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// SPDX-License-Identifier: GPL-2.0-or-later
/* Firmware attributes class helper module */
#include <linux/mutex.h>
#include <linux/device/class.h>
#include <linux/module.h>
#include "firmware_attributes_class.h"
static DEFINE_MUTEX(fw_attr_lock);
static int fw_attr_inuse;
static const struct class firmware_attributes_class = {
.name = "firmware-attributes",
};
int fw_attributes_class_get(const struct class **fw_attr_class)
{
int err;
mutex_lock(&fw_attr_lock);
if (!fw_attr_inuse) { /*first time class is being used*/
err = class_register(&firmware_attributes_class);
if (err) {
mutex_unlock(&fw_attr_lock);
return err;
}
}
fw_attr_inuse++;
*fw_attr_class = &firmware_attributes_class;
mutex_unlock(&fw_attr_lock);
return 0;
}
EXPORT_SYMBOL_GPL(fw_attributes_class_get);
int fw_attributes_class_put(void)
{
mutex_lock(&fw_attr_lock);
if (!fw_attr_inuse) {
mutex_unlock(&fw_attr_lock);
return -EINVAL;
}
fw_attr_inuse--;
if (!fw_attr_inuse) /* No more consumers */
class_unregister(&firmware_attributes_class);
mutex_unlock(&fw_attr_lock);
return 0;
}
EXPORT_SYMBOL_GPL(fw_attributes_class_put);
MODULE_AUTHOR("Mark Pearson <markpearson@lenovo.com>");
MODULE_LICENSE("GPL");
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