ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

12 files changed, 1587 insertions, 0 deletions

diff --git a/tools/lib/thermal/.gitignore b/tools/lib/thermal/.gitignore
new file mode 100644
index 000000000..5d2aeda80
--- /dev/null
+++ b/tools/lib/thermal/.gitignore
@@ -0,0 +1,2 @@
+libthermal.so*
+libthermal.pc
diff --git a/tools/lib/thermal/Build b/tools/lib/thermal/Build
new file mode 100644
index 000000000..4a892d9e2
--- /dev/null
+++ b/tools/lib/thermal/Build
@@ -0,0 +1,5 @@
+libthermal-y += commands.o
+libthermal-y += events.o
+libthermal-y += thermal_nl.o
+libthermal-y += sampling.o
+libthermal-y += thermal.o
diff --git a/tools/lib/thermal/Makefile b/tools/lib/thermal/Makefile
new file mode 100644
index 000000000..41aa7a324
--- /dev/null
+++ b/tools/lib/thermal/Makefile
@@ -0,0 +1,159 @@
+# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+# Most of this file is copied from tools/lib/perf/Makefile
+
+LIBTHERMAL_VERSION = 0
+LIBTHERMAL_PATCHLEVEL = 0
+LIBTHERMAL_EXTRAVERSION = 1
+
+MAKEFLAGS += --no-print-directory
+
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(CURDIR)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+# $(info Determined 'srctree' to be $(srctree))
+endif
+
+INSTALL = install
+
+# Use DESTDIR for installing into a different root directory.
+# This is useful for building a package. The program will be
+# installed in this directory as if it was the root directory.
+# Then the build tool can move it later.
+DESTDIR ?=
+DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'
+
+include $(srctree)/tools/scripts/Makefile.include
+include $(srctree)/tools/scripts/Makefile.arch
+
+ifeq ($(LP64), 1)
+  libdir_relative = lib64
+else
+  libdir_relative = lib
+endif
+
+prefix ?=
+libdir = $(prefix)/$(libdir_relative)
+
+# Shell quotes
+libdir_SQ = $(subst ','\'',$(libdir))
+libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
+
+# Set compile option CFLAGS
+ifdef EXTRA_CFLAGS
+  CFLAGS := $(EXTRA_CFLAGS)
+else
+  CFLAGS := -g -Wall
+endif
+
+NL3_CFLAGS = $(shell pkg-config --cflags libnl-3.0 2>/dev/null)
+ifeq ($(NL3_CFLAGS),)
+NL3_CFLAGS = -I/usr/include/libnl3
+endif
+
+INCLUDES = \
+-I$(srctree)/tools/lib/thermal/include \
+-I$(srctree)/tools/lib/ \
+-I$(srctree)/tools/include \
+-I$(srctree)/tools/arch/$(SRCARCH)/include/ \
+-I$(srctree)/tools/arch/$(SRCARCH)/include/uapi \
+-I$(srctree)/tools/include/uapi
+
+# Append required CFLAGS
+override CFLAGS += $(EXTRA_WARNINGS)
+override CFLAGS += -Werror -Wall
+override CFLAGS += -fPIC
+override CFLAGS += $(NL3_CFLAGS)
+override CFLAGS += $(INCLUDES)
+override CFLAGS += -fvisibility=hidden
+override CFGLAS += -Wl,-L.
+override CFGLAS += -Wl,-lthermal
+
+all:
+
+export srctree OUTPUT CC LD CFLAGS V
+export DESTDIR DESTDIR_SQ
+
+include $(srctree)/tools/build/Makefile.include
+
+VERSION_SCRIPT := libthermal.map
+
+PATCHLEVEL    = $(LIBTHERMAL_PATCHLEVEL)
+EXTRAVERSION  = $(LIBTHERMAL_EXTRAVERSION)
+VERSION       = $(LIBTHERMAL_VERSION).$(LIBTHERMAL_PATCHLEVEL).$(LIBTHERMAL_EXTRAVERSION)
+
+LIBTHERMAL_SO := $(OUTPUT)libthermal.so.$(VERSION)
+LIBTHERMAL_A  := $(OUTPUT)libthermal.a
+LIBTHERMAL_IN := $(OUTPUT)libthermal-in.o
+LIBTHERMAL_PC := $(OUTPUT)libthermal.pc
+LIBTHERMAL_ALL := $(LIBTHERMAL_A) $(OUTPUT)libthermal.so*
+
+THERMAL_UAPI := include/uapi/linux/thermal.h
+
+$(THERMAL_UAPI): FORCE
+	ln -sf $(srctree)/$@ $(srctree)/tools/$@
+
+$(LIBTHERMAL_IN): FORCE
+	$(Q)$(MAKE) $(build)=libthermal
+
+$(LIBTHERMAL_A): $(LIBTHERMAL_IN)
+	$(QUIET_AR)$(RM) $@ && $(AR) rcs $@ $(LIBTHERMAL_IN)
+
+$(LIBTHERMAL_SO): $(LIBTHERMAL_IN)
+	$(QUIET_LINK)$(CC) --shared -Wl,-soname,libthermal.so \
+                                    -Wl,--version-script=$(VERSION_SCRIPT) $^ -o $@
+	@ln -sf $(@F) $(OUTPUT)libthermal.so
+	@ln -sf $(@F) $(OUTPUT)libthermal.so.$(LIBTHERMAL_VERSION)
+
+
+libs: $(THERMAL_UAPI) $(LIBTHERMAL_A) $(LIBTHERMAL_SO) $(LIBTHERMAL_PC)
+
+all: fixdep
+	$(Q)$(MAKE) libs
+
+clean:
+	$(call QUIET_CLEAN, libthermal) $(RM) $(LIBTHERMAL_A) \
+                *.o *~ *.a *.so *.so.$(VERSION) *.so.$(LIBTHERMAL_VERSION) \
+                .*.d .*.cmd LIBTHERMAL-CFLAGS $(LIBTHERMAL_PC) \
+                $(srctree)/tools/$(THERMAL_UAPI)
+
+$(LIBTHERMAL_PC):
+	$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \
+		-e "s|@LIBDIR@|$(libdir_SQ)|" \
+		-e "s|@VERSION@|$(VERSION)|" \
+		< libthermal.pc.template > $@
+
+define do_install_mkdir
+	if [ ! -d '$(DESTDIR_SQ)$1' ]; then             \
+		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$1'; \
+	fi
+endef
+
+define do_install
+	if [ ! -d '$(DESTDIR_SQ)$2' ]; then             \
+		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
+	fi;                                             \
+	$(INSTALL) $1 $(if $3,-m $3,) '$(DESTDIR_SQ)$2'
+endef
+
+install_lib: libs
+	$(call QUIET_INSTALL, $(LIBTHERMAL_ALL)) \
+		$(call do_install_mkdir,$(libdir_SQ)); \
+		cp -fR --preserve=mode,timestamp $(LIBTHERMAL_ALL) $(DESTDIR)$(libdir_SQ)
+
+install_headers:
+	$(call QUIET_INSTALL, headers) \
+		$(call do_install,include/thermal.h,$(prefix)/include/thermal,644); \
+
+install_pkgconfig: $(LIBTHERMAL_PC)
+	$(call QUIET_INSTALL, $(LIBTHERMAL_PC)) \
+		$(call do_install,$(LIBTHERMAL_PC),$(libdir_SQ)/pkgconfig,644)
+
+install_doc:
+	$(Q)$(MAKE) -C Documentation install-man install-html install-examples
+
+install: install_lib install_headers install_pkgconfig
+
+FORCE:
+
+.PHONY: all install clean FORCE
diff --git a/tools/lib/thermal/commands.c b/tools/lib/thermal/commands.c
new file mode 100644
index 000000000..4998cec79
--- /dev/null
+++ b/tools/lib/thermal/commands.c
@@ -0,0 +1,511 @@
+// SPDX-License-Identifier: LGPL-2.1+
+// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
+#define _GNU_SOURCE
