All of lore.kernel.org
 help / color / mirror / Atom feed
From: Grant Likely <grant.likely@secretlab.ca>
To: linuxppc-dev@lists.ozlabs.org, alsa-devel@alsa-project.org,
	broonie@opensource.wolfsonmicro.com
Cc: lrg@slimlogic.co.uk
Subject: [PATCH 6/6] ASoC/mpc5200: Add fudge factor to value reported by	.pointer()
Date: Sat, 07 Nov 2009 01:34:55 -0700	[thread overview]
Message-ID: <20091107083448.18908.80366.stgit@angua> (raw)
In-Reply-To: <20091107081631.18908.82921.stgit@angua>

ALSA playback seems to be more reliable if the .pointer() hook reports
a value slightly into the period, rather than right on the period
boundary.  This patch adds a fudge factor of 1/4 the period size
to better estimate the actual position of the DMA engine in the
audio buffer.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
---

 sound/soc/fsl/mpc5200_dma.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/sound/soc/fsl/mpc5200_dma.c b/sound/soc/fsl/mpc5200_dma.c
index 9c88e15..ee5a606 100644
--- a/sound/soc/fsl/mpc5200_dma.c
+++ b/sound/soc/fsl/mpc5200_dma.c
@@ -297,7 +297,7 @@ psc_dma_pointer(struct snd_pcm_substream *substream)
 	else
 		s = &psc_dma->playback;
 
-	count = s->period_current * s->period_bytes;
+	count = (s->period_current * s->period_bytes) + (s->period_bytes >> 2);
 
 	return bytes_to_frames(substream->runtime, count);
 }

WARNING: multiple messages have this Message-ID (diff)
From: Grant Likely <grant.likely@secretlab.ca>
To: linuxppc-dev@lists.ozlabs.org, alsa-devel@alsa-project.org,
	broonie@opensource.wolfsonmicro.com
Cc: lrg@slimlogic.co.uk
Subject: [PATCH 6/6] ASoC/mpc5200: Add fudge factor to value reported by .pointer()
Date: Sat, 07 Nov 2009 01:34:55 -0700	[thread overview]
Message-ID: <20091107083448.18908.80366.stgit@angua> (raw)
In-Reply-To: <20091107081631.18908.82921.stgit@angua>

ALSA playback seems to be more reliable if the .pointer() hook reports
a value slightly into the period, rather than right on the period
boundary.  This patch adds a fudge factor of 1/4 the period size
to better estimate the actual position of the DMA engine in the
audio buffer.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
---

 sound/soc/fsl/mpc5200_dma.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/sound/soc/fsl/mpc5200_dma.c b/sound/soc/fsl/mpc5200_dma.c
index 9c88e15..ee5a606 100644
--- a/sound/soc/fsl/mpc5200_dma.c
+++ b/sound/soc/fsl/mpc5200_dma.c
@@ -297,7 +297,7 @@ psc_dma_pointer(struct snd_pcm_substream *substream)
 	else
 		s = &psc_dma->playback;
 
-	count = s->period_current * s->period_bytes;
+	count = (s->period_current * s->period_bytes) + (s->period_bytes >> 2);
 
 	return bytes_to_frames(substream->runtime, count);
 }

  parent reply	other threads:[~2009-11-07  8:34 UTC|newest]

Thread overview: 55+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-11-07  8:33 [PATCH 0/6] Fixups to MPC5200 ASoC drivers Grant Likely
2009-11-07  8:33 ` [PATCH 1/6] ASoC/mpc5200: Track DMA position by period number instead of bytes Grant Likely
2009-11-07  8:33   ` Grant Likely
2009-11-07 10:35   ` Liam Girdwood
2009-11-07 10:35     ` [alsa-devel] " Liam Girdwood
2009-11-07 16:50     ` Grant Likely
2009-11-07 16:50       ` [alsa-devel] " Grant Likely
2009-11-07  8:34 ` [PATCH 2/6] ASoC/mpc5200: get rid of the appl_ptr tracking nonsense Grant Likely
2009-11-07 12:51   ` Jon Smirl
2009-11-07 12:51     ` Jon Smirl
2009-11-07 13:04     ` Jon Smirl
2009-11-07 13:04       ` Jon Smirl
2009-11-07 18:53       ` Grant Likely
2009-11-07 18:53         ` Grant Likely
2009-11-07 18:51     ` Grant Likely
2009-11-07 18:51       ` Grant Likely
2009-11-07 20:12       ` Mark Brown
2009-11-07 20:12         ` [alsa-devel] " Mark Brown
2009-11-11 16:38         ` Jon Smirl
2009-11-11 16:38           ` Jon Smirl
2009-11-11 18:37           ` Mark Brown
2009-11-11 18:37             ` [alsa-devel] " Mark Brown
2009-11-11 19:24             ` Grant Likely
2009-11-11 19:24               ` [alsa-devel] " Grant Likely
2009-11-11 20:03               ` Mark Brown
2009-11-11 20:03                 ` [alsa-devel] " Mark Brown
2009-11-11 21:34               ` Jon Smirl
2009-11-11 21:34                 ` [alsa-devel] " Jon Smirl
2009-11-11 21:57                 ` Grant Likely
2009-11-11 21:57                   ` Grant Likely
2009-11-11 23:13                   ` Jon Smirl
2009-11-11 23:13                     ` [alsa-devel] " Jon Smirl
2009-11-12 12:10                     ` Mark Brown
2009-11-12 12:10                       ` [alsa-devel] " Mark Brown
2009-11-11 21:26             ` Jon Smirl
2009-11-11 21:26               ` [alsa-devel] " Jon Smirl
2009-11-07  8:34 ` [PATCH 3/6] ASoC/mpc5200: Improve printk debug output for trigger Grant Likely
2009-11-07  8:34 ` [PATCH 4/6] ASoC/mpc5200: add to_psc_dma_stream() helper Grant Likely
2009-11-07 12:33   ` Mark Brown
2009-11-07 12:33     ` [alsa-devel] " Mark Brown
2009-11-07  8:34 ` [PATCH 5/6] ASoC/mpc5200: fix enable/disable of AC97 slots Grant Likely
2009-11-07  8:34 ` Grant Likely [this message]
2009-11-07  8:34   ` [PATCH 6/6] ASoC/mpc5200: Add fudge factor to value reported by .pointer() Grant Likely
2009-11-07 18:11   ` Mark Brown
2009-11-07 18:11     ` [alsa-devel] " Mark Brown
2009-11-07 18:19     ` Grant Likely
2009-11-07 18:19       ` [alsa-devel] " Grant Likely
2009-11-07 19:33       ` Mark Brown
2009-11-07 19:33         ` [alsa-devel] " Mark Brown
2009-11-07 19:46         ` Grant Likely
2009-11-07 19:46           ` [alsa-devel] " Grant Likely
2009-11-07 12:57 ` [PATCH 0/6] Fixups to MPC5200 ASoC drivers Mark Brown
2009-11-07 12:57   ` [alsa-devel] " Mark Brown
2009-11-07 16:52   ` Grant Likely
2009-11-07 16:52     ` [alsa-devel] " Grant Likely

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=20091107083448.18908.80366.stgit@angua \
    --to=grant.likely@secretlab.ca \
    --cc=alsa-devel@alsa-project.org \
    --cc=broonie@opensource.wolfsonmicro.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=lrg@slimlogic.co.uk \
    /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.