15 files changed, 461 insertions, 234 deletions

diff --git a/drivers/acpi/acpi_tad.c b/drivers/acpi/acpi_tad.c
index 33418dd6768a..c9487c5bb7b3 100644
--- a/drivers/acpi/acpi_tad.c
+++ b/drivers/acpi/acpi_tad.c
@@ -90,19 +90,18 @@ static int acpi_tad_set_real_time(struct device *dev, struct acpi_tad_rt *rt)
 	args[0].buffer.pointer = (u8 *)rt;
 	args[0].buffer.length = sizeof(*rt);
 
-	pm_runtime_get_sync(dev);
+	ACQUIRE(pm_runtime_active_try, pm)(dev);
+	if (ACQUIRE_ERR(pm_runtime_active_try, &pm))
+		return -ENXIO;
 
 	status = acpi_evaluate_integer(handle, "_SRT", &arg_list, &retval);
-
-	pm_runtime_put_sync(dev);
-
 	if (ACPI_FAILURE(status) || retval)
 		return -EIO;
 
 	return 0;
 }
 
-static int acpi_tad_get_real_time(struct device *dev, struct acpi_tad_rt *rt)
+static int acpi_tad_evaluate_grt(struct device *dev, struct acpi_tad_rt *rt)
 {
 	acpi_handle handle = ACPI_HANDLE(dev);
 	struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER };
@@ -111,12 +110,7 @@ static int acpi_tad_get_real_time(struct device *dev, struct acpi_tad_rt *rt)
 	acpi_status status;
 	int ret = -EIO;
 
-	pm_runtime_get_sync(dev);
-
 	status = acpi_evaluate_object(handle, "_GRT", NULL, &output);
-
-	pm_runtime_put_sync(dev);
-
 	if (ACPI_FAILURE(status))
 		goto out_free;
 
@@ -139,6 +133,21 @@ out_free:
 	return ret;
 }
 
+static int acpi_tad_get_real_time(struct device *dev, struct acpi_tad_rt *rt)
+{
+	int ret;
+
+	ACQUIRE(pm_runtime_active_try, pm)(dev);
+	if (ACQUIRE_ERR(pm_runtime_active_try, &pm))
+		return -ENXIO;
+
+	ret = acpi_tad_evaluate_grt(dev, rt);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 static char *acpi_tad_rt_next_field(char *s, int *val)
 {
 	char *p;
@@ -266,12 +275,11 @@ static int acpi_tad_wake_set(struct device *dev, char *method, u32 timer_id,
 	args[0].integer.value = timer_id;
 	args[1].integer.value = value;
 
-	pm_runtime_get_sync(dev);
+	ACQUIRE(pm_runtime_active_try, pm)(dev);
+	if (ACQUIRE_ERR(pm_runtime_active_try, &pm))
+		return -ENXIO;
 
 	status = acpi_evaluate_integer(handle, method, &arg_list, &retval);
-
-	pm_runtime_put_sync(dev);
-
 	if (ACPI_FAILURE(status) || retval)
 		return -EIO;
 
@@ -314,12 +322,11 @@ static ssize_t acpi_tad_wake_read(struct device *dev, char *buf, char *method,
 
 	args[0].integer.value = timer_id;
 
-	pm_runtime_get_sync(dev);
+	ACQUIRE(pm_runtime_active_try, pm)(dev);
+	if (ACQUIRE_ERR(pm_runtime_active_try, &pm))
+		return -ENXIO;
 
 	status = acpi_evaluate_integer(handle, method, &arg_list, &retval);
-
-	pm_runtime_put_sync(dev);
-
 	if (ACPI_FAILURE(status))
 		return -EIO;
 
@@ -370,12 +377,11 @@ static int acpi_tad_clear_status(struct device *dev, u32 timer_id)
 
 	args[0].integer.value = timer_id;
 
-	pm_runtime_get_sync(dev);
+	ACQUIRE(pm_runtime_active_try, pm)(dev);
+	if (ACQUIRE_ERR(pm_runtime_active_try, &pm))
+		return -ENXIO;
 
 	status = acpi_evaluate_integer(handle, "_CWS", &arg_list, &retval);
-
-	pm_runtime_put_sync(dev);
-
 	if (ACPI_FAILURE(status) || retval)
 		return -EIO;
 
@@ -411,12 +417,11 @@ static ssize_t acpi_tad_status_read(struct device *dev, char *buf, u32 timer_id)
 
 	args[0].integer.value = timer_id;
 
-	pm_runtime_get_sync(dev);
+	ACQUIRE(pm_runtime_active_try, pm)(dev);
+	if (ACQUIRE_ERR(pm_runtime_active_try, &pm))
+		return -ENXIO;
 
 	status = acpi_evaluate_integer(handle, "_GWS", &arg_list, &retval);
-
-	pm_runtime_put_sync(dev);
-
 	if (ACPI_FAILURE(status))
 		return -EIO;
 
@@ -563,8 +568,6 @@ static void acpi_tad_remove(struct platform_device *pdev)
 
 	device_init_wakeup(dev, false);
 
-	pm_runtime_get_sync(dev);
-
 	if (dd->capabilities & ACPI_TAD_RT)
 		sysfs_remove_group(&dev->kobj, &acpi_tad_time_attr_group);
 
@@ -573,14 +576,16 @@ static void acpi_tad_remove(struct platform_device *pdev)
 
 	sysfs_remove_group(&dev->kobj, &acpi_tad_attr_group);
 
-	acpi_tad_disable_timer(dev, ACPI_TAD_AC_TIMER);
-	acpi_tad_clear_status(dev, ACPI_TAD_AC_TIMER);
-	if (dd->capabilities & ACPI_TAD_DC_WAKE) {
-		acpi_tad_disable_timer(dev, ACPI_TAD_DC_TIMER);
-		acpi_tad_clear_status(dev, ACPI_TAD_DC_TIMER);
+	scoped_guard(pm_runtime_noresume, dev) {
+		acpi_tad_disable_timer(dev, ACPI_TAD_AC_TIMER);
+		acpi_tad_clear_status(dev, ACPI_TAD_AC_TIMER);
+		if (dd->capabilities & ACPI_TAD_DC_WAKE) {
+			acpi_tad_disable_timer(dev, ACPI_TAD_DC_TIMER);
+			acpi_tad_clear_status(dev, ACPI_TAD_DC_TIMER);
+		}
 	}
 
