1 files changed, 397 insertions, 0 deletions

diff --git a/drivers/base/sys.c b/drivers/base/sys.c
new file mode 100644
index 000000000000..cff5a6a2c784
--- /dev/null
+++ b/drivers/base/sys.c
@@ -0,0 +1,397 @@
+/*
+ * sys.c - pseudo-bus for system 'devices' (cpus, PICs, timers, etc)
+ *
+ * Copyright (c) 2002-3 Patrick Mochel
+ *               2002-3 Open Source Development Lab
+ *
+ * This file is released under the GPLv2
+ *
+ * This exports a 'system' bus type.
+ * By default, a 'sys' bus gets added to the root of the system. There will
+ * always be core system devices. Devices can use sysdev_register() to
+ * add themselves as children of the system bus.
+ */
+
+#include <linux/config.h>
+#include <linux/sysdev.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+
+extern struct subsystem devices_subsys;
+
+#define to_sysdev(k) container_of(k, struct sys_device, kobj)
+#define to_sysdev_attr(a) container_of(a, struct sysdev_attribute, attr)
+
+
+static ssize_t
+sysdev_show(struct kobject * kobj, struct attribute * attr, char * buffer)
+{
+        struct sys_device * sysdev = to_sysdev(kobj);
+        struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr);
+
+        if (sysdev_attr->show)
+                return sysdev_attr->show(sysdev, buffer);
+        return 0;
+}
+
+
+static ssize_t
+sysdev_store(struct kobject * kobj, struct attribute * attr,
+             const char * buffer, size_t count)
+{
+        struct sys_device * sysdev = to_sysdev(kobj);
+        struct sysdev_attribute * sysdev_attr = to_sysdev_attr(attr);
+
+        if (sysdev_attr->store)
+                return sysdev_attr->store(sysdev, buffer, count);
+        return 0;
+}
+
+static struct sysfs_ops sysfs_ops = {
+        .show   = sysdev_show,
+        .store  = sysdev_store,
+};
+
+static struct kobj_type ktype_sysdev = {
+        .sysfs_ops      = &sysfs_ops,
+};
+
+
+int sysdev_create_file(struct sys_device * s, struct sysdev_attribute * a)
+{
+        return sysfs_create_file(&s->kobj, &a->attr);
+}
+
+
+void sysdev_remove_file(struct sys_device * s, struct sysdev_attribute * a)
+{
+        sysfs_remove_file(&s->kobj, &a->attr);
+}
+
+EXPORT_SYMBOL_GPL(sysdev_create_file);
+EXPORT_SYMBOL_GPL(sysdev_remove_file);
+
+/*
+ * declare system_subsys
+ */
+static decl_subsys(system, &ktype_sysdev, NULL);
+
+int sysdev_class_register(struct sysdev_class * cls)
+{
+        pr_debug("Registering sysdev class '%s'\n",
+                 kobject_name(&cls->kset.kobj));
+        INIT_LIST_HEAD(&cls->drivers);
+        cls->kset.subsys = &system_subsys;
+        kset_set_kset_s(cls, system_subsys);
+        return kset_register(&cls->kset);
+}
+
+void sysdev_class_unregister(struct sysdev_class * cls)
+{
+        pr_debug("Unregistering sysdev class '%s'\n",
+                 kobject_name(&cls->kset.kobj));
+        kset_unregister(&cls->kset);
+}
+
+EXPORT_SYMBOL_GPL(sysdev_class_register);
+EXPORT_SYMBOL_GPL(sysdev_class_unregister);
+
+
+static LIST_HEAD(sysdev_drivers);
+static DECLARE_MUTEX(sysdev_drivers_lock);
+
+/**
+ *      sysdev_driver_register - Register auxillary driver
+ *      @cls:   Device class driver belongs to.
+ *      @drv:   Driver.
+ *
+ *      If @cls is valid, then @drv is inserted into @cls->drivers to be
+ *      called on each operation on devices of that class. The refcount
+ *      of @cls is incremented.
+ *      Otherwise, @drv is inserted into sysdev_drivers, and called for
+ *      each device.
