[PATCH AUTOSEL 6.7 093/108] wifi: rtlwifi: add calculate_bit_shift()

Sasha Levin
2024-01-16T19:46:34Z

From: Su Hui <suhui@nfschina.com>

[ Upstream commit 52221dfddbbfb5b4e029bb2efe9bb7da33ec1e46 ]

There are many same functions like _rtl88e_phy_calculate_bit_shift(),
_rtl92c_phy_calculate_bit_shift() and so on. And these functions can
cause undefined bitwise shift behavior. Add calculate_bit_shift() to
replace them and fix undefined behavior in subsequent patches.

Signed-off-by: Su Hui <suhui@nfschina.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20231219065739.1895666-2-suhui@nfschina.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/realtek/rtlwifi/wifi.h | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/net/wireless/realtek/rtlwifi/wifi.h b/drivers/net/wireless/realtek/rtlwifi/wifi.h
index 31a481f43a07..5d842cc394aa 100644
--- a/drivers/net/wireless/realtek/rtlwifi/wifi.h
+++ b/drivers/net/wireless/realtek/rtlwifi/wifi.h
@@ -3069,4 +3069,11 @@ static inline struct ieee80211_sta *rtl_find_sta(struct ieee80211_hw *hw,
return ieee80211_find_sta(mac->vif, mac_addr);
}

+static inline u32 calculate_bit_shift(u32 bitmask)
+{
+ if (WARN_ON_ONCE(!bitmask))
+ return 0;
+
+ return __ffs(bitmask);
+}
#endif
--
2.43.0