/*
* Copyright (C) 2014 STMicroelectronics
*
* Power off Restart driver, used in STMicroelectronics devices.
*
* Author: Christophe Kerello <christophe.kerello@st.com>
*
* 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/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;
};
/* STiH415 */
#define STIH415_SYSCFG_11 0x2c
#define STIH415_SYSCFG_15 0x3c
static struct reset_syscfg stih415_reset = {
.offset_rst = STIH415_SYSCFG_11,
.mask_rst = BIT(0),
.offset_rst_msk = STIH415_SYSCFG_15,
.mask_rst_msk = BIT(0)
};
/* STiH416 */
#define STIH416_SYSCFG_500 0x7d0
#define STIH416_SYSCFG_504 0x7e0
static struct reset_syscfg stih416_reset = {
.offset_rst = STIH416_SYSCFG_500,
.mask_rst = BIT(0),
.offset_rst_msk = STIH416_SYSCFG_504,
.mask_rst_msk = BIT(0)
};
/* 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)
};
/* STiD127 */
#define STID127_SYSCFG_700 0x0
#define STID127_SYSCFG_773 0x124
static struct reset_syscfg stid127_reset = {
.offset_rst = STID127_SYSCFG_773,
.mask_rst = BIT(0),
.offset_rst_msk = STID127_SYSCFG_700,
.mask_rst_msk = BIT(8)
};
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,stih415-restart",
.data = (void *)&stih415_reset,
}, {
.compatible = "st,stih416-restart",
.data = (void *)&stih416_reset,
}, {
.compatible = "st,stih407-restart",
.data = (void *)&stih407_reset,
}, {
.compatible = "st,stid127-restart",
.data = (void *)&stid127_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");
