From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sangbeom Kim <sbkim73@samsung.com>
Subject: WM8994 playback delay
Date: Thu, 29 Mar 2012 08:02:29 +0900
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To: 'Mark Brown' <broonie@opensource.wolfsonmicro.com>
Cc: alsa-devel@alsa-project.org, sbkim01@gmail.com, sangsu4u.park@samsung.com, 'Liam Girdwood' <lrg@ti.com>
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Hi, Mark,

Currently, We are developing SMDK with Exynos5250 and  WM8994 on 3.3-rc6.
We try to enable CONFIG_PM_RUNTIME and on/off control of power domain.
But It has playback delay in the first playback.(3~4sec and 6/10times)

In that time, Log maessage is 
'wm8994-codec wm8994-codec: Timed out waiting for DC Servo 300'
wait_for_dc_servo() function generate above message on sound/soc/codecs/wm_hubs.c

After removing wait_for_dc_servo for testing, playback delay is disappeared.
So, Could you please explain the  purporse of wait_for_dc_servo()?
If wait_for_dc_servo() is removed, What kind of problem can be happened?

Thanks,
Sangbeom.