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Diffstat (limited to 'drivers/cpuidle/sysfs.c')
-rw-r--r--drivers/cpuidle/sysfs.c361
1 files changed, 361 insertions, 0 deletions
diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c
new file mode 100644
index 00000000000..0f3515e77d4
--- /dev/null
+++ b/drivers/cpuidle/sysfs.c
@@ -0,0 +1,361 @@
+/*
+ * sysfs.c - sysfs support
+ *
+ * (C) 2006-2007 Shaohua Li <shaohua.li@intel.com>
+ *
+ * This code is licenced under the GPL.
+ */
+
+#include <linux/kernel.h>
+#include <linux/cpuidle.h>
+#include <linux/sysfs.h>
+#include <linux/cpu.h>
+
+#include "cpuidle.h"
+
+static unsigned int sysfs_switch;
+static int __init cpuidle_sysfs_setup(char *unused)
+{
+ sysfs_switch = 1;
+ return 1;
+}
+__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup);
+
+static ssize_t show_available_governors(struct sys_device *dev, char *buf)
+{
+ ssize_t i = 0;
+ struct cpuidle_governor *tmp;
+
+ mutex_lock(&cpuidle_lock);
+ list_for_each_entry(tmp, &cpuidle_governors, governor_list) {
+ if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - CPUIDLE_NAME_LEN - 2))
+ goto out;
+ i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name);
+ }
+
+out:
+ i+= sprintf(&buf[i], "\n");
+ mutex_unlock(&cpuidle_lock);
+ return i;
+}
+
+static ssize_t show_current_driver(struct sys_device *dev, char *buf)
+{
+ ssize_t ret;
+
+ spin_lock(&cpuidle_driver_lock);
+ if (cpuidle_curr_driver)
+ ret = sprintf(buf, "%s\n", cpuidle_curr_driver->name);
+ else
+ ret = sprintf(buf, "none\n");
+ spin_unlock(&cpuidle_driver_lock);
+
+ return ret;
+}
+
+static ssize_t show_current_governor(struct sys_device *dev, char *buf)
+{
+ ssize_t ret;
+
+ mutex_lock(&cpuidle_lock);
+ if (cpuidle_curr_governor)
+ ret = sprintf(buf, "%s\n", cpuidle_curr_governor->name);
+ else
+ ret = sprintf(buf, "none\n");
+ mutex_unlock(&cpuidle_lock);
+
+ return ret;
+}
+
+static ssize_t store_current_governor(struct sys_device *dev,
+ const char *buf, size_t count)
+{
+ char gov_name[CPUIDLE_NAME_LEN];
+ int ret = -EINVAL;
+ size_t len = count;
+ struct cpuidle_governor *gov;
+
+ if (!len || len >= sizeof(gov_name))
+ return -EINVAL;
+
+ memcpy(gov_name, buf, len);
+ gov_name[len] = '\0';
+ if (gov_name[len - 1] == '\n')
+ gov_name[--len] = '\0';
+
+ mutex_lock(&cpuidle_lock);
+
+ list_for_each_entry(gov, &cpuidle_governors, governor_list) {
+ if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) {
+ ret = cpuidle_switch_governor(gov);
+ break;
+ }
+ }
+
+ mutex_unlock(&cpuidle_lock);
+
+ if (ret)
+ return ret;
+ else
+ return count;
+}
+
+static SYSDEV_ATTR(current_driver, 0444, show_current_driver, NULL);
+static SYSDEV_ATTR(current_governor_ro, 0444, show_current_governor, NULL);
+
+static struct attribute *cpuclass_default_attrs[] = {
+ &attr_current_driver.attr,
+ &attr_current_governor_ro.attr,
+ NULL
+};
+
+static SYSDEV_ATTR(available_governors, 0444, show_available_governors, NULL);
+static SYSDEV_ATTR(current_governor, 0644, show_current_governor,
+ store_current_governor);
+
+static struct attribute *cpuclass_switch_attrs[] = {
+ &attr_available_governors.attr,
+ &attr_current_driver.attr,
+ &attr_current_governor.attr,
+ NULL
+};
+
+static struct attribute_group cpuclass_attr_group = {
