/* * 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; wdt->wdd.parent = &pdev->dev; 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");