Re: [PATCH] usb: gadget: configfs: Add lpm_Ux_disable

From: Claus H. Stovgaard
Date: Tue May 07 2019 - 05:38:05 EST


On Tue, 2019-05-07 at 11:09 +0200, Claus H. Stovgaard wrote:
> When combining dwc3 with an redriver for a USB Type-C device
> solution, it
> sometimes have problems with leaving U1/U2 for certain hosts,
> resulting in
> link training errors and reconnects. This create an interface via
> configfs for disabling U1/U2, enabling a workaround for devices based
> on
> dwc3.
>

Sorry messed up a bit with a missing cover letter.
This feature relates to Anurag patch [1] and a thread [2] from earlierÂ

Where Anurags patch focus on setting U1/U2 latency in the BOS
descriptor from the devicetree, this patch focuses on having a configfs
interface for forcing the UDC (here the dwc3) to not enable U1/U2 and
reject the SET_SEL(U1/U2).

Looking forward to input.

[1]Âhttps://www.spinics.net/lists/linux-usb/msg179732.html
[2]Âhttps://www.spinics.net/lists/linux-usb/msg179393.html