+ */
+
+int sysdev_driver_register(struct sysdev_class * cls,
+                           struct sysdev_driver * drv)
+{
+        down(&sysdev_drivers_lock);
+        if (cls && kset_get(&cls->kset)) {
+                list_add_tail(&drv->entry, &cls->drivers);
+
+                /* If devices of this class already exist, tell the driver */
+                if (drv->add) {
+                        struct sys_device *dev;
+                        list_for_each_entry(dev, &cls->kset.list, kobj.entry)
+                                drv->add(dev);
+                }
+        } else
+                list_add_tail(&drv->entry, &sysdev_drivers);
+        up(&sysdev_drivers_lock);
+        return 0;
+}
+
+
+/**
+ *      sysdev_driver_unregister - Remove an auxillary driver.
+ *      @cls:   Class driver belongs to.
+ *      @drv:   Driver.
+ */
+void sysdev_driver_unregister(struct sysdev_class * cls,
+                              struct sysdev_driver * drv)
+{
+        down(&sysdev_drivers_lock);
+        list_del_init(&drv->entry);
+        if (cls) {
+                if (drv->remove) {
+                        struct sys_device *dev;
+                        list_for_each_entry(dev, &cls->kset.list, kobj.entry)
+                                drv->remove(dev);
+                }
+                kset_put(&cls->kset);
+        }
+        up(&sysdev_drivers_lock);
+}
+
+EXPORT_SYMBOL_GPL(sysdev_driver_register);
+EXPORT_SYMBOL_GPL(sysdev_driver_unregister);
+
+
+
+/**
+ *      sysdev_register - add a system device to the tree
+ *      @sysdev:        device in question
+ *
+ */
+int sysdev_register(struct sys_device * sysdev)
+{
+        int error;
+        struct sysdev_class * cls = sysdev->cls;
+
+        if (!cls)
+                return -EINVAL;
+
+        /* Make sure the kset is set */
+        sysdev->kobj.kset = &cls->kset;
+
+        /* But make sure we point to the right type for sysfs translation */
+        sysdev->kobj.ktype = &ktype_sysdev;
+        error = kobject_set_name(&sysdev->kobj, "%s%d",
+                         kobject_name(&cls->kset.kobj), sysdev->id);
+        if (error)
+                return error;
+
+        pr_debug("Registering sys device '%s'\n", kobject_name(&sysdev->kobj));
+
+        /* Register the object */
+        error = kobject_register(&sysdev->kobj);
+
+        if (!error) {
+                struct sysdev_driver * drv;
+
+                down(&sysdev_drivers_lock);
+                /* Generic notification is implicit, because it's that
+                 * code that should have called us.
+                 */
+
+                /* Notify global drivers */
+                list_for_each_entry(drv, &sysdev_drivers, entry) {
+                        if (drv->add)
+                                drv->add(sysdev);
+                }
+
+                /* Notify class auxillary drivers */
+                list_for_each_entry(drv, &cls->drivers, entry) {
+                        if (drv->add)
+                                drv->add(sysdev);
+                }
+                up(&sysdev_drivers_lock);
+        }
+        return error;
+}
+
+void sysdev_unregister(struct sys_device * sysdev)
+{
+        struct sysdev_driver * drv;
+
+        down(&sysdev_drivers_lock);
+        list_for_each_entry(drv, &sysdev_drivers, entry) {
+                if (drv->remove)
+                        drv->remove(sysdev);
+        }
+
+        list_for_each_entry(drv, &sysdev->cls->drivers, entry) {
+                if (drv->remove)
+                        drv->remove(sysdev);
+        }
+        up(&sysdev_drivers_lock);
+
+        kobject_unregister(&sysdev->kobj);
+}
+
+
+
+/**
+ *      sysdev_shutdown - Shut down all system devices.
+ *
+ *      Loop over each class of system devices, and the devices in each
+ *      of those classes. For each device, we call the shutdown method for
+ *      each driver registered for the device - the globals, the auxillaries,
+ *      and the class driver.
+ *
+ *      Note: The list is iterated in reverse order, so that we shut down
+ *      child devices before we shut down thier parents. The list ordering
+ *      is guaranteed by virtue of the fact that child devices are registered
+ *      after their parents.
