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>

11 files changed, 3101 insertions, 0 deletions

diff --git a/tools/testing/selftests/alsa/.gitignore b/tools/testing/selftests/alsa/.gitignore
new file mode 100644
index 000000000..3dd8e1176
--- /dev/null
+++ b/tools/testing/selftests/alsa/.gitignore
@@ -0,0 +1,5 @@
+global-timer
+mixer-test
+pcm-test
+test-pcmtest-driver
+utimer-test
diff --git a/tools/testing/selftests/alsa/Makefile b/tools/testing/selftests/alsa/Makefile
new file mode 100644
index 000000000..8dab90ad2
--- /dev/null
+++ b/tools/testing/selftests/alsa/Makefile
@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+ifneq ($(shell pkg-config --exists alsa && echo 0 || echo 1),0)
+$(error Package alsa not found, please install alsa development package or \
+	add directory containing `alsa.pc` in PKG_CONFIG_PATH)
+endif
+
+CFLAGS += $(shell pkg-config --cflags alsa) $(KHDR_INCLUDES)
+LDLIBS += $(shell pkg-config --libs alsa)
+ifeq ($(LDLIBS),)
+LDLIBS += -lasound
+endif
+CFLAGS += -L$(OUTPUT) -Wl,-rpath=./
+
+LDLIBS+=-lpthread
+
+OVERRIDE_TARGETS = 1
+
+TEST_GEN_PROGS := mixer-test pcm-test test-pcmtest-driver utimer-test
+
+TEST_GEN_PROGS_EXTENDED := libatest.so global-timer
+
+TEST_FILES := conf.d pcm-test.conf
+
+include ../lib.mk
+
+$(OUTPUT)/libatest.so: conf.c alsa-local.h
+	$(CC) $(CFLAGS) -shared -fPIC $< $(LDLIBS) -o $@
+
+$(OUTPUT)/%: %.c $(OUTPUT)/libatest.so alsa-local.h
+	$(CC) $(CFLAGS) $< $(LDLIBS) -latest -o $@
diff --git a/tools/testing/selftests/alsa/alsa-local.h b/tools/testing/selftests/alsa/alsa-local.h
new file mode 100644
index 000000000..29143ef52
--- /dev/null
+++ b/tools/testing/selftests/alsa/alsa-local.h
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// kselftest configuration helpers for the hw specific configuration
+//
+// Original author: Jaroslav Kysela <perex@perex.cz>
+// Copyright (c) 2022 Red Hat Inc.
+
+#ifndef __ALSA_LOCAL_H
+#define __ALSA_LOCAL_H
+
+#include <alsa/asoundlib.h>
+
+snd_config_t *get_alsalib_config(void);
+
+snd_config_t *conf_load_from_file(const char *filename);
+void conf_load(void);
+void conf_free(void);
+snd_config_t *conf_by_card(int card);
+snd_config_t *conf_get_subtree(snd_config_t *root, const char *key1, const char *key2);
+int conf_get_count(snd_config_t *root, const char *key1, const char *key2);
+const char *conf_get_string(snd_config_t *root, const char *key1, const char *key2, const char *def);
+long conf_get_long(snd_config_t *root, const char *key1, const char *key2, long def);
+int conf_get_bool(snd_config_t *root, const char *key1, const char *key2, int def);
+void conf_get_string_array(snd_config_t *root, const char *key1, const char *key2,
+			   const char **array, int array_size, const char *def);
+
+struct card_cfg_data {
+	int card;
+	snd_config_t *config;
+	const char *filename;
+	const char *config_id;
+	struct card_cfg_data *next;
+};
+
+extern struct card_cfg_data *conf_cards;
+
+#endif /* __ALSA_LOCAL_H */
diff --git a/tools/testing/selftests/alsa/conf.c b/tools/testing/selftests/alsa/conf.c
new file mode 100644
index 000000000..317212078
--- /dev/null
+++ b/tools/testing/selftests/alsa/conf.c
@@ -0,0 +1,475 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// kselftest configuration helpers for the hw specific configuration
+//
+// Original author: Jaroslav Kysela <perex@perex.cz>
+// Copyright (c) 2022 Red Hat Inc.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <assert.h>
+#include <dirent.h>
+#include <regex.h>
+#include <sys/stat.h>
+
+#include "kselftest.h"
+#include "alsa-local.h"
+
+#define SYSFS_ROOT "/sys"
+
+struct card_cfg_data *conf_cards;
+
+static const char *alsa_config =
+"ctl.hw {\n"
+"	@args [ CARD ]\n"
+"	@args.CARD.type string\n"
+"	type hw\n"
+"	card $CARD\n"
+"}\n"
+"pcm.hw {\n"
+"	@args [ CARD DEV SUBDEV ]\n"
+"	@args.CARD.type string\n"
+"	@args.DEV.type integer\n"
+"	@args.SUBDEV.type integer\n"
+"	type hw\n"
+"	card $CARD\n"
+"	device $DEV\n"
+"	subdevice $SUBDEV\n"
+"}\n"
+;
+
+#ifdef SND_LIB_VER
+#if SND_LIB_VERSION >= SND_LIB_VER(1, 2, 6)
+#define LIB_HAS_LOAD_STRING
+#endif
+#endif
+
+#ifndef LIB_HAS_LOAD_STRING
+static int snd_config_load_string(snd_config_t **config, const char *s,
+				  size_t size)
+{
+	snd_input_t *input;
+	snd_config_t *dst;
+	int err;
+
+	assert(config && s);
+	if (size == 0)
+		size = strlen(s);
+	err = snd_input_buffer_open(&input, s, size);
+	if (err < 0)
+		return err;
+	err = snd_config_top(&dst);
+	if (err < 0) {
+		snd_input_close(input);
+		return err;
+	}
+	err = snd_config_load(dst, input);
+	snd_input_close(input);
+	if (err < 0) {
+		snd_config_delete(dst);
+		return err;
+	}
+	*config = dst;
+	return 0;
+}
+#endif
+
+snd_config_t *get_alsalib_config(void)
+{
+	snd_config_t *config;
+	int err;
+
+	err = snd_config_load_string(&config, alsa_config, strlen(alsa_config));
+	if (err < 0) {
+		ksft_print_msg("Unable to parse custom alsa-lib configuration: %s\n",
+			       snd_strerror(err));
+		ksft_exit_fail();
+	}
+	return config;
+}
+
+static struct card_cfg_data *conf_data_by_card(int card, bool msg)
+{
+	struct card_cfg_data *conf;
+
+	for (conf = conf_cards; conf; conf = conf->next) {
+		if (conf->card == card) {
+			if (msg)
+				ksft_print_msg("using hw card config %s for card %d\n",
+					       conf->filename, card);
+			return conf;
+		}
+	}
+	return NULL;
+}
+
+static void dump_config_tree(snd_config_t *top)
+{
+	snd_output_t *out;
+	int err;
+
+	err = snd_output_stdio_attach(&out, stdout, 0);
+	if (err < 0)
+		ksft_exit_fail_msg("stdout attach\n");
+	if (snd_config_save(top, out))
+		ksft_exit_fail_msg("config save\n");
+	snd_output_close(out);
+}
+
+snd_config_t *conf_load_from_file(const char *filename)
+{
+	snd_config_t *dst;
+	snd_input_t *input;
+	int err;
+
+	err = snd_input_stdio_open(&input, filename, "r");
+	if (err < 0)
+		ksft_exit_fail_msg("Unable to parse filename %s\n", filename);
+	err = snd_config_top(&dst);
+	if (err < 0)
+		ksft_exit_fail_msg("Out of memory\n");
+	err = snd_config_load(dst, input);
+	snd_input_close(input);
+	if (err < 0)
+		ksft_exit_fail_msg("Unable to parse filename %s\n", filename);
+	return dst;
+}
+
+static char *sysfs_get(const char *sysfs_root, const char *id)
+{
+	char path[PATH_MAX], link[PATH_MAX + 1];
+	struct stat sb;
+	ssize_t len;
+	char *e;
+	int fd;
+
+	if (id[0] == '/')
+		id++;
+	snprintf(path, sizeof(path), "%s/%s", sysfs_root, id);
+	if (lstat(path, &sb) != 0)
+		return NULL;
+	if (S_ISLNK(sb.st_mode)) {
+		len = readlink(path, link, sizeof(link) - 1);
+		if (len <= 0) {
+			ksft_exit_fail_msg("sysfs: cannot read link '%s': %s\n",
+					   path, strerror(errno));
+			return NULL;
+		}
+		link[len] = '\0';
+		e = strrchr(link, '/');
+		if (e)
+			return strdup(e + 1);
+		return NULL;
+	}
+	if (S_ISDIR(sb.st_mode))
+		return NULL;
+	if ((sb.st_mode & S_IRUSR) == 0)
+		return NULL;
+
+	fd = open(path, O_RDONLY);
+	if (fd < 0) {
+		if (errno == ENOENT)
+			return NULL;
+		ksft_exit_fail_msg("sysfs: open failed for '%s': %s\n",
+				   path, strerror(errno));
+	}
+	len = read(fd, path, sizeof(path)-1);
+	close(fd);
+	if (len < 0)
+		ksft_exit_fail_msg("sysfs: unable to read value '%s': %s\n",
+				   path, strerror(errno));
+	while (len > 0 && path[len-1] == '\n')
+		len--;
+	path[len] = '\0';
+	e = strdup(path);
+	if (e == NULL)
+		ksft_exit_fail_msg("Out of memory\n");
+	return e;
+}
+
+static bool sysfs_match(const char *sysfs_root, snd_config_t *config)
+{
+	snd_config_t *node, *path_config, *regex_config;
+	snd_config_iterator_t i, next;
+	const char *path_string, *regex_string, *v;
+	regex_t re;
+	regmatch_t match[1];
+	int iter = 0, ret;
+
+	snd_config_for_each(i, next, config) {
+		node = snd_config_iterator_entry(i);
+		if (snd_config_search(node, "path", &path_config))
+			ksft_exit_fail_msg("Missing path field in the sysfs block\n");
+		if (snd_config_search(node, "regex", &regex_config))
+			ksft_exit_fail_msg("Missing regex field in the sysfs block\n");
+		if (snd_config_get_string(path_config, &path_string))
+			ksft_exit_fail_msg("Path field in the sysfs block is not a string\n");
+		if (snd_config_get_string(regex_config, &regex_string))
+			ksft_exit_fail_msg("Regex field in the sysfs block is not a string\n");
+		iter++;
+		v = sysfs_get(sysfs_root, path_string);
+		if (!v)
+			return false;
+		if (regcomp(&re, regex_string, REG_EXTENDED))
+			ksft_exit_fail_msg("Wrong regex '%s'\n", regex_string);
+		ret = regexec(&re, v, 1, match, 0);
+		regfree(&re);
+		if (ret)
+			return false;
+	}
+	return iter > 0;
+}
+
+static void assign_card_config(int card, const char *sysfs_card_root)
+{
+	struct card_cfg_data *data;
+	snd_config_t *sysfs_card_config;
+
+	for (data = conf_cards; data; data = data->next) {
+		snd_config_search(data->config, "sysfs", &sysfs_card_config);
+		if (!sysfs_match(sysfs_card_root, sysfs_card_config))
+			continue;
+
+		data->card = card;
+		break;
+	}
+}
+
+static void assign_card_configs(void)
+{
+	char fn[128];
+	int card;
+
+	for (card = 0; card < 32; card++) {
+		snprintf(fn, sizeof(fn), "%s/class/sound/card%d", SYSFS_ROOT, card);
+		if (access(fn, R_OK) == 0)
+			assign_card_config(card, fn);
+	}
+}
+
+static int filename_filter(const struct dirent *dirent)
+{
+	size_t flen;
+
+	if (dirent == NULL)
+		return 0;
+	if (dirent->d_type == DT_DIR)
+		return 0;
+	flen = strlen(dirent->d_name);
+	if (flen <= 5)
+		return 0;
+	if (strncmp(&dirent->d_name[flen-5], ".conf", 5) == 0)
+		return 1;
+	return 0;
+}
+
+static bool match_config(const char *filename)
+{
+	struct card_cfg_data *data;
+	snd_config_t *config, *sysfs_config, *card_config, *sysfs_card_config, *node;
+	snd_config_iterator_t i, next;
+
+	config = conf_load_from_file(filename);
+	if (snd_config_search(config, "sysfs", &sysfs_config) ||
+	    snd_config_get_type(sysfs_config) != SND_CONFIG_TYPE_COMPOUND)
+		ksft_exit_fail_msg("Missing global sysfs block in filename %s\n", filename);
+	if (snd_config_search(config, "card", &card_config) ||
+	    snd_config_get_type(card_config) != SND_CONFIG_TYPE_COMPOUND)
+		ksft_exit_fail_msg("Missing global card block in filename %s\n", filename);
+	if (!sysfs_match(SYSFS_ROOT, sysfs_config))
+		return false;
+	snd_config_for_each(i, next, card_config) {
