1 files changed, 104 insertions, 0 deletions
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
new file mode 100644
index 0000000..6ef3069
--- /dev/null
+++ b/drivers/base/cpu.c
@@ -0,0 +1,104 @@
+/*
+ * drivers/base/cpu.c - basic CPU class support
+ */
+
+#include <linux/sysdev.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/cpu.h>
+#include <linux/topology.h>
+#include <linux/device.h>
+
+
+struct sysdev_class cpu_sysdev_class = {
+	set_kset_name("cpu"),
+};
+EXPORT_SYMBOL(cpu_sysdev_class);
+
+#ifdef CONFIG_HOTPLUG_CPU
+static ssize_t show_online(struct sys_device *dev, char *buf)
+{
+	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
+
+	return sprintf(buf, "%u\n", !!cpu_online(cpu->sysdev.id));
+}
+
+static ssize_t store_online(struct sys_device *dev, const char *buf,
+			    size_t count)
+{
+	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
+	ssize_t ret;
+
+	switch (buf[0]) {
+	case '0':
+		ret = cpu_down(cpu->sysdev.id);
+		if (!ret)
+			kobject_hotplug(&dev->kobj, KOBJ_OFFLINE);
+		break;
+	case '1':
+		ret = cpu_up(cpu->sysdev.id);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	if (ret >= 0)
+		ret = count;
+	return ret;
+}
+static SYSDEV_ATTR(online, 0600, show_online, store_online);
+
+static void __devinit register_cpu_control(struct cpu *cpu)
+{
+	sysdev_create_file(&cpu->sysdev, &attr_online);
+}
+void unregister_cpu(struct cpu *cpu, struct node *root)
+{
+
+	if (root)
+		sysfs_remove_link(&root->sysdev.kobj,
+				  kobject_name(&cpu->sysdev.kobj));
+	sysdev_remove_file(&cpu->sysdev, &attr_online);
+
+	sysdev_unregister(&cpu->sysdev);
+
+	return;
+}
+#else /* ... !CONFIG_HOTPLUG_CPU */
+static inline void register_cpu_control(struct cpu *cpu)
+{
+}
+#endif /* CONFIG_HOTPLUG_CPU */
+
+/*
+ * register_cpu - Setup a driverfs device for a CPU.
+ * @cpu - Callers can set the cpu->no_control field to 1, to indicate not to
+ *		  generate a control file in sysfs for this CPU.
+ * @num - CPU number to use when creating the device.
+ *
+ * Initialize and register the CPU device.
+ */
+int __devinit register_cpu(struct cpu *cpu, int num, struct node *root)
+{
+	int error;
+
+	cpu->node_id = cpu_to_node(num);
+	cpu->sysdev.id = num;
+	cpu->sysdev.cls = &cpu_sysdev_class;
+
+	error = sysdev_register(&cpu->sysdev);
+	if (!error && root)
+		error = sysfs_create_link(&root->sysdev.kobj,
+					  &cpu->sysdev.kobj,
+					  kobject_name(&cpu->sysdev.kobj));
+	if (!error && !cpu->no_control)
+		register_cpu_control(cpu);
+	return error;
+}
+
+
+
+int __init cpu_dev_init(void)
+{
+	return sysdev_class_register(&cpu_sysdev_class);
+}