+ */
+
+void sysdev_shutdown(void)
+{
+        struct sysdev_class * cls;
+
+        pr_debug("Shutting Down System Devices\n");
+
+        down(&sysdev_drivers_lock);
+        list_for_each_entry_reverse(cls, &system_subsys.kset.list,
+                                    kset.kobj.entry) {
+                struct sys_device * sysdev;
+
+                pr_debug("Shutting down type '%s':\n",
+                         kobject_name(&cls->kset.kobj));
+
+                list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
+                        struct sysdev_driver * drv;
+                        pr_debug(" %s\n", kobject_name(&sysdev->kobj));
+
+                        /* Call global drivers first. */
+                        list_for_each_entry(drv, &sysdev_drivers, entry) {
+                                if (drv->shutdown)
+                                        drv->shutdown(sysdev);
+                        }
+
+                        /* Call auxillary drivers next. */
+                        list_for_each_entry(drv, &cls->drivers, entry) {
+                                if (drv->shutdown)
+                                        drv->shutdown(sysdev);
+                        }
+
+                        /* Now call the generic one */
+                        if (cls->shutdown)
+                                cls->shutdown(sysdev);
+                }
+        }
+        up(&sysdev_drivers_lock);
+}
+
+
+/**
+ *      sysdev_suspend - Suspend all system devices.
+ *      @state:         Power state to enter.
+ *
+ *      We perform an almost identical operation as sys_device_shutdown()
+ *      above, though calling ->suspend() instead. Interrupts are disabled
+ *      when this called. Devices are responsible for both saving state and
+ *      quiescing or powering down the device.
+ *
+ *      This is only called by the device PM core, so we let them handle
+ *      all synchronization.
+ */
+
+int sysdev_suspend(u32 state)
+{
+        struct sysdev_class * cls;
+
+        pr_debug("Suspending System Devices\n");
+
+        list_for_each_entry_reverse(cls, &system_subsys.kset.list,
+                                    kset.kobj.entry) {
+                struct sys_device * sysdev;
+
+                pr_debug("Suspending type '%s':\n",
+                         kobject_name(&cls->kset.kobj));
+
+                list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
+                        struct sysdev_driver * drv;
+                        pr_debug(" %s\n", kobject_name(&sysdev->kobj));
+
+                        /* Call global drivers first. */
+                        list_for_each_entry(drv, &sysdev_drivers, entry) {
+                                if (drv->suspend)
+                                        drv->suspend(sysdev, state);
+                        }
+
+                        /* Call auxillary drivers next. */
+                        list_for_each_entry(drv, &cls->drivers, entry) {
+                                if (drv->suspend)
+                                        drv->suspend(sysdev, state);
+                        }
+
+                        /* Now call the generic one */
+                        if (cls->suspend)
+                                cls->suspend(sysdev, state);
+                }
+        }
+        return 0;
+}
+
+
+/**
+ *      sysdev_resume - Bring system devices back to life.
+ *
+ *      Similar to sys_device_suspend(), but we iterate the list forwards
+ *      to guarantee that parent devices are resumed before their children.
+ *
+ *      Note: Interrupts are disabled when called.
+ */
+
+int sysdev_resume(void)
+{
+        struct sysdev_class * cls;
+
+        pr_debug("Resuming System Devices\n");
+
+        list_for_each_entry(cls, &system_subsys.kset.list, kset.kobj.entry) {
+                struct sys_device * sysdev;
+
+                pr_debug("Resuming type '%s':\n",
+                         kobject_name(&cls->kset.kobj));
+
+                list_for_each_entry(sysdev, &cls->kset.list, kobj.entry) {
+                        struct sysdev_driver * drv;
+                        pr_debug(" %s\n", kobject_name(&sysdev->kobj));
+
+                        /* First, call the class-specific one */
+                        if (cls->resume)
+                                cls->resume(sysdev);
+
+                        /* Call auxillary drivers next. */
+                        list_for_each_entry(drv, &cls->drivers, entry) {
+                                if (drv->resume)
+                                        drv->resume(sysdev);
+                        }
+
+                        /* Call global drivers. */
+                        list_for_each_entry(drv, &sysdev_drivers, entry) {
+                                if (drv->resume)
+                                        drv->resume(sysdev);
+                        }
+
+                }
+        }
+        return 0;
+}
+
+
+int __init system_bus_init(void)
+{
+        system_subsys.kset.kobj.parent = &devices_subsys.kset.kobj;
+        return subsystem_register(&system_subsys);
+}
+
+EXPORT_SYMBOL_GPL(sysdev_register);
+EXPORT_SYMBOL_GPL(sysdev_unregister);