summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--Documentation/hwmon/hp-wmi-sensors.rst140
-rw-r--r--Documentation/hwmon/index.rst1
-rw-r--r--MAINTAINERS7
-rw-r--r--drivers/hwmon/Kconfig12
-rw-r--r--drivers/hwmon/Makefile1
-rw-r--r--drivers/hwmon/hp-wmi-sensors.c2015
6 files changed, 2176 insertions, 0 deletions
diff --git a/Documentation/hwmon/hp-wmi-sensors.rst b/Documentation/hwmon/hp-wmi-sensors.rst
new file mode 100644
index 000000000000..a6bca9aecdde
--- /dev/null
+++ b/Documentation/hwmon/hp-wmi-sensors.rst
@@ -0,0 +1,140 @@
+.. SPDX-License-Identifier: GPL-2.0-or-later
+
+.. include:: <isonum.txt>
+
+===========================
+Linux HP WMI Sensors Driver
+===========================
+
+:Copyright: |copy| 2023 James Seo <james@equiv.tech>
+
+Description
+===========
+
+Hewlett-Packard (and some HP Compaq) business-class computers report hardware
+monitoring information via Windows Management Instrumentation (WMI).
+This driver exposes that information to the Linux hwmon subsystem, allowing
+userspace utilities like ``sensors`` to gather numeric sensor readings.
+
+sysfs interface
+===============
+
+When the driver is loaded, it discovers the sensors available on the
+system and creates the following sysfs attributes as necessary within
+``/sys/class/hwmon/hwmon[X]``:
+
+(``[X]`` is some number that depends on other system components.)
+
+======================= ======= ===================================
+Name Perm Description
+======================= ======= ===================================
+``curr[X]_input`` RO Current in milliamperes (mA).
+``curr[X]_label`` RO Current sensor label.
+``fan[X]_input`` RO Fan speed in RPM.
+``fan[X]_label`` RO Fan sensor label.
+``fan[X]_fault`` RO Fan sensor fault indicator.
+``fan[X]_alarm`` RO Fan sensor alarm indicator.
+``in[X]_input`` RO Voltage in millivolts (mV).
+``in[X]_label`` RO Voltage sensor label.
+``temp[X]_input`` RO Temperature in millidegrees Celsius
+ (m\ |deg|\ C).
+``temp[X]_label`` RO Temperature sensor label.
+``temp[X]_fault`` RO Temperature sensor fault indicator.
+``temp[X]_alarm`` RO Temperature sensor alarm indicator.
+``intrusion[X]_alarm`` RW Chassis intrusion alarm indicator.
+======================= ======= ===================================
+
+``fault`` attributes
+ Reading ``1`` instead of ``0`` as the ``fault`` attribute for a sensor
+ indicates that it has encountered some issue during operation such that
+ measurements from it should not be trusted. If a sensor with the fault
+ condition recovers later, reading this attribute will return ``0`` again.
+
+``alarm`` attributes
+ Reading ``1`` instead of ``0`` as the ``alarm`` attribute for a sensor
+ indicates that one of the following has occurred, depending on its type:
+
+ - ``fan``: The fan has stalled or has been disconnected while running.
+ - ``temp``: The sensor reading has reached a critical threshold.
+ The exact threshold is system-dependent.
+ - ``intrusion``: The system's chassis has been opened.
+
+ After ``1`` is read from an ``alarm`` attribute, the attribute resets itself
+ and returns ``0`` on subsequent reads. As an exception, an
+ ``intrusion[X]_alarm`` can only be manually reset by writing ``0`` to it.
+
+debugfs interface
+=================
+
+.. warning:: The debugfs interface is subject to change without notice
+ and is only available when the kernel is compiled with
+ ``CONFIG_DEBUG_FS`` defined.
+
+The standard hwmon interface in sysfs exposes sensors of several common types
+that are connected as of driver initialization. However, there are usually
+other sensors in WMI that do not meet these criteria. In addition, a number of
+system-dependent "platform events objects" used for ``alarm`` attributes may
+be present. A debugfs interface is therefore provided for read-only access to
+all available HP WMI sensors and platform events objects.
+
+``/sys/kernel/debug/hp-wmi-sensors-[X]/sensor``
+contains one numbered entry per sensor with the following attributes:
+
+=============================== =======================================
+Name Example
+=============================== =======================================
+``name`` ``CPU0 Fan``
+``description`` ``Reports CPU0 fan speed``
+``sensor_type`` ``12``
+``other_sensor_type`` (an empty string)
+``operational_status`` ``2``
+``possible_states`` ``Normal,Caution,Critical,Not Present``
+``current_state`` ``Normal``
+``base_units`` ``19``
+``unit_modifier`` ``0``
+``current_reading`` ``1008``
+``rate_units`` ``0`` (only exists on some systems)
+=============================== =======================================
+
+If platform events objects are available,
+``/sys/kernel/debug/hp-wmi-sensors-[X]/platform_events``
+contains one numbered entry per object with the following attributes:
+
+=============================== ====================
+Name Example
+=============================== ====================
+``name`` ``CPU0 Fan Stall``
+``description`` ``CPU0 Fan Speed``
+``source_namespace`` ``root\wmi``
+``source_class`` ``HPBIOS_BIOSEvent``
+``category`` ``3``
+``possible_severity`` ``25``
+``possible_status`` ``5``
+=============================== ====================
+
+These represent the properties of the underlying ``HPBIOS_BIOSNumericSensor``
+and ``HPBIOS_PlatformEvents`` WMI objects, which vary between systems.
+See [#]_ for more details and Managed Object Format (MOF) definitions.
+
+Known issues and limitations
+============================
+
+- If the existing hp-wmi driver for non-business-class HP systems is already
+ loaded, ``alarm`` attributes will be unavailable even on systems that
+ support them. This is because the same WMI event GUID used by this driver
+ for ``alarm`` attributes is used on those systems for e.g. laptop hotkeys.
+- Dubious sensor hardware and inconsistent BIOS WMI implementations have been
+ observed to cause inaccurate readings and peculiar behavior, such as alarms
+ failing to occur or occurring only once per boot.
+- Only temperature, fan speed, and intrusion sensor types have been seen in
+ the wild so far. Support for voltage and current sensors is therefore
+ provisional.
+- Although HP WMI sensors may claim to be of any type, any oddball sensor
+ types unknown to hwmon will not be supported.
+
+References
+==========
+
+.. [#] Hewlett-Packard Development Company, L.P.,
+ "HP Client Management Interface Technical White Paper", 2005. [Online].
+ Available: https://h20331.www2.hp.com/hpsub/downloads/cmi_whitepaper.pdf
diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index b3af03214b3e..042e1cf9501b 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -77,6 +77,7 @@ Hardware Monitoring Kernel Drivers
gl518sm
gxp-fan-ctrl
hih6130
+ hp-wmi-sensors
ibmaem
ibm-cffps
ibmpowernv
diff --git a/MAINTAINERS b/MAINTAINERS
index 9c300a3ebb66..e5b7c3ee83ba 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9425,6 +9425,13 @@ L: platform-driver-x86@vger.kernel.org
S: Orphan
F: drivers/platform/x86/hp/tc1100-wmi.c
+HP WMI HARDWARE MONITOR DRIVER
+M: James Seo <james@equiv.tech>
+L: linux-hwmon@vger.kernel.org
+S: Maintained
+F: Documentation/hwmon/hp-wmi-sensors.rst
+F: drivers/hwmon/hp-wmi-sensors.c
+
HPET: High Precision Event Timers driver
M: Clemens Ladisch <clemens@ladisch.de>
S: Maintained
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index c52e44a393e9..307477b8a371 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -2421,6 +2421,18 @@ config SENSORS_ASUS_EC
This driver can also be built as a module. If so, the module
will be called asus_ec_sensors.
+config SENSORS_HP_WMI
+ tristate "HP WMI Sensors"
+ depends on ACPI_WMI
+ help
+ If you say yes here you get support for the ACPI hardware monitoring
+ interface found in HP (and some HP Compaq) business-class computers.
+ Available sensors vary between systems. Temperature and fan speed
+ sensors are the most common.
+
+ This driver can also be built as a module. If so, the module
+ will be called hp_wmi_sensors.
+
endif # ACPI
endif # HWMON
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 8a8021f9ca9e..3f4b0fda0998 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -11,6 +11,7 @@ obj-$(CONFIG_SENSORS_ACPI_POWER) += acpi_power_meter.o
obj-$(CONFIG_SENSORS_ATK0110) += asus_atk0110.o
obj-$(CONFIG_SENSORS_ASUS_EC) += asus-ec-sensors.o
obj-$(CONFIG_SENSORS_ASUS_WMI) += asus_wmi_sensors.o
+obj-$(CONFIG_SENSORS_HP_WMI) += hp-wmi-sensors.o
# Native drivers
# asb100, then w83781d go first, as they can override other drivers' addresses.
diff --git a/drivers/hwmon/hp-wmi-sensors.c b/drivers/hwmon/hp-wmi-sensors.c
new file mode 100644
index 000000000000..7218945bd03f
--- /dev/null
+++ b/drivers/hwmon/hp-wmi-sensors.c
@@ -0,0 +1,2015 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * hwmon driver for HP (and some HP Compaq) business-class computers that
+ * report numeric sensor data via Windows Management Instrumentation (WMI).
+ *
+ * Copyright (C) 2023 James Seo <james@equiv.tech>
+ *
+ * References:
+ * [1] Hewlett-Packard Development Company, L.P.,
+ * "HP Client Management Interface Technical White Paper", 2005. [Online].
+ * Available: https://h20331.www2.hp.com/hpsub/downloads/cmi_whitepaper.pdf
+ * [2] Hewlett-Packard Development Company, L.P.,
+ * "HP Retail Manageability", 2012. [Online].
+ * Available: http://h10032.www1.hp.com/ctg/Manual/c03291135.pdf
+ * [3] Linux Hardware Project, A. Ponomarenko et al.,
+ * "linuxhw/ACPI - Collect ACPI table dumps", 2018. [Online].
