To reduce the risk of speaker damage the PA gain needs to be limited on machines like the Lenovo Thinkpad X13s until we have active speaker protection in place.
Limit the gain to the current default setting provided by the UCM configuration which most user have so far been using (due to a bug in the configuration files which prevented hardware volume control [1]).
Included is also a related fix for the LPASS WSA macro driver, which was changing the digital gain setting behind the back of user space and which can result in excessive (or too low) digital gain.
There are further Qualcomm codec drivers that similarly appear to manipulate various gain settings, but on closer inspection it turns out that they only write back the current settings. Tests reveal that these writes are indeed needed for any prior updates to take effect (at least for the WSA and RX macros).
Johan
[1] https://github.com/alsa-project/alsa-ucm-conf/pull/382
Changes in v2 - keep the volume register write on power-on in lpass-wsa-macro - drop the other patches removing volume register writes on DAPM events - only drop the constant-zero gain offsets in wcd9335
Johan Hovold (3): ASoC: qcom: sc8280xp: limit speaker volumes ASoC: codecs: lpass-wsa-macro: fix compander volume hack ASoC: codecs: wcd9335: drop unused gain hack remnant
sound/soc/codecs/lpass-wsa-macro.c | 7 ------- sound/soc/codecs/wcd9335.c | 4 ---- sound/soc/qcom/sc8280xp.c | 8 +++++--- 3 files changed, 5 insertions(+), 14 deletions(-)