Re: [PATCH] usb: add quirks for Lenovo OneLink+ Dock

From: Oliver Neukum
Date: Tue Aug 30 2022 - 10:47:48 EST


On 30.08.22 15:56, jflf_kernel@xxxxxxx wrote:

Hi,

> I agree that USB_QUIRK_RESET_RESUME seems fishy with a hub. It's pretty much the last quirk I tried, and the only one that worked. I can't say I understand what it does exactly.

Two things

1) force a reset after a resume and call reset_resume() instead of resume()
2) block autosuspend if remote wakeup is required

I suspect you are actually using the second effect. Have you
tested with "usbcore.autosuspend=-1" on the kernel command line.

The hubs themselves don't seem to reset (or at least not fully), as
there is no re-enumeration of existing children.

Probably because they do not suspend at all. Generally hubs do need
remote wakeup lest they forget the port whose activity woke the system.

> I have not experienced a single problem or side effect since using those quirks. I use a mix of USB 2.0 and 3.0 devices, some bus- and some self-powered, some permanently connected (including ethernet and audio in the hub itself) and some not.

The interesting test would be to see whether a keyboard, ethernet
or mouse can wake your system from suspend. Have you tested WOL?

Regards
Oliver