ath9k: fix transmitting to stations in dynamic SMPS mode

When transmitting to a receiver in dynamic SMPS mode, all transmissions that
use multiple spatial streams need to be sent using CTS-to-self or RTS/CTS to
give the receiver's extra chains some time to wake up.
This fixes the tx rate getting stuck at <= MCS7 for some clients, especially
Intel ones, which make aggressive use of SMPS.

Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/package/kernel/mac80211/patches/ath/560-ath9k-fix-transmitting-to-stations-in-dynamic-SMPS-m.patch b/package/kernel/mac80211/patches/ath/560-ath9k-fix-transmitting-to-stations-in-dynamic-SMPS-m.patch
new file mode 100644 (file)
index 0000000..68f3a31
--- /dev/null
+++ b/package/kernel/mac80211/patches/ath/560-ath9k-fix-transmitting-to-stations-in-dynamic-SMPS-m.patch
@@ -0,0 +1,49 @@
+From: Felix Fietkau <nbd@nbd.name>
+Date: Sun, 14 Feb 2021 19:45:50 +0100
+Subject: [PATCH] ath9k: fix transmitting to stations in dynamic SMPS mode
+
+When transmitting to a receiver in dynamic SMPS mode, all transmissions that
+use multiple spatial streams need to be sent using CTS-to-self or RTS/CTS to
+give the receiver's extra chains some time to wake up.
+This fixes the tx rate getting stuck at <= MCS7 for some clients, especially
+Intel ones, which make aggressive use of SMPS.
+
+Cc: stable@vger.kernel.org
+Reported-by: Martin Kennedy <hurricos@gmail.com>
+Signed-off-by: Felix Fietkau <nbd@nbd.name>
+---
+
+--- a/drivers/net/wireless/ath/ath9k/ath9k.h
++++ b/drivers/net/wireless/ath/ath9k/ath9k.h
+@@ -179,7 +179,8 @@ struct ath_frame_info {
+       s8 txq;
+       u8 keyix;
+       u8 rtscts_rate;
+-      u8 retries : 7;
++      u8 retries : 6;
++      u8 dyn_smps : 1;
+       u8 baw_tracked : 1;
+       u8 tx_power;
+       enum ath9k_key_type keytype:2;
+--- a/drivers/net/wireless/ath/ath9k/xmit.c
++++ b/drivers/net/wireless/ath/ath9k/xmit.c
+@@ -1271,6 +1271,11 @@ static void ath_buf_set_rate(struct ath_
+                                is_40, is_sgi, is_sp);
+                       if (rix < 8 && (tx_info->flags & IEEE80211_TX_CTL_STBC))
+                               info->rates[i].RateFlags |= ATH9K_RATESERIES_STBC;
++                      if (rix >= 8 && fi->dyn_smps) {
++                              info->rates[i].RateFlags |=
++                                      ATH9K_RATESERIES_RTS_CTS;
++                              info->flags |= ATH9K_TXDESC_CTSENA;
++                      }
+ 
+                       info->txpower[i] = ath_get_rate_txpower(sc, bf, rix,
+                                                               is_40, false);
+@@ -2114,6 +2119,7 @@ static void setup_frame_info(struct ieee
+               fi->keyix = an->ps_key;
+       else
+               fi->keyix = ATH9K_TXKEYIX_INVALID;
++      fi->dyn_smps = sta && sta->smps_mode == IEEE80211_SMPS_DYNAMIC;
+       fi->keytype = keytype;
+       fi->framelen = framelen;
+       fi->tx_power = txpower;