+ * Available: https://github.com/linuxhw/ACPI
+ * [4] P. Rohár, "bmfdec - Decompile binary MOF file (BMF) from WMI buffer",
+ * 2017. [Online]. Available: https://github.com/pali/bmfdec
+ */
+
+#include <linux/acpi.h>
+#include <linux/debugfs.h>
+#include <linux/hwmon.h>
+#include <linux/jiffies.h>
+#include <linux/mutex.h>
+#include <linux/units.h>
+#include <linux/wmi.h>
+
+#define HP_WMI_EVENT_NAMESPACE "root\\WMI"
+#define HP_WMI_EVENT_CLASS "HPBIOS_BIOSEvent"
+#define HP_WMI_EVENT_GUID "95F24279-4D7B-4334-9387-ACCDC67EF61C"
+#define HP_WMI_NUMERIC_SENSOR_GUID "8F1F6435-9F42-42C8-BADC-0E9424F20C9A"
+#define HP_WMI_PLATFORM_EVENTS_GUID "41227C2D-80E1-423F-8B8E-87E32755A0EB"
+
+/* Patterns for recognizing sensors and matching events to channels. */
+
+#define HP_WMI_PATTERN_SYS_TEMP "Chassis Thermal Index"
+#define HP_WMI_PATTERN_SYS_TEMP2 "System Ambient Temperature"
+#define HP_WMI_PATTERN_CPU_TEMP "CPU Thermal Index"
+#define HP_WMI_PATTERN_CPU_TEMP2 "CPU Temperature"
+#define HP_WMI_PATTERN_TEMP_SENSOR "Thermal Index"
+#define HP_WMI_PATTERN_TEMP_ALARM "Thermal Critical"
+#define HP_WMI_PATTERN_INTRUSION_ALARM "Hood Intrusion"
+#define HP_WMI_PATTERN_FAN_ALARM "Stall"
+#define HP_WMI_PATTERN_TEMP "Temperature"
+#define HP_WMI_PATTERN_CPU "CPU"
+
+/* These limits are arbitrary. The WMI implementation may vary by system. */
+
+#define HP_WMI_MAX_STR_SIZE 128U
+#define HP_WMI_MAX_PROPERTIES 32U
+#define HP_WMI_MAX_INSTANCES 32U
+
+enum hp_wmi_type {
+ HP_WMI_TYPE_OTHER = 1,
+ HP_WMI_TYPE_TEMPERATURE = 2,
+ HP_WMI_TYPE_VOLTAGE = 3,
+ HP_WMI_TYPE_CURRENT = 4,
+ HP_WMI_TYPE_AIR_FLOW = 12,
+ HP_WMI_TYPE_INTRUSION = 0xabadb01, /* Custom. */
+};
+
+enum hp_wmi_category {
+ HP_WMI_CATEGORY_SENSOR = 3,
+};
+
+enum hp_wmi_severity {
+ HP_WMI_SEVERITY_UNKNOWN = 0,
+ HP_WMI_SEVERITY_OK = 5,
+ HP_WMI_SEVERITY_DEGRADED_WARNING = 10,
+ HP_WMI_SEVERITY_MINOR_FAILURE = 15,
+ HP_WMI_SEVERITY_MAJOR_FAILURE = 20,
+ HP_WMI_SEVERITY_CRITICAL_FAILURE = 25,
+ HP_WMI_SEVERITY_NON_RECOVERABLE_ERROR = 30,
+};
+
+enum hp_wmi_status {
+ HP_WMI_STATUS_OK = 2,
+ HP_WMI_STATUS_DEGRADED = 3,
+ HP_WMI_STATUS_STRESSED = 4,
+ HP_WMI_STATUS_PREDICTIVE_FAILURE = 5,
+ HP_WMI_STATUS_ERROR = 6,
+ HP_WMI_STATUS_NON_RECOVERABLE_ERROR = 7,
+ HP_WMI_STATUS_NO_CONTACT = 12,
+ HP_WMI_STATUS_LOST_COMMUNICATION = 13,
+ HP_WMI_STATUS_ABORTED = 14,
+ HP_WMI_STATUS_SUPPORTING_ENTITY_IN_ERROR = 16,
+
+ /* Occurs combined with one of "OK", "Degraded", and "Error" [1]. */
+ HP_WMI_STATUS_COMPLETED = 17,
+};
+
+enum hp_wmi_units {
+ HP_WMI_UNITS_OTHER = 1,
+ HP_WMI_UNITS_DEGREES_C = 2,
+ HP_WMI_UNITS_DEGREES_F = 3,
+ HP_WMI_UNITS_DEGREES_K = 4,
+ HP_WMI_UNITS_VOLTS = 5,
+ HP_WMI_UNITS_AMPS = 6,
+ HP_WMI_UNITS_RPM = 19,
+};
+
+enum hp_wmi_property {
+ HP_WMI_PROPERTY_NAME = 0,
+ HP_WMI_PROPERTY_DESCRIPTION = 1,
+ HP_WMI_PROPERTY_SENSOR_TYPE = 2,
+ HP_WMI_PROPERTY_OTHER_SENSOR_TYPE = 3,
+ HP_WMI_PROPERTY_OPERATIONAL_STATUS = 4,
+ HP_WMI_PROPERTY_SIZE = 5,
+ HP_WMI_PROPERTY_POSSIBLE_STATES = 6,
+ HP_WMI_PROPERTY_CURRENT_STATE = 7,
+ HP_WMI_PROPERTY_BASE_UNITS = 8,
+ HP_WMI_PROPERTY_UNIT_MODIFIER = 9,
+ HP_WMI_PROPERTY_CURRENT_READING = 10,
+ HP_WMI_PROPERTY_RATE_UNITS = 11,
+};
+
+static const acpi_object_type hp_wmi_property_map[] = {
+ [HP_WMI_PROPERTY_NAME] = ACPI_TYPE_STRING,
+ [HP_WMI_PROPERTY_DESCRIPTION] = ACPI_TYPE_STRING,
+ [HP_WMI_PROPERTY_SENSOR_TYPE] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PROPERTY_OTHER_SENSOR_TYPE] = ACPI_TYPE_STRING,
+ [HP_WMI_PROPERTY_OPERATIONAL_STATUS] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PROPERTY_SIZE] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PROPERTY_POSSIBLE_STATES] = ACPI_TYPE_STRING,
+ [HP_WMI_PROPERTY_CURRENT_STATE] = ACPI_TYPE_STRING,
+ [HP_WMI_PROPERTY_BASE_UNITS] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PROPERTY_UNIT_MODIFIER] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PROPERTY_CURRENT_READING] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PROPERTY_RATE_UNITS] = ACPI_TYPE_INTEGER,
+};
+
+enum hp_wmi_platform_events_property {
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_NAME = 0,
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_DESCRIPTION = 1,
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_SOURCE_NAMESPACE = 2,
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_SOURCE_CLASS = 3,
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_CATEGORY = 4,
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_SEVERITY = 5,
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_STATUS = 6,
+};
+
+static const acpi_object_type hp_wmi_platform_events_property_map[] = {
+ [HP_WMI_PLATFORM_EVENTS_PROPERTY_NAME] = ACPI_TYPE_STRING,
+ [HP_WMI_PLATFORM_EVENTS_PROPERTY_DESCRIPTION] = ACPI_TYPE_STRING,
+ [HP_WMI_PLATFORM_EVENTS_PROPERTY_SOURCE_NAMESPACE] = ACPI_TYPE_STRING,
+ [HP_WMI_PLATFORM_EVENTS_PROPERTY_SOURCE_CLASS] = ACPI_TYPE_STRING,
+ [HP_WMI_PLATFORM_EVENTS_PROPERTY_CATEGORY] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_SEVERITY] = ACPI_TYPE_INTEGER,
+ [HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_STATUS] = ACPI_TYPE_INTEGER,
+};
+
+enum hp_wmi_event_property {
+ HP_WMI_EVENT_PROPERTY_NAME = 0,
+ HP_WMI_EVENT_PROPERTY_DESCRIPTION = 1,
+ HP_WMI_EVENT_PROPERTY_CATEGORY = 2,
+ HP_WMI_EVENT_PROPERTY_SEVERITY = 3,
+ HP_WMI_EVENT_PROPERTY_STATUS = 4,
+};
+
+static const acpi_object_type hp_wmi_event_property_map[] = {
+ [HP_WMI_EVENT_PROPERTY_NAME] = ACPI_TYPE_STRING,
+ [HP_WMI_EVENT_PROPERTY_DESCRIPTION] = ACPI_TYPE_STRING,
+ [HP_WMI_EVENT_PROPERTY_CATEGORY] = ACPI_TYPE_INTEGER,
+ [HP_WMI_EVENT_PROPERTY_SEVERITY] = ACPI_TYPE_INTEGER,
+ [HP_WMI_EVENT_PROPERTY_STATUS] = ACPI_TYPE_INTEGER,
+};
+
+static const enum hwmon_sensor_types hp_wmi_hwmon_type_map[] = {
+ [HP_WMI_TYPE_TEMPERATURE] = hwmon_temp,
+ [HP_WMI_TYPE_VOLTAGE] = hwmon_in,
+ [HP_WMI_TYPE_CURRENT] = hwmon_curr,
+ [HP_WMI_TYPE_AIR_FLOW] = hwmon_fan,
+};
+
+static const u32 hp_wmi_hwmon_attributes[hwmon_max] = {
+ [hwmon_chip] = HWMON_C_REGISTER_TZ,
+ [hwmon_temp] = HWMON_T_INPUT | HWMON_T_LABEL | HWMON_T_FAULT,
+ [hwmon_in] = HWMON_I_INPUT | HWMON_I_LABEL,
+ [hwmon_curr] = HWMON_C_INPUT | HWMON_C_LABEL,
+ [hwmon_fan] = HWMON_F_INPUT | HWMON_F_LABEL | HWMON_F_FAULT,
+ [hwmon_intrusion] = HWMON_INTRUSION_ALARM,
+};
+
+/*
+ * struct hp_wmi_numeric_sensor - a HPBIOS_BIOSNumericSensor instance
+ *
+ * Two variants of HPBIOS_BIOSNumericSensor are known. The first is specified
+ * in [1] and appears to be much more widespread. The second was discovered by
+ * decoding BMOF blobs [4], seems to be found only in some newer ZBook systems
+ * [3], and has two new properties and a slightly different property order.
+ *
+ * These differences don't matter on Windows, where WMI object properties are
+ * accessed by name. For us, supporting both variants gets ugly and hacky at
+ * times. The fun begins now; this struct is defined as per the new variant.