+		node = snd_config_iterator_entry(i);
+		if (snd_config_search(node, "sysfs", &sysfs_card_config) ||
+		    snd_config_get_type(sysfs_card_config) != SND_CONFIG_TYPE_COMPOUND)
+			ksft_exit_fail_msg("Missing card sysfs block in filename %s\n", filename);
+
+		data = malloc(sizeof(*data));
+		if (!data)
+			ksft_exit_fail_msg("Out of memory\n");
+		data->filename = filename;
+		data->config = node;
+		data->card = -1;
+		if (snd_config_get_id(node, &data->config_id))
+			ksft_exit_fail_msg("snd_config_get_id failed for card\n");
+		data->next = conf_cards;
+		conf_cards = data;
+	}
+	return true;
+}
+
+void conf_load(void)
+{
+	const char *fn = "conf.d";
+	struct dirent **namelist;
+	int n, j;
+
+	n = scandir(fn, &namelist, filename_filter, alphasort);
+	if (n < 0)
+		ksft_exit_fail_msg("scandir: %s\n", strerror(errno));
+	for (j = 0; j < n; j++) {
+		size_t sl = strlen(fn) + strlen(namelist[j]->d_name) + 2;
+		char *filename = malloc(sl);
+		if (filename == NULL)
+			ksft_exit_fail_msg("Out of memory\n");
+		sprintf(filename, "%s/%s", fn, namelist[j]->d_name);
+		if (match_config(filename))
+			filename = NULL;
+		free(filename);
+		free(namelist[j]);
+	}
+	free(namelist);
+
+	assign_card_configs();
+}
+
+void conf_free(void)
+{
+	struct card_cfg_data *conf;
+
+	while (conf_cards) {
+		conf = conf_cards;
+		conf_cards = conf->next;
+		snd_config_delete(conf->config);
+	}
+}
+
+snd_config_t *conf_by_card(int card)
+{
+	struct card_cfg_data *conf;
+
+	conf = conf_data_by_card(card, true);
+	if (conf)
+		return conf->config;
+	return NULL;
+}
+
+static int conf_get_by_keys(snd_config_t *root, const char *key1,
+			    const char *key2, snd_config_t **result)
+{
+	int ret;
+
+	if (key1) {
+		ret = snd_config_search(root, key1, &root);
+		if (ret != -ENOENT && ret < 0)
+			return ret;
+	}
+	if (key2)
+		ret = snd_config_search(root, key2, &root);
+	if (ret >= 0)
+		*result = root;
+	return ret;
+}
+
+snd_config_t *conf_get_subtree(snd_config_t *root, const char *key1, const char *key2)
+{
+	int ret;
+
+	if (!root)
+		return NULL;
+	ret = conf_get_by_keys(root, key1, key2, &root);
+	if (ret == -ENOENT)
+		return NULL;
+	if (ret < 0)
+		ksft_exit_fail_msg("key '%s'.'%s' search error: %s\n", key1, key2, snd_strerror(ret));
+	return root;
+}
+
+int conf_get_count(snd_config_t *root, const char *key1, const char *key2)
+{
+	snd_config_t *cfg;
+	snd_config_iterator_t i, next;
+	int count, ret;
+
+	if (!root)
+		return -1;
+	ret = conf_get_by_keys(root, key1, key2, &cfg);
+	if (ret == -ENOENT)
+		return -1;
+	if (ret < 0)
+		ksft_exit_fail_msg("key '%s'.'%s' search error: %s\n", key1, key2, snd_strerror(ret));
+	if (snd_config_get_type(cfg) != SND_CONFIG_TYPE_COMPOUND)
+		ksft_exit_fail_msg("key '%s'.'%s' is not a compound\n", key1, key2);
+	count = 0;
+	snd_config_for_each(i, next, cfg)
+		count++;
+	return count;
+}
+
+const char *conf_get_string(snd_config_t *root, const char *key1, const char *key2, const char *def)
+{
+	snd_config_t *cfg;
+	const char *s;
+	int ret;
+
+	if (!root)
+		return def;
+	ret = conf_get_by_keys(root, key1, key2, &cfg);
+	if (ret == -ENOENT)
+		return def;
+	if (ret < 0)
+		ksft_exit_fail_msg("key '%s'.'%s' search error: %s\n", key1, key2, snd_strerror(ret));
+	if (snd_config_get_string(cfg, &s))
+		ksft_exit_fail_msg("key '%s'.'%s' is not a string\n", key1, key2);
+	return s;
+}
+
+long conf_get_long(snd_config_t *root, const char *key1, const char *key2, long def)
+{
+	snd_config_t *cfg;
+	long l;
+	int ret;
+
+	if (!root)
+		return def;
+	ret = conf_get_by_keys(root, key1, key2, &cfg);
+	if (ret == -ENOENT)
+		return def;
+	if (ret < 0)
+		ksft_exit_fail_msg("key '%s'.'%s' search error: %s\n", key1, key2, snd_strerror(ret));
+	if (snd_config_get_integer(cfg, &l))
+		ksft_exit_fail_msg("key '%s'.'%s' is not an integer\n", key1, key2);
+	return l;
+}
+
+int conf_get_bool(snd_config_t *root, const char *key1, const char *key2, int def)
+{
+	snd_config_t *cfg;
+	int ret;
+
+	if (!root)
+		return def;
+	ret = conf_get_by_keys(root, key1, key2, &cfg);
+	if (ret == -ENOENT)
+		return def;
+	if (ret < 0)
+		ksft_exit_fail_msg("key '%s'.'%s' search error: %s\n", key1, key2, snd_strerror(ret));
+	ret = snd_config_get_bool(cfg);
+	if (ret < 0)
+		ksft_exit_fail_msg("key '%s'.'%s' is not a bool\n", key1, key2);
+	return !!ret;
+}
+
+void conf_get_string_array(snd_config_t *root, const char *key1, const char *key2,
+			   const char **array, int array_size, const char *def)
+{
+	snd_config_t *cfg;
+	char buf[16];
+	int ret, index;
+
+	ret = conf_get_by_keys(root, key1, key2, &cfg);
+	if (ret == -ENOENT)
+		cfg = NULL;
+	else if (ret < 0)
+		ksft_exit_fail_msg("key '%s'.'%s' search error: %s\n", key1, key2, snd_strerror(ret));
+	for (index = 0; index < array_size; index++) {
+		if (cfg == NULL) {
+			array[index] = def;
+		} else {
+			sprintf(buf, "%i", index);
+			array[index] = conf_get_string(cfg, buf, NULL, def);
+		}
+	}
+}
diff --git a/tools/testing/selftests/alsa/conf.d/Lenovo_ThinkPad_P1_Gen2.conf b/tools/testing/selftests/alsa/conf.d/Lenovo_ThinkPad_P1_Gen2.conf
new file mode 100644
index 000000000..5b40a9162
--- /dev/null
+++ b/tools/testing/selftests/alsa/conf.d/Lenovo_ThinkPad_P1_Gen2.conf
@@ -0,0 +1,84 @@
+#
+# Example configuration for Lenovo ThinkPad P1 Gen2
+#
+
+#
+# Use regex match for the string read from the given sysfs path
+#
+# The sysfs root directory (/sys) is hardwired in the test code
+# (may be changed on demand).
+#
+# All strings must match.
+#
+sysfs [
+	{
+		path "class/dmi/id/product_sku"
+		regex "LENOVO_MT_20QU_BU_Think_FM_ThinkPad P1 Gen 2"
+	}
+]
+
+card.hda {
+	#
+	# Use regex match for the /sys/class/sound/card*/ tree (relative)
+	#
+	sysfs [
+		{
+			path "device/subsystem_device"
+			regex "0x229e"
+		}
+		{
+			path "device/subsystem_vendor"
+			regex "0x17aa"
+		}
+	]
+
+	#
+	# PCM configuration
+	#
+	# pcm.0.0 - device 0 subdevice 0
+	#
+	pcm.0.0 {
+		PLAYBACK {
+			test.time1 {
+				access RW_INTERLEAVED	# can be omitted - default
+				format S16_LE		# can be omitted - default
+				rate 48000		# can be omitted - default
+				channels 2		# can be omitted - default
+				period_size 512
+				buffer_size 4096
+			}
+			test.time2 {
+				access RW_INTERLEAVED
+				format S16_LE
+				rate 48000
+				channels 2
+				period_size 24000
+				buffer_size 192000
+			}
+			test.time3 {
+				access RW_INTERLEAVED
+				format S16_LE
+				rate 44100
+				channels 2
+				period_size 24000
+				buffer_size 192000
+			}
+		}
+		CAPTURE {
+			# use default tests, check for the presence
+		}
+	}
+	#
+	# uncomment to force the missing device checks
+	#
+	#pcm.0.2 {
+	#	PLAYBACK {
+	#		# check for the presence
+	#	}
+	#}
+	#pcm.0.3 {
+	#	CAPTURE {
+	#		# check for the presence
+	#	}
+	#}
+}
diff --git a/tools/testing/selftests/alsa/global-timer.c b/tools/testing/selftests/alsa/global-timer.c
new file mode 100644
index 000000000..c15ec0ba8
--- /dev/null
+++ b/tools/testing/selftests/alsa/global-timer.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This tool is used by the utimer test, and it allows us to
+ * count the ticks of a global timer in a certain time frame
+ * (which is set by `timeout` parameter).
+ *
+ * Author: Ivan Orlov <ivan.orlov0322@gmail.com>
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <alsa/asoundlib.h>
+#include <time.h>
+
+static int ticked;
+static void async_callback(snd_async_handler_t *ahandler)
+{
+	ticked++;
+}
+
+static char timer_name[64];
+static void bind_to_timer(int device, int subdevice, int timeout)
+{
+	snd_timer_t *handle;
+	snd_timer_params_t *params;
+	snd_async_handler_t *ahandler;
+
+	time_t end;
+
+	sprintf(timer_name, "hw:CLASS=%d,SCLASS=%d,DEV=%d,SUBDEV=%d",
+		SND_TIMER_CLASS_GLOBAL, SND_TIMER_SCLASS_NONE,
+		device, subdevice);
+
+	snd_timer_params_alloca(&params);
+
+	if (snd_timer_open(&handle, timer_name, SND_TIMER_OPEN_NONBLOCK) < 0) {
+		perror("Can't open the timer");
+		exit(EXIT_FAILURE);
+	}
+
+	snd_timer_params_set_auto_start(params, 1);
+	snd_timer_params_set_ticks(params, 1);
+	if (snd_timer_params(handle, params) < 0) {
+		perror("Can't set timer params");
+		exit(EXIT_FAILURE);
+	}
+
+	if (snd_async_add_timer_handler(&ahandler, handle, async_callback, NULL) < 0) {
+		perror("Can't create a handler");
+		exit(EXIT_FAILURE);
+	}
+	end = time(NULL) + timeout;
+	if (snd_timer_start(handle) < 0) {
+		perror("Failed to start the timer");
+		exit(EXIT_FAILURE);
+	}
+	printf("Timer has started\n");
+	while (time(NULL) <= end) {
+		/*
+		 * Waiting for the timeout to elapse. Can't use sleep here, as it gets
+		 * constantly interrupted by the signal from the timer (SIGIO)
+		 */
+	}
+	snd_timer_stop(handle);
+	snd_timer_close(handle);
+}
+
+int main(int argc, char *argv[])
+{
+	int device, subdevice, timeout;
+
+	if (argc < 4) {
+		perror("Usage: %s <device> <subdevice> <timeout>");
+		return EXIT_FAILURE;
+	}
+
+	setlinebuf(stdout);
+
+	device = atoi(argv[1]);
+	subdevice = atoi(argv[2]);
+	timeout = atoi(argv[3]);
+
+	bind_to_timer(device, subdevice, timeout);
+
+	printf("Total ticks count: %d\n", ticked);
+
+	return EXIT_SUCCESS;
+}
diff --git a/tools/testing/selftests/alsa/mixer-test.c b/tools/testing/selftests/alsa/mixer-test.c
new file mode 100644
index 000000000..a329f901c
--- /dev/null
+++ b/tools/testing/selftests/alsa/mixer-test.c
@@ -0,0 +1,1146 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// kselftest for the ALSA mixer API
+//
+// Original author: Mark Brown <broonie@kernel.org>
+// Copyright (c) 2021-2 Arm Limited
+
+// This test will iterate over all cards detected in the system, exercising
+// every mixer control it can find.  This may conflict with other system
+// software if there is audio activity so is best run on a system with a
+// minimal active userspace.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <limits.h>
+#include <string.h>
+#include <getopt.h>
+#include <stdarg.h>
+#include <ctype.h>
+#include <math.h>
+#include <errno.h>
+#include <assert.h>
+#include <alsa/asoundlib.h>
+#include <poll.h>
+#include <stdint.h>
+
+#include "kselftest.h"
+#include "alsa-local.h"
+
+#define TESTS_PER_CONTROL 7
+
+struct card_data {
+	snd_ctl_t *handle;
+	int card;
