147 lines
3.6 KiB
C
147 lines
3.6 KiB
C
/*
|
|
* Watchdog driver for Cirrus Logic EP93xx family of devices.
|
|
*
|
|
* Copyright (c) 2004 Ray Lehtiniemi
|
|
* Copyright (c) 2006 Tower Technologies
|
|
* Based on ep93xx driver, bits from alim7101_wdt.c
|
|
*
|
|
* Authors: Ray Lehtiniemi <rayl@mail.com>,
|
|
* Alessandro Zummo <a.zummo@towertech.it>
|
|
*
|
|
* Copyright (c) 2012 H Hartley Sweeten <hsweeten@visionengravers.com>
|
|
* Convert to a platform device and use the watchdog framework API
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*
|
|
* This watchdog fires after 250msec, which is a too short interval
|
|
* for us to rely on the user space daemon alone. So we ping the
|
|
* wdt each ~200msec and eventually stop doing it if the user space
|
|
* daemon dies.
|
|
*/
|
|
|
|
#include <linux/platform_device.h>
|
|
#include <linux/module.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/io.h>
|
|
|
|
/* default timeout (secs) */
|
|
#define WDT_TIMEOUT 30
|
|
|
|
static bool nowayout = WATCHDOG_NOWAYOUT;
|
|
module_param(nowayout, bool, 0);
|
|
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started");
|
|
|
|
static unsigned int timeout;
|
|
module_param(timeout, uint, 0);
|
|
MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds.");
|
|
|
|
#define EP93XX_WATCHDOG 0x00
|
|
#define EP93XX_WDSTATUS 0x04
|
|
|
|
struct ep93xx_wdt_priv {
|
|
void __iomem *mmio;
|
|
struct watchdog_device wdd;
|
|
};
|
|
|
|
static int ep93xx_wdt_start(struct watchdog_device *wdd)
|
|
{
|
|
struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
|
|
|
writel(0xaaaa, priv->mmio + EP93XX_WATCHDOG);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ep93xx_wdt_stop(struct watchdog_device *wdd)
|
|
{
|
|
struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
|
|
|
writel(0xaa55, priv->mmio + EP93XX_WATCHDOG);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ep93xx_wdt_ping(struct watchdog_device *wdd)
|
|
{
|
|
struct ep93xx_wdt_priv *priv = watchdog_get_drvdata(wdd);
|
|
|
|
writel(0x5555, priv->mmio + EP93XX_WATCHDOG);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct watchdog_info ep93xx_wdt_ident = {
|
|
.options = WDIOF_CARDRESET |
|
|
WDIOF_SETTIMEOUT |
|
|
WDIOF_MAGICCLOSE |
|
|
WDIOF_KEEPALIVEPING,
|
|
.identity = "EP93xx Watchdog",
|
|
};
|
|
|
|
static const struct watchdog_ops ep93xx_wdt_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = ep93xx_wdt_start,
|
|
.stop = ep93xx_wdt_stop,
|
|
.ping = ep93xx_wdt_ping,
|
|
};
|
|
|
|
static int ep93xx_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct ep93xx_wdt_priv *priv;
|
|
struct watchdog_device *wdd;
|
|
unsigned long val;
|
|
int ret;
|
|
|
|
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
|
|
if (!priv)
|
|
return -ENOMEM;
|
|
|
|
priv->mmio = devm_platform_ioremap_resource(pdev, 0);
|
|
if (IS_ERR(priv->mmio))
|
|
return PTR_ERR(priv->mmio);
|
|
|
|
val = readl(priv->mmio + EP93XX_WATCHDOG);
|
|
|
|
wdd = &priv->wdd;
|
|
wdd->bootstatus = (val & 0x01) ? WDIOF_CARDRESET : 0;
|
|
wdd->info = &ep93xx_wdt_ident;
|
|
wdd->ops = &ep93xx_wdt_ops;
|
|
wdd->min_timeout = 1;
|
|
wdd->max_hw_heartbeat_ms = 200;
|
|
wdd->parent = dev;
|
|
|
|
watchdog_set_nowayout(wdd, nowayout);
|
|
|
|
wdd->timeout = WDT_TIMEOUT;
|
|
watchdog_init_timeout(wdd, timeout, dev);
|
|
|
|
watchdog_set_drvdata(wdd, priv);
|
|
|
|
ret = devm_watchdog_register_device(dev, wdd);
|
|
if (ret)
|
|
return ret;
|
|
|
|
dev_info(dev, "EP93XX watchdog driver %s\n",
|
|
(val & 0x08) ? " (nCS1 disable detected)" : "");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver ep93xx_wdt_driver = {
|
|
.driver = {
|
|
.name = "ep93xx-wdt",
|
|
},
|
|
.probe = ep93xx_wdt_probe,
|
|
};
|
|
|
|
module_platform_driver(ep93xx_wdt_driver);
|
|
|
|
MODULE_AUTHOR("Ray Lehtiniemi <rayl@mail.com>");
|
|
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
|
|
MODULE_AUTHOR("H Hartley Sweeten <hsweeten@visionengravers.com>");
|
|
MODULE_DESCRIPTION("EP93xx Watchdog");
|
|
MODULE_LICENSE("GPL");
|