cfg80211: Add a function to get the number of supported channels

Add a utility function to get the number of channels supported by
the device, and update the places in the code that need this data.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
[replace another occurrence in libertas, fix kernel-doc, fix bugs]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

4 files changed, 20 insertions, 26 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 2085712..d0afd82 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5285,12 +5285,7 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info)
 			goto unlock;
 		}
 	} else {
-		enum ieee80211_band band;
-		n_channels = 0;
-
-		for (band = 0; band < IEEE80211_NUM_BANDS; band++)
-			if (wiphy->bands[band])
-				n_channels += wiphy->bands[band]->n_channels;
+		n_channels = ieee80211_get_num_supported_channels(wiphy);
 	}
 
 	if (info->attrs[NL80211_ATTR_SCAN_SSIDS])
@@ -5498,11 +5493,7 @@ static int nl80211_start_sched_scan(struct sk_buff *skb,
 		if (!n_channels)
 			return -EINVAL;
 	} else {
-		n_channels = 0;
-
-		for (band = 0; band < IEEE80211_NUM_BANDS; band++)
-			if (wiphy->bands[band])
-				n_channels += wiphy->bands[band]->n_channels;
+		n_channels = ieee80211_get_num_supported_channels(wiphy);
 	}
 
 	if (info->attrs[NL80211_ATTR_SCAN_SSIDS])
diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index a32d52a..b528e31 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -1089,11 +1089,8 @@ int cfg80211_wext_siwscan(struct net_device *dev,
 	/* Determine number of channels, needed to allocate creq */
 	if (wreq && wreq->num_channels)
 		n_channels = wreq->num_channels;
-	else {
-		for (band = 0; band < IEEE80211_NUM_BANDS; band++)
-			if (wiphy->bands[band])
-				n_channels += wiphy->bands[band]->n_channels;
-	}
+	else
+		n_channels = ieee80211_get_num_supported_channels(wiphy);
 
 	creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
 		       n_channels * sizeof(void *),
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index 3f64202..c854f1c 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -70,18 +70,11 @@ static int cfg80211_conn_scan(struct wireless_dev *wdev)
 	if (rdev->scan_req)
 		return -EBUSY;
 
-	if (wdev->conn->params.channel) {
+	if (wdev->conn->params.channel)
 		n_channels = 1;
-	} else {
-		enum ieee80211_band band;
-		n_channels = 0;
+	else
+		n_channels = ieee80211_get_num_supported_channels(wdev->wiphy);
 
-		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
-			if (!wdev->wiphy->bands[band])
-				continue;
-			n_channels += wdev->wiphy->bands[band]->n_channels;
-		}
-	}
 	request = kzalloc(sizeof(*request) + sizeof(request->ssids[0]) +
 			  sizeof(request->channels[0]) * n_channels,
 			  GFP_KERNEL);
diff --git a/net/wireless/util.c b/net/wireless/util.c
index 329b0ef..d39c371 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -1481,6 +1481,19 @@ int ieee80211_get_ratemask(struct ieee80211_supported_band *sband,
 	return 0;
 }
 
+unsigned int ieee80211_get_num_supported_channels(struct wiphy *wiphy)
+{
+	enum ieee80211_band band;
+	unsigned int n_channels = 0;
+
+	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
+		if (wiphy->bands[band])
+			n_channels += wiphy->bands[band]->n_channels;
+
+	return n_channels;
+}
+EXPORT_SYMBOL(ieee80211_get_num_supported_channels);
+
 /* See IEEE 802.1H for LLC/SNAP encapsulation/decapsulation */
 /* Ethernet-II snap header (RFC1042 for most EtherTypes) */
 const unsigned char rfc1042_header[] __aligned(2) =