On 08/19/2013 06:18 AM, bardliao@realtek.com wrote:
From: Bard Liao bardliao@realtek.com
Add mute/unmute control in widget event and modify the power on/off sequence to avoid pop noise.
This version breaks both headphone and speaker output. I see the following issues:
1)
After a reboot, if all of "{HP,Speaker} [LR] Playback Switch" are on/unmuted, and I start playback, then something sets all those controls to off/muted. I suspect this is related to function rt5640_hp_event() twiddling the same RT5640_[LR]_MUTE bits that the hp_[lr]_enable_control controls twiddle.
2)
If playback is running, and (1) has caused all output to be muted, and I then run alsamixer and enable/unmute "HP L Playback Switch", I hear sound on both the L and R headphone channels for a very brief time, then output switches to the L channel only. Similar happens if I unmute "HP R Playback Switch" first. Unmuting both switches does produce stereo sound as expected.
I don't know if this also happens for the speaker output, since the board is too far away from me to easily tell which speakers are playing.