+ *
+ * Effective MOF definition:
+ *
+ * #pragma namespace("\\\\.\\root\\HP\\InstrumentedBIOS");
+ * class HPBIOS_BIOSNumericSensor {
+ * [read] string Name;
+ * [read] string Description;
+ * [read, ValueMap {"0","1","2","3","4","5","6","7","8","9",
+ * "10","11","12"}, Values {"Unknown","Other","Temperature",
+ * "Voltage","Current","Tachometer","Counter","Switch","Lock",
+ * "Humidity","Smoke Detection","Presence","Air Flow"}]
+ * uint32 SensorType;
+ * [read] string OtherSensorType;
+ * [read, ValueMap {"0","1","2","3","4","5","6","7","8","9",
+ * "10","11","12","13","14","15","16","17","18","..",
+ * "0x8000.."}, Values {"Unknown","Other","OK","Degraded",
+ * "Stressed","Predictive Failure","Error",
+ * "Non-Recoverable Error","Starting","Stopping","Stopped",
+ * "In Service","No Contact","Lost Communication","Aborted",
+ * "Dormant","Supporting Entity in Error","Completed",
+ * "Power Mode","DMTF Reserved","Vendor Reserved"}]
+ * uint32 OperationalStatus;
+ * [read] uint32 Size;
+ * [read] string PossibleStates[];
+ * [read] string CurrentState;
+ * [read, ValueMap {"0","1","2","3","4","5","6","7","8","9",
+ * "10","11","12","13","14","15","16","17","18","19","20",
+ * "21","22","23","24","25","26","27","28","29","30","31",
+ * "32","33","34","35","36","37","38","39","40","41","42",
+ * "43","44","45","46","47","48","49","50","51","52","53",
+ * "54","55","56","57","58","59","60","61","62","63","64",
+ * "65"}, Values {"Unknown","Other","Degrees C","Degrees F",
+ * "Degrees K","Volts","Amps","Watts","Joules","Coulombs",
+ * "VA","Nits","Lumens","Lux","Candelas","kPa","PSI",
+ * "Newtons","CFM","RPM","Hertz","Seconds","Minutes",
+ * "Hours","Days","Weeks","Mils","Inches","Feet",
+ * "Cubic Inches","Cubic Feet","Meters","Cubic Centimeters",
+ * "Cubic Meters","Liters","Fluid Ounces","Radians",
+ * "Steradians","Revolutions","Cycles","Gravities","Ounces",
+ * "Pounds","Foot-Pounds","Ounce-Inches","Gauss","Gilberts",
+ * "Henries","Farads","Ohms","Siemens","Moles","Becquerels",
+ * "PPM (parts/million)","Decibels","DbA","DbC","Grays",
+ * "Sieverts","Color Temperature Degrees K","Bits","Bytes",
+ * "Words (data)","DoubleWords","QuadWords","Percentage"}]
+ * uint32 BaseUnits;
+ * [read] sint32 UnitModifier;
+ * [read] uint32 CurrentReading;
+ * [read] uint32 RateUnits;
+ * };
+ *
+ * Effective MOF definition of old variant [1] (sans redundant info):
+ *
+ * class HPBIOS_BIOSNumericSensor {
+ * [read] string Name;
+ * [read] string Description;
+ * [read] uint32 SensorType;
+ * [read] string OtherSensorType;
+ * [read] uint32 OperationalStatus;
+ * [read] string CurrentState;
+ * [read] string PossibleStates[];
+ * [read] uint32 BaseUnits;
+ * [read] sint32 UnitModifier;
+ * [read] uint32 CurrentReading;
+ * };
+ */
+struct hp_wmi_numeric_sensor {
+ const char *name;
+ const char *description;
+ u32 sensor_type;
+ const char *other_sensor_type; /* Explains "Other" SensorType. */
+ u32 operational_status;
+ u8 size; /* Count of PossibleStates[]. */
+ const char **possible_states;
+ const char *current_state;
+ u32 base_units;
+ s32 unit_modifier;
+ u32 current_reading;
+ u32 rate_units;
+};
+
+/*
+ * struct hp_wmi_platform_events - a HPBIOS_PlatformEvents instance
+ *
+ * Instances of this object reveal the set of possible HPBIOS_BIOSEvent
+ * instances for the current system, but it may not always be present.
+ *
+ * Effective MOF definition:
+ *
+ * #pragma namespace("\\\\.\\root\\HP\\InstrumentedBIOS");
+ * class HPBIOS_PlatformEvents {
+ * [read] string Name;
+ * [read] string Description;
+ * [read] string SourceNamespace;
+ * [read] string SourceClass;
+ * [read, ValueMap {"0","1","2","3","4",".."}, Values {
+ * "Unknown","Configuration Change","Button Pressed",
+ * "Sensor","BIOS Settings","Reserved"}]
+ * uint32 Category;
+ * [read, ValueMap{"0","5","10","15","20","25","30",".."},
+ * Values{"Unknown","OK","Degraded/Warning","Minor Failure",
+ * "Major Failure","Critical Failure","Non-recoverable Error",
+ * "DMTF Reserved"}]
+ * uint32 PossibleSeverity;
+ * [read, ValueMap {"0","1","2","3","4","5","6","7","8","9",
+ * "10","11","12","13","14","15","16","17","18","..",
+ * "0x8000.."}, Values {"Unknown","Other","OK","Degraded",
+ * "Stressed","Predictive Failure","Error",
+ * "Non-Recoverable Error","Starting","Stopping","Stopped",
+ * "In Service","No Contact","Lost Communication","Aborted",
+ * "Dormant","Supporting Entity in Error","Completed",
+ * "Power Mode","DMTF Reserved","Vendor Reserved"}]
+ * uint32 PossibleStatus;
+ * };
+ */
+struct hp_wmi_platform_events {
+ const char *name;
+ const char *description;
+ const char *source_namespace;
+ const char *source_class;
+ u32 category;
+ u32 possible_severity;
+ u32 possible_status;
+};
+
+/*
+ * struct hp_wmi_event - a HPBIOS_BIOSEvent instance
+ *
+ * Effective MOF definition [1] (corrected below from original):
+ *
+ * #pragma namespace("\\\\.\\root\\WMI");
+ * class HPBIOS_BIOSEvent : WMIEvent {
+ * [read] string Name;
+ * [read] string Description;
+ * [read ValueMap {"0","1","2","3","4"}, Values {"Unknown",
+ * "Configuration Change","Button Pressed","Sensor",
+ * "BIOS Settings"}]
+ * uint32 Category;
+ * [read, ValueMap {"0","5","10","15","20","25","30"},
+ * Values {"Unknown","OK","Degraded/Warning",
+ * "Minor Failure","Major Failure","Critical Failure",
+ * "Non-recoverable Error"}]
+ * uint32 Severity;
+ * [read, ValueMap {"0","1","2","3","4","5","6","7","8",
+ * "9","10","11","12","13","14","15","16","17","18","..",
+ * "0x8000.."}, Values {"Unknown","Other","OK","Degraded",
+ * "Stressed","Predictive Failure","Error",
+ * "Non-Recoverable Error","Starting","Stopping","Stopped",
+ * "In Service","No Contact","Lost Communication","Aborted",
+ * "Dormant","Supporting Entity in Error","Completed",
+ * "Power Mode","DMTF Reserved","Vendor Reserved"}]
+ * uint32 Status;
+ * };
+ */
+struct hp_wmi_event {
+ const char *name;
+ const char *description;
+ u32 category;
+};
+
+/*
+ * struct hp_wmi_info - sensor info
+ * @nsensor: numeric sensor properties
+ * @instance: its WMI instance number
+ * @state: pointer to driver state
+ * @has_alarm: whether sensor has an alarm flag
+ * @alarm: alarm flag
+ * @type: its hwmon sensor type
+ * @cached_val: current sensor reading value, scaled for hwmon
+ * @last_updated: when these readings were last updated
+ */
+struct hp_wmi_info {
+ struct hp_wmi_numeric_sensor nsensor;
+ u8 instance;
+ void *state; /* void *: Avoid forward declaration. */
+ bool has_alarm;
+ bool alarm;
+ enum hwmon_sensor_types type;
+ long cached_val;
+ unsigned long last_updated; /* In jiffies. */
+
+};
+
+/*
+ * struct hp_wmi_sensors - driver state
+ * @wdev: pointer to the parent WMI device
+ * @info_map: sensor info structs by hwmon type and channel number
+ * @channel_count: count of hwmon channels by hwmon type
+ * @has_intrusion: whether an intrusion sensor is present
+ * @intrusion: intrusion flag
+ * @lock: mutex to lock polling WMI and changes to driver state
+ */
+struct hp_wmi_sensors {
+ struct wmi_device *wdev;
+ struct hp_wmi_info **info_map[hwmon_max];
+ u8 channel_count[hwmon_max];
+ bool has_intrusion;
+ bool intrusion;
+
+ struct mutex lock; /* Lock polling WMI and driver state changes. */
+};
+
+/* hp_wmi_strdup - devm_kstrdup, but length-limited */
+static char *hp_wmi_strdup(struct device *dev, const char *src)
+{
+ char *dst;
+ size_t len;
+
+ len = strnlen(src, HP_WMI_MAX_STR_SIZE - 1);
+
+ dst = devm_kmalloc(dev, (len + 1) * sizeof(*dst), GFP_KERNEL);
+ if (!dst)
+ return NULL;
+
+ strscpy(dst, src, len + 1);
+
+ return dst;
+}
+
+/*
+ * hp_wmi_get_wobj - poll WMI for a WMI object instance
+ * @guid: WMI object GUID
+ * @instance: WMI object instance number
+ *
+ * Returns a new WMI object instance on success, or NULL on error.
+ * Caller must kfree() the result.
