x86/efistub: Avoid placing the kernel below LOAD_PHYSICAL_ADDR
[platform/kernel/linux-starfive.git] / drivers / watchdog / twl4030_wdt.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) Nokia Corporation
4  *
5  * Written by Timo Kokkonen <timo.t.kokkonen at nokia.com>
6  */
7
8 #include <linux/module.h>
9 #include <linux/types.h>
10 #include <linux/slab.h>
11 #include <linux/kernel.h>
12 #include <linux/mod_devicetable.h>
13 #include <linux/watchdog.h>
14 #include <linux/platform_device.h>
15 #include <linux/mfd/twl.h>
16
17 #define TWL4030_WATCHDOG_CFG_REG_OFFS   0x3
18
19 static bool nowayout = WATCHDOG_NOWAYOUT;
20 module_param(nowayout, bool, 0);
21 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
22         "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
23
24 static int twl4030_wdt_write(unsigned char val)
25 {
26         return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val,
27                                         TWL4030_WATCHDOG_CFG_REG_OFFS);
28 }
29
30 static int twl4030_wdt_start(struct watchdog_device *wdt)
31 {
32         return twl4030_wdt_write(wdt->timeout + 1);
33 }
34
35 static int twl4030_wdt_stop(struct watchdog_device *wdt)
36 {
37         return twl4030_wdt_write(0);
38 }
39
40 static int twl4030_wdt_set_timeout(struct watchdog_device *wdt,
41                                    unsigned int timeout)
42 {
43         wdt->timeout = timeout;
44         return 0;
45 }
46
47 static const struct watchdog_info twl4030_wdt_info = {
48         .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
49         .identity = "TWL4030 Watchdog",
50 };
51
52 static const struct watchdog_ops twl4030_wdt_ops = {
53         .owner          = THIS_MODULE,
54         .start          = twl4030_wdt_start,
55         .stop           = twl4030_wdt_stop,
56         .set_timeout    = twl4030_wdt_set_timeout,
57 };
58
59 static int twl4030_wdt_probe(struct platform_device *pdev)
60 {
61         struct device *dev = &pdev->dev;
62         struct watchdog_device *wdt;
63
64         wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
65         if (!wdt)
66                 return -ENOMEM;
67
68         wdt->info               = &twl4030_wdt_info;
69         wdt->ops                = &twl4030_wdt_ops;
70         wdt->status             = 0;
71         wdt->timeout            = 30;
72         wdt->min_timeout        = 1;
73         wdt->max_timeout        = 30;
74         wdt->parent = dev;
75
76         watchdog_set_nowayout(wdt, nowayout);
77         platform_set_drvdata(pdev, wdt);
78
79         twl4030_wdt_stop(wdt);
80
81         return devm_watchdog_register_device(dev, wdt);
82 }
83
84 static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
85 {
86         struct watchdog_device *wdt = platform_get_drvdata(pdev);
87         if (watchdog_active(wdt))
88                 return twl4030_wdt_stop(wdt);
89
90         return 0;
91 }
92
93 static int twl4030_wdt_resume(struct platform_device *pdev)
94 {
95         struct watchdog_device *wdt = platform_get_drvdata(pdev);
96         if (watchdog_active(wdt))
97                 return twl4030_wdt_start(wdt);
98
99         return 0;
100 }
101
102 static const struct of_device_id twl_wdt_of_match[] = {
103         { .compatible = "ti,twl4030-wdt", },
104         { },
105 };
106 MODULE_DEVICE_TABLE(of, twl_wdt_of_match);
107
108 static struct platform_driver twl4030_wdt_driver = {
109         .probe          = twl4030_wdt_probe,
110         .suspend        = pm_ptr(twl4030_wdt_suspend),
111         .resume         = pm_ptr(twl4030_wdt_resume),
112         .driver         = {
113                 .name           = "twl4030_wdt",
114                 .of_match_table = twl_wdt_of_match,
115         },
116 };
117
118 module_platform_driver(twl4030_wdt_driver);
119
120 MODULE_AUTHOR("Nokia Corporation");
121 MODULE_LICENSE("GPL");
122 MODULE_ALIAS("platform:twl4030_wdt");
123