Re: [PATCH] ASoC: SOF: sort out Kconfig, again

From: Daniel Baluta <daniel.baluta@gmail.com>
To: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>,
	Arnd Bergmann <arnd@arndb.de>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>,
	ALSA Development Mailing List <alsa-devel@alsa-project.org>,
	Kai Vehmanen <kai.vehmanen@linux.intel.com>,
	Daniel Baluta <daniel.baluta@nxp.com>,
	Sascha Hauer <s.hauer@pengutronix.de>,
	Takashi Iwai <tiwai@suse.com>, YueHaibing <yuehaibing@huawei.com>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	NXP Linux Team <linux-imx@nxp.com>,
	Mark Brown <broonie@kernel.org>,
	Ranjani Sridharan <ranjani.sridharan@linux.intel.com>,
	Pengutronix Kernel Team <kernel@pengutronix.de>,
	Shawn Guo <shawnguo@kernel.org>,
	Fabio Estevam <festevam@gmail.com>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	sound-open-firmware@alsa-project.org
Subject: Re: [PATCH] ASoC: SOF: sort out Kconfig, again
Date: Wed, 29 Apr 2020 11:21:35 +0300	[thread overview]
Message-ID: <CAEnQRZCr0NAfx4UGcd3v6Cr5bZpUmQg5VCG9OA=aj=4uJX0qOg@mail.gmail.com> (raw)
In-Reply-To: <b784c008-7094-05cb-6200-6b246ff39bb8@linux.intel.com>

Hi Arnd, Pierre,

Thanks for looking at this.

> >>> Thanks Arnd, do you mind sharing your config?
> >>
> >> https://pastebin.com/HRX5xi3R
> >
> > will give it a try, thanks!
> >
> >>> We noticed last week that
> >>> there's a depend/select confusion might be simpler to fix, see
> >>> https://github.com/thesofproject/linux/pull/2047/commits
> >>>
> >>> If I look at the first line I see a IMX_DSP=n which looks exactly like
> >>> what we wanted to fix.
> >>
> >> Yes, I think that fix addresses the build warning as well, but looking
> >> more closely I don't think it's what you want: If you do this on
> >> a config that has the IMX_DSP disabled, it would appear to the
> >> user that you have enabled the drivers, but the actual code is still
> >> disabled.
> >
> > Are you sure? we added a select IMX_DSP, so not sure how it can be
> > disabled?
>
> I just tested Arnd's config with the patch we came up with for SOF
> (attached) and it makes the unmet dependency go away and builds fine.
> the problem is really using select IMX_DSP if it can be disabled by
> something else. My proposal looks simpler but I will agree it's not
> necessarily super elegant to move the dependency on IMX_BOX into SOF, so
> no sustained objection from me on Arnd's proposal.
>
> Daniel, this is your part of SOF, please chime in.

I would go in favor of Arnd's patch as it gets rid of exposing
IMX_MBOX into SOF.
The code will be fine even IMX_DSP=n, because the exported functions
used by SOF have dummy implementations in case IMX_DSP is not selected.

One concern is that we could end up in a case where IMX_DSP={y|m} but
IMX_MBOX=n.

Technically this is not possible because IMX_DSP depends on IMX_MBOX. So,
one cannot generate such a .config file from menuconfig interface.

You can add my:

Acked-by: Daniel Baluta <daniel.baluta@nxp.com>