+	snd_ctl_card_info_t *info;
+	const char *card_name;
+	struct pollfd pollfd;
+	int num_ctls;
+	snd_ctl_elem_list_t *ctls;
+	struct card_data *next;
+};
+
+struct ctl_data {
+	const char *name;
+	snd_ctl_elem_id_t *id;
+	snd_ctl_elem_info_t *info;
+	snd_ctl_elem_value_t *def_val;
+	int elem;
+	int event_missing;
+	int event_spurious;
+	struct card_data *card;
+	struct ctl_data *next;
+};
+
+int num_cards;
+int num_controls;
+struct card_data *card_list;
+struct ctl_data *ctl_list;
+
+static void find_controls(void)
+{
+	char name[32];
+	int card, ctl, err;
+	struct card_data *card_data;
+	struct ctl_data *ctl_data;
+	snd_config_t *config;
+	char *card_name, *card_longname;
+
+	card = -1;
+	if (snd_card_next(&card) < 0 || card < 0)
+		return;
+
+	config = get_alsalib_config();
+
+	while (card >= 0) {
+		sprintf(name, "hw:%d", card);
+
+		card_data = malloc(sizeof(*card_data));
+		if (!card_data)
+			ksft_exit_fail_msg("Out of memory\n");
+
+		err = snd_ctl_open_lconf(&card_data->handle, name, 0, config);
+		if (err < 0) {
+			ksft_print_msg("Failed to get hctl for card %d: %s\n",
+				       card, snd_strerror(err));
+			free(card_data);
+			goto next_card;
+		}
+
+		err = snd_card_get_name(card, &card_name);
+		if (err != 0)
+			card_name = "Unknown";
+		err = snd_card_get_longname(card, &card_longname);
+		if (err != 0)
+			card_longname = "Unknown";
+
+		err = snd_ctl_card_info_malloc(&card_data->info);
+		if (err != 0)
+			ksft_exit_fail_msg("Failed to allocate card info: %d\n",
+				err);
+
+		err = snd_ctl_card_info(card_data->handle, card_data->info);
+		if (err == 0) {
+			card_data->card_name = snd_ctl_card_info_get_id(card_data->info);
+			if (!card_data->card_name)
+				ksft_print_msg("Failed to get card ID\n");
+		} else {
+			ksft_print_msg("Failed to get card info: %d\n", err);
+		}
+
+		if (!card_data->card_name)
+			card_data->card_name = "Unknown";
+
+		ksft_print_msg("Card %d/%s - %s (%s)\n", card,
+			       card_data->card_name, card_name, card_longname);
+
+		/* Count controls */
+		snd_ctl_elem_list_malloc(&card_data->ctls);
+		snd_ctl_elem_list(card_data->handle, card_data->ctls);
+		card_data->num_ctls = snd_ctl_elem_list_get_count(card_data->ctls);
+
+		/* Enumerate control information */
+		snd_ctl_elem_list_alloc_space(card_data->ctls, card_data->num_ctls);
+		snd_ctl_elem_list(card_data->handle, card_data->ctls);
+
+		card_data->card = num_cards++;
+		card_data->next = card_list;
+		card_list = card_data;
+
+		num_controls += card_data->num_ctls;
+
+		for (ctl = 0; ctl < card_data->num_ctls; ctl++) {
+			ctl_data = malloc(sizeof(*ctl_data));
+			if (!ctl_data)
+				ksft_exit_fail_msg("Out of memory\n");
+
+			memset(ctl_data, 0, sizeof(*ctl_data));
+			ctl_data->card = card_data;
+			ctl_data->elem = ctl;
+			ctl_data->name = snd_ctl_elem_list_get_name(card_data->ctls,
+								    ctl);
+
+			err = snd_ctl_elem_id_malloc(&ctl_data->id);
+			if (err < 0)
+				ksft_exit_fail_msg("Out of memory\n");
+
+			err = snd_ctl_elem_info_malloc(&ctl_data->info);
+			if (err < 0)
+				ksft_exit_fail_msg("Out of memory\n");
+
+			err = snd_ctl_elem_value_malloc(&ctl_data->def_val);
+			if (err < 0)
+				ksft_exit_fail_msg("Out of memory\n");
+
+			snd_ctl_elem_list_get_id(card_data->ctls, ctl,
+						 ctl_data->id);
+			snd_ctl_elem_info_set_id(ctl_data->info, ctl_data->id);
+			err = snd_ctl_elem_info(card_data->handle,
+						ctl_data->info);
+			if (err < 0) {
+				ksft_print_msg("%s getting info for %s\n",
+					       snd_strerror(err),
+					       ctl_data->name);
+			}
+
+			snd_ctl_elem_value_set_id(ctl_data->def_val,
+						  ctl_data->id);
+
+			ctl_data->next = ctl_list;
+			ctl_list = ctl_data;
+		}
+
+		/* Set up for events */
+		err = snd_ctl_subscribe_events(card_data->handle, true);
+		if (err < 0) {
+			ksft_exit_fail_msg("snd_ctl_subscribe_events() failed for card %d: %d\n",
+					   card, err);
+		}
+
+		err = snd_ctl_poll_descriptors_count(card_data->handle);
+		if (err != 1) {
+			ksft_exit_fail_msg("Unexpected descriptor count %d for card %d\n",
+					   err, card);
+		}
+
+		err = snd_ctl_poll_descriptors(card_data->handle,
+					       &card_data->pollfd, 1);
+		if (err != 1) {
+			ksft_exit_fail_msg("snd_ctl_poll_descriptors() failed for card %d: %d\n",
+				       card, err);
+		}
+
+	next_card:
+		if (snd_card_next(&card) < 0) {
+			ksft_print_msg("snd_card_next");
+			break;
+		}
+	}
+
+	snd_config_delete(config);
+}
+
+/*
+ * Block for up to timeout ms for an event, returns a negative value
+ * on error, 0 for no event and 1 for an event.
+ */
+static int wait_for_event(struct ctl_data *ctl, int timeout)
+{
+	unsigned short revents;
+	snd_ctl_event_t *event;
+	int err;
+	unsigned int mask = 0;
+	unsigned int ev_id;
+
+	snd_ctl_event_alloca(&event);
+
+	do {
+		err = poll(&(ctl->card->pollfd), 1, timeout);
+		if (err < 0) {
+			ksft_print_msg("poll() failed for %s: %s (%d)\n",
+				       ctl->name, strerror(errno), errno);
+			return -1;
+		}
+		/* Timeout */
+		if (err == 0)
+			return 0;
+
+		err = snd_ctl_poll_descriptors_revents(ctl->card->handle,
+						       &(ctl->card->pollfd),
+						       1, &revents);
+		if (err < 0) {
+			ksft_print_msg("snd_ctl_poll_descriptors_revents() failed for %s: %d\n",
+				       ctl->name, err);
+			return err;
+		}
+		if (revents & POLLERR) {
+			ksft_print_msg("snd_ctl_poll_descriptors_revents() reported POLLERR for %s\n",
+				       ctl->name);
+			return -1;
+		}
+		/* No read events */
+		if (!(revents & POLLIN)) {
+			ksft_print_msg("No POLLIN\n");
+			continue;
+		}
+
+		err = snd_ctl_read(ctl->card->handle, event);
+		if (err < 0) {
+			ksft_print_msg("snd_ctl_read() failed for %s: %d\n",
+			       ctl->name, err);
+			return err;
+		}
+
+		if (snd_ctl_event_get_type(event) != SND_CTL_EVENT_ELEM)
+			continue;
+
+		/* The ID returned from the event is 1 less than numid */
+		mask = snd_ctl_event_elem_get_mask(event);
+		ev_id = snd_ctl_event_elem_get_numid(event);
+		if (ev_id != snd_ctl_elem_info_get_numid(ctl->info)) {
+			ksft_print_msg("Event for unexpected ctl %s\n",
+				       snd_ctl_event_elem_get_name(event));
+			continue;
+		}
+
+		if ((mask & SND_CTL_EVENT_MASK_REMOVE) == SND_CTL_EVENT_MASK_REMOVE) {
+			ksft_print_msg("Removal event for %s\n",
+				       ctl->name);
+			return -1;
+		}
+	} while ((mask & SND_CTL_EVENT_MASK_VALUE) != SND_CTL_EVENT_MASK_VALUE);
+
+	return 1;
+}
+
+static bool ctl_value_index_valid(struct ctl_data *ctl,
+				  snd_ctl_elem_value_t *val,
+				  int index)
+{
+	long int_val;
+	long long int64_val;
+
+	switch (snd_ctl_elem_info_get_type(ctl->info)) {
+	case SND_CTL_ELEM_TYPE_NONE:
+		ksft_print_msg("%s.%d Invalid control type NONE\n",
+			       ctl->name, index);
+		return false;
+
+	case SND_CTL_ELEM_TYPE_BOOLEAN:
+		int_val = snd_ctl_elem_value_get_boolean(val, index);
+		switch (int_val) {
+		case 0:
+		case 1:
+			break;
+		default:
+			ksft_print_msg("%s.%d Invalid boolean value %ld\n",
+				       ctl->name, index, int_val);
+			return false;
+		}
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER:
+		int_val = snd_ctl_elem_value_get_integer(val, index);
+
+		if (int_val < snd_ctl_elem_info_get_min(ctl->info)) {
+			ksft_print_msg("%s.%d value %ld less than minimum %ld\n",
+				       ctl->name, index, int_val,
+				       snd_ctl_elem_info_get_min(ctl->info));
+			return false;
+		}
+
+		if (int_val > snd_ctl_elem_info_get_max(ctl->info)) {
+			ksft_print_msg("%s.%d value %ld more than maximum %ld\n",
+				       ctl->name, index, int_val,
+				       snd_ctl_elem_info_get_max(ctl->info));
+			return false;
+		}
+
+		/* Only check step size if there is one and we're in bounds */
+		if (snd_ctl_elem_info_get_step(ctl->info) &&
+		    (int_val - snd_ctl_elem_info_get_min(ctl->info) %
+		     snd_ctl_elem_info_get_step(ctl->info))) {
+			ksft_print_msg("%s.%d value %ld invalid for step %ld minimum %ld\n",
+				       ctl->name, index, int_val,
+				       snd_ctl_elem_info_get_step(ctl->info),
+				       snd_ctl_elem_info_get_min(ctl->info));
+			return false;
+		}
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER64:
+		int64_val = snd_ctl_elem_value_get_integer64(val, index);
+
+		if (int64_val < snd_ctl_elem_info_get_min64(ctl->info)) {
+			ksft_print_msg("%s.%d value %lld less than minimum %lld\n",
+				       ctl->name, index, int64_val,
+				       snd_ctl_elem_info_get_min64(ctl->info));
+			return false;
+		}
+
+		if (int64_val > snd_ctl_elem_info_get_max64(ctl->info)) {
+			ksft_print_msg("%s.%d value %lld more than maximum %lld\n",
+				       ctl->name, index, int64_val,
+				       snd_ctl_elem_info_get_max64(ctl->info));
+			return false;
+		}
+
+		/* Only check step size if there is one and we're in bounds */
+		if (snd_ctl_elem_info_get_step64(ctl->info) &&
+		    (int64_val - snd_ctl_elem_info_get_min64(ctl->info)) %
+		    snd_ctl_elem_info_get_step64(ctl->info)) {
+			ksft_print_msg("%s.%d value %lld invalid for step %lld minimum %lld\n",
+				       ctl->name, index, int64_val,
+				       snd_ctl_elem_info_get_step64(ctl->info),
+				       snd_ctl_elem_info_get_min64(ctl->info));
+			return false;
+		}
+		break;
+
+	case SND_CTL_ELEM_TYPE_ENUMERATED:
+		int_val = snd_ctl_elem_value_get_enumerated(val, index);
+
+		if (int_val < 0) {
+			ksft_print_msg("%s.%d negative value %ld for enumeration\n",
+				       ctl->name, index, int_val);
+			return false;
+		}
+
+		if (int_val >= snd_ctl_elem_info_get_items(ctl->info)) {
+			ksft_print_msg("%s.%d value %ld more than item count %u\n",
+				       ctl->name, index, int_val,
+				       snd_ctl_elem_info_get_items(ctl->info));
+			return false;
+		}
+		break;
+
+	default:
+		/* No tests for other types */
+		break;
+	}
+
+	return true;
+}
+
+/*
+ * Check that the provided value meets the constraints for the
+ * provided control.
+ */
+static bool ctl_value_valid(struct ctl_data *ctl, snd_ctl_elem_value_t *val)
+{
+	int i;
+	bool valid = true;
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++)
+		if (!ctl_value_index_valid(ctl, val, i))
+			valid = false;
+
+	return valid;
+}
+
+/*
+ * Check that we can read the default value and it is valid. Write
+ * tests use the read value to restore the default.
