2 * Copyright (C) Nokia Corporation
4 * Written by Timo Kokkonen <timo.t.kokkonen at nokia.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 #include <linux/module.h>
22 #include <linux/types.h>
23 #include <linux/slab.h>
24 #include <linux/kernel.h>
25 #include <linux/watchdog.h>
26 #include <linux/platform_device.h>
27 #include <linux/i2c/twl.h>
29 #define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3
31 static bool nowayout = WATCHDOG_NOWAYOUT;
32 module_param(nowayout, bool, 0);
33 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
34 "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
36 static int twl4030_wdt_write(unsigned char val)
38 return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val,
39 TWL4030_WATCHDOG_CFG_REG_OFFS);
42 static int twl4030_wdt_start(struct watchdog_device *wdt)
44 return twl4030_wdt_write(wdt->timeout + 1);
47 static int twl4030_wdt_stop(struct watchdog_device *wdt)
49 return twl4030_wdt_write(0);
52 static int twl4030_wdt_set_timeout(struct watchdog_device *wdt,
55 wdt->timeout = timeout;
59 static const struct watchdog_info twl4030_wdt_info = {
60 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
61 .identity = "TWL4030 Watchdog",
64 static const struct watchdog_ops twl4030_wdt_ops = {
66 .start = twl4030_wdt_start,
67 .stop = twl4030_wdt_stop,
68 .set_timeout = twl4030_wdt_set_timeout,
71 static int twl4030_wdt_probe(struct platform_device *pdev)
74 struct watchdog_device *wdt;
76 wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
80 wdt->info = &twl4030_wdt_info;
81 wdt->ops = &twl4030_wdt_ops;
85 wdt->max_timeout = 30;
87 watchdog_set_nowayout(wdt, nowayout);
88 platform_set_drvdata(pdev, wdt);
90 twl4030_wdt_stop(wdt);
92 ret = watchdog_register_device(wdt);
99 static int twl4030_wdt_remove(struct platform_device *pdev)
101 struct watchdog_device *wdt = platform_get_drvdata(pdev);
103 watchdog_unregister_device(wdt);
109 static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
111 struct watchdog_device *wdt = platform_get_drvdata(pdev);
112 if (watchdog_active(wdt))
113 return twl4030_wdt_stop(wdt);
118 static int twl4030_wdt_resume(struct platform_device *pdev)
120 struct watchdog_device *wdt = platform_get_drvdata(pdev);
121 if (watchdog_active(wdt))
122 return twl4030_wdt_start(wdt);
127 #define twl4030_wdt_suspend NULL
128 #define twl4030_wdt_resume NULL
131 static const struct of_device_id twl_wdt_of_match[] = {
132 { .compatible = "ti,twl4030-wdt", },
135 MODULE_DEVICE_TABLE(of, twl_wdt_of_match);
137 static struct platform_driver twl4030_wdt_driver = {
138 .probe = twl4030_wdt_probe,
139 .remove = twl4030_wdt_remove,
140 .suspend = twl4030_wdt_suspend,
141 .resume = twl4030_wdt_resume,
143 .owner = THIS_MODULE,
144 .name = "twl4030_wdt",
145 .of_match_table = twl_wdt_of_match,
149 module_platform_driver(twl4030_wdt_driver);
151 MODULE_AUTHOR("Nokia Corporation");
152 MODULE_LICENSE("GPL");
153 MODULE_ALIAS("platform:twl4030_wdt");