Re: [PATCH 1/2] usb: gadget: restore tristate-choice for legacy gadgets

From: Bart Van Assche
Date: Mon Dec 11 2017 - 11:09:34 EST


On Mon, 2017-12-11 at 12:30 +0100, Arnd Bergmann wrote:
> One patch that was meant as a cleanup apparently did more than it intended,
> allowing all combinations of legacy gadget drivers to be built into the
> kernel, and leaving an empty 'choice' statement behind:
>
> drivers/usb/gadget/Kconfig:487:warning: choice default symbol 'USB_ETH' is not contained in the choice
>
> The description of commit 7a9618a22aad ("usb: gadget: allow to enable legacy
> drivers without USB_ETH") was a bit cryptic, as it did not change the
> behavior of USB_ETH other than allowing it to be built into the kernel
> alongside other legacy gadgets, which is not a valid configuration.
>
> As Felipe explained in the description for commit bc49d1d17dcf ("usb:
> gadget: don't couple configfs to legacy gadgets"), the configfs based
> gadgets can be freely configured as loadable modules or built-in
> drivers, but the legacy gadgets can only be modules if there is more
> than one of them, so we require the 'choice' statement here.
>
> This leaves the added USB_GADGET_LEGACY menuconfig symbol in place,
> but then restores the 'choice' below it, so we can enforce the
> single-legacy-gadget rule as before.

Hello Arnd,

A discussion is ongoing about whether or not commit 7a9618a22aad should be reverted.
Please drop this patch until a conclusion has been reached.

Thanks,

Bart.