-	pm_runtime_put_sync(dev);
+	pm_runtime_suspend(dev);
 	pm_runtime_disable(dev);
 	acpi_remove_cmos_rtc_space_handler(handle);
 }
diff --git a/drivers/acpi/acpica/nswalk.c b/drivers/acpi/acpica/nswalk.c
index a2ac06a26e92..5670ff5a43cd 100644
--- a/drivers/acpi/acpica/nswalk.c
+++ b/drivers/acpi/acpica/nswalk.c
@@ -169,9 +169,12 @@ acpi_ns_walk_namespace(acpi_object_type type,
 
 	if (start_node == ACPI_ROOT_OBJECT) {
 		start_node = acpi_gbl_root_node;
-		if (!start_node) {
-			return_ACPI_STATUS(AE_NO_NAMESPACE);
-		}
+	}
+
+	/* Avoid walking the namespace if the StartNode is NULL */
+
+	if (!start_node) {
+		return_ACPI_STATUS(AE_NO_NAMESPACE);
 	}
 
 	/* Null child means "get first node" */
diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index 67b76492c839..34181fa52e93 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -91,7 +91,6 @@ enum {
 };
 
 struct acpi_battery {
-	struct mutex lock;
 	struct mutex update_lock;
 	struct power_supply *bat;
 	struct power_supply_desc bat_desc;
@@ -535,11 +534,9 @@ static int acpi_battery_get_info(struct acpi_battery *battery)
 		struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 		acpi_status status = AE_ERROR;
 
-		mutex_lock(&battery->lock);
 		status = acpi_evaluate_object(battery->device->handle,
 					      use_bix ? "_BIX":"_BIF",
 					      NULL, &buffer);
-		mutex_unlock(&battery->lock);
 
 		if (ACPI_FAILURE(status)) {
 			acpi_handle_info(battery->device->handle,
@@ -576,11 +573,8 @@ static int acpi_battery_get_state(struct acpi_battery *battery)
 			msecs_to_jiffies(cache_time)))
 		return 0;
 
-	mutex_lock(&battery->lock);
 	status = acpi_evaluate_object(battery->device->handle, "_BST",
 				      NULL, &buffer);
-	mutex_unlock(&battery->lock);
-
 	if (ACPI_FAILURE(status)) {
 		acpi_handle_info(battery->device->handle,
 				 "_BST evaluation failed: %s",
@@ -628,11 +622,8 @@ static int acpi_battery_set_alarm(struct acpi_battery *battery)
 	    !test_bit(ACPI_BATTERY_ALARM_PRESENT, &battery->flags))
 		return -ENODEV;
 
-	mutex_lock(&battery->lock);
 	status = acpi_execute_simple_method(battery->device->handle, "_BTP",
 					    battery->alarm);
-	mutex_unlock(&battery->lock);
-
 	if (ACPI_FAILURE(status))
 		return -ENODEV;
 
@@ -1235,9 +1226,6 @@ static int acpi_battery_add(struct acpi_device *device)
 	strscpy(acpi_device_name(device), ACPI_BATTERY_DEVICE_NAME);
 	strscpy(acpi_device_class(device), ACPI_BATTERY_CLASS);
 	device->driver_data = battery;
-	result = devm_mutex_init(&device->dev, &battery->lock);
-	if (result)
-		return result;
 
 	result = devm_mutex_init(&device->dev, &battery->update_lock);
 	if (result)
diff --git a/drivers/acpi/dptf/dptf_pch_fivr.c b/drivers/acpi/dptf/dptf_pch_fivr.c
index 952216c67d58..8d7e555929d3 100644
--- a/drivers/acpi/dptf/dptf_pch_fivr.c
+++ b/drivers/acpi/dptf/dptf_pch_fivr.c
@@ -41,7 +41,7 @@ static int pch_fivr_read(acpi_handle handle, char *method, struct pch_fivr_resp
 	ret = 0;
 
 release_buffer:
-	kfree(buffer.pointer);
+	ACPI_FREE(buffer.pointer);
 	return ret;
 }
 
diff --git a/drivers/acpi/fan.h b/drivers/acpi/fan.h
index bedbab0e8e4e..f85f9a0fbfcd 100644
--- a/drivers/acpi/fan.h
+++ b/drivers/acpi/fan.h
@@ -11,6 +11,7 @@
 #define _ACPI_FAN_H_
 
 #include <linux/kconfig.h>
+#include <linux/limits.h>
 
 #define ACPI_FAN_DEVICE_IDS	\
 	{"INT3404", }, /* Fan */ \
@@ -55,19 +56,58 @@ struct acpi_fan {
 	struct acpi_fan_fif fif;
 	struct acpi_fan_fps *fps;
 	int fps_count;
+	/* A value of 0 means that trippoint-related functions are not supported */
+	u32 fan_trip_granularity;
+#if IS_REACHABLE(CONFIG_HWMON)
+	struct device *hdev;
+#endif
 	struct thermal_cooling_device *cdev;
 	struct device_attribute fst_speed;
 	struct device_attribute fine_grain_control;
 };
 
