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.
Change-Id: Id4c132850a85ff59f0fc16396763ed717689bec0
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Git-commit: db9c64cf8d9d3fcbc34b09d037f266d1fc9f928c
Git-repo:
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Sameer Thalappil <sameert@codeaurora.org>
diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h
index 18a49b6..a1e1561 100644
--- a/include/linux/nl80211.h
+++ b/include/linux/nl80211.h
@@ -1847,9 +1847,14 @@
* @__NL80211_RATE_INFO_INVALID: attribute number 0 is reserved
* @NL80211_RATE_INFO_BITRATE: total bitrate (u16, 100kbit/s)
* @NL80211_RATE_INFO_MCS: mcs index for 802.11n (u8)
- * @NL80211_RATE_INFO_40_MHZ_WIDTH: 40 Mhz dualchannel bitrate
+ * @NL80211_RATE_INFO_40_MHZ_WIDTH: 40 MHz dualchannel bitrate
* @NL80211_RATE_INFO_SHORT_GI: 400ns guard interval
* @NL80211_RATE_INFO_MAX: highest rate_info number currently defined
+ * @NL80211_RATE_INFO_VHT_MCS: MCS index for VHT (u8)
+ * @NL80211_RATE_INFO_VHT_NSS: number of streams in VHT (u8)
+ * @NL80211_RATE_INFO_80_MHZ_WIDTH: 80 MHz VHT rate
+ * @NL80211_RATE_INFO_80P80_MHZ_WIDTH: 80+80 MHz VHT rate
+ * @NL80211_RATE_INFO_160_MHZ_WIDTH: 160 MHz VHT rate
* @__NL80211_RATE_INFO_AFTER_LAST: internal use
*/
enum nl80211_rate_info {
@@ -1858,6 +1863,11 @@
NL80211_RATE_INFO_MCS,
NL80211_RATE_INFO_40_MHZ_WIDTH,
NL80211_RATE_INFO_SHORT_GI,
+ NL80211_RATE_INFO_VHT_MCS,
+ NL80211_RATE_INFO_VHT_NSS,
+ NL80211_RATE_INFO_80_MHZ_WIDTH,
+ NL80211_RATE_INFO_80P80_MHZ_WIDTH,
+ NL80211_RATE_INFO_160_MHZ_WIDTH,
/* keep last */
__NL80211_RATE_INFO_AFTER_LAST,
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 8b926d6..efe817b 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -578,14 +578,24 @@
* Used by the driver to indicate the specific rate transmission
* type for 802.11n transmissions.
*
- * @RATE_INFO_FLAGS_MCS: @tx_bitrate_mcs filled
- * @RATE_INFO_FLAGS_40_MHZ_WIDTH: 40 Mhz width transmission
+ * @RATE_INFO_FLAGS_MCS: mcs field filled with HT MCS
+ * @RATE_INFO_FLAGS_VHT_MCS: mcs field filled with VHT MCS
+ * @RATE_INFO_FLAGS_40_MHZ_WIDTH: 40 MHz width transmission
+ * @RATE_INFO_FLAGS_80_MHZ_WIDTH: 80 MHz width transmission
+ * @RATE_INFO_FLAGS_80P80_MHZ_WIDTH: 80+80 MHz width transmission
+ * @RATE_INFO_FLAGS_160_MHZ_WIDTH: 160 MHz width transmission
* @RATE_INFO_FLAGS_SHORT_GI: 400ns guard interval
+ * @RATE_INFO_FLAGS_60G: 60GHz MCS
*/
enum rate_info_flags {
- RATE_INFO_FLAGS_MCS = 1<<0,
- RATE_INFO_FLAGS_40_MHZ_WIDTH = 1<<1,
- RATE_INFO_FLAGS_SHORT_GI = 1<<2,
+ RATE_INFO_FLAGS_MCS = BIT(0),
+ RATE_INFO_FLAGS_VHT_MCS = BIT(1),
+ RATE_INFO_FLAGS_40_MHZ_WIDTH = BIT(2),
+ RATE_INFO_FLAGS_80_MHZ_WIDTH = BIT(3),
+ RATE_INFO_FLAGS_80P80_MHZ_WIDTH = BIT(4),
+ RATE_INFO_FLAGS_160_MHZ_WIDTH = BIT(5),
+ RATE_INFO_FLAGS_SHORT_GI = BIT(6),
+ RATE_INFO_FLAGS_60G = BIT(7),
