[deliverable/linux.git] / drivers / watchdog / bcm47xx_wdt.c

/*
 *  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 */

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 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;
	struct bcm47xx_wdt *wdt = dev_get_platdata(&pdev->dev);

	if (!wdt)
		return -ENXIO;

	setup_timer(&wdt->soft_timer, bcm47xx_wdt_soft_timer_tick,
		    (long unsigned int)wdt);

	wdt->wdd.ops = &bcm47xx_wdt_soft_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;

	pr_info("BCM47xx Watchdog Timer enabled (%d seconds%s)\n",
		timeout, nowayout ? ", nowayout" : "");
	return 0;

err_notifier:
	unregister_reboot_notifier(&wdt->notifier);
err_timer:
	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");
Commit	Line	Data
	1	/*
	2	* Watchdog driver for Broadcom BCM47XX
	3	*
	4	* Copyright (C) 2008 Aleksandar Radovanovic <biblbroks@sezampro.rs>
	5	* Copyright (C) 2009 Matthieu CASTET <castet.matthieu@free.fr>
	6	* Copyright (C) 2012-2013 Hauke Mehrtens <hauke@hauke-m.de>
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License
	10	* as published by the Free Software Foundation; either version
	11	* 2 of the License, or (at your option) any later version.
	12	*/
	13
	14	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	15
	16	#include <linux/bcm47xx_wdt.h>
	17	#include <linux/bitops.h>
	18	#include <linux/errno.h>
	19	#include <linux/init.h>
	20	#include <linux/kernel.h>
	21	#include <linux/module.h>
	22	#include <linux/moduleparam.h>
	23	#include <linux/platform_device.h>
	24	#include <linux/reboot.h>
	25	#include <linux/types.h>
	26	#include <linux/watchdog.h>
	27	#include <linux/timer.h>
	28	#include <linux/jiffies.h>
	29
	30	#define DRV_NAME "bcm47xx_wdt"
	31
	32	#define WDT_DEFAULT_TIME 30 /* seconds */
	33	#define WDT_SOFTTIMER_MAX 255 /* seconds */
	34
	35	static int timeout = WDT_DEFAULT_TIME;
	36	static bool nowayout = WATCHDOG_NOWAYOUT;
	37
	38	module_param(timeout, int, 0);
	39	MODULE_PARM_DESC(timeout, "Watchdog time in seconds. (default="
	40	__MODULE_STRING(WDT_DEFAULT_TIME) ")");
	41
	42	module_param(nowayout, bool, 0);
	43	MODULE_PARM_DESC(nowayout,
	44	"Watchdog cannot be stopped once started (default="
	45	__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
	46
	47	static inline struct bcm47xx_wdt bcm47xx_wdt_get(struct watchdog_device wdd)
	48	{
	49	return container_of(wdd, struct bcm47xx_wdt, wdd);
	50	}
	51
	52	static void bcm47xx_wdt_soft_timer_tick(unsigned long data)
	53	{
	54	struct bcm47xx_wdt wdt = (struct bcm47xx_wdt )data;
	55	u32 next_tick = min(wdt->wdd.timeout * 1000, wdt->max_timer_ms);
	56
	57	if (!atomic_dec_and_test(&wdt->soft_ticks)) {
	58	wdt->timer_set_ms(wdt, next_tick);
	59	mod_timer(&wdt->soft_timer, jiffies + HZ);
	60	} else {
	61	pr_crit("Watchdog will fire soon!!!\n");
	62	}
	63	}
	64
	65	static int bcm47xx_wdt_soft_keepalive(struct watchdog_device *wdd)
	66	{
	67	struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
	68
	69	atomic_set(&wdt->soft_ticks, wdd->timeout);
	70
	71	return 0;
	72	}
	73
	74	static int bcm47xx_wdt_soft_start(struct watchdog_device *wdd)
	75	{
	76	struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
	77
	78	bcm47xx_wdt_soft_keepalive(wdd);
	79	bcm47xx_wdt_soft_timer_tick((unsigned long)wdt);
