ASoC: soc-utils: Add kunit test for snd_soc_tdm_params_to_bclk()

Create a new kunit test for soc-utils and use it to test
snd_soc_tdm_params_to_bclk().

The test uses a table of values to avoid the possibility that an
on-the-fly generator contains the same algorithmic error as the
function-under-test and so fails to detect a bug.

There is no need to test every possible combination of values.
Enough test cases are included to give confidence that the function
is producing the correct results.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20220405135419.1230088-4-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

3 files changed, 199 insertions, 1 deletions

diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig
index 5dcf77af07af..7d4747b6bab2 100644
--- a/sound/soc/Kconfig
+++ b/sound/soc/Kconfig
@@ -14,7 +14,7 @@ menuconfig SND_SOC
 
 	  If you want ASoC support, you should say Y here and also to the
 	  specific driver for your SoC platform below.
-	  
+
 	  ASoC provides power efficient ALSA support for embedded battery powered
 	  SoC based systems like PDA's, Phones and Personal Media Players.
 
@@ -55,6 +55,13 @@ config SND_SOC_TOPOLOGY_KUNIT_TEST
 	  userspace applications such as pulseaudio, to prevent unnecessary
 	  problems.
 
+config SND_SOC_UTILS_KUNIT_TEST
+	tristate "KUnit tests for SoC utils"
+	depends on KUNIT
+	default KUNIT_ALL_TESTS
+	help
+	  If you want to perform tests on ALSA SoC utils library say Y here.
+
 config SND_SOC_ACPI
 	tristate
 
diff --git a/sound/soc/Makefile b/sound/soc/Makefile
index a7b37c06dc43..d4528962ac34 100644
--- a/sound/soc/Makefile
+++ b/sound/soc/Makefile
@@ -12,6 +12,11 @@ ifneq ($(CONFIG_SND_SOC_TOPOLOGY_KUNIT_TEST),)
 obj-$(CONFIG_SND_SOC_TOPOLOGY_KUNIT_TEST) := soc-topology-test.o
 endif
 
