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Date:   Tue, 02 Mar 2021 18:23:03 +0100
Message-ID: <s5hr1kxeah4.wl-tiwai@suse.de>
From:   Takashi Iwai <tiwai@suse.de>
To:     Mark Brown <broonie@kernel.org>
Cc:     Jon Hunter <jonathanh@nvidia.com>, linux-tegra@vger.kernel.org,
        alsa-devel@alsa-project.org, Liam Girdwood <lgirdwood@gmail.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ASoC: soc-core: Prevent warning if no DMI table is present
In-Reply-To: <20210302124913.GC4522@sirena.org.uk>
References: <20210302092712.310705-1-jonathanh@nvidia.com>
        <20210302124913.GC4522@sirena.org.uk>
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On Tue, 02 Mar 2021 13:49:13 +0100,
Mark Brown wrote:
> 
> On Tue, Mar 02, 2021 at 09:27:12AM +0000, Jon Hunter wrote:
> > Many systems do not provide a DMI table and on these systems a warning,
> > such as the following, is printed on boot ...
> > 
> >  WARNING KERN tegra-audio-graph-card sound: ASoC: no DMI vendor name!
> > 
> > If DMI support is enabled in the kernel, there is no simple way to
> > detect if a DMI table is table or not. Note that the variable
> > 'dmi_available' is not exported and so cannot be used by kernel modules.
> 
> We could fix that, or provide an accessor function?  Or only warn if
> we're on an ACPI system (which we can check from a module).  This really
> does feel like something we should be warning about on systems that are
> supposed to have DMI information available as standard.

I had the same feeling when I took a look at the patch, but later
changed mind, since the error will pop up also if a system has an
unmatured BIOS with some bogus vendor DMI string, too.  That is, users
of such a machine gets always an error message although this isn't any
serious problem unless you need a dedicated UCM profile (which can't
be used on such a system in anyway).

So, I agree that exporting dmi_avilable could improve the situation a
bit, but the error level needs still reconsideration.


Takashi