cfg80211/nl80211: add IBSS API

This adds IBSS API along with (preliminary) wext handlers.
The wext handlers can only do IBSS so you need to call them
from your own wext handlers if the mode is IBSS.

The nl80211 API requires
 * an SSID
 * a channel (frequency) for the case that a new IBSS
   has to be created

It optionally supports
 * a flag to fix the channel
 * a fixed BSSID

The cfg80211 code also takes care to leave the IBSS before
the netdev is set down. If wireless extensions are used, it
also caches values when the interface is down and instructs
the driver to join when the interface is set up.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/net/wireless/wext-compat.c b/net/wireless/wext-compat.c
index 6fd7bf7b448..57eaea26b67 100644
--- a/net/wireless/wext-compat.c
+++ b/net/wireless/wext-compat.c
@@ -285,3 +285,33 @@ int cfg80211_wext_siwmlme(struct net_device *dev,
 	}
 }
 EXPORT_SYMBOL(cfg80211_wext_siwmlme);
+
+
+/**
+ * cfg80211_wext_freq - get wext frequency for non-"auto"
+ * @wiphy: the wiphy
+ * @freq: the wext freq encoding
+ *
+ * Returns a channel, %NULL for auto, or an ERR_PTR for errors!
+ */
+struct ieee80211_channel *cfg80211_wext_freq(struct wiphy *wiphy,
+					     struct iw_freq *freq)
+{
+	if (freq->e == 0) {
+		if (freq->m < 0)
+			return NULL;
+		else
+			return ieee80211_get_channel(wiphy,
+				ieee80211_channel_to_frequency(freq->m));
+	} else {
+		int i, div = 1000000;
+		for (i = 0; i < freq->e; i++)
+			div /= 10;
+		if (div > 0)
+			return ieee80211_get_channel(wiphy, freq->m / div);
+		else
+			return ERR_PTR(-EINVAL);
+	}
+
+}
+EXPORT_SYMBOL(cfg80211_wext_freq);