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

[Uwe Kleine-König]

Hello Johan,

On Wed, Dec 18, 2019 at 10:38:06AM +0100, Johan Hovold wrote:
> On Wed, Dec 18, 2019 at 10:29:58AM +0100, Uwe Kleine-König wrote:
> > 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.
> 
> No, and I don't have time to look into this right now.
> 
> It's more about the general principle that a patch should do one thing;

IMHO it does one thing: It does what 54edb425346a intended to do in the
right way.

But I don't feel strong here. If you prefer to revert, that's ok, too.
Not sure I will find the motivation then, to reimplement the
cleanup, though.

Best regards
Uwe

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Pengutronix e.K.                           | Uwe Kleine-König            |
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