+ */
+static union acpi_object *hp_wmi_get_wobj(const char *guid, u8 instance)
+{
+ struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
+ acpi_status err;
+
+ err = wmi_query_block(guid, instance, &out);
+ if (ACPI_FAILURE(err))
+ return NULL;
+
+ return out.pointer;
+}
+
+/* hp_wmi_wobj_instance_count - find count of WMI object instances */
+static u8 hp_wmi_wobj_instance_count(const char *guid)
+{
+ u8 hi = HP_WMI_MAX_INSTANCES;
+ union acpi_object *wobj;
+ u8 lo = 0;
+ u8 mid;
+
+ while (lo < hi) {
+ mid = (lo + hi) / 2;
+
+ wobj = hp_wmi_get_wobj(guid, mid);
+ if (!wobj) {
+ hi = mid;
+ continue;
+ }
+
+ lo = mid + 1;
+ kfree(wobj);
+ }
+
+ return lo;
+}
+
+static int check_wobj(const union acpi_object *wobj,
+ const acpi_object_type property_map[], int last_prop)
+{
+ acpi_object_type type = wobj->type;
+ acpi_object_type valid_type;
+ union acpi_object *elements;
+ u32 elem_count;
+ int prop;
+
+ if (type != ACPI_TYPE_PACKAGE)
+ return -EINVAL;
+
+ elem_count = wobj->package.count;
+ if (elem_count != last_prop + 1)
+ return -EINVAL;
+
+ elements = wobj->package.elements;
+ for (prop = 0; prop <= last_prop; prop++) {
+ type = elements[prop].type;
+ valid_type = property_map[prop];
+ if (type != valid_type)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int extract_acpi_value(struct device *dev,
+ union acpi_object *element,
+ acpi_object_type type,
+ u32 *out_value, char **out_string)
+{
+ switch (type) {
+ case ACPI_TYPE_INTEGER:
+ *out_value = element->integer.value;
+ break;
+
+ case ACPI_TYPE_STRING:
+ *out_string = hp_wmi_strdup(dev, strim(element->string.pointer));
+ if (!*out_string)
+ return -ENOMEM;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * check_numeric_sensor_wobj - validate a HPBIOS_BIOSNumericSensor instance
+ * @wobj: pointer to WMI object instance to check
+ * @out_size: out pointer to count of possible states
+ * @out_is_new: out pointer to whether this is a "new" variant object
+ *
+ * Returns 0 on success, or a negative error code on error.
+ */
+static int check_numeric_sensor_wobj(const union acpi_object *wobj,
+ u8 *out_size, bool *out_is_new)
+{
+ acpi_object_type type = wobj->type;
+ int prop = HP_WMI_PROPERTY_NAME;
+ acpi_object_type valid_type;
+ union acpi_object *elements;
+ u32 elem_count;
+ int last_prop;
+ bool is_new;
+ u8 count;
+ u32 j;
+ u32 i;
+
+ if (type != ACPI_TYPE_PACKAGE)
+ return -EINVAL;
+
+ /*
+ * elements is a variable-length array of ACPI objects, one for
+ * each property of the WMI object instance, except that the
+ * strings in PossibleStates[] are flattened into this array
+ * as if each individual string were a property by itself.
+ */
+ elements = wobj->package.elements;
+
+ elem_count = wobj->package.count;
+ if (elem_count <= HP_WMI_PROPERTY_SIZE ||
+ elem_count > HP_WMI_MAX_PROPERTIES)
+ return -EINVAL;
+
+ type = elements[HP_WMI_PROPERTY_SIZE].type;
+ switch (type) {
+ case ACPI_TYPE_INTEGER:
+ is_new = true;
+ last_prop = HP_WMI_PROPERTY_RATE_UNITS;
+ break;
+
+ case ACPI_TYPE_STRING:
+ is_new = false;
+ last_prop = HP_WMI_PROPERTY_CURRENT_READING;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ /*
+ * In general, the count of PossibleStates[] must be > 0.
+ * Also, the old variant lacks the Size property, so we may need to
+ * reduce the value of last_prop by 1 when doing arithmetic with it.
+ */
+ if (elem_count < last_prop - !is_new + 1)
+ return -EINVAL;
+
+ count = elem_count - (last_prop - !is_new);
+
+ for (i = 0; i < elem_count && prop <= last_prop; i++, prop++) {
+ type = elements[i].type;
+ valid_type = hp_wmi_property_map[prop];
+ if (type != valid_type)
+ return -EINVAL;
+
+ switch (prop) {
+ case HP_WMI_PROPERTY_OPERATIONAL_STATUS:
+ /* Old variant: CurrentState follows OperationalStatus. */
+ if (!is_new)
+ prop = HP_WMI_PROPERTY_CURRENT_STATE - 1;
+ break;
+
+ case HP_WMI_PROPERTY_SIZE:
+ /* New variant: Size == count of PossibleStates[]. */
+ if (count != elements[i].integer.value)
+ return -EINVAL;
+ break;
+
+ case HP_WMI_PROPERTY_POSSIBLE_STATES:
+ /* PossibleStates[0] has already been type-checked. */
+ for (j = 0; i + 1 < elem_count && j + 1 < count; j++) {
+ type = elements[++i].type;
+ if (type != valid_type)
+ return -EINVAL;
+ }
+
+ /* Old variant: BaseUnits follows PossibleStates[]. */
+ if (!is_new)
+ prop = HP_WMI_PROPERTY_BASE_UNITS - 1;
+ break;
+
+ case HP_WMI_PROPERTY_CURRENT_STATE:
+ /* Old variant: PossibleStates[] follows CurrentState. */
+ if (!is_new)
+ prop = HP_WMI_PROPERTY_POSSIBLE_STATES - 1;
+ break;
+ }
+ }
+
+ if (prop != last_prop + 1)
+ return -EINVAL;
+
+ *out_size = count;
+ *out_is_new = is_new;
+
+ return 0;
+}
+
+static int
+numeric_sensor_is_connected(const struct hp_wmi_numeric_sensor *nsensor)
+{
+ u32 operational_status = nsensor->operational_status;
+
+ return operational_status != HP_WMI_STATUS_NO_CONTACT;
+}
+
+static int numeric_sensor_has_fault(const struct hp_wmi_numeric_sensor *nsensor)
+{
+ u32 operational_status = nsensor->operational_status;
+
+ switch (operational_status) {
+ case HP_WMI_STATUS_DEGRADED:
+ case HP_WMI_STATUS_STRESSED: /* e.g. Overload, overtemp. */
+ case HP_WMI_STATUS_PREDICTIVE_FAILURE: /* e.g. Fan removed. */
+ case HP_WMI_STATUS_ERROR:
+ case HP_WMI_STATUS_NON_RECOVERABLE_ERROR:
+ case HP_WMI_STATUS_NO_CONTACT:
+ case HP_WMI_STATUS_LOST_COMMUNICATION:
+ case HP_WMI_STATUS_ABORTED:
+ case HP_WMI_STATUS_SUPPORTING_ENTITY_IN_ERROR:
+
+ /* Assume combination by addition; bitwise OR doesn't make sense. */
+ case HP_WMI_STATUS_COMPLETED + HP_WMI_STATUS_DEGRADED:
+ case HP_WMI_STATUS_COMPLETED + HP_WMI_STATUS_ERROR:
+ return true;
+ }
+
+ return false;
+}
+
+/* scale_numeric_sensor - scale sensor reading for hwmon */
+static long scale_numeric_sensor(const struct hp_wmi_numeric_sensor *nsensor)
+{
+ u32 current_reading = nsensor->current_reading;
+ s32 unit_modifier = nsensor->unit_modifier;
+ u32 sensor_type = nsensor->sensor_type;
+ u32 base_units = nsensor->base_units;
+ s32 target_modifier;
+ long val;
+
+ /* Fan readings are in RPM units; others are in milliunits. */
+ target_modifier = sensor_type == HP_WMI_TYPE_AIR_FLOW ? 0 : -3;
+
+ val = current_reading;
+
+ for (; unit_modifier < target_modifier; unit_modifier++)
+ val = DIV_ROUND_CLOSEST(val, 10);
+
+ for (; unit_modifier > target_modifier; unit_modifier--) {
+ if (val > LONG_MAX / 10) {
+ val = LONG_MAX;
+ break;
+ }
+ val *= 10;
+ }
+
+ if (sensor_type == HP_WMI_TYPE_TEMPERATURE) {
+ switch (base_units) {
+ case HP_WMI_UNITS_DEGREES_F:
+ val -= MILLI * 32;
+ val = val <= LONG_MAX / 5 ?
+ DIV_ROUND_CLOSEST(val * 5, 9) :
+ DIV_ROUND_CLOSEST(val, 9) * 5;
+ break;
+
+ case HP_WMI_UNITS_DEGREES_K:
+ val = milli_kelvin_to_millicelsius(val);
+ break;
+ }
+ }
+
+ return val;
+}
+
+/*
+ * classify_numeric_sensor - classify a numeric sensor
+ * @nsensor: pointer to numeric sensor struct
+ *
+ * Returns an enum hp_wmi_type value on success,
+ * or a negative value if the sensor type is unsupported.
+ */
+static int classify_numeric_sensor(const struct hp_wmi_numeric_sensor *nsensor)
+{
+ u32 sensor_type = nsensor->sensor_type;
+ u32 base_units = nsensor->base_units;
+ const char *name = nsensor->name;
+
+ switch (sensor_type) {
+ case HP_WMI_TYPE_TEMPERATURE:
+ /*
+ * Some systems have sensors named "X Thermal Index" in "Other"
+ * units. Tested CPU sensor examples were found to be in °C,
+ * albeit perhaps "differently" accurate; e.g. readings were
+ * reliably -6°C vs. coretemp on a HP Compaq Elite 8300, and
+ * +8°C on an EliteOne G1 800. But this is still within the
+ * realm of plausibility for cheaply implemented motherboard
+ * sensors, and chassis readings were about as expected.
+ */
+ if ((base_units == HP_WMI_UNITS_OTHER &&
+ strstr(name, HP_WMI_PATTERN_TEMP_SENSOR)) ||
+ base_units == HP_WMI_UNITS_DEGREES_C ||
+ base_units == HP_WMI_UNITS_DEGREES_F ||
+ base_units == HP_WMI_UNITS_DEGREES_K)
+ return HP_WMI_TYPE_TEMPERATURE;
+ break;
+
+ case HP_WMI_TYPE_VOLTAGE:
+ if (base_units == HP_WMI_UNITS_VOLTS)
+ return HP_WMI_TYPE_VOLTAGE;
+ break;
+
+ case HP_WMI_TYPE_CURRENT:
+ if (base_units == HP_WMI_UNITS_AMPS)
+ return HP_WMI_TYPE_CURRENT;
+ break;
+
+ case HP_WMI_TYPE_AIR_FLOW:
+ /*
+ * Strangely, HP considers fan RPM sensor type to be
+ * "Air Flow" instead of the more intuitive "Tachometer".
