# Re: \[PATCH net,stable\] qmi\_wwan: set DTR for modems in forced USB2 mode

- From: David Miller \<davem@davemloft.net\>
- Date: 2018-09-18 02:23:47 
- List: netdev
- Page: https://ratatoskr.run/netdev/2018/09/8865133
- Thread: https://ratatoskr.run/netdev/2018/09/8865133/t.md

```text
From: Bjørn Mork <bjorn@mork.no>
Date: Mon, 17 Sep 2018 22:00:24 +0200

> Recent firmware revisions have added the ability to force
> these modems to USB2 mode, hiding their SuperSpeed
> capabilities from the host.  The driver has been using the
> SuperSpeed capability, as shown by the bcdUSB field of the
> device descriptor, to detect the need to enable the DTR
> quirk.  This method fails when the modems are forced to
> USB2 mode by the modem firmware.
> 
> Fix by unconditionally enabling the DTR quirk for the
> affected device IDs.
> 
> Reported-by: Fred Veldini <redacted>
> Reported-by: Deshu Wen <redacted>
> Signed-off-by: Bjørn Mork <bjorn@mork.no>

Applied and queued up for -stable.
```