[MAC80211]: improved short preamble handling

Similarly to CTS protection, whether short preambles are used for 802.11b
transmissions should be a per-subif setting, not device global.

For STAs, this patch makes short preamble handling automatic based on the ERP
IE. For APs, hostapd still uses the prism ioctls, but the write ioctl has been
restricted to AP-only subifs.

ieee80211_txrx_data.short_preamble (an unused field) was removed.

Unfortunately, some API changes were required for the following functions:
 - ieee80211_generic_frame_duration
 - ieee80211_rts_duration
 - ieee80211_ctstoself_duration
 - ieee80211_rts_get
 - ieee80211_ctstoself_get
Affected drivers were updated accordingly.

Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/net/wireless/rtl8187_dev.c b/drivers/net/wireless/rtl8187_dev.c
index e61c6d5ba1a9..73f1ebc7eec7 100644
--- a/drivers/net/wireless/rtl8187_dev.c
+++ b/drivers/net/wireless/rtl8187_dev.c
@@ -96,7 +96,7 @@ static int rtl8187_tx(struct ieee80211_hw *dev, struct sk_buff *skb,
         if (control->flags & IEEE80211_TXCTL_USE_RTS_CTS) {
                 tmp |= RTL8187_TX_FLAG_RTS;
                 hdr->rts_duration =
-                        ieee80211_rts_duration(dev, skb->len, control);
+                        ieee80211_rts_duration(dev, priv->if_id, skb->len, control);
         }
         if (control->flags & IEEE80211_TXCTL_USE_CTS_PROTECT)
                 tmp |= RTL8187_TX_FLAG_CTS;
@@ -510,6 +510,8 @@ static int rtl8187_config_interface(struct ieee80211_hw *dev, int if_id,
         struct rtl8187_priv *priv = dev->priv;
         int i;
 
+        priv->if_id = if_id;
+
         for (i = 0; i < ETH_ALEN; i++)
                 rtl818x_iowrite8(priv, &priv->map->BSSID[i], conf->bssid[i]);