linux/drivers/watchdog/retu_wdt.c
Guenter Roeck d017327893 watchdog: convert remaining drivers to use SPDX license identifier
This gets rid of the unnecessary license boilerplate, and avoids
having to deal with individual patches one by one.

No functional changes.

Reviewed-by: Jerry Hoemann <jerry.hoemann@hpe.com>
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
2019-07-08 20:35:11 +02:00

171 lines
4.1 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Retu watchdog driver
*
* Copyright (C) 2004, 2005 Nokia Corporation
*
* Based on code written by Amit Kucheria and Michael Buesch.
* Rewritten by Aaro Koskinen.
*/
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mfd/retu.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
/* Watchdog timer values in seconds */
#define RETU_WDT_MAX_TIMER 63
struct retu_wdt_dev {
struct retu_dev *rdev;
struct device *dev;
struct delayed_work ping_work;
};
/*
* Since Retu watchdog cannot be disabled in hardware, we must kick it
* with a timer until userspace watchdog software takes over. If
* CONFIG_WATCHDOG_NOWAYOUT is set, we never start the feeding.
*/
static void retu_wdt_ping_enable(struct retu_wdt_dev *wdev)
{
retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER);
schedule_delayed_work(&wdev->ping_work,
round_jiffies_relative(RETU_WDT_MAX_TIMER * HZ / 2));
}
static void retu_wdt_ping_disable(struct retu_wdt_dev *wdev)
{
retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER);
cancel_delayed_work_sync(&wdev->ping_work);
}
static void retu_wdt_ping_work(struct work_struct *work)
{
struct retu_wdt_dev *wdev = container_of(to_delayed_work(work),
struct retu_wdt_dev, ping_work);
retu_wdt_ping_enable(wdev);
}
static int retu_wdt_start(struct watchdog_device *wdog)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
retu_wdt_ping_disable(wdev);
return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
}
static int retu_wdt_stop(struct watchdog_device *wdog)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
retu_wdt_ping_enable(wdev);
return 0;
}
static int retu_wdt_ping(struct watchdog_device *wdog)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
}
static int retu_wdt_set_timeout(struct watchdog_device *wdog,
unsigned int timeout)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
wdog->timeout = timeout;
return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
}
static const struct watchdog_info retu_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
.identity = "Retu watchdog",
};
static const struct watchdog_ops retu_wdt_ops = {
.owner = THIS_MODULE,
.start = retu_wdt_start,
.stop = retu_wdt_stop,
.ping = retu_wdt_ping,
.set_timeout = retu_wdt_set_timeout,
};
static int retu_wdt_probe(struct platform_device *pdev)
{
struct retu_dev *rdev = dev_get_drvdata(pdev->dev.parent);
bool nowayout = WATCHDOG_NOWAYOUT;
struct watchdog_device *retu_wdt;
struct retu_wdt_dev *wdev;
int ret;
retu_wdt = devm_kzalloc(&pdev->dev, sizeof(*retu_wdt), GFP_KERNEL);
if (!retu_wdt)
return -ENOMEM;
wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL);
if (!wdev)
return -ENOMEM;
retu_wdt->info = &retu_wdt_info;
retu_wdt->ops = &retu_wdt_ops;
retu_wdt->timeout = RETU_WDT_MAX_TIMER;
retu_wdt->min_timeout = 0;
retu_wdt->max_timeout = RETU_WDT_MAX_TIMER;
retu_wdt->parent = &pdev->dev;
watchdog_set_drvdata(retu_wdt, wdev);
watchdog_set_nowayout(retu_wdt, nowayout);
wdev->rdev = rdev;
wdev->dev = &pdev->dev;
INIT_DELAYED_WORK(&wdev->ping_work, retu_wdt_ping_work);
ret = watchdog_register_device(retu_wdt);
if (ret < 0)
return ret;
if (nowayout)
retu_wdt_ping(retu_wdt);
else
retu_wdt_ping_enable(wdev);
platform_set_drvdata(pdev, retu_wdt);
return 0;
}
static int retu_wdt_remove(struct platform_device *pdev)
{
struct watchdog_device *wdog = platform_get_drvdata(pdev);
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
watchdog_unregister_device(wdog);
cancel_delayed_work_sync(&wdev->ping_work);
return 0;
}
static struct platform_driver retu_wdt_driver = {
.probe = retu_wdt_probe,
.remove = retu_wdt_remove,
.driver = {
.name = "retu-wdt",
},
};
module_platform_driver(retu_wdt_driver);
MODULE_ALIAS("platform:retu-wdt");
MODULE_DESCRIPTION("Retu watchdog");
MODULE_AUTHOR("Amit Kucheria");
MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
MODULE_LICENSE("GPL");