// SPDX-License-Identifier: GPL-2.0 /* * Renesas R-Mobile Reset Driver * * Copyright (C) 2014 Glider bvba */ #include <linux/io.h> #include <linux/module.h> #include <linux/notifier.h> #include <linux/of_address.h> #include <linux/platform_device.h> #include <linux/printk.h> #include <linux/reboot.h> /* SYSC Register Bank 2 */ #define RESCNT2 0x20 /* Reset Control Register 2 */ /* Reset Control Register 2 */ #define RESCNT2_PRES 0x80000000 /* Soft power-on reset */ static void __iomem *sysc_base2; static int rmobile_reset_handler(struct notifier_block *this, unsigned long mode, void *cmd) { pr_debug("%s %lu\n", __func__, mode); /* Let's assume we have acquired the HPB semaphore */ writel(RESCNT2_PRES, sysc_base2 + RESCNT2); return NOTIFY_DONE; } static struct notifier_block rmobile_reset_nb = { .notifier_call = rmobile_reset_handler, .priority = 192, }; static int rmobile_reset_probe(struct platform_device *pdev) { int error; sysc_base2 = of_iomap(pdev->dev.of_node, 1); if (!sysc_base2) return -ENODEV; error = register_restart_handler(&rmobile_reset_nb); if (error) { dev_err(&pdev->dev, "cannot register restart handler (err=%d)\n", error); goto fail_unmap; } return 0; fail_unmap: iounmap(sysc_base2); return error; } static int rmobile_reset_remove(struct platform_device *pdev) { unregister_restart_handler(&rmobile_reset_nb); iounmap(sysc_base2); return 0; } static const struct of_device_id rmobile_reset_of_match[] = { { .compatible = "renesas,sysc-rmobile", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, rmobile_reset_of_match); static struct platform_driver rmobile_reset_driver = { .probe = rmobile_reset_probe, .remove = rmobile_reset_remove, .driver = { .name = "rmobile_reset", .of_match_table = rmobile_reset_of_match, }, }; module_platform_driver(rmobile_reset_driver); MODULE_DESCRIPTION("Renesas R-Mobile Reset Driver"); MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>"); MODULE_LICENSE("GPL v2");