+/**
+ * acpi_fan_speed_valid - Check if fan speed value is valid
+ * @speeed: Speed value returned by the ACPI firmware
+ *
+ * Check if the fan speed value returned by the ACPI firmware is valid. This function is
+ * necessary as ACPI firmware implementations can return 0xFFFFFFFF to signal that the
+ * ACPI fan does not support speed reporting. Additionally, some buggy ACPI firmware
+ * implementations return a value larger than the 32-bit integer value defined by
+ * the ACPI specification when using placeholder values. Such invalid values are also
+ * detected by this function.
+ *
+ * Returns: True if the fan speed value is valid, false otherwise.
+ */
+static inline bool acpi_fan_speed_valid(u64 speed)
+{
+	return speed < U32_MAX;
+}
+
+/**
+ * acpi_fan_power_valid - Check if fan power value is valid
+ * @power: Power value returned by the ACPI firmware
+ *
+ * Check if the fan power value returned by the ACPI firmware is valid.
+ * See acpi_fan_speed_valid() for details.
+ *
+ * Returns: True if the fan power value is valid, false otherwise.
+ */
+static inline bool acpi_fan_power_valid(u64 power)
+{
+	return power < U32_MAX;
+}
+
 int acpi_fan_get_fst(acpi_handle handle, struct acpi_fan_fst *fst);
 int acpi_fan_create_attributes(struct acpi_device *device);
 void acpi_fan_delete_attributes(struct acpi_device *device);
 
 #if IS_REACHABLE(CONFIG_HWMON)
 int devm_acpi_fan_create_hwmon(struct device *dev);
+void acpi_fan_notify_hwmon(struct device *dev);
 #else
 static inline int devm_acpi_fan_create_hwmon(struct device *dev) { return 0; };
+static inline void acpi_fan_notify_hwmon(struct device *dev) { };
 #endif
 
 #endif
diff --git a/drivers/acpi/fan_core.c b/drivers/acpi/fan_core.c
index 46e7fe7a506d..fb08b8549ed7 100644
--- a/drivers/acpi/fan_core.c
+++ b/drivers/acpi/fan_core.c
@@ -7,11 +7,16 @@
  *  Copyright (C) 2022 Intel Corporation. All rights reserved.
  */
 
+#include <linux/bits.h>
 #include <linux/kernel.h>
+#include <linux/limits.h>
+#include <linux/math.h>
+#include <linux/math64.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/uaccess.h>
+#include <linux/uuid.h>
 #include <linux/thermal.h>
 #include <linux/acpi.h>
 #include <linux/platform_device.h>
@@ -19,6 +24,26 @@
 
 #include "fan.h"
 
+#define ACPI_FAN_NOTIFY_STATE_CHANGED	0x80
+
+/*
+ * Defined inside the "Fan Noise Signal" section at
+ * https://learn.microsoft.com/en-us/windows-hardware/design/device-experiences/design-guide.
+ */
+static const guid_t acpi_fan_microsoft_guid = GUID_INIT(0xA7611840, 0x99FE, 0x41AE, 0xA4, 0x88,
+							0x35, 0xC7, 0x59, 0x26, 0xC8, 0xEB);
+#define ACPI_FAN_DSM_GET_TRIP_POINT_GRANULARITY 1
+#define ACPI_FAN_DSM_SET_TRIP_POINTS		2
+#define ACPI_FAN_DSM_GET_OPERATING_RANGES	3
+
+/*
+ * Ensures that fans with a very low trip point granularity
+ * do not send too many notifications.
+ */
+static uint min_trip_distance = 100;
+module_param(min_trip_distance, uint, 0);
+MODULE_PARM_DESC(min_trip_distance, "Minimum distance between fan speed trip points in RPM");
+
 static const struct acpi_device_id fan_device_ids[] = {
 	ACPI_FAN_DEVICE_IDS,
 	{"", 0},
@@ -308,6 +333,182 @@ err:
 	return status;
 }
 
