[alsa-devel] WM8994 playback delay

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.