mirror of
				git://git.openwrt.org/openwrt/openwrt.git
				synced 2025-11-03 14:34:27 -05:00 
			
		
		
		
	Tested on bcm2710 (Raspberry Pi 3B). Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
		
			
				
	
	
		
			57 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
			
		
		
	
	
			57 lines
		
	
	
		
			1.6 KiB
		
	
	
	
		
			Diff
		
	
	
	
	
	
From c5bb7a9c84494071bbed123af04556f6bc76c56f Mon Sep 17 00:00:00 2001
 | 
						|
From: Phil Elwell <phil@raspberrypi.org>
 | 
						|
Date: Mon, 29 Oct 2018 14:45:45 +0000
 | 
						|
Subject: [PATCH] Revert "rtc: pcf8523: properly handle oscillator stop
 | 
						|
 bit"
 | 
						|
 | 
						|
This reverts commit ede44c908d44b166a5b6bd7caacd105c2ff5a70f.
 | 
						|
 | 
						|
See: https://github.com/raspberrypi/firmware/issues/1065
 | 
						|
 | 
						|
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
 | 
						|
---
 | 
						|
 drivers/rtc/rtc-pcf8523.c | 25 ++++++++++++++++++++++---
 | 
						|
 1 file changed, 22 insertions(+), 3 deletions(-)
 | 
						|
 | 
						|
--- a/drivers/rtc/rtc-pcf8523.c
 | 
						|
+++ b/drivers/rtc/rtc-pcf8523.c
 | 
						|
@@ -209,8 +209,28 @@ static int pcf8523_rtc_read_time(struct
 | 
						|
 	if (err < 0)
 | 
						|
 		return err;
 | 
						|
 
 | 
						|
-	if (regs[0] & REG_SECONDS_OS)
 | 
						|
-		return -EINVAL;
 | 
						|
+	if (regs[0] & REG_SECONDS_OS) {
 | 
						|
+		/*
 | 
						|
+		 * If the oscillator was stopped, try to clear the flag. Upon
 | 
						|
+		 * power-up the flag is always set, but if we cannot clear it
 | 
						|
+		 * the oscillator isn't running properly for some reason. The
 | 
						|
+		 * sensible thing therefore is to return an error, signalling
 | 
						|
+		 * that the clock cannot be assumed to be correct.
 | 
						|
+		 */
 | 
						|
+
 | 
						|
+		regs[0] &= ~REG_SECONDS_OS;
 | 
						|
+
 | 
						|
+		err = pcf8523_write(client, REG_SECONDS, regs[0]);
 | 
						|
+		if (err < 0)
 | 
						|
+			return err;
 | 
						|
+
 | 
						|
+		err = pcf8523_read(client, REG_SECONDS, ®s[0]);
 | 
						|
+		if (err < 0)
 | 
						|
+			return err;
 | 
						|
+
 | 
						|
+		if (regs[0] & REG_SECONDS_OS)
 | 
						|
+			return -EAGAIN;
 | 
						|
+	}
 | 
						|
 
 | 
						|
 	tm->tm_sec = bcd2bin(regs[0] & 0x7f);
 | 
						|
 	tm->tm_min = bcd2bin(regs[1] & 0x7f);
 | 
						|
@@ -246,7 +266,6 @@ static int pcf8523_rtc_set_time(struct d
 | 
						|
 		return err;
 | 
						|
 
 | 
						|
 	regs[0] = REG_SECONDS;
 | 
						|
-	/* This will purposely overwrite REG_SECONDS_OS */
 | 
						|
 	regs[1] = bin2bcd(tm->tm_sec);
 | 
						|
 	regs[2] = bin2bcd(tm->tm_min);
 | 
						|
 	regs[3] = bin2bcd(tm->tm_hour);
 |