diff --git a/drivers/net/wireless/mediatek/mt76/testmode.c b/drivers/net/wireless/mediatek/mt76/testmode.c
index 0accc71a91c9a0..4644dace9bb341 100644
--- a/drivers/net/wireless/mediatek/mt76/testmode.c
+++ b/drivers/net/wireless/mediatek/mt76/testmode.c
@@ -8,6 +8,7 @@ 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 },