Re: [PATCH v3 1/2] kselftest: alsa: Check for event generation when we write to controls

From: Takashi Iwai <tiwai@suse.de>
To: Mark Brown <broonie@kernel.org>
Cc: Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.com>,
	Shuah Khan <shuah@kernel.org>,
	alsa-devel@alsa-project.org, linux-kselftest@vger.kernel.org,
	Takashi Sakamoto <o-takashi@sakamocchi.jp>,
	Shuah Khan <skhan@linuxfoundation.org>
Subject: Re: [PATCH v3 1/2] kselftest: alsa: Check for event generation when we write to controls
Date: Fri, 04 Feb 2022 10:40:08 +0100	[thread overview]
Message-ID: <s5h7dabx953.wl-tiwai@suse.de> (raw)
In-Reply-To: <20220202150902.19563-1-broonie@kernel.org>

On Wed, 02 Feb 2022 16:09:01 +0100,
Mark Brown wrote:
> 
> Add some coverage of event generation to mixer-test. Rather than doing a
> separate set of writes designed to trigger events we add a step to the
> existing write_and_verify() which checks to see if the value we read back
> from non-volatile controls matches the value before writing and that an
> event is or isn't generated as appropriate. The "tests" for events then
> simply check that no spurious or missing events were detected. This avoids
> needing further logic to generate appropriate values for each control type
> and maximises coverage.
> 
> When checking for events we use a timeout of 0. This relies on the kernel
> generating any event prior to returning to userspace when setting a control.
> That is currently the case and it is difficult to see it changing, if it
> does the test will need to be updated. Using a delay of 0 means that we
> don't slow things down unduly when checking for no event or when events
> fail to be generated.
> 
> We don't check behaviour for volatile controls since we can't tell what
> the behaviour is supposed to be for any given control.
> 
> Signed-off-by: Mark Brown <broonie@kernel.org>
> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
> Reviewed-by: Jaroslav Kysela <perex@perex.cz>

Thanks, applied now to for-next branch.

Takashi