Re: [PATCH rtw-next 1/2] wifi: rtw88: usb: Reduce control message timeout to 500 ms

[Bitterblue Smith <rtl8821cerfe2@gmail.com>]

On 08/05/2025 06:11, Ping-Ke Shih wrote:
> Bitterblue Smith <rtl8821cerfe2@gmail.com> wrote:
>> RTL8811AU stops responding during the firmware download on some systems:
>>
>> [  809.256440] rtw_8821au 5-2.1:1.0: Firmware version 42.4.0, H2C version 0
>> [  812.759142] rtw_8821au 5-2.1:1.0 wlp48s0f4u2u1: renamed from wlan0
>> [  837.315388] rtw_8821au 1-4:1.0: write register 0x1ef4 failed with -110
>> [  867.524259] rtw_8821au 1-4:1.0: write register 0x1ef8 failed with -110
>> [  868.930976] rtw_8821au 5-2.1:1.0 wlp48s0f4u2u1: entered promiscuous mode
>> [  897.730952] rtw_8821au 1-4:1.0: write register 0x1efc failed with -110
>>
>> Each write takes 30 seconds to fail because that's the timeout currently
>> used for control messages in rtw_usb_write().
>>
>> In this scenario the firmware download takes at least 2000 seconds.
>> Because this is done from the USB probe function, the long delay makes
>> other things in the system hang.
>>
>> Reduce the timeout to 500 ms. This is the value used by the official USB
>> wifi drivers from Realtek.
> 
> A question about timeout time. Is this enough for USB 2 or older?
> 

Yes, it's fine.

>>
>> Of course this only makes things hang for ~30 seconds instead of ~30
>> minutes. It doesn't fix the firmware download.
>>
>> Tested with RTL8822CU, RTL8812BU, RTL8811CU, RTL8814AU, RTL8811AU,
>> RTL8812AU, RTL8821AU, RTL8723DU.
>>
>> Cc: stable@vger.kernel.org
>> Fixes: a82dfd33d123 ("wifi: rtw88: Add common USB chip support")
>> Link: https://github.com/lwfinger/rtw88/issues/344
>> Signed-off-by: Bitterblue Smith <rtl8821cerfe2@gmail.com>
> 
> Acked-by: Ping-Ke Shih <pkshih@realtek.com>
> 
>