[alsa-devel] [PATCH] [RFC 8/13] Intel SST sound card driver

[Harsha, Priya]

>-----Original Message-----
>From: Mark Brown [mailto:broonie at opensource.wolfsonmicro.com]
>Sent: Tuesday, July 07, 2009 5:12 PM
>To: Harsha, Priya
>Cc: Koul, Vinod; alsa-devel at alsa-project.org
>Subject: Re: [alsa-devel] [PATCH] [RFC 8/13] Intel SST sound card driver
>
>On Tue, Jul 07, 2009 at 12:05:45PM +0530, Harsha, Priya wrote:
>> >-----Original Message-----
>> >From: Mark Brown [mailto:broonie at opensource.wolfsonmicro.com]
>
>> >ALSA core has an interface for representing jacks to user space which
>> >should be used here - see include/sound/jack.h.
>
>> Thanks for the note. I shall look into it further. Can you suggest any
>> example ALSA driver that uses this functionality so that I can have a
>
>A lot of the HDA drivers use it and there's a wrapper for ASoC too -
>it's fairly likely that if you're running a current kernel your desktop
>PC will support this interface already.  Searching the kernel source for
>snd_jack_new() should turn up everything there is at the minute.
>
>> reference. Also quick question around this, can I use this jack.h to
>> event the user space?
>
>Yes, the jacks currently appear as input devices to applications.
>Takashi was also considering adding some ALSA-specific ways of reading
>the state to go alongside these.
If I create a jack sense device, how would an application use it? Currently do we have any mechanism in ALSA to send events to user space when a jack is detected? If not, would it be ok if I stick to netlink events for now. We have a platform specific daemon that is being developed that listens on netlink events and that is why the driver sends them. 

Thanks,
Harsha