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <limits.h>
+
+#include <thermal.h>
+#include "thermal_nl.h"
+
+static struct nla_policy thermal_genl_policy[THERMAL_GENL_ATTR_MAX + 1] = {
+	/* Thermal zone */
+	[THERMAL_GENL_ATTR_TZ]                  = { .type = NLA_NESTED },
+	[THERMAL_GENL_ATTR_TZ_ID]               = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_TEMP]             = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_TRIP]             = { .type = NLA_NESTED },
+	[THERMAL_GENL_ATTR_TZ_TRIP_ID]          = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_TRIP_TEMP]        = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_TRIP_TYPE]        = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_TRIP_HYST]        = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_MODE]             = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_CDEV_WEIGHT]      = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_TZ_NAME]             = { .type = NLA_STRING },
+
+	/* Governor(s) */
+	[THERMAL_GENL_ATTR_TZ_GOV]              = { .type = NLA_NESTED },
+	[THERMAL_GENL_ATTR_TZ_GOV_NAME]         = { .type = NLA_STRING },
+
+	/* Cooling devices */
+	[THERMAL_GENL_ATTR_CDEV]                = { .type = NLA_NESTED },
+	[THERMAL_GENL_ATTR_CDEV_ID]             = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_CDEV_CUR_STATE]      = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_CDEV_MAX_STATE]      = { .type = NLA_U32 },
+	[THERMAL_GENL_ATTR_CDEV_NAME]           = { .type = NLA_STRING },
+
+        /* Thresholds */
+        [THERMAL_GENL_ATTR_THRESHOLD]      	= { .type = NLA_NESTED },
+        [THERMAL_GENL_ATTR_THRESHOLD_TEMP]      = { .type = NLA_U32 },
+        [THERMAL_GENL_ATTR_THRESHOLD_DIRECTION] = { .type = NLA_U32 },
+};
+
+static int parse_tz_get(struct genl_info *info, struct thermal_zone **tz)
+{
+	struct nlattr *attr;
+	struct thermal_zone *__tz = NULL;
+	size_t size = 0;
+	int rem;
+
+	nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_TZ], rem) {
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_ID) {
+
+			size++;
+
+			__tz = realloc(__tz, sizeof(*__tz) * (size + 2));
+			if (!__tz)
+				return THERMAL_ERROR;
+
+			__tz[size - 1].id = nla_get_u32(attr);
+		}
+
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_NAME)
+			nla_strlcpy(__tz[size - 1].name, attr,
+				    THERMAL_NAME_LENGTH);
+	}
+
+	if (__tz)
+		__tz[size].id = -1;
+
+	*tz = __tz;
+
+	return THERMAL_SUCCESS;
+}
+
+static int parse_cdev_get(struct genl_info *info, struct thermal_cdev **cdev)
+{
+	struct nlattr *attr;
+	struct thermal_cdev *__cdev = NULL;
+	size_t size = 0;
+	int rem;
+
+	nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_CDEV], rem) {
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_ID) {
+
+			size++;
+
+			__cdev = realloc(__cdev, sizeof(*__cdev) * (size + 2));
+			if (!__cdev)
+				return THERMAL_ERROR;
+
+			__cdev[size - 1].id = nla_get_u32(attr);
+		}
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_NAME) {
+			nla_strlcpy(__cdev[size - 1].name, attr,
+				    THERMAL_NAME_LENGTH);
+		}
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_CUR_STATE)
+			__cdev[size - 1].cur_state = nla_get_u32(attr);
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_CDEV_MAX_STATE)
+			__cdev[size - 1].max_state = nla_get_u32(attr);
+	}
+
+	if (__cdev)
+		__cdev[size].id = -1;
+
+	*cdev = __cdev;
+
+	return THERMAL_SUCCESS;
+}
+
+static int parse_tz_get_trip(struct genl_info *info, struct thermal_zone *tz)
+{
+	struct nlattr *attr;
+	struct thermal_trip *__tt = NULL;
+	size_t size = 0;
+	int rem;
+
+	nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_TZ_TRIP], rem) {
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_ID) {
+
+			size++;
+
+			__tt = realloc(__tt, sizeof(*__tt) * (size + 2));
+			if (!__tt)
+				return THERMAL_ERROR;
+
+			__tt[size - 1].id = nla_get_u32(attr);
+		}
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_TYPE)
+			__tt[size - 1].type = nla_get_u32(attr);
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_TEMP)
+			__tt[size - 1].temp = nla_get_u32(attr);
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_TZ_TRIP_HYST)
+			__tt[size - 1].hyst = nla_get_u32(attr);
+	}
+
+	if (__tt)
+		__tt[size].id = -1;
+
+	tz->trip = __tt;
+
+	return THERMAL_SUCCESS;
+}
+
+static int parse_tz_get_temp(struct genl_info *info, struct thermal_zone *tz)
+{
+	int id = -1;
+
+	if (info->attrs[THERMAL_GENL_ATTR_TZ_ID])
+		id = nla_get_u32(info->attrs[THERMAL_GENL_ATTR_TZ_ID]);
+
+	if (tz->id != id)
+		return THERMAL_ERROR;
+
+	if (info->attrs[THERMAL_GENL_ATTR_TZ_TEMP])
+		tz->temp = nla_get_u32(info->attrs[THERMAL_GENL_ATTR_TZ_TEMP]);
+
+	return THERMAL_SUCCESS;
+}
+
+static int parse_tz_get_gov(struct genl_info *info, struct thermal_zone *tz)
+{
+	int id = -1;
+
+	if (info->attrs[THERMAL_GENL_ATTR_TZ_ID])
+		id = nla_get_u32(info->attrs[THERMAL_GENL_ATTR_TZ_ID]);
+
+	if (tz->id != id)
+		return THERMAL_ERROR;
+
+	if (info->attrs[THERMAL_GENL_ATTR_TZ_GOV_NAME]) {
+		nla_strlcpy(tz->governor,
+			    info->attrs[THERMAL_GENL_ATTR_TZ_GOV_NAME],
+			    THERMAL_NAME_LENGTH);
+	}
+
+	return THERMAL_SUCCESS;
+}
+
+static int parse_threshold_get(struct genl_info *info, struct thermal_zone *tz)
+{
+	struct nlattr *attr;
+	struct thermal_threshold *__tt = NULL;
+	size_t size = 0;
+	int rem;
+
+	/*
+	 * The size contains the size of the array and we want to
+	 * access the last element, size - 1.
+	 *
+	 * The variable size is initialized to zero but it will be
+	 * then incremented by the first if() statement. The message
+	 * attributes are ordered, so the first if() statement will be
+	 * always called before the second one. If it happens that is
+	 * not the case, then it is a kernel bug.
