diff --git a/drivers/net/wireless/mediatek/mt76/testmode.c b/drivers/net/wireless/mediatek/mt76/testmode.c
index 883f59c7a7e4..7ab99efb7f9b 100644
--- a/drivers/net/wireless/mediatek/mt76/testmode.c
+++ b/drivers/net/wireless/mediatek/mt76/testmode.c
@@ -6,6 +6,7 @@ static const struct nla_policy mt76_tm_policy[NUM_MT76_TM_ATTRS] = {
 	[MT76_TM_ATTR_RESET] = { .type = NLA_FLAG },
 	[MT76_TM_ATTR_STATE] = { .type = NLA_U8 },
 	[MT76_TM_ATTR_TX_COUNT] = { .type = NLA_U32 },
+	[MT76_TM_ATTR_TX_LENGTH] = { .type = NLA_U32 },
 	[MT76_TM_ATTR_TX_RATE_MODE] = { .type = NLA_U8 },
 	[MT76_TM_ATTR_TX_RATE_NSS] = { .type = NLA_U8 },
 	[MT76_TM_ATTR_TX_RATE_IDX] = { .type = NLA_U8 },