+ifneq ($(CONFIG_SND_SOC_UTILS_KUNIT_TEST),)
+# snd-soc-test-objs := soc-utils-test.o
+obj-$(CONFIG_SND_SOC_UTILS_KUNIT_TEST) := soc-utils-test.o
+endif
+
 ifneq ($(CONFIG_SND_SOC_GENERIC_DMAENGINE_PCM),)
 snd-soc-core-objs += soc-generic-dmaengine-pcm.o
 endif
diff --git a/sound/soc/soc-utils-test.c b/sound/soc/soc-utils-test.c
new file mode 100644
index 000000000000..5ad8e23af49a
--- /dev/null
+++ b/sound/soc/soc-utils-test.c
@@ -0,0 +1,186 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2022 Cirrus Logic, Inc. and
+//                    Cirrus Logic International Semiconductor Ltd.
+
+#include <kunit/test.h>
+#include <linux/module.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <uapi/sound/asound.h>
+
+static const struct {
+	u32 rate;
+	snd_pcm_format_t fmt;
+	u8 channels;
+	u8 tdm_width;
+	u8 tdm_slots;
+	u8 slot_multiple;
+	u32 bclk;
+} tdm_params_to_bclk_cases[] = {
+	/* rate		fmt	   channels tdm_width tdm_slots slot_multiple bclk */
+
+	/* From params only */
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	0,	0,	  128000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	0,	0,	  256000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 1,	0,	0,	0,	  192000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 2,	0,	0,	0,	  384000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	0,	0,	  256000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	0,	0,	  512000 },
+	{  44100,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	0,	0,	  705600 },
+	{  44100,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	0,	0,	 1411200 },
+	{  44100,  SNDRV_PCM_FORMAT_S24_LE, 1,	0,	0,	0,	 1058400 },
+	{  44100,  SNDRV_PCM_FORMAT_S24_LE, 2,	0,	0,	0,	 2116800 },
+	{  44100,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	0,	0,	 1411200 },
+	{  44100,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	0,	0,	 2822400 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	0,	0,	 6144000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	0,	0,	12288000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S24_LE, 1,	0,	0,	0,	 9216000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S24_LE, 2,	0,	0,	0,	18432000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	0,	0,	12288000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	0,	0,	24576000 },
+
+	/* I2S from params */
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	0,	2,	  256000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	0,	2,	  256000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 1,	0,	0,	2,	  384000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 2,	0,	0,	2,	  384000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	0,	2,	  512000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	0,	2,	  512000 },
+	{  44100,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	0,	2,	 1411200 },
+	{  44100,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	0,	2,	 1411200 },
+	{  44100,  SNDRV_PCM_FORMAT_S24_LE, 1,	0,	0,	2,	 2116800 },
+	{  44100,  SNDRV_PCM_FORMAT_S24_LE, 2,	0,	0,	2,	 2116800 },
+	{  44100,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	0,	2,	 2822400 },
+	{  44100,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	0,	2,	 2822400 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	0,	2,	12288000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	0,	2,	12288000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S24_LE, 1,	0,	0,	2,	18432000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S24_LE, 2,	0,	0,	2,	18432000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	0,	2,	24576000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	0,	2,	24576000 },
+
+	/* Fixed 8-slot TDM, other values from params */
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	8,	0,	 1024000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	8,	0,	 1024000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 3,	0,	8,	0,	 1024000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 4,	0,	8,	0,	 1024000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	8,	0,	 2048000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	8,	0,	 2048000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 3,	0,	8,	0,	 2048000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 4,	0,	8,	0,	 2048000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 1,	0,	8,	0,	49152000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 2,	0,	8,	0,	49152000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 3,	0,	8,	0,	49152000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 4,	0,	8,	0,	49152000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 1,	0,	8,	0,	98304000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 2,	0,	8,	0,	98304000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 3,	0,	8,	0,	98304000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 4,	0,	8,	0,	98304000 },
+
+	/* Fixed 32-bit TDM, other values from params */
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 1,	32,	0,	0,	  256000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 2,	32,	0,	0,	  512000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 3,	32,	0,	0,	  768000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 4,	32,	0,	0,	 1024000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 1,	32,	0,	0,	  256000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 2,	32,	0,	0,	  512000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 3,	32,	0,	0,	  768000 },
+	{   8000,  SNDRV_PCM_FORMAT_S32_LE, 4,	32,	0,	0,	 1024000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 1,	32,	0,	0,	12288000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 2,	32,	0,	0,	24576000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 3,	32,	0,	0,	36864000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S16_LE, 4,	32,	0,	0,	49152000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 1,	32,	0,	0,	12288000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 2,	32,	0,	0,	24576000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 3,	32,	0,	0,	36864000 },
+	{ 384000,  SNDRV_PCM_FORMAT_S32_LE, 4,	32,	0,	0,	49152000 },
+
+	/* Fixed 6-slot 24-bit TDM, other values from params */
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 1,	24,	6,	0,	 1152000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 2,	24,	6,	0,	 1152000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 3,	24,	6,	0,	 1152000 },
+	{   8000,  SNDRV_PCM_FORMAT_S16_LE, 4,	24,	6,	0,	 1152000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 1,	24,	6,	0,	 1152000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 2,	24,	6,	0,	 1152000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 3,	24,	6,	0,	 1152000 },
+	{   8000,  SNDRV_PCM_FORMAT_S24_LE, 4,	24,	6,	0,	 1152000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S16_LE, 1,	24,	6,	0,	27648000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S16_LE, 2,	24,	6,	0,	27648000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S16_LE, 3,	24,	6,	0,	27648000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S16_LE, 4,	24,	6,	0,	27648000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S24_LE, 1,	24,	6,	0,	27648000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S24_LE, 2,	24,	6,	0,	27648000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S24_LE, 3,	24,	6,	0,	27648000 },
+	{ 192000,  SNDRV_PCM_FORMAT_S24_LE, 4,	24,	6,	0,	27648000 },
+};
+
+static void test_tdm_params_to_bclk_one(struct kunit *test,
+					unsigned int rate, snd_pcm_format_t fmt,
+					unsigned int channels,
+					unsigned int tdm_width, unsigned int tdm_slots,
+					unsigned int slot_multiple,
+					unsigned int expected_bclk)
+{
+	struct snd_pcm_hw_params params;
+	int got_bclk;
+
+	_snd_pcm_hw_params_any(&params);
+	snd_mask_none(hw_param_mask(&params, SNDRV_PCM_HW_PARAM_FORMAT));
+	hw_param_interval(&params, SNDRV_PCM_HW_PARAM_RATE)->min = rate;
+	hw_param_interval(&params, SNDRV_PCM_HW_PARAM_RATE)->max = rate;
+	hw_param_interval(&params, SNDRV_PCM_HW_PARAM_CHANNELS)->min = channels;
+	hw_param_interval(&params, SNDRV_PCM_HW_PARAM_CHANNELS)->max = channels;
+	params_set_format(&params, fmt);
+
+	got_bclk = snd_soc_tdm_params_to_bclk(&params, tdm_width, tdm_slots, slot_multiple);
+	pr_debug("%s: r=%u sb=%u ch=%u tw=%u ts=%u sm=%u expected=%u got=%d\n",
+		 __func__,
+		 rate, params_width(&params), channels, tdm_width, tdm_slots, slot_multiple,
+		 expected_bclk, got_bclk);
+	KUNIT_ASSERT_EQ(test, expected_bclk, (unsigned int)got_bclk);
+}
+
+static void test_tdm_params_to_bclk(struct kunit *test)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(tdm_params_to_bclk_cases); ++i) {
+		test_tdm_params_to_bclk_one(test,
+					    tdm_params_to_bclk_cases[i].rate,
+					    tdm_params_to_bclk_cases[i].fmt,
+					    tdm_params_to_bclk_cases[i].channels,
+					    tdm_params_to_bclk_cases[i].tdm_width,
+					    tdm_params_to_bclk_cases[i].tdm_slots,
+					    tdm_params_to_bclk_cases[i].slot_multiple,
+					    tdm_params_to_bclk_cases[i].bclk);
+
+		if (tdm_params_to_bclk_cases[i].slot_multiple > 0)
+			continue;
+
+		/* Slot multiple 1 should have the same effect as multiple 0 */
+		test_tdm_params_to_bclk_one(test,
+					    tdm_params_to_bclk_cases[i].rate,
+					    tdm_params_to_bclk_cases[i].fmt,
+					    tdm_params_to_bclk_cases[i].channels,
+					    tdm_params_to_bclk_cases[i].tdm_width,
+					    tdm_params_to_bclk_cases[i].tdm_slots,
+					    1,
+					    tdm_params_to_bclk_cases[i].bclk);
+	}
+}
+
+static struct kunit_case soc_utils_test_cases[] = {
+	KUNIT_CASE(test_tdm_params_to_bclk),
+	{}
+};
+
+static struct kunit_suite soc_utils_test_suite = {
+	.name = "soc-utils",
+	.test_cases = soc_utils_test_cases,
+};
+
+kunit_test_suites(&soc_utils_test_suite);
+
+MODULE_DESCRIPTION("ASoC soc-utils kunit test");
+MODULE_LICENSE("GPL");