+ */
+ if (base_units == HP_WMI_UNITS_RPM)
+ return HP_WMI_TYPE_AIR_FLOW;
+ break;
+ }
+
+ return -EINVAL;
+}
+
+static int
+populate_numeric_sensor_from_wobj(struct device *dev,
+ struct hp_wmi_numeric_sensor *nsensor,
+ union acpi_object *wobj, bool *out_is_new)
+{
+ int last_prop = HP_WMI_PROPERTY_RATE_UNITS;
+ int prop = HP_WMI_PROPERTY_NAME;
+ const char **possible_states;
+ union acpi_object *element;
+ acpi_object_type type;
+ char *string;
+ bool is_new;
+ u32 value;
+ u8 size;
+ int err;
+
+ err = check_numeric_sensor_wobj(wobj, &size, &is_new);
+ if (err)
+ return err;
+
+ possible_states = devm_kcalloc(dev, size, sizeof(*possible_states),
+ GFP_KERNEL);
+ if (!possible_states)
+ return -ENOMEM;
+
+ element = wobj->package.elements;
+ nsensor->possible_states = possible_states;
+ nsensor->size = size;
+
+ if (!is_new)
+ last_prop = HP_WMI_PROPERTY_CURRENT_READING;
+
+ for (; prop <= last_prop; prop++) {
+ type = hp_wmi_property_map[prop];
+
+ err = extract_acpi_value(dev, element, type, &value, &string);
+ if (err)
+ return err;
+
+ element++;
+
+ switch (prop) {
+ case HP_WMI_PROPERTY_NAME:
+ nsensor->name = string;
+ break;
+
+ case HP_WMI_PROPERTY_DESCRIPTION:
+ nsensor->description = string;
+ break;
+
+ case HP_WMI_PROPERTY_SENSOR_TYPE:
+ if (value > HP_WMI_TYPE_AIR_FLOW)
+ return -EINVAL;
+
+ nsensor->sensor_type = value;
+ break;
+
+ case HP_WMI_PROPERTY_OTHER_SENSOR_TYPE:
+ nsensor->other_sensor_type = string;
+ break;
+
+ case HP_WMI_PROPERTY_OPERATIONAL_STATUS:
+ nsensor->operational_status = value;
+
+ /* Old variant: CurrentState follows OperationalStatus. */
+ if (!is_new)
+ prop = HP_WMI_PROPERTY_CURRENT_STATE - 1;
+ break;
+
+ case HP_WMI_PROPERTY_SIZE:
+ break; /* Already set. */
+
+ case HP_WMI_PROPERTY_POSSIBLE_STATES:
+ *possible_states++ = string;
+ if (--size)
+ prop--;
+
+ /* Old variant: BaseUnits follows PossibleStates[]. */
+ if (!is_new && !size)
+ prop = HP_WMI_PROPERTY_BASE_UNITS - 1;
+ break;
+
+ case HP_WMI_PROPERTY_CURRENT_STATE:
+ nsensor->current_state = string;
+
+ /* Old variant: PossibleStates[] follows CurrentState. */
+ if (!is_new)
+ prop = HP_WMI_PROPERTY_POSSIBLE_STATES - 1;
+ break;
+
+ case HP_WMI_PROPERTY_BASE_UNITS:
+ nsensor->base_units = value;
+ break;
+
+ case HP_WMI_PROPERTY_UNIT_MODIFIER:
+ /* UnitModifier is signed. */
+ nsensor->unit_modifier = (s32)value;
+ break;
+
+ case HP_WMI_PROPERTY_CURRENT_READING:
+ nsensor->current_reading = value;
+ break;
+
+ case HP_WMI_PROPERTY_RATE_UNITS:
+ nsensor->rate_units = value;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ *out_is_new = is_new;
+
+ return 0;
+}
+
+/* update_numeric_sensor_from_wobj - update fungible sensor properties */
+static void
+update_numeric_sensor_from_wobj(struct device *dev,
+ struct hp_wmi_numeric_sensor *nsensor,
+ const union acpi_object *wobj)
+{
+ const union acpi_object *elements;
+ const union acpi_object *element;
+ const char *string;
+ bool is_new;
+ int offset;
+ u8 size;
+ int err;
+
+ err = check_numeric_sensor_wobj(wobj, &size, &is_new);
+ if (err)
+ return;
+
+ elements = wobj->package.elements;
+
+ element = &elements[HP_WMI_PROPERTY_OPERATIONAL_STATUS];
+ nsensor->operational_status = element->integer.value;
+
+ /*
+ * In general, an index offset is needed after PossibleStates[0].
+ * On a new variant, CurrentState is after PossibleStates[]. This is
+ * not the case on an old variant, but we still need to offset the
+ * read because CurrentState is where Size would be on a new variant.
+ */
+ offset = is_new ? size - 1 : -2;
+
+ element = &elements[HP_WMI_PROPERTY_CURRENT_STATE + offset];
+ string = strim(element->string.pointer);
+
+ if (strcmp(string, nsensor->current_state)) {
+ devm_kfree(dev, nsensor->current_state);
+ nsensor->current_state = hp_wmi_strdup(dev, string);
+ }
+
+ /* Old variant: -2 (not -1) because it lacks the Size property. */
+ if (!is_new)
+ offset = (int)size - 2; /* size is > 0, i.e. may be 1. */
+
+ element = &elements[HP_WMI_PROPERTY_UNIT_MODIFIER + offset];
+ nsensor->unit_modifier = (s32)element->integer.value;
+
+ element = &elements[HP_WMI_PROPERTY_CURRENT_READING + offset];
+ nsensor->current_reading = element->integer.value;
+}
+
+/*
+ * check_platform_events_wobj - validate a HPBIOS_PlatformEvents instance
+ * @wobj: pointer to WMI object instance to check
+ *
+ * Returns 0 on success, or a negative error code on error.
+ */
+static int check_platform_events_wobj(const union acpi_object *wobj)
+{
+ return check_wobj(wobj, hp_wmi_platform_events_property_map,
+ HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_STATUS);
+}
+
+static int
+populate_platform_events_from_wobj(struct device *dev,
+ struct hp_wmi_platform_events *pevents,
+ union acpi_object *wobj)
+{
+ int last_prop = HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_STATUS;
+ int prop = HP_WMI_PLATFORM_EVENTS_PROPERTY_NAME;
+ union acpi_object *element;
+ acpi_object_type type;
+ char *string;
+ u32 value;
+ int err;
+
+ err = check_platform_events_wobj(wobj);
+ if (err)
+ return err;
+
+ element = wobj->package.elements;
+
+ for (; prop <= last_prop; prop++, element++) {
+ type = hp_wmi_platform_events_property_map[prop];
+
+ err = extract_acpi_value(dev, element, type, &value, &string);
+ if (err)
+ return err;
+
+ switch (prop) {
+ case HP_WMI_PLATFORM_EVENTS_PROPERTY_NAME:
+ pevents->name = string;
+ break;
+
+ case HP_WMI_PLATFORM_EVENTS_PROPERTY_DESCRIPTION:
+ pevents->description = string;
+ break;
+
+ case HP_WMI_PLATFORM_EVENTS_PROPERTY_SOURCE_NAMESPACE:
+ if (strcasecmp(HP_WMI_EVENT_NAMESPACE, string))
+ return -EINVAL;
+
+ pevents->source_namespace = string;
+ break;
+
+ case HP_WMI_PLATFORM_EVENTS_PROPERTY_SOURCE_CLASS:
+ if (strcasecmp(HP_WMI_EVENT_CLASS, string))
+ return -EINVAL;
+
+ pevents->source_class = string;
+ break;
+
+ case HP_WMI_PLATFORM_EVENTS_PROPERTY_CATEGORY:
+ pevents->category = value;
+ break;
+
+ case HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_SEVERITY:
+ pevents->possible_severity = value;
+ break;
+
+ case HP_WMI_PLATFORM_EVENTS_PROPERTY_POSSIBLE_STATUS:
+ pevents->possible_status = value;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * check_event_wobj - validate a HPBIOS_BIOSEvent instance
+ * @wobj: pointer to WMI object instance to check
+ *
+ * Returns 0 on success, or a negative error code on error.
+ */
+static int check_event_wobj(const union acpi_object *wobj)
+{
+ return check_wobj(wobj, hp_wmi_event_property_map,
+ HP_WMI_EVENT_PROPERTY_STATUS);
+}
+
+static int populate_event_from_wobj(struct hp_wmi_event *event,
+ union acpi_object *wobj)
+{
+ int prop = HP_WMI_EVENT_PROPERTY_NAME;
+ union acpi_object *element;
+ int err;
+
+ err = check_event_wobj(wobj);
+ if (err)
+ return err;
+
+ element = wobj->package.elements;
+
+ /* Extracted strings are NOT device-managed copies. */
+
+ for (; prop <= HP_WMI_EVENT_PROPERTY_CATEGORY; prop++, element++) {
+ switch (prop) {
+ case HP_WMI_EVENT_PROPERTY_NAME:
+ event->name = strim(element->string.pointer);
+ break;
+
+ case HP_WMI_EVENT_PROPERTY_DESCRIPTION:
+ event->description = strim(element->string.pointer);
+ break;
+
+ case HP_WMI_EVENT_PROPERTY_CATEGORY:
+ event->category = element->integer.value;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * classify_event - classify an event
+ * @name: event name
+ * @category: event category
+ *
+ * Classify instances of both HPBIOS_PlatformEvents and HPBIOS_BIOSEvent from
+ * property values. Recognition criteria are based on multiple ACPI dumps [3].
+ *
+ * Returns an enum hp_wmi_type value on success,
+ * or a negative value if the event type is unsupported.
+ */
+static int classify_event(const char *event_name, u32 category)
+{
+ if (category != HP_WMI_CATEGORY_SENSOR)
+ return -EINVAL;
+
+ /* Fan events have Name "X Stall". */
+ if (strstr(event_name, HP_WMI_PATTERN_FAN_ALARM))
+ return HP_WMI_TYPE_AIR_FLOW;
+
+ /* Intrusion events have Name "Hood Intrusion". */
+ if (!strcmp(event_name, HP_WMI_PATTERN_INTRUSION_ALARM))
+ return HP_WMI_TYPE_INTRUSION;
+
+ /*
+ * Temperature events have Name either "Thermal Caution" or
+ * "Thermal Critical". Deal only with "Thermal Critical" events.
