Return-path: Received: from he.sipsolutions.net ([78.46.109.217]:33221 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751162Ab0DSGAV (ORCPT ); Mon, 19 Apr 2010 02:00:21 -0400 Subject: Re: [PATCH 7/9] mac80211: add flags for STBC (Space-Time Block Coding) From: Johannes Berg To: Felix Fietkau Cc: linux-wireless@vger.kernel.org, linville@tuxdriver.com, lrodriguez@atheros.com In-Reply-To: <4BCB2DB3.3020700@openwrt.org> References: <1271602602-8538-1-git-send-email-nbd@openwrt.org> <1271602602-8538-2-git-send-email-nbd@openwrt.org> <1271602602-8538-3-git-send-email-nbd@openwrt.org> <1271602602-8538-4-git-send-email-nbd@openwrt.org> <1271602602-8538-5-git-send-email-nbd@openwrt.org> <1271602602-8538-6-git-send-email-nbd@openwrt.org> <1271602602-8538-7-git-send-email-nbd@openwrt.org> <1271606009.3873.0.camel@jlt3.sipsolutions.net> <4BCB2DB3.3020700@openwrt.org> Content-Type: text/plain; charset="UTF-8" Date: Mon, 19 Apr 2010 07:57:57 +0200 Message-ID: <1271656677.3873.5.camel@jlt3.sipsolutions.net> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Sun, 2010-04-18 at 18:05 +0200, Felix Fietkau wrote: > >> + * @IEEE80211_TX_CTL_STBC: tells the driver to use Space-Time Block Coding > >> + * (STBC) for this frame. > >> */ > >> enum mac80211_tx_control_flags { > >> IEEE80211_TX_CTL_REQ_TX_STATUS = BIT(0), > >> @@ -299,6 +301,7 @@ enum mac80211_tx_control_flags { > >> IEEE80211_TX_INTFL_HAS_RADIOTAP = BIT(20), > >> IEEE80211_TX_INTFL_NL80211_FRAME_TX = BIT(21), > >> IEEE80211_TX_CTL_LDPC = BIT(22), > >> + IEEE80211_TX_CTL_STBC = BIT(23), > > > > What if the # of streams is different? That doesn't look sufficient. > Hm, you're right. I initially thought the combination of the MCS index > and the STBC flag would be enough, but there are still some corner cases. Hm actually I guess that should be sufficient? What corner case are you thinking of? johannes