s", enable ? "on" : "off");
if (!enable) {
ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
ieee80211_send_nulldata(ieee80211_ref_node(ni));
/*
* Flush any queued frames; we can do this immediately
* because we know they'll be queued behind the null
* data frame we send the ap.
* XXX can we use a data frame to take us out of ps?
*/
if (ni->ni_psq.psq_len != 0)
pwrsave_flushq(ni);
} else {
ni->ni_flags |= IEEE80211_NODE_PWR_MGT;
ieee80211_send_nulldata(ieee80211_ref_node(ni));
}
}
/*
* Handle being notified that we have data available for us in a TIM/ATIM.
*
* This may schedule a transition from _SLEEP -> _RUN if it's appropriate.
*
* In STA mode, we may have put to sleep during scan and need to be dragged
* back out of powersave mode.
*/
void
ieee80211_sta_tim_notify(struct ieee80211vap *vap, int set)
{
struct ieee80211com *ic = vap->iv_ic;
/*
* Schedule the driver state change. It'll happen at some point soon.
* Since the hardware shouldn't know that we're running just yet
* (and thus tell the peer that we're awake before we actually wake
* up said hardware), we leave the actual node state transition
* up to the transition to RUN.
*
* XXX TODO: verify that the transition to RUN will wake up the
* BSS node!
*/
IEEE80211_LOCK(vap->iv_ic);
if (set == 1 && vap->iv_state == IEEE80211_S_SLEEP) {
ieee80211_new_state_locked(vap, IEEE80211_S_RUN, 0);
IEEE80211_DPRINTF(vap, IEEE80211_MSG_POWER,
"%s: TIM=%d; wakeup\n", __func__, set);
} else if ((set == 1) && (ic->ic_flags_ext & IEEE80211_FEXT_BGSCAN)) {
/*
* XXX only do this if we're in RUN state?
*/
IEEE80211_DPRINTF(vap, IEEE80211_MSG_POWER,
"%s: wake up from bgscan vap sleep\n",
__func__);
/*
* We may be in BGSCAN mode - this means the VAP is is in STA
* mode powersave. If it is, we need to wake it up so we
* can process outbound traffic.
*/
vap->iv_sta_ps(vap, 0);
}
IEEE80211_UNLOCK(vap->iv_ic);
}
/*
* Timer check on whether the VAP has had any transmit activity.
*
* This may schedule a transition from _RUN -> _SLEEP if it's appropriate.
*/
void
ieee80211_sta_ps_timer_check(struct ieee80211vap *vap)
{
struct ieee80211com *ic = vap->iv_ic;
/* XXX lock assert */
/* For no, only do this in STA mode */
if (! (vap->iv_caps & IEEE80211_C_SWSLEEP))
goto out;
if (vap->iv_opmode != IEEE80211_M_STA)
goto out;
/* If we're not at run state, bail */
if (vap->iv_state != IEEE80211_S_RUN)
goto out;
IEEE80211_DPRINTF(vap, IEEE80211_MSG_POWER,
"%s: lastdata=%llu, ticks=%llu\n",
__func__, (unsigned long long) ic->ic_lastdata,
(unsigned long long) ticks);
/* If powersave is disabled on the VAP, don't bother */
if (! (vap->iv_flags & IEEE80211_F_PMGTON))
goto out;
/* If we've done any data within our idle interval, bail */
/* XXX hard-coded to one second for now, ew! */
if (time_after(ic->ic_lastdata + 500, ticks))
goto out;
/*
* Signify we're going into power save and transition the
* node to powersave.
*/
if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0)
vap->iv_sta_ps(vap, 1);
/*
* XXX The driver has to handle the fact that we're going
* to sleep but frames may still be transmitted;
* hopefully it and/or us will do the right thing and mark any
* transmitted frames with PWRMGT set to 1.
*/
ieee80211_new_state_locked(vap, IEEE80211_S_SLEEP, 0);
IEEE80211_DPRINTF(vap, IEEE80211_MSG_POWER,
"%s: time delta=%d msec\n", __func__,
(int) ticks_to_msecs(ticks - ic->ic_lastdata));
out:
return;
}