ASoC: cs42l42: make HSBIAS_SENSE_EN optional

HSBIAS_SENSE_EN configures HSBIAS output current sense through
the external 2.21-k resistor. HSBIAS_SENSE is hardware feature to reduce
the potential pop noise during the headset plug out slowly. But on some
platforms ESD voltage will affect it causing test to fail, especially
with CTIA headset type. For different hardware setups, a designer might
want to tweak default behavior.

Signed-off-by: Vitaly Rodionov <vitalyr@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20210511145220.125760-1-vitalyr@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: Vitaly Rodionov

Documentation/devicetree/bindings/sound/cs42l42.txt

@@ -81,6 +81,13 @@ Optional properties:
   < x1 x2 x3 x4 >
   Default = < 15 8 4 1>
 
+  - cirrus,hs-bias-sense-disable: This is boolean property. If present the
+  HSBIAS sense is disabled. Configures HSBIAS output current sense through
+  the external 2.21-k resistor. HSBIAS_SENSE is hardware feature to reduce
+  the potential pop noise during the headset plug out slowly. But on some
+  platforms ESD voltage will affect it causing test to fail, especially
+  with CTIA headset type. For different hardware setups, a designer might
+  want to tweak default behavior.
 
 Example:
 

sound/soc/codecs/cs42l42.c

@@ -1033,7 +1033,7 @@ static void cs42l42_process_hs_type_detect(struct cs42l42_private *cs42l42)
 			CS42L42_AUTO_HSBIAS_HIZ_MASK |
 			CS42L42_TIP_SENSE_EN_MASK |
 			CS42L42_HSBIAS_SENSE_TRIP_MASK,
-			(1 << CS42L42_HSBIAS_SENSE_EN_SHIFT) |
+			(cs42l42->hs_bias_sense_en << CS42L42_HSBIAS_SENSE_EN_SHIFT) |
 			(1 << CS42L42_AUTO_HSBIAS_HIZ_SHIFT) |
 			(0 << CS42L42_TIP_SENSE_EN_SHIFT) |
 			(3 << CS42L42_HSBIAS_SENSE_TRIP_SHIFT));
@@ -1808,6 +1808,11 @@ static int cs42l42_handle_device_data(struct device *dev,
 			(cs42l42->hs_bias_ramp_rate <<
 			CS42L42_HSBIAS_RAMP_SHIFT));
 
+	if (device_property_read_bool(dev, "cirrus,hs-bias-sense-disable"))
+		cs42l42->hs_bias_sense_en = 0;
+	else
+		cs42l42->hs_bias_sense_en = 1;
+
 	return 0;
 }
 

sound/soc/codecs/cs42l42.h

@@ -787,6 +787,7 @@ struct  cs42l42_private {
 	u8 bias_thresholds[CS42L42_NUM_BIASES];
 	u8 hs_bias_ramp_rate;
 	u8 hs_bias_ramp_time;
+	u8 hs_bias_sense_en;
 	u8 stream_use;
 };