+	 */
+	nla_for_each_nested(attr, info->attrs[THERMAL_GENL_ATTR_THRESHOLD], rem) {
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_THRESHOLD_TEMP) {
+
+			size++;
+
+			__tt = realloc(__tt, sizeof(*__tt) * (size + 2));
+			if (!__tt)
+				return THERMAL_ERROR;
+
+			__tt[size - 1].temperature = nla_get_u32(attr);
+		}
+
+		if (nla_type(attr) == THERMAL_GENL_ATTR_THRESHOLD_DIRECTION)
+			__tt[size - 1].direction = nla_get_u32(attr);
+	}
+
+	if (__tt)
+		__tt[size].temperature = INT_MAX;
+
+	tz->thresholds = __tt;
+
+	return THERMAL_SUCCESS;
+}
+
+static int handle_netlink(struct nl_cache_ops *unused,
+			  struct genl_cmd *cmd,
+			  struct genl_info *info, void *arg)
+{
+	int ret;
+
+	switch (cmd->c_id) {
+
+	case THERMAL_GENL_CMD_TZ_GET_ID:
+		ret = parse_tz_get(info, arg);
+		break;
+
+	case THERMAL_GENL_CMD_CDEV_GET:
+		ret = parse_cdev_get(info, arg);
+		break;
+
+	case THERMAL_GENL_CMD_TZ_GET_TEMP:
+		ret = parse_tz_get_temp(info, arg);
+		break;
+
+	case THERMAL_GENL_CMD_TZ_GET_TRIP:
+		ret = parse_tz_get_trip(info, arg);
+		break;
+
+	case THERMAL_GENL_CMD_TZ_GET_GOV:
+		ret = parse_tz_get_gov(info, arg);
+		break;
+
+	case THERMAL_GENL_CMD_THRESHOLD_GET:
+		ret = parse_threshold_get(info, arg);
+		break;
+
+	default:
+		return THERMAL_ERROR;
+	}
+
+	return ret;
+}
+
+static struct genl_cmd thermal_cmds[] = {
+	{
+		.c_id		= THERMAL_GENL_CMD_TZ_GET_ID,
+		.c_name		= (char *)"List thermal zones",
+		.c_msg_parser	= handle_netlink,
+		.c_maxattr	= THERMAL_GENL_ATTR_MAX,
+		.c_attr_policy	= thermal_genl_policy,
+	},
+	{
+		.c_id		= THERMAL_GENL_CMD_TZ_GET_GOV,
+		.c_name		= (char *)"Get governor",
+		.c_msg_parser	= handle_netlink,
+		.c_maxattr	= THERMAL_GENL_ATTR_MAX,
+		.c_attr_policy	= thermal_genl_policy,
+	},
+	{
+		.c_id		= THERMAL_GENL_CMD_TZ_GET_TEMP,
+		.c_name		= (char *)"Get thermal zone temperature",
+		.c_msg_parser	= handle_netlink,
+		.c_maxattr	= THERMAL_GENL_ATTR_MAX,
+		.c_attr_policy	= thermal_genl_policy,
+	},
+	{
+		.c_id		= THERMAL_GENL_CMD_TZ_GET_TRIP,
+		.c_name		= (char *)"Get thermal zone trip points",
+		.c_msg_parser	= handle_netlink,
+		.c_maxattr	= THERMAL_GENL_ATTR_MAX,
+		.c_attr_policy	= thermal_genl_policy,
+	},
+	{
+		.c_id		= THERMAL_GENL_CMD_CDEV_GET,
+		.c_name		= (char *)"Get cooling devices",
+		.c_msg_parser	= handle_netlink,
+		.c_maxattr	= THERMAL_GENL_ATTR_MAX,
+		.c_attr_policy	= thermal_genl_policy,
+	},
+        {
+                .c_id           = THERMAL_GENL_CMD_THRESHOLD_GET,
+                .c_name         = (char *)"Get thresholds list",
+                .c_msg_parser   = handle_netlink,
+                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
+                .c_attr_policy  = thermal_genl_policy,
+        },
+        {
+                .c_id           = THERMAL_GENL_CMD_THRESHOLD_ADD,
+                .c_name         = (char *)"Add a threshold",
+                .c_msg_parser   = handle_netlink,
+                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
+                .c_attr_policy  = thermal_genl_policy,
+        },
+        {
+                .c_id           = THERMAL_GENL_CMD_THRESHOLD_DELETE,
+                .c_name         = (char *)"Delete a threshold",
+                .c_msg_parser   = handle_netlink,
+                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
+                .c_attr_policy  = thermal_genl_policy,
+        },
+        {
+                .c_id           = THERMAL_GENL_CMD_THRESHOLD_FLUSH,
+                .c_name         = (char *)"Flush the thresholds",
+                .c_msg_parser   = handle_netlink,
+                .c_maxattr      = THERMAL_GENL_ATTR_MAX,
+                .c_attr_policy  = thermal_genl_policy,
+        },
+};
+
+static struct genl_ops thermal_cmd_ops = {
+	.o_name		= (char *)"thermal",
+	.o_cmds		= thermal_cmds,
+	.o_ncmds	= ARRAY_SIZE(thermal_cmds),
+};
+
+struct cmd_param {
+	int tz_id;
+	int temp;
+	int direction;
+};
+
+typedef int (*cmd_cb_t)(struct nl_msg *, struct cmd_param *);
+
+static int thermal_genl_tz_id_encode(struct nl_msg *msg, struct cmd_param *p)
+{
+	if (nla_put_u32(msg, THERMAL_GENL_ATTR_TZ_ID, p->tz_id))
+		return -1;
+
+	return 0;
+}
+
+static int thermal_genl_threshold_encode(struct nl_msg *msg, struct cmd_param *p)
+{
+	if (thermal_genl_tz_id_encode(msg, p))
+		return -1;
+
+	if (nla_put_u32(msg, THERMAL_GENL_ATTR_THRESHOLD_TEMP, p->temp))
+		return -1;
+
+	if (nla_put_u32(msg, THERMAL_GENL_ATTR_THRESHOLD_DIRECTION, p->direction))
+		return -1;
+
+	return 0;
+}
+
+static thermal_error_t thermal_genl_auto(struct thermal_handler *th, cmd_cb_t cmd_cb,
+					 struct cmd_param *param,
+					 int cmd, int flags, void *arg)
+{
+	thermal_error_t ret = THERMAL_ERROR;
+	struct nl_msg *msg;
+	void *hdr;
+
+	msg = nlmsg_alloc();
+	if (!msg)
+		return THERMAL_ERROR;
+
+	hdr = genlmsg_put(msg, NL_AUTO_PORT, NL_AUTO_SEQ, thermal_cmd_ops.o_id,
+			  0, flags, cmd, THERMAL_GENL_VERSION);
