Merge tag 'soc-device-match-tag1' of...

Merge tag 'soc-device-match-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers into next/drivers

Pull "soc_device_match() interface for matching against soc_bus attributes"
from Geert Uytterhoeven:

This provides core infrastructure as a dependency for several users
(Freescale/NXP, Samsung, Renesas).

Its core parts have been acked by Greg, and the fixes by Arnd and/or
Greg (the last fix only received an informal ack, that's why I hadn't
added the ack).

This has already been pulled by Ulf, and is present in mmc/next, as a
dependency for a Freescale/NXP driver update.

* tag 'soc-device-match-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers:
  base: soc: Provide a dummy implementation of soc_device_match()
  base: soc: Check for NULL SoC device attributes
  base: soc: Introduce soc_device_match() interface
  base: soc: Early register bus when needed

drivers/base/Kconfig

@@ -235,6 +235,7 @@ config GENERIC_CPU_AUTOPROBE
 
 config SOC_BUS
 	bool
+	select GLOB
 
 source "drivers/base/regmap/Kconfig"
 

drivers/base/soc.c

@@ -13,6 +13,7 @@
 #include <linux/spinlock.h>
 #include <linux/sys_soc.h>
 #include <linux/err.h>
+#include <linux/glob.h>
 
 static DEFINE_IDA(soc_ida);
 
@@ -113,6 +114,12 @@ struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr
 	struct soc_device *soc_dev;
 	int ret;
 
+	if (!soc_bus_type.p) {
+		ret = bus_register(&soc_bus_type);
+		if (ret)
+			goto out1;
+	}
+
 	soc_dev = kzalloc(sizeof(*soc_dev), GFP_KERNEL);
 	if (!soc_dev) {
 		ret = -ENOMEM;
@@ -156,6 +163,78 @@ void soc_device_unregister(struct soc_device *soc_dev)
 
 static int __init soc_bus_register(void)
 {
+	if (soc_bus_type.p)
+		return 0;
+
 	return bus_register(&soc_bus_type);
 }
 core_initcall(soc_bus_register);
+
+static int soc_device_match_one(struct device *dev, void *arg)
+{
+	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev);
+	const struct soc_device_attribute *match = arg;
+
+	if (match->machine &&
+	    (!soc_dev->attr->machine ||
+	     !glob_match(match->machine, soc_dev->attr->machine)))
+		return 0;
+
+	if (match->family &&
+	    (!soc_dev->attr->family ||
+	     !glob_match(match->family, soc_dev->attr->family)))
+		return 0;
+
+	if (match->revision &&
+	    (!soc_dev->attr->revision ||
+	     !glob_match(match->revision, soc_dev->attr->revision)))
+		return 0;
+
+	if (match->soc_id &&
+	    (!soc_dev->attr->soc_id ||
+	     !glob_match(match->soc_id, soc_dev->attr->soc_id)))
+		return 0;
+
+	return 1;
+}
+
+/*
+ * soc_device_match - identify the SoC in the machine
+ * @matches: zero-terminated array of possible matches
+ *
+ * returns the first matching entry of the argument array, or NULL
+ * if none of them match.
+ *
+ * This function is meant as a helper in place of of_match_node()
+ * in cases where either no device tree is available or the information
+ * in a device node is insufficient to identify a particular variant
+ * by its compatible strings or other properties. For new devices,
+ * the DT binding should always provide unique compatible strings
+ * that allow the use of of_match_node() instead.
+ *
+ * The calling function can use the .data entry of the
+ * soc_device_attribute to pass a structure or function pointer for
+ * each entry.
+ */
+const struct soc_device_attribute *soc_device_match(
+	const struct soc_device_attribute *matches)
+{
+	int ret = 0;
+
+	if (!matches)
+		return NULL;
+
+	while (!ret) {
+		if (!(matches->machine || matches->family ||
+		      matches->revision || matches->soc_id))
+			break;
+		ret = bus_for_each_dev(&soc_bus_type, NULL, (void *)matches,
+				       soc_device_match_one);
+		if (!ret)
+			matches++;
+		else
+			return matches;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(soc_device_match);

include/linux/sys_soc.h

@@ -13,6 +13,7 @@ struct soc_device_attribute {
 	const char *family;
 	const char *revision;
 	const char *soc_id;
+	const void *data;
 };
 
 /**
@@ -34,4 +35,12 @@ void soc_device_unregister(struct soc_device *soc_dev);
  */
 struct device *soc_device_to_device(struct soc_device *soc);
 
+#ifdef CONFIG_SOC_BUS
+const struct soc_device_attribute *soc_device_match(
+	const struct soc_device_attribute *matches);
+#else
+static inline const struct soc_device_attribute *soc_device_match(
+	const struct soc_device_attribute *matches) { return NULL; }
+#endif
+
 #endif /* __SOC_BUS_H */