Re: Strange problem with USB device

From: Alan Stern
Date: Thu Jun 10 2021 - 22:13:09 EST


On Fri, Jun 11, 2021 at 03:08:16AM +0300, Ibrahim Erturk wrote:
> Hi,
>
> I've already attached logs and a snapshot from the device manager on
> the windows side into the bug report. Hope this helps.

Yes, it does help. Although the information in those reports is somewhat
disorganized, it clearly shows there is only one USB host controller in the
system, and that is the one Linux detects. So my impression that we weren't
finding the host controller was wrong.

Back to my earlier guess: The Realtek board has to be told to do something in
order to make the Bluetooth device start working, such as turning on a power
source. (And perhaps that is what the RealTek people were talking about when
they suggested the problem could be in the rtw8822 power-up sequence.) Whatever
it is, the rtw8822 driver isn't doing it.

This means it's still a PCI problem.

Alan Stern

PS: Larry, the discrepancy between Windows reporting an Intel USB hub and Linux
reporting two Linux Foundation hubs isn't real -- or at least, it's what should
be expected. I can explain in more detail if you're curious, but you don't need
to worry about it.