[PATCH] ASoC: cs42l42: make HSBIAS_SENSE_EN optional

[Lucas Tanure]

From: Vitaly Rodionov <vitalyr at opensource.cirrus.com>

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 at opensource.cirrus.com>
Signed-off-by: Lucas Tanure <tanureal at opensource.cirrus.com>
---
 .../devicetree/bindings/sound/cs42l42.txt     | 10 ++++++++++
 include/dt-bindings/sound/cs42l42.h           |  3 +++
 sound/soc/codecs/cs42l42.c                    | 20 ++++++++++++++++++-
 sound/soc/codecs/cs42l42.h                    |  1 +
 4 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/sound/cs42l42.txt b/Documentation/devicetree/bindings/sound/cs42l42.txt
index 7dfaa2ab906f..e75f191d2945 100644
--- a/Documentation/devicetree/bindings/sound/cs42l42.txt
+++ b/Documentation/devicetree/bindings/sound/cs42l42.txt
@@ -81,6 +81,16 @@ Optional properties:
   < x1 x2 x3 x4 >
   Default = < 15 8 4 1>
 
+  - cirrus,hs-bias-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.
+
+  0 - disabled
+  1 - enabled
+  Default = 1
 
 Example:
 
diff --git a/include/dt-bindings/sound/cs42l42.h b/include/dt-bindings/sound/cs42l42.h
index f25d83c6188b..788e1598b15f 100644
--- a/include/dt-bindings/sound/cs42l42.h
+++ b/include/dt-bindings/sound/cs42l42.h
@@ -66,4 +66,7 @@
 #define CS42L42_HSBIAS_RAMP_TIME2			90
 #define CS42L42_HSBIAS_RAMP_TIME3			170
 
+#define CS42L42_HSBIAS_SENSE_ON  1
+#define CS42L42_HSBIAS_SENSE_OFF 0
+
 #endif /* __DT_CS42L42_H */
diff --git a/sound/soc/codecs/cs42l42.c b/sound/soc/codecs/cs42l42.c
index d9f8da7a68d0..139245c6b720 100644
--- a/sound/soc/codecs/cs42l42.c
+++ b/sound/soc/codecs/cs42l42.c
@@ -1032,7 +1032,7 @@ 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));
@@ -1807,6 +1807,24 @@ static int cs42l42_handle_device_data(struct device *dev,
 			(cs42l42->hs_bias_ramp_rate <<
 			CS42L42_HSBIAS_RAMP_SHIFT));
 
+	ret = device_property_read_u32(dev, "cirrus,hs-bias-sense-en", &val);
+	if (!ret) {
+		switch (val) {
+		case CS42L42_HSBIAS_SENSE_OFF:
+		case CS42L42_HSBIAS_SENSE_ON:
+			cs42l42->hs_bias_sense_en = val;
+			break;
+		default:
+			dev_err(dev,
+				"Wrong cirrus,hs-bias-sense-en DT value %d\n",
+				val);
+			cs42l42->hs_bias_sense_en = CS42L42_HSBIAS_SENSE_ON;
+			break;
+		}
+	} else {
+		cs42l42->hs_bias_sense_en = CS42L42_HSBIAS_SENSE_ON;
+	}
+
 	return 0;
 }
 
diff --git a/sound/soc/codecs/cs42l42.h b/sound/soc/codecs/cs42l42.h
index 2e0d3836bd7e..24f7be228d5f 100644
--- a/sound/soc/codecs/cs42l42.h
+++ b/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;
 };
 
-- 
2.31.1