+ *
+ * "Thermal Caution" events have Status "Stressed", informing us that
+ * the OperationalStatus of the related sensor has become "Stressed".
+ * However, this is already a fault condition that will clear itself
+ * when the sensor recovers, so we have no further interest in them.
+ */
+ if (!strcmp(event_name, HP_WMI_PATTERN_TEMP_ALARM))
+ return HP_WMI_TYPE_TEMPERATURE;
+
+ return -EINVAL;
+}
+
+/*
+ * interpret_info - interpret sensor for hwmon
+ * @info: pointer to sensor info struct
+ *
+ * Should be called after the numeric sensor member has been updated.
+ */
+static void interpret_info(struct hp_wmi_info *info)
+{
+ const struct hp_wmi_numeric_sensor *nsensor = &info->nsensor;
+
+ info->cached_val = scale_numeric_sensor(nsensor);
+ info->last_updated = jiffies;
+}
+
+/*
+ * hp_wmi_update_info - poll WMI to update sensor info
+ * @state: pointer to driver state
+ * @info: pointer to sensor info struct
+ *
+ * Returns 0 on success, or a negative error code on error.
+ */
+static int hp_wmi_update_info(struct hp_wmi_sensors *state,
+ struct hp_wmi_info *info)
+{
+ struct hp_wmi_numeric_sensor *nsensor = &info->nsensor;
+ struct device *dev = &state->wdev->dev;
+ const union acpi_object *wobj;
+ u8 instance = info->instance;
+ int ret = 0;
+
+ if (time_after(jiffies, info->last_updated + HZ)) {
+ mutex_lock(&state->lock);
+
+ wobj = hp_wmi_get_wobj(HP_WMI_NUMERIC_SENSOR_GUID, instance);
+ if (!wobj) {
+ ret = -EIO;
+ goto out_unlock;
+ }
+
+ update_numeric_sensor_from_wobj(dev, nsensor, wobj);
+
+ interpret_info(info);
+
+ kfree(wobj);
+
+out_unlock:
+ mutex_unlock(&state->lock);
+ }
+
+ return ret;
+}
+
+#if CONFIG_DEBUG_FS
+
+static int basic_string_show(struct seq_file *seqf, void *ignored)
+{
+ const char *str = seqf->private;
+
+ seq_printf(seqf, "%s\n", str);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(basic_string);
+
+static int fungible_show(struct seq_file *seqf, enum hp_wmi_property prop)
+{
+ struct hp_wmi_numeric_sensor *nsensor;
+ struct hp_wmi_sensors *state;
+ struct hp_wmi_info *info;
+ int err;
+
+ info = seqf->private;
+ state = info->state;
+ nsensor = &info->nsensor;
+
+ err = hp_wmi_update_info(state, info);
+ if (err)
+ return err;
+
+ switch (prop) {
+ case HP_WMI_PROPERTY_OPERATIONAL_STATUS:
+ seq_printf(seqf, "%u\n", nsensor->operational_status);
+ break;
+
+ case HP_WMI_PROPERTY_CURRENT_STATE:
+ seq_printf(seqf, "%s\n", nsensor->current_state);
+ break;
+
+ case HP_WMI_PROPERTY_UNIT_MODIFIER:
+ seq_printf(seqf, "%d\n", nsensor->unit_modifier);
+ break;
+
+ case HP_WMI_PROPERTY_CURRENT_READING:
+ seq_printf(seqf, "%u\n", nsensor->current_reading);
+ break;
+
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int operational_status_show(struct seq_file *seqf, void *ignored)
+{
+ return fungible_show(seqf, HP_WMI_PROPERTY_OPERATIONAL_STATUS);
+}
+DEFINE_SHOW_ATTRIBUTE(operational_status);
+
+static int current_state_show(struct seq_file *seqf, void *ignored)
+{
+ return fungible_show(seqf, HP_WMI_PROPERTY_CURRENT_STATE);
+}
+DEFINE_SHOW_ATTRIBUTE(current_state);
+
+static int possible_states_show(struct seq_file *seqf, void *ignored)
+{
+ struct hp_wmi_numeric_sensor *nsensor = seqf->private;
+ u8 i;
+
+ for (i = 0; i < nsensor->size; i++)
+ seq_printf(seqf, "%s%s", i ? "," : "",
+ nsensor->possible_states[i]);
+
+ seq_puts(seqf, "\n");
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(possible_states);
+
+static int unit_modifier_show(struct seq_file *seqf, void *ignored)
+{
+ return fungible_show(seqf, HP_WMI_PROPERTY_UNIT_MODIFIER);
+}
+DEFINE_SHOW_ATTRIBUTE(unit_modifier);
+
+static int current_reading_show(struct seq_file *seqf, void *ignored)
+{
+ return fungible_show(seqf, HP_WMI_PROPERTY_CURRENT_READING);
+}
+DEFINE_SHOW_ATTRIBUTE(current_reading);
+
+/* hp_wmi_devm_debugfs_remove - devm callback for debugfs cleanup */
+static void hp_wmi_devm_debugfs_remove(void *res)
+{
+ debugfs_remove_recursive(res);
+}
+
+/* hp_wmi_debugfs_init - create and populate debugfs directory tree */
+static void hp_wmi_debugfs_init(struct device *dev, struct hp_wmi_info *info,
+ struct hp_wmi_platform_events *pevents,
+ u8 icount, u8 pcount, bool is_new)
+{
+ struct hp_wmi_numeric_sensor *nsensor;
+ char buf[HP_WMI_MAX_STR_SIZE];
+ struct dentry *debugfs;
+ struct dentry *entries;
+ struct dentry *dir;
+ int err;
+ u8 i;
+
+ /* dev_name() gives a not-very-friendly GUID for WMI devices. */
+ scnprintf(buf, sizeof(buf), "hp-wmi-sensors-%u", dev->id);
+
+ debugfs = debugfs_create_dir(buf, NULL);
+ if (IS_ERR(debugfs))
+ return;
+
+ err = devm_add_action_or_reset(dev, hp_wmi_devm_debugfs_remove,
+ debugfs);
+ if (err)
+ return;
+
+ entries = debugfs_create_dir("sensor", debugfs);
+
+ for (i = 0; i < icount; i++, info++) {
+ nsensor = &info->nsensor;
+
+ scnprintf(buf, sizeof(buf), "%u", i);
+ dir = debugfs_create_dir(buf, entries);
+
+ debugfs_create_file("name", 0444, dir,
+ (void *)nsensor->name,
+ &basic_string_fops);
+
+ debugfs_create_file("description", 0444, dir,
+ (void *)nsensor->description,
+ &basic_string_fops);
+
+ debugfs_create_u32("sensor_type", 0444, dir,
+ &nsensor->sensor_type);
+
+ debugfs_create_file("other_sensor_type", 0444, dir,
+ (void *)nsensor->other_sensor_type,
+ &basic_string_fops);
+
+ debugfs_create_file("operational_status", 0444, dir,
+ info, &operational_status_fops);
+
+ debugfs_create_file("possible_states", 0444, dir,
+ nsensor, &possible_states_fops);
+
+ debugfs_create_file("current_state", 0444, dir,
+ info, &current_state_fops);
+
+ debugfs_create_u32("base_units", 0444, dir,
+ &nsensor->base_units);
+
+ debugfs_create_file("unit_modifier", 0444, dir,
+ info, &unit_modifier_fops);
+
+ debugfs_create_file("current_reading", 0444, dir,
+ info, &current_reading_fops);
+
+ if (is_new)
+ debugfs_create_u32("rate_units", 0444, dir,
+ &nsensor->rate_units);
+ }
+
+ if (!pcount)
+ return;
+
+ entries = debugfs_create_dir("platform_events", debugfs);
+
+ for (i = 0; i < pcount; i++, pevents++) {
+ scnprintf(buf, sizeof(buf), "%u", i);
+ dir = debugfs_create_dir(buf, entries);
+
+ debugfs_create_file("name", 0444, dir,
+ (void *)pevents->name,
+ &basic_string_fops);
+
+ debugfs_create_file("description", 0444, dir,
+ (void *)pevents->description,
+ &basic_string_fops);
+
+ debugfs_create_file("source_namespace", 0444, dir,
+ (void *)pevents->source_namespace,
+ &basic_string_fops);
+
+ debugfs_create_file("source_class", 0444, dir,
+ (void *)pevents->source_class,
+ &basic_string_fops);
+
+ debugfs_create_u32("category", 0444, dir,
+ &pevents->category);
+
+ debugfs_create_u32("possible_severity", 0444, dir,
+ &pevents->possible_severity);
+
+ debugfs_create_u32("possible_status", 0444, dir,
+ &pevents->possible_status);
+ }
+}
+
+#else
+
+static void hp_wmi_debugfs_init(struct device *dev, struct hp_wmi_info *info,
+ struct hp_wmi_platform_events *pevents,
+ u8 icount, u8 pcount, bool is_new)
+{
+}
+
+#endif
+
+static umode_t hp_wmi_hwmon_is_visible(const void *drvdata,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ const struct hp_wmi_sensors *state = drvdata;
+ const struct hp_wmi_info *info;
+
+ if (type == hwmon_intrusion)
+ return state->has_intrusion ? 0644 : 0;
+
+ if (!state->info_map[type] || !state->info_map[type][channel])
+ return 0;
+
+ info = state->info_map[type][channel];
+
+ if ((type == hwmon_temp && attr == hwmon_temp_alarm) ||
+ (type == hwmon_fan && attr == hwmon_fan_alarm))
+ return info->has_alarm ? 0444 : 0;
+
+ return 0444;
+}
+
+static int hp_wmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *out_val)
+{
+ struct hp_wmi_sensors *state = dev_get_drvdata(dev);
+ const struct hp_wmi_numeric_sensor *nsensor;
+ struct hp_wmi_info *info;
+ int err;
+
+ if (type == hwmon_intrusion) {
+ *out_val = state->intrusion ? 1 : 0;
+
+ return 0;
+ }
+
+ info = state->info_map[type][channel];
+
+ if ((type == hwmon_temp && attr == hwmon_temp_alarm) ||
+ (type == hwmon_fan && attr == hwmon_fan_alarm)) {
+ *out_val = info->alarm ? 1 : 0;
+ info->alarm = false;
+
+ return 0;
+ }
+
+ nsensor = &info->nsensor;
+
+ err = hp_wmi_update_info(state, info);
+ if (err)
+ return err;
+
+ if ((type == hwmon_temp && attr == hwmon_temp_fault) ||
+ (type == hwmon_fan && attr == hwmon_fan_fault))
+ *out_val = numeric_sensor_has_fault(nsensor);
+ else
+ *out_val = info->cached_val;
+
+ return 0;
+}
+
+static int hp_wmi_hwmon_read_string(struct device *dev,
+ enum hwmon_sensor_types type, u32 attr,
