Add NL80211_EXT_FEATURE_VHT_IBSS flag and VHT
support for IBSS.
Signed-off-by: Janusz Dziedzic <[email protected]>
---
include/uapi/linux/nl80211.h | 2 ++
net/wireless/nl80211.c | 14 ++++++++++++--
2 files changed, 14 insertions(+), 2 deletions(-)
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 68b294e..a7ce571 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -4327,11 +4327,13 @@ enum nl80211_feature_flags {
/**
* enum nl80211_ext_feature_index - bit index of extended features.
+ * @NL80211_EXT_FEATURE_VHT_IBSS: This driver supports IBSS with VHT datarates.
*
* @NUM_NL80211_EXT_FEATURES: number of extended features.
* @MAX_NL80211_EXT_FEATURES: highest extended feature index.
*/
enum nl80211_ext_feature_index {
+ NL80211_EXT_FEATURE_VHT_IBSS,
/* add new features before the definition below */
NUM_NL80211_EXT_FEATURES,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 454d7a0..472e8f5 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -7259,8 +7259,18 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
break;
case NL80211_CHAN_WIDTH_20:
case NL80211_CHAN_WIDTH_40:
- if (rdev->wiphy.features & NL80211_FEATURE_HT_IBSS)
- break;
+ if (!(rdev->wiphy.features & NL80211_FEATURE_HT_IBSS))
+ return -EINVAL;
+ break;
+ case NL80211_CHAN_WIDTH_80:
+ case NL80211_CHAN_WIDTH_80P80:
+ case NL80211_CHAN_WIDTH_160:
+ if (!(rdev->wiphy.features & NL80211_FEATURE_HT_IBSS))
+ return -EINVAL;
+ if (!wiphy_ext_feature_isset(&rdev->wiphy,
+ NL80211_EXT_FEATURE_VHT_IBSS))
+ return -EINVAL;
+ break;
default:
return -EINVAL;
}
--
1.9.1
Add VHT80/VHT160 support for IBSS.
Drivers could activate this feature by
setting NL80211_EXT_FEATURE_VHT_IBSS flag.
Signed-off-by: Janusz Dziedzic <[email protected]>
---
net/mac80211/ht.c | 2 --
net/mac80211/ibss.c | 62 ++++++++++++++++++++++++++++++++--------
net/mac80211/ieee80211_i.h | 5 ++++
net/mac80211/mesh_plink.c | 4 +++
net/mac80211/util.c | 70 ++++++++++++++++++++++++++++++++++++++++++++++
5 files changed, 129 insertions(+), 14 deletions(-)
diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c
index ff630be..7a76ce6 100644
--- a/net/mac80211/ht.c
+++ b/net/mac80211/ht.c
@@ -252,8 +252,6 @@ bool ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata,
break;
}
- if (bw != sta->sta.bandwidth)
- changed = true;
sta->sta.bandwidth = bw;
sta->cur_max_bandwidth =
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 14acc21..cf8c05c 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -188,6 +188,15 @@ ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
*/
pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
chandef, 0);
+
+ if (chandef->width != NL80211_CHAN_WIDTH_20 &&
+ chandef->width != NL80211_CHAN_WIDTH_40 &&
+ sband->vht_cap.vht_supported) {
+ pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
+ sband->vht_cap.cap);
+ pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
+ chandef);
+ }
}
if (local->hw.queues >= IEEE80211_NUM_ACS)
@@ -411,6 +420,11 @@ static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
break;
+ case NL80211_CHAN_WIDTH_80:
+ case NL80211_CHAN_WIDTH_160:
+ chandef = sdata->u.ibss.chandef;
+ chandef.chan = cbss->channel;
+ break;
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
cfg80211_chandef_create(&chandef, cbss->channel,
@@ -995,6 +1009,7 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
enum ieee80211_band band = rx_status->band;
