raspi/linux
1
0
Fork 1
mirror of https://github.com/raspberrypi/linux.git synced 2025-12-06 01:49:46 +00:00
Code Issues Projects Releases Wiki Activity

Revert "rtc: pcf8523: properly handle oscillator stop bit"

Browse Source 
This reverts commit ede44c908d.

See: https://github.com/raspberrypi/firmware/issues/1065

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
This commit is contained in:
Phil Elwell
2018-10-29 14:45:45 +00:00
committed by popcornmix
parent 5cd8367359
commit fa22e2a500
1 changed files with 22 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

25
drivers/rtc/rtc-pcf8523.c
View File

@@ -205,8 +205,28 @@ static int pcf8523_rtc_read_time(struct device *dev, struct rtc_time *tm)
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, &regs[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);
@@ -242,7 +262,6 @@ static int pcf8523_rtc_set_time(struct device *dev, struct rtc_time *tm)
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);