@David Henningsson

If it's not necessary to join the upstream discussion I'd like to stay
over here if you don't mind.

After putting down that initial click noise I discovered a new one and
that's why the solution avoids two sorts of click noise. Both had been
appearing within the transition to D0. The first one (the initial click
noise) was caused by the eapd workaround - not powering down the speaker
0x10 widget within the transition to D3. The second one is quite soft
and that's why I didn't noticed it before. It was caused by the small
transition time to power up the AFG. It had been appearing at the same
time as the initial click noise as well as after the reboot  (when on
battery power). I read the hda specification and successfully tried to
use 75ms delay according to hda specification - "It is permissible for
the audio fidelity for analog outputs to be slightly degraded if audio
rendering begins immediately once the fully operational state is
entered. However, audio fidelity must not be degraded 75ms after the
transitioning to D0 state." Now there is no click noise with one
exception - when I try to record from D3 state there is a recorded
click. I tried to avoid that recorded click but the solution is in
extending the time to power up the AFG up to 300ms instead of 75ms. But
I think it's too long because the start of sound output is lagging. What
do you think about it?

Commentary:
the source is from dkms-hda_0.201212172004~quantal1
---------------------------
patch_conexant.c
---------------------------
+ * Copyright (c) 2006 Pototskiy Alex <alex.potots...@gmail.com>
just a typo

+ snd_hda_codec_set_power_to_all(codec, fg, power_state, false);
when transitioning to D3 set eapd_workaround to false because we need to power 
down the widget - Speaker 0x10, if it's not set it causes the initial click 
noise

+ msleep(75);
time to power up the AFG to avoid the soft click noise

+ .set_power_state = conexant_set_power,
use conexant power settings for auto model

----------------------
hda_codec.c
----------------------
+ hda_set_power_state(codec, AC_PWRST_D0);
(when on battery power) power up the AFG to avoid the soft click noise when 
rebooting

Would you rewrite it into the "upstream style"?
Thank you.

** Patch added: "patch against dkms-hda_0.201212172004~quantal1"
   
https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/886975/+attachment/3464795/+files/lenovo-conexant.patch

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https://bugs.launchpad.net/bugs/886975

Title:
  [Thinkpad R61i/T61] Lenovo sound chip Conexant CX20549 Venice doesn't
  work correctly.

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