enum nl80211_bss_scan_width scan_width;
struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
+ enum nl80211_chan_width width = sdata->u.ibss.chandef.width;
bool rates_updated = false;
channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
@@ -1042,12 +1057,16 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
sta->sta.wme = true;
if (sta && elems->ht_operation && elems->ht_cap_elem &&
- sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
- sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
- sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
+ width != NL80211_CHAN_WIDTH_20_NOHT &&
+ width != NL80211_CHAN_WIDTH_5 &&
+ width != NL80211_CHAN_WIDTH_10) {
/* we both use HT */
struct ieee80211_ht_cap htcap_ie;
struct cfg80211_chan_def chandef;
+ struct ieee80211_vht_cap vhtcap_ie;
+ struct ieee80211_sta_vht_cap vht_cap;
+ const struct ieee80211_vht_operation *vht_oper;
+ enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
ieee80211_ht_oper_to_chandef(channel,
elems->ht_operation,
@@ -1055,17 +1074,36 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
- /*
- * fall back to HT20 if we don't use or use
- * the other extension channel
- */
- if (chandef.center_freq1 !=
- sdata->u.ibss.chandef.center_freq1)
- htcap_ie.cap_info &=
- cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
-
rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
sdata, sband, &htcap_ie, sta);
+
+ if (elems->vht_operation && elems->vht_cap_elem &&
+ width != NL80211_CHAN_WIDTH_20 &&
+ width != NL80211_CHAN_WIDTH_40) {
+ /* we both use VHT */
+ vht_cap = sta->sta.vht_cap;
+ vht_oper = elems->vht_operation;
+
+ ieee80211_vht_oper_to_chandef(channel, vht_oper,
+ &chandef);
+ memcpy(&vhtcap_ie, elems->vht_cap_elem,
+ sizeof(vhtcap_ie));
+ ieee80211_vht_cap_ie_to_sta_vht_cap(sdata,
+ sband,
+ &vhtcap_ie,
+ sta);
+ if (memcmp(&vht_cap, &sta->sta.vht_cap,
+ sizeof(vht_cap)))
+ rates_updated |= true;
+ }
+
+ if (bw != sta->sta.bandwidth)
+ rates_updated |= true;
+
+ if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
+ &chandef))
+ /* TODO handle incompatible chandefs */
+ WARN_ON_ONCE(1);
}
if (sta && rates_updated) {
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index b1451b3..e71ed27 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1968,6 +1968,8 @@ u8 *ieee80211_ie_build_ht_oper(u8 *pos, struct ieee80211_sta_ht_cap *ht_cap,
u16 prot_mode);
u8 *ieee80211_ie_build_vht_cap(u8 *pos, struct ieee80211_sta_vht_cap *vht_cap,
u32 cap);
+u8 *ieee80211_ie_build_vht_oper(u8 *pos, struct ieee80211_sta_vht_cap *vht_cap,
+ const struct cfg80211_chan_def *chandef);
int ieee80211_parse_bitrates(struct cfg80211_chan_def *chandef,
const struct ieee80211_supported_band *sband,
const u8 *srates, int srates_len, u32 *rates);
@@ -1983,6 +1985,9 @@ u8 *ieee80211_add_wmm_info_ie(u8 *buf, u8 qosinfo);
void ieee80211_ht_oper_to_chandef(struct ieee80211_channel *control_chan,
const struct ieee80211_ht_operation *ht_oper,
struct cfg80211_chan_def *chandef);
+void ieee80211_vht_oper_to_chandef(struct ieee80211_channel *control_chan,
+ const struct ieee80211_vht_operation *oper,
+ struct cfg80211_chan_def *chandef);
u32 ieee80211_chandef_downgrade(struct cfg80211_chan_def *c);
int __must_check
diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c
index b488e18..9875d82 100644
--- a/net/mac80211/mesh_plink.c
+++ b/net/mac80211/mesh_plink.c
