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/*
* Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/device.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/reboot.h>
#include "reboot-mode.h"
#define PREFIX "mode-"
struct mode_info {
const char *mode;
u32 magic;
struct list_head list;
};
static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot,
const char *cmd)
{
const char *normal = "normal";
int magic = 0;
struct mode_info *info;
if (!cmd)
cmd = normal;
list_for_each_entry(info, &reboot->head, list) {
if (!strcmp(info->mode, cmd)) {
magic = info->magic;
break;
}
}
return magic;
}
static int reboot_mode_notify(struct notifier_block *this,
unsigned long mode, void *cmd)
{
struct reboot_mode_driver *reboot;
unsigned int magic;
reboot = container_of(this, struct reboot_mode_driver, reboot_notifier);
magic = get_reboot_mode_magic(reboot, cmd);
if (magic)
reboot->write(reboot, magic);
return NOTIFY_DONE;
}
/**
* reboot_mode_register - register a reboot mode driver
* @reboot: reboot mode driver
*
* Returns: 0 on success or a negative error code on failure.
*/
int reboot_mode_register(struct reboot_mode_driver *reboot)
{
struct mode_info *info;
struct property *prop;
struct device_node *np = reboot->dev->of_node;
size_t len = strlen(PREFIX);
int ret;
INIT_LIST_HEAD(&reboot->head);
for_each_property_of_node(np, prop) {
if (strncmp(prop->name, PREFIX, len))
continue;
info = devm_kzalloc(reboot->dev, sizeof(*info), GFP_KERNEL);
if (!info) {
ret = -ENOMEM;
goto error;
}
if (of_property_read_u32(np, prop->name, &info->magic)) {
dev_err(reboot->dev, "reboot mode %s without magic number\n",
info->mode);
devm_kfree(reboot->dev, info);
continue;
}
info->mode = kstrdup_const(prop->name + len, GFP_KERNEL);
if (!info->mode) {
ret = -ENOMEM;
goto error;
} else if (info->mode[0] == '\0') {
kfree_const(info->mode);
ret = -EINVAL;
dev_err(reboot->dev, "invalid mode name(%s): too short!\n",
prop->name);
goto error;
}
list_add_tail(&info->list, &reboot->head);
}
reboot->reboot_notifier.notifier_call = reboot_mode_notify;
register_reboot_notifier(&reboot->reboot_notifier);
return 0;
error:
list_for_each_entry(info, &reboot->head, list)
kfree_const(info->mode);
return ret;
}
EXPORT_SYMBOL_GPL(reboot_mode_register);
/**
* reboot_mode_unregister - unregister a reboot mode driver
* @reboot: reboot mode driver
*/
int reboot_mode_unregister(struct reboot_mode_driver *reboot)
{
struct mode_info *info;
unregister_reboot_notifier(&reboot->reboot_notifier);
list_for_each_entry(info, &reboot->head, list)
kfree_const(info->mode);
return 0;
}
EXPORT_SYMBOL_GPL(reboot_mode_unregister);
static void devm_reboot_mode_release(struct device *dev, void *res)
{
reboot_mode_unregister(*(struct reboot_mode_driver **)res);
}
/**
* devm_reboot_mode_register() - resource managed reboot_mode_register()
* @dev: device to associate this resource with
* @reboot: reboot mode driver
*
* Returns: 0 on success or a negative error code on failure.
*/
int devm_reboot_mode_register(struct device *dev,
struct reboot_mode_driver *reboot)
{
struct reboot_mode_driver **dr;
int rc;
dr = devres_alloc(devm_reboot_mode_release, sizeof(*dr), GFP_KERNEL);
if (!dr)
return -ENOMEM;
rc = reboot_mode_register(reboot);
if (rc) {
devres_free(dr);
return rc;
}
*dr = reboot;
devres_add(dev, dr);
return 0;
}
EXPORT_SYMBOL_GPL(devm_reboot_mode_register);
static int devm_reboot_mode_match(struct device *dev, void *res, void *data)
{
struct reboot_mode_driver **p = res;
if (WARN_ON(!p || !*p))
return 0;
return *p == data;
}
/**
* devm_reboot_mode_unregister() - resource managed reboot_mode_unregister()
* @dev: device to associate this resource with
* @reboot: reboot mode driver
*/
void devm_reboot_mode_unregister(struct device *dev,
struct reboot_mode_driver *reboot)
{
WARN_ON(devres_release(dev,
devm_reboot_mode_release,
devm_reboot_mode_match, reboot));
}
EXPORT_SYMBOL_GPL(devm_reboot_mode_unregister);
MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com");
MODULE_DESCRIPTION("System reboot mode core library");
MODULE_LICENSE("GPL v2");
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