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ASoC: cs42l42: Don't set idle_bias_on

idle_bias_on was set because cs42l42 has a "VMID" type pseudo-midrail
supply (named FILT+), and these typically take a long time to charge.
But the driver never enabled pm_runtime so it would never have powered-
down the cs42l42 anyway.

In fact, FILT+ can charge to operating voltage within 12.5 milliseconds
of enabling HP or ADC. This time is already covered by the startup
delay of the HP/ADC.

The datasheet warning about FILT+ taking up to 1 second to charge only
applies in the special cases that either the PLL is started or
DETECT_MODE set to non-zero while both HP and ADC are off. The driver
never does either of these.

Removing idle_bias_on allows the Soundwire host controller to suspend
if there isn't a snd_soc_jack handler registered.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Signed-off-by: Stefan Binding <sbinding@opensource.cirrus.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20230127165111.3010960-8-sbinding@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

authored by

Richard Fitzgerald and committed by
Mark Brown
e0bd53a4 90f6a2a2

-1
-1
sound/soc/codecs/cs42l42.c
··· 597 597 .num_dapm_routes = ARRAY_SIZE(cs42l42_audio_map), 598 598 .controls = cs42l42_snd_controls, 599 599 .num_controls = ARRAY_SIZE(cs42l42_snd_controls), 600 - .idle_bias_on = 1, 601 600 .endianness = 1, 602 601 }; 603 602 EXPORT_SYMBOL_NS_GPL(cs42l42_soc_component, SND_SOC_CS42L42_CORE);