@@ -382,6 +382,7 @@ static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
struct ieee80211_supported_band *sband;
u32 rates, basic_rates = 0, changed = 0;
+ enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth;
sband = local->hw.wiphy->bands[band];
rates = ieee80211_sta_get_rates(sdata, elems, band, &basic_rates);
@@ -401,6 +402,9 @@ static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata,
elems->ht_cap_elem, sta))
changed |= IEEE80211_RC_BW_CHANGED;
+ if (bw != sta->sta.bandwidth)
+ changed |= IEEE80211_RC_BW_CHANGED;
+
/* HT peer is operating 20MHz-only */
if (elems->ht_operation &&
!(elems->ht_operation->ht_param &
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 8428f4a..4522200 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -2344,6 +2344,43 @@ u8 *ieee80211_ie_build_ht_oper(u8 *pos, struct ieee80211_sta_ht_cap *ht_cap,
return pos + sizeof(struct ieee80211_ht_operation);
}
+u8 *ieee80211_ie_build_vht_oper(u8 *pos, struct ieee80211_sta_vht_cap *vht_cap,
+ const struct cfg80211_chan_def *chandef)
+{
+ struct ieee80211_vht_operation *vht_oper;
+
+ /* Build VHT Operation */
+ *pos++ = WLAN_EID_VHT_OPERATION;
+ *pos++ = sizeof(struct ieee80211_vht_operation);
+
+ vht_oper = (struct ieee80211_vht_operation *)pos;
+
+ vht_oper->center_freq_seg1_idx =
+ ieee80211_frequency_to_channel(chandef->center_freq1);
+ vht_oper->center_freq_seg2_idx = 0;
+
+ /* 1 stream, MCS0-7 as a min Basic VHT MCS rates */
+ vht_oper->basic_mcs_set = cpu_to_le16(0xfffc);
+
+ switch (chandef->width) {
+ case NL80211_CHAN_WIDTH_80:
+ vht_oper->chan_width = IEEE80211_VHT_CHANWIDTH_80MHZ;
+ break;
+ case NL80211_CHAN_WIDTH_80P80:
+ vht_oper->chan_width = IEEE80211_VHT_CHANWIDTH_80P80MHZ;
+ vht_oper->center_freq_seg2_idx =
+ ieee80211_frequency_to_channel(chandef->center_freq2);
+ break;
+ case NL80211_CHAN_WIDTH_160:
+ vht_oper->chan_width = IEEE80211_VHT_CHANWIDTH_160MHZ;
+ break;
+ default:
+ return pos;
+ }
+
+ return pos + sizeof(struct ieee80211_vht_operation);
+}
+
void ieee80211_ht_oper_to_chandef(struct ieee80211_channel *control_chan,
const struct ieee80211_ht_operation *ht_oper,
struct cfg80211_chan_def *chandef)
@@ -2373,6 +2410,39 @@ void ieee80211_ht_oper_to_chandef(struct ieee80211_channel *control_chan,
cfg80211_chandef_create(chandef, control_chan, channel_type);
}
+void ieee80211_vht_oper_to_chandef(struct ieee80211_channel *control_chan,
+ const struct ieee80211_vht_operation *oper,
+ struct cfg80211_chan_def *chandef)
+{
+ if (!oper)
+ return;
+
+ chandef->chan = control_chan;
+
+ switch (oper->chan_width) {
+ case IEEE80211_VHT_CHANWIDTH_USE_HT:
+ break;
+ case IEEE80211_VHT_CHANWIDTH_80MHZ:
+ chandef->width = NL80211_CHAN_WIDTH_80;
+ break;
+ case IEEE80211_VHT_CHANWIDTH_160MHZ:
+ chandef->width = NL80211_CHAN_WIDTH_160;
+ break;
+ case IEEE80211_VHT_CHANWIDTH_80P80MHZ:
+ chandef->width = NL80211_CHAN_WIDTH_80P80;
+ break;
+ default:
+ break;
+ }
+
+ chandef->center_freq1 =
+ ieee80211_channel_to_frequency(oper->center_freq_seg1_idx,
+ control_chan->band);
+ chandef->center_freq2 =
+ ieee80211_channel_to_frequency(oper->center_freq_seg2_idx,
+ control_chan->band);
+}
+
int ieee80211_parse_bitrates(struct cfg80211_chan_def *chandef,
const struct ieee80211_supported_band *sband,
const u8 *srates, int srates_len, u32 *rates)
--
1.9.1
In case of wide bandwidth scan all channels we have
in chandef, not only control one.
