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path: root/drivers/watchdog/bcm47xx_wdt.c
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Diffstat (limited to 'drivers/watchdog/bcm47xx_wdt.c')
-rw-r--r--drivers/watchdog/bcm47xx_wdt.c275
1 files changed, 275 insertions, 0 deletions
diff --git a/drivers/watchdog/bcm47xx_wdt.c b/drivers/watchdog/bcm47xx_wdt.c
new file mode 100644
index 000000000..b28a072ab
--- /dev/null
+++ b/drivers/watchdog/bcm47xx_wdt.c
@@ -0,0 +1,275 @@
+/*
+ * Watchdog driver for Broadcom BCM47XX
+ *
+ * Copyright (C) 2008 Aleksandar Radovanovic <biblbroks@sezampro.rs>
+ * Copyright (C) 2009 Matthieu CASTET <castet.matthieu@free.fr>
+ * Copyright (C) 2012-2013 Hauke Mehrtens <hauke@hauke-m.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/bcm47xx_wdt.h>
+#include <linux/bitops.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
+#include <linux/timer.h>
+#include <linux/jiffies.h>
+
+#define DRV_NAME "bcm47xx_wdt"
+
+#define WDT_DEFAULT_TIME 30 /* seconds */
+#define WDT_SOFTTIMER_MAX 255 /* seconds */
+#define WDT_SOFTTIMER_THRESHOLD 60 /* seconds */
+
+static int timeout = WDT_DEFAULT_TIME;
+static bool nowayout = WATCHDOG_NOWAYOUT;
+
+module_param(timeout, int, 0);
+MODULE_PARM_DESC(timeout, "Watchdog time in seconds. (default="
+ __MODULE_STRING(WDT_DEFAULT_TIME) ")");
+
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout,
+ "Watchdog cannot be stopped once started (default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static inline struct bcm47xx_wdt *bcm47xx_wdt_get(struct watchdog_device *wdd)
+{
+ return container_of(wdd, struct bcm47xx_wdt, wdd);
+}
+
+static int bcm47xx_wdt_hard_keepalive(struct watchdog_device *wdd)
+{
+ struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+ wdt->timer_set_ms(wdt, wdd->timeout * 1000);
+
+ return 0;
+}
+
+static int bcm47xx_wdt_hard_start(struct watchdog_device *wdd)
+{
+ return 0;
+}
+
+static int bcm47xx_wdt_hard_stop(struct watchdog_device *wdd)
+{
+ struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+ wdt->timer_set(wdt, 0);
+
+ return 0;
+}
+
+static int bcm47xx_wdt_hard_set_timeout(struct watchdog_device *wdd,
+ unsigned int new_time)
+{
+ struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+ u32 max_timer = wdt->max_timer_ms;
+
+ if (new_time < 1 || new_time > max_timer / 1000) {
+ pr_warn("timeout value must be 1<=x<=%d, using %d\n",
+ max_timer / 1000, new_time);
+ return -EINVAL;
+ }
+
+ wdd->timeout = new_time;
+ return 0;
+}
+
+static struct watchdog_ops bcm47xx_wdt_hard_ops = {
+ .owner = THIS_MODULE,
+ .start = bcm47xx_wdt_hard_start,
+ .stop = bcm47xx_wdt_hard_stop,
+ .ping = bcm47xx_wdt_hard_keepalive,
+ .set_timeout = bcm47xx_wdt_hard_set_timeout,
+};
+
+static void bcm47xx_wdt_soft_timer_tick(unsigned long data)
+{
+ struct bcm47xx_wdt *wdt = (struct bcm47xx_wdt *)data;
+ u32 next_tick = min(wdt->wdd.timeout * 1000, wdt->max_timer_ms);
+
+ if (!atomic_dec_and_test(&wdt->soft_ticks)) {
+ wdt->timer_set_ms(wdt, next_tick);
+ mod_timer(&wdt->soft_timer, jiffies + HZ);
+ } else {
+ pr_crit("Watchdog will fire soon!!!\n");
+ }
+}
+
+static int bcm47xx_wdt_soft_keepalive(struct watchdog_device *wdd)
+{
+ struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+ atomic_set(&wdt->soft_ticks, wdd->timeout);
+
+ return 0;
+}
+
+static int bcm47xx_wdt_soft_start(struct watchdog_device *wdd)
+{
+ struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+ bcm47xx_wdt_soft_keepalive(wdd);
+ bcm47xx_wdt_soft_timer_tick((unsigned long)wdt);
+
+ return 0;
+}
+
