v4.19.13 snapshot.
diff --git a/sound/aoa/soundbus/sysfs.c b/sound/aoa/soundbus/sysfs.c
new file mode 100644
index 0000000..81da020
--- /dev/null
+++ b/sound/aoa/soundbus/sysfs.c
@@ -0,0 +1,46 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/stat.h>
+/* FIX UP */
+#include "soundbus.h"
+
+#define soundbus_config_of_attr(field, format_string)			\
+static ssize_t								\
+field##_show (struct device *dev, struct device_attribute *attr,	\
+              char *buf)						\
+{									\
+	struct soundbus_dev *mdev = to_soundbus_device (dev);		\
+	return sprintf (buf, format_string, mdev->ofdev.dev.of_node->field); \
+}
+
+static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct soundbus_dev *sdev = to_soundbus_device(dev);
+	struct platform_device *of = &sdev->ofdev;
+	int length;
+
+	if (*sdev->modalias) {
+		strlcpy(buf, sdev->modalias, sizeof(sdev->modalias) + 1);
+		strcat(buf, "\n");
+		length = strlen(buf);
+	} else {
+		length = sprintf(buf, "of:N%sT%s\n",
+				 of->dev.of_node->name, of->dev.of_node->type);
+	}
+
+	return length;
+}
+static DEVICE_ATTR_RO(modalias);
+
+soundbus_config_of_attr (name, "%s\n");
+static DEVICE_ATTR_RO(name);
+soundbus_config_of_attr (type, "%s\n");
+static DEVICE_ATTR_RO(type);
+
+struct attribute *soundbus_dev_attrs[] = {
+	&dev_attr_name.attr,
+	&dev_attr_type.attr,
+	&dev_attr_modalias.attr,
+	NULL,
+};