Commit 6831c6ed authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

PM: Drop pm_flags that is not necessary 



The variable pm_flags is used to prevent APM from being enabled
along with ACPI, which would lead to problems.  However, acpi_init()
is always called before apm_init() and after acpi_init() has
returned, it is known whether or not ACPI will be used.  Namely, if
acpi_disabled is not set after acpi_init() has returned, this means
that ACPI is enabled.  Thus, it is sufficient to check acpi_disabled
in apm_init() to prevent APM from being enabled in parallel with
ACPI.

Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Acked-by: default avatarLen Brown <len.brown@intel.com>
parent e8665002

arch/x86/kernel/apm_32.c

+2 −3
Original line number Diff line number Diff line
@@ -227,6 +227,7 @@ 
#include <linux/suspend.h>

#include <linux/kthread.h>

#include <linux/jiffies.h>

#include <linux/acpi.h>



#include <asm/system.h>

#include <asm/uaccess.h>
@@ -2331,12 +2332,11 @@ static int __init apm_init(void) 
		apm_info.disabled = 1;

		return -ENODEV;

	}

	if (pm_flags & PM_ACPI) {

	if (!acpi_disabled) {

		printk(KERN_NOTICE "apm: overridden by ACPI.\n");

		apm_info.disabled = 1;

		return -ENODEV;

	}

	pm_flags |= PM_APM;



	/*

	 * Set up the long jump entry point to the APM BIOS, which is called
@@ -2428,7 +2428,6 @@ static void __exit apm_exit(void) 
		kthread_stop(kapmd_task);

		kapmd_task = NULL;

	}

	pm_flags &= ~PM_APM;

}



module_init(apm_init);

drivers/acpi/bus.c

+5 −17
Original line number Diff line number Diff line
@@ -1007,8 +1007,7 @@ struct kobject *acpi_kobj; 


static int __init acpi_init(void)

{

	int result = 0;



	int result;



	if (acpi_disabled) {

		printk(KERN_INFO PREFIX "Interpreter disabled.\n");
@@ -1023,29 +1022,18 @@ static int __init acpi_init(void) 


	init_acpi_device_notify();

	result = acpi_bus_init();



	if (!result) {

		pci_mmcfg_late_init();

		if (pm_apm_enabled()) {

			printk(KERN_INFO PREFIX

			       "APM is already active, exiting\n");

	if (result) {

		disable_acpi();

			result = -ENODEV;

		} else {

			pm_set_acpi_flag();

		}

	} else

		disable_acpi();



	if (acpi_disabled)

		return result;

	}



	pci_mmcfg_late_init();

	acpi_scan_init();

	acpi_ec_init();

	acpi_debugfs_init();

	acpi_sleep_proc_init();

	acpi_wakeup_device_init();

	return result;

	return 0;

}



subsys_initcall(acpi_init);

include/linux/pm.h

+0 −9
Original line number Diff line number Diff line
@@ -565,15 +565,6 @@ enum dpm_order { 
	DPM_ORDER_DEV_LAST,

};



/*

 * Global Power Management flags

 * Used to keep APM and ACPI from both being active

 */

extern unsigned int	pm_flags;



#define PM_APM	1

#define PM_ACPI	2



extern int pm_generic_suspend(struct device *dev);

extern int pm_generic_resume(struct device *dev);

extern int pm_generic_freeze(struct device *dev);

include/linux/suspend.h

+0 −6
Original line number Diff line number Diff line
@@ -272,9 +272,6 @@ extern int unregister_pm_notifier(struct notifier_block *nb); 
	register_pm_notifier(&fn##_nb);			\

}



extern bool pm_apm_enabled(void);

extern void pm_set_acpi_flag(void);



/* drivers/base/power/wakeup.c */

extern bool events_check_enabled;
@@ -295,9 +292,6 @@ static inline int unregister_pm_notifier(struct notifier_block *nb) 


#define pm_notifier(fn, pri)	do { (void)(fn); } while (0)



static inline bool pm_apm_enabled(void) { return false; }

static inline void pm_set_acpi_flag(void) {}



static inline bool pm_wakeup_pending(void) { return false; }

#endif /* !CONFIG_PM_SLEEP */

kernel/power/main.c

+0 −13
Original line number Diff line number Diff line
@@ -19,19 +19,6 @@ DEFINE_MUTEX(pm_mutex); 


#ifdef CONFIG_PM_SLEEP



unsigned int pm_flags;

EXPORT_SYMBOL(pm_flags);



bool pm_apm_enabled(void)

{

	return !!(pm_flags & PM_APM);

}



void pm_set_acpi_flag(void)

{

	pm_flags |= PM_ACPI;

}



/* Routines for PM-transition notifications */



static BLOCKING_NOTIFIER_HEAD(pm_chain_head);

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