ASoC: Intel: avs: Add probe machine board

Stub machine board driver with no custom DAPM routes and single FE DAI
link for userspace to interact with.

Signed-off-by: Cezary Rojewski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Mark Brown <[email protected]>

Author: crojewsk-intel

sound/soc/intel/avs/board_selection.c

@@ -291,6 +291,33 @@ static void board_pdev_unregister(void *data)
 	platform_device_unregister(data);
 }
 
+static int __maybe_unused avs_register_probe_board(struct avs_dev *adev)
+{
+	struct platform_device *board;
+	struct snd_soc_acpi_mach mach = {{0}};
+	int ret;
+
+	ret = avs_probe_platform_register(adev, "probe-platform");
+	if (ret < 0)
+		return ret;
+
+	mach.mach_params.platform = "probe-platform";
+
+	board = platform_device_register_data(NULL, "avs_probe_mb", PLATFORM_DEVID_NONE,
+					      (const void *)&mach, sizeof(mach));
+	if (IS_ERR(board)) {
+		dev_err(adev->dev, "probe board register failed\n");
+		return PTR_ERR(board);
+	}
+
+	ret = devm_add_action(adev->dev, board_pdev_unregister, board);
+	if (ret < 0) {
+		platform_device_unregister(board);
+		return ret;
+	}
+	return 0;
+}
+
 static int avs_register_dmic_board(struct avs_dev *adev)
 {
 	struct platform_device *codec, *board;
@@ -500,6 +527,12 @@ int avs_register_all_boards(struct avs_dev *adev)
 {
 	int ret;
 
+#ifdef CONFIG_DEBUG_FS
+	ret = avs_register_probe_board(adev);
+	if (ret < 0)
+		dev_warn(adev->dev, "enumerate PROBE endpoints failed: %d\n", ret);
+#endif
+
 	ret = avs_register_dmic_board(adev);
 	if (ret < 0)
 		dev_warn(adev->dev, "enumerate DMIC endpoints failed: %d\n",

sound/soc/intel/avs/boards/Kconfig

@@ -77,6 +77,14 @@ config SND_SOC_INTEL_AVS_MACH_NAU8825
 	   Say Y or m if you have such a device. This is a recommended option.
 	   If unsure select "N".
 
+config SND_SOC_INTEL_AVS_MACH_PROBE
+	tristate "Probing (data) board"
+	depends on DEBUG_FS
+	select SND_HWDEP
+	help
+	   This adds support for data probing board which can be used to
+	   gather data from runtime stream over compress operations.
+
 config SND_SOC_INTEL_AVS_MACH_RT274
 	tristate "rt274 in I2S mode"
 	depends on I2C

sound/soc/intel/avs/boards/Makefile

@@ -8,6 +8,7 @@ snd-soc-avs-max98927-objs := max98927.o
 snd-soc-avs-max98357a-objs := max98357a.o
 snd-soc-avs-max98373-objs := max98373.o
 snd-soc-avs-nau8825-objs := nau8825.o
+snd-soc-avs-probe-objs := probe.o
 snd-soc-avs-rt274-objs := rt274.o
 snd-soc-avs-rt286-objs := rt286.o
 snd-soc-avs-rt298-objs := rt298.o
@@ -22,6 +23,7 @@ obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_MAX98927) += snd-soc-avs-max98927.o
 obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_MAX98357A) += snd-soc-avs-max98357a.o
 obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_MAX98373) += snd-soc-avs-max98373.o
 obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_NAU8825) += snd-soc-avs-nau8825.o
+obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_PROBE) += snd-soc-avs-probe.o
 obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_RT274) += snd-soc-avs-rt274.o
 obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_RT286) += snd-soc-avs-rt286.o
 obj-$(CONFIG_SND_SOC_INTEL_AVS_MACH_RT298) += snd-soc-avs-rt298.o

sound/soc/intel/avs/boards/probe.c

@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// Copyright(c) 2021-2022 Intel Corporation. All rights reserved.
+//
+// Authors: Cezary Rojewski <[email protected]>
+//          Amadeusz Slawinski <[email protected]>
+//
+
+#include <linux/device.h>
+#include <linux/module.h>
+#include <sound/soc.h>
+#include <sound/soc-acpi.h>
+
+SND_SOC_DAILINK_DEF(dummy, DAILINK_COMP_ARRAY(COMP_DUMMY()));
+SND_SOC_DAILINK_DEF(probe_cp, DAILINK_COMP_ARRAY(COMP_CPU("Probe Extraction CPU DAI")));
+SND_SOC_DAILINK_DEF(platform, DAILINK_COMP_ARRAY(COMP_PLATFORM("probe-platform")));
+
+static struct snd_soc_dai_link probe_mb_dai_links[] = {
+	{
+		.name = "Compress Probe Capture",
+		.nonatomic = 1,
+		SND_SOC_DAILINK_REG(probe_cp, dummy, platform),
+	},
+};
+
+static int avs_probe_mb_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct snd_soc_acpi_mach *mach;
+	struct snd_soc_card *card;
+	int ret;
+
+	mach = dev_get_platdata(dev);
+
+	card = devm_kzalloc(dev, sizeof(*card), GFP_KERNEL);
+	if (!card)
+		return -ENOMEM;
+
+	card->name = "avs_probe_mb";
+	card->dev = dev;
+	card->owner = THIS_MODULE;
+	card->dai_link = probe_mb_dai_links;
+	card->num_links = ARRAY_SIZE(probe_mb_dai_links);
+	card->fully_routed = true;
+
+	ret = snd_soc_fixup_dai_links_platform_name(card, mach->mach_params.platform);
+	if (ret)
+		return ret;
+
+	return devm_snd_soc_register_card(dev, card);
+}
+
+static struct platform_driver avs_probe_mb_driver = {
+	.probe = avs_probe_mb_probe,
+	.driver = {
+		.name = "avs_probe_mb",
+		.pm = &snd_soc_pm_ops,
+	},
+};
+
+module_platform_driver(avs_probe_mb_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:avs_probe_mb");