+	if (!hdr)
+		goto out;
+
+	if (cmd_cb && cmd_cb(msg, param))
+		goto out;
+
+	if (nl_send_msg(th->sk_cmd, th->cb_cmd, msg, genl_handle_msg, arg))
+		goto out;
+
+	ret = THERMAL_SUCCESS;
+out:
+	nlmsg_free(msg);
+
+	return ret;
+}
+
+thermal_error_t thermal_cmd_get_tz(struct thermal_handler *th, struct thermal_zone **tz)
+{
+	return thermal_genl_auto(th, NULL, NULL, THERMAL_GENL_CMD_TZ_GET_ID,
+				 NLM_F_DUMP | NLM_F_ACK, tz);
+}
+
+thermal_error_t thermal_cmd_get_cdev(struct thermal_handler *th, struct thermal_cdev **tc)
+{
+	return thermal_genl_auto(th, NULL, NULL, THERMAL_GENL_CMD_CDEV_GET,
+				 NLM_F_DUMP | NLM_F_ACK, tc);
+}
+
+thermal_error_t thermal_cmd_get_trip(struct thermal_handler *th, struct thermal_zone *tz)
+{
+	struct cmd_param p = { .tz_id = tz->id };
+
+	return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
+				 THERMAL_GENL_CMD_TZ_GET_TRIP, 0, tz);
+}
+
+thermal_error_t thermal_cmd_get_governor(struct thermal_handler *th, struct thermal_zone *tz)
+{
+	struct cmd_param p = { .tz_id = tz->id };
+
+	return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
+				 THERMAL_GENL_CMD_TZ_GET_GOV, 0, tz);
+}
+
+thermal_error_t thermal_cmd_get_temp(struct thermal_handler *th, struct thermal_zone *tz)
+{
+	struct cmd_param p = { .tz_id = tz->id };
+
+	return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
+				 THERMAL_GENL_CMD_TZ_GET_TEMP, 0, tz);
+}
+
+thermal_error_t thermal_cmd_threshold_get(struct thermal_handler *th,
+                                          struct thermal_zone *tz)
+{
+	struct cmd_param p = { .tz_id = tz->id };
+
+        return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
+				 THERMAL_GENL_CMD_THRESHOLD_GET, 0, tz);
+}
+
+thermal_error_t thermal_cmd_threshold_add(struct thermal_handler *th,
+                                          struct thermal_zone *tz,
+                                          int temperature,
+                                          int direction)
+{
+	struct cmd_param p = { .tz_id = tz->id, .temp = temperature, .direction = direction };
+
+        return thermal_genl_auto(th, thermal_genl_threshold_encode, &p,
+				 THERMAL_GENL_CMD_THRESHOLD_ADD, 0, tz);
+}
+
+thermal_error_t thermal_cmd_threshold_delete(struct thermal_handler *th,
+                                             struct thermal_zone *tz,
+                                             int temperature,
+                                             int direction)
+{
+	struct cmd_param p = { .tz_id = tz->id, .temp = temperature, .direction = direction };
+
+        return thermal_genl_auto(th, thermal_genl_threshold_encode, &p,
+				 THERMAL_GENL_CMD_THRESHOLD_DELETE, 0, tz);
+}
+
+thermal_error_t thermal_cmd_threshold_flush(struct thermal_handler *th,
+                                            struct thermal_zone *tz)
+{
+	struct cmd_param p = { .tz_id = tz->id };
+
+        return thermal_genl_auto(th, thermal_genl_tz_id_encode, &p,
+				 THERMAL_GENL_CMD_THRESHOLD_FLUSH, 0, tz);
+}
+
+thermal_error_t thermal_cmd_exit(struct thermal_handler *th)
+{
+	if (genl_unregister_family(&thermal_cmd_ops))
+		return THERMAL_ERROR;
+
+	nl_thermal_disconnect(th->sk_cmd, th->cb_cmd);
+
+	return THERMAL_SUCCESS;
+}
+
+thermal_error_t thermal_cmd_init(struct thermal_handler *th)
+{
+	int ret;
+	int family;
+
+	if (nl_thermal_connect(&th->sk_cmd, &th->cb_cmd))
+		return THERMAL_ERROR;
+
+	ret = genl_register_family(&thermal_cmd_ops);
+	if (ret)
+		return THERMAL_ERROR;
+
+	ret = genl_ops_resolve(th->sk_cmd, &thermal_cmd_ops);
+	if (ret)
+		return THERMAL_ERROR;
+
+	family = genl_ctrl_resolve(th->sk_cmd, "nlctrl");
+	if (family != GENL_ID_CTRL)
+		return THERMAL_ERROR;
+
+	return THERMAL_SUCCESS;
+}
diff --git a/tools/lib/thermal/events.c b/tools/lib/thermal/events.c
new file mode 100644
index 000000000..bd851c869
--- /dev/null
+++ b/tools/lib/thermal/events.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: LGPL-2.1+
+// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
+#include <linux/netlink.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+
+#include <thermal.h>
+#include "thermal_nl.h"
+
+/*
+ * Optimization: fill this array to tell which event we do want to pay
+ * attention to. That happens at init time with the ops
+ * structure. Each ops will enable the event and the general handler
+ * will be able to discard the event if there is not ops associated
+ * with it.
+ */
+static int enabled_ops[__THERMAL_GENL_EVENT_MAX];
+
+static int handle_thermal_event(struct nl_msg *n, void *arg)
+{
+	struct nlmsghdr *nlh = nlmsg_hdr(n);
+	struct genlmsghdr *genlhdr = genlmsg_hdr(nlh);
+	struct nlattr *attrs[THERMAL_GENL_ATTR_MAX + 1];
+	struct thermal_handler_param *thp = arg;
+	struct thermal_events_ops *ops = &thp->th->ops->events;
+
+	genlmsg_parse(nlh, 0, attrs, THERMAL_GENL_ATTR_MAX, NULL);
+
+	arg = thp->arg;
+
+	/*
+	 * This is an event we don't care of, bail out.