+static int acpi_fan_dsm_init(struct device *dev)
+{
+	union acpi_object dummy = {
+		.package = {
+			.type = ACPI_TYPE_PACKAGE,
+			.count = 0,
+			.elements = NULL,
+		},
+	};
+	struct acpi_fan *fan = dev_get_drvdata(dev);
+	union acpi_object *obj;
+	int ret = 0;
+
+	if (!acpi_check_dsm(fan->handle, &acpi_fan_microsoft_guid, 0,
+			    BIT(ACPI_FAN_DSM_GET_TRIP_POINT_GRANULARITY) |
+			    BIT(ACPI_FAN_DSM_SET_TRIP_POINTS)))
+		return 0;
+
+	dev_info(dev, "Using Microsoft fan extensions\n");
+
+	obj = acpi_evaluate_dsm_typed(fan->handle, &acpi_fan_microsoft_guid, 0,
+				      ACPI_FAN_DSM_GET_TRIP_POINT_GRANULARITY, &dummy,
+				      ACPI_TYPE_INTEGER);
+	if (!obj)
+		return -EIO;
+
+	if (obj->integer.value > U32_MAX)
+		ret = -EOVERFLOW;
+	else
+		fan->fan_trip_granularity = obj->integer.value;
+
+	kfree(obj);
+
+	return ret;
+}
+
+static int acpi_fan_dsm_set_trip_points(struct device *dev, u64 upper, u64 lower)
+{
+	union acpi_object args[2] = {
+		{
+			.integer = {
+				.type = ACPI_TYPE_INTEGER,
+				.value = lower,
+			},
+		},
+		{
+			.integer = {
+				.type = ACPI_TYPE_INTEGER,
+				.value = upper,
+			},
+		},
+	};
+	struct acpi_fan *fan = dev_get_drvdata(dev);
+	union acpi_object in = {
+		.package = {
+			.type = ACPI_TYPE_PACKAGE,
+			.count = ARRAY_SIZE(args),
+			.elements = args,
+		},
+	};
+	union acpi_object *obj;
+
+	obj = acpi_evaluate_dsm(fan->handle, &acpi_fan_microsoft_guid, 0,
+				ACPI_FAN_DSM_SET_TRIP_POINTS, &in);
+	kfree(obj);
+
+	return 0;
+}
+
+static int acpi_fan_dsm_start(struct device *dev)
+{
+	struct acpi_fan *fan = dev_get_drvdata(dev);
+	int ret;
+
+	if (!fan->fan_trip_granularity)
+		return 0;
+
+	/*
+	 * Some firmware implementations only update the values returned by the
+	 * _FST control method when a notification is received. This usually
+	 * works with Microsoft Windows as setting up trip points will keep
+	 * triggering said notifications, but will cause issues when using _FST
+	 * without the Microsoft-specific trip point extension.
+	 *
+	 * Because of this, an initial notification needs to be triggered to
+	 * start the cycle of trip points updates. This is achieved by setting
+	 * the trip points sequencially to two separate ranges. As by the
+	 * Microsoft specification the firmware should trigger a notification
+	 * immediately if the fan speed is outside the trip point range. This
+	 * _should_ result in at least one notification as both ranges do not
+	 * overlap, meaning that the current fan speed needs to be outside at
+	 * least one range.
+	 */
+	ret = acpi_fan_dsm_set_trip_points(dev, fan->fan_trip_granularity, 0);
+	if (ret < 0)
+		return ret;
+
+	return acpi_fan_dsm_set_trip_points(dev, fan->fan_trip_granularity * 3,
+					    fan->fan_trip_granularity * 2);
+}
+
+static int acpi_fan_dsm_update_trips_points(struct device *dev, struct acpi_fan_fst *fst)
+{
+	struct acpi_fan *fan = dev_get_drvdata(dev);
+	u64 upper, lower;
+
+	if (!fan->fan_trip_granularity)
+		return 0;
+
+	if (!acpi_fan_speed_valid(fst->speed))
+		return -EINVAL;
+
+	upper = roundup_u64(fst->speed + min_trip_distance, fan->fan_trip_granularity);
+	if (fst->speed <= min_trip_distance) {
+		lower = 0;
+	} else {
+		/*
+		 * Valid fan speed values cannot be larger than 32 bit, so
+		 * we can safely assume that no overflow will happen here.
+		 */
+		lower = rounddown((u32)fst->speed - min_trip_distance, fan->fan_trip_granularity);
+	}
+
+	return acpi_fan_dsm_set_trip_points(dev, upper, lower);
+}
+
+static void acpi_fan_notify_handler(acpi_handle handle, u32 event, void *context)
+{
+	struct device *dev = context;
+	struct acpi_fan_fst fst;
+	int ret;
+
+	switch (event) {
+	case ACPI_FAN_NOTIFY_STATE_CHANGED:
+		/*
+		 * The ACPI specification says that we must evaluate _FST when we
+		 * receive an ACPI event indicating that the fan state has changed.
+		 */
+		ret = acpi_fan_get_fst(handle, &fst);
+		if (ret < 0) {
+			dev_err(dev, "Error retrieving current fan status: %d\n", ret);
+		} else {
+			ret = acpi_fan_dsm_update_trips_points(dev, &fst);
+			if (ret < 0)
+				dev_err(dev, "Failed to update trip points: %d\n", ret);
+		}
+
+		acpi_fan_notify_hwmon(dev);
+		acpi_bus_generate_netlink_event("fan", dev_name(dev), event, 0);
+		break;
+	default:
+		dev_dbg(dev, "Unsupported ACPI notification 0x%x\n", event);
+		break;
+	}
+}
+
+static void acpi_fan_notify_remove(void *data)
+{
+	struct acpi_fan *fan = data;
+
+	acpi_remove_notify_handler(fan->handle, ACPI_DEVICE_NOTIFY, acpi_fan_notify_handler);
+}
+
+static int devm_acpi_fan_notify_init(struct device *dev)
+{
+	struct acpi_fan *fan = dev_get_drvdata(dev);
+	acpi_status status;
+
+	status = acpi_install_notify_handler(fan->handle, ACPI_DEVICE_NOTIFY,
+					     acpi_fan_notify_handler, dev);
+	if (ACPI_FAILURE(status))
+		return -EIO;
+
+	return devm_add_action_or_reset(dev, acpi_fan_notify_remove, fan);
+}
+
 static int acpi_fan_probe(struct platform_device *pdev)
 {
 	int result = 0;
@@ -347,10 +548,24 @@ static int acpi_fan_probe(struct platform_device *pdev)
 	}
 
 	if (fan->has_fst) {
+		result = acpi_fan_dsm_init(&pdev->dev);
+		if (result)
+			return result;
+
 		result = devm_acpi_fan_create_hwmon(&pdev->dev);
 		if (result)
 			return result;
 
+		result = devm_acpi_fan_notify_init(&pdev->dev);
+		if (result)
+			return result;
+
+		result = acpi_fan_dsm_start(&pdev->dev);
+		if (result) {
+			dev_err(&pdev->dev, "Failed to start Microsoft fan extensions\n");
+			return result;
+		}
+
 		result = acpi_fan_create_attributes(device);
 		if (result)
 			return result;
@@ -436,8 +651,14 @@ static int acpi_fan_suspend(struct device *dev)
 
 static int acpi_fan_resume(struct device *dev)
 {
-	int result;
 	struct acpi_fan *fan = dev_get_drvdata(dev);
+	int result;
+
+	if (fan->has_fst) {
+		result = acpi_fan_dsm_start(dev);
+		if (result)
+			dev_err(dev, "Failed to start Microsoft fan extensions: %d\n", result);
+	}
 
 	if (fan->acpi4)
 		return 0;
diff --git a/drivers/acpi/fan_hwmon.c b/drivers/acpi/fan_hwmon.c
index 4b2c2007f2d7..d3374f8f524b 100644
--- a/drivers/acpi/fan_hwmon.c
+++ b/drivers/acpi/fan_hwmon.c
@@ -15,10 +15,6 @@
 
 #include "fan.h"
 
-/* Returned when the ACPI fan does not support speed reporting */
-#define FAN_SPEED_UNAVAILABLE	U32_MAX
-#define FAN_POWER_UNAVAILABLE	U32_MAX
-
 static struct acpi_fan_fps *acpi_fan_get_current_fps(struct acpi_fan *fan, u64 control)
 {
 	unsigned int i;
@@ -77,7 +73,7 @@ static umode_t acpi_fan_hwmon_is_visible(const void *drvdata, enum hwmon_sensor_
 			 * when the associated attribute should not be created.
 			 */
 			for (i = 0; i < fan->fps_count; i++) {
-				if (fan->fps[i].power != FAN_POWER_UNAVAILABLE)
+				if (acpi_fan_power_valid(fan->fps[i].power))
 					return 0444;
 			}
 