+ int channel, const char **out_str)
+{
+ const struct hp_wmi_sensors *state = dev_get_drvdata(dev);
+ const struct hp_wmi_info *info;
+
+ info = state->info_map[type][channel];
+ *out_str = info->nsensor.name;
+
+ return 0;
+}
+
+static int hp_wmi_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+{
+ struct hp_wmi_sensors *state = dev_get_drvdata(dev);
+
+ if (val)
+ return -EINVAL;
+
+ mutex_lock(&state->lock);
+
+ state->intrusion = false;
+
+ mutex_unlock(&state->lock);
+
+ return 0;
+}
+
+static const struct hwmon_ops hp_wmi_hwmon_ops = {
+ .is_visible = hp_wmi_hwmon_is_visible,
+ .read = hp_wmi_hwmon_read,
+ .read_string = hp_wmi_hwmon_read_string,
+ .write = hp_wmi_hwmon_write,
+};
+
+static struct hwmon_chip_info hp_wmi_chip_info = {
+ .ops = &hp_wmi_hwmon_ops,
+ .info = NULL,
+};
+
+static struct hp_wmi_info *match_fan_event(struct hp_wmi_sensors *state,
+ const char *event_description)
+{
+ struct hp_wmi_info **ptr_info = state->info_map[hwmon_fan];
+ u8 fan_count = state->channel_count[hwmon_fan];
+ struct hp_wmi_info *info;
+ const char *name;
+ u8 i;
+
+ /* Fan event has Description "X Speed". Sensor has Name "X[ Speed]". */
+
+ for (i = 0; i < fan_count; i++, ptr_info++) {
+ info = *ptr_info;
+ name = info->nsensor.name;
+
+ if (strstr(event_description, name))
+ return info;
+ }
+
+ return NULL;
+}
+
+static u8 match_temp_events(struct hp_wmi_sensors *state,
+ const char *event_description,
+ struct hp_wmi_info *temp_info[])
+{
+ struct hp_wmi_info **ptr_info = state->info_map[hwmon_temp];
+ u8 temp_count = state->channel_count[hwmon_temp];
+ struct hp_wmi_info *info;
+ const char *name;
+ u8 count = 0;
+ bool is_cpu;
+ bool is_sys;
+ u8 i;
+
+ /* Description is either "CPU Thermal Index" or "Chassis Thermal Index". */
+
+ is_cpu = !strcmp(event_description, HP_WMI_PATTERN_CPU_TEMP);
+ is_sys = !strcmp(event_description, HP_WMI_PATTERN_SYS_TEMP);
+ if (!is_cpu && !is_sys)
+ return 0;
+
+ /*
+ * CPU event: Match one sensor with Name either "CPU Thermal Index" or
+ * "CPU Temperature", or multiple with Name(s) "CPU[#] Temperature".
+ *
+ * Chassis event: Match one sensor with Name either
+ * "Chassis Thermal Index" or "System Ambient Temperature".
+ */
+
+ for (i = 0; i < temp_count; i++, ptr_info++) {
+ info = *ptr_info;
+ name = info->nsensor.name;
+
+ if ((is_cpu && (!strcmp(name, HP_WMI_PATTERN_CPU_TEMP) ||
+ !strcmp(name, HP_WMI_PATTERN_CPU_TEMP2))) ||
+ (is_sys && (!strcmp(name, HP_WMI_PATTERN_SYS_TEMP) ||
+ !strcmp(name, HP_WMI_PATTERN_SYS_TEMP2)))) {
+ temp_info[0] = info;
+ return 1;
+ }
+
+ if (is_cpu && (strstr(name, HP_WMI_PATTERN_CPU) &&
+ strstr(name, HP_WMI_PATTERN_TEMP)))
+ temp_info[count++] = info;
+ }
+
+ return count;
+}
+
+/* hp_wmi_devm_debugfs_remove - devm callback for WMI event handler removal */
+static void hp_wmi_devm_notify_remove(void *ignored)
+{
+ wmi_remove_notify_handler(HP_WMI_EVENT_GUID);
+}
+
+/* hp_wmi_notify - WMI event notification handler */
+static void hp_wmi_notify(u32 value, void *context)
+{
+ struct hp_wmi_info *temp_info[HP_WMI_MAX_INSTANCES] = {};
+ struct acpi_buffer out = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct hp_wmi_sensors *state = context;
+ struct device *dev = &state->wdev->dev;
+ struct hp_wmi_info *fan_info;
+ struct hp_wmi_event event;
+ union acpi_object *wobj;
+ acpi_status err;
+ int event_type;
+ u8 count;
+
+ /*
+ * The following warning may occur in the kernel log:
+ *
+ * ACPI Warning: \_SB.WMID._WED: Return type mismatch -
+ * found Package, expected Integer/String/Buffer
+ *
+ * After using [4] to decode BMOF blobs found in [3], careless copying
+ * of BIOS code seems the most likely explanation for this warning.
+ * HP_WMI_EVENT_GUID refers to \\.\root\WMI\HPBIOS_BIOSEvent on
+ * business-class systems, but it refers to \\.\root\WMI\hpqBEvnt on
+ * non-business-class systems. Per the existing hp-wmi driver, it
+ * looks like an instance of hpqBEvnt delivered as event data may
+ * indeed take the form of a raw ACPI_BUFFER on non-business-class
+ * systems ("may" because ASL shows some BIOSes do strange things).
+ *
+ * In any case, we can ignore this warning, because we always validate
+ * the event data to ensure it is an ACPI_PACKAGE containing a
+ * HPBIOS_BIOSEvent instance.
+ */
+
+ mutex_lock(&state->lock);
+
+ err = wmi_get_event_data(value, &out);
+ if (ACPI_FAILURE(err))
+ goto out_unlock;
+
+ wobj = out.pointer;
+
+ err = populate_event_from_wobj(&event, wobj);
+ if (err) {
+ dev_warn(dev, "Bad event data (ACPI type %d)\n", wobj->type);
+ goto out_free_wobj;
+ }
+
+ event_type = classify_event(event.name, event.category);
+ switch (event_type) {
+ case HP_WMI_TYPE_AIR_FLOW:
+ fan_info = match_fan_event(state, event.description);
+ if (fan_info)
+ fan_info->alarm = true;
+ break;
+
+ case HP_WMI_TYPE_INTRUSION:
+ state->intrusion = true;
+ break;
+
+ case HP_WMI_TYPE_TEMPERATURE:
+ count = match_temp_events(state, event.description, temp_info);
+ while (count)
+ temp_info[--count]->alarm = true;
+ break;
+
+ default:
+ break;
+ }
+
+out_free_wobj:
+ kfree(wobj);
+
+out_unlock:
+ mutex_unlock(&state->lock);
+}
+
+static int init_platform_events(struct device *dev,
+ struct hp_wmi_platform_events **out_pevents,
+ u8 *out_pcount)
+{
+ struct hp_wmi_platform_events *pevents_arr;
+ struct hp_wmi_platform_events *pevents;
+ union acpi_object *wobj;
+ u8 count;
+ int err;
+ u8 i;
+
+ count = hp_wmi_wobj_instance_count(HP_WMI_PLATFORM_EVENTS_GUID);
+ if (!count) {
+ *out_pcount = 0;
+
+ dev_dbg(dev, "No platform events\n");
+
+ return 0;
+ }
+
+ pevents_arr = devm_kcalloc(dev, count, sizeof(*pevents), GFP_KERNEL);
+ if (!pevents_arr)
+ return -ENOMEM;
+
+ for (i = 0, pevents = pevents_arr; i < count; i++, pevents++) {
+ wobj = hp_wmi_get_wobj(HP_WMI_PLATFORM_EVENTS_GUID, i);
+ if (!wobj)
+ return -EIO;
+
+ err = populate_platform_events_from_wobj(dev, pevents, wobj);
+
+ kfree(wobj);
+
+ if (err)
+ return err;
+ }
+
+ *out_pevents = pevents_arr;
+ *out_pcount = count;
+
+ dev_dbg(dev, "Found %u platform events\n", count);
+
+ return 0;
+}
+
+static int init_numeric_sensors(struct hp_wmi_sensors *state,
+ struct hp_wmi_info *connected[],
+ struct hp_wmi_info **out_info,
+ u8 *out_icount, u8 *out_count,
+ bool *out_is_new)
+{
+ struct hp_wmi_info ***info_map = state->info_map;
+ u8 *channel_count = state->channel_count;
+ struct device *dev = &state->wdev->dev;
+ struct hp_wmi_numeric_sensor *nsensor;
+ u8 channel_index[hwmon_max] = {};
+ enum hwmon_sensor_types type;
+ struct hp_wmi_info *info_arr;
+ struct hp_wmi_info *info;
+ union acpi_object *wobj;
+ u8 count = 0;
+ bool is_new;
+ u8 icount;
+ int wtype;
+ int err;
+ u8 c;
+ u8 i;
+
+ icount = hp_wmi_wobj_instance_count(HP_WMI_NUMERIC_SENSOR_GUID);
+ if (!icount)
+ return -ENODATA;
+
+ info_arr = devm_kcalloc(dev, icount, sizeof(*info), GFP_KERNEL);
+ if (!info_arr)
+ return -ENOMEM;
+
+ for (i = 0, info = info_arr; i < icount; i++, info++) {
+ wobj = hp_wmi_get_wobj(HP_WMI_NUMERIC_SENSOR_GUID, i);
+ if (!wobj)
+ return -EIO;
+
+ info->instance = i;
+ info->state = state;
+ nsensor = &info->nsensor;
+
+ err = populate_numeric_sensor_from_wobj(dev, nsensor, wobj,
+ &is_new);
+
+ kfree(wobj);
+
+ if (err)
+ return err;
+
+ if (!numeric_sensor_is_connected(nsensor))
+ continue;
+
+ wtype = classify_numeric_sensor(nsensor);
+ if (wtype < 0)
+ continue;
+
+ type = hp_wmi_hwmon_type_map[wtype];
+
+ channel_count[type]++;
+
+ info->type = type;
+
+ interpret_info(info);
+
+ connected[count++] = info;
+ }
+
+ dev_dbg(dev, "Found %u sensors (%u connected)\n", i, count);
+
+ for (i = 0; i < count; i++) {
+ info = connected[i];
+ type = info->type;
+ c = channel_index[type]++;
+
+ if (!info_map[type]) {
+ info_map[type] = devm_kcalloc(dev, channel_count[type],
+ sizeof(*info_map),
+ GFP_KERNEL);
+ if (!info_map[type])
+ return -ENOMEM;
+ }
+
+ info_map[type][c] = info;
+ }
+
+ *out_info = info_arr;
+ *out_icount = icount;
+ *out_count = count;
+ *out_is_new = is_new;
+
+ return 0;
+}
+
+static bool find_event_attributes(struct hp_wmi_sensors *state,
+ struct hp_wmi_platform_events *pevents,
+ u8 pevents_count)
+{
+ /*
+ * The existence of this HPBIOS_PlatformEvents instance:
+ *
+ * {
+ * Name = "Rear Chassis Fan0 Stall";
+ * Description = "Rear Chassis Fan0 Speed";
+ * Category = 3; // "Sensor"
+ * PossibleSeverity = 25; // "Critical Failure"
+ * PossibleStatus = 5; // "Predictive Failure"
+ * [...]
