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Date: Mon, 27 May 2024 21:43:23 +0300
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Subject: Re: wifi: rtw88: 8821CU hangs after some number of power-off/on
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To: =?UTF-8?Q?Marcin_=C5=9Alusarz?= <marcin.slusarz@gmail.com>,
 linux-wireless@vger.kernel.org
Cc: =?UTF-8?Q?Marcin_=C5=9Alusarz?= <mslusarz@renau.com>
References: <20240527173454.459264-1-marcin.slusarz@gmail.com>
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From: Bitterblue Smith <rtl8821cerfe2@gmail.com>
In-Reply-To: <20240527173454.459264-1-marcin.slusarz@gmail.com>
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On 27/05/2024 20:34, Marcin Ślusarz wrote:
> From: Marcin Ślusarz <mslusarz@renau.com>
> 
> If I don't connect to any Wifi network, after around 10 minutes, the device
> hangs with endless spamming of:
> rtw_8821cu 1-1:1.2: rtw_usb_reg_sec: reg 0x4e0, usb write 1 fail, status: -71
> killing both Wifi and Bluetooth part of the device.
> 
> On arm, just leaving the wifi device unconnected kills it in up to 20 minutes.
> If I keep restarting wpa_supplicant I can trigger it within a minute.
> Looping "ifconfig wlan0 down; ifconfig wlan0 up" also triggers it within a minute.
> 
> On x86_64 system the only way I could trigger this was via ifconfig loop,
> but it took 3 hours and 20 minutes to do it.
> 
> The only thing that can "fix" the device is replugging it.
> 
> I found out that the reason for those hangs is a power-off+on sequence that's
> triggered by the above steps.
> 
> Disabling power-off for that chip "fixes" the issue. The patches below
> implement that, but I'm not seriously proposing them for merging.
> 
> Marcin Ślusarz (2):
>   wifi: rtw88: use RTW_FLAG_RUNNING for deciding whether to enter/leave
>     IPS
>   wifi: rtw88: disable power offs for 8821C
> 
>  drivers/net/wireless/realtek/rtw88/main.c | 14 ++++++++------
>  drivers/net/wireless/realtek/rtw88/ps.c   |  4 ++--
>  2 files changed, 10 insertions(+), 8 deletions(-)
> 

The first patch alone doesn't fix it?