cregit-Linux how code gets into the kernel

Release 4.10 drivers/watchdog/ep93xx_wdt.c

Directory: drivers/watchdog
/*
 * 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.
 *
 * TODO:
 *
 *      - Test last reset from watchdog status
 *      - Add a few missing ioctls
 */

#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/watchdog.h>
#include <linux/timer.h>
#include <linux/io.h>


#define WDT_VERSION	"0.4"

/* 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 = WDT_TIMEOUT;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
	"Watchdog timeout in seconds. (1<=timeout<=3600, default="
				__MODULE_STRING(WDT_TIMEOUT) ")");


static void __iomem *mmio_base;

static struct timer_list timer;

static unsigned long next_heartbeat;


#define EP93XX_WATCHDOG		0x00

#define EP93XX_WDSTATUS		0x04

/* reset the wdt every ~200ms - the heartbeat of the device is 0.250 seconds*/

#define WDT_INTERVAL (HZ/5)


static void ep93xx_wdt_timer_ping(unsigned long data) { if (time_before(jiffies, next_heartbeat)) writel(0x5555, mmio_base + EP93XX_WATCHDOG); /* Re-set the timer interval */ mod_timer(&timer, jiffies + WDT_INTERVAL); }

Contributors

PersonTokensPropCommitsCommitProp
h hartley sweetenh hartley sweeten2256.41%266.67%
alessandro zummoalessandro zummo1743.59%133.33%
Total39100.00%3100.00%


static int ep93xx_wdt_start(struct watchdog_device *wdd) { next_heartbeat = jiffies + (timeout * HZ); writel(0xaaaa, mmio_base + EP93XX_WATCHDOG); mod_timer(&timer, jiffies + WDT_INTERVAL); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
alessandro zummoalessandro zummo2660.47%150.00%
h hartley sweetenh hartley sweeten1739.53%150.00%
Total43100.00%2100.00%


static int ep93xx_wdt_stop(struct watchdog_device *wdd) { del_timer_sync(&timer); writel(0xaa55, mmio_base + EP93XX_WATCHDOG); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
h hartley sweetenh hartley sweeten1758.62%150.00%
alessandro zummoalessandro zummo1241.38%150.00%
Total29100.00%2100.00%


static int ep93xx_wdt_keepalive(struct watchdog_device *wdd) { /* user land ping */ next_heartbeat = jiffies + (timeout * HZ); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
alessandro zummoalessandro zummo1976.00%150.00%
h hartley sweetenh hartley sweeten624.00%150.00%
Total25100.00%2100.00%

static const struct watchdog_info ep93xx_wdt_ident = { .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, .identity = "EP93xx Watchdog", }; static struct watchdog_ops ep93xx_wdt_ops = { .owner = THIS_MODULE, .start = ep93xx_wdt_start, .stop = ep93xx_wdt_stop, .ping = ep93xx_wdt_keepalive, }; static struct watchdog_device ep93xx_wdt_wdd = { .info = &ep93xx_wdt_ident, .ops = &ep93xx_wdt_ops, };
static int ep93xx_wdt_probe(struct platform_device *pdev) { struct resource *res; unsigned long val; int err; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); mmio_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(mmio_base)) return PTR_ERR(mmio_base); if (timeout < 1 || timeout > 3600) { timeout = WDT_TIMEOUT; dev_warn(&pdev->dev, "timeout value must be 1<=x<=3600, using %d\n", timeout); } val = readl(mmio_base + EP93XX_WATCHDOG); ep93xx_wdt_wdd.bootstatus = (val & 0x01) ? WDIOF_CARDRESET : 0; ep93xx_wdt_wdd.timeout = timeout; ep93xx_wdt_wdd.parent = &pdev->dev; watchdog_set_nowayout(&ep93xx_wdt_wdd, nowayout); setup_timer(&timer, ep93xx_wdt_timer_ping, 1); err = watchdog_register_device(&ep93xx_wdt_wdd); if (err) return err; dev_info(&pdev->dev, "EP93XX watchdog, driver version " WDT_VERSION "%s\n", (val & 0x08) ? " (nCS1 disable detected)" : ""); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
h hartley sweetenh hartley sweeten8848.09%225.00%
wim van sebroeckwim van sebroeck3318.03%112.50%
alessandro zummoalessandro zummo3217.49%112.50%
pratyush anandpratyush anand94.92%112.50%
jingoo hanjingoo han84.37%112.50%
joe perchesjoe perches73.83%112.50%
mika westerbergmika westerberg63.28%112.50%
Total183100.00%8100.00%


static int ep93xx_wdt_remove(struct platform_device *pdev) { watchdog_unregister_device(&ep93xx_wdt_wdd); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
h hartley sweetenh hartley sweeten1155.00%266.67%
alessandro zummoalessandro zummo945.00%133.33%
Total20100.00%3100.00%

static struct platform_driver ep93xx_wdt_driver = { .driver = { .name = "ep93xx-wdt", }, .probe = ep93xx_wdt_probe, .remove = ep93xx_wdt_remove, }; 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"); MODULE_VERSION(WDT_VERSION);

Overall Contributors

PersonTokensPropCommitsCommitProp
h hartley sweetenh hartley sweeten26045.38%214.29%
alessandro zummoalessandro zummo23140.31%17.14%
wim van sebroeckwim van sebroeck386.63%428.57%
jingoo hanjingoo han183.14%214.29%
pratyush anandpratyush anand91.57%17.14%
joe perchesjoe perches71.22%17.14%
mika westerbergmika westerberg61.05%17.14%
arnd bergmannarnd bergmann30.52%17.14%
ryan mallonryan mallon10.17%17.14%
Total573100.00%14100.00%
Directory: drivers/watchdog
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.