Re: [U-Boot] [PATCH v2 06/11] rtc: Improve rtc_get() on s3c24x0_rtc

Dear José Miguel Gonçalves,

A better approach to avoid reading the RTC during updates, as sugested in the S3C2416 User's Manual.

Signed-off-by: José Miguel Gonçalves jose.goncalves@inov.pt

Changes for v2:

• New patch

---

drivers/rtc/s3c24x0_rtc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/rtc/s3c24x0_rtc.c b/drivers/rtc/s3c24x0_rtc.c index c16ff2e..7d04b74 100644 --- a/drivers/rtc/s3c24x0_rtc.c +++ b/drivers/rtc/s3c24x0_rtc.c @@ -65,20 +65,26 @@ int rtc_get(struct rtc_time *tmp) uchar sec, min, hour, mday, wday, mon, year; __maybe_unused uchar a_sec, a_min, a_hour, a_date, a_mon, a_year, a_armed;

• int have_retried = 0;

  /* enable access to RTC registers */ SetRTC_Access(RTC_ENABLE);

  /* read RTC registers */ do {

• sec  = readb(&rtc->bcdsec);
  

  min = readb(&rtc->bcdmin); hour = readb(&rtc->bcdhour); mday = readb(&rtc->bcddate); wday = readb(&rtc->bcdday); mon = readb(&rtc->bcdmon); year = readb(&rtc->bcdyear);
• } while (sec != readb(&rtc->bcdsec));

• sec  = readb(&rtc->bcdsec);
  

• /*
  

•  * The only way to work out whether the RTC was mid-update
  

•  * when we read it is to check the seconds counter.
  

•  * If it's zero, then we re-try the entire read.
  

•  */
  

• } while ((sec == 0) && !(have_retried++));

You don't need that parens around (have_retried++)

/* read ALARM registers */ a_sec = readb(&rtc->almsec);

Best regards, Marek Vasut