};
/**
@@ -596,11 +606,13 @@
* @flags: bitflag of flags from &enum rate_info_flags
* @mcs: mcs index if struct describes a 802.11n bitrate
* @legacy: bitrate in 100kbit/s for 802.11abg
+ * @nss: number of streams (VHT only)
*/
struct rate_info {
u8 flags;
u8 mcs;
u16 legacy;
+ u8 nss;
};
/**
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 2e4acce..72c9a89 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2397,25 +2397,46 @@
rate = nla_nest_start(msg, attr);
if (!rate)
- goto nla_put_failure;
+ return false;
/* cfg80211_calculate_bitrate will return 0 for mcs >= 32 */
bitrate = cfg80211_calculate_bitrate(info);
if (bitrate > 0)
- NLA_PUT_U16(msg, NL80211_RATE_INFO_BITRATE, bitrate);
+ nla_put_u16(msg, NL80211_RATE_INFO_BITRATE, bitrate);
- if (info->flags & RATE_INFO_FLAGS_MCS)
- NLA_PUT_U8(msg, NL80211_RATE_INFO_MCS, info->mcs);
- if (info->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH)
- NLA_PUT_FLAG(msg, NL80211_RATE_INFO_40_MHZ_WIDTH);
- if (info->flags & RATE_INFO_FLAGS_SHORT_GI)
- NLA_PUT_FLAG(msg, NL80211_RATE_INFO_SHORT_GI);
+ if (info->flags & RATE_INFO_FLAGS_MCS) {
+ if (nla_put_u8(msg, NL80211_RATE_INFO_MCS, info->mcs))
+ return false;
+ if (info->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH &&
+ nla_put_flag(msg, NL80211_RATE_INFO_40_MHZ_WIDTH))
+ return false;
+ if (info->flags & RATE_INFO_FLAGS_SHORT_GI &&
+ nla_put_flag(msg, NL80211_RATE_INFO_SHORT_GI))
+ return false;
+ } else if (info->flags & RATE_INFO_FLAGS_VHT_MCS) {
+ if (nla_put_u8(msg, NL80211_RATE_INFO_VHT_MCS, info->mcs))
+ return false;
+ if (nla_put_u8(msg, NL80211_RATE_INFO_VHT_NSS, info->nss))
+ return false;
+ if (info->flags & RATE_INFO_FLAGS_40_MHZ_WIDTH &&
+ nla_put_flag(msg, NL80211_RATE_INFO_40_MHZ_WIDTH))
+ return false;
+ if (info->flags & RATE_INFO_FLAGS_80_MHZ_WIDTH &&
+ nla_put_flag(msg, NL80211_RATE_INFO_80_MHZ_WIDTH))
+ return false;
+ if (info->flags & RATE_INFO_FLAGS_80P80_MHZ_WIDTH &&
+ nla_put_flag(msg, NL80211_RATE_INFO_80P80_MHZ_WIDTH))
+ return false;
+ if (info->flags & RATE_INFO_FLAGS_160_MHZ_WIDTH &&
+ nla_put_flag(msg, NL80211_RATE_INFO_160_MHZ_WIDTH))
+ return false;
+ if (info->flags & RATE_INFO_FLAGS_SHORT_GI &&
+ nla_put_flag(msg, NL80211_RATE_INFO_SHORT_GI))
+ return false;
+ }
nla_nest_end(msg, rate);
return true;
-
-nla_put_failure:
- return false;
}
static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
diff --git a/net/wireless/util.c b/net/wireless/util.c
index a448b80..7dcb067 100644
--- a/net/wireless/util.c
+++ b/net/wireless/util.c
@@ -876,13 +876,86 @@
return err;
}
+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;
+}
+
u16 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_VHT_MCS)
+ return cfg80211_calculate_bitrate_vht(rate);
+
/* the formula below does only work for MCS values smaller than 32 */
if (rate->mcs >= 32)
return 0;