#include <linux/idr.h>
#include <linux/hwmon.h>
#include <linux/gfp.h>
+#include <linux/spinlock.h>
#define HWMON_ID_PREFIX "hwmon"
#define HWMON_ID_FORMAT HWMON_ID_PREFIX "%d"
static struct class *hwmon_class;
static DEFINE_IDR(hwmon_idr);
+static DEFINE_SPINLOCK(idr_lock);
/**
- * hwmon_device_register - register w/ hwmon sysfs class
+ * hwmon_device_register - register w/ hwmon
* @dev: the device to register
*
- * hwmon_device_unregister() must be called when the class device is no
+ * hwmon_device_unregister() must be called when the device is no
* longer needed.
*
- * Returns the pointer to the new struct class device.
+ * Returns the pointer to the new device.
*/
-struct class_device *hwmon_device_register(struct device *dev)
+struct device *hwmon_device_register(struct device *dev)
{
- struct class_device *cdev;
- int id;
+ struct device *hwdev;
+ int id, err;
- if (idr_pre_get(&hwmon_idr, GFP_KERNEL) == 0)
+again:
+ if (unlikely(idr_pre_get(&hwmon_idr, GFP_KERNEL) == 0))
return ERR_PTR(-ENOMEM);
- if (idr_get_new(&hwmon_idr, NULL, &id) < 0)
- return ERR_PTR(-ENOMEM);
+ spin_lock(&idr_lock);
+ err = idr_get_new(&hwmon_idr, NULL, &id);
+ spin_unlock(&idr_lock);
+
+ if (unlikely(err == -EAGAIN))
+ goto again;
+ else if (unlikely(err))
+ return ERR_PTR(err);
id = id & MAX_ID_MASK;
- cdev = class_device_create(hwmon_class, NULL, MKDEV(0,0), dev,
- HWMON_ID_FORMAT, id);
+ hwdev = device_create(hwmon_class, dev, MKDEV(0,0), HWMON_ID_FORMAT, id);
- if (IS_ERR(cdev))
+ if (IS_ERR(hwdev)) {
+ spin_lock(&idr_lock);
idr_remove(&hwmon_idr, id);
+ spin_unlock(&idr_lock);
+ }
- return cdev;
+ return hwdev;
}
/**
* hwmon_device_unregister - removes the previously registered class device
*
- * @cdev: the class device to destroy
+ * @dev: the class device to destroy
*/
-void hwmon_device_unregister(struct class_device *cdev)
+void hwmon_device_unregister(struct device *dev)
{
int id;
- if (sscanf(cdev->class_id, HWMON_ID_FORMAT, &id) == 1) {
- class_device_unregister(cdev);
+ if (likely(sscanf(dev->bus_id, HWMON_ID_FORMAT, &id) == 1)) {
+ device_unregister(dev);
+ spin_lock(&idr_lock);
idr_remove(&hwmon_idr, id);
+ spin_unlock(&idr_lock);
} else
- dev_dbg(cdev->dev,
+ dev_dbg(dev->parent,
"hwmon_device_unregister() failed: bad class ID!\n");
}
class_destroy(hwmon_class);
}
-module_init(hwmon_init);
+subsys_initcall(hwmon_init);
module_exit(hwmon_exit);
EXPORT_SYMBOL_GPL(hwmon_device_register);