Re: [PATCH] USB: storage: Ignore driver CD mode for Realtek multi-mode Wi-Fi dongles

On Thu, Aug 14, 2025 at 12:24:15AM +0800, Zenm Chen wrote:

Many Realtek USB Wi-Fi dongles released in recent years have two modes: one is driver CD mode which has Windows driver onboard, another one is Wi-Fi mode. Add the US_FL_IGNORE_DEVICE quirk for these multi-mode devices. Otherwise, usb_modeswitch may fail to switch them to Wi-Fi mode.

There are several other entries like this already in the unusual_devs.h file. But I wonder if we really still need them. Shouldn't the usb_modeswitch program be smart enough by now to know how to handle these things?

In theory, someone might want to access the Windows driver on the emulated CD. With this quirk, they wouldn't be able to.

Alan Stern