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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd4 */5 6#include <linux/init.h>7#include <linux/module.h>8#include <linux/kernel.h>9#include <linux/of.h>10#include <linux/platform_device.h>11#include <linux/reboot.h>12#include <linux/regmap.h>13#include <linux/mfd/syscon.h>14#include <linux/reboot-mode.h>15 16struct syscon_reboot_mode {17 struct regmap *map;18 struct reboot_mode_driver reboot;19 u32 offset;20 u32 mask;21};22 23static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot,24 unsigned int magic)25{26 struct syscon_reboot_mode *syscon_rbm;27 int ret;28 29 syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot);30 31 ret = regmap_update_bits(syscon_rbm->map, syscon_rbm->offset,32 syscon_rbm->mask, magic);33 if (ret < 0)34 dev_err(reboot->dev, "update reboot mode bits failed\n");35 36 return ret;37}38 39static int syscon_reboot_mode_probe(struct platform_device *pdev)40{41 int ret;42 struct syscon_reboot_mode *syscon_rbm;43 44 syscon_rbm = devm_kzalloc(&pdev->dev, sizeof(*syscon_rbm), GFP_KERNEL);45 if (!syscon_rbm)46 return -ENOMEM;47 48 syscon_rbm->reboot.dev = &pdev->dev;49 syscon_rbm->reboot.write = syscon_reboot_mode_write;50 syscon_rbm->mask = 0xffffffff;51 52 syscon_rbm->map = syscon_node_to_regmap(pdev->dev.parent->of_node);53 if (IS_ERR(syscon_rbm->map))54 return PTR_ERR(syscon_rbm->map);55 56 if (of_property_read_u32(pdev->dev.of_node, "offset",57 &syscon_rbm->offset))58 return -EINVAL;59 60 of_property_read_u32(pdev->dev.of_node, "mask", &syscon_rbm->mask);61 62 ret = devm_reboot_mode_register(&pdev->dev, &syscon_rbm->reboot);63 if (ret)64 dev_err(&pdev->dev, "can't register reboot mode\n");65 66 return ret;67}68 69static const struct of_device_id syscon_reboot_mode_of_match[] = {70 { .compatible = "syscon-reboot-mode" },71 {}72};73MODULE_DEVICE_TABLE(of, syscon_reboot_mode_of_match);74 75static struct platform_driver syscon_reboot_mode_driver = {76 .probe = syscon_reboot_mode_probe,77 .driver = {78 .name = "syscon-reboot-mode",79 .of_match_table = syscon_reboot_mode_of_match,80 },81};82module_platform_driver(syscon_reboot_mode_driver);83 84MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com");85MODULE_DESCRIPTION("SYSCON reboot mode driver");86MODULE_LICENSE("GPL v2");87