+ */
+static void test_ctl_get_value(struct ctl_data *ctl)
+{
+	int err;
+
+	/* If the control is turned off let's be polite */
+	if (snd_ctl_elem_info_is_inactive(ctl->info)) {
+		ksft_print_msg("%s is inactive\n", ctl->name);
+		ksft_test_result_skip("get_value.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	/* Can't test reading on an unreadable control */
+	if (!snd_ctl_elem_info_is_readable(ctl->info)) {
+		ksft_print_msg("%s is not readable\n", ctl->name);
+		ksft_test_result_skip("get_value.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	err = snd_ctl_elem_read(ctl->card->handle, ctl->def_val);
+	if (err < 0) {
+		ksft_print_msg("snd_ctl_elem_read() failed: %s\n",
+			       snd_strerror(err));
+		goto out;
+	}
+
+	if (!ctl_value_valid(ctl, ctl->def_val))
+		err = -EINVAL;
+
+out:
+	ksft_test_result(err >= 0, "get_value.%s.%d\n",
+			 ctl->card->card_name, ctl->elem);
+}
+
+static bool strend(const char *haystack, const char *needle)
+{
+	size_t haystack_len = strlen(haystack);
+	size_t needle_len = strlen(needle);
+
+	if (needle_len > haystack_len)
+		return false;
+	return strcmp(haystack + haystack_len - needle_len, needle) == 0;
+}
+
+static void test_ctl_name(struct ctl_data *ctl)
+{
+	bool name_ok = true;
+
+	ksft_print_msg("%s.%d %s\n", ctl->card->card_name, ctl->elem,
+		       ctl->name);
+
+	/* Only boolean controls should end in Switch */
+	if (strend(ctl->name, " Switch")) {
+		if (snd_ctl_elem_info_get_type(ctl->info) != SND_CTL_ELEM_TYPE_BOOLEAN) {
+			ksft_print_msg("%d.%d %s ends in Switch but is not boolean\n",
+				       ctl->card->card, ctl->elem, ctl->name);
+			name_ok = false;
+		}
+	}
+
+	/* Writeable boolean controls should end in Switch */
+	if (snd_ctl_elem_info_get_type(ctl->info) == SND_CTL_ELEM_TYPE_BOOLEAN &&
+	    snd_ctl_elem_info_is_writable(ctl->info)) {
+		if (!strend(ctl->name, " Switch")) {
+			ksft_print_msg("%d.%d %s is a writeable boolean but not a Switch\n",
+				       ctl->card->card, ctl->elem, ctl->name);
+			name_ok = false;
+		}
+	}
+
+	ksft_test_result(name_ok, "name.%s.%d\n",
+			 ctl->card->card_name, ctl->elem);
+}
+
+static void show_values(struct ctl_data *ctl, snd_ctl_elem_value_t *orig_val,
+			snd_ctl_elem_value_t *read_val)
+{
+	long long orig_int, read_int;
+	int i;
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		switch (snd_ctl_elem_info_get_type(ctl->info)) {
+		case SND_CTL_ELEM_TYPE_BOOLEAN:
+			orig_int = snd_ctl_elem_value_get_boolean(orig_val, i);
+			read_int = snd_ctl_elem_value_get_boolean(read_val, i);
+			break;
+
+		case SND_CTL_ELEM_TYPE_INTEGER:
+			orig_int = snd_ctl_elem_value_get_integer(orig_val, i);
+			read_int = snd_ctl_elem_value_get_integer(read_val, i);
+			break;
+
+		case SND_CTL_ELEM_TYPE_INTEGER64:
+			orig_int = snd_ctl_elem_value_get_integer64(orig_val,
+								    i);
+			read_int = snd_ctl_elem_value_get_integer64(read_val,
+								    i);
+			break;
+
+		case SND_CTL_ELEM_TYPE_ENUMERATED:
+			orig_int = snd_ctl_elem_value_get_enumerated(orig_val,
+								     i);
+			read_int = snd_ctl_elem_value_get_enumerated(read_val,
+								     i);
+			break;
+
+		default:
+			return;
+		}
+
+		ksft_print_msg("%s.%d orig %lld read %lld, is_volatile %d\n",
+			       ctl->name, i, orig_int, read_int,
+			       snd_ctl_elem_info_is_volatile(ctl->info));
+	}
+}
+
+static bool show_mismatch(struct ctl_data *ctl, int index,
+			  snd_ctl_elem_value_t *read_val,
+			  snd_ctl_elem_value_t *expected_val)
+{
+	long long expected_int, read_int;
+
+	/*
+	 * We factor out the code to compare values representable as
+	 * integers, ensure that check doesn't log otherwise.
+	 */
+	expected_int = 0;
+	read_int = 0;
+
+	switch (snd_ctl_elem_info_get_type(ctl->info)) {
+	case SND_CTL_ELEM_TYPE_BOOLEAN:
+		expected_int = snd_ctl_elem_value_get_boolean(expected_val,
+							      index);
+		read_int = snd_ctl_elem_value_get_boolean(read_val, index);
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER:
+		expected_int = snd_ctl_elem_value_get_integer(expected_val,
+							      index);
+		read_int = snd_ctl_elem_value_get_integer(read_val, index);
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER64:
+		expected_int = snd_ctl_elem_value_get_integer64(expected_val,
+								index);
+		read_int = snd_ctl_elem_value_get_integer64(read_val,
+							    index);
+		break;
+
+	case SND_CTL_ELEM_TYPE_ENUMERATED:
+		expected_int = snd_ctl_elem_value_get_enumerated(expected_val,
+								 index);
+		read_int = snd_ctl_elem_value_get_enumerated(read_val,
+							     index);
+		break;
+
+	default:
+		break;
+	}
+
+	if (expected_int != read_int) {
+		/*
+		 * NOTE: The volatile attribute means that the hardware
+		 * can voluntarily change the state of control element
+		 * independent of any operation by software.  
+		 */
+		bool is_volatile = snd_ctl_elem_info_is_volatile(ctl->info);
+		ksft_print_msg("%s.%d expected %lld but read %lld, is_volatile %d\n",
+			       ctl->name, index, expected_int, read_int, is_volatile);
+		return !is_volatile;
+	} else {
+		return false;
+	}
+}
+
+/*
+ * Write a value then if possible verify that we get the expected
+ * result.  An optional expected value can be provided if we expect
+ * the write to fail, for verifying that invalid writes don't corrupt
+ * anything.
+ */
+static int write_and_verify(struct ctl_data *ctl,
+			    snd_ctl_elem_value_t *write_val,
+			    snd_ctl_elem_value_t *expected_val)
+{
+	int err, i;
+	bool error_expected, mismatch_shown;
+	snd_ctl_elem_value_t *initial_val, *read_val, *w_val;
+	snd_ctl_elem_value_alloca(&initial_val);
+	snd_ctl_elem_value_alloca(&read_val);
+	snd_ctl_elem_value_alloca(&w_val);
+
+	/*
+	 * We need to copy the write value since writing can modify
+	 * the value which causes surprises, and allocate an expected
+	 * value if we expect to read back what we wrote.
+	 */
+	snd_ctl_elem_value_copy(w_val, write_val);
+	if (expected_val) {
+		error_expected = true;
+	} else {
+		error_expected = false;
+		snd_ctl_elem_value_alloca(&expected_val);
+		snd_ctl_elem_value_copy(expected_val, write_val);
+	}
+
+	/* Store the value before we write */
+	if (snd_ctl_elem_info_is_readable(ctl->info)) {
+		snd_ctl_elem_value_set_id(initial_val, ctl->id);
+
+		err = snd_ctl_elem_read(ctl->card->handle, initial_val);
+		if (err < 0) {
+			ksft_print_msg("snd_ctl_elem_read() failed: %s\n",
+				       snd_strerror(err));
+			return err;
+		}
+	}
+
+	/*
+	 * Do the write, if we have an expected value ignore the error
+	 * and carry on to validate the expected value.
+	 */
+	err = snd_ctl_elem_write(ctl->card->handle, w_val);
+	if (err < 0 && !error_expected) {
+		ksft_print_msg("snd_ctl_elem_write() failed: %s\n",
+			       snd_strerror(err));
+		return err;
+	}
+
+	/* Can we do the verification part? */
+	if (!snd_ctl_elem_info_is_readable(ctl->info))
+		return err;
+
+	snd_ctl_elem_value_set_id(read_val, ctl->id);
+
+	err = snd_ctl_elem_read(ctl->card->handle, read_val);
+	if (err < 0) {
+		ksft_print_msg("snd_ctl_elem_read() failed: %s\n",
+			       snd_strerror(err));
+		return err;
+	}
+
+	/*
+	 * We can't verify any specific value for volatile controls
+	 * but we should still check that whatever we read is a valid
+	 * vale for the control.
+	 */
+	if (snd_ctl_elem_info_is_volatile(ctl->info)) {
+		if (!ctl_value_valid(ctl, read_val)) {
+			ksft_print_msg("Volatile control %s has invalid value\n",
+				       ctl->name);
+			return -EINVAL;
+		}
+
+		return 0;
+	}
+
+	/*
+	 * Check for an event if the value changed, or confirm that
+	 * there was none if it didn't.  We rely on the kernel
+	 * generating the notification before it returns from the
+	 * write, this is currently true, should that ever change this
+	 * will most likely break and need updating.
+	 */
+	err = wait_for_event(ctl, 0);
+	if (snd_ctl_elem_value_compare(initial_val, read_val)) {
+		if (err < 1) {
+			ksft_print_msg("No event generated for %s\n",
+				       ctl->name);
+			show_values(ctl, initial_val, read_val);
+			ctl->event_missing++;
+		}
+	} else {
+		if (err != 0) {
+			ksft_print_msg("Spurious event generated for %s\n",
+				       ctl->name);
+			show_values(ctl, initial_val, read_val);
+			ctl->event_spurious++;
+		}
+	}
+
+	/*
+	 * Use the libray to compare values, if there's a mismatch
+	 * carry on and try to provide a more useful diagnostic than
+	 * just "mismatch".
+	 */
+	if (!snd_ctl_elem_value_compare(expected_val, read_val))
+		return 0;
+
+	mismatch_shown = false;
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++)
+		if (show_mismatch(ctl, i, read_val, expected_val))
+			mismatch_shown = true;
+
+	if (!mismatch_shown)
+		ksft_print_msg("%s read and written values differ\n",
+			       ctl->name);
+
+	return -1;
+}
+
+/*
+ * Make sure we can write the default value back to the control, this
+ * should validate that at least some write works.
