1 files changed, 72 insertions, 0 deletions
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 0da795b9dbbf..49e8d302af55 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -24,6 +24,7 @@
 #include "cpuidle.h"
 
 DEFINE_PER_CPU(struct cpuidle_device *, cpuidle_devices);
+DEFINE_PER_CPU(struct cpuidle_device, cpuidle_dev);
 
 DEFINE_MUTEX(cpuidle_lock);
 LIST_HEAD(cpuidle_detected_devices);
@@ -453,6 +454,77 @@ void cpuidle_unregister_device(struct cpuidle_device *dev)
 
 EXPORT_SYMBOL_GPL(cpuidle_unregister_device);
 
+/*
+ * cpuidle_unregister: unregister a driver and the devices. This function
+ * can be used only if the driver has been previously registered through
+ * the cpuidle_register function.
+ *
+ * @drv: a valid pointer to a struct cpuidle_driver
+ */
+void cpuidle_unregister(struct cpuidle_driver *drv)
+{
+	int cpu;
+	struct cpuidle_device *device;
+
+	for_each_possible_cpu(cpu) {
+		device = &per_cpu(cpuidle_dev, cpu);
+		cpuidle_unregister_device(device);
+	}
+
+	cpuidle_unregister_driver(drv);
+}
+EXPORT_SYMBOL_GPL(cpuidle_unregister);
+
+/**
+ * cpuidle_register: registers the driver and the cpu devices with the
+ * coupled_cpus passed as parameter. This function is used for all common
+ * initialization pattern there are in the arch specific drivers. The
+ * devices is globally defined in this file.
+ *
+ * @drv         : a valid pointer to a struct cpuidle_driver
+ * @coupled_cpus: a cpumask for the coupled states
+ *
+ * Returns 0 on success, < 0 otherwise
+ */
+int cpuidle_register(struct cpuidle_driver *drv,
+		     const struct cpumask *const coupled_cpus)
+{
+	int ret, cpu;
+	struct cpuidle_device *device;
+
+	ret = cpuidle_register_driver(drv);
+	if (ret) {
+		pr_err("failed to register cpuidle driver\n");
+		return ret;
+	}
+
+	for_each_possible_cpu(cpu) {
+		device = &per_cpu(cpuidle_dev, cpu);
+		device->cpu = cpu;
+
+#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
+		/*
+		 * On multiplatform for ARM, the coupled idle states could
+		 * enabled in the kernel even if the cpuidle driver does not
+		 * use it. Note, coupled_cpus is a struct copy.
+		 */
+		if (coupled_cpus)
+			device->coupled_cpus = *coupled_cpus;
+#endif
+		ret = cpuidle_register_device(device);
+		if (!ret)
+			continue;
+
+		pr_err("Failed to register cpuidle device for cpu%d\n", cpu);
+
+		cpuidle_unregister(drv);
+		break;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(cpuidle_register);
+
 #ifdef CONFIG_SMP
 
 static void smp_callback(void *v)