Re: [PATCH] switchdev: add Kconfig dependencies for bridge

Arnd Bergmann
2021-08-02T20:44:25Z

On Mon, Aug 2, 2021 at 10:21 PM Vladimir Oltean <vladimir.oltean@nxp.com> wrote:
>
> On Mon, Aug 02, 2021 at 09:55:20PM +0200, Arnd Bergmann wrote:
> > On Mon, Aug 2, 2021 at 9:05 PM Vladimir Oltean <vladimir.oltean@nxp.com> wrote:
> > >
> > > On Mon, Aug 02, 2021 at 08:29:25PM +0200, Arnd Bergmann wrote:
> > > > If this looks correct to you, I can submit it as a standalone patch.
> > >
> > > I think it's easiest I just ask you to provide a .config that triggers
> > > actual build failures and we can go from there.
> >
> > This one is with an arm64 allmodconfig, plus
> >
> > CONFIG_PTP_1588_CLOCK=y
> > CONFIG_TI_K3_AM65_CPTS=y
> > CONFIG_TI_K3_AM65_CPSW_NUSS=y
>
> Yeah, ok, I remember now, I saw that TI_CPSW_SWITCHDEV is tristate, and
> incorrectly thought that TI_K3_AM65_CPSW_SWITCHDEV (which is mostly a
> copy-paste job of the main cpsw anyway, makes you cringe that they wrote
> a separate driver for it) is tristate too.

Right.

> The options are either to make TI_K3_AM65_CPSW_SWITCHDEV tristate like
> TI_CPSW_SWITCHDEV is, and to edit the Makefile accordingly to make
> am65-cpsw-switchdev.o part of obj-$(CONFIG_TI_K3_AM65_CPSW_SWITCHDEV),

This probably won't work as this is currently part of the ti-am65-cpsw-nuss.ko
module, so I would assume that it's not easy to separate from the main module.

> or to extend the BRIDGE || BRIDGE=n dependency to TI_K3_AM65_CPSW_NUSS
> which is the direct tristate dependency of CONFIG_TI_K3_AM65_CPSW_SWITCHDEV,

That would work, but it's slightly more heavy-handed than my proposal, as this
prevents TI_K3_AM65_CPSW_NUSS from being built-in when BRIDGE is a module,
even when switchdev support is completely disabled.

> and to make CONFIG_TI_K3_AM65_CPSW_SWITCHDEV simply depend on BRIDGE.

This would not be needed then I think.

Arnd