[PATCH v2 1/2] kselftest: alsa: Check for event generation when we write to controls

[Jaroslav Kysela]

On 02. 02. 22 15:10, 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 at kernel.org>
> Reviewed-by: Shuah Khan <skhan at linuxfoundation.org>

...

> +		/* The ID returned from the event is 1 less than numid */
> +		mask = snd_ctl_event_elem_get_mask(event);
> +		ev_id = snd_ctl_event_elem_get_numid(event);
> +		if (ev_id != snd_ctl_elem_info_get_numid(ctl->info)) {
> +			ksft_print_msg("Event for unexpected ctl %s\n",
> +				       snd_ctl_event_elem_get_name(event));
> +			continue;
> +		}
> +	} while ((mask & SND_CTL_EVENT_MASK_VALUE) != SND_CTL_EVENT_MASK_VALUE);

A special check for SND_CTL_EVENT_MASK_REMOVE (~0U) is missing here.

For the rest:

Reviewed-by: Jaroslav Kysela <perex at perex.cz>

					Thanks,
						Jaroslav

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