From db9c64cf8d9d3fcbc34b09d037f266d1fc9f928c Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Fri, 9 Nov 2012 14:56:41 +0100
Subject: nl80211/cfg80211: add VHT MCS support

Add support for reporting and calculating VHT MCSes.

Note that I'm not completely sure that the bitrate
calculations are correct, nor that they can't be
simplified.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/wireless/util.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 73 insertions(+), 1 deletion(-)

(limited to 'net/wireless/util.c')

diff --git a/net/wireless/util.c b/net/wireless/util.c
index db61fe8a6b6..3cce6e48621 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -944,14 +944,86 @@ static u32 cfg80211_calculate_bitrate_60g(struct rate_info *rate)
 	return __mcs2bitrate[rate->mcs];
 }
 
+static u32 cfg80211_calculate_bitrate_vht(struct rate_info *rate)
+{
+	static const u32 base[4][10] = {
+		{   6500000,
+		   13000000,
+		   19500000,
+		   26000000,
+		   39000000,
+		   52000000,
+		   58500000,
+		   65000000,
+		   78000000,
+		   0,
+		},
+		{  13500000,
+		   27000000,
+		   40500000,
+		   54000000,
+		   81000000,
+		  108000000,
+		  121500000,
+		  135000000,
+		  162000000,
+		  180000000,
+		},
+		{  29300000,
+		   58500000,
+		   87800000,
+		  117000000,
+		  175500000,
+		  234000000,
+		  263300000,
+		  292500000,
+		  351000000,
+		  390000000,
+		},
+		{  58500000,
+		  117000000,
+		  175500000,
+		  234000000,
+		  351000000,
+		  468000000,
+		  526500000,
+		  585000000,
+		  702000000,
+		  780000000,
+		},
+	};
+	u32 bitrate;
+	int idx;
+
+	if (WARN_ON_ONCE(rate->mcs > 9))
+		return 0;
+
+	idx = rate->flags & (RATE_INFO_FLAGS_160_MHZ_WIDTH |
+			     RATE_INFO_FLAGS_80P80_MHZ_WIDTH) ? 3 :
+		  rate->flags & RATE_INFO_FLAGS_80_MHZ_WIDTH ? 2 :
+		  rate->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH ? 1 : 0;
+
+	bitrate = base[idx][rate->mcs];
+	bitrate *= rate->nss;
+
+	if (rate->flags & RATE_INFO_FLAGS_SHORT_GI)
+		bitrate = (bitrate / 9) * 10;
+
+	/* do NOT round down here */
+	return (bitrate + 50000) / 100000;
+}
+
 u32 cfg80211_calculate_bitrate(struct rate_info *rate)
 {
 	int modulation, streams, bitrate;
 
-	if (!(rate->flags & RATE_INFO_FLAGS_MCS))
+	if (!(rate->flags & RATE_INFO_FLAGS_MCS) &&
+	    !(rate->flags & RATE_INFO_FLAGS_VHT_MCS))
 		return rate->legacy;
 	if (rate->flags & RATE_INFO_FLAGS_60G)
 		return cfg80211_calculate_bitrate_60g(rate);
+	if (rate->flags & RATE_INFO_FLAGS_VHT_MCS)
+		return cfg80211_calculate_bitrate_vht(rate);
 
 	/* the formula below does only work for MCS values smaller than 32 */
 	if (WARN_ON_ONCE(rate->mcs >= 32))
-- 
cgit v1.2.2