+ */
+static void test_ctl_write_default(struct ctl_data *ctl)
+{
+	int err;
+
+	/* If the control is turned off let's be polite */
+	if (snd_ctl_elem_info_is_inactive(ctl->info)) {
+		ksft_print_msg("%s is inactive\n", ctl->name);
+		ksft_test_result_skip("write_default.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	if (!snd_ctl_elem_info_is_writable(ctl->info)) {
+		ksft_print_msg("%s is not writeable\n", ctl->name);
+		ksft_test_result_skip("write_default.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	/* No idea what the default was for unreadable controls */
+	if (!snd_ctl_elem_info_is_readable(ctl->info)) {
+		ksft_print_msg("%s couldn't read default\n", ctl->name);
+		ksft_test_result_skip("write_default.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	err = write_and_verify(ctl, ctl->def_val, NULL);
+
+	ksft_test_result(err >= 0, "write_default.%s.%d\n",
+			 ctl->card->card_name, ctl->elem);
+}
+
+static bool test_ctl_write_valid_boolean(struct ctl_data *ctl)
+{
+	int err, i, j;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	snd_ctl_elem_value_set_id(val, ctl->id);
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		for (j = 0; j < 2; j++) {
+			snd_ctl_elem_value_set_boolean(val, i, j);
+			err = write_and_verify(ctl, val, NULL);
+			if (err != 0)
+				fail = true;
+		}
+	}
+
+	return !fail;
+}
+
+static bool test_ctl_write_valid_integer(struct ctl_data *ctl)
+{
+	int err;
+	int i;
+	long j, step;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	snd_ctl_elem_value_set_id(val, ctl->id);
+
+	step = snd_ctl_elem_info_get_step(ctl->info);
+	if (!step)
+		step = 1;
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		for (j = snd_ctl_elem_info_get_min(ctl->info);
+		     j <= snd_ctl_elem_info_get_max(ctl->info); j += step) {
+
+			snd_ctl_elem_value_set_integer(val, i, j);
+			err = write_and_verify(ctl, val, NULL);
+			if (err != 0)
+				fail = true;
+		}
+	}
+
+
+	return !fail;
+}
+
+static bool test_ctl_write_valid_integer64(struct ctl_data *ctl)
+{
+	int err, i;
+	long long j, step;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	snd_ctl_elem_value_set_id(val, ctl->id);
+
+	step = snd_ctl_elem_info_get_step64(ctl->info);
+	if (!step)
+		step = 1;
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		for (j = snd_ctl_elem_info_get_min64(ctl->info);
+		     j <= snd_ctl_elem_info_get_max64(ctl->info); j += step) {
+
+			snd_ctl_elem_value_set_integer64(val, i, j);
+			err = write_and_verify(ctl, val, NULL);
+			if (err != 0)
+				fail = true;
+		}
+	}
+
+	return !fail;
+}
+
+static bool test_ctl_write_valid_enumerated(struct ctl_data *ctl)
+{
+	int err, i, j;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	snd_ctl_elem_value_set_id(val, ctl->id);
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		for (j = 0; j < snd_ctl_elem_info_get_items(ctl->info); j++) {
+			snd_ctl_elem_value_set_enumerated(val, i, j);
+			err = write_and_verify(ctl, val, NULL);
+			if (err != 0)
+				fail = true;
+		}
+	}
+
+	return !fail;
+}
+
+static void test_ctl_write_valid(struct ctl_data *ctl)
+{
+	bool pass;
+
+	/* If the control is turned off let's be polite */
+	if (snd_ctl_elem_info_is_inactive(ctl->info)) {
+		ksft_print_msg("%s is inactive\n", ctl->name);
+		ksft_test_result_skip("write_valid.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	if (!snd_ctl_elem_info_is_writable(ctl->info)) {
+		ksft_print_msg("%s is not writeable\n", ctl->name);
+		ksft_test_result_skip("write_valid.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	switch (snd_ctl_elem_info_get_type(ctl->info)) {
+	case SND_CTL_ELEM_TYPE_BOOLEAN:
+		pass = test_ctl_write_valid_boolean(ctl);
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER:
+		pass = test_ctl_write_valid_integer(ctl);
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER64:
+		pass = test_ctl_write_valid_integer64(ctl);
+		break;
+
+	case SND_CTL_ELEM_TYPE_ENUMERATED:
+		pass = test_ctl_write_valid_enumerated(ctl);
+		break;
+
+	default:
+		/* No tests for this yet */
+		ksft_test_result_skip("write_valid.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	/* Restore the default value to minimise disruption */
+	write_and_verify(ctl, ctl->def_val, NULL);
+
+	ksft_test_result(pass, "write_valid.%s.%d\n",
+			 ctl->card->card_name, ctl->elem);
+}
+
+static bool test_ctl_write_invalid_value(struct ctl_data *ctl,
+					 snd_ctl_elem_value_t *val)
+{
+	int err;
+
+	/* Ideally this will fail... */
+	err = snd_ctl_elem_write(ctl->card->handle, val);
+	if (err < 0)
+		return false;
+
+	/* ...but some devices will clamp to an in range value */
+	err = snd_ctl_elem_read(ctl->card->handle, val);
+	if (err < 0) {
+		ksft_print_msg("%s failed to read: %s\n",
+			       ctl->name, snd_strerror(err));
+		return true;
+	}
+
+	return !ctl_value_valid(ctl, val);
+}
+
+static bool test_ctl_write_invalid_boolean(struct ctl_data *ctl)
+{
+	int i;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		snd_ctl_elem_value_copy(val, ctl->def_val);
+		snd_ctl_elem_value_set_boolean(val, i, 2);
+
+		if (test_ctl_write_invalid_value(ctl, val))
+			fail = true;
+	}
+
+	return !fail;
+}
+
+static bool test_ctl_write_invalid_integer(struct ctl_data *ctl)
+{
+	int i;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		if (snd_ctl_elem_info_get_min(ctl->info) != LONG_MIN) {
+			/* Just under range */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer(val, i,
+			       snd_ctl_elem_info_get_min(ctl->info) - 1);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+
+			/* Minimum representable value */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer(val, i, LONG_MIN);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+		}
+
+		if (snd_ctl_elem_info_get_max(ctl->info) != LONG_MAX) {
+			/* Just over range */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer(val, i,
+			       snd_ctl_elem_info_get_max(ctl->info) + 1);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+
+			/* Maximum representable value */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer(val, i, LONG_MAX);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+		}
+	}
+
+	return !fail;
+}
+
+static bool test_ctl_write_invalid_integer64(struct ctl_data *ctl)
+{
+	int i;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		if (snd_ctl_elem_info_get_min64(ctl->info) != LLONG_MIN) {
+			/* Just under range */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer64(val, i,
+				snd_ctl_elem_info_get_min64(ctl->info) - 1);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+
+			/* Minimum representable value */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer64(val, i, LLONG_MIN);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+		}
+
+		if (snd_ctl_elem_info_get_max64(ctl->info) != LLONG_MAX) {
+			/* Just over range */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer64(val, i,
+				snd_ctl_elem_info_get_max64(ctl->info) + 1);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+
+			/* Maximum representable value */
+			snd_ctl_elem_value_copy(val, ctl->def_val);
+			snd_ctl_elem_value_set_integer64(val, i, LLONG_MAX);
+
+			if (test_ctl_write_invalid_value(ctl, val))
+				fail = true;
+		}
+	}
+
+	return !fail;
+}
+
+static bool test_ctl_write_invalid_enumerated(struct ctl_data *ctl)
+{
+	int i;
+	bool fail = false;
+	snd_ctl_elem_value_t *val;
+	snd_ctl_elem_value_alloca(&val);
+
+	snd_ctl_elem_value_set_id(val, ctl->id);
+
+	for (i = 0; i < snd_ctl_elem_info_get_count(ctl->info); i++) {
+		/* One beyond maximum */
+		snd_ctl_elem_value_copy(val, ctl->def_val);
+		snd_ctl_elem_value_set_enumerated(val, i,
+				  snd_ctl_elem_info_get_items(ctl->info));
+
+		if (test_ctl_write_invalid_value(ctl, val))
+			fail = true;
+
+		/* Maximum representable value */
+		snd_ctl_elem_value_copy(val, ctl->def_val);
+		snd_ctl_elem_value_set_enumerated(val, i, UINT_MAX);
+
+		if (test_ctl_write_invalid_value(ctl, val))
+			fail = true;
+
+	}
+
+	return !fail;
+}
+
+
+static void test_ctl_write_invalid(struct ctl_data *ctl)
+{
+	bool pass;
+
+	/* If the control is turned off let's be polite */
+	if (snd_ctl_elem_info_is_inactive(ctl->info)) {
+		ksft_print_msg("%s is inactive\n", ctl->name);
+		ksft_test_result_skip("write_invalid.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	if (!snd_ctl_elem_info_is_writable(ctl->info)) {
+		ksft_print_msg("%s is not writeable\n", ctl->name);
+		ksft_test_result_skip("write_invalid.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	switch (snd_ctl_elem_info_get_type(ctl->info)) {
+	case SND_CTL_ELEM_TYPE_BOOLEAN:
+		pass = test_ctl_write_invalid_boolean(ctl);
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER:
+		pass = test_ctl_write_invalid_integer(ctl);
+		break;
+
+	case SND_CTL_ELEM_TYPE_INTEGER64:
+		pass = test_ctl_write_invalid_integer64(ctl);
+		break;
+
+	case SND_CTL_ELEM_TYPE_ENUMERATED:
+		pass = test_ctl_write_invalid_enumerated(ctl);
+		break;
+
+	default:
+		/* No tests for this yet */
+		ksft_test_result_skip("write_invalid.%s.%d\n",
+				      ctl->card->card_name, ctl->elem);
+		return;
+	}
+
+	/* Restore the default value to minimise disruption */
+	write_and_verify(ctl, ctl->def_val, NULL);
+
+	ksft_test_result(pass, "write_invalid.%s.%d\n",
+			 ctl->card->card_name, ctl->elem);
+}
+
+static void test_ctl_event_missing(struct ctl_data *ctl)
+{
+	ksft_test_result(!ctl->event_missing, "event_missing.%s.%d\n",
+			 ctl->card->card_name, ctl->elem);
+}
+
+static void test_ctl_event_spurious(struct ctl_data *ctl)
+{
+	ksft_test_result(!ctl->event_spurious, "event_spurious.%s.%d\n",
+			 ctl->card->card_name, ctl->elem);
+}
+
+int main(void)
+{
+	struct ctl_data *ctl;
+
+	ksft_print_header();
+
+	find_controls();
+
+	ksft_set_plan(num_controls * TESTS_PER_CONTROL);
+
+	for (ctl = ctl_list; ctl != NULL; ctl = ctl->next) {
+		/*
+		 * Must test get_value() before we write anything, the
+		 * test stores the default value for later cleanup.
+		 */
+		test_ctl_get_value(ctl);
+		test_ctl_name(ctl);
+		test_ctl_write_default(ctl);
+		test_ctl_write_valid(ctl);
+		test_ctl_write_invalid(ctl);
+		test_ctl_event_missing(ctl);
+		test_ctl_event_spurious(ctl);
+	}
+
+	ksft_exit_pass();
+
+	return 0;
+}
diff --git a/tools/testing/selftests/alsa/pcm-test.c b/tools/testing/selftests/alsa/pcm-test.c
new file mode 100644
index 000000000..ee04ccef7
--- /dev/null
+++ b/tools/testing/selftests/alsa/pcm-test.c
@@ -0,0 +1,671 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// kselftest for the ALSA PCM API
+//
+// Original author: Jaroslav Kysela <perex@perex.cz>
+// Copyright (c) 2022 Red Hat Inc.
+
+// This test will iterate over all cards detected in the system, exercising
+// every PCM device it can find.  This may conflict with other system
+// software if there is audio activity so is best run on a system with a
+// minimal active userspace.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+#include <errno.h>
+#include <assert.h>
+#include <pthread.h>
+
+#include "kselftest.h"
+#include "alsa-local.h"
+
+typedef struct timespec timestamp_t;
+
+struct card_data {
+	int card;
+	snd_ctl_card_info_t *info;
+	const char *name;
+	pthread_t thread;
+	struct card_data *next;
+};
+
+struct card_data *card_list;
+
+struct pcm_data {
+	snd_pcm_t *handle;
+	int card;
+	int device;
+	int subdevice;
+	const char *card_name;
+	snd_pcm_stream_t stream;
+	snd_config_t *pcm_config;
+	struct pcm_data *next;
+};
+
+struct pcm_data *pcm_list;
+
+int num_missing;
+struct pcm_data *pcm_missing;
+
+snd_config_t *default_pcm_config;
+
+/* Lock while reporting results since kselftest doesn't */
+pthread_mutex_t results_lock = PTHREAD_MUTEX_INITIALIZER;
+
+enum test_class {
+	TEST_CLASS_DEFAULT,
+	TEST_CLASS_SYSTEM,
+};
+
+void timestamp_now(timestamp_t *tstamp)
+{
+	if (clock_gettime(CLOCK_MONOTONIC_RAW, tstamp))
+		ksft_exit_fail_msg("clock_get_time\n");
+}
+
+long long timestamp_diff_ms(timestamp_t *tstamp)
+{
+	timestamp_t now, diff;
+	timestamp_now(&now);
+	if (tstamp->tv_nsec > now.tv_nsec) {
+		diff.tv_sec = now.tv_sec - tstamp->tv_sec - 1;
+		diff.tv_nsec = (now.tv_nsec + 1000000000L) - tstamp->tv_nsec;
+	} else {
+		diff.tv_sec = now.tv_sec - tstamp->tv_sec;
+		diff.tv_nsec = now.tv_nsec - tstamp->tv_nsec;
+	}
+	return (diff.tv_sec * 1000) + ((diff.tv_nsec + 500000L) / 1000000L);
+}
+
+static long device_from_id(snd_config_t *node)
+{
+	const char *id;
+	char *end;
+	long v;
+
+	if (snd_config_get_id(node, &id))
+		ksft_exit_fail_msg("snd_config_get_id\n");
+	errno = 0;
+	v = strtol(id, &end, 10);
+	if (errno || *end)
+		return -1;
+	return v;
+}
+
+static void missing_device(int card, int device, int subdevice, snd_pcm_stream_t stream)
+{
+	struct pcm_data *pcm_data;
+
+	for (pcm_data = pcm_list; pcm_data != NULL; pcm_data = pcm_data->next) {
+		if (pcm_data->card != card)
+			continue;
+		if (pcm_data->device != device)
+			continue;
+		if (pcm_data->subdevice != subdevice)
+			continue;
+		if (pcm_data->stream != stream)
