Subject: [PATCH 1/2] mt76: mt7915: fix unused 'mode' variable

From: Arnd Bergmann <[email-masked]>
Date: Thu, 25 Feb 2021 15:59:14 +0100

From: Arnd Bergmann <[email-masked]>

clang points out a possible corner case in the mt7915_tm_set_tx_cont()
function if called with invalid arguments:

drivers/net/wireless/mediatek/mt76/mt7915/testmode.c:593:2: warning: variable 'mode' is used uninitialized whenever switch default is taken [-Wsometimes-uninitialized]
        default:
        ^~~~~~~
drivers/net/wireless/mediatek/mt76/mt7915/testmode.c:597:13: note: uninitialized use occurs here
        rateval =  mode << 6 | rate_idx;
                   ^~~~
drivers/net/wireless/mediatek/mt76/mt7915/testmode.c:506:37: note: initialize the variable 'mode' to silence this warning
        u8 rate_idx = td->tx_rate_idx, mode;
                                           ^

Change it to return an error instead of continuing with invalid data
here.

Fixes: 3f0caa3cbf94 ("mt76: mt7915: add support for continuous tx in testmode")
Signed-off-by: Arnd Bergmann <[email-masked]>
---
 drivers/net/wireless/mediatek/mt76/mt7915/testmode.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/testmode.c b/drivers/net/wireless/mediatek/mt76/mt7915/testmode.c
index 7fb2170a9561..aa629e1fb420 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/testmode.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/testmode.c
@@ -543,6 +543,7 @@ mt7915_tm_set_tx_cont(struct mt7915_phy *phy, bool en)
 		tx_cont->bw = CMD_CBW_20MHZ;
 		break;
 	default:
+		return -EINVAL;
 		break;
 	}
 
@@ -591,6 +592,7 @@ mt7915_tm_set_tx_cont(struct mt7915_phy *phy, bool en)
 		mode = MT_PHY_TYPE_HE_MU;
 		break;
 	default:
+		return -EINVAL;
 		break;
 	}
 
-- 
2.29.2