Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / watchdog / stmp3xxx_rtc_wdt.c
diff --git a/kernel/drivers/watchdog/stmp3xxx_rtc_wdt.c b/kernel/drivers/watchdog/stmp3xxx_rtc_wdt.c
new file mode 100644 (file)
index 0000000..e7f0d5b
--- /dev/null
@@ -0,0 +1,132 @@
+/*
+ * Watchdog driver for the RTC based watchdog in STMP3xxx and i.MX23/28
+ *
+ * Author: Wolfram Sang <kernel@pengutronix.de>
+ *
+ * Copyright (C) 2011-12 Wolfram Sang, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/watchdog.h>
+#include <linux/platform_device.h>
+#include <linux/stmp3xxx_rtc_wdt.h>
+
+#define WDOG_TICK_RATE 1000 /* 1 kHz clock */
+#define STMP3XXX_DEFAULT_TIMEOUT 19
+#define STMP3XXX_MAX_TIMEOUT (UINT_MAX / WDOG_TICK_RATE)
+
+static int heartbeat = STMP3XXX_DEFAULT_TIMEOUT;
+module_param(heartbeat, uint, 0);
+MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat period in seconds from 1 to "
+                __MODULE_STRING(STMP3XXX_MAX_TIMEOUT) ", default "
+                __MODULE_STRING(STMP3XXX_DEFAULT_TIMEOUT));
+
+static int wdt_start(struct watchdog_device *wdd)
+{
+       struct device *dev = watchdog_get_drvdata(wdd);
+       struct stmp3xxx_wdt_pdata *pdata = dev_get_platdata(dev);
+
+       pdata->wdt_set_timeout(dev->parent, wdd->timeout * WDOG_TICK_RATE);
+       return 0;
+}
+
+static int wdt_stop(struct watchdog_device *wdd)
+{
+       struct device *dev = watchdog_get_drvdata(wdd);
+       struct stmp3xxx_wdt_pdata *pdata = dev_get_platdata(dev);
+
+       pdata->wdt_set_timeout(dev->parent, 0);
+       return 0;
+}
+
+static int wdt_set_timeout(struct watchdog_device *wdd, unsigned new_timeout)
+{
+       wdd->timeout = new_timeout;
+       return wdt_start(wdd);
+}
+
+static const struct watchdog_info stmp3xxx_wdt_ident = {
+       .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+       .identity = "STMP3XXX RTC Watchdog",
+};
+
+static const struct watchdog_ops stmp3xxx_wdt_ops = {
+       .owner = THIS_MODULE,
+       .start = wdt_start,
+       .stop = wdt_stop,
+       .set_timeout = wdt_set_timeout,
+};
+
+static struct watchdog_device stmp3xxx_wdd = {
+       .info = &stmp3xxx_wdt_ident,
+       .ops = &stmp3xxx_wdt_ops,
+       .min_timeout = 1,
+       .max_timeout = STMP3XXX_MAX_TIMEOUT,
+       .status = WATCHDOG_NOWAYOUT_INIT_STATUS,
+};
+
+static int stmp3xxx_wdt_probe(struct platform_device *pdev)
+{
+       int ret;
+
+       watchdog_set_drvdata(&stmp3xxx_wdd, &pdev->dev);
+
+       stmp3xxx_wdd.timeout = clamp_t(unsigned, heartbeat, 1, STMP3XXX_MAX_TIMEOUT);
+
+       ret = watchdog_register_device(&stmp3xxx_wdd);
+       if (ret < 0) {
+               dev_err(&pdev->dev, "cannot register watchdog device\n");
+               return ret;
+       }
+
+       dev_info(&pdev->dev, "initialized watchdog with heartbeat %ds\n",
+                       stmp3xxx_wdd.timeout);
+       return 0;
+}
+
+static int stmp3xxx_wdt_remove(struct platform_device *pdev)
+{
+       watchdog_unregister_device(&stmp3xxx_wdd);
+       return 0;
+}
+
+static int __maybe_unused stmp3xxx_wdt_suspend(struct device *dev)
+{
+       struct watchdog_device *wdd = &stmp3xxx_wdd;
+
+       if (watchdog_active(wdd))
+               return wdt_stop(wdd);
+
+       return 0;
+}
+
+static int __maybe_unused stmp3xxx_wdt_resume(struct device *dev)
+{
+       struct watchdog_device *wdd = &stmp3xxx_wdd;
+
+       if (watchdog_active(wdd))
+               return wdt_start(wdd);
+
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(stmp3xxx_wdt_pm_ops,
+                        stmp3xxx_wdt_suspend, stmp3xxx_wdt_resume);
+
+static struct platform_driver stmp3xxx_wdt_driver = {
+       .driver = {
+               .name = "stmp3xxx_rtc_wdt",
+               .pm = &stmp3xxx_wdt_pm_ops,
+       },
+       .probe = stmp3xxx_wdt_probe,
+       .remove = stmp3xxx_wdt_remove,
+};
+module_platform_driver(stmp3xxx_wdt_driver);
+
+MODULE_DESCRIPTION("STMP3XXX RTC Watchdog Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");