+ * }
+ *
+ * means that this HPBIOS_BIOSEvent instance may occur:
+ *
+ * {
+ * Name = "Rear Chassis Fan0 Stall";
+ * Description = "Rear Chassis Fan0 Speed";
+ * Category = 3; // "Sensor"
+ * Severity = 25; // "Critical Failure"
+ * Status = 5; // "Predictive Failure"
+ * }
+ *
+ * After the event occurs (e.g. because the fan was unplugged),
+ * polling the related HPBIOS_BIOSNumericSensor instance gives:
+ *
+ * {
+ * Name = "Rear Chassis Fan0";
+ * Description = "Reports rear chassis fan0 speed";
+ * OperationalStatus = 5; // "Predictive Failure", was 3 ("OK")
+ * CurrentReading = 0;
+ * [...]
+ * }
+ *
+ * In this example, the hwmon fan channel for "Rear Chassis Fan0"
+ * should support the alarm flag and have it be set if the related
+ * HPBIOS_BIOSEvent instance occurs.
+ *
+ * In addition to fan events, temperature (CPU/chassis) and intrusion
+ * events are relevant to hwmon [2]. Note that much information in [2]
+ * is unreliable; it is referenced in addition to ACPI dumps [3] merely
+ * to support the conclusion that sensor and event names/descriptions
+ * are systematic enough to allow this driver to match them.
+ *
+ * Complications and limitations:
+ *
+ * - Strings are freeform and may vary, cf. sensor Name "CPU0 Fan"
+ * on a Z420 vs. "CPU Fan Speed" on an EliteOne 800 G1.
+ * - Leading/trailing whitespace is a rare but real possibility [3].
+ * - The HPBIOS_PlatformEvents object may not exist or its instances
+ * may show that the system only has e.g. BIOS setting-related
+ * events (cf. the ProBook 4540s and ProBook 470 G0 [3]).
+ */
+
+ struct hp_wmi_info *temp_info[HP_WMI_MAX_INSTANCES] = {};
+ const char *event_description;
+ struct hp_wmi_info *fan_info;
+ bool has_events = false;
+ const char *event_name;
+ u32 event_category;
+ int event_type;
+ u8 count;
+ u8 i;
+
+ for (i = 0; i < pevents_count; i++, pevents++) {
+ event_name = pevents->name;
+ event_description = pevents->description;
+ event_category = pevents->category;
+
+ event_type = classify_event(event_name, event_category);
+ switch (event_type) {
+ case HP_WMI_TYPE_AIR_FLOW:
+ fan_info = match_fan_event(state, event_description);
+ if (!fan_info)
+ break;
+
+ fan_info->has_alarm = true;
+ has_events = true;
+ break;
+
+ case HP_WMI_TYPE_INTRUSION:
+ state->has_intrusion = true;
+ has_events = true;
+ break;
+
+ case HP_WMI_TYPE_TEMPERATURE:
+ count = match_temp_events(state, event_description,
+ temp_info);
+ if (!count)
+ break;
+
+ while (count)
+ temp_info[--count]->has_alarm = true;
+ has_events = true;
+ break;
+
+ default:
+ break;
+ }
+ }
+
+ return has_events;
+}
+
+static int make_chip_info(struct hp_wmi_sensors *state, bool has_events)
+{
+ const struct hwmon_channel_info **ptr_channel_info;
+ struct hp_wmi_info ***info_map = state->info_map;
+ u8 *channel_count = state->channel_count;
+ struct hwmon_channel_info *channel_info;
+ struct device *dev = &state->wdev->dev;
+ enum hwmon_sensor_types type;
+ u8 type_count = 0;
+ u32 *config;
+ u32 attr;
+ u8 count;
+ u8 i;
+
+ if (channel_count[hwmon_temp])
+ channel_count[hwmon_chip] = 1;
+
+ if (has_events && state->has_intrusion)
+ channel_count[hwmon_intrusion] = 1;
+
+ for (type = hwmon_chip; type < hwmon_max; type++)
+ if (channel_count[type])
+ type_count++;
+
+ channel_info = devm_kcalloc(dev, type_count,
+ sizeof(*channel_info), GFP_KERNEL);
+ if (!channel_info)
+ return -ENOMEM;
+
+ ptr_channel_info = devm_kcalloc(dev, type_count + 1,
+ sizeof(*ptr_channel_info), GFP_KERNEL);
+ if (!ptr_channel_info)
+ return -ENOMEM;
+
+ hp_wmi_chip_info.info = ptr_channel_info;
+
+ for (type = hwmon_chip; type < hwmon_max; type++) {
+ count = channel_count[type];
+ if (!count)
+ continue;
+
+ config = devm_kcalloc(dev, count + 1,
+ sizeof(*config), GFP_KERNEL);
+ if (!config)
+ return -ENOMEM;
+
+ attr = hp_wmi_hwmon_attributes[type];
+ channel_info->type = type;
+ channel_info->config = config;
+ memset32(config, attr, count);
+
+ *ptr_channel_info++ = channel_info++;
+
+ if (!has_events || (type != hwmon_temp && type != hwmon_fan))
+ continue;
+
+ attr = type == hwmon_temp ? HWMON_T_ALARM : HWMON_F_ALARM;
+
+ for (i = 0; i < count; i++)
+ if (info_map[type][i]->has_alarm)
+ config[i] |= attr;
+ }
+
+ return 0;
+}
+
+static bool add_event_handler(struct hp_wmi_sensors *state)
+{
+ struct device *dev = &state->wdev->dev;
+ int err;
+
+ err = wmi_install_notify_handler(HP_WMI_EVENT_GUID,
+ hp_wmi_notify, state);
+ if (err) {
+ dev_info(dev, "Failed to subscribe to WMI event\n");
+ return false;
+ }
+
+ err = devm_add_action_or_reset(dev, hp_wmi_devm_notify_remove, NULL);
+ if (err)
+ return false;
+
+ return true;
+}
+
+static int hp_wmi_sensors_init(struct hp_wmi_sensors *state)
+{
+ struct hp_wmi_info *connected[HP_WMI_MAX_INSTANCES];
+ struct hp_wmi_platform_events *pevents;
+ struct device *dev = &state->wdev->dev;
+ struct hp_wmi_info *info;
+ struct device *hwdev;
+ bool has_events;
+ bool is_new;
+ u8 icount;
+ u8 pcount;
+ u8 count;
+ int err;
+
+ err = init_platform_events(dev, &pevents, &pcount);
+ if (err)
+ return err;
+
+ err = init_numeric_sensors(state, connected, &info,
+ &icount, &count, &is_new);
+ if (err)
+ return err;
+
+ hp_wmi_debugfs_init(dev, info, pevents, icount, pcount, is_new);
+
+ if (!count)
+ return 0; /* No connected sensors; debugfs only. */
+
+ has_events = find_event_attributes(state, pevents, pcount);
+
+ /* Survive failure to install WMI event handler. */
+ if (has_events && !add_event_handler(state))
+ has_events = false;
+
+ err = make_chip_info(state, has_events);
+ if (err)
+ return err;
+
+ hwdev = devm_hwmon_device_register_with_info(dev, "hp_wmi_sensors",
+ state, &hp_wmi_chip_info,
+ NULL);
+ return PTR_ERR_OR_ZERO(hwdev);
+}
+
+static int hp_wmi_sensors_probe(struct wmi_device *wdev, const void *context)
+{
+ struct device *dev = &wdev->dev;
+ struct hp_wmi_sensors *state;
+
+ state = devm_kzalloc(dev, sizeof(*state), GFP_KERNEL);
+ if (!state)
+ return -ENOMEM;
+
+ state->wdev = wdev;
+
+ mutex_init(&state->lock);
+
+ dev_set_drvdata(dev, state);
+
+ return hp_wmi_sensors_init(state);
+}
+
+static const struct wmi_device_id hp_wmi_sensors_id_table[] = {
+ { HP_WMI_NUMERIC_SENSOR_GUID, NULL },
+ {},
+};
+
+static struct wmi_driver hp_wmi_sensors_driver = {
+ .driver = { .name = "hp-wmi-sensors" },
+ .id_table = hp_wmi_sensors_id_table,
+ .probe = hp_wmi_sensors_probe,
+};
+module_wmi_driver(hp_wmi_sensors_driver);
+
+MODULE_AUTHOR("James Seo <james@equiv.tech>");
+MODULE_DESCRIPTION("HP WMI Sensors driver");
+MODULE_LICENSE("GPL");