@@ -106,7 +102,7 @@ static int acpi_fan_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
 	case hwmon_fan:
 		switch (attr) {
 		case hwmon_fan_input:
-			if (fst.speed == FAN_SPEED_UNAVAILABLE)
+			if (!acpi_fan_speed_valid(fst.speed))
 				return -ENODEV;
 
 			if (fst.speed > LONG_MAX)
@@ -134,7 +130,7 @@ static int acpi_fan_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
 			if (!fps)
 				return -EIO;
 
-			if (fps->power == FAN_POWER_UNAVAILABLE)
+			if (!acpi_fan_power_valid(fps->power))
 				return -ENODEV;
 
 			if (fps->power > LONG_MAX / MICROWATT_PER_MILLIWATT)
@@ -166,12 +162,19 @@ static const struct hwmon_chip_info acpi_fan_hwmon_chip_info = {
 	.info = acpi_fan_hwmon_info,
 };
 
+void acpi_fan_notify_hwmon(struct device *dev)
+{
+	struct acpi_fan *fan = dev_get_drvdata(dev);
+
+	hwmon_notify_event(fan->hdev, hwmon_fan, hwmon_fan_input, 0);
+}
+
 int devm_acpi_fan_create_hwmon(struct device *dev)
 {
 	struct acpi_fan *fan = dev_get_drvdata(dev);
-	struct device *hdev;
 
-	hdev = devm_hwmon_device_register_with_info(dev, "acpi_fan", fan, &acpi_fan_hwmon_chip_info,
-						    NULL);
-	return PTR_ERR_OR_ZERO(hdev);
+	fan->hdev = devm_hwmon_device_register_with_info(dev, "acpi_fan", fan,
+							 &acpi_fan_hwmon_chip_info, NULL);
+
+	return PTR_ERR_OR_ZERO(fan->hdev);
 }
diff --git a/drivers/acpi/processor_core.c b/drivers/acpi/processor_core.c
index 9b6b71a2ffb5..a4498357bd16 100644
--- a/drivers/acpi/processor_core.c
+++ b/drivers/acpi/processor_core.c
@@ -54,7 +54,7 @@ static int map_x2apic_id(struct acpi_subtable_header *entry,
 	if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
 		return -ENODEV;
 
-	if (device_declaration && (apic->uid == acpi_id)) {
+	if (apic->uid == acpi_id && (device_declaration || acpi_id < 255)) {
 		*apic_id = apic->local_apic_id;
 		return 0;
 	}
diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index 5d824435b26b..65e779be64ff 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -166,7 +166,8 @@ static int __acpi_processor_start(struct acpi_device *device)
 	if (result && !IS_ENABLED(CONFIG_ACPI_CPU_FREQ_PSS))
 		dev_dbg(&device->dev, "CPPC data invalid or not present\n");
 
-	acpi_processor_power_init(pr);
+	if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
+		acpi_processor_power_init(pr);
 
 	acpi_pss_perf_init(pr);
 
@@ -262,8 +263,6 @@ static int __init acpi_processor_driver_init(void)
 	if (result < 0)
 		return result;
 
-	acpi_processor_register_idle_driver();
-
 	result = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
 				   "acpi/cpu-drv:online",
 				   acpi_soft_cpu_online, NULL);
@@ -302,7 +301,6 @@ static void __exit acpi_processor_driver_exit(void)
 
 	cpuhp_remove_state_nocalls(hp_online);
 	cpuhp_remove_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD);
-	acpi_processor_unregister_idle_driver();
 	driver_unregister(&acpi_processor_driver);
 }
 
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 22b051b94a86..89f2f08b2554 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -51,7 +51,7 @@ module_param(latency_factor, uint, 0644);
 
 static DEFINE_PER_CPU(struct cpuidle_device *, acpi_cpuidle_device);
 
-static struct cpuidle_driver acpi_idle_driver = {
+struct cpuidle_driver acpi_idle_driver = {
 	.name =		"acpi_idle",
 	.owner =	THIS_MODULE,
 };
@@ -732,18 +732,16 @@ static int __cpuidle acpi_idle_enter_s2idle(struct cpuidle_device *dev,
 	return 0;
 }
 
-static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
-					   struct cpuidle_device *dev)
+static void acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
+					    struct cpuidle_device *dev)
 {
 	int i, count = ACPI_IDLE_STATE_START;
 	struct acpi_processor_cx *cx;
-	struct cpuidle_state *state;
 
 	if (max_cstate == 0)
 		max_cstate = 1;
 
 	for (i = 1; i < ACPI_PROCESSOR_MAX_POWER && i <= max_cstate; i++) {
-		state = &acpi_idle_driver.states[count];
 		cx = &pr->power.states[i];
 
 		if (!cx->valid)
@@ -751,27 +749,13 @@ static int acpi_processor_setup_cpuidle_cx(struct acpi_processor *pr,
 
 		per_cpu(acpi_cstate[count], dev->cpu) = cx;
 
-		if (lapic_timer_needs_broadcast(pr, cx))
-			state->flags |= CPUIDLE_FLAG_TIMER_STOP;
-
-		if (cx->type == ACPI_STATE_C3) {
-			state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;
-			if (pr->flags.bm_check)
-				state->flags |= CPUIDLE_FLAG_RCU_IDLE;
-		}
-
 		count++;
 		if (count == CPUIDLE_STATE_MAX)
 			break;
 	}
-
-	if (!count)
-		return -EINVAL;
-
-	return 0;
 }
 
-static int acpi_processor_setup_cstates(struct acpi_processor *pr)
+static void acpi_processor_setup_cstates(struct acpi_processor *pr)
 {
 	int i, count;
 	struct acpi_processor_cx *cx;
@@ -818,17 +802,21 @@ static int acpi_processor_setup_cstates(struct acpi_processor *pr)
 		if (cx->type != ACPI_STATE_C1 && !acpi_idle_fallback_to_c1(pr))
 			state->enter_s2idle = acpi_idle_enter_s2idle;
 