Signed-off-by: Janusz Dziedzic <[email protected]>
---
net/mac80211/ibss.c | 80 ++++++++++++++++++++++++++++++++++++++++++++--
net/mac80211/ieee80211_i.h | 3 +-
net/mac80211/scan.c | 25 +++++++++------
3 files changed, 96 insertions(+), 12 deletions(-)
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index b606b53..14acc21 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -1273,7 +1273,7 @@ static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
- NULL, scan_width);
+ NULL, 0, scan_width);
}
static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
@@ -1312,6 +1312,75 @@ static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
capability, 0, true);
}
+static unsigned ibss_setup_channels(struct wiphy *wiphy,
+ struct ieee80211_channel **channels,
+ unsigned int channels_max,
+ u32 center_freq, u32 width)
+{
+ struct ieee80211_channel *chan = NULL;
+ unsigned int n_chan = 0;
+ u32 start_freq, end_freq, freq;
+
+ if (width <= 20) {
+ start_freq = center_freq;
+ end_freq = center_freq;
+ } else {
+ start_freq = center_freq - width/2 + 10;
+ end_freq = center_freq + width/2 - 10;
+ }
+
+ for (freq = start_freq; freq <= end_freq; freq += 20) {
+ chan = ieee80211_get_channel(wiphy, freq);
+ if (!chan)
+ continue;
+ if (n_chan >= channels_max)
+ return n_chan;
+
+ channels[n_chan] = chan;
+ n_chan++;
+ }
+
+ return n_chan;
+}
+
+static unsigned int
+ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy,
+ const struct cfg80211_chan_def *chandef,
+ struct ieee80211_channel **channels,
+ unsigned int channels_max)
+{
+ unsigned int n_chan = 0;
+ u32 width, cf1, cf2 = 0;
+
+ switch (chandef->width) {
+ case NL80211_CHAN_WIDTH_40:
+ width = 40;
+ break;
+ case NL80211_CHAN_WIDTH_80P80:
+ cf2 = chandef->center_freq2;
+ case NL80211_CHAN_WIDTH_80:
+ width = 80;
+ break;
+ case NL80211_CHAN_WIDTH_160:
+ width = 160;
+ break;
+ default:
+ width = 20;
+ break;
+ }
+
+ cf1 = chandef->center_freq1;
+
+ n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width);
+
+ if (cf2)
+ n_chan += ibss_setup_channels(wiphy, &channels[n_chan],
+ channels_max - n_chan, cf2,
+ width);
+
+ return n_chan;
+}
+
/*
* This function is called with state == IEEE80211_IBSS_MLME_SEARCH
*/
@@ -1381,11 +1450,18 @@ static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
/* Selected IBSS not found in current scan results - try to scan */
if (time_after(jiffies, ifibss->last_scan_completed +
IEEE80211_SCAN_INTERVAL)) {
+ struct ieee80211_channel *channels[8];
+ unsigned int num = 0;
+
sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
+ num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy,
+ &ifibss->chandef,
+ channels,
+ ARRAY_SIZE(channels));
scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef);
ieee80211_request_ibss_scan(sdata, ifibss->ssid,
- ifibss->ssid_len, chan,
+ ifibss->ssid_len, channels, num,
scan_width);
} else {
int interval = IEEE80211_SCAN_INTERVAL;
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 3afe368..b1451b3 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1556,7 +1556,8 @@ int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata);
void ieee80211_scan_work(struct work_struct *work);
int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
const u8 *ssid, u8 ssid_len,
- struct ieee80211_channel *chan,
+ struct ieee80211_channel **channels,
+ unsigned int n_channels,
enum nl80211_bss_scan_width scan_width);
int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
struct cfg80211_scan_request *req);
