hwmon: (core) Add support for currX_emergency and inX_[l]emergency attributes

Some hardware monitoring chips support three alarm levels for current and
voltage high limits, and three alarm levels for voltage low limits.
Add support for currX_emergency, inX_emergency, and inX_lemergency
attributes together with the appropriate alarm attributes to support such
chips.

Cc: Manaf Meethalavalappu Pallikunhi <manaf.pallikunhi@oss.qualcomm.com>
Tested-by: Manaf Meethalavalappu Pallikunhi <manaf.pallikunhi@oss.qualcomm.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://patch.msgid.link/20260813211433.879638-1-linux@roeck-us.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Documentation/ABI/testing/sysfs-class-hwmon

@@ -61,6 +61,18 @@ Description:
 		take drastic action such as power down or reset. At the very
 		least, it should report a fault.
 
+What:		/sys/class/hwmon/hwmonX/inY_lemergency
+Description:
+		Voltage emergency min value.
+
+		Unit: millivolt
+
+		RW
+
+		If voltage drops to or below this limit, the system is
+		expected to take drastic action such as immediate power
+		down or reset. At the very least, it should report a fault.
+
 What:		/sys/class/hwmon/hwmonX/inY_max
 Description:
 		Voltage max value.
@@ -81,6 +93,18 @@ Description:
 		take drastic action such as power down or reset. At the very
 		least, it should report a fault.
 
+What:		/sys/class/hwmon/hwmonX/inY_emergency
+Description:
+		Voltage emergency max value.
+
+		Unit: millivolt
+
+		RW
+
+		If voltage reaches or exceeds this limit, the system is expected
+		to take drastic action such as immediate power down or reset.
+		At the very least, it should report a fault.
+
 What:		/sys/class/hwmon/hwmonX/inY_input
 Description:
 		Voltage input value.
@@ -647,6 +671,18 @@ Description:
 
 		RW
 
+What:		/sys/class/hwmon/hwmonX/currY_emergency
+Description:
+		Current emergency high value.
+
+		Unit: milliampere
+
+		RW
+
+		If a current reaches or exceeds this limit, the system is
+		expected to take drastic action such as immediate power down
+		or reset. At the very least, it should report a fault.
+
 What:		/sys/class/hwmon/hwmonX/currY_input
 Description:
 		Current input value

Documentation/hwmon/sysfs-interface.rst

@@ -121,12 +121,18 @@ Voltages
 `in[0-*]_lcrit`
 		Voltage critical min value.
 
+`in[0-*]_lemergency`
+		Voltage emergency min value.
+
 `in[0-*]_max`
 		Voltage max value.
 
 `in[0-*]_crit`
 		Voltage critical max value.
 
+`in[0-*]_emergency`
+		Voltage emergency max value.
+
 `in[0-*]_input`
 		Voltage input value.
 
@@ -332,6 +338,9 @@ Currents
 `curr[1-*]_crit`
 		Current critical high value.
 
+`curr[1-*]_emergency`
+		Current emergency high value.
+
 `curr[1-*]_input`
 		Current input value.
 
@@ -527,12 +536,15 @@ implementation.
 +-------------------------------+-----------------------+
 | **`in[0-*]_min_alarm`,	| Limit alarm		|
 | `in[0-*]_max_alarm`,		|			|
+| `in[0-*]_lemergency_alarm`,	|			|
 | `in[0-*]_lcrit_alarm`,	|   - 0: no alarm	|
 | `in[0-*]_crit_alarm`,		|   - 1: alarm		|
+| `in[0-*]_emergency_alarm`,	|			|
 | `curr[1-*]_min_alarm`,	|			|
 | `curr[1-*]_max_alarm`,	| RO			|
 | `curr[1-*]_lcrit_alarm`,	|			|
 | `curr[1-*]_crit_alarm`,	|			|
+| `curr[1-*]_emergency_alarm`,	|			|
 | `power[1-*]_cap_alarm`,	|			|
 | `power[1-*]_max_alarm`,	|			|
 | `power[1-*]_crit_alarm`,	|			|

drivers/hwmon/hwmon.c

@@ -625,6 +625,8 @@ static const char * const hwmon_in_attr_templates[] = {
 	[hwmon_in_max] = "in%d_max",
 	[hwmon_in_lcrit] = "in%d_lcrit",
 	[hwmon_in_crit] = "in%d_crit",
+	[hwmon_in_lemergency] = "in%d_lemergency",
+	[hwmon_in_emergency] = "in%d_emergency",
 	[hwmon_in_average] = "in%d_average",
 	[hwmon_in_lowest] = "in%d_lowest",
 	[hwmon_in_highest] = "in%d_highest",
@@ -635,6 +637,8 @@ static const char * const hwmon_in_attr_templates[] = {
 	[hwmon_in_max_alarm] = "in%d_max_alarm",
 	[hwmon_in_lcrit_alarm] = "in%d_lcrit_alarm",
 	[hwmon_in_crit_alarm] = "in%d_crit_alarm",
+	[hwmon_in_lemergency_alarm] = "in%d_lemergency_alarm",
+	[hwmon_in_emergency_alarm] = "in%d_emergency_alarm",
 	[hwmon_in_rated_min] = "in%d_rated_min",
 	[hwmon_in_rated_max] = "in%d_rated_max",
 	[hwmon_in_beep] = "in%d_beep",
@@ -648,6 +652,7 @@ static const char * const hwmon_curr_attr_templates[] = {
 	[hwmon_curr_max] = "curr%d_max",
 	[hwmon_curr_lcrit] = "curr%d_lcrit",
 	[hwmon_curr_crit] = "curr%d_crit",
+	[hwmon_curr_emergency] = "curr%d_emergency",
 	[hwmon_curr_average] = "curr%d_average",
 	[hwmon_curr_lowest] = "curr%d_lowest",
 	[hwmon_curr_highest] = "curr%d_highest",
@@ -658,6 +663,7 @@ static const char * const hwmon_curr_attr_templates[] = {
 	[hwmon_curr_max_alarm] = "curr%d_max_alarm",
 	[hwmon_curr_lcrit_alarm] = "curr%d_lcrit_alarm",
 	[hwmon_curr_crit_alarm] = "curr%d_crit_alarm",
+	[hwmon_curr_emergency_alarm] = "curr%d_emergency_alarm",
 	[hwmon_curr_rated_min] = "curr%d_rated_min",
 	[hwmon_curr_rated_max] = "curr%d_rated_max",
 	[hwmon_curr_beep] = "curr%d_beep",