+static int bcm47xx_wdt_soft_stop(struct watchdog_device *wdd)
+{
+ struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
+
+ del_timer_sync(&wdt->soft_timer);
+ wdt->timer_set(wdt, 0);
+
+ return 0;
+}
+
+static int bcm47xx_wdt_soft_set_timeout(struct watchdog_device *wdd,
+ unsigned int new_time)
+{
+ if (new_time < 1 || new_time > WDT_SOFTTIMER_MAX) {
+ pr_warn("timeout value must be 1<=x<=%d, using %d\n",
+ WDT_SOFTTIMER_MAX, new_time);
+ return -EINVAL;
+ }
+
+ wdd->timeout = new_time;
+ return 0;
+}
+
+static const struct watchdog_info bcm47xx_wdt_info = {
+ .identity = DRV_NAME,
+ .options = WDIOF_SETTIMEOUT |
+ WDIOF_KEEPALIVEPING |
+ WDIOF_MAGICCLOSE,
+};
+
+static int bcm47xx_wdt_notify_sys(struct notifier_block *this,
+ unsigned long code, void *unused)
+{
+ struct bcm47xx_wdt *wdt;
+
+ wdt = container_of(this, struct bcm47xx_wdt, notifier);
+ if (code == SYS_DOWN || code == SYS_HALT)
+ wdt->wdd.ops->stop(&wdt->wdd);
+ return NOTIFY_DONE;
+}
+
+static int bcm47xx_wdt_restart(struct notifier_block *this, unsigned long mode,
+ void *cmd)
+{
+ struct bcm47xx_wdt *wdt;
+
+ wdt = container_of(this, struct bcm47xx_wdt, restart_handler);
+ wdt->timer_set(wdt, 1);
+
+ return NOTIFY_DONE;
+}
+
+static struct watchdog_ops bcm47xx_wdt_soft_ops = {
+ .owner = THIS_MODULE,
+ .start = bcm47xx_wdt_soft_start,
+ .stop = bcm47xx_wdt_soft_stop,
+ .ping = bcm47xx_wdt_soft_keepalive,
+ .set_timeout = bcm47xx_wdt_soft_set_timeout,
+};
+
+static int bcm47xx_wdt_probe(struct platform_device *pdev)
+{
+ int ret;
+ bool soft;
+ struct bcm47xx_wdt *wdt = dev_get_platdata(&pdev->dev);
+
+ if (!wdt)
+ return -ENXIO;
+
+ soft = wdt->max_timer_ms < WDT_SOFTTIMER_THRESHOLD * 1000;
+
+ if (soft) {
+ wdt->wdd.ops = &bcm47xx_wdt_soft_ops;
+ setup_timer(&wdt->soft_timer, bcm47xx_wdt_soft_timer_tick,
+ (long unsigned int)wdt);
+ } else {
+ wdt->wdd.ops = &bcm47xx_wdt_hard_ops;
+ }
+
+ wdt->wdd.info = &bcm47xx_wdt_info;
+ wdt->wdd.timeout = WDT_DEFAULT_TIME;
+ ret = wdt->wdd.ops->set_timeout(&wdt->wdd, timeout);
+ if (ret)
+ goto err_timer;
+ watchdog_set_nowayout(&wdt->wdd, nowayout);
+
+ wdt->notifier.notifier_call = &bcm47xx_wdt_notify_sys;
+
+ ret = register_reboot_notifier(&wdt->notifier);
+ if (ret)
+ goto err_timer;
+
+ wdt->restart_handler.notifier_call = &bcm47xx_wdt_restart;
+ wdt->restart_handler.priority = 64;
+ ret = register_restart_handler(&wdt->restart_handler);
+ if (ret)
+ goto err_notifier;
+
+ ret = watchdog_register_device(&wdt->wdd);
+ if (ret)
+ goto err_handler;
+
+ dev_info(&pdev->dev, "BCM47xx Watchdog Timer enabled (%d seconds%s%s)\n",
+ timeout, nowayout ? ", nowayout" : "",
+ soft ? ", Software Timer" : "");
+ return 0;
+
+err_handler:
+ unregister_restart_handler(&wdt->restart_handler);
+err_notifier:
+ unregister_reboot_notifier(&wdt->notifier);
+err_timer:
+ if (soft)
+ del_timer_sync(&wdt->soft_timer);
+
+ return ret;
+}
+
+static int bcm47xx_wdt_remove(struct platform_device *pdev)
+{
+ struct bcm47xx_wdt *wdt = dev_get_platdata(&pdev->dev);
+
+ if (!wdt)
+ return -ENXIO;
+
+ watchdog_unregister_device(&wdt->wdd);
+ unregister_reboot_notifier(&wdt->notifier);
+
+ return 0;
+}
+
+static struct platform_driver bcm47xx_wdt_driver = {
+ .driver = {
+ .name = "bcm47xx-wdt",
+ },
+ .probe = bcm47xx_wdt_probe,
+ .remove = bcm47xx_wdt_remove,
+};
+
+module_platform_driver(bcm47xx_wdt_driver);
+
+MODULE_AUTHOR("Aleksandar Radovanovic");
+MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
+MODULE_DESCRIPTION("Watchdog driver for Broadcom BCM47xx");
+MODULE_LICENSE("GPL");