	80
	81	return 0;
	82	}
	83
	84	static int bcm47xx_wdt_soft_stop(struct watchdog_device *wdd)
	85	{
	86	struct bcm47xx_wdt *wdt = bcm47xx_wdt_get(wdd);
	87
	88	del_timer_sync(&wdt->soft_timer);
	89	wdt->timer_set(wdt, 0);
	90
	91	return 0;
	92	}
	93
	94	static int bcm47xx_wdt_soft_set_timeout(struct watchdog_device *wdd,
	95	unsigned int new_time)
	96	{
	97	if (new_time < 1 \|\| new_time > WDT_SOFTTIMER_MAX) {
	98	pr_warn("timeout value must be 1<=x<=%d, using %d\n",
	99	WDT_SOFTTIMER_MAX, new_time);
	100	return -EINVAL;
	101	}
	102
	103	wdd->timeout = new_time;
	104	return 0;
	105	}
	106
	107	static const struct watchdog_info bcm47xx_wdt_info = {
	108	.identity = DRV_NAME,
	109	.options = WDIOF_SETTIMEOUT \|
	110	WDIOF_KEEPALIVEPING \|
	111	WDIOF_MAGICCLOSE,
	112	};
	113
	114	static int bcm47xx_wdt_notify_sys(struct notifier_block *this,
	115	unsigned long code, void *unused)
	116	{
	117	struct bcm47xx_wdt *wdt;
	118
	119	wdt = container_of(this, struct bcm47xx_wdt, notifier);
	120	if (code == SYS_DOWN \|\| code == SYS_HALT)
	121	wdt->wdd.ops->stop(&wdt->wdd);
	122	return NOTIFY_DONE;
	123	}
	124
	125	static struct watchdog_ops bcm47xx_wdt_soft_ops = {
	126	.owner = THIS_MODULE,
	127	.start = bcm47xx_wdt_soft_start,
	128	.stop = bcm47xx_wdt_soft_stop,
	129	.ping = bcm47xx_wdt_soft_keepalive,
	130	.set_timeout = bcm47xx_wdt_soft_set_timeout,
	131	};
	132
	133	static int bcm47xx_wdt_probe(struct platform_device *pdev)
	134	{
	135	int ret;
	136	struct bcm47xx_wdt *wdt = dev_get_platdata(&pdev->dev);
	137
	138	if (!wdt)
	139	return -ENXIO;
	140
	141	setup_timer(&wdt->soft_timer, bcm47xx_wdt_soft_timer_tick,
	142	(long unsigned int)wdt);
	143
	144	wdt->wdd.ops = &bcm47xx_wdt_soft_ops;
	145	wdt->wdd.info = &bcm47xx_wdt_info;
	146	wdt->wdd.timeout = WDT_DEFAULT_TIME;
	147	ret = wdt->wdd.ops->set_timeout(&wdt->wdd, timeout);
	148	if (ret)
	149	goto err_timer;
	150	watchdog_set_nowayout(&wdt->wdd, nowayout);
	151
	152	wdt->notifier.notifier_call = &bcm47xx_wdt_notify_sys;
	153
	154	ret = register_reboot_notifier(&wdt->notifier);
	155	if (ret)
	156	goto err_timer;
	157
	158	ret = watchdog_register_device(&wdt->wdd);
	159	if (ret)
	160	goto err_notifier;
	161
	162	pr_info("BCM47xx Watchdog Timer enabled (%d seconds%s)\n",
	163	timeout, nowayout ? ", nowayout" : "");
	164	return 0;
	165
	166	err_notifier:
	167	unregister_reboot_notifier(&wdt->notifier);
	168	err_timer:
	169	del_timer_sync(&wdt->soft_timer);
	170
	171	return ret;
	172	}
	173
	174	static int bcm47xx_wdt_remove(struct platform_device *pdev)
	175	{
	176	struct bcm47xx_wdt *wdt = dev_get_platdata(&pdev->dev);
	177
	178	if (!wdt)
	179	return -ENXIO;
	180
	181	watchdog_unregister_device(&wdt->wdd);
	182	unregister_reboot_notifier(&wdt->notifier);
	183
	184	return 0;
	185	}
	186
	187	static struct platform_driver bcm47xx_wdt_driver = {
	188	.driver = {
	189	.owner = THIS_MODULE,
	190	.name = "bcm47xx-wdt",
	191	},
	192	.probe = bcm47xx_wdt_probe,
	193	.remove = bcm47xx_wdt_remove,
	194	};
	195
	196	module_platform_driver(bcm47xx_wdt_driver);
	197
	198	MODULE_AUTHOR("Aleksandar Radovanovic");
	199	MODULE_AUTHOR("Hauke Mehrtens <hauke@hauke-m.de>");
	200	MODULE_DESCRIPTION("Watchdog driver for Broadcom BCM47xx");
	201	MODULE_LICENSE("GPL");