45 lines
		
	
	
	
		
			1.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			45 lines
		
	
	
	
		
			1.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * This program is free software; you can redistribute it and/or modify it | ||
|  |  * under the terms of the GNU General Public License version 2 as published by | ||
|  |  * the Free Software Foundation. | ||
|  |  * | ||
|  |  */ | ||
|  | #include <linux/rtc.h>
 | ||
|  | #include <linux/time.h>
 | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * rtc_set_ntp_time - Save NTP synchronized time to the RTC | ||
|  |  * @now: Current time of day | ||
|  |  * | ||
|  |  * Replacement for the NTP platform function update_persistent_clock | ||
|  |  * that stores time for later retrieval by rtc_hctosys. | ||
|  |  * | ||
|  |  * Returns 0 on successful RTC update, -ENODEV if a RTC update is not | ||
|  |  * possible at all, and various other -errno for specific temporary failure | ||
|  |  * cases. | ||
|  |  * | ||
|  |  * If temporary failure is indicated the caller should try again 'soon' | ||
|  |  */ | ||
|  | int rtc_set_ntp_time(struct timespec now) | ||
|  | { | ||
|  | 	struct rtc_device *rtc; | ||
|  | 	struct rtc_time tm; | ||
|  | 	int err = -ENODEV; | ||
|  | 
 | ||
|  | 	if (now.tv_nsec < (NSEC_PER_SEC >> 1)) | ||
|  | 		rtc_time_to_tm(now.tv_sec, &tm); | ||
|  | 	else | ||
|  | 		rtc_time_to_tm(now.tv_sec + 1, &tm); | ||
|  | 
 | ||
|  | 	rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE); | ||
|  | 	if (rtc) { | ||
|  | 		/* rtc_hctosys exclusively uses UTC, so we call set_time here,
 | ||
|  | 		 * not set_mmss. */ | ||
|  | 		if (rtc->ops && (rtc->ops->set_time || rtc->ops->set_mmss)) | ||
|  | 			err = rtc_set_time(rtc, &tm); | ||
|  | 		rtc_class_close(rtc); | ||
|  | 	} | ||
|  | 
 | ||
|  | 	return err; | ||
|  | } |