nl80211: Add frequency configuration (including HT40)

This patch adds new NL80211_CMD_SET_WIPHY attributes
NL80211_ATTR_WIPHY_FREQ and NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET to allow
userspace to set the operating channel (e.g., hostapd for AP mode).

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

3 files changed, 33 insertions, 2 deletions

diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index e08c8bc..92f79d2b 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -26,8 +26,9 @@
  * @NL80211_CMD_GET_WIPHY: request information about a wiphy or dump request
  *	to get a list of all present wiphys.
  * @NL80211_CMD_SET_WIPHY: set wiphy parameters, needs %NL80211_ATTR_WIPHY or
- *	%NL80211_ATTR_IFINDEX; can be used to set %NL80211_ATTR_WIPHY_NAME
- *	and/or %NL80211_ATTR_WIPHY_TXQ_PARAMS.
+ *	%NL80211_ATTR_IFINDEX; can be used to set %NL80211_ATTR_WIPHY_NAME,
+ *	%NL80211_ATTR_WIPHY_TXQ_PARAMS, %NL80211_ATTR_WIPHY_FREQ, and/or
+ *	%NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET.
  * @NL80211_CMD_NEW_WIPHY: Newly created wiphy, response to get request
  *	or rename notification. Has attributes %NL80211_ATTR_WIPHY and
  *	%NL80211_ATTR_WIPHY_NAME.
@@ -180,6 +181,14 @@ enum nl80211_commands {
  *	/sys/class/ieee80211/<phyname>/index
  * @NL80211_ATTR_WIPHY_NAME: wiphy name (used for renaming)
  * @NL80211_ATTR_WIPHY_TXQ_PARAMS: a nested array of TX queue parameters
+ * @NL80211_ATTR_WIPHY_FREQ: frequency of the selected channel in MHz
+ * @NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET: included with NL80211_ATTR_WIPHY_FREQ
+ *	if HT20 or HT40 are allowed (i.e., 802.11n disabled if not included):
+ *	NL80211_SEC_CHAN_NO_HT = HT not allowed (i.e., same as not including
+ *		this attribute)
+ *	NL80211_SEC_CHAN_DISABLED = HT20 only
+ *	NL80211_SEC_CHAN_BELOW = secondary channel is below the primary channel
+ *	NL80211_SEC_CHAN_ABOVE = secondary channel is above the primary channel
  *
  * @NL80211_ATTR_IFINDEX: network interface index of the device to operate on
  * @NL80211_ATTR_IFNAME: network interface name
@@ -315,6 +324,8 @@ enum nl80211_attrs {
 	NL80211_ATTR_BSS_BASIC_RATES,
 
 	NL80211_ATTR_WIPHY_TXQ_PARAMS,
+	NL80211_ATTR_WIPHY_FREQ,
+	NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET,
 
 	/* add attributes here, update the policy in nl80211.c */
 
@@ -329,6 +340,8 @@ enum nl80211_attrs {
 #define NL80211_ATTR_HT_CAPABILITY NL80211_ATTR_HT_CAPABILITY
 #define NL80211_ATTR_BSS_BASIC_RATES NL80211_ATTR_BSS_BASIC_RATES
 #define NL80211_ATTR_WIPHY_TXQ_PARAMS NL80211_ATTR_WIPHY_TXQ_PARAMS
+#define NL80211_ATTR_WIPHY_FREQ NL80211_ATTR_WIPHY_FREQ
+#define NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET NL80211_ATTR_WIPHY_SEC_CHAN_OFFSET
 
 #define NL80211_MAX_SUPP_RATES			32
 #define NL80211_MAX_SUPP_REG_RULES		32
@@ -742,4 +755,10 @@ enum nl80211_txq_q {
 	NL80211_TXQ_Q_BK
 };
 
+enum nl80211_sec_chan_offset {
+	NL80211_SEC_CHAN_NO_HT /* No HT */,
+	NL80211_SEC_CHAN_DISABLED /* HT20 only */,
+	NL80211_SEC_CHAN_BELOW /* HT40- */,
+	NL80211_SEC_CHAN_ABOVE /* HT40+ */
+};
 #endif /* __LINUX_NL80211_H */
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 1d57835..53b06f6 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -392,6 +392,9 @@ struct ieee80211_txq_params {
 /* from net/wireless.h */
 struct wiphy;
 
+/* from net/ieee80211.h */
+struct ieee80211_channel;
+
 /**
  * struct cfg80211_ops - backend description for wireless configuration
  *
@@ -450,6 +453,8 @@ struct wiphy;
  * @change_bss: Modify parameters for a given BSS.
  *
  * @set_txq_params: Set TX queue parameters
+ *
+ * @set_channel: Set channel
  */
 struct cfg80211_ops {
 	int	(*add_virtual_intf)(struct wiphy *wiphy, char *name,
@@ -513,6 +518,10 @@ struct cfg80211_ops {
 
 	int	(*set_txq_params)(struct wiphy *wiphy,
 				  struct ieee80211_txq_params *params);
+
+	int	(*set_channel)(struct wiphy *wiphy,
+			       struct ieee80211_channel *chan,
+			       enum nl80211_sec_chan_offset);
 };
 
 #endif /* __NET_CFG80211_H */
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 6a1d4ea..6e823cc 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -507,6 +507,9 @@ static inline int __deprecated __IEEE80211_CONF_SHORT_SLOT_TIME(void)
 
 struct ieee80211_ht_conf {
 	bool enabled;
+	int sec_chan_offset; /* 0 = HT40 disabled; -1 = HT40 enabled, secondary
+			      * channel below primary; 1 = HT40 enabled,
+			      * secondary channel above primary */
 };
 
 /**