+		if (lapic_timer_needs_broadcast(pr, cx))
+			state->flags |= CPUIDLE_FLAG_TIMER_STOP;
+
+		if (cx->type == ACPI_STATE_C3) {
+			state->flags |= CPUIDLE_FLAG_TLB_FLUSHED;
+			if (pr->flags.bm_check)
+				state->flags |= CPUIDLE_FLAG_RCU_IDLE;
+		}
+
 		count++;
 		if (count == CPUIDLE_STATE_MAX)
 			break;
 	}
 
 	drv->state_count = count;
-
-	if (!count)
-		return -EINVAL;
-
-	return 0;
 }
 
 static inline void acpi_processor_cstate_first_run_checks(void)
@@ -1243,7 +1231,8 @@ static int acpi_processor_setup_cpuidle_states(struct acpi_processor *pr)
 	if (pr->flags.has_lpi)
 		return acpi_processor_setup_lpi_states(pr);
 
-	return acpi_processor_setup_cstates(pr);
+	acpi_processor_setup_cstates(pr);
+	return 0;
 }
 
 /**
@@ -1263,7 +1252,8 @@ static int acpi_processor_setup_cpuidle_dev(struct acpi_processor *pr,
 	if (pr->flags.has_lpi)
 		return acpi_processor_ffh_lpi_probe(pr->id);
 
-	return acpi_processor_setup_cpuidle_cx(pr, dev);
+	acpi_processor_setup_cpuidle_cx(pr, dev);
+	return 0;
 }
 
 static int acpi_processor_get_power_info(struct acpi_processor *pr)
@@ -1357,102 +1347,79 @@ int acpi_processor_power_state_has_changed(struct acpi_processor *pr)
 	return 0;
 }
 
-void acpi_processor_register_idle_driver(void)
-{
-	struct acpi_processor *pr;
-	int ret = -ENODEV;
-	int cpu;
-
-	/*
-	 * Acpi idle driver is used by all possible CPUs.
-	 * Install the idle handler by the processor power info of one in them.
-	 * Note that we use previously set idle handler will be used on
-	 * platforms that only support C1.
-	 */
-	for_each_cpu(cpu, (struct cpumask *)cpu_possible_mask) {
-		pr = per_cpu(processors, cpu);
-		if (!pr)
-			continue;
-
-		ret = acpi_processor_get_power_info(pr);
-		if (!ret) {
-			pr->flags.power_setup_done = 1;
-			acpi_processor_setup_cpuidle_states(pr);
-			break;
-		}
-	}
-
-	if (ret) {
-		pr_debug("No ACPI power information from any CPUs.\n");
-		return;
-	}
-
-	ret = cpuidle_register_driver(&acpi_idle_driver);
-	if (ret) {
-		pr_debug("register %s failed.\n", acpi_idle_driver.name);
-		return;
-	}
-	pr_debug("%s registered with cpuidle.\n", acpi_idle_driver.name);
-}
-
-void acpi_processor_unregister_idle_driver(void)
-{
-	cpuidle_unregister_driver(&acpi_idle_driver);
-}
+static int acpi_processor_registered;
 
-void acpi_processor_power_init(struct acpi_processor *pr)
+int acpi_processor_power_init(struct acpi_processor *pr)
 {
+	int retval;
 	struct cpuidle_device *dev;
 
-	/*
-	 * The code below only works if the current cpuidle driver is the ACPI
-	 * idle driver.
-	 */
-	if (cpuidle_get_driver() != &acpi_idle_driver)
-		return;
-
 	if (disabled_by_idle_boot_param())
-		return;
+		return 0;
 
 	acpi_processor_cstate_first_run_checks();
 
 	if (!acpi_processor_get_power_info(pr))
 		pr->flags.power_setup_done = 1;
 
-	if (!pr->flags.power)
-		return;
-
-	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
-	if (!dev)
-		return;
+	/*
+	 * Install the idle handler if processor power management is supported.
+	 * Note that we use previously set idle handler will be used on
+	 * platforms that only support C1.
+	 */
+	if (pr->flags.power) {
+		/* Register acpi_idle_driver if not already registered */
+		if (!acpi_processor_registered) {
+			acpi_processor_setup_cpuidle_states(pr);
+			retval = cpuidle_register_driver(&acpi_idle_driver);
+			if (retval)
+				return retval;
+			pr_debug("%s registered with cpuidle\n",
+				 acpi_idle_driver.name);
+		}
 
-	per_cpu(acpi_cpuidle_device, pr->id) = dev;
+		dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+		if (!dev)
+			return -ENOMEM;
+		per_cpu(acpi_cpuidle_device, pr->id) = dev;
 
-	acpi_processor_setup_cpuidle_dev(pr, dev);
+		acpi_processor_setup_cpuidle_dev(pr, dev);
 
-	/*
-	 * Register a cpuidle device for this CPU.  The cpuidle driver using
-	 * this device is expected to be registered.
-	 */
-	if (cpuidle_register_device(dev)) {
-		per_cpu(acpi_cpuidle_device, pr->id) = NULL;
-		kfree(dev);
+		/* Register per-cpu cpuidle_device. Cpuidle driver
+		 * must already be registered before registering device
+		 */
+		retval = cpuidle_register_device(dev);
+		if (retval) {
+			if (acpi_processor_registered == 0)
+				cpuidle_unregister_driver(&acpi_idle_driver);
+
+			per_cpu(acpi_cpuidle_device, pr->id) = NULL;
+			kfree(dev);
+			return retval;
+		}
+		acpi_processor_registered++;
 	}
+	return 0;
 }
 
