Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Generic Syscon Poweroff Driver
 *
 * Copyright (c) 2015, National Instruments Corp.
 * Author: Moritz Fischer <moritz.fischer@ettus.com>
 */
 
#include <linux/kallsyms.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/notifier.h>
#include <linux/mfd/syscon.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/regmap.h>
 
static struct regmap *map;
static u32 offset;
static u32 value;
static u32 mask;
 
static void syscon_poweroff(void)
{
<------>/* Issue the poweroff */
<------>regmap_update_bits(map, offset, mask, value);
 
<------>mdelay(1000);
 
<------>pr_emerg("Unable to poweroff system\n");
}
 
static int syscon_poweroff_probe(struct platform_device *pdev)
{
<------>char symname[KSYM_NAME_LEN];
<------>int mask_err, value_err;
 
<------>map = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
<------>if (IS_ERR(map)) {
<------><------>dev_err(&pdev->dev, "unable to get syscon");
<------><------>return PTR_ERR(map);
<------>}
 
<------>if (of_property_read_u32(pdev->dev.of_node, "offset", &offset)) {
<------><------>dev_err(&pdev->dev, "unable to read 'offset'");
<------><------>return -EINVAL;
<------>}
 
<------>value_err = of_property_read_u32(pdev->dev.of_node, "value", &value);
<------>mask_err = of_property_read_u32(pdev->dev.of_node, "mask", &mask);
<------>if (value_err && mask_err) {
<------><------>dev_err(&pdev->dev, "unable to read 'value' and 'mask'");
<------><------>return -EINVAL;
<------>}
 
<------>if (value_err) {
<------><------>/* support old binding */
<------><------>value = mask;
<------><------>mask = 0xFFFFFFFF;
<------>} else if (mask_err) {
<------><------>/* support value without mask*/
<------><------>mask = 0xFFFFFFFF;
<------>}
 
<------>if (pm_power_off) {
<------><------>lookup_symbol_name((ulong)pm_power_off, symname);
<------><------>dev_err(&pdev->dev,
<------><------>"pm_power_off already claimed %p %s",
<------><------>pm_power_off, symname);
<------><------>return -EBUSY;
<------>}
 
<------>pm_power_off = syscon_poweroff;
 
<------>return 0;
}
 
static int syscon_poweroff_remove(struct platform_device *pdev)
{
<------>if (pm_power_off == syscon_poweroff)
<------><------>pm_power_off = NULL;
 
<------>return 0;
}
 
static const struct of_device_id syscon_poweroff_of_match[] = {
<------>{ .compatible = "syscon-poweroff" },
<------>{}
};
 
static struct platform_driver syscon_poweroff_driver = {
<------>.probe = syscon_poweroff_probe,
<------>.remove = syscon_poweroff_remove,
<------>.driver = {
<------><------>.name = "syscon-poweroff",
<------><------>.of_match_table = syscon_poweroff_of_match,
<------>},
};
 
static int __init syscon_poweroff_register(void)
{
<------>return platform_driver_register(&syscon_poweroff_driver);
}
device_initcall(syscon_poweroff_register);