1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) Nokia Corporation
5 * Written by Timo Kokkonen <timo.t.kokkonen at nokia.com>
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>
17 #define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3
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) ")");
24 static int twl4030_wdt_write(unsigned char val)
26 return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val,
27 TWL4030_WATCHDOG_CFG_REG_OFFS);
30 static int twl4030_wdt_start(struct watchdog_device *wdt)
32 return twl4030_wdt_write(wdt->timeout + 1);
35 static int twl4030_wdt_stop(struct watchdog_device *wdt)
37 return twl4030_wdt_write(0);
40 static int twl4030_wdt_set_timeout(struct watchdog_device *wdt,
43 wdt->timeout = timeout;
47 static const struct watchdog_info twl4030_wdt_info = {
48 .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
49 .identity = "TWL4030 Watchdog",
52 static const struct watchdog_ops twl4030_wdt_ops = {
54 .start = twl4030_wdt_start,
55 .stop = twl4030_wdt_stop,
56 .set_timeout = twl4030_wdt_set_timeout,
59 static int twl4030_wdt_probe(struct platform_device *pdev)
61 struct device *dev = &pdev->dev;
62 struct watchdog_device *wdt;
64 wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
68 wdt->info = &twl4030_wdt_info;
69 wdt->ops = &twl4030_wdt_ops;
73 wdt->max_timeout = 30;
76 watchdog_set_nowayout(wdt, nowayout);
77 platform_set_drvdata(pdev, wdt);
79 twl4030_wdt_stop(wdt);
81 return devm_watchdog_register_device(dev, wdt);
84 static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
86 struct watchdog_device *wdt = platform_get_drvdata(pdev);
87 if (watchdog_active(wdt))
88 return twl4030_wdt_stop(wdt);
93 static int twl4030_wdt_resume(struct platform_device *pdev)
95 struct watchdog_device *wdt = platform_get_drvdata(pdev);
96 if (watchdog_active(wdt))
97 return twl4030_wdt_start(wdt);
102 static const struct of_device_id twl_wdt_of_match[] = {
103 { .compatible = "ti,twl4030-wdt", },
106 MODULE_DEVICE_TABLE(of, twl_wdt_of_match);
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),
113 .name = "twl4030_wdt",
114 .of_match_table = twl_wdt_of_match,
118 module_platform_driver(twl4030_wdt_driver);
120 MODULE_AUTHOR("Nokia Corporation");
121 MODULE_LICENSE("GPL");
122 MODULE_ALIAS("platform:twl4030_wdt");