linux/drivers/power/reset/zx-reboot.c

90 lines
2.0 KiB
C

/*
* ZTE zx296702 SoC reset code
*
* Copyright (c) 2015 Linaro Ltd.
*
* Author: Jun Nie <jun.nie@linaro.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/notifier.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
static void __iomem *base;
static void __iomem *pcu_base;
static int zx_restart_handler(struct notifier_block *this,
unsigned long mode, void *cmd)
{
writel_relaxed(1, base + 0xb0);
writel_relaxed(1, pcu_base + 0x34);
mdelay(50);
pr_emerg("Unable to restart system\n");
return NOTIFY_DONE;
}
static struct notifier_block zx_restart_nb = {
.notifier_call = zx_restart_handler,
.priority = 128,
};
static int zx_reboot_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
int err;
base = of_iomap(np, 0);
if (!base) {
WARN(1, "failed to map base address");
return -ENODEV;
}
np = of_find_compatible_node(NULL, NULL, "zte,zx296702-pcu");
pcu_base = of_iomap(np, 0);
of_node_put(np);
if (!pcu_base) {
iounmap(base);
WARN(1, "failed to map pcu_base address");
return -ENODEV;
}
err = register_restart_handler(&zx_restart_nb);
if (err) {
iounmap(base);
iounmap(pcu_base);
dev_err(&pdev->dev, "Register restart handler failed(err=%d)\n",
err);
}
return err;
}
static const struct of_device_id zx_reboot_of_match[] = {
{ .compatible = "zte,sysctrl" },
{}
};
MODULE_DEVICE_TABLE(of, zx_reboot_of_match);
static struct platform_driver zx_reboot_driver = {
.probe = zx_reboot_probe,
.driver = {
.name = "zx-reboot",
.of_match_table = zx_reboot_of_match,
},
};
module_platform_driver(zx_reboot_driver);
MODULE_DESCRIPTION("ZTE SoCs reset driver");
MODULE_AUTHOR("Jun Nie <jun.nie@linaro.org>");
MODULE_LICENSE("GPL v2");