From: Karl Beldan <karl.beldan@xxxxxxxxxxxxxxxx>
The number of VHT spatial streams (NSS) is found in:
- s8 ieee80211_tx_rate.rate.idx[6:4] (tx - filled by rate control)
- u8 ieee80211_rx_status.vht_nss (rx - filled by driver)
Tx discriminates valid rates indexes with the sign bit and encodes NSS
starting from 0 to 7 (note this matches some hw encodings e.g IWLMVM).
Rx does not have the same constraints, and encodes NSS starting from 1
to 8 (note this matches what wireshark expects in the radiotap header).
To handle ieee80211_tx_rate.rate.idx[6:4] ieee80211_rate_set_vht() and
ieee80211_rate_get_vht_nss() assume their nss parameter and return value
respectively runs from 0 to 7.
ATM, there are only 2 users of these: cfg.c:sta_set_rate_info_t() and
iwlwifi/mvm/tx.c:iwl_mvm_hwrate_to_tx_control(), but both assume nss
runs from 1 to 8.
This patch fixes this inconsistency by making ieee80211_rate_set_vht()
and ieee80211_rate_get_vht_nss() handle an nss running from 1 to 8.
Signed-off-by: Karl Beldan <karl.beldan@xxxxxxxxxxxxxxxx>
---
This might feel very verbose for such a trivial thing.
include/net/mac80211.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 0dde213..2317ca9 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -601,8 +601,8 @@ static inline void ieee80211_rate_set_vht(struct ieee80211_tx_rate *rate,
u8 mcs, u8 nss)
{
WARN_ON(mcs & ~0xF);
- WARN_ON(nss & ~0x7);
- rate->idx = (nss << 4) | mcs;
+ WARN_ON((nss - 1) & ~0x7);
+ rate->idx = ((nss - 1) << 4) | mcs;
}
static inline u8
@@ -614,7 +614,7 @@ ieee80211_rate_get_vht_mcs(const struct ieee80211_tx_rate *rate)
static inline u8
ieee80211_rate_get_vht_nss(const struct ieee80211_tx_rate *rate)
{
- return rate->idx >> 4;
+ return (rate->idx >> 4) + 1;
}
/**
--
1.8.2
--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
