acrn-kernel/drivers/power/reset/syscon-reboot-mode.c

91 lines
2.4 KiB
C

/*
* Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <linux/reboot-mode.h>
struct syscon_reboot_mode {
struct regmap *map;
struct reboot_mode_driver reboot;
u32 offset;
u32 mask;
};
static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot,
unsigned int magic)
{
struct syscon_reboot_mode *syscon_rbm;
int ret;
syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot);
ret = regmap_update_bits(syscon_rbm->map, syscon_rbm->offset,
syscon_rbm->mask, magic);
if (ret < 0)
dev_err(reboot->dev, "update reboot mode bits failed\n");
return ret;
}
static int syscon_reboot_mode_probe(struct platform_device *pdev)
{
int ret;
struct syscon_reboot_mode *syscon_rbm;
syscon_rbm = devm_kzalloc(&pdev->dev, sizeof(*syscon_rbm), GFP_KERNEL);
if (!syscon_rbm)
return -ENOMEM;
syscon_rbm->reboot.dev = &pdev->dev;
syscon_rbm->reboot.write = syscon_reboot_mode_write;
syscon_rbm->mask = 0xffffffff;
syscon_rbm->map = syscon_node_to_regmap(pdev->dev.parent->of_node);
if (IS_ERR(syscon_rbm->map))
return PTR_ERR(syscon_rbm->map);
if (of_property_read_u32(pdev->dev.of_node, "offset",
&syscon_rbm->offset))
return -EINVAL;
of_property_read_u32(pdev->dev.of_node, "mask", &syscon_rbm->mask);
ret = devm_reboot_mode_register(&pdev->dev, &syscon_rbm->reboot);
if (ret)
dev_err(&pdev->dev, "can't register reboot mode\n");
return ret;
}
static const struct of_device_id syscon_reboot_mode_of_match[] = {
{ .compatible = "syscon-reboot-mode" },
{}
};
MODULE_DEVICE_TABLE(of, syscon_reboot_mode_of_match);
static struct platform_driver syscon_reboot_mode_driver = {
.probe = syscon_reboot_mode_probe,
.driver = {
.name = "syscon-reboot-mode",
.of_match_table = syscon_reboot_mode_of_match,
},
};
module_platform_driver(syscon_reboot_mode_driver);
MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com");
MODULE_DESCRIPTION("SYSCON reboot mode driver");
MODULE_LICENSE("GPL v2");