-void acpi_processor_power_exit(struct acpi_processor *pr)
+int acpi_processor_power_exit(struct acpi_processor *pr)
 {
 	struct cpuidle_device *dev = per_cpu(acpi_cpuidle_device, pr->id);
 
 	if (disabled_by_idle_boot_param())
-		return;
+		return 0;
 
 	if (pr->flags.power) {
 		cpuidle_unregister_device(dev);
+		acpi_processor_registered--;
+		if (acpi_processor_registered == 0)
+			cpuidle_unregister_driver(&acpi_idle_driver);
+
 		kfree(dev);
 	}
 
 	pr->flags.power_setup_done = 0;
+	return 0;
 }
 
 MODULE_IMPORT_NS("ACPI_PROCESSOR_IDLE");
diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c
index 43d5e457814e..18e90067d567 100644
--- a/drivers/acpi/property.c
+++ b/drivers/acpi/property.c
@@ -1280,7 +1280,7 @@ static int acpi_data_prop_read(const struct acpi_device_data *data,
 		ret = acpi_copy_property_array_uint(items, (u64 *)val, nval);
 		break;
 	case DEV_PROP_STRING:
-		nval = min_t(u32, nval, obj->package.count);
+		nval = min(nval, obj->package.count);
 		if (nval == 0)
 			return -ENODATA;
 
@@ -1329,13 +1329,14 @@ static int stop_on_next(struct acpi_device *adev, void *data)
 	return 0;
 }
 
-/**
+/*
  * acpi_get_next_subnode - Return the next child node handle for a fwnode
  * @fwnode: Firmware node to find the next child node for.
  * @child: Handle to one of the device's child nodes or a null handle.
  */
-struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
-					    struct fwnode_handle *child)
+static struct fwnode_handle *
+acpi_get_next_subnode(const struct fwnode_handle *fwnode,
+		      struct fwnode_handle *child)
 {
 	struct acpi_device *adev = to_acpi_device_node(fwnode);
 
@@ -1472,7 +1473,7 @@ static struct fwnode_handle *acpi_graph_get_next_endpoint(
 
 	if (!prev) {
 		do {
-			port = fwnode_get_next_child_node(fwnode, port);
+			port = acpi_get_next_subnode(fwnode, port);
 			/*
 			 * The names of the port nodes begin with "port@"
 			 * followed by the number of the port node and they also
@@ -1490,14 +1491,17 @@ static struct fwnode_handle *acpi_graph_get_next_endpoint(
 	if (!port)
 		return NULL;
 
-	endpoint = fwnode_get_next_child_node(port, prev);
-	while (!endpoint) {
-		port = fwnode_get_next_child_node(fwnode, port);
-		if (!port)
+	do {
+		endpoint = acpi_get_next_subnode(port, prev);
+		if (endpoint)
 			break;
-		if (is_acpi_graph_node(port, "port"))
-			endpoint = fwnode_get_next_child_node(port, NULL);
-	}
+
+		prev = NULL;
+
+		do {
+			port = acpi_get_next_subnode(fwnode, port);
+		} while (port && !is_acpi_graph_node(port, "port"));
+	} while (port);
 
 	/*
 	 * The names of the endpoint nodes begin with "endpoint@" followed by
@@ -1714,6 +1718,7 @@ static int acpi_fwnode_graph_parse_endpoint(const struct fwnode_handle *fwnode,
 	if (fwnode_property_read_u32(fwnode, "reg", &endpoint->id))
 		fwnode_property_read_u32(fwnode, "endpoint", &endpoint->id);
 
+	fwnode_handle_put(port_fwnode);
 	return 0;
 }
 
diff --git a/drivers/acpi/sleep.h b/drivers/acpi/sleep.h
index d960a238be4e..9c3cb109c5d2 100644
--- a/drivers/acpi/sleep.h
+++ b/drivers/acpi/sleep.h
@@ -17,10 +17,7 @@ static inline acpi_status acpi_set_waking_vector(u32 wakeup_address)
 
 extern int acpi_s2idle_begin(void);
 extern int acpi_s2idle_prepare(void);
-extern int acpi_s2idle_prepare_late(void);
-extern void acpi_s2idle_check(void);
 extern bool acpi_s2idle_wake(void);
-extern void acpi_s2idle_restore_early(void);
 extern void acpi_s2idle_restore(void);
 extern void acpi_s2idle_end(void);
 
diff --git a/drivers/acpi/x86/s2idle.c b/drivers/acpi/x86/s2idle.c
index dd0b40b9bbe8..6d4d06236f61 100644
--- a/drivers/acpi/x86/s2idle.c
+++ b/drivers/acpi/x86/s2idle.c
@@ -299,34 +299,13 @@ free_acpi_buffer:
 	ACPI_FREE(out_obj);
 }
 
-/**
- * acpi_get_lps0_constraint - Get the LPS0 constraint for a device.
- * @adev: Device to get the constraint for.
- *
- * The LPS0 constraint is the shallowest (minimum) power state in which the
- * device can be so as to allow the platform as a whole to achieve additional
- * energy conservation by utilizing a system-wide low-power state.
- *
- * Returns:
- *  - ACPI power state value of the constraint for @adev on success.
- *  - Otherwise, ACPI_STATE_UNKNOWN.
- */
-int acpi_get_lps0_constraint(struct acpi_device *adev)
-{
-	struct lpi_constraints *entry;
-
-	for_each_lpi_constraint(entry) {
-		if (adev->handle == entry->handle)
-			return entry->min_dstate;
-	}
-
-	return ACPI_STATE_UNKNOWN;
-}
-
 static void lpi_check_constraints(void)
 {
 	struct lpi_constraints *entry;
 
+	if (IS_ERR_OR_NULL(lpi_constraints_table))
+		return;
+
 	for_each_lpi_constraint(entry) {
 		struct acpi_device *adev = acpi_fetch_acpi_dev(entry->handle);
 
@@ -508,11 +487,6 @@ static int lps0_device_attach(struct acpi_device *adev,
 
 	lps0_device_handle = adev->handle;
 
-	if (acpi_s2idle_vendor_amd())
-		lpi_device_get_constraints_amd();
-	else
-		lpi_device_get_constraints();
-
 	/*
 	 * Use suspend-to-idle by default if ACPI_FADT_LOW_POWER_S0 is set in
 	 * the FADT and the default suspend mode was not set from the command
@@ -539,7 +513,26 @@ static struct acpi_scan_handler lps0_handler = {
 	.attach = lps0_device_attach,
 };
 
