base: soc: populate machine name in soc_device_register if empty

Several SoC drivers use the same of-based mechanism to populate the machine
name. Therefore move this to the core and try to populate the machine name
in soc_device_register if it's not set yet.
Signed-off-by: NHeiner Kallweit <hkallweit1@gmail.com>
Acked-by: NMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/6dbdf458-9f46-613e-de58-b4a56a6cdd9f@gmail.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/base/soc.c

@@ -7,6 +7,7 @@
 
 #include <linux/sysfs.h>
 #include <linux/init.h>
+#include <linux/of.h>
 #include <linux/stat.h>
 #include <linux/slab.h>
 #include <linux/idr.h>
@@ -110,6 +111,18 @@ static void soc_release(struct device *dev)
 	kfree(soc_dev);
 }
 
+static void soc_device_get_machine(struct soc_device_attribute *soc_dev_attr)
+{
+	struct device_node *np;
+
+	if (soc_dev_attr->machine)
+		return;
+
+	np = of_find_node_by_path("/");
+	of_property_read_string(np, "model", &soc_dev_attr->machine);
+	of_node_put(np);
+}
+
 static struct soc_device_attribute *early_soc_dev_attr;
 
 struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr)
@@ -118,6 +131,8 @@ struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr
 	const struct attribute_group **soc_attr_groups;
 	int ret;
 
+	soc_device_get_machine(soc_dev_attr);
+
 	if (!soc_bus_registered) {
 		if (early_soc_dev_attr)
 			return ERR_PTR(-EBUSY);