[PATCH 1/4] power: supply: Add sysfs entry for liquid detection control

[Waqar Hameed]

There are devices that have built-in liquid detection. For example to
mitigate corrosion caused by moisture in a port. In order to be able to
configure such devices, add sysfs entry for controlling a device's
liquid detection.

Signed-off-by: Waqar Hameed <waqar.hameed@xxxxxxxx>
---
 Documentation/ABI/testing/sysfs-class-power | 19 +++++++++++++++++++
 drivers/power/supply/power_supply_sysfs.c   |  8 ++++++++
 include/linux/power_supply.h                |  8 ++++++++
 3 files changed, 35 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-class-power b/Documentation/ABI/testing/sysfs-class-power
index 671786d4600de..a98e6b2a75fbc 100644
--- a/Documentation/ABI/testing/sysfs-class-power
+++ b/Documentation/ABI/testing/sysfs-class-power
@@ -619,6 +619,25 @@ Description:
 		"Ship"    (4) Ship mode.
 		============= ==================================
 
+What:		/sys/class/power_supply/<supply_name>/liquid_detection_control
+Date:		October 2026
+Contact:	linux-pm@xxxxxxxxxxxxxxx
+Description:
+		Devices can have built-in liquid detection functionality. This
+		can for example be used to mitigate port corrosion caused by
+		moisture. This entry controls a device's liquid detection.
+
+		Access: Read, Write
+
+		Valid values:
+
+		============= ===============================================
+		"Unknown" (0) Unknown state.
+		"Off"     (1) Liquid detection is disabled.
+		"Auto"    (2) Liquid detection is checked periodically.
+		"Once"    (3) Check for liquid once then transition to "Off".
+		============= ===============================================
+
 **USB Properties**
 
 What:		/sys/class/power_supply/<supply_name>/input_current_limit
diff --git a/drivers/power/supply/power_supply_sysfs.c b/drivers/power/supply/power_supply_sysfs.c
index 9704557ffe1dc..661b42adf6efc 100644
--- a/drivers/power/supply/power_supply_sysfs.c
+++ b/drivers/power/supply/power_supply_sysfs.c
@@ -160,6 +160,13 @@ static const char *const POWER_SUPPLY_LOAD_SWITCH_TEXT[] = {
 	[POWER_SUPPLY_LOAD_SWITCH_SHIP]	   = "Ship",
 };
 
+static const char *const POWER_SUPPLY_LIQUID_DETECTION_CONTROL_TEXT[] = {
+	[POWER_SUPPLY_LIQUID_DETECTION_CONTROL_UNKNOWN] = "Unknown",
+	[POWER_SUPPLY_LIQUID_DETECTION_CONTROL_OFF]	= "Off",
+	[POWER_SUPPLY_LIQUID_DETECTION_CONTROL_AUTO]	= "Auto",
+	[POWER_SUPPLY_LIQUID_DETECTION_CONTROL_ONCE]	= "Once",
+};
+
 static struct power_supply_attr power_supply_attrs[] __ro_after_init = {
 	/* Properties of type `int' */
 	POWER_SUPPLY_ENUM_ATTR(STATUS),
@@ -240,6 +247,7 @@ static struct power_supply_attr power_supply_attrs[] __ro_after_init = {
 	POWER_SUPPLY_ATTR(INTERNAL_RESISTANCE),
 	POWER_SUPPLY_ATTR(STATE_OF_HEALTH),
 	POWER_SUPPLY_ENUM_ATTR(LOAD_SWITCH),
+	POWER_SUPPLY_ENUM_ATTR(LIQUID_DETECTION_CONTROL),
 	/* Properties of type `const char *' */
 	POWER_SUPPLY_ATTR(MODEL_NAME),
 	POWER_SUPPLY_ATTR(MANUFACTURER),
diff --git a/include/linux/power_supply.h b/include/linux/power_supply.h
index cce61137aef4d..8e5bbdfebe794 100644
--- a/include/linux/power_supply.h
+++ b/include/linux/power_supply.h
@@ -112,6 +112,13 @@ enum {
 	POWER_SUPPLY_LOAD_SWITCH_SHIP,
 };
 
+enum {
+	POWER_SUPPLY_LIQUID_DETECTION_CONTROL_UNKNOWN = 0,
+	POWER_SUPPLY_LIQUID_DETECTION_CONTROL_OFF,
+	POWER_SUPPLY_LIQUID_DETECTION_CONTROL_AUTO,
+	POWER_SUPPLY_LIQUID_DETECTION_CONTROL_ONCE,
+};
+
 enum power_supply_property {
 	/* Properties of type `int' */
 	POWER_SUPPLY_PROP_STATUS = 0,
@@ -191,6 +198,7 @@ enum power_supply_property {
 	POWER_SUPPLY_PROP_INTERNAL_RESISTANCE,
 	POWER_SUPPLY_PROP_STATE_OF_HEALTH,
 	POWER_SUPPLY_PROP_LOAD_SWITCH,
+	POWER_SUPPLY_PROP_LIQUID_DETECTION_CONTROL,
 	/* Properties of type `const char *' */
 	POWER_SUPPLY_PROP_MODEL_NAME,
 	POWER_SUPPLY_PROP_MANUFACTURER,
-- 
2.43.0