tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Renesas R-Mobile Reset Driver
4 *
5 * Copyright (C) 2014 Glider bvba
6 */
7
8#include <linux/io.h>
9#include <linux/module.h>
10#include <linux/notifier.h>
11#include <linux/of_address.h>
12#include <linux/platform_device.h>
13#include <linux/printk.h>
14#include <linux/reboot.h>
15
16/* SYSC Register Bank 2 */
17#define RESCNT2 0x20 /* Reset Control Register 2 */
18
19/* Reset Control Register 2 */
20#define RESCNT2_PRES 0x80000000 /* Soft power-on reset */
21
22static int rmobile_reset_handler(struct sys_off_data *data)
23{
24 void __iomem *sysc_base2 = (void __iomem *)data->cb_data;
25
26 /* Let's assume we have acquired the HPB semaphore */
27 writel(RESCNT2_PRES, sysc_base2 + RESCNT2);
28
29 return NOTIFY_DONE;
30}
31
32static int rmobile_reset_probe(struct platform_device *pdev)
33{
34 void __iomem *sysc_base2;
35 int error;
36
37 sysc_base2 = devm_platform_ioremap_resource(pdev, 1);
38 if (IS_ERR(sysc_base2))
39 return PTR_ERR(sysc_base2);
40
41 error = devm_register_sys_off_handler(&pdev->dev,
42 SYS_OFF_MODE_RESTART,
43 SYS_OFF_PRIO_HIGH,
44 rmobile_reset_handler,
45 (__force void *)sysc_base2);
46 if (error) {
47 dev_err(&pdev->dev,
48 "cannot register restart handler (err=%d)\n", error);
49 return error;
50 }
51
52 return 0;
53}
54
55static const struct of_device_id rmobile_reset_of_match[] = {
56 { .compatible = "renesas,sysc-rmobile", },
57 { /* sentinel */ }
58};
59MODULE_DEVICE_TABLE(of, rmobile_reset_of_match);
60
61static struct platform_driver rmobile_reset_driver = {
62 .probe = rmobile_reset_probe,
63 .driver = {
64 .name = "rmobile_reset",
65 .of_match_table = rmobile_reset_of_match,
66 },
67};
68
69module_platform_driver(rmobile_reset_driver);
70
71MODULE_DESCRIPTION("Renesas R-Mobile Reset Driver");
72MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
73MODULE_LICENSE("GPL v2");