RE: [PATCH] wifi: rtl8xxxu: fixing transmisison failure for rtl8192eu

From: Ping-Ke Shih
Date: Tue Dec 20 2022 - 00:45:25 EST




> -----Original Message-----
> From: Jun ASAKA <JunASAKA@xxxxxxxxxxxxx>
> Sent: Saturday, December 17, 2022 11:07 AM
> To: Jes.Sorensen@xxxxxxxxx
> Cc: kvalo@xxxxxxxxxx; davem@xxxxxxxxxxxxx; edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; pabeni@xxxxxxxxxx;
> linux-wireless@xxxxxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Jun ASAKA
> <JunASAKA@xxxxxxxxxxxxx>
> Subject: [PATCH] wifi: rtl8xxxu: fixing transmisison failure for rtl8192eu
>
> Fixing transmission failure which results in
> "authentication with ... timed out". This can be
> fixed by disable the REG_TXPAUSE.
>
> Signed-off-by: Jun ASAKA <JunASAKA@xxxxxxxxxxxxx>
> ---
> drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c
> b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c
> index a7d76693c02d..9d0ed6760cb6 100644
> --- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c
> +++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_8192e.c
> @@ -1744,6 +1744,11 @@ static void rtl8192e_enable_rf(struct rtl8xxxu_priv *priv)
> val8 = rtl8xxxu_read8(priv, REG_PAD_CTRL1);
> val8 &= ~BIT(0);
> rtl8xxxu_write8(priv, REG_PAD_CTRL1, val8);
> +
> + /*
> + * Fix transmission failure of rtl8192e.
> + */
> + rtl8xxxu_write8(priv, REG_TXPAUSE, 0x00);

I trace when rtl8xxxu set REG_TXPAUSE=0xff that will stop TX.
The occasions include RF calibration, LPS mode (called by power off), and
going to stop. So, I think RF calibration does TX pause but not restore
settings after calibration, and causes TX stuck. As the flow I traced,
this patch looks reasonable. But, I wonder why other people don't meet
this problem.

Reviewed-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx>

> }
>
> static s8 rtl8192e_cck_rssi(struct rtl8xxxu_priv *priv, u8 cck_agc_rpt)
> --
> 2.31.1