Commit 4c24e29e authored by David Fries's avatar David Fries Committed by Linus Torvalds
Browse files

rtc_sysfs_show_hctosys(): display 0 if resume failed 



Without this patch /sys/class/rtc/$CONFIG_RTC_HCTOSYS_DEVICE/hctosys
contains a 1 (meaning "This rtc was used to initialize the system
clock") even if setting the time by do_settimeofday() at bootup failed.
The RTC can also be used to set the clock on resume, if it did 1,
otherwise 0.  Previously there was no indication if the RTC was used
to set the clock in resume.

This uses only CONFIG_RTC_HCTOSYS_DEVICE for conditional compilation
instead of it and CONFIG_RTC_HCTOSYS to be more consistent.
rtc_hctosys_ret was moved to class.c so class.c no longer depends on
hctosys.c.

[sfr@canb.auug.org.au: fix build]
Signed-off-by: default avatarDavid Fries <David@Fries.net>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: default avatarStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent be8b6d51

drivers/rtc/class.c

+7 −1
Original line number Diff line number Diff line
@@ -31,8 +31,12 @@ static void rtc_device_release(struct device *dev) 
	kfree(rtc);

}



#if defined(CONFIG_PM) && defined(CONFIG_RTC_HCTOSYS_DEVICE)

#ifdef CONFIG_RTC_HCTOSYS_DEVICE

/* Result of the last RTC to system clock attempt. */

int rtc_hctosys_ret = -ENODEV;

#endif



#if defined(CONFIG_PM) && defined(CONFIG_RTC_HCTOSYS_DEVICE)

/*

 * On suspend(), measure the delta between one RTC and the

 * system's wall clock; restore it on resume().
@@ -84,6 +88,7 @@ static int rtc_resume(struct device *dev) 
	struct timespec		new_system, new_rtc;

	struct timespec		sleep_time;



	rtc_hctosys_ret = -ENODEV;

	if (strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE) != 0)

		return 0;
@@ -117,6 +122,7 @@ static int rtc_resume(struct device *dev) 


	if (sleep_time.tv_sec >= 0)

		timekeeping_inject_sleeptime(&sleep_time);

	rtc_hctosys_ret = 0;

	return 0;

}

drivers/rtc/hctosys.c

+1 −3
Original line number Diff line number Diff line
@@ -22,8 +22,6 @@ 
 * the best guess is to add 0.5s.

 */



int rtc_hctosys_ret = -ENODEV;



static int __init rtc_hctosys(void)

{

	int err = -ENODEV;
@@ -56,7 +54,7 @@ static int __init rtc_hctosys(void) 


	rtc_tm_to_time(&tm, &tv.tv_sec);



	do_settimeofday(&tv);

	err = do_settimeofday(&tv);



	dev_info(rtc->dev.parent,

		"setting system clock to "

drivers/rtc/rtc-sysfs.c

+6 −0
Original line number Diff line number Diff line
@@ -102,6 +102,12 @@ rtc_sysfs_set_max_user_freq(struct device *dev, struct device_attribute *attr, 
	return n;

}



/**

 * rtc_sysfs_show_hctosys - indicate if the given RTC set the system time

 *

 * Returns 1 if the system clock was set by this RTC at the last

 * boot or resume event.

 */

static ssize_t

rtc_sysfs_show_hctosys(struct device *dev, struct device_attribute *attr,

		char *buf)

include/linux/rtc.h

+1 −1
Original line number Diff line number Diff line
@@ -276,7 +276,7 @@ static inline bool is_leap_year(unsigned int year) 
	return (!(year % 4) && (year % 100)) || !(year % 400);

}



#ifdef CONFIG_RTC_HCTOSYS

#ifdef CONFIG_RTC_HCTOSYS_DEVICE

extern int rtc_hctosys_ret;

#else

#define rtc_hctosys_ret -ENODEV

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