cfg80211: add support for setting the ad-hoc multicast rate

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/linux/nl80211.h

@@ -826,6 +826,8 @@ enum nl80211_commands {
  *	the hardware should not be configured to receive on this antenna.
  *	For a more detailed descripton see @NL80211_ATTR_WIPHY_ANTENNA_TX.
  *
+ * @NL80211_ATTR_MCAST_RATE: Multicast tx rate (in 100 kbps) for IBSS
+ *
  * @NL80211_ATTR_MAX: highest attribute number currently defined
  * @__NL80211_ATTR_AFTER_LAST: internal use
  */
@@ -998,6 +1000,8 @@ enum nl80211_attrs {
 	NL80211_ATTR_WIPHY_ANTENNA_TX,
 	NL80211_ATTR_WIPHY_ANTENNA_RX,
 
+	NL80211_ATTR_MCAST_RATE,
+
 	/* add attributes here, update the policy in nl80211.c */
 
 	__NL80211_ATTR_AFTER_LAST,

include/net/cfg80211.h

@@ -923,6 +923,7 @@ struct cfg80211_disassoc_request {
  * @privacy: this is a protected network, keys will be configured
  *	after joining
  * @basic_rates: bitmap of basic rates to use when creating the IBSS
+ * @mcast_rate: multicast tx rate (in 100 kbps)
  */
 struct cfg80211_ibss_params {
 	u8 *ssid;
@@ -934,6 +935,7 @@ struct cfg80211_ibss_params {
 	u32 basic_rates;
 	bool channel_fixed;
 	bool privacy;
+	int mcast_rate;
 };
 
 /**

net/wireless/nl80211.c

@@ -171,6 +171,8 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
 
 	[NL80211_ATTR_WIPHY_ANTENNA_TX] = { .type = NLA_U32 },
 	[NL80211_ATTR_WIPHY_ANTENNA_RX] = { .type = NLA_U32 },
+
+	[NL80211_ATTR_MCAST_RATE] = { .type = NLA_U32 },
 };
 
 /* policy for the key attributes */
@@ -3681,6 +3683,9 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info)
 				return -EINVAL;
 		}
 	}
+	if (info->attrs[NL80211_ATTR_MCAST_RATE])
+		ibss.mcast_rate =
+			nla_get_u32(info->attrs[NL80211_ATTR_MCAST_RATE]);
 
 	if (ibss.privacy && info->attrs[NL80211_ATTR_KEYS]) {
 		connkeys = nl80211_parse_connkeys(rdev,