+ .attrs = cpuclass_default_attrs,
+ .name = "cpuidle",
+};
+
+/**
+ * cpuidle_add_class_sysfs - add CPU global sysfs attributes
+ */
+int cpuidle_add_class_sysfs(struct sysdev_class *cls)
+{
+ if (sysfs_switch)
+ cpuclass_attr_group.attrs = cpuclass_switch_attrs;
+
+ return sysfs_create_group(&cls->kset.kobj, &cpuclass_attr_group);
+}
+
+/**
+ * cpuidle_remove_class_sysfs - remove CPU global sysfs attributes
+ */
+void cpuidle_remove_class_sysfs(struct sysdev_class *cls)
+{
+ sysfs_remove_group(&cls->kset.kobj, &cpuclass_attr_group);
+}
+
+struct cpuidle_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct cpuidle_device *, char *);
+ ssize_t (*store)(struct cpuidle_device *, const char *, size_t count);
+};
+
+#define define_one_ro(_name, show) \
+ static struct cpuidle_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
+#define define_one_rw(_name, show, store) \
+ static struct cpuidle_attr attr_##_name = __ATTR(_name, 0644, show, store)
+
+#define kobj_to_cpuidledev(k) container_of(k, struct cpuidle_device, kobj)
+#define attr_to_cpuidleattr(a) container_of(a, struct cpuidle_attr, attr)
+static ssize_t cpuidle_show(struct kobject * kobj, struct attribute * attr ,char * buf)
+{
+ int ret = -EIO;
+ struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
+ struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
+
+ if (cattr->show) {
+ mutex_lock(&cpuidle_lock);
+ ret = cattr->show(dev, buf);
+ mutex_unlock(&cpuidle_lock);
+ }
+ return ret;
+}
+
+static ssize_t cpuidle_store(struct kobject * kobj, struct attribute * attr,
+ const char * buf, size_t count)
+{
+ int ret = -EIO;
+ struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
+ struct cpuidle_attr * cattr = attr_to_cpuidleattr(attr);
+
+ if (cattr->store) {
+ mutex_lock(&cpuidle_lock);
+ ret = cattr->store(dev, buf, count);
+ mutex_unlock(&cpuidle_lock);
+ }
+ return ret;
+}
+
+static struct sysfs_ops cpuidle_sysfs_ops = {
+ .show = cpuidle_show,
+ .store = cpuidle_store,
+};
+
+static void cpuidle_sysfs_release(struct kobject *kobj)
+{
+ struct cpuidle_device *dev = kobj_to_cpuidledev(kobj);
+
+ complete(&dev->kobj_unregister);
+}
+
+static struct kobj_type ktype_cpuidle = {
+ .sysfs_ops = &cpuidle_sysfs_ops,
+ .release = cpuidle_sysfs_release,
+};
+
+struct cpuidle_state_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct cpuidle_state *, char *);
+ ssize_t (*store)(struct cpuidle_state *, const char *, size_t);
+};
+
+#define define_one_state_ro(_name, show) \
+static struct cpuidle_state_attr attr_##_name = __ATTR(_name, 0444, show, NULL)
+
+#define define_show_state_function(_name) \
+static ssize_t show_state_##_name(struct cpuidle_state *state, char *buf) \
+{ \
+ return sprintf(buf, "%u\n", state->_name);\
+}
+
+static ssize_t show_state_name(struct cpuidle_state *state, char *buf)
+{
+ return sprintf(buf, "%s\n", state->name);
+}
+
+define_show_state_function(exit_latency)
+define_show_state_function(power_usage)
+define_show_state_function(usage)
+define_show_state_function(time)
+define_one_state_ro(name, show_state_name);
+define_one_state_ro(latency, show_state_exit_latency);
+define_one_state_ro(power, show_state_power_usage);
+define_one_state_ro(usage, show_state_usage);
