acrn-kernel/drivers/watchdog/db8500_wdt.c

148 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) ST-Ericsson SA 2011-2013
*
* Author: Mathieu Poirier <mathieu.poirier@linaro.org> for ST-Ericsson
* Author: Jonas Aaberg <jonas.aberg@stericsson.com> for ST-Ericsson
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/moduleparam.h>
#include <linux/err.h>
#include <linux/uaccess.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/mfd/dbx500-prcmu.h>
#define WATCHDOG_TIMEOUT 600 /* 10 minutes */
#define WATCHDOG_MIN 0
#define WATCHDOG_MAX28 268435 /* 28 bit resolution in ms == 268435.455 s */
static unsigned int timeout = WATCHDOG_TIMEOUT;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. default="
__MODULE_STRING(WATCHDOG_TIMEOUT) ".");
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
static int db8500_wdt_start(struct watchdog_device *wdd)
{
return prcmu_enable_a9wdog(PRCMU_WDOG_ALL);
}
static int db8500_wdt_stop(struct watchdog_device *wdd)
{
return prcmu_disable_a9wdog(PRCMU_WDOG_ALL);
}
static int db8500_wdt_keepalive(struct watchdog_device *wdd)
{
return prcmu_kick_a9wdog(PRCMU_WDOG_ALL);
}
static int db8500_wdt_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
db8500_wdt_stop(wdd);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
db8500_wdt_start(wdd);
return 0;
}
static const struct watchdog_info db8500_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "DB8500 WDT",
.firmware_version = 1,
};
static const struct watchdog_ops db8500_wdt_ops = {
.owner = THIS_MODULE,
.start = db8500_wdt_start,
.stop = db8500_wdt_stop,
.ping = db8500_wdt_keepalive,
.set_timeout = db8500_wdt_set_timeout,
};
static struct watchdog_device db8500_wdt = {
.info = &db8500_wdt_info,
.ops = &db8500_wdt_ops,
.min_timeout = WATCHDOG_MIN,
.max_timeout = WATCHDOG_MAX28,
};
static int db8500_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
int ret;
timeout = 600; /* Default to 10 minutes */
db8500_wdt.parent = dev;
watchdog_set_nowayout(&db8500_wdt, nowayout);
/* disable auto off on sleep */
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);
/* set HW initial value */
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
ret = devm_watchdog_register_device(dev, &db8500_wdt);
if (ret)
return ret;
dev_info(dev, "initialized\n");
return 0;
}
static int db8500_wdt_suspend(struct platform_device *pdev,
pm_message_t state)
{
if (watchdog_active(&db8500_wdt)) {
db8500_wdt_stop(&db8500_wdt);
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, true);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
db8500_wdt_start(&db8500_wdt);
}
return 0;
}
static int db8500_wdt_resume(struct platform_device *pdev)
{
if (watchdog_active(&db8500_wdt)) {
db8500_wdt_stop(&db8500_wdt);
prcmu_config_a9wdog(PRCMU_WDOG_CPU1, false);
prcmu_load_a9wdog(PRCMU_WDOG_ALL, timeout * 1000);
db8500_wdt_start(&db8500_wdt);
}
return 0;
}
static struct platform_driver db8500_wdt_driver = {
.probe = db8500_wdt_probe,
.suspend = pm_ptr(db8500_wdt_suspend),
.resume = pm_ptr(db8500_wdt_resume),
.driver = {
.name = "db8500_wdt",
},
};
module_platform_driver(db8500_wdt_driver);
MODULE_AUTHOR("Jonas Aaberg <jonas.aberg@stericsson.com>");
MODULE_DESCRIPTION("DB8500 Watchdog Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:db8500_wdt");