1 files changed, 104 insertions, 0 deletions

diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
new file mode 100644
index 000000000000..6ef3069b5710
--- /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);
+}