linux-imx

/*

 *  Copyright (C) 2010, Paul Cercueil <paul@crapouillou.net>

 *  JZ4740 Watchdog driver

 *

 *  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.

 *

 *  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.,

 *  675 Mass Ave, Cambridge, MA 02139, USA.

 *

 */

​

#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/types.h>

#include <linux/kernel.h>

#include <linux/watchdog.h>

#include <linux/platform_device.h>

#include <linux/io.h>

#include <linux/device.h>

#include <linux/clk.h>

#include <linux/slab.h>

#include <linux/err.h>

#include <linux/of.h>

​

#include <asm/mach-jz4740/timer.h>

​

#define JZ_REG_WDT_TIMER_DATA     0x0

#define JZ_REG_WDT_COUNTER_ENABLE 0x4

#define JZ_REG_WDT_TIMER_COUNTER  0x8

#define JZ_REG_WDT_TIMER_CONTROL  0xC

​

#define JZ_WDT_CLOCK_PCLK 0x1

#define JZ_WDT_CLOCK_RTC  0x2

#define JZ_WDT_CLOCK_EXT  0x4

​

#define JZ_WDT_CLOCK_DIV_SHIFT   3

​

#define JZ_WDT_CLOCK_DIV_1    (0 << JZ_WDT_CLOCK_DIV_SHIFT)

#define JZ_WDT_CLOCK_DIV_4    (1 << JZ_WDT_CLOCK_DIV_SHIFT)

#define JZ_WDT_CLOCK_DIV_16   (2 << JZ_WDT_CLOCK_DIV_SHIFT)

#define JZ_WDT_CLOCK_DIV_64   (3 << JZ_WDT_CLOCK_DIV_SHIFT)

#define JZ_WDT_CLOCK_DIV_256  (4 << JZ_WDT_CLOCK_DIV_SHIFT)

#define JZ_WDT_CLOCK_DIV_1024 (5 << JZ_WDT_CLOCK_DIV_SHIFT)

​

#define DEFAULT_HEARTBEAT 5

#define MAX_HEARTBEAT     2048

​

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 unsigned int heartbeat = DEFAULT_HEARTBEAT;

module_param(heartbeat, uint, 0);

MODULE_PARM_DESC(heartbeat,

        "Watchdog heartbeat period in seconds from 1 to "

        __MODULE_STRING(MAX_HEARTBEAT) ", default "

        __MODULE_STRING(DEFAULT_HEARTBEAT));