On 21.08.2015 18:43, Joonyoung Shim wrