diff options
Diffstat (limited to 'drivers/watchdog/bcm47xx_wdt.c')
| -rw-r--r-- | drivers/watchdog/bcm47xx_wdt.c | 243 |
1 files changed, 243 insertions, 0 deletions
diff --git a/drivers/watchdog/bcm47xx_wdt.c b/drivers/watchdog/bcm47xx_wdt.c new file mode 100644 index 000000000..05425c1df --- /dev/null +++ b/drivers/watchdog/bcm47xx_wdt.c @@ -0,0 +1,243 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * 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> + * + */ + +#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/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 int bcm47xx_wdt_restart(struct watchdog_device *wdd, + unsigned long action, void *data) +{ + struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd); + + wdt->timer_set(wdt, 1); + + return 0; +} + +static const 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, + .restart = bcm47xx_wdt_restart, +}; + +static void bcm47xx_wdt_soft_timer_tick(struct timer_list *t) +{ + struct bcm47xx_wdt *wdt = from_timer(wdt, t, soft_timer); + 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(&wdt->soft_timer); + + 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 const 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, + .restart = bcm47xx_wdt_restart, +}; + +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; + timer_setup(&wdt->soft_timer, bcm47xx_wdt_soft_timer_tick, 0); + } 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); + watchdog_set_restart_priority(&wdt->wdd, 64); + watchdog_stop_on_reboot(&wdt->wdd); + + ret = watchdog_register_device(&wdt->wdd); + if (ret) + goto err_timer; + + dev_info(&pdev->dev, "BCM47xx Watchdog Timer enabled (%d seconds%s%s)\n", + timeout, nowayout ? ", nowayout" : "", + soft ? ", Software Timer" : ""); + return 0; + +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); + + watchdog_unregister_device(&wdt->wdd); + + 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"); |