+define_one_state_ro(time, show_state_time);
+
+static struct attribute *cpuidle_state_default_attrs[] = {
+ &attr_name.attr,
+ &attr_latency.attr,
+ &attr_power.attr,
+ &attr_usage.attr,
+ &attr_time.attr,
+ NULL
+};
+
+#define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj)
+#define kobj_to_state(k) (kobj_to_state_obj(k)->state)
+#define attr_to_stateattr(a) container_of(a, struct cpuidle_state_attr, attr)
+static ssize_t cpuidle_state_show(struct kobject * kobj,
+ struct attribute * attr ,char * buf)
+{
+ int ret = -EIO;
+ struct cpuidle_state *state = kobj_to_state(kobj);
+ struct cpuidle_state_attr * cattr = attr_to_stateattr(attr);
+
+ if (cattr->show)
+ ret = cattr->show(state, buf);
+
+ return ret;
+}
+
+static struct sysfs_ops cpuidle_state_sysfs_ops = {
+ .show = cpuidle_state_show,
+};
+
+static void cpuidle_state_sysfs_release(struct kobject *kobj)
+{
+ struct cpuidle_state_kobj *state_obj = kobj_to_state_obj(kobj);
+
+ complete(&state_obj->kobj_unregister);
+}
+
+static struct kobj_type ktype_state_cpuidle = {
+ .sysfs_ops = &cpuidle_state_sysfs_ops,
+ .default_attrs = cpuidle_state_default_attrs,
+ .release = cpuidle_state_sysfs_release,
+};
+
+static void inline cpuidle_free_state_kobj(struct cpuidle_device *device, int i)
+{
+ kobject_unregister(&device->kobjs[i]->kobj);
+ wait_for_completion(&device->kobjs[i]->kobj_unregister);
+ kfree(device->kobjs[i]);
+ device->kobjs[i] = NULL;
+}
+
+/**
+ * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes
+ * @device: the target device
+ */
+int cpuidle_add_state_sysfs(struct cpuidle_device *device)
+{
+ int i, ret = -ENOMEM;
+ struct cpuidle_state_kobj *kobj;
+
+ /* state statistics */
+ for (i = 0; i < device->state_count; i++) {
+ kobj = kzalloc(sizeof(struct cpuidle_state_kobj), GFP_KERNEL);
+ if (!kobj)
+ goto error_state;
+ kobj->state = &device->states[i];
+ init_completion(&kobj->kobj_unregister);
+
+ kobj->kobj.parent = &device->kobj;
+ kobj->kobj.ktype = &ktype_state_cpuidle;
+ kobject_set_name(&kobj->kobj, "state%d", i);
+ ret = kobject_register(&kobj->kobj);
+ if (ret) {
+ kfree(kobj);
+ goto error_state;
+ }
+ device->kobjs[i] = kobj;
+ }
+
+ return 0;
+
+error_state:
+ for (i = i - 1; i >= 0; i--)
+ cpuidle_free_state_kobj(device, i);
+ return ret;
+}
+
+/**
+ * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes
+ * @device: the target device
+ */
+void cpuidle_remove_state_sysfs(struct cpuidle_device *device)
+{
+ int i;
+
+ for (i = 0; i < device->state_count; i++)
+ cpuidle_free_state_kobj(device, i);
+}
+
+/**
+ * cpuidle_add_sysfs - creates a sysfs instance for the target device
+ * @sysdev: the target device
+ */
+int cpuidle_add_sysfs(struct sys_device *sysdev)
+{
+ int cpu = sysdev->id;
+ struct cpuidle_device *dev;
+
+ dev = per_cpu(cpuidle_devices, cpu);
+ dev->kobj.parent = &sysdev->kobj;
+ dev->kobj.ktype = &ktype_cpuidle;
+ kobject_set_name(&dev->kobj, "%s", "cpuidle");
+ return kobject_register(&dev->kobj);
+}
+
+/**
+ * cpuidle_remove_sysfs - deletes a sysfs instance on the target device
+ * @sysdev: the target device
+ */
+void cpuidle_remove_sysfs(struct sys_device *sysdev)
+{
+ int cpu = sysdev->id;
+ struct cpuidle_device *dev;
+
+ dev = per_cpu(cpuidle_devices, cpu);
+ kobject_unregister(&dev->kobj);
+}