linux-imx

/* cpwd.c - driver implementation for hardware watchdog

 * timers found on Sun Microsystems CP1400 and CP1500 boards.

 *

 * This device supports both the generic Linux watchdog

 * interface and Solaris-compatible ioctls as best it is

 * able.

 *

 * NOTE:    CP1400 systems appear to have a defective intr_mask

 *          register on the PLD, preventing the disabling of

 *          timer interrupts.  We use a timer to periodically

 *          reset 'stopped' watchdogs on affected platforms.

 *

 * Copyright (c) 2000 Eric Brower (ebrower@usa.net)

 * Copyright (C) 2008 David S. Miller <davem@davemloft.net>

 */

​

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

​

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/fs.h>

#include <linux/errno.h>

#include <linux/major.h>

#include <linux/miscdevice.h>

#include <linux/interrupt.h>

#include <linux/ioport.h>

#include <linux/timer.h>

#include <linux/slab.h>

#include <linux/mutex.h>

#include <linux/io.h>

#include <linux/of.h>

#include <linux/of_device.h>

#include <linux/uaccess.h>

​

#include <asm/irq.h>

#include <asm/watchdog.h>

​

#define DRIVER_NAME "cpwd"

​

#define WD_OBPNAME  "watchdog"

#define WD_BADMODEL "SUNW,501-5336"

#define WD_BTIMEOUT (jiffies + (HZ * 1000))

#define WD_BLIMIT   0xFFFF

​

#define WD0_MINOR   212

#define WD1_MINOR   213

#define WD2_MINOR   214

​

/* Internal driver definitions.  */

#define WD0_ID          0

#define WD1_ID          1

#define WD2_ID          2

#define WD_NUMDEVS      3

​

#define WD_INTR_OFF     0

#define WD_INTR_ON      1

​

#define WD_STAT_INIT    0x01    /* Watchdog timer is initialized    */

#define WD_STAT_BSTOP   0x02    /* Watchdog timer is brokenstopped  */

#define WD_STAT_SVCD    0x04    /* Watchdog interrupt occurred      */

​

/* Register value definitions

 */

#define WD0_INTR_MASK   0x01    /* Watchdog device interrupt masks  */

#define WD1_INTR_MASK   0x02

#define WD2_INTR_MASK   0x04

​

#define WD_S_RUNNING    0x01    /* Watchdog device status running   */

#define WD_S_EXPIRED    0x02    /* Watchdog device status expired   */

​

struct cpwd {

    void __iomem    *regs;

    spinlock_t  lock;

​

    unsigned int    irq;

​

    unsigned long   timeout;

    bool        enabled;

    bool        reboot;

    bool        broken;

    bool        initialized;

​

    struct {

        struct miscdevice   misc;

        void __iomem        *regs;

        u8          intr_mask;

        u8          runstatus;

        u16         timeout;

    } devs[WD_NUMDEVS];

};

​

static DEFINE_MUTEX(cpwd_mutex);