+			continue;
+		return;
+	}
+	pcm_data = calloc(1, sizeof(*pcm_data));
+	if (!pcm_data)
+		ksft_exit_fail_msg("Out of memory\n");
+	pcm_data->card = card;
+	pcm_data->device = device;
+	pcm_data->subdevice = subdevice;
+	pcm_data->stream = stream;
+	pcm_data->next = pcm_missing;
+	pcm_missing = pcm_data;
+	num_missing++;
+}
+
+static void missing_devices(int card, snd_config_t *card_config)
+{
+	snd_config_t *pcm_config, *node1, *node2;
+	snd_config_iterator_t i1, i2, next1, next2;
+	int device, subdevice;
+
+	pcm_config = conf_get_subtree(card_config, "pcm", NULL);
+	if (!pcm_config)
+		return;
+	snd_config_for_each(i1, next1, pcm_config) {
+		node1 = snd_config_iterator_entry(i1);
+		device = device_from_id(node1);
+		if (device < 0)
+			continue;
+		if (snd_config_get_type(node1) != SND_CONFIG_TYPE_COMPOUND)
+			continue;
+		snd_config_for_each(i2, next2, node1) {
+			node2 = snd_config_iterator_entry(i2);
+			subdevice = device_from_id(node2);
+			if (subdevice < 0)
+				continue;
+			if (conf_get_subtree(node2, "PLAYBACK", NULL))
+				missing_device(card, device, subdevice, SND_PCM_STREAM_PLAYBACK);
+			if (conf_get_subtree(node2, "CAPTURE", NULL))
+				missing_device(card, device, subdevice, SND_PCM_STREAM_CAPTURE);
+		}
+	}
+}
+
+static void find_pcms(void)
+{
+	char name[32], key[64];
+	char *card_name, *card_longname;
+	int card, dev, subdev, count, direction, err;
+	snd_pcm_stream_t stream;
+	struct pcm_data *pcm_data;
+	snd_ctl_t *handle;
+	snd_pcm_info_t *pcm_info;
+	snd_config_t *config, *card_config, *pcm_config;
+	struct card_data *card_data;
+
+	snd_pcm_info_alloca(&pcm_info);
+
+	card = -1;
+	if (snd_card_next(&card) < 0 || card < 0)
+		return;
+
+	config = get_alsalib_config();
+
+	while (card >= 0) {
+		card_data = calloc(1, sizeof(*card_data));
+		if (!card_data)
+			ksft_exit_fail_msg("Out of memory\n");
+
+		sprintf(name, "hw:%d", card);
+
+		err = snd_ctl_open_lconf(&handle, name, 0, config);
+		if (err < 0) {
+			ksft_print_msg("Failed to get hctl for card %d: %s\n",
+				       card, snd_strerror(err));
+			goto next_card;
+		}
+
+		err = snd_card_get_name(card, &card_name);
+		if (err != 0)
+			card_name = "Unknown";
+		err = snd_card_get_longname(card, &card_longname);
+		if (err != 0)
+			card_longname = "Unknown";
+
+		err = snd_ctl_card_info_malloc(&card_data->info);
+		if (err != 0)
+			ksft_exit_fail_msg("Failed to allocate card info: %d\n",
+				err);
+
+		err = snd_ctl_card_info(handle, card_data->info);
+		if (err == 0) {
+			card_data->name = snd_ctl_card_info_get_id(card_data->info);
+			if (!card_data->name)
+				ksft_print_msg("Failed to get card ID\n");
+		} else {
+			ksft_print_msg("Failed to get card info: %d\n", err);
+		}
+
+		if (!card_data->name)
+			card_data->name = "Unknown";
+
+		ksft_print_msg("Card %d/%s - %s (%s)\n", card,
+			       card_data->name, card_name, card_longname);
+
+		card_config = conf_by_card(card);
+
+		card_data->card = card;
+		card_data->next = card_list;
+		card_list = card_data;
+
+		dev = -1;
+		while (1) {
+			if (snd_ctl_pcm_next_device(handle, &dev) < 0)
+				ksft_exit_fail_msg("snd_ctl_pcm_next_device\n");
+			if (dev < 0)
+				break;
+
+			for (direction = 0; direction < 2; direction++) {
+				stream = direction ? SND_PCM_STREAM_CAPTURE : SND_PCM_STREAM_PLAYBACK;
+				sprintf(key, "pcm.%d.%s", dev, snd_pcm_stream_name(stream));
+				pcm_config = conf_get_subtree(card_config, key, NULL);
+				if (conf_get_bool(card_config, key, "skip", false)) {
+					ksft_print_msg("skipping pcm %d.%d.%s\n", card, dev, snd_pcm_stream_name(stream));
+					continue;
+				}
+				snd_pcm_info_set_device(pcm_info, dev);
+				snd_pcm_info_set_subdevice(pcm_info, 0);
+				snd_pcm_info_set_stream(pcm_info, stream);
+				err = snd_ctl_pcm_info(handle, pcm_info);
+				if (err == -ENOENT)
+					continue;
+				if (err < 0)
+					ksft_exit_fail_msg("snd_ctl_pcm_info: %d:%d:%d\n",
+							   dev, 0, stream);
+
+				ksft_print_msg("%s.0 - %s\n", card_data->name,
+					       snd_pcm_info_get_id(pcm_info));
+
+				count = snd_pcm_info_get_subdevices_count(pcm_info);
+				for (subdev = 0; subdev < count; subdev++) {
+					sprintf(key, "pcm.%d.%d.%s", dev, subdev, snd_pcm_stream_name(stream));
+					if (conf_get_bool(card_config, key, "skip", false)) {
+						ksft_print_msg("skipping pcm %d.%d.%d.%s\n", card, dev,
+							       subdev, snd_pcm_stream_name(stream));
+						continue;
+					}
+					pcm_data = calloc(1, sizeof(*pcm_data));
+					if (!pcm_data)
+						ksft_exit_fail_msg("Out of memory\n");
+					pcm_data->card = card;
+					pcm_data->device = dev;
+					pcm_data->subdevice = subdev;
+					pcm_data->card_name = card_data->name;
+					pcm_data->stream = stream;
+					pcm_data->pcm_config = conf_get_subtree(card_config, key, NULL);
+					pcm_data->next = pcm_list;
+					pcm_list = pcm_data;
+				}
+			}
+		}
+
+		/* check for missing devices */
+		missing_devices(card, card_config);
+
+	next_card:
+		snd_ctl_close(handle);
+		if (snd_card_next(&card) < 0) {
+			ksft_print_msg("snd_card_next");
+			break;
+		}
+	}
+
+	snd_config_delete(config);
+}
+
+static void test_pcm_time(struct pcm_data *data, enum test_class class,
+			  const char *test_name, snd_config_t *pcm_cfg)
+{
+	char name[64], msg[256];
+	const int duration_s = 2, margin_ms = 100;
+	const int duration_ms = duration_s * 1000;
+	const char *cs;
+	int i, err;
+	snd_pcm_t *handle = NULL;
+	snd_pcm_access_t access = SND_PCM_ACCESS_RW_INTERLEAVED;
+	snd_pcm_format_t format, old_format;
+	const char *alt_formats[8];
+	unsigned char *samples = NULL;
+	snd_pcm_sframes_t frames;
+	long long ms;
+	long rate, channels, period_size, buffer_size;
+	unsigned int rrate;
+	snd_pcm_uframes_t rperiod_size, rbuffer_size, start_threshold;
+	timestamp_t tstamp;
+	bool pass = false;
+	snd_pcm_hw_params_t *hw_params;
+	snd_pcm_sw_params_t *sw_params;
+	const char *test_class_name;
+	bool skip = true;
+	const char *desc;
+
+	switch (class) {
+	case TEST_CLASS_DEFAULT:
+		test_class_name = "default";
+		break;
+	case TEST_CLASS_SYSTEM:
+		test_class_name = "system";
+		break;
+	default:
+		ksft_exit_fail_msg("Unknown test class %d\n", class);
+		break;
+	}
+
+	desc = conf_get_string(pcm_cfg, "description", NULL, NULL);
+	if (desc)
+		ksft_print_msg("%s.%s.%s.%d.%d.%s - %s\n",
+			       test_class_name, test_name,
+			       data->card_name, data->device, data->subdevice,
+			       snd_pcm_stream_name(data->stream),
+			       desc);
+
+
+	snd_pcm_hw_params_alloca(&hw_params);
+	snd_pcm_sw_params_alloca(&sw_params);
+
+	cs = conf_get_string(pcm_cfg, "format", NULL, "S16_LE");
+	format = snd_pcm_format_value(cs);
+	if (format == SND_PCM_FORMAT_UNKNOWN)
+		ksft_exit_fail_msg("Wrong format '%s'\n", cs);
+	conf_get_string_array(pcm_cfg, "alt_formats", NULL,
+				alt_formats, ARRAY_SIZE(alt_formats), NULL);
+	rate = conf_get_long(pcm_cfg, "rate", NULL, 48000);
+	channels = conf_get_long(pcm_cfg, "channels", NULL, 2);
+	period_size = conf_get_long(pcm_cfg, "period_size", NULL, 4096);
+	buffer_size = conf_get_long(pcm_cfg, "buffer_size", NULL, 16384);
+
+	samples = malloc((rate * channels * snd_pcm_format_physical_width(format)) / 8);
+	if (!samples)
+		ksft_exit_fail_msg("Out of memory\n");
+	snd_pcm_format_set_silence(format, samples, rate * channels);
+
+	sprintf(name, "hw:%d,%d,%d", data->card, data->device, data->subdevice);
+	err = snd_pcm_open(&handle, name, data->stream, 0);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "Failed to get pcm handle: %s", snd_strerror(err));
+		goto __close;
+	}
+
+	err = snd_pcm_hw_params_any(handle, hw_params);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_any: %s", snd_strerror(err));
+		goto __close;
+	}
+	err = snd_pcm_hw_params_set_rate_resample(handle, hw_params, 0);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_set_rate_resample: %s", snd_strerror(err));
+		goto __close;
+	}
+	err = snd_pcm_hw_params_set_access(handle, hw_params, access);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_set_access %s: %s",
+					   snd_pcm_access_name(access), snd_strerror(err));
+		goto __close;
+	}
+	i = -1;
+__format:
+	err = snd_pcm_hw_params_set_format(handle, hw_params, format);
+	if (err < 0) {
+		i++;
+		if (i < ARRAY_SIZE(alt_formats) && alt_formats[i]) {
+			old_format = format;
+			format = snd_pcm_format_value(alt_formats[i]);
+			if (format != SND_PCM_FORMAT_UNKNOWN) {
+				ksft_print_msg("%s.%s.%d.%d.%s.%s format %s -> %s\n",
+						 test_name,
+						 data->card_name, data->device, data->subdevice,
+						 snd_pcm_stream_name(data->stream),
+						 snd_pcm_access_name(access),
+						 snd_pcm_format_name(old_format),
+						 snd_pcm_format_name(format));
+				samples = realloc(samples, (rate * channels *
+							    snd_pcm_format_physical_width(format)) / 8);
+				if (!samples)
+					ksft_exit_fail_msg("Out of memory\n");
+				snd_pcm_format_set_silence(format, samples, rate * channels);
+				goto __format;
+			}
+		}
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_set_format %s: %s",
+					   snd_pcm_format_name(format), snd_strerror(err));
+		goto __close;
+	}
+	err = snd_pcm_hw_params_set_channels(handle, hw_params, channels);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_set_channels %ld: %s", channels, snd_strerror(err));
+		goto __close;
+	}
+	rrate = rate;
+	err = snd_pcm_hw_params_set_rate_near(handle, hw_params, &rrate, 0);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_set_rate %ld: %s", rate, snd_strerror(err));
+		goto __close;
+	}
+	if (rrate != rate) {
+		snprintf(msg, sizeof(msg), "rate mismatch %ld != %u", rate, rrate);
+		goto __close;
+	}
+	rperiod_size = period_size;
+	err = snd_pcm_hw_params_set_period_size_near(handle, hw_params, &rperiod_size, 0);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_set_period_size %ld: %s", period_size, snd_strerror(err));
+		goto __close;
+	}
+	rbuffer_size = buffer_size;
+	err = snd_pcm_hw_params_set_buffer_size_near(handle, hw_params, &rbuffer_size);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params_set_buffer_size %ld: %s", buffer_size, snd_strerror(err));
+		goto __close;
+	}
+	err = snd_pcm_hw_params(handle, hw_params);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_hw_params: %s", snd_strerror(err));
+		goto __close;
+	}
+
+	err = snd_pcm_sw_params_current(handle, sw_params);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_sw_params_current: %s", snd_strerror(err));
+		goto __close;
+	}
+	if (data->stream == SND_PCM_STREAM_PLAYBACK) {
+		start_threshold = (rbuffer_size / rperiod_size) * rperiod_size;
+	} else {
+		start_threshold = rperiod_size;
+	}
+	err = snd_pcm_sw_params_set_start_threshold(handle, sw_params, start_threshold);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_sw_params_set_start_threshold %ld: %s", (long)start_threshold, snd_strerror(err));
+		goto __close;
+	}
+	err = snd_pcm_sw_params_set_avail_min(handle, sw_params, rperiod_size);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_sw_params_set_avail_min %ld: %s", (long)rperiod_size, snd_strerror(err));
+		goto __close;
+	}
+	err = snd_pcm_sw_params(handle, sw_params);
+	if (err < 0) {
+		snprintf(msg, sizeof(msg), "snd_pcm_sw_params: %s", snd_strerror(err));
+		goto __close;
+	}
+
+	ksft_print_msg("%s.%s.%s.%d.%d.%s hw_params.%s.%s.%ld.%ld.%ld.%ld sw_params.%ld\n",
+		         test_class_name, test_name,
+			 data->card_name, data->device, data->subdevice,
+			 snd_pcm_stream_name(data->stream),
+			 snd_pcm_access_name(access),
+			 snd_pcm_format_name(format),
+			 (long)rate, (long)channels,
+			 (long)rperiod_size, (long)rbuffer_size,
+			 (long)start_threshold);
+
+	/* Set all the params, actually run the test */
+	skip = false;
+
+	timestamp_now(&tstamp);
+	for (i = 0; i < duration_s; i++) {
+		if (data->stream == SND_PCM_STREAM_PLAYBACK) {
+			frames = snd_pcm_writei(handle, samples, rate);
+			if (frames < 0) {
+				snprintf(msg, sizeof(msg),
+					 "Write failed: expected %ld, wrote %li", rate, frames);
+				goto __close;
+			}
+			if (frames < rate) {
+				snprintf(msg, sizeof(msg),
+					 "expected %ld, wrote %li", rate, frames);
+				goto __close;
+			}
+		} else {
+			frames = snd_pcm_readi(handle, samples, rate);
+			if (frames < 0) {
+				snprintf(msg, sizeof(msg),
+					 "expected %ld, wrote %li", rate, frames);
+				goto __close;
+			}
+			if (frames < rate) {
+				snprintf(msg, sizeof(msg),
+					 "expected %ld, wrote %li", rate, frames);
+				goto __close;
+			}
+		}
+	}
+
+	snd_pcm_drain(handle);
+	ms = timestamp_diff_ms(&tstamp);
+	if (ms < duration_ms - margin_ms || ms > duration_ms + margin_ms) {
+		snprintf(msg, sizeof(msg), "time mismatch: expected %dms got %lld", duration_ms, ms);
+		goto __close;
+	}
+
+	msg[0] = '\0';
+	pass = true;
+__close:
+	pthread_mutex_lock(&results_lock);
+
+	switch (class) {
+	case TEST_CLASS_SYSTEM:
+		test_class_name = "system";
+		/*
+		 * Anything specified as specific to this system
+		 * should always be supported.
