linux-imx

// SPDX-License-Identifier: GPL-2.0+

/*

 *  Copyright (C) 2015 Mans Rullgard <mans@mansr.com>

 *  SMP86xx/SMP87xx Watchdog driver

 */

​

#include <linux/bitops.h>

#include <linux/clk.h>

#include <linux/delay.h>

#include <linux/io.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/mod_devicetable.h>

#include <linux/platform_device.h>

#include <linux/watchdog.h>

​

#define DEFAULT_TIMEOUT 30

​

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 timeout;

module_param(timeout, int, 0);

MODULE_PARM_DESC(timeout, "Watchdog timeout");

​

/*

 * Counter counts down from programmed value.  Reset asserts when

 * the counter reaches 1.

 */

#define WD_COUNTER      0

​

#define WD_CONFIG       4

#define WD_CONFIG_XTAL_IN   BIT(0)

#define WD_CONFIG_DISABLE   BIT(31)

​

struct tangox_wdt_device {

    struct watchdog_device wdt;

    void __iomem *base;

    unsigned long clk_rate;

    struct clk *clk;

};

​

static int tangox_wdt_set_timeout(struct watchdog_device *wdt,

                  unsigned int new_timeout)

{

    wdt->timeout = new_timeout;

​

    return 0;

}

​

static int tangox_wdt_start(struct watchdog_device *wdt)

{

    struct tangox_wdt_device *dev = watchdog_get_drvdata(wdt);

    u32 ticks;

​

    ticks = 1 + wdt->timeout * dev->clk_rate;

    writel(ticks, dev->base + WD_COUNTER);

​

    return 0;