[alsa-devel] [PATCH v3] sound/soc/lapis: add platform driver for ML7213

Tomoya MORINAGA tomoya.rohm at gmail.com
Thu Mar 8 03:06:47 CET 2012

On Wed, Mar 7, 2012 at 8:46 PM, Mark Brown
<broonie at opensource.wolfsonmicro.com> wrote:
>> >> if these platform devices aren't used, device detection doesn't work correctly.
>> >> So, I added these.
>> > You've not actually mentioned the problem you were seeing...
>> I saw mapping problem between machine driver and platform driver.
>> e.g.  cpu_dai_name "ml7213ioh"
> You've still not explained the problem you're seeing but this sounds
> like something that should work.  Please address the

* Faced problem if there are no platform settings.
machine driver's hw_params is not called
platform_driver's functions(snd_pcm_ops, snd_soc_platform_driver) are
not called.

As a result, the following message is not showed . (by soc_pcm.c)
printk(KERN_INFO "asoc: %s <-> %s mapping ok\n", codec_dai->name,

>> > Apart from anything else you've got the interrupt requested as
>> > IRQF_SHARED so the interrupt could get called at any time.  It's also
>> > not clear that you've got the hardware in a known good state.
>> Do you mean request_irq should move to somewhere, like open() or
>> hw_params() or ... ?
> You need to do enough hardware and software initialisation prior to
> requesting the interrupt to ensure that if an interrupt does happen it
> won't cause any ill effects.  Checks in the interrupt handler to make
> sure things like the ALSA layer stuff have been set up can also be used
> to make the interrupt handler safer.

I can understand your concern.
Let me clarify your think.
You think that interrupt handler must check whether ALSA initialization has
already finished or not before interrupt process executes.

ROHM Co., Ltd.

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