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// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2021 Emil Renner Berthing
*/
#include <linux/mfd/tps65086.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
struct tps65086_restart {
struct notifier_block handler;
struct device *dev;
};
static int tps65086_restart_notify(struct notifier_block *this,
unsigned long mode, void *cmd)
{
struct tps65086_restart *tps65086_restart =
container_of(this, struct tps65086_restart, handler);
struct tps65086 *tps65086 = dev_get_drvdata(tps65086_restart->dev->parent);
int ret;
ret = regmap_write(tps65086->regmap, TPS65086_FORCESHUTDN, 1);
if (ret) {
dev_err(tps65086_restart->dev, "%s: error writing to tps65086 pmic: %d\n",
__func__, ret);
return NOTIFY_DONE;
}
/* give it a little time */
mdelay(200);
WARN_ON(1);
return NOTIFY_DONE;
}
static int tps65086_restart_probe(struct platform_device *pdev)
{
struct tps65086_restart *tps65086_restart;
int ret;
tps65086_restart = devm_kzalloc(&pdev->dev, sizeof(*tps65086_restart), GFP_KERNEL);
if (!tps65086_restart)
return -ENOMEM;
platform_set_drvdata(pdev, tps65086_restart);
tps65086_restart->handler.notifier_call = tps65086_restart_notify;
tps65086_restart->handler.priority = 192;
tps65086_restart->dev = &pdev->dev;
ret = register_restart_handler(&tps65086_restart->handler);
if (ret) {
dev_err(&pdev->dev, "%s: cannot register restart handler: %d\n",
__func__, ret);
return -ENODEV;
}
return 0;
}
static void tps65086_restart_remove(struct platform_device *pdev)
{
struct tps65086_restart *tps65086_restart = platform_get_drvdata(pdev);
int ret;
ret = unregister_restart_handler(&tps65086_restart->handler);
if (ret) {
/*
* tps65086_restart_probe() registered the restart handler. So
* unregistering should work fine. Checking the error code
* shouldn't be needed, still doing it for completeness.
*/
dev_err(&pdev->dev, "%s: cannot unregister restart handler: %d\n",
__func__, ret);
}
}
static const struct platform_device_id tps65086_restart_id_table[] = {
{ "tps65086-reset", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, tps65086_restart_id_table);
static struct platform_driver tps65086_restart_driver = {
.driver = {
.name = "tps65086-restart",
},
.probe = tps65086_restart_probe,
.remove_new = tps65086_restart_remove,
.id_table = tps65086_restart_id_table,
};
module_platform_driver(tps65086_restart_driver);
MODULE_AUTHOR("Emil Renner Berthing <kernel@esmil.dk>");
MODULE_DESCRIPTION("TPS65086 restart driver");
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