From be8eb8ab3ee42aa66930aea827bdcb05a2172276 Mon Sep 17 00:00:00 2001
From: Jouni Malinen <j@w1.fi>
Date: Sun, 29 Nov 2009 12:21:26 +0200
Subject: [PATCH] Fix AP mode HT Capabilities IE to use A-MPDU Parameters from
 the driver

Instead of using hardcoded maximum A-MPDU length of 64 kB and no
restrictions on minimum MPDU Start Spacing, use the correct values
reported by the driver.
---
 hostapd/ieee802_11.c         |  7 +------
 src/drivers/driver.h         |  1 +
 src/drivers/driver_nl80211.c | 12 ++++++++++++
 3 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/hostapd/ieee802_11.c b/hostapd/ieee802_11.c
index acd052eec..eec5e65ad 100644
--- a/hostapd/ieee802_11.c
+++ b/hostapd/ieee802_11.c
@@ -116,12 +116,7 @@ u8 * hostapd_eid_ht_capabilities(struct hostapd_data *hapd, u8 *eid)
 	cap = (struct ieee80211_ht_capabilities *) pos;
 	os_memset(cap, 0, sizeof(*cap));
 	cap->ht_capabilities_info = host_to_le16(hapd->iconf->ht_capab);
-
-	/* FIX: from driver */
-	SET_2BIT_U8(&cap->a_mpdu_params,
-		    MAC_HT_PARAM_INFO_MAX_RX_AMPDU_FACTOR_OFFSET,
-		    MAX_RX_AMPDU_FACTOR_64KB);
-
+	cap->a_mpdu_params = hapd->iface->current_mode->a_mpdu_params;
 	os_memcpy(cap->supported_mcs_set, hapd->iface->current_mode->mcs_set,
 		  16);
 
diff --git a/src/drivers/driver.h b/src/drivers/driver.h
index 9c6c10859..3fd8145bb 100644
--- a/src/drivers/driver.h
+++ b/src/drivers/driver.h
@@ -52,6 +52,7 @@ struct hostapd_hw_modes {
 	struct hostapd_rate_data *rates;
 	u16 ht_capab;
 	u8 mcs_set[16];
+	u8 a_mpdu_params;
 };
 
 
diff --git a/src/drivers/driver_nl80211.c b/src/drivers/driver_nl80211.c
index ad279a19d..466e460a8 100644
--- a/src/drivers/driver_nl80211.c
+++ b/src/drivers/driver_nl80211.c
@@ -2186,6 +2186,18 @@ static int phy_info_handler(struct nl_msg *msg, void *arg)
 				tb_band[NL80211_BAND_ATTR_HT_CAPA]);
 		}
 
+		if (tb_band[NL80211_BAND_ATTR_HT_AMPDU_FACTOR]) {
+			mode->a_mpdu_params |= nla_get_u8(
+				tb_band[NL80211_BAND_ATTR_HT_AMPDU_FACTOR]) &
+				0x03;
+		}
+
+		if (tb_band[NL80211_BAND_ATTR_HT_AMPDU_DENSITY]) {
+			mode->a_mpdu_params |= nla_get_u8(
+				tb_band[NL80211_BAND_ATTR_HT_AMPDU_DENSITY]) <<
+				2;
+		}
+
 		if (tb_band[NL80211_BAND_ATTR_HT_MCS_SET] &&
 		    nla_len(tb_band[NL80211_BAND_ATTR_HT_MCS_SET])) {
 			u8 *mcs;