ARM: shmobile: add cpufreq-cpu0 driver for common SH-Mobile

I add a new file(cpufreq.c) for the following reasons.
- Registration of platform_device must be unified in SH-Mobile.
- We can't create a node of cpufreq drivers into device tree.
  (Because cpufreq driver is virtual device.)

Signed-off-by: Gaku Inami <gaku.inami.xw@bp.renesas.com>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

arch/arm/mach-shmobile/Makefile

@@ -48,6 +48,7 @@ obj-$(CONFIG_ARCH_SH7372)	+= entry-intc.o
 # PM objects
 obj-$(CONFIG_SUSPEND)		+= suspend.o
 obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o
+obj-$(CONFIG_CPU_FREQ)		+= cpufreq.o
 obj-$(CONFIG_ARCH_SH7372)	+= pm-sh7372.o sleep-sh7372.o pm-rmobile.o
 obj-$(CONFIG_ARCH_SH73A0)	+= pm-sh73a0.o
 obj-$(CONFIG_ARCH_R8A7740)	+= pm-r8a7740.o pm-rmobile.o

arch/arm/mach-shmobile/cpufreq.c

@@ -0,0 +1,31 @@
+/*
+ * CPUFreq support code for SH-Mobile ARM
+ *
+ *  Copyright (C) 2014 Gaku Inami
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+int __init shmobile_cpufreq_init(void)
+{
+	struct device_node *np;
+
+	np = of_cpu_device_node_get(0);
+	if (np == NULL) {
+		pr_err("failed to find cpu0 node\n");
+		return 0;
+	}
+
+	if (of_get_property(np, "operating-points", NULL))
+		platform_device_register_simple("cpufreq-cpu0", -1, NULL, 0);
+
+	of_node_put(np);
+
+	return 0;
+}

arch/arm/mach-shmobile/include/mach/common.h

@@ -45,12 +45,19 @@ int shmobile_cpuidle_init(void);
 static inline int shmobile_cpuidle_init(void) { return 0; }
 #endif
 
+#ifdef CONFIG_CPU_FREQ
+int shmobile_cpufreq_init(void);
+#else
+static inline int shmobile_cpufreq_init(void) { return 0; }
+#endif
+
 extern void __iomem *shmobile_scu_base;
 
 static inline void __init shmobile_init_late(void)
 {
 	shmobile_suspend_init();
 	shmobile_cpuidle_init();
+	shmobile_cpufreq_init();
 }
 
 #endif /* __ARCH_MACH_COMMON_H */