// SPDX-License-Identifier: GPL-2.0-only
|
/*
|
* Copyright (C) 2014 STMicroelectronics
|
*
|
* Power off Restart driver, used in STMicroelectronics devices.
|
*
|
* Author: Christophe Kerello <christophe.kerello@st.com>
|
*/
|
|
#include <linux/module.h>
|
#include <linux/of.h>
|
#include <linux/of_platform.h>
|
#include <linux/platform_device.h>
|
#include <linux/mfd/syscon.h>
|
#include <linux/reboot.h>
|
#include <linux/regmap.h>
|
|
struct reset_syscfg {
|
struct regmap *regmap;
|
/* syscfg used for reset */
|
unsigned int offset_rst;
|
unsigned int mask_rst;
|
/* syscfg used for unmask the reset */
|
unsigned int offset_rst_msk;
|
unsigned int mask_rst_msk;
|
};
|
|
/* STiH407 */
|
#define STIH407_SYSCFG_4000 0x0
|
#define STIH407_SYSCFG_4008 0x20
|
|
static struct reset_syscfg stih407_reset = {
|
.offset_rst = STIH407_SYSCFG_4000,
|
.mask_rst = BIT(0),
|
.offset_rst_msk = STIH407_SYSCFG_4008,
|
.mask_rst_msk = BIT(0)
|
};
|
|
|
static struct reset_syscfg *st_restart_syscfg;
|
|
static int st_restart(struct notifier_block *this, unsigned long mode,
|
void *cmd)
|
{
|
/* reset syscfg updated */
|
regmap_update_bits(st_restart_syscfg->regmap,
|
st_restart_syscfg->offset_rst,
|
st_restart_syscfg->mask_rst,
|
0);
|
|
/* unmask the reset */
|
regmap_update_bits(st_restart_syscfg->regmap,
|
st_restart_syscfg->offset_rst_msk,
|
st_restart_syscfg->mask_rst_msk,
|
0);
|
|
return NOTIFY_DONE;
|
}
|
|
static struct notifier_block st_restart_nb = {
|
.notifier_call = st_restart,
|
.priority = 192,
|
};
|
|
static const struct of_device_id st_reset_of_match[] = {
|
{
|
.compatible = "st,stih407-restart",
|
.data = (void *)&stih407_reset,
|
},
|
{}
|
};
|
|
static int st_reset_probe(struct platform_device *pdev)
|
{
|
struct device_node *np = pdev->dev.of_node;
|
const struct of_device_id *match;
|
struct device *dev = &pdev->dev;
|
|
match = of_match_device(st_reset_of_match, dev);
|
if (!match)
|
return -ENODEV;
|
|
st_restart_syscfg = (struct reset_syscfg *)match->data;
|
|
st_restart_syscfg->regmap =
|
syscon_regmap_lookup_by_phandle(np, "st,syscfg");
|
if (IS_ERR(st_restart_syscfg->regmap)) {
|
dev_err(dev, "No syscfg phandle specified\n");
|
return PTR_ERR(st_restart_syscfg->regmap);
|
}
|
|
return register_restart_handler(&st_restart_nb);
|
}
|
|
static struct platform_driver st_reset_driver = {
|
.probe = st_reset_probe,
|
.driver = {
|
.name = "st_reset",
|
.of_match_table = st_reset_of_match,
|
},
|
};
|
|
static int __init st_reset_init(void)
|
{
|
return platform_driver_register(&st_reset_driver);
|
}
|
|
device_initcall(st_reset_init);
|
|
MODULE_AUTHOR("Christophe Kerello <christophe.kerello@st.com>");
|
MODULE_DESCRIPTION("STMicroelectronics Power off Restart driver");
|
MODULE_LICENSE("GPL v2");
|
