/*
* 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/init.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 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;
ret = watchdog_register_device(&wdt->wdd);
if (ret)
goto err_notifier;
dev_info(&pdev->dev, "BCM47xx Watchdog Timer enabled (%d seconds%s%s)\n",
timeout, nowayout ? ", nowayout" : "",
soft ? ", Software Timer" : "");
return 0;
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 = {
.owner = THIS_MODULE,
.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");
