[mirror_ubuntu-artful-kernel.git] / drivers / watchdog / twl4030_wdt.c

/*
 * Copyright (C) Nokia Corporation
 *
 * Written by Timo Kokkonen <timo.t.kokkonen at nokia.com>
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/i2c/twl.h>

#define TWL4030_WATCHDOG_CFG_REG_OFFS	0x3

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 twl4030_wdt_write(unsigned char val)
{
	return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val,
					TWL4030_WATCHDOG_CFG_REG_OFFS);
}

static int twl4030_wdt_start(struct watchdog_device *wdt)
{
	return twl4030_wdt_write(wdt->timeout + 1);
}

static int twl4030_wdt_stop(struct watchdog_device *wdt)
{
	return twl4030_wdt_write(0);
}

static int twl4030_wdt_set_timeout(struct watchdog_device *wdt,
				   unsigned int timeout)
{
	wdt->timeout = timeout;
	return 0;
}

static const struct watchdog_info twl4030_wdt_info = {
	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
	.identity = "TWL4030 Watchdog",
};

static const struct watchdog_ops twl4030_wdt_ops = {
	.owner		= THIS_MODULE,
	.start		= twl4030_wdt_start,
	.stop		= twl4030_wdt_stop,
	.set_timeout	= twl4030_wdt_set_timeout,
};

static int twl4030_wdt_probe(struct platform_device *pdev)
{
	int ret = 0;
	struct watchdog_device *wdt;

	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
	if (!wdt)
		return -ENOMEM;

	wdt->info		= &twl4030_wdt_info;
	wdt->ops		= &twl4030_wdt_ops;
	wdt->status		= 0;
	wdt->timeout		= 30;
	wdt->min_timeout	= 1;
	wdt->max_timeout	= 30;

	watchdog_set_nowayout(wdt, nowayout);
	platform_set_drvdata(pdev, wdt);

	twl4030_wdt_stop(wdt);

	ret = watchdog_register_device(wdt);
	if (ret)
		return ret;

	return 0;
}

static int twl4030_wdt_remove(struct platform_device *pdev)
{
	struct watchdog_device *wdt = platform_get_drvdata(pdev);

	watchdog_unregister_device(wdt);

	return 0;
}

#ifdef CONFIG_PM
static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
{
	struct watchdog_device *wdt = platform_get_drvdata(pdev);
	if (watchdog_active(wdt))
		return twl4030_wdt_stop(wdt);

	return 0;
}

static int twl4030_wdt_resume(struct platform_device *pdev)
{
	struct watchdog_device *wdt = platform_get_drvdata(pdev);
	if (watchdog_active(wdt))
		return twl4030_wdt_start(wdt);

	return 0;
}
#else
#define twl4030_wdt_suspend        NULL
#define twl4030_wdt_resume         NULL
#endif

static const struct of_device_id twl_wdt_of_match[] = {
	{ .compatible = "ti,twl4030-wdt", },
	{ },
};
MODULE_DEVICE_TABLE(of, twl_wdt_of_match);

static struct platform_driver twl4030_wdt_driver = {
	.probe		= twl4030_wdt_probe,
	.remove		= twl4030_wdt_remove,
	.suspend	= twl4030_wdt_suspend,
	.resume		= twl4030_wdt_resume,
	.driver		= {
		.owner		= THIS_MODULE,
		.name		= "twl4030_wdt",
		.of_match_table	= twl_wdt_of_match,
	},
};

module_platform_driver(twl4030_wdt_driver);