+	 */
+	if (!enabled_ops[genlhdr->cmd])
+		return THERMAL_SUCCESS;
+
+	switch (genlhdr->cmd) {
+
+	case THERMAL_GENL_EVENT_TZ_CREATE:
+		return ops->tz_create(nla_get_string(attrs[THERMAL_GENL_ATTR_TZ_NAME]),
+				      nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_DELETE:
+		return ops->tz_delete(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_ENABLE:
+		return ops->tz_enable(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_DISABLE:
+		return ops->tz_disable(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_TRIP_CHANGE:
+		return ops->trip_change(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+					nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_ID]),
+					nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_TYPE]),
+					nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_TEMP]),
+					nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_HYST]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_TRIP_ADD:
+		return ops->trip_add(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_ID]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_TYPE]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_TEMP]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_HYST]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_TRIP_DELETE:
+		return ops->trip_delete(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+					nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_ID]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_TRIP_UP:
+		return ops->trip_high(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+				      nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_ID]),
+				      nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TEMP]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_TRIP_DOWN:
+		return ops->trip_low(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TRIP_ID]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TEMP]), arg);
+
+	case THERMAL_GENL_EVENT_CDEV_ADD:
+		return ops->cdev_add(nla_get_string(attrs[THERMAL_GENL_ATTR_CDEV_NAME]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_CDEV_ID]),
+				     nla_get_u32(attrs[THERMAL_GENL_ATTR_CDEV_MAX_STATE]), arg);
+
+	case THERMAL_GENL_EVENT_CDEV_DELETE:
+		return ops->cdev_delete(nla_get_u32(attrs[THERMAL_GENL_ATTR_CDEV_ID]), arg);
+
+	case THERMAL_GENL_EVENT_CDEV_STATE_UPDATE:
+		return ops->cdev_update(nla_get_u32(attrs[THERMAL_GENL_ATTR_CDEV_ID]),
+					nla_get_u32(attrs[THERMAL_GENL_ATTR_CDEV_CUR_STATE]), arg);
+
+	case THERMAL_GENL_EVENT_TZ_GOV_CHANGE:
+		return ops->gov_change(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+				       nla_get_string(attrs[THERMAL_GENL_ATTR_GOV_NAME]), arg);
+
+	case THERMAL_GENL_EVENT_THRESHOLD_ADD:
+		return ops->threshold_add(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+					  nla_get_u32(attrs[THERMAL_GENL_ATTR_THRESHOLD_TEMP]),
+					  nla_get_u32(attrs[THERMAL_GENL_ATTR_THRESHOLD_DIRECTION]), arg);
+
+	case THERMAL_GENL_EVENT_THRESHOLD_DELETE:
+		return ops->threshold_delete(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+					     nla_get_u32(attrs[THERMAL_GENL_ATTR_THRESHOLD_TEMP]),
+					     nla_get_u32(attrs[THERMAL_GENL_ATTR_THRESHOLD_DIRECTION]), arg);
+
+	case THERMAL_GENL_EVENT_THRESHOLD_FLUSH:
+		return ops->threshold_flush(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]), arg);
+
+	case THERMAL_GENL_EVENT_THRESHOLD_UP:
+		return ops->threshold_up(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+					 nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TEMP]),
+					 nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_PREV_TEMP]), arg);
+
+	case THERMAL_GENL_EVENT_THRESHOLD_DOWN:
+		return ops->threshold_down(nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+					   nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TEMP]),
+					   nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_PREV_TEMP]), arg);
+
+	default:
+		return -1;
+	}
+}
+
+static void thermal_events_ops_init(struct thermal_events_ops *ops)
+{
+	enabled_ops[THERMAL_GENL_EVENT_TZ_CREATE]		= !!ops->tz_create;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_DELETE]		= !!ops->tz_delete;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_DISABLE]		= !!ops->tz_disable;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_ENABLE]		= !!ops->tz_enable;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_TRIP_UP]		= !!ops->trip_high;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_TRIP_DOWN]		= !!ops->trip_low;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_TRIP_CHANGE]		= !!ops->trip_change;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_TRIP_ADD]		= !!ops->trip_add;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_TRIP_DELETE]		= !!ops->trip_delete;
+	enabled_ops[THERMAL_GENL_EVENT_CDEV_ADD]		= !!ops->cdev_add;
+	enabled_ops[THERMAL_GENL_EVENT_CDEV_DELETE]		= !!ops->cdev_delete;
+	enabled_ops[THERMAL_GENL_EVENT_CDEV_STATE_UPDATE] 	= !!ops->cdev_update;
+	enabled_ops[THERMAL_GENL_EVENT_TZ_GOV_CHANGE]		= !!ops->gov_change;
+	enabled_ops[THERMAL_GENL_EVENT_THRESHOLD_ADD]		= !!ops->threshold_add;
+	enabled_ops[THERMAL_GENL_EVENT_THRESHOLD_DELETE]	= !!ops->threshold_delete;
+	enabled_ops[THERMAL_GENL_EVENT_THRESHOLD_FLUSH]		= !!ops->threshold_flush;
+	enabled_ops[THERMAL_GENL_EVENT_THRESHOLD_UP]		= !!ops->threshold_up;
+	enabled_ops[THERMAL_GENL_EVENT_THRESHOLD_DOWN]		= !!ops->threshold_down;
+}
+
+thermal_error_t thermal_events_handle(struct thermal_handler *th, void *arg)
+{
+	struct thermal_handler_param thp = { .th = th, .arg = arg };
+
+	if (!th)
+		return THERMAL_ERROR;
+
+	if (nl_cb_set(th->cb_event, NL_CB_VALID, NL_CB_CUSTOM,
+		      handle_thermal_event, &thp))
+		return THERMAL_ERROR;
+
+	return nl_recvmsgs(th->sk_event, th->cb_event);
+}
+
+int thermal_events_fd(struct thermal_handler *th)
+{
+	if (!th)
+		return -1;
+
+	return nl_socket_get_fd(th->sk_event);
+}
+
+thermal_error_t thermal_events_exit(struct thermal_handler *th)
+{
+	if (nl_unsubscribe_thermal(th->sk_event, th->cb_event,
+				   THERMAL_GENL_EVENT_GROUP_NAME))
+		return THERMAL_ERROR;
+
+	nl_thermal_disconnect(th->sk_event, th->cb_event);
+
+	return THERMAL_SUCCESS;
+}
+
+thermal_error_t thermal_events_init(struct thermal_handler *th)
+{
+	thermal_events_ops_init(&th->ops->events);
+
+	if (nl_thermal_connect(&th->sk_event, &th->cb_event))
+		return THERMAL_ERROR;
+