-int acpi_s2idle_prepare_late(void)
+static int acpi_s2idle_begin_lps0(void)
+{
+	if (pm_debug_messages_on && !lpi_constraints_table) {
+		if (acpi_s2idle_vendor_amd())
+			lpi_device_get_constraints_amd();
+		else
+			lpi_device_get_constraints();
+
+		/*
+		 * Try to retrieve the constraints only once because failures
+		 * to do so usually are sticky.
+		 */
+		if (!lpi_constraints_table)
+			lpi_constraints_table = ERR_PTR(-ENODATA);
+	}
+
+	return acpi_s2idle_begin();
+}
+
+static int acpi_s2idle_prepare_late_lps0(void)
 {
 	struct acpi_s2idle_dev_ops *handler;
 
@@ -585,7 +578,7 @@ int acpi_s2idle_prepare_late(void)
 	return 0;
 }
 
-void acpi_s2idle_check(void)
+static void acpi_s2idle_check_lps0(void)
 {
 	struct acpi_s2idle_dev_ops *handler;
 
@@ -598,7 +591,7 @@ void acpi_s2idle_check(void)
 	}
 }
 
-void acpi_s2idle_restore_early(void)
+static void acpi_s2idle_restore_early_lps0(void)
 {
 	struct acpi_s2idle_dev_ops *handler;
 
@@ -636,12 +629,12 @@ void acpi_s2idle_restore_early(void)
 }
 
 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
-	.begin = acpi_s2idle_begin,
+	.begin = acpi_s2idle_begin_lps0,
 	.prepare = acpi_s2idle_prepare,
-	.prepare_late = acpi_s2idle_prepare_late,
-	.check = acpi_s2idle_check,
+	.prepare_late = acpi_s2idle_prepare_late_lps0,
+	.check = acpi_s2idle_check_lps0,
 	.wake = acpi_s2idle_wake,
-	.restore_early = acpi_s2idle_restore_early,
+	.restore_early = acpi_s2idle_restore_early_lps0,
 	.restore = acpi_s2idle_restore,
 	.end = acpi_s2idle_end,
 };
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index 7146a8e9e9c2..d0eccbd920e5 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -417,15 +417,32 @@ static inline void acpi_processor_throttling_init(void) {}
 #endif	/* CONFIG_ACPI_CPU_FREQ_PSS */
 
 /* in processor_idle.c */
+extern struct cpuidle_driver acpi_idle_driver;
 #ifdef CONFIG_ACPI_PROCESSOR_IDLE
-void acpi_processor_power_init(struct acpi_processor *pr);
-void acpi_processor_power_exit(struct acpi_processor *pr);
+int acpi_processor_power_init(struct acpi_processor *pr);
+int acpi_processor_power_exit(struct acpi_processor *pr);
 int acpi_processor_power_state_has_changed(struct acpi_processor *pr);
 int acpi_processor_hotplug(struct acpi_processor *pr);
-void acpi_processor_register_idle_driver(void);
-void acpi_processor_unregister_idle_driver(void);
-int acpi_processor_ffh_lpi_probe(unsigned int cpu);
-int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi);
+#else
+static inline int acpi_processor_power_init(struct acpi_processor *pr)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_processor_power_exit(struct acpi_processor *pr)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_processor_power_state_has_changed(struct acpi_processor *pr)
+{
+	return -ENODEV;
+}
+
+static inline int acpi_processor_hotplug(struct acpi_processor *pr)
+{
+	return -ENODEV;
+}
 #endif /* CONFIG_ACPI_PROCESSOR_IDLE */
 
 /* in processor_thermal.c */
@@ -448,6 +465,11 @@ static inline void acpi_thermal_cpufreq_exit(struct cpufreq_policy *policy)
 }
 #endif	/* CONFIG_CPU_FREQ */
 
+#ifdef CONFIG_ACPI_PROCESSOR_IDLE
+extern int acpi_processor_ffh_lpi_probe(unsigned int cpu);
+extern int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi);
+#endif
+
 void acpi_processor_init_invariance_cppc(void);
 
 #endif
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 5ff5d99f6ead..41f3bf6e4165 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -1146,12 +1146,7 @@ struct acpi_s2idle_dev_ops {
 #if defined(CONFIG_SUSPEND) && defined(CONFIG_X86)
 int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg);
 void acpi_unregister_lps0_dev(struct acpi_s2idle_dev_ops *arg);
-int acpi_get_lps0_constraint(struct acpi_device *adev);
 #else /* CONFIG_SUSPEND && CONFIG_X86 */
-static inline int acpi_get_lps0_constraint(struct device *dev)
-{
-	return ACPI_STATE_UNKNOWN;
-}
 static inline int acpi_register_lps0_dev(struct acpi_s2idle_dev_ops *arg)
 {
 	return -ENODEV;
@@ -1349,9 +1344,6 @@ acpi_data_add_props(struct acpi_device_data *data, const guid_t *guid,
 int acpi_node_prop_get(const struct fwnode_handle *fwnode, const char *propname,
 		       void **valptr);
 
-struct fwnode_handle *acpi_get_next_subnode(const struct fwnode_handle *fwnode,
-					    struct fwnode_handle *child);
-
 struct acpi_probe_entry;
 typedef bool (*acpi_probe_entry_validate_subtbl)(struct acpi_subtable_header *,
 						 struct acpi_probe_entry *);
@@ -1451,13 +1443,6 @@ static inline int acpi_node_prop_get(const struct fwnode_handle *fwnode,
 }
 
 static inline struct fwnode_handle *
-acpi_get_next_subnode(const struct fwnode_handle *fwnode,
-		      struct fwnode_handle *child)
-{
-	return NULL;
-}
-
-static inline struct fwnode_handle *
 acpi_graph_get_next_endpoint(const struct fwnode_handle *fwnode,
 			     struct fwnode_handle *prev)
 {