Re: [PATCH] serdev: fix builds with CONFIG_SERIAL_DEV_BUS=m

[Uwe Kleine-König]

On Wed, Dec 18, 2019 at 10:06:06AM +0100, Johan Hovold wrote:
> On Wed, Dec 18, 2019 at 09:38:42AM +0100, Uwe Kleine-König wrote:
> > Commit 54edb425346a ("serdev: simplify Makefile") broke builds with
> > serdev configured as module. I don't understand it completely yet, but
> > it seems that
> > 
> > 	obj-$(CONFIG_SERIAL_DEV_BUS) += serdev/
> > 
> > in drivers/tty/Makefile with CONFIG_SERIAL_DEV_BUS=m doesn't result in
> > code that is added using obj-y in drivers/tty/serdev/Makefile being
> > compiled. So instead of dropping $(CONFIG_SERIAL_DEV_BUS) in serdev's
> > Makefile, drop it in drivers/tty/Makefile.
> 
> Why not simply revert the offending patch? There are some dependencies
> here related to how the tty layer is built. If you're still not certain
> on why things broke, I suggest just reverting for now.

I see that it is not easy to define what obj-y should do in a Makefile
that is included via obj-m. Now it is the other way round and that
should be safe. This construct is used in several places, so I'd say the
patch is fine unless you have more concrete concerns.

Best regards
Uwe

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