+	if (nl_subscribe_thermal(th->sk_event, th->cb_event,
+				 THERMAL_GENL_EVENT_GROUP_NAME))
+		return THERMAL_ERROR;
+
+	return THERMAL_SUCCESS;
+}
diff --git a/tools/lib/thermal/include/thermal.h b/tools/lib/thermal/include/thermal.h
new file mode 100644
index 000000000..d9097271d
--- /dev/null
+++ b/tools/lib/thermal/include/thermal.h
@@ -0,0 +1,182 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+/* Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org> */
+#ifndef __LIBTHERMAL_H
+#define __LIBTHERMAL_H
+
+#include <linux/thermal.h>
+#include <sys/types.h>
+
+#ifndef LIBTHERMAL_API
+#define LIBTHERMAL_API __attribute__((visibility("default")))
+#endif
+
+#ifndef THERMAL_THRESHOLD_WAY_UP
+#define THERMAL_THRESHOLD_WAY_UP 0x1
+#endif
+
+#ifndef THERMAL_THRESHOLD_WAY_DOWN
+#define THERMAL_THRESHOLD_WAY_DOWN 0x2
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct thermal_sampling_ops {
+	int (*tz_temp)(int tz_id, int temp, void *arg);
+};
+
+struct thermal_events_ops {
+	int (*tz_create)(const char *name, int tz_id, void *arg);
+	int (*tz_delete)(int tz_id, void *arg);
+	int (*tz_enable)(int tz_id, void *arg);
+	int (*tz_disable)(int tz_id, void *arg);
+	int (*trip_high)(int tz_id, int trip_id, int temp, void *arg);
+	int (*trip_low)(int tz_id, int trip_id, int temp, void *arg);
+	int (*trip_add)(int tz_id, int trip_id, int type, int temp, int hyst, void *arg);
+	int (*trip_change)(int tz_id, int trip_id, int type, int temp, int hyst, void *arg);
+	int (*trip_delete)(int tz_id, int trip_id, void *arg);
+	int (*cdev_add)(const char *name, int cdev_id, int max_state, void *arg);
+	int (*cdev_delete)(int cdev_id, void *arg);
+	int (*cdev_update)(int cdev_id, int cur_state, void *arg);
+	int (*gov_change)(int tz_id, const char *gov_name, void *arg);
+	int (*threshold_add)(int tz_id, int temperature, int direction, void *arg);
+	int (*threshold_delete)(int tz_id, int temperature, int direction, void *arg);
+	int (*threshold_flush)(int tz_id, void *arg);
+	int (*threshold_up)(int tz_id, int temp, int prev_temp, void *arg);
+	int (*threshold_down)(int tz_id, int temp, int prev_temp, void *arg);
+};
+
+struct thermal_ops {
+	struct thermal_sampling_ops sampling;
+	struct thermal_events_ops events;
+};
+
+struct thermal_trip {
+	int id;
+	int type;
+	int temp;
+	int hyst;
+};
+
+struct thermal_threshold {
+	int temperature;
+	int direction;
+};
+
+struct thermal_zone {
+	int id;
+	int temp;
+	char name[THERMAL_NAME_LENGTH];
+	char governor[THERMAL_NAME_LENGTH];
+	struct thermal_trip *trip;
+	struct thermal_threshold *thresholds;
+};
+
+struct thermal_cdev {
+	int id;
+	char name[THERMAL_NAME_LENGTH];
+	int max_state;
+	int min_state;
+	int cur_state;
+};
+
+typedef enum {
+	THERMAL_ERROR = -1,
+	THERMAL_SUCCESS = 0,
+} thermal_error_t;
+
+struct thermal_handler;
+
+typedef int (*cb_tz_t)(struct thermal_zone *, void *);
+
+typedef int (*cb_tt_t)(struct thermal_trip *, void *);
+
+typedef int (*cb_tc_t)(struct thermal_cdev *, void *);
+
+typedef int (*cb_th_t)(struct thermal_threshold *, void *);
+
+LIBTHERMAL_API int for_each_thermal_zone(struct thermal_zone *tz, cb_tz_t cb, void *arg);
+
+LIBTHERMAL_API int for_each_thermal_trip(struct thermal_trip *tt, cb_tt_t cb, void *arg);
+
+LIBTHERMAL_API int for_each_thermal_cdev(struct thermal_cdev *cdev, cb_tc_t cb, void *arg);
+
+LIBTHERMAL_API int for_each_thermal_threshold(struct thermal_threshold *th, cb_th_t cb, void *arg);
+
+LIBTHERMAL_API struct thermal_zone *thermal_zone_find_by_name(struct thermal_zone *tz,
+							      const char *name);
+
+LIBTHERMAL_API struct thermal_zone *thermal_zone_find_by_id(struct thermal_zone *tz, int id);
+
+LIBTHERMAL_API struct thermal_zone *thermal_zone_discover(struct thermal_handler *th);
+
+LIBTHERMAL_API struct thermal_handler *thermal_init(struct thermal_ops *ops);
+
+LIBTHERMAL_API void thermal_exit(struct thermal_handler *th);
+
+/*
+ * Netlink thermal events
+ */
+LIBTHERMAL_API thermal_error_t thermal_events_exit(struct thermal_handler *th);
+
+LIBTHERMAL_API thermal_error_t thermal_events_init(struct thermal_handler *th);
+
+LIBTHERMAL_API thermal_error_t thermal_events_handle(struct thermal_handler *th, void *arg);
+
+LIBTHERMAL_API int thermal_events_fd(struct thermal_handler *th);
+
+/*
+ * Netlink thermal commands
+ */
+LIBTHERMAL_API thermal_error_t thermal_cmd_exit(struct thermal_handler *th);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_init(struct thermal_handler *th);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_get_tz(struct thermal_handler *th,
+						  struct thermal_zone **tz);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_get_cdev(struct thermal_handler *th,
+						    struct thermal_cdev **tc);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_get_trip(struct thermal_handler *th,
+						    struct thermal_zone *tz);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_get_governor(struct thermal_handler *th,
+							struct thermal_zone *tz);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_get_temp(struct thermal_handler *th,
+						    struct thermal_zone *tz);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_threshold_get(struct thermal_handler *th,
+							 struct thermal_zone *tz);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_threshold_add(struct thermal_handler *th,
+                                                         struct thermal_zone *tz,
+                                                         int temperature,
+                                                         int direction);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_threshold_delete(struct thermal_handler *th,
+                                                            struct thermal_zone *tz,
+                                                            int temperature,
+                                                            int direction);
+
+LIBTHERMAL_API thermal_error_t thermal_cmd_threshold_flush(struct thermal_handler *th,
+                                                           struct thermal_zone *tz);
+
+/*
+ * Netlink thermal samples
+ */
+LIBTHERMAL_API thermal_error_t thermal_sampling_exit(struct thermal_handler *th);
+
+LIBTHERMAL_API thermal_error_t thermal_sampling_init(struct thermal_handler *th);
+
+LIBTHERMAL_API thermal_error_t thermal_sampling_handle(struct thermal_handler *th, void *arg);
+
