MIPS: Create a helper function for DT setup

A couple of platforms register two buses and call of_platform_populate().
Move this into a common function to reduce duplication.

Signed-off-by: Kevin Cernekee <cernekee@gmail.com>
Cc: f.fainelli@gmail.com
Cc: mbizon@freebox.fr
Cc: jogo@openwrt.org
Cc: jfraser@broadcom.com
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8167/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/include/asm/prom.h

@@ -22,6 +22,7 @@ extern void device_tree_init(void);
 struct boot_param_header;
 
 extern void __dt_setup_arch(void *bph);
+extern int __dt_register_buses(const char *bus0, const char *bus1);
 
 #define dt_setup_arch(sym)						\
 ({									\

arch/mips/kernel/prom.c

@@ -16,6 +16,7 @@
 #include <linux/debugfs.h>
 #include <linux/of.h>
 #include <linux/of_fdt.h>
+#include <linux/of_platform.h>
 
 #include <asm/page.h>
 #include <asm/prom.h>
@@ -54,4 +55,21 @@ void __init __dt_setup_arch(void *bph)
 
 	mips_set_machine_name(of_flat_dt_get_machine_name());
 }
+
+int __init __dt_register_buses(const char *bus0, const char *bus1)
+{
+	static struct of_device_id of_ids[3];
+
+	if (!of_have_populated_dt())
+		panic("device tree not present");
+
+	strlcpy(of_ids[0].compatible, bus0, sizeof(of_ids[0].compatible));
+	strlcpy(of_ids[1].compatible, bus1, sizeof(of_ids[1].compatible));
+
+	if (of_platform_populate(NULL, of_ids, NULL, NULL))
+		panic("failed to populate DT");
+
+	return 0;
+}
+
 #endif

arch/mips/lantiq/prom.c

@@ -97,16 +97,7 @@ void __init prom_init(void)
 
 int __init plat_of_setup(void)
 {
-	static struct of_device_id of_ids[3];
-
-	if (!of_have_populated_dt())
-		panic("device tree not present");
-
-	strlcpy(of_ids[0].compatible, soc_info.compatible,
-		sizeof(of_ids[0].compatible));
-	strncpy(of_ids[1].compatible, "simple-bus",
-		sizeof(of_ids[1].compatible));
-	return of_platform_populate(NULL, of_ids, NULL, NULL);
+	return __dt_register_buses(soc_info.compatible, "simple-bus");
 }
 
 arch_initcall(plat_of_setup);

arch/mips/ralink/of.c

@@ -74,19 +74,9 @@ void __init plat_mem_setup(void)
 
 static int __init plat_of_setup(void)
 {
-	static struct of_device_id of_ids[3];
-	int len = sizeof(of_ids[0].compatible);
+	__dt_register_buses(soc_info.compatible, "palmbus");
 
-	if (!of_have_populated_dt())
-		panic("device tree not present");
-
-	strlcpy(of_ids[0].compatible, soc_info.compatible, len);
-	strlcpy(of_ids[1].compatible, "palmbus", len);
-
-	if (of_platform_populate(NULL, of_ids, NULL, NULL))
-		panic("failed to populate DT");
-
-	/* make sure ithat the reset controller is setup early */
+	/* make sure that the reset controller is setup early */
 	ralink_rst_init();
 
 	return 0;