MODULE_AUTHOR("Nokia Corporation");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:twl4030_wdt");
Commit	Line	Data
80e45b1e TK	1	/*
	2	* Copyright (C) Nokia Corporation
	3	*
	4	* Written by Timo Kokkonen <timo.t.kokkonen at nokia.com>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
	20
	21	#include <linux/module.h>
	22	#include <linux/types.h>
5a0e3ad6	23	#include <linux/slab.h>
80e45b1e	24	#include <linux/kernel.h>
80e45b1e TK	25	#include <linux/watchdog.h>
80e45b1e TK	26	#include <linux/platform_device.h>
b07682b6	27	#include <linux/i2c/twl.h>
80e45b1e TK	28
	29	#define TWL4030_WATCHDOG_CFG_REG_OFFS 0x3
	30
86a1e189 WVS	31	static bool nowayout = WATCHDOG_NOWAYOUT;
86a1e189 WVS	32	module_param(nowayout, bool, 0);
80e45b1e TK	33	MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
	34	"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
	35
	36	static int twl4030_wdt_write(unsigned char val)
	37	{
2bc3f62f	38	return twl_i2c_write_u8(TWL_MODULE_PM_RECEIVER, val,
80e45b1e TK	39	TWL4030_WATCHDOG_CFG_REG_OFFS);
	40	}
	41
b2c4e4b2	42	static int twl4030_wdt_start(struct watchdog_device *wdt)
80e45b1e	43	{
b2c4e4b2	44	return twl4030_wdt_write(wdt->timeout + 1);
80e45b1e TK	45	}
80e45b1e TK	46
b2c4e4b2	47	static int twl4030_wdt_stop(struct watchdog_device *wdt)
80e45b1e TK	48	{
	49	return twl4030_wdt_write(0);
	50	}
	51
b2c4e4b2 JN	52	static int twl4030_wdt_set_timeout(struct watchdog_device *wdt,
b2c4e4b2 JN	53	unsigned int timeout)
80e45b1e	54	{
b2c4e4b2	55	wdt->timeout = timeout;
80e45b1e TK	56	return 0;
	57	}
	58
b2c4e4b2 JN	59	static const struct watchdog_info twl4030_wdt_info = {
	60	.options = WDIOF_SETTIMEOUT \| WDIOF_KEEPALIVEPING,
	61	.identity = "TWL4030 Watchdog",
	62	};
80e45b1e	63
b2c4e4b2	64	static const struct watchdog_ops twl4030_wdt_ops = {
80e45b1e	65	.owner = THIS_MODULE,
b2c4e4b2 JN	66	.start = twl4030_wdt_start,
	67	.stop = twl4030_wdt_stop,
	68	.set_timeout = twl4030_wdt_set_timeout,
80e45b1e TK	69	};
80e45b1e TK	70
2d991a16	71	static int twl4030_wdt_probe(struct platform_device *pdev)
80e45b1e TK	72	{
80e45b1e TK	73	int ret = 0;
b2c4e4b2	74	struct watchdog_device *wdt;
80e45b1e	75
b2c4e4b2	76	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
80e45b1e TK	77	if (!wdt)
	78	return -ENOMEM;
	79
b2c4e4b2 JN	80	wdt->info = &twl4030_wdt_info;
	81	wdt->ops = &twl4030_wdt_ops;
	82	wdt->status = 0;
	83	wdt->timeout = 30;
	84	wdt->min_timeout = 1;
	85	wdt->max_timeout = 30;
80e45b1e	86
b2c4e4b2	87	watchdog_set_nowayout(wdt, nowayout);
80e45b1e TK	88	platform_set_drvdata(pdev, wdt);
80e45b1e TK	89
b2c4e4b2	90	twl4030_wdt_stop(wdt);
80e45b1e	91
b2c4e4b2	92	ret = watchdog_register_device(wdt);
6638f4e5	93	if (ret)
80e45b1e	94	return ret;
b2c4e4b2	95
80e45b1e TK	96	return 0;
	97	}
	98
4b12b896	99	static int twl4030_wdt_remove(struct platform_device *pdev)
80e45b1e	100	{
b2c4e4b2	101	struct watchdog_device *wdt = platform_get_drvdata(pdev);
80e45b1e	102
b2c4e4b2	103	watchdog_unregister_device(wdt);
80e45b1e TK	104
	105	return 0;
	106	}
	107
	108	#ifdef CONFIG_PM
	109	static int twl4030_wdt_suspend(struct platform_device *pdev, pm_message_t state)
	110	{
b2c4e4b2 JN	111	struct watchdog_device *wdt = platform_get_drvdata(pdev);
	112	if (watchdog_active(wdt))
	113	return twl4030_wdt_stop(wdt);
80e45b1e TK	114
	115	return 0;
	116	}
	117
	118	static int twl4030_wdt_resume(struct platform_device *pdev)
	119	{
b2c4e4b2 JN	120	struct watchdog_device *wdt = platform_get_drvdata(pdev);
	121	if (watchdog_active(wdt))
	122	return twl4030_wdt_start(wdt);
80e45b1e TK	123
	124	return 0;
	125	}
	126	#else
	127	#define twl4030_wdt_suspend NULL
	128	#define twl4030_wdt_resume NULL
	129	#endif
	130
8899b8d9 AK	131	static const struct of_device_id twl_wdt_of_match[] = {
	132	{ .compatible = "ti,twl4030-wdt", },
	133	{ },
	134	};
	135	MODULE_DEVICE_TABLE(of, twl_wdt_of_match);
	136
80e45b1e TK	137	static struct platform_driver twl4030_wdt_driver = {
80e45b1e TK	138	.probe = twl4030_wdt_probe,
82268714	139	.remove = twl4030_wdt_remove,
80e45b1e TK	140	.suspend = twl4030_wdt_suspend,
	141	.resume = twl4030_wdt_resume,
	142	.driver = {
8899b8d9 AK	143	.owner = THIS_MODULE,
	144	.name = "twl4030_wdt",
	145	.of_match_table = twl_wdt_of_match,
80e45b1e TK	146	},
	147	};
	148
b8ec6118	149	module_platform_driver(twl4030_wdt_driver);
80e45b1e TK	150
	151	MODULE_AUTHOR("Nokia Corporation");
	152	MODULE_LICENSE("GPL");
80e45b1e TK	153	MODULE_ALIAS("platform:twl4030_wdt");
80e45b1e TK	154