+LIBTHERMAL_API int thermal_sampling_fd(struct thermal_handler *th);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __LIBTHERMAL_H */
diff --git a/tools/lib/thermal/libthermal.map b/tools/lib/thermal/libthermal.map
new file mode 100644
index 000000000..1d3d0c04e
--- /dev/null
+++ b/tools/lib/thermal/libthermal.map
@@ -0,0 +1,33 @@
+LIBTHERMAL_0.0.1 {
+	global:
+		for_each_thermal_zone;
+		for_each_thermal_trip;
+		for_each_thermal_cdev;
+		for_each_thermal_threshold;
+		thermal_zone_find_by_name;
+		thermal_zone_find_by_id;
+		thermal_zone_discover;
+		thermal_init;
+		thermal_exit;
+		thermal_events_exit;
+		thermal_events_init;
+		thermal_events_handle;
+		thermal_events_fd;
+		thermal_cmd_exit;
+		thermal_cmd_init;
+		thermal_cmd_get_tz;
+		thermal_cmd_get_cdev;
+		thermal_cmd_get_trip;
+		thermal_cmd_get_governor;
+		thermal_cmd_get_temp;
+		thermal_cmd_threshold_get;
+		thermal_cmd_threshold_add;
+		thermal_cmd_threshold_delete;
+		thermal_cmd_threshold_flush;
+		thermal_sampling_exit;
+		thermal_sampling_init;
+		thermal_sampling_handle;
+		thermal_sampling_fd;
+local:
+		*;
+};
diff --git a/tools/lib/thermal/libthermal.pc.template b/tools/lib/thermal/libthermal.pc.template
new file mode 100644
index 000000000..3b8a24d0a
--- /dev/null
+++ b/tools/lib/thermal/libthermal.pc.template
@@ -0,0 +1,12 @@
+# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+prefix=@PREFIX@
+libdir=@LIBDIR@
+includedir=${prefix}/include
+
+Name: libthermal
+Description: thermal library
+Requires: libnl-3.0 libnl-genl-3.0
+Version: @VERSION@
+Libs: -L${libdir} -lnl-genl-3 -lnl-3 -lthermal
+Cflags: -I${includedir} -I${includedir}/libnl3
diff --git a/tools/lib/thermal/sampling.c b/tools/lib/thermal/sampling.c
new file mode 100644
index 000000000..f67c1f9ea
--- /dev/null
+++ b/tools/lib/thermal/sampling.c
@@ -0,0 +1,77 @@
+// SPDX-License-Identifier: LGPL-2.1+
+// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <thermal.h>
+#include "thermal_nl.h"
+
+static int handle_thermal_sample(struct nl_msg *n, void *arg)
+{
+	struct nlmsghdr *nlh = nlmsg_hdr(n);
+	struct genlmsghdr *genlhdr = genlmsg_hdr(nlh);
+	struct nlattr *attrs[THERMAL_GENL_ATTR_MAX + 1];
+	struct thermal_handler_param *thp = arg;
+	struct thermal_handler *th = thp->th;
+
+	arg = thp->arg;
+
+	genlmsg_parse(nlh, 0, attrs, THERMAL_GENL_ATTR_MAX, NULL);
+
+	switch (genlhdr->cmd) {
+
+	case THERMAL_GENL_SAMPLING_TEMP:
+		return th->ops->sampling.tz_temp(
+			nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_ID]),
+			nla_get_u32(attrs[THERMAL_GENL_ATTR_TZ_TEMP]), arg);
+	default:
+		return THERMAL_ERROR;
+	}
+}
+
+thermal_error_t thermal_sampling_handle(struct thermal_handler *th, void *arg)
+{
+	struct thermal_handler_param thp = { .th = th, .arg = arg };
+
+	if (!th)
+		return THERMAL_ERROR;
+
+	if (nl_cb_set(th->cb_sampling, NL_CB_VALID, NL_CB_CUSTOM,
+		      handle_thermal_sample, &thp))
+		return THERMAL_ERROR;
+
+	return nl_recvmsgs(th->sk_sampling, th->cb_sampling);
+}
+
+int thermal_sampling_fd(struct thermal_handler *th)
+{
+	if (!th)
+		return -1;
+
+	return nl_socket_get_fd(th->sk_sampling);
+}
+
+thermal_error_t thermal_sampling_exit(struct thermal_handler *th)
+{
+	if (nl_unsubscribe_thermal(th->sk_sampling, th->cb_sampling,
+				   THERMAL_GENL_SAMPLING_GROUP_NAME))
+		return THERMAL_ERROR;
+
+	nl_thermal_disconnect(th->sk_sampling, th->cb_sampling);
+
+	return THERMAL_SUCCESS;
+}
+
+thermal_error_t thermal_sampling_init(struct thermal_handler *th)
+{
+	if (nl_thermal_connect(&th->sk_sampling, &th->cb_sampling))
+		return THERMAL_ERROR;
+
+	if (nl_subscribe_thermal(th->sk_sampling, th->cb_sampling,
+				 THERMAL_GENL_SAMPLING_GROUP_NAME))
+		return THERMAL_ERROR;
+
+	return THERMAL_SUCCESS;
+}
diff --git a/tools/lib/thermal/thermal.c b/tools/lib/thermal/thermal.c
new file mode 100644
index 000000000..6f02e3539
--- /dev/null
+++ b/tools/lib/thermal/thermal.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: LGPL-2.1+
+// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
+#include <stdio.h>
+#include <limits.h>
+#include <thermal.h>
+
+#include "thermal_nl.h"
+
+int for_each_thermal_threshold(struct thermal_threshold *th, cb_th_t cb, void *arg)
+{
+	int i, ret = 0;
+
+	if (!th)
+		return 0;
+
+	for (i = 0; th[i].temperature != INT_MAX; i++)
+		ret |= cb(&th[i], arg);
+
+	return ret;
+}
+
+int for_each_thermal_cdev(struct thermal_cdev *cdev, cb_tc_t cb, void *arg)
+{
+	int i, ret = 0;
+
+	if (!cdev)
+		return 0;
+
+	for (i = 0; cdev[i].id != -1; i++)
+		ret |= cb(&cdev[i], arg);
+
+	return ret;
+}
+
+int for_each_thermal_trip(struct thermal_trip *tt, cb_tt_t cb, void *arg)
+{
+	int i, ret = 0;
+
+	if (!tt)
+		return 0;
+
+	for (i = 0; tt[i].id != -1; i++)
+		ret |= cb(&tt[i], arg);
+
+	return ret;
+}
+
+int for_each_thermal_zone(struct thermal_zone *tz, cb_tz_t cb, void *arg)
+{
+	int i, ret = 0;
+
+	if (!tz)
+		return 0;
+
+	for (i = 0; tz[i].id != -1; i++)
+		ret |= cb(&tz[i], arg);
+
+	return ret;
+}
+
+struct thermal_zone *thermal_zone_find_by_name(struct thermal_zone *tz,
+					       const char *name)
+{
+	int i;
+
+	if (!tz || !name)
+		return NULL;
+
+	for (i = 0; tz[i].id != -1; i++) {
+		if (!strcmp(tz[i].name, name))
+			return &tz[i];
+	}
+
+	return NULL;
+}
+
+struct thermal_zone *thermal_zone_find_by_id(struct thermal_zone *tz, int id)
+{
+	int i;
+
+	if (!tz || id < 0)
+		return NULL;
+
+	for (i = 0; tz[i].id != -1; i++) {
+		if (tz[i].id == id)
+			return &tz[i];
+	}
+
+	return NULL;
+}
+
+static int __thermal_zone_discover(struct thermal_zone *tz, void *th)
+{
+	if (thermal_cmd_get_trip(th, tz) < 0)
+		return -1;
+
+	if (thermal_cmd_threshold_get(th, tz))
+		return -1;
+
+	if (thermal_cmd_get_governor(th, tz))
+		return -1;
+
+	return 0;
+}
+
+struct thermal_zone *thermal_zone_discover(struct thermal_handler *th)
+{
+	struct thermal_zone *tz;
+
+	if (thermal_cmd_get_tz(th, &tz) < 0)
+		return NULL;
+
+	if (for_each_thermal_zone(tz, __thermal_zone_discover, th))
+		return NULL;
+
+	return tz;
+}
+
+void thermal_exit(struct thermal_handler *th)
+{
+	thermal_cmd_exit(th);
+	thermal_events_exit(th);
+	thermal_sampling_exit(th);
+
+	free(th);
+}
+
+struct thermal_handler *thermal_init(struct thermal_ops *ops)
+{
+	struct thermal_handler *th;
+
+	th = malloc(sizeof(*th));
+	if (!th)
+		return NULL;
+	th->ops = ops;
+
+	if (thermal_events_init(th))
+		goto out_free;
+
