On 02/01/2024 02:45, Ping-Ke Shih wrote:
>
>
>> -----Original Message-----
>> From: Bitterblue Smith <rtl8821cerfe2@xxxxxxxxx>
>> Sent: Monday, January 1, 2024 6:19 AM
>> To: linux-wireless@xxxxxxxxxxxxxxx
>> Cc: Jes Sorensen <Jes.Sorensen@xxxxxxxxx>; Ping-Ke Shih <pkshih@xxxxxxxxxxx>
>> Subject: [PATCH] wifi: rtl8xxxu: Fix off by one initial RTS rate
>>
>> rtl8xxxu_set_basic_rates() sets the wrong initial RTS rate. It sets the
>> next higher rate than the one it should set, e.g. 36M instead of 24M.
>>
>> The while loop is supposed to find the index of the most significant
>> bit which is 1.
>>
>> Signed-off-by: Bitterblue Smith <rtl8821cerfe2@xxxxxxxxx>
>> ---
>> drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> index 180907319e8c..b9f3382bd67c 100644
>> --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
>> @@ -4839,7 +4839,7 @@ static void rtl8xxxu_set_basic_rates(struct rtl8xxxu_priv *priv, u32 rate_cfg)
>>
>> dev_dbg(&priv->udev->dev, "%s: rates %08x\n", __func__, rate_cfg);
>>
>> - while (rate_cfg) {
>> + while (rate_cfg > 1) {
>> rate_cfg = (rate_cfg >> 1);
>> rate_idx++;
>> }
>
> How about using __fls()?
>
> if (rate_cfg)
> rate_idx = __fls(rate_cfg);
>
Yes, that's nicer.
