linux/drivers/acpi/acpi_watchdog.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * ACPI watchdog table parsing support.
 *
 * Copyright (C) 2016, Intel Corporation
 * Author: Mika Westerberg <[email protected]>
 */

#define pr_fmt(fmt) …

#include <linux/acpi.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>

#include "internal.h"

#ifdef CONFIG_RTC_MC146818_LIB
#include <linux/mc146818rtc.h>

/*
 * There are several systems where the WDAT table is accessing RTC SRAM to
 * store persistent information. This does not work well with the Linux RTC
 * driver so on those systems we skip WDAT driver and prefer iTCO_wdt
 * instead.
 *
 * See also https://bugzilla.kernel.org/show_bug.cgi?id=199033.
 */
static bool acpi_watchdog_uses_rtc(const struct acpi_table_wdat *wdat)
{ … }
#else
static bool acpi_watchdog_uses_rtc(const struct acpi_table_wdat *wdat)
{
	return false;
}
#endif

static bool acpi_no_watchdog;

static const struct acpi_table_wdat *acpi_watchdog_get_wdat(void)
{ … }

/*
 * Returns true if this system should prefer ACPI based watchdog instead of
 * the native one (which are typically the same hardware).
 */
bool acpi_has_watchdog(void)
{ … }
EXPORT_SYMBOL_GPL(…);

/* ACPI watchdog can be disabled on boot command line */
static int __init disable_acpi_watchdog(char *str)
{ … }
__setup(…);

void __init acpi_watchdog_init(void)
{ … }