From: Deren Wu <deren.wu@mediatek.com>
Date: Wed, 10 May 2023 06:51:13 +0000 (+0800)
Subject: wifi: mt76: mt7921: do not support one stream on secondary antenna only
X-Git-Tag: v6.4.15~15
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=046378bdf9de00a1c61000c9b7514e59e36db445;p=thirdparty%2Fkernel%2Fstable.git

wifi: mt76: mt7921: do not support one stream on secondary antenna only

commit d616d3680264beb9a9d2c4fc681064b06f447eeb upstream.

mt7921 support following antenna combiantions only.
* primary + secondary (2x2)
* primary only        (1x1)

Since we cannot work on secondary antenna only, return error if the
antenna bitmap is 0x2 in .set_antenna().

For example:
iw phy0 set antenna 3 3 /* valid */
iw phy0 set antenna 1 1 /* valid */
iw phy0 set antenna 2 2 /* invalid */

Cc: stable@vger.kernel.org
Fixes: e0f9fdda81bd ("mt76: mt7921: add ieee80211_ops")
Suggested-by: Knox Chiou <knoxchiou@google.com>
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/main.c b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
index 3b6adb29cbef1..0e3ada1e008cd 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/main.c
@@ -1363,7 +1363,7 @@ mt7921_set_antenna(struct ieee80211_hw *hw, u32 tx_ant, u32 rx_ant)
 		return -EINVAL;
 
 	if ((BIT(hweight8(tx_ant)) - 1) != tx_ant)
-		tx_ant = BIT(ffs(tx_ant) - 1) - 1;
+		return -EINVAL;
 
 	mt7921_mutex_acquire(dev);