ASoC: SOF: Make creation of machine device from SOF core optional

Currently, SOF probes machine drivers by creating a platform device
and passing the machine description as private data.

This is driven by the ACPI restrictions. Ideally, ACPI tables
should contain the description for the machine driver. This is
not possible because ACPI tables are frozen and used on multiple
OS-es (e.g Windows).

In the case of Device Tree we don't have this restriction, so we
choose to probe the machine drivers by creating a DT node as is
the standard ALSA way.

This patch makes the probing of machine drivers from SOF
core optional allowing for Device Tree platforms to decouple
the SOF core from machine driver probing.

Along with this, it also consolidates the machine driver selection
for Intel platforms by defining optional ops for selecting the machine
driver based on the ACPI match for HDA and non-HDA platforms and
setting the mach params.

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191204211556.12671-11-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 80 insertions, 0 deletions

diff --git a/sound/soc/sof/sof-audio.c b/sound/soc/sof/sof-audio.c
index bf99d040c9c1..9c3851bfe788 100644
--- a/sound/soc/sof/sof-audio.c
+++ b/sound/soc/sof/sof-audio.c
@@ -360,3 +360,83 @@ struct snd_sof_dai *snd_sof_find_dai(struct snd_soc_component *scomp,
 	return NULL;
 }
 
+/*
+ * SOF Driver enumeration.
+ */
+int sof_machine_check(struct snd_sof_dev *sdev)
+{
+	struct snd_sof_pdata *sof_pdata = sdev->pdata;
+	const struct sof_dev_desc *desc = sof_pdata->desc;
+	struct snd_soc_acpi_mach *mach;
+	int ret;
+
+	/* force nocodec mode */
+#if IS_ENABLED(CONFIG_SND_SOC_SOF_FORCE_NOCODEC_MODE)
+		dev_warn(sdev->dev, "Force to use nocodec mode\n");
+		goto nocodec;
+#endif
+
+	/* find machine */
+	snd_sof_machine_select(sdev);
+	if (sof_pdata->machine) {
+		snd_sof_set_mach_params(sof_pdata->machine, sdev->dev);
+		return 0;
+	}
+
+#if !IS_ENABLED(CONFIG_SND_SOC_SOF_NOCODEC)
+	dev_err(sdev->dev, "error: no matching ASoC machine driver found - aborting probe\n");
+	return -ENODEV;
+#endif
+#if IS_ENABLED(CONFIG_SND_SOC_SOF_FORCE_NOCODEC_MODE)
+nocodec:
+#endif
+	/* select nocodec mode */
+	dev_warn(sdev->dev, "Using nocodec machine driver\n");
+	mach = devm_kzalloc(sdev->dev, sizeof(*mach), GFP_KERNEL);
+	if (!mach)
+		return -ENOMEM;
+
+	ret = sof_nocodec_setup(sdev->dev, sof_pdata, mach, desc, desc->ops);
+	if (ret < 0)
+		return ret;
+
+	sof_pdata->machine = mach;
+	snd_sof_set_mach_params(sof_pdata->machine, sdev->dev);
+
+	return 0;
+}
+EXPORT_SYMBOL(sof_machine_check);
+
+int sof_machine_register(struct snd_sof_dev *sdev, void *pdata)
+{
+	struct snd_sof_pdata *plat_data = (struct snd_sof_pdata *)pdata;
+	const char *drv_name;
+	const void *mach;
+	int size;
+
+	drv_name = plat_data->machine->drv_name;
+	mach = (const void *)plat_data->machine;
+	size = sizeof(*plat_data->machine);
+
+	/* register machine driver, pass machine info as pdata */
+	plat_data->pdev_mach =
+		platform_device_register_data(sdev->dev, drv_name,
+					      PLATFORM_DEVID_NONE, mach, size);
+	if (IS_ERR(plat_data->pdev_mach))
+		return PTR_ERR(plat_data->pdev_mach);
+
+	dev_dbg(sdev->dev, "created machine %s\n",
+		dev_name(&plat_data->pdev_mach->dev));
+
+	return 0;
+}
+EXPORT_SYMBOL(sof_machine_register);
+
+void sof_machine_unregister(struct snd_sof_dev *sdev, void *pdata)
+{
+	struct snd_sof_pdata *plat_data = (struct snd_sof_pdata *)pdata;
+
+	if (!IS_ERR_OR_NULL(plat_data->pdev_mach))
+		platform_device_unregister(plat_data->pdev_mach);
+}
+EXPORT_SYMBOL(sof_machine_unregister);