[PATCH 6.0 0444/1073] wifi: mt76: mt7915: Fix chainmask calculation on mt7915 DBDC

Greg Kroah-Hartman
2022-12-28T15:52:33Z

From: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>

[ Upstream commit de147cc28985a2a09e5d6d179fc5ef59b22fc058 ]

mt7915 does not have a per-band number of chains unlike the other chips,
it only has a total number of chains. Yet the current code would
consider the total number as a per-band number.

For example, it would report that a 2x2 + 2x2 DBDC card have 4 chains on
each band and set chainmask to 0b1111 for the first interface and
0b11110000 for the second.

Fixes: 99ad32a4ca3a ("mt76: mt7915: add support for MT7986")
Co-developed-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/mediatek/mt76/mt7915/eeprom.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/eeprom.c b/drivers/net/wireless/mediatek/mt76/mt7915/eeprom.c
index 83bced0c0785..0bce0ce51be0 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/eeprom.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/eeprom.c
@@ -194,6 +194,7 @@ void mt7915_eeprom_parse_hw_cap(struct mt7915_dev *dev,
nss = path;
if (dev->dbdc_support) {
if (is_mt7915(&dev->mt76)) {
+ path = min_t(u8, path, 2);
nss = FIELD_GET(MT_EE_WIFI_CONF3_TX_PATH_B0,
eeprom[MT_EE_WIFI_CONF + 3]);
if (phy->band_idx)
--
2.35.1