From: Takashi Iwai <tiwai@suse.de>
To: Jon Hunter <jonathanh@nvidia.com>
Cc: Liam Girdwood <lgirdwood@gmail.com>,
Mark Brown <broonie@kernel.org>, Jaroslav Kysela <perex@perex.cz>,
Takashi Iwai <tiwai@suse.com>,
"Thierry Reding" <thierry.reding@gmail.com>,
Sameer Pujar <spujar@nvidia.com>, <alsa-devel@alsa-project.org>,
<linux-tegra@vger.kernel.org>,
"Oswald Buddenhagen" <oswald.buddenhagen@gmx.de>
Subject: Re: [PATCH] ASoC: tegra: Fix Master Volume Control
Date: Tue, 13 Jun 2023 11:57:24 +0200 [thread overview]
Message-ID: <87legnelbv.wl-tiwai@suse.de> (raw)
In-Reply-To: <87mt13elff.wl-tiwai@suse.de>
On Tue, 13 Jun 2023 11:55:16 +0200,
Takashi Iwai wrote:
>
> On Tue, 13 Jun 2023 11:34:53 +0200,
> Jon Hunter wrote:
> >
> > Commit 3ed2b549b39f ("ALSA: pcm: fix wait_time calculations") corrected
> > the PCM wait_time calculations and in doing so reduced the calculated
> > wait_time. This exposed an issue with the Tegra Master Volume Control
> > (MVC) device where the reduced wait_time caused the MVC to fail. For now
> > fix this by setting the default wait_time for Tegra to be 500ms.
> >
> > Fixes: 3ed2b549b39f ("ALSA: pcm: fix wait_time calculations")
> > Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
>
> Hm, it's still not clear why it fails. The commit above changes the
> timeout of wait_for_avail() to the full-buffer + 10% margin. In
> thoery, the loop should abort after the full buffer read, and that
> must be enough. If there were a large FIFO behind, it might be
> overflow, but the fifo_size of Tegra driver seems 4, so it's
> negligible.
>
> If extending the timeout "fixes" the problem, it might indicate that
> the period update IRQ is triggered too late. Could you measure the
> timing of each snd_pcm_period_elapsed() and wait_for_avail() call?
OTOH, it's already at a pretty late stage for 6.4, and we need an
urgent regression fix. So it's better to paper over it now, while
hunting further for the real culprit.
Takashi
next prev parent reply other threads:[~2023-06-13 9:58 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-06-13 9:34 [PATCH] ASoC: tegra: Fix Master Volume Control Jon Hunter
2023-06-13 9:55 ` Takashi Iwai
2023-06-13 9:57 ` Takashi Iwai [this message]
2023-06-13 10:25 ` Jon Hunter
2023-06-13 13:23 ` Linux regression tracking #adding (Thorsten Leemhuis)
2023-06-13 16:29 ` Mark Brown
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=87legnelbv.wl-tiwai@suse.de \
--to=tiwai@suse.de \
--cc=alsa-devel@alsa-project.org \
--cc=broonie@kernel.org \
--cc=jonathanh@nvidia.com \
--cc=lgirdwood@gmail.com \
--cc=linux-tegra@vger.kernel.org \
--cc=oswald.buddenhagen@gmx.de \
--cc=perex@perex.cz \
--cc=spujar@nvidia.com \
--cc=thierry.reding@gmail.com \
--cc=tiwai@suse.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).