* Emulated IEC958 Card
@ 2010-09-15 14:05 Jassi Brar
2010-09-17 12:20 ` Jassi Brar
0 siblings, 1 reply; 6+ messages in thread
From: Jassi Brar @ 2010-09-15 14:05 UTC (permalink / raw)
To: alsa-devel; +Cc: Takashi Iwai, yadi brar, Liam Girdwood, Mark Brown
Hi,
Ok, so there is already the iec958 plugin, but wouldn't it be nice to have an
'Emulated IEC958-Card' driver that implements implements all the possible
components of the IEC958-cum-AES/EBU specification. The user could have
the look and feel of a real card via ALSA control and audio i/f ....
User Data can be
provided too (which lacks in the iec958 plugin ?)
This driver might be boon for low-end embedded devices which have neither IEC958
controller in the SoC nor a codec chip that supports it. In fact the
SPDIF controller
of one SoC that I know implements only a subset of the standard with
limitations.
The only requirement for the emulated-iec958 card would be a shifter
with deep enough
fifo, that can shift out bits at around 6Mbps (for 48KHz Stereo). And
most SoCs have
such a resource available that can be put to the use -- OMAP has
McBSP, Samsung's
and other SoCs can leverage a SPI controller.
Any suggestions welcome.
Regards,
Jassi
PS: I start the topic upon insistence from Angat
<yadi.brar01@gmail.com>, a grad student who
wanted to implement the feature for his univ project on his beagle board.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Emulated IEC958 Card
2010-09-15 14:05 Emulated IEC958 Card Jassi Brar
@ 2010-09-17 12:20 ` Jassi Brar
2010-09-17 12:27 ` Mark Brown
0 siblings, 1 reply; 6+ messages in thread
From: Jassi Brar @ 2010-09-17 12:20 UTC (permalink / raw)
To: alsa-devel; +Cc: Takashi Iwai, yadi brar, Liam Girdwood, Mark Brown
On Wed, Sep 15, 2010 at 11:05 PM, Jassi Brar <jassisinghbrar@gmail.com> wrote:
> Hi,
>
> Ok, so there is already the iec958 plugin, but wouldn't it be nice to have an
> 'Emulated IEC958-Card' driver that implements implements all the possible
> components of the IEC958-cum-AES/EBU specification. The user could have
> the look and feel of a real card via ALSA control and audio i/f ....
> User Data can be
> provided too (which lacks in the iec958 plugin ?)
>
> This driver might be boon for low-end embedded devices which have neither IEC958
> controller in the SoC nor a codec chip that supports it. In fact the
> SPDIF controller
> of one SoC that I know implements only a subset of the standard with
> limitations.
>
> The only requirement for the emulated-iec958 card would be a shifter
> with deep enough
> fifo, that can shift out bits at around 6Mbps (for 48KHz Stereo). And
> most SoCs have
> such a resource available that can be put to the use -- OMAP has
> McBSP, Samsung's
> and other SoCs can leverage a SPI controller.
>
> Any suggestions welcome.
ASoC folks, Mark, Liam,
I would really appreciate your take on the idea if you could spare a
few moments please.
Actually I just might get our AP design folks to implement such a
dedicated shifter IP in later SoC.
Also, I don't wanna direct the bloke(Angat) in a direction that is
outright unacceptable
to maintainers -- if it is so.
Thanks
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Alsa-devel mailing list
Alsa-devel@alsa-project.org
http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Emulated IEC958 Card
2010-09-17 12:20 ` Jassi Brar
@ 2010-09-17 12:27 ` Mark Brown
2010-09-17 12:42 ` Jassi Brar
0 siblings, 1 reply; 6+ messages in thread
From: Mark Brown @ 2010-09-17 12:27 UTC (permalink / raw)
To: Jassi Brar; +Cc: Takashi Iwai, yadi brar, alsa-devel, Liam Girdwood
On Fri, Sep 17, 2010 at 09:20:16PM +0900, Jassi Brar wrote:
> I would really appreciate your take on the idea if you could spare a
> few moments please.
> Actually I just might get our AP design folks to implement such a
> dedicated shifter IP in later SoC.
> Also, I don't wanna direct the bloke(Angat) in a direction that is
> outright unacceptable
> to maintainers -- if it is so.