+		 */
+		ksft_test_result(!skip, "%s.%s.%s.%d.%d.%s.params\n",
+				 test_class_name, test_name,
+				 data->card_name, data->device,
+				 data->subdevice,
+				 snd_pcm_stream_name(data->stream));
+		break;
+	default:
+		break;
+	}
+
+	if (!skip)
+		ksft_test_result(pass, "%s.%s.%s.%d.%d.%s\n",
+				 test_class_name, test_name,
+				 data->card_name, data->device,
+				 data->subdevice,
+				 snd_pcm_stream_name(data->stream));
+	else
+		ksft_test_result_skip("%s.%s.%s.%d.%d.%s\n",
+				 test_class_name, test_name,
+				 data->card_name, data->device,
+				 data->subdevice,
+				 snd_pcm_stream_name(data->stream));
+
+	if (msg[0])
+		ksft_print_msg("%s\n", msg);
+
+	pthread_mutex_unlock(&results_lock);
+
+	free(samples);
+	if (handle)
+		snd_pcm_close(handle);
+}
+
+void run_time_tests(struct pcm_data *pcm, enum test_class class,
+		    snd_config_t *cfg)
+{
+	const char *test_name, *test_type;
+	snd_config_t *pcm_cfg;
+	snd_config_iterator_t i, next;
+
+	if (!cfg)
+		return;
+
+	cfg = conf_get_subtree(cfg, "test", NULL);
+	if (cfg == NULL)
+		return;
+
+	snd_config_for_each(i, next, cfg) {
+		pcm_cfg = snd_config_iterator_entry(i);
+		if (snd_config_get_id(pcm_cfg, &test_name) < 0)
+			ksft_exit_fail_msg("snd_config_get_id\n");
+		test_type = conf_get_string(pcm_cfg, "type", NULL, "time");
+		if (strcmp(test_type, "time") == 0)
+			test_pcm_time(pcm, class, test_name, pcm_cfg);
+		else
+			ksft_exit_fail_msg("unknown test type '%s'\n", test_type);
+	}
+}
+
+void *card_thread(void *data)
+{
+	struct card_data *card = data;
+	struct pcm_data *pcm;
+
+	for (pcm = pcm_list; pcm != NULL; pcm = pcm->next) {
+		if (pcm->card != card->card)
+			continue;
+
+		run_time_tests(pcm, TEST_CLASS_DEFAULT, default_pcm_config);
+		run_time_tests(pcm, TEST_CLASS_SYSTEM, pcm->pcm_config);
+	}
+
+	return 0;
+}
+
+int main(void)
+{
+	struct card_data *card;
+	struct card_cfg_data *conf;
+	struct pcm_data *pcm;
+	snd_config_t *global_config, *cfg;
+	int num_pcm_tests = 0, num_tests, num_std_pcm_tests;
+	int ret;
+	void *thread_ret;
+
+	ksft_print_header();
+
+	global_config = conf_load_from_file("pcm-test.conf");
+	default_pcm_config = conf_get_subtree(global_config, "pcm", NULL);
+	if (default_pcm_config == NULL)
+		ksft_exit_fail_msg("default pcm test configuration (pcm compound) is missing\n");
+
+	conf_load();
+
+	find_pcms();
+
+	for (conf = conf_cards; conf; conf = conf->next)
+		if (conf->card < 0)
+			num_missing++;
+
+	num_std_pcm_tests = conf_get_count(default_pcm_config, "test", NULL);
+
+	for (pcm = pcm_list; pcm != NULL; pcm = pcm->next) {
+		num_pcm_tests += num_std_pcm_tests;
+		cfg = pcm->pcm_config;
+		if (cfg == NULL)
+			continue;
+		/* Setting params is reported as a separate test */
+		num_tests = conf_get_count(cfg, "test", NULL) * 2;
+		if (num_tests > 0)
+			num_pcm_tests += num_tests;
+	}
+
+	ksft_set_plan(num_missing + num_pcm_tests);
+
+	for (conf = conf_cards; conf; conf = conf->next)
+		if (conf->card < 0)
+			ksft_test_result_fail("test.missing.%s.%s\n",
+					      conf->filename, conf->config_id);
+
+	for (pcm = pcm_missing; pcm != NULL; pcm = pcm->next) {
+		ksft_test_result(false, "test.missing.%s.%d.%d.%s\n",
+				 pcm->card_name, pcm->device, pcm->subdevice,
+				 snd_pcm_stream_name(pcm->stream));
+	}
+
+	for (card = card_list; card != NULL; card = card->next) {
+		ret = pthread_create(&card->thread, NULL, card_thread, card);
+		if (ret != 0) {
+			ksft_exit_fail_msg("Failed to create card %d thread: %d (%s)\n",
+					   card->card, ret,
+					   strerror(errno));
+		}
+	}
+
+	for (card = card_list; card != NULL; card = card->next) {
+		ret = pthread_join(card->thread, &thread_ret);
+		if (ret != 0) {
+			ksft_exit_fail_msg("Failed to join card %d thread: %d (%s)\n",
+					   card->card, ret,
+					   strerror(errno));
+		}
+	}
+
+	snd_config_delete(global_config);
+	conf_free();
+
+	ksft_exit_pass();
+
+	return 0;
+}
diff --git a/tools/testing/selftests/alsa/pcm-test.conf b/tools/testing/selftests/alsa/pcm-test.conf
new file mode 100644
index 000000000..71bd3f78a
--- /dev/null
+++ b/tools/testing/selftests/alsa/pcm-test.conf
@@ -0,0 +1,63 @@
+pcm.test.time1 {
+	description "8kHz mono large periods"
+	format S16_LE
+	alt_formats [ S32_LE ]
+	rate 8000
+	channels 1
+	period_size 8000
+	buffer_size 32000
+}
+pcm.test.time2 {
+	description "8kHz stereo large periods"
+	format S16_LE
+	alt_formats [ S32_LE ]
+	rate 8000
+	channels 2
+	period_size 8000
+	buffer_size 32000
+}
+pcm.test.time3 {
+	description "44.1kHz stereo large periods"
+	format S16_LE
+	alt_formats [ S32_LE ]
+	rate 44100
+	channels 2
+	period_size 22500
+	buffer_size 192000
+}
+pcm.test.time4 {
+	description "48kHz stereo small periods"
+	format S16_LE
+	alt_formats [ S32_LE ]
+	rate 48000
+	channels 2
+	period_size 512
+	buffer_size 4096
+}
+pcm.test.time5 {
+	description "48kHz stereo large periods"
+	format S16_LE
+	alt_formats [ S32_LE ]
+	rate 48000
+	channels 2
+	period_size 24000
+	buffer_size 192000
+}
+pcm.test.time6 {
+	description "48kHz 6 channel large periods"
+	format S16_LE
+	alt_formats [ S32_LE ]
+	rate 48000
+	channels 2
+	period_size 48000
+	buffer_size 576000
+}
+pcm.test.time7 {
+	description "96kHz stereo large periods"
+	format S16_LE
+	alt_formats [ S32_LE ]
+	rate 96000
+	channels 2
+	period_size 48000
+	buffer_size 192000
+}
diff --git a/tools/testing/selftests/alsa/test-pcmtest-driver.c b/tools/testing/selftests/alsa/test-pcmtest-driver.c
new file mode 100644
index 000000000..95065ef3b
--- /dev/null
+++ b/tools/testing/selftests/alsa/test-pcmtest-driver.c
@@ -0,0 +1,330 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This is the test which covers PCM middle layer data transferring using
+ * the virtual pcm test driver (snd-pcmtest).
+ *
+ * Copyright 2023 Ivan Orlov <ivan.orlov0322@gmail.com>
+ */
+#include <string.h>
+#include <alsa/asoundlib.h>
+#include "kselftest_harness.h"
+
+#define CH_NUM 4
+
+struct pattern_buf {
+	char buf[1024];
+	int len;
+};
+
+struct pattern_buf patterns[CH_NUM];
+
+struct pcmtest_test_params {
+	unsigned long buffer_size;
+	unsigned long period_size;
+	unsigned long channels;
+	unsigned int rate;
+	snd_pcm_access_t access;
+	size_t sec_buf_len;
+	size_t sample_size;
+	int time;
+	snd_pcm_format_t format;
+};
+
+static int read_patterns(void)
+{
+	FILE *fp, *fpl;
+	int i;
+	char pf[64];
+	char plf[64];
+
+	for (i = 0; i < CH_NUM; i++) {
+		sprintf(plf, "/sys/kernel/debug/pcmtest/fill_pattern%d_len", i);
+		fpl = fopen(plf, "r");
+		if (!fpl)
+			return -1;
+		fscanf(fpl, "%u", &patterns[i].len);
+		fclose(fpl);
+
+		sprintf(pf, "/sys/kernel/debug/pcmtest/fill_pattern%d", i);
+		fp = fopen(pf, "r");
+		if (!fp)
+			return -1;
+		fread(patterns[i].buf, 1, patterns[i].len, fp);
+		fclose(fp);
+	}
+
+	return 0;
+}
+
+static int get_test_results(char *debug_name)
+{
+	int result;
+	FILE *f;
+	char fname[128];
+
+	sprintf(fname, "/sys/kernel/debug/pcmtest/%s", debug_name);
+
+	f = fopen(fname, "r");
+	if (!f) {
+		printf("Failed to open file\n");
+		return -1;
+	}
+	fscanf(f, "%d", &result);
+	fclose(f);
+
+	return result;
+}
+
+static size_t get_sec_buf_len(unsigned int rate, unsigned long channels, snd_pcm_format_t format)
+{
+	return rate * channels * snd_pcm_format_physical_width(format) / 8;
+}
+
+static int setup_handle(snd_pcm_t **handle, snd_pcm_sw_params_t *swparams,
+			snd_pcm_hw_params_t *hwparams, struct pcmtest_test_params *params,
+			int card, snd_pcm_stream_t stream)
+{
+	char pcm_name[32];
+	int err;
+
+	sprintf(pcm_name, "hw:%d,0,0", card);
+	err = snd_pcm_open(handle, pcm_name, stream, 0);
+	if (err < 0)
+		return err;
+	snd_pcm_hw_params_any(*handle, hwparams);
+	snd_pcm_hw_params_set_rate_resample(*handle, hwparams, 0);
+	snd_pcm_hw_params_set_access(*handle, hwparams, params->access);
+	snd_pcm_hw_params_set_format(*handle, hwparams, params->format);
+	snd_pcm_hw_params_set_channels(*handle, hwparams, params->channels);
+	snd_pcm_hw_params_set_rate_near(*handle, hwparams, &params->rate, 0);
+	snd_pcm_hw_params_set_period_size_near(*handle, hwparams, &params->period_size, 0);
+	snd_pcm_hw_params_set_buffer_size_near(*handle, hwparams, &params->buffer_size);
+	snd_pcm_hw_params(*handle, hwparams);
+	snd_pcm_sw_params_current(*handle, swparams);
+
+	snd_pcm_hw_params_set_rate_resample(*handle, hwparams, 0);
+	snd_pcm_sw_params_set_avail_min(*handle, swparams, params->period_size);
+	snd_pcm_hw_params_set_buffer_size_near(*handle, hwparams, &params->buffer_size);
+	snd_pcm_hw_params_set_period_size_near(*handle, hwparams, &params->period_size, 0);
+	snd_pcm_sw_params(*handle, swparams);
+	snd_pcm_hw_params(*handle, hwparams);
+
+	return 0;
+}
+
+FIXTURE(pcmtest) {
+	int card;
+	snd_pcm_sw_params_t *swparams;
+	snd_pcm_hw_params_t *hwparams;
+	struct pcmtest_test_params params;
+};
+
+FIXTURE_TEARDOWN(pcmtest) {
+}
+
+FIXTURE_SETUP(pcmtest) {
+	char *card_name;
+	int err;
+
+	if (geteuid())
+		SKIP(return, "This test needs root to run!");
+
+	err = read_patterns();
+	if (err)
+		SKIP(return, "Can't read patterns. Probably, module isn't loaded");
+
+	card_name = malloc(127);
+	ASSERT_NE(card_name, NULL);
+	self->params.buffer_size = 16384;
+	self->params.period_size = 4096;
+	self->params.channels = CH_NUM;
+	self->params.rate = 8000;
+	self->params.access = SND_PCM_ACCESS_RW_INTERLEAVED;
+	self->params.format = SND_PCM_FORMAT_S16_LE;
+	self->card = -1;
+	self->params.sample_size = snd_pcm_format_physical_width(self->params.format) / 8;
+
+	self->params.sec_buf_len = get_sec_buf_len(self->params.rate, self->params.channels,
+						   self->params.format);
+	self->params.time = 4;
+
+	while (snd_card_next(&self->card) >= 0) {
+		if (self->card == -1)
+			break;
+		snd_card_get_name(self->card, &card_name);
+		if (!strcmp(card_name, "PCM-Test"))
+			break;
+	}
+	free(card_name);
+	ASSERT_NE(self->card, -1);
+}
+
+/*
+ * Here we are trying to send the looped monotonically increasing sequence of bytes to the driver.