include/linux/hwmon.h

@@ -134,6 +134,8 @@ enum hwmon_in_attributes {
 	hwmon_in_max,
 	hwmon_in_lcrit,
 	hwmon_in_crit,
+	hwmon_in_lemergency,
+	hwmon_in_emergency,
 	hwmon_in_average,
 	hwmon_in_lowest,
 	hwmon_in_highest,
@@ -144,6 +146,8 @@ enum hwmon_in_attributes {
 	hwmon_in_max_alarm,
 	hwmon_in_lcrit_alarm,
 	hwmon_in_crit_alarm,
+	hwmon_in_lemergency_alarm,
+	hwmon_in_emergency_alarm,
 	hwmon_in_rated_min,
 	hwmon_in_rated_max,
 	hwmon_in_beep,
@@ -156,6 +160,8 @@ enum hwmon_in_attributes {
 #define HWMON_I_MAX		BIT(hwmon_in_max)
 #define HWMON_I_LCRIT		BIT(hwmon_in_lcrit)
 #define HWMON_I_CRIT		BIT(hwmon_in_crit)
+#define HWMON_I_LEMERGENCY	BIT(hwmon_in_lemergency)
+#define HWMON_I_EMERGENCY	BIT(hwmon_in_emergency)
 #define HWMON_I_AVERAGE		BIT(hwmon_in_average)
 #define HWMON_I_LOWEST		BIT(hwmon_in_lowest)
 #define HWMON_I_HIGHEST		BIT(hwmon_in_highest)
@@ -166,6 +172,8 @@ enum hwmon_in_attributes {
 #define HWMON_I_MAX_ALARM	BIT(hwmon_in_max_alarm)
 #define HWMON_I_LCRIT_ALARM	BIT(hwmon_in_lcrit_alarm)
 #define HWMON_I_CRIT_ALARM	BIT(hwmon_in_crit_alarm)
+#define HWMON_I_LEMERGENCY_ALARM BIT(hwmon_in_lemergency_alarm)
+#define HWMON_I_EMERGENCY_ALARM	BIT(hwmon_in_emergency_alarm)
 #define HWMON_I_RATED_MIN	BIT(hwmon_in_rated_min)
 #define HWMON_I_RATED_MAX	BIT(hwmon_in_rated_max)
 #define HWMON_I_BEEP		BIT(hwmon_in_beep)
@@ -178,6 +186,7 @@ enum hwmon_curr_attributes {
 	hwmon_curr_max,
 	hwmon_curr_lcrit,
 	hwmon_curr_crit,
+	hwmon_curr_emergency,
 	hwmon_curr_average,
 	hwmon_curr_lowest,
 	hwmon_curr_highest,
@@ -188,6 +197,7 @@ enum hwmon_curr_attributes {
 	hwmon_curr_max_alarm,
 	hwmon_curr_lcrit_alarm,
 	hwmon_curr_crit_alarm,
+	hwmon_curr_emergency_alarm,
 	hwmon_curr_rated_min,
 	hwmon_curr_rated_max,
 	hwmon_curr_beep,
@@ -199,6 +209,7 @@ enum hwmon_curr_attributes {
 #define HWMON_C_MAX		BIT(hwmon_curr_max)
 #define HWMON_C_LCRIT		BIT(hwmon_curr_lcrit)
 #define HWMON_C_CRIT		BIT(hwmon_curr_crit)
+#define HWMON_C_EMERGENCY	BIT(hwmon_curr_emergency)
 #define HWMON_C_AVERAGE		BIT(hwmon_curr_average)
 #define HWMON_C_LOWEST		BIT(hwmon_curr_lowest)
 #define HWMON_C_HIGHEST		BIT(hwmon_curr_highest)
@@ -209,6 +220,7 @@ enum hwmon_curr_attributes {
 #define HWMON_C_MAX_ALARM	BIT(hwmon_curr_max_alarm)
 #define HWMON_C_LCRIT_ALARM	BIT(hwmon_curr_lcrit_alarm)
 #define HWMON_C_CRIT_ALARM	BIT(hwmon_curr_crit_alarm)
+#define HWMON_C_EMERGENCY_ALARM	BIT(hwmon_curr_emergency_alarm)
 #define HWMON_C_RATED_MIN	BIT(hwmon_curr_rated_min)
 #define HWMON_C_RATED_MAX	BIT(hwmon_curr_rated_max)
 #define HWMON_C_BEEP		BIT(hwmon_curr_beep)