The idea of having a full IEC958 emulation layer that just needs a
generic serial port or shifter accessed through some standard interface
seems entirely sensible. This isn't so different to what things like
the McBSP, PXA SSP or FSL SSI ports do.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Emulated IEC958 Card
2010-09-17 12:27 ` Mark Brown
@ 2010-09-17 12:42 ` Jassi Brar
2010-09-17 12:47 ` Mark Brown
0 siblings, 1 reply; 6+ messages in thread
From: Jassi Brar @ 2010-09-17 12:42 UTC (permalink / raw)
To: Mark Brown; +Cc: Takashi Iwai, yadi brar, alsa-devel, Liam Girdwood
On Fri, Sep 17, 2010 at 9:27 PM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
> On Fri, Sep 17, 2010 at 09:20:16PM +0900, Jassi Brar wrote:
>
>> I would really appreciate your take on the idea if you could spare a
>> few moments please.
>> Actually I just might get our AP design folks to implement such a
>> dedicated shifter IP in later SoC.
>> Also, I don't wanna direct the bloke(Angat) in a direction that is
>> outright unacceptable
>> to maintainers -- if it is so.
>
> The idea of having a full IEC958 emulation layer that just needs a
> generic serial port or shifter accessed through some standard interface
> seems entirely sensible. This isn't so different to what things like
> the McBSP, PXA SSP or FSL SSI ports do.
Yup, I knew those features but am unaware of any situation where they drive out
IEC958 - they just run I2S, SPI, TDM (?)
Also, IMO, it would make more sense to implement it as a Virtual card
independent
of ASoC(outside of linux/sound/soc/), with number of devices equalling
the number
of shifters registered.
Thank you.
_______________________________________________
Alsa-devel mailing list
Alsa-devel@alsa-project.org
http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Emulated IEC958 Card
2010-09-17 12:42 ` Jassi Brar
@ 2010-09-17 12:47 ` Mark Brown
2010-09-17 13:01 ` Jassi Brar
0 siblings, 1 reply; 6+ messages in thread
From: Mark Brown @ 2010-09-17 12:47 UTC (permalink / raw)
To: Jassi Brar; +Cc: Takashi Iwai, yadi brar, alsa-devel, Liam Girdwood
On Fri, Sep 17, 2010 at 09:42:46PM +0900, Jassi Brar wrote:
> On Fri, Sep 17, 2010 at 9:27 PM, Mark Brown
> > The idea of having a full IEC958 emulation layer that just needs a
> > generic serial port or shifter accessed through some standard interface
> > seems entirely sensible. This isn't so different to what things like
> > the McBSP, PXA SSP or FSL SSI ports do.
> Yup, I knew those features but am unaware of any situation where they drive out
> IEC958 - they just run I2S, SPI, TDM (?)
Me either, I just meant that this is a well known model for structuring
this sort of hardware and software so it should be a good model to
follow.
> Also, IMO, it would make more sense to implement it as a Virtual card
> independent
> of ASoC(outside of linux/sound/soc/), with number of devices equalling
> the number
> of shifters registered.
I agree, though it would be nice to have some facility for implementing
an interface between the two since you can get IEC958 I/O on ASoC
CODECs. I don't think that's needed at first pass, but it may come up
at some point.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Emulated IEC958 Card
2010-09-17 12:47 ` Mark Brown
@ 2010-09-17 13:01 ` Jassi Brar
0 siblings, 0 replies; 6+ messages in thread
From: Jassi Brar @ 2010-09-17 13:01 UTC (permalink / raw)
To: Mark Brown; +Cc: Takashi Iwai, yadi brar, alsa-devel, Liam Girdwood
On Fri, Sep 17, 2010 at 9:47 PM, Mark Brown
<broonie@opensource.wolfsonmicro.com> wrote:
>> Also, IMO, it would make more sense to implement it as a Virtual card
>> independent
>> of ASoC(outside of linux/sound/soc/), with number of devices equalling
>> the number
>> of shifters registered.
>
> I agree, though it would be nice to have some facility for implementing
> an interface between the two since you can get IEC958 I/O on ASoC
> CODECs. I don't think that's needed at first pass, but it may come up
> at some point.
Ok, we'll try to figure that out.
Thanks.
_______________________________________________
Alsa-devel mailing list
Alsa-devel@alsa-project.org
http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2010-09-17 13:01 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2010-09-15 14:05 Emulated IEC958 Card Jassi Brar
2010-09-17 12:20 ` Jassi Brar
2010-09-17 12:27 ` Mark Brown
2010-09-17 12:42 ` Jassi Brar
2010-09-17 12:47 ` Mark Brown
2010-09-17 13:01 ` Jassi Brar
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