+	if (thermal_sampling_init(th))
+		goto out_free;
+
+	if (thermal_cmd_init(th))
+		goto out_free;
+
+	return th;
+
+out_free:
+	free(th);
+
+	return NULL;
+}
diff --git a/tools/lib/thermal/thermal_nl.c b/tools/lib/thermal/thermal_nl.c
new file mode 100644
index 000000000..b05cf9569
--- /dev/null
+++ b/tools/lib/thermal/thermal_nl.c
@@ -0,0 +1,215 @@
+// SPDX-License-Identifier: LGPL-2.1+
+// Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <thermal.h>
+#include "thermal_nl.h"
+
+struct handler_args {
+	const char *group;
+	int id;
+};
+
+static __thread int err;
+static __thread int done;
+
+static int nl_seq_check_handler(struct nl_msg *msg, void *arg)
+{
+	return NL_OK;
+}
+
+static int nl_error_handler(struct sockaddr_nl *nla, struct nlmsgerr *nl_err,
+			    void *arg)
+{
+	int *ret = arg;
+
+	if (ret)
+		*ret = nl_err->error;
+
+	return NL_STOP;
+}
+
+static int nl_finish_handler(struct nl_msg *msg, void *arg)
+{
+	int *ret = arg;
+
+	if (ret)
+		*ret = 1;
+
+	return NL_OK;
+}
+
+static int nl_ack_handler(struct nl_msg *msg, void *arg)
+{
+	int *ret = arg;
+
+	if (ret)
+		*ret = 1;
+
+	return NL_OK;
+}
+
+int nl_send_msg(struct nl_sock *sock, struct nl_cb *cb, struct nl_msg *msg,
+		int (*rx_handler)(struct nl_msg *, void *), void *data)
+{
+	if (!rx_handler)
+		return THERMAL_ERROR;
+
+	err = nl_send_auto_complete(sock, msg);
+	if (err < 0)
+		return err;
+
+	nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, rx_handler, data);
+
+	err = done = 0;
+
+	while (err == 0 && done == 0)
+		nl_recvmsgs(sock, cb);
+
+	return err;
+}
+
+static int nl_family_handler(struct nl_msg *msg, void *arg)
+{
+	struct handler_args *grp = arg;
+	struct nlattr *tb[CTRL_ATTR_MAX + 1];
+	struct genlmsghdr *gnlh = nlmsg_data(nlmsg_hdr(msg));
+	struct nlattr *mcgrp;
+	int rem_mcgrp;
+
+	nla_parse(tb, CTRL_ATTR_MAX, genlmsg_attrdata(gnlh, 0),
+		  genlmsg_attrlen(gnlh, 0), NULL);
+
+	if (!tb[CTRL_ATTR_MCAST_GROUPS])
+		return THERMAL_ERROR;
+
+	nla_for_each_nested(mcgrp, tb[CTRL_ATTR_MCAST_GROUPS], rem_mcgrp) {
+
+		struct nlattr *tb_mcgrp[CTRL_ATTR_MCAST_GRP_MAX + 1];
+
+		nla_parse(tb_mcgrp, CTRL_ATTR_MCAST_GRP_MAX,
+			  nla_data(mcgrp), nla_len(mcgrp), NULL);
+
+		if (!tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME] ||
+		    !tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID])
+			continue;
+
+		if (strncmp(nla_data(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME]),
+			    grp->group,
+			    nla_len(tb_mcgrp[CTRL_ATTR_MCAST_GRP_NAME])))
+			continue;
+
+		grp->id = nla_get_u32(tb_mcgrp[CTRL_ATTR_MCAST_GRP_ID]);
+
+		break;
+	}
+
+	return THERMAL_SUCCESS;
+}
+
+static int nl_get_multicast_id(struct nl_sock *sock, struct nl_cb *cb,
+			       const char *family, const char *group)
+{
+	struct nl_msg *msg;
+	int ret = 0, ctrlid;
+	struct handler_args grp = {
+		.group = group,
+		.id = -ENOENT,
+	};
+
+	msg = nlmsg_alloc();
+	if (!msg)
+		return THERMAL_ERROR;
+
+	ctrlid = genl_ctrl_resolve(sock, "nlctrl");
+
+	genlmsg_put(msg, 0, 0, ctrlid, 0, 0, CTRL_CMD_GETFAMILY, 0);
+
+	nla_put_string(msg, CTRL_ATTR_FAMILY_NAME, family);
+
+	ret = nl_send_msg(sock, cb, msg, nl_family_handler, &grp);
+	if (ret)
+		goto nla_put_failure;
+
+	ret = grp.id;
+
+nla_put_failure:
+	nlmsg_free(msg);
+	return ret;
+}
+
+int nl_thermal_connect(struct nl_sock **nl_sock, struct nl_cb **nl_cb)
+{
+	struct nl_cb *cb;
+	struct nl_sock *sock;
+
+	cb = nl_cb_alloc(NL_CB_DEFAULT);
+	if (!cb)
+		return THERMAL_ERROR;
+
+	sock = nl_socket_alloc();
+	if (!sock)
+		goto out_cb_free;
+
+	if (genl_connect(sock))
+		goto out_socket_free;
+
+	if (nl_cb_err(cb, NL_CB_CUSTOM, nl_error_handler, &err) ||
+	    nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, nl_finish_handler, &done) ||
+	    nl_cb_set(cb, NL_CB_ACK, NL_CB_CUSTOM, nl_ack_handler, &done) ||
+	    nl_cb_set(cb, NL_CB_SEQ_CHECK, NL_CB_CUSTOM, nl_seq_check_handler, &done))
+		return THERMAL_ERROR;
+
+	*nl_sock = sock;
+	*nl_cb = cb;
+
+	return THERMAL_SUCCESS;
+
+out_socket_free:
+	nl_socket_free(sock);
+out_cb_free:
+	nl_cb_put(cb);
+	return THERMAL_ERROR;
+}
+
+void nl_thermal_disconnect(struct nl_sock *nl_sock, struct nl_cb *nl_cb)
+{
+	nl_close(nl_sock);
+	nl_socket_free(nl_sock);
+	nl_cb_put(nl_cb);
+}
+
+int nl_unsubscribe_thermal(struct nl_sock *nl_sock, struct nl_cb *nl_cb,
+			   const char *group)
+{
+	int mcid;
+
+	mcid = nl_get_multicast_id(nl_sock, nl_cb, THERMAL_GENL_FAMILY_NAME,
+				   group);
+	if (mcid < 0)
+		return THERMAL_ERROR;
+
+	if (nl_socket_drop_membership(nl_sock, mcid))
+		return THERMAL_ERROR;
+
+	return THERMAL_SUCCESS;
+}
+
+int nl_subscribe_thermal(struct nl_sock *nl_sock, struct nl_cb *nl_cb,
+			 const char *group)
+{
+	int mcid;
+
+	mcid = nl_get_multicast_id(nl_sock, nl_cb, THERMAL_GENL_FAMILY_NAME,
+				   group);
+	if (mcid < 0)
+		return THERMAL_ERROR;
+
+	if (nl_socket_add_membership(nl_sock, mcid))
+		return THERMAL_ERROR;
+
+	return THERMAL_SUCCESS;
+}
diff --git a/tools/lib/thermal/thermal_nl.h b/tools/lib/thermal/thermal_nl.h
new file mode 100644
index 000000000..ddf635642
--- /dev/null
+++ b/tools/lib/thermal/thermal_nl.h
@@ -0,0 +1,46 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+/* Copyright (C) 2022, Linaro Ltd - Daniel Lezcano <daniel.lezcano@linaro.org> */
+#ifndef __THERMAL_H
+#define __THERMAL_H
+
+#include <netlink/netlink.h>
+#include <netlink/genl/genl.h>
+#include <netlink/genl/mngt.h>
+#include <netlink/genl/ctrl.h>
+
+struct thermal_handler {
+	int done;
+	int error;
+	struct thermal_ops *ops;
+	struct nl_msg *msg;
+	struct nl_sock *sk_event;
+	struct nl_sock *sk_sampling;
+	struct nl_sock *sk_cmd;
+	struct nl_cb *cb_cmd;
+	struct nl_cb *cb_event;
+	struct nl_cb *cb_sampling;
+};
+
+struct thermal_handler_param {
+	struct thermal_handler *th;
+	void *arg;
+};
+
+/*
+ * Low level netlink
+ */
+extern int nl_subscribe_thermal(struct nl_sock *nl_sock, struct nl_cb *nl_cb,
+				const char *group);
+
+extern int nl_unsubscribe_thermal(struct nl_sock *nl_sock, struct nl_cb *nl_cb,
+				  const char *group);
+
+extern int nl_thermal_connect(struct nl_sock **nl_sock, struct nl_cb **nl_cb);
+
+extern void nl_thermal_disconnect(struct nl_sock *nl_sock, struct nl_cb *nl_cb);
+
+extern int nl_send_msg(struct nl_sock *sock, struct nl_cb *nl_cb, struct nl_msg *msg,
+		       int (*rx_handler)(struct nl_msg *, void *),
+		       void *data);
+
+#endif /* __THERMAL_H */