Re: [PATCH v2] kselftest: alsa: Add simplistic test for ALSA mixer controls kselftest

From: Jaroslav Kysela <perex@perex.cz>
To: Mark Brown <broonie@kernel.org>, Takashi Iwai <tiwai@suse.de>,
	Shuah Khan <shuah@kernel.org>,
	alsa-devel@alsa-project.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v2] kselftest: alsa: Add simplistic test for ALSA mixer controls kselftest
Date: Tue, 7 Dec 2021 09:05:43 +0100	[thread overview]
Message-ID: <77e39efd-e49d-cea1-1822-0e2262a766c9@perex.cz> (raw)
In-Reply-To: <Ya7TAHdMe9i41bsC@workstation>

On 07. 12. 21 4:20, Takashi Sakamoto wrote:
> As another topic, the runtime of alsa-lib application largely differs
> between process user due to the result of parsing text files for
> configuration space. I can easily imagine that developers unfamiliar to
> alsa-lib carelessly adds invalid or inadequate configurations to files
> under target path of alsa-lib configuration space, and they are puzzled
> since they are unaware of the fact that the kselftest is affected by
> userspace stuffs for the runtime.
The alsa-lib configuration can be restricted. I would suggest to use 
snd_ctl_open_lconf() function with a simple configuration which defines only 
ctl.hw device. In this case, the global configuration is not used, so the user 
errors are eliminated. Another way is to use the environment variable for the 
global alsa-lib configuration - ALSA_CONFIG_DIR.

I will try prepare a patch for snd_ctl_open_lconf().

					Jaroslav

BTW: Thank you Mark for this test.

-- 
Jaroslav Kysela <perex@perex.cz>
Linux Sound Maintainer; ALSA Project; Red Hat, Inc.