From: Anssi Hannula <anssi.hannula@iki.fi>
To: ajay khandelwal <ajay.lforum@gmail.com>
Cc: alsa-devel@alsa-project.org
Subject: Re: IEC61937/SPDIF
Date: Tue, 14 Jun 2011 21:09:43 +0300 [thread overview]
Message-ID: <4DF7A3E7.5080907@iki.fi> (raw)
In-Reply-To: <BANLkTik_MxbjfXDu13=ajRoaOUucHT+HWA@mail.gmail.com>
On 14.06.2011 15:47, ajay khandelwal wrote:
> Hi All,
Hi!
I've worked with IEC61937, but I'm no ALSA expert, so I hope others
correct me if I'm wrong.
> I have to develop driver for SPDIF output of my board connected to HDMI.
>
> I'm not sure for following (specially IEC61937)
> 1) How should driver know if it is compressed audio or plain pcm
You can look at the bit 1 (0x02) of AES0 IEC958 channel status.
The driver generally provides IEC958 controls:
http://www.alsa-project.org/~tiwai/writing-an-alsa-driver/ch10s03.html
That are then used via hooks in "foo.pcm.hdmi.0" (or "foo.pcm.iec958.0"
for non-hdmi) definition in /usr/share/alsa/cards/foo.conf (look at
existing drivers for examples).
Applications can then set these flags by e.g. opening the ALSA audio
device as "hdmi:AES0=0x06,AES1=0x82" etc.
> 2) Is their any plugin available for IEC61937, I could see only for IEC958
No.
> 3) Who should create burst preamble, some plug in or driver.
Currently they are created by the applications themselves.
--
Anssi Hannula
next prev parent reply other threads:[~2011-06-14 18:09 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-14 12:47 IEC61937/SPDIF ajay khandelwal
2011-06-14 18:09 ` Anssi Hannula [this message]
2011-06-14 18:17 ` IEC61937/SPDIF Takashi Iwai
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=4DF7A3E7.5080907@iki.fi \
--to=anssi.hannula@iki.fi \
--cc=ajay.lforum@gmail.com \
--cc=alsa-devel@alsa-project.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.