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 05f0d71..7bb6a93 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -928,11 +928,12 @@ int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
const u8 *ssid, u8 ssid_len,
- struct ieee80211_channel *chan,
+ struct ieee80211_channel **channels,
+ unsigned int n_channels,
enum nl80211_bss_scan_width scan_width)
{
struct ieee80211_local *local = sdata->local;
- int ret = -EBUSY;
+ int ret = -EBUSY, i, n_ch = 0;
enum ieee80211_band band;
mutex_lock(&local->mtx);
@@ -942,9 +943,8 @@ int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
goto unlock;
/* fill internal scan request */
- if (!chan) {
- int i, max_n;
- int n_ch = 0;
+ if (!channels) {
+ int max_n;
for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
if (!local->hw.wiphy->bands[band])
@@ -969,12 +969,19 @@ int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
local->int_scan_req->n_channels = n_ch;
} else {
- if (WARN_ON_ONCE(chan->flags & (IEEE80211_CHAN_NO_IR |
- IEEE80211_CHAN_DISABLED)))
+ for (i = 0; i < n_channels; i++) {
+ if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
+ IEEE80211_CHAN_DISABLED))
+ continue;
+
+ local->int_scan_req->channels[n_ch] = channels[i];
+ n_ch++;
+ }
+
+ if (WARN_ON_ONCE(n_ch == 0))
goto unlock;
- local->int_scan_req->channels[0] = chan;
- local->int_scan_req->n_channels = 1;
+ local->int_scan_req->n_channels = n_ch;
}
local->int_scan_req->ssids = &local->scan_ssid;
--
1.9.1
On Sat, 2015-02-21 at 16:52 +0100, Janusz Dziedzic wrote:
> @@ -1055,17 +1074,36 @@ static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
>
> memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
>
> - /*
> - * fall back to HT20 if we don't use or use
> - * the other extension channel
> - */
> - if (chandef.center_freq1 !=
> - sdata->u.ibss.chandef.center_freq1)
> - htcap_ie.cap_info &=
> - cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
> -
> rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
> sdata, sband, &htcap_ie, sta);
> +
> + if (elems->vht_operation && elems->vht_cap_elem &&
> + width != NL80211_CHAN_WIDTH_20 &&
> + width != NL80211_CHAN_WIDTH_40) {
> + /* we both use VHT */
> + vht_cap = sta->sta.vht_cap;
> + vht_oper = elems->vht_operation;
> +
> + ieee80211_vht_oper_to_chandef(channel, vht_oper,
> + &chandef);
> + memcpy(&vhtcap_ie, elems->vht_cap_elem,
> + sizeof(vhtcap_ie));
> + ieee80211_vht_cap_ie_to_sta_vht_cap(sdata,
> + sband,
> + &vhtcap_ie,
> + sta);
> + if (memcmp(&vht_cap, &sta->sta.vht_cap,
> + sizeof(vht_cap)))
> + rates_updated |= true;
Some refactoring would be great, with expressions and argument lists
like this.
> + if (!
> cfg80211_chandef_compatible(&sdata->u.ibss.chandef,
> + &chandef))
> + /* TODO handle incompatible chandefs
> */
> + WARN_ON_ONCE(1);
That seems like an unaddressed TODO? I don't think you should warn on a
remote problem.
johannes
On Sat, 2015-02-21 at 16:52 +0100, Janusz Dziedzic wrote:
> Add NL80211_EXT_FEATURE_VHT_IBSS flag and VHT
> support for IBSS.
Applied.
johannes
On Sat, 2015-02-21 at 16:52 +0100, Janusz Dziedzic wrote:
> In case of wide bandwidth scan all channels we have
> in chandef, not only control one.
I think you should say why :)
> @@ -1381,11 +1450,18 @@ static void ieee80211_sta_find_ibss(struct
> ieee80211_sub_if_data *sdata)
> /* Selected IBSS not found in current scan results - try to
> scan */
> if (time_after(jiffies, ifibss->last_scan_completed +
> IEEE80211_SCAN_INTERVAL)) {
> + struct ieee80211_channel *channels[8];
> + unsigned int num = 0;
no need to initialize 'num' here.
johannes