From: Mark Brown <broonie@kernel.org>
To: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Jean-Francois Moine <moinejf@free.fr>,
alsa-devel@alsa-project.org, Lars-Peter Clausen <lars@metafoo.de>,
Philipp Zabel <p.zabel@pengutronix.de>,
David Airlie <airlied@linux.ie>,
Arnaud Pouliquen <arnaud.pouliquen@st.com>,
Liam Girdwood <lgirdwood@gmail.com>, Jyri Sarha <jsarha@ti.com>,
Takashi Iwai <tiwai@suse.de>,
Benjamin Gaignard <benjamin.gaignard@linaro.org>
Subject: Re: [RFC 1/6] video: hdmi: add helper function for N and CTS
Date: Tue, 19 Jan 2016 17:14:12 +0000 [thread overview]
Message-ID: <20160119171412.GP6588@sirena.org.uk> (raw)
In-Reply-To: <20160119165430.GN19062@n2100.arm.linux.org.uk>
[-- Attachment #1.1: Type: text/plain, Size: 1195 bytes --]
On Tue, Jan 19, 2016 at 04:54:30PM +0000, Russell King - ARM Linux wrote:
> On Tue, Jan 19, 2016 at 02:40:31PM +0100, Arnaud Pouliquen wrote:
> > From: Moise Gergaud <moise.gergaud@st.com>
> > Add helper function to compute HDMI CTS and N parameters
> > Implementation is based on HDMI 1.4b specification.
> You should note that these CTS/N parameters are for where the audio and
> video clocks are coherent: iow, they are derived from the same source.
> If they can drift (because they're generated from different sources)
> then a hardware implementation which automatically calculates CTS is
> needed.
> However, some of the values given in the HDMI specs for CTS are actually
> two values, because a single value does not specify the audio clock even
> with the N values given. For these, the values returned will not give
> an accurate clock - this should also be noted.
> Next, does "pixel clock" make sense when you have pixel repetition?
> Would calling this "tdms_clock" be more accurate to the specification
> and less mis-leading to users?
It'd also be good to capture some of the above information from Russell
in the code so other people don't miss it when using the helpers.
[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 473 bytes --]
[-- Attachment #2: Type: text/plain, Size: 0 bytes --]
next prev parent reply other threads:[~2016-01-19 17:14 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-19 13:40 [RFC 0/6] sti: add audio interface to the hdmi driver Arnaud Pouliquen
2016-01-19 13:40 ` [RFC 1/6] video: hdmi: add helper function for N and CTS Arnaud Pouliquen
2016-01-19 16:54 ` Russell King - ARM Linux
2016-01-19 17:14 ` Mark Brown [this message]
2016-01-20 13:26 ` Arnaud Pouliquen
2016-01-20 13:39 ` Russell King - ARM Linux
2016-01-19 13:40 ` [RFC 2/6] ALSA: pcm: add IEC958 channel status control helper Arnaud Pouliquen
2016-01-19 17:00 ` Russell King - ARM Linux
2016-01-20 14:16 ` Arnaud Pouliquen
2016-01-19 13:40 ` [RFC 3/6] ASoC: core: add code to complete dai init after pcm creation Arnaud Pouliquen
2016-01-19 13:40 ` [RFC 4/6] drm: sti: Add ASoC generic hdmi codec support Arnaud Pouliquen
2016-01-19 17:06 ` Russell King - ARM Linux
2016-01-19 13:40 ` [RFC 5/6] ASoc: hdmi-codec: add IEC control Arnaud Pouliquen
2016-01-19 13:40 ` [RFC 6/6] ARM: DT: b2120: add audio HDMI dai link in audio card Arnaud Pouliquen
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=20160119171412.GP6588@sirena.org.uk \
--to=broonie@kernel.org \
--cc=airlied@linux.ie \
--cc=alsa-devel@alsa-project.org \
--cc=arnaud.pouliquen@st.com \
--cc=benjamin.gaignard@linaro.org \
--cc=jsarha@ti.com \
--cc=lars@metafoo.de \
--cc=lgirdwood@gmail.com \
--cc=linux@arm.linux.org.uk \
--cc=moinejf@free.fr \
--cc=p.zabel@pengutronix.de \
--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.