From: Colin Ian King colin.king@canonical.com
[ Upstream commit 87fce88658ba047ae62e83497d3f3c5dc22fa6f9 ]
Currently the expression ~nic_conf1 is always true because nic_conf1 is a u16 and according to 6.5.3.3 of the C standard the ~ operator promotes the u16 to an integer before flipping all the bits. Thus the top 16 bits of the integer result are all set so the expression is always true. If the intention was to flip all the bits of nic_conf1 then casting the integer result back to a u16 is a suitabel fix.
Interestingly static analyzers seem to thing a bitwise ! should be used instead of ~ for this scenario, so I think the original intent of the expression may need some extra consideration.
Addresses-Coverity: ("Logical vs. bitwise operator") Fixes: c869f77d6abb ("add mt7601u driver") Signed-off-by: Colin Ian King colin.king@canonical.com Acked-by: Jakub Kicinski kubakici@wp.pl Signed-off-by: Kalle Valo kvalo@codeaurora.org Link: https://lore.kernel.org/r/20210225183241.1002129-1-colin.king@canonical.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/mediatek/mt7601u/eeprom.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/wireless/mediatek/mt7601u/eeprom.c b/drivers/net/wireless/mediatek/mt7601u/eeprom.c index c868582c5d22..aa3b64902cf9 100644 --- a/drivers/net/wireless/mediatek/mt7601u/eeprom.c +++ b/drivers/net/wireless/mediatek/mt7601u/eeprom.c @@ -99,7 +99,7 @@ mt7601u_has_tssi(struct mt7601u_dev *dev, u8 *eeprom) { u16 nic_conf1 = get_unaligned_le16(eeprom + MT_EE_NIC_CONF_1);
- return ~nic_conf1 && (nic_conf1 & MT_EE_NIC_CONF_1_TX_ALC_EN); + return (u16)~nic_conf1 && (nic_conf1 & MT_EE_NIC_CONF_1_TX_ALC_EN); }
static void