From: "Alexander E. Patrakov" <patrakov@gmail.com>
To: David Henningsson <david.henningsson@canonical.com>,
"Deucher, Alexander" <Alexander.Deucher@amd.com>,
Takashi Iwai <tiwai@suse.de>
Cc: Anssi Hannula <anssi.hannula@iki.fi>,
"alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>
Subject: Re: Radeon unconnected HDMI eats samples at 280 kHz
Date: Sat, 20 Sep 2014 15:31:01 +0600 [thread overview]
Message-ID: <541D4955.6040708@gmail.com> (raw)
In-Reply-To: <541CC506.601@canonical.com>
20.09.2014 06:06, David Henningsson wrote:
> From the audio driver's point of view, if you have 1 audio pin, then
> that's one display. Presence detect, as well as ELD information, should
> reflect the status of that one display.
>
> How to multiplex that against several audio capable monitors is tricky,
> but it's something you have to solve on the video driver side.
> I'm not sure how other video drivers have solved that, or if AMD/ATI is
> the only manufacturer who has cards with this hw design (i e fewer audio
> pins than audio capable outputs).
A similar problem exists for Intel on Haswell, and here is how they
solved it.
They have three HDMI outputs, but only two audio pins. Audio can be
routed to any two of the three connected monitors. This is done by
opening the following PCMs: hdmi:0,0, hdmi:0,1 and hdmi:0,2, with 1:1
correspondence to the physical outputs. I.e. the driver pretends that
there are three subdevices. However, only two of them (any two) can be
opened simultaneously. The third one gives -EBUSY on attempts to open it.
--
Alexander E. Patrakov
next prev parent reply other threads:[~2014-09-20 9:31 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-09-17 13:40 Radeon unconnected HDMI eats samples at 280 kHz David Henningsson
2014-09-17 21:26 ` Anssi Hannula
2014-09-18 4:13 ` David Henningsson
2014-09-18 7:33 ` Takashi Iwai
2014-09-18 7:54 ` David Henningsson
2014-09-18 22:29 ` Deucher, Alexander
2014-09-19 13:38 ` David Henningsson
2014-09-19 14:14 ` Deucher, Alexander
2014-09-19 17:47 ` David Henningsson
2014-09-19 18:19 ` Alexander E. Patrakov
2014-09-19 23:35 ` David Henningsson
2014-09-20 9:37 ` Anssi Hannula
2014-09-20 9:39 ` Alexander E. Patrakov
2014-09-19 23:32 ` Deucher, Alexander
2014-09-20 0:06 ` David Henningsson
2014-09-20 9:31 ` Alexander E. Patrakov [this message]
2014-09-22 12:46 ` Deucher, Alexander
2014-09-22 14:39 ` David Henningsson
2014-09-22 14:52 ` Deucher, Alexander
2014-09-23 9:47 ` David Henningsson
2014-09-23 14:07 ` Deucher, Alexander
2014-09-24 9:27 ` David Henningsson
2014-09-24 21:37 ` Deucher, Alexander
2014-09-30 12:24 ` David Henningsson
2014-09-30 12:45 ` Deucher, Alexander
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=541D4955.6040708@gmail.com \
--to=patrakov@gmail.com \
--cc=Alexander.Deucher@amd.com \
--cc=alsa-devel@alsa-project.org \
--cc=anssi.hannula@iki.fi \
--cc=david.henningsson@canonical.com \
--cc=tiwai@suse.de \
/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.