+ * If our data isn't corrupted, the driver will set the content of 'pc_test' debugfs file to '1'
+ */
+TEST_F(pcmtest, playback) {
+	snd_pcm_t *handle;
+	unsigned char *it;
+	size_t write_res;
+	int test_results;
+	int i, cur_ch, pos_in_ch;
+	void *samples;
+	struct pcmtest_test_params *params = &self->params;
+
+	samples = calloc(self->params.sec_buf_len * self->params.time, 1);
+	ASSERT_NE(samples, NULL);
+
+	snd_pcm_sw_params_alloca(&self->swparams);
+	snd_pcm_hw_params_alloca(&self->hwparams);
+
+	ASSERT_EQ(setup_handle(&handle, self->swparams, self->hwparams, params,
+			       self->card, SND_PCM_STREAM_PLAYBACK), 0);
+	snd_pcm_format_set_silence(params->format, samples,
+				   params->rate * params->channels * params->time);
+	it = samples;
+	for (i = 0; i < self->params.sec_buf_len * params->time; i++) {
+		cur_ch = (i / params->sample_size) % CH_NUM;
+		pos_in_ch = i / params->sample_size / CH_NUM * params->sample_size
+			    + (i % params->sample_size);
+		it[i] = patterns[cur_ch].buf[pos_in_ch % patterns[cur_ch].len];
+	}
+	write_res = snd_pcm_writei(handle, samples, params->rate * params->time);
+	ASSERT_GE(write_res, 0);
+
+	snd_pcm_close(handle);
+	free(samples);
+	test_results = get_test_results("pc_test");
+	ASSERT_EQ(test_results, 1);
+}
+
+/*
+ * Here we test that the virtual alsa driver returns looped and monotonically increasing sequence
+ * of bytes. In the interleaved mode the buffer will contain samples in the following order:
+ * C0, C1, C2, C3, C0, C1, ...
+ */
+TEST_F(pcmtest, capture) {
+	snd_pcm_t *handle;
+	unsigned char *it;
+	size_t read_res;
+	int i, cur_ch, pos_in_ch;
+	void *samples;
+	struct pcmtest_test_params *params = &self->params;
+
+	samples = calloc(self->params.sec_buf_len * self->params.time, 1);
+	ASSERT_NE(samples, NULL);
+
+	snd_pcm_sw_params_alloca(&self->swparams);
+	snd_pcm_hw_params_alloca(&self->hwparams);
+
+	ASSERT_EQ(setup_handle(&handle, self->swparams, self->hwparams,
+			       params, self->card, SND_PCM_STREAM_CAPTURE), 0);
+	snd_pcm_format_set_silence(params->format, samples,
+				   params->rate * params->channels * params->time);
+	read_res = snd_pcm_readi(handle, samples, params->rate * params->time);
+	ASSERT_GE(read_res, 0);
+	snd_pcm_close(handle);
+	it = (unsigned char *)samples;
+	for (i = 0; i < self->params.sec_buf_len * self->params.time; i++) {
+		cur_ch = (i / params->sample_size) % CH_NUM;
+		pos_in_ch = i / params->sample_size / CH_NUM * params->sample_size
+			    + (i % params->sample_size);
+		ASSERT_EQ(it[i], patterns[cur_ch].buf[pos_in_ch % patterns[cur_ch].len]);
+	}
+	free(samples);
+}
+
+// Test capture in the non-interleaved access mode. The are buffers for each recorded channel
+TEST_F(pcmtest, ni_capture) {
+	snd_pcm_t *handle;
+	struct pcmtest_test_params params = self->params;
+	char **chan_samples;
+	size_t i, j, read_res;
+
+	chan_samples = calloc(CH_NUM, sizeof(*chan_samples));
+	ASSERT_NE(chan_samples, NULL);
+
+	snd_pcm_sw_params_alloca(&self->swparams);
+	snd_pcm_hw_params_alloca(&self->hwparams);
+
+	params.access = SND_PCM_ACCESS_RW_NONINTERLEAVED;
+
+	ASSERT_EQ(setup_handle(&handle, self->swparams, self->hwparams,
+			       &params, self->card, SND_PCM_STREAM_CAPTURE), 0);
+
+	for (i = 0; i < CH_NUM; i++)
+		chan_samples[i] = calloc(params.sec_buf_len * params.time, 1);
+
+	for (i = 0; i < 1; i++) {
+		read_res = snd_pcm_readn(handle, (void **)chan_samples, params.rate * params.time);
+		ASSERT_GE(read_res, 0);
+	}
+	snd_pcm_close(handle);
+
+	for (i = 0; i < CH_NUM; i++) {
+		for (j = 0; j < params.rate * params.time; j++)
+			ASSERT_EQ(chan_samples[i][j], patterns[i].buf[j % patterns[i].len]);
+		free(chan_samples[i]);
+	}
+	free(chan_samples);
+}
+
+TEST_F(pcmtest, ni_playback) {
+	snd_pcm_t *handle;
+	struct pcmtest_test_params params = self->params;
+	char **chan_samples;
+	size_t i, j, read_res;
+	int test_res;
+
+	chan_samples = calloc(CH_NUM, sizeof(*chan_samples));
+	ASSERT_NE(chan_samples, NULL);
+
+	snd_pcm_sw_params_alloca(&self->swparams);
+	snd_pcm_hw_params_alloca(&self->hwparams);
+
+	params.access = SND_PCM_ACCESS_RW_NONINTERLEAVED;
+
+	ASSERT_EQ(setup_handle(&handle, self->swparams, self->hwparams,
+			       &params, self->card, SND_PCM_STREAM_PLAYBACK), 0);
+
+	for (i = 0; i < CH_NUM; i++) {
+		chan_samples[i] = calloc(params.sec_buf_len * params.time, 1);
+		for (j = 0; j < params.sec_buf_len * params.time; j++)
+			chan_samples[i][j] = patterns[i].buf[j % patterns[i].len];
+	}
+
+	for (i = 0; i < 1; i++) {
+		read_res = snd_pcm_writen(handle, (void **)chan_samples, params.rate * params.time);
+		ASSERT_GE(read_res, 0);
+	}
+
+	snd_pcm_close(handle);
+	test_res = get_test_results("pc_test");
+	ASSERT_EQ(test_res, 1);
+
+	for (i = 0; i < CH_NUM; i++)
+		free(chan_samples[i]);
+	free(chan_samples);
+}
+
+/*
+ * Here we are testing the custom ioctl definition inside the virtual driver. If it triggers
+ * successfully, the driver sets the content of 'ioctl_test' debugfs file to '1'.
+ */
+TEST_F(pcmtest, reset_ioctl) {
+	snd_pcm_t *handle;
+	int test_res;
+	struct pcmtest_test_params *params = &self->params;
+
+	snd_pcm_sw_params_alloca(&self->swparams);
+	snd_pcm_hw_params_alloca(&self->hwparams);
+
+	ASSERT_EQ(setup_handle(&handle, self->swparams, self->hwparams, params,
+			       self->card, SND_PCM_STREAM_CAPTURE), 0);
+	snd_pcm_reset(handle);
+	test_res = get_test_results("ioctl_test");
+	ASSERT_EQ(test_res, 1);
+	snd_pcm_close(handle);
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/alsa/utimer-test.c b/tools/testing/selftests/alsa/utimer-test.c
new file mode 100644
index 000000000..1a9ff010c
--- /dev/null
+++ b/tools/testing/selftests/alsa/utimer-test.c
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * This test covers the functionality of userspace-driven ALSA timers. Such timers
+ * are purely virtual (so they don't directly depend on the hardware), and they could be
+ * created and triggered by userspace applications.
+ *
+ * Author: Ivan Orlov <ivan.orlov0322@gmail.com>
+ */
+#include "kselftest_harness.h"
+#include <sound/asound.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <sys/ioctl.h>
+#include <stdlib.h>
+#include <pthread.h>
+#include <string.h>
+#include <errno.h>
+
+#define FRAME_RATE 8000
+#define PERIOD_SIZE 4410
+#define UTIMER_DEFAULT_ID -1
+#define UTIMER_DEFAULT_FD -1
+#define NANO 1000000000ULL
+#define TICKS_COUNT 10
+#define TICKS_RECORDING_DELTA 5
+#define TIMER_OUTPUT_BUF_LEN 1024
+#define TIMER_FREQ_SEC 1
+#define RESULT_PREFIX_LEN strlen("Total ticks count: ")
+
+enum timer_app_event {
+	TIMER_APP_STARTED,
+	TIMER_APP_RESULT,
+	TIMER_NO_EVENT,
+};
+
+FIXTURE(timer_f) {
+	struct snd_timer_uinfo *utimer_info;
+};
+
+FIXTURE_SETUP(timer_f) {
+	int timer_dev_fd;
+
+	if (geteuid())
+		SKIP(return, "This test needs root to run!");
+
+	self->utimer_info = calloc(1, sizeof(*self->utimer_info));
+	ASSERT_NE(NULL, self->utimer_info);
+
+	/* Resolution is the time the period of frames takes in nanoseconds */
+	self->utimer_info->resolution = (NANO / FRAME_RATE * PERIOD_SIZE);
+
+	timer_dev_fd = open("/dev/snd/timer", O_RDONLY);
+	ASSERT_GE(timer_dev_fd, 0);
+
+	if (ioctl(timer_dev_fd, SNDRV_TIMER_IOCTL_CREATE, self->utimer_info) < 0) {
+		int err = errno;
+
+		close(timer_dev_fd);
+		if (err == ENOTTY || err == ENXIO)
+			SKIP(return, "CONFIG_SND_UTIMER not enabled");
+		ASSERT_EQ(err, 0);
+	}
+	ASSERT_GE(self->utimer_info->fd, 0);
+
+	close(timer_dev_fd);
+}
+
+FIXTURE_TEARDOWN(timer_f) {
+	close(self->utimer_info->fd);
+	free(self->utimer_info);
+}
+
+static void *ticking_func(void *data)
+{
+	int i;
+	int *fd = (int *)data;
+
+	for (i = 0; i < TICKS_COUNT; i++) {
+		/* Well, trigger the timer! */
+		ioctl(*fd, SNDRV_TIMER_IOCTL_TRIGGER, NULL);
+		sleep(TIMER_FREQ_SEC);
+	}
+
+	return NULL;
+}
+
+static enum timer_app_event parse_timer_output(const char *s)
+{
+	if (strstr(s, "Timer has started"))
+		return TIMER_APP_STARTED;
+	if (strstr(s, "Total ticks count"))
+		return TIMER_APP_RESULT;
+
+	return TIMER_NO_EVENT;
+}
+
+static int parse_timer_result(const char *s)
+{
+	char *end;
+	long d;
+
+	d = strtol(s + RESULT_PREFIX_LEN, &end, 10);
+	if (end == s + RESULT_PREFIX_LEN)
+		return -1;
+
+	return d;
+}
+
+/*
+ * This test triggers the timer and counts ticks at the same time. The amount
+ * of the timer trigger calls should be equal to the amount of ticks received.
+ */
+TEST_F(timer_f, utimer) {
+	char command[64];
+	pthread_t ticking_thread;
+	int total_ticks = 0;
+	FILE *rfp;
+	char *buf = malloc(TIMER_OUTPUT_BUF_LEN);
+
+	ASSERT_NE(buf, NULL);
+
+	/* The timeout should be the ticks interval * count of ticks + some delta */
+	sprintf(command, "./global-timer %d %d %d", SNDRV_TIMER_GLOBAL_UDRIVEN,
+		self->utimer_info->id, TICKS_COUNT * TIMER_FREQ_SEC + TICKS_RECORDING_DELTA);
+
+	rfp = popen(command, "r");
+	while (fgets(buf, TIMER_OUTPUT_BUF_LEN, rfp)) {
+		buf[TIMER_OUTPUT_BUF_LEN - 1] = 0;
+		switch (parse_timer_output(buf)) {
+		case TIMER_APP_STARTED:
+			/* global-timer waits for timer to trigger, so start the ticking thread */
+			pthread_create(&ticking_thread, NULL, ticking_func,
+				       &self->utimer_info->fd);
+			break;
+		case TIMER_APP_RESULT:
+			total_ticks = parse_timer_result(buf);
+			break;
+		case TIMER_NO_EVENT:
+			break;
+		}
+	}
+	pthread_join(ticking_thread, NULL);
+	ASSERT_EQ(total_ticks, TICKS_COUNT);
+	pclose(rfp);
+	free(buf);
+}
+
+TEST(wrong_timers_test) {
+	int timer_dev_fd;
+	int utimer_fd;
+	struct snd_timer_uinfo wrong_timer = {
+		.resolution = 0,
+		.id = UTIMER_DEFAULT_ID,
+		.fd = UTIMER_DEFAULT_FD,
+	};
+
+	timer_dev_fd = open("/dev/snd/timer", O_RDONLY);
+	ASSERT_GE(timer_dev_fd, 0);
+
+	utimer_fd = ioctl(timer_dev_fd, SNDRV_TIMER_IOCTL_CREATE, &wrong_timer);
+	ASSERT_LT(utimer_fd, 0);
+	/* Check that id was not updated */
+	ASSERT_EQ(wrong_timer.id, UTIMER_DEFAULT_ID);
+
+	/* Test the NULL as an argument is processed correctly */
+	ASSERT_LT(ioctl(timer_dev_fd, SNDRV_TIMER_IOCTL_CREATE, NULL), 0);
+
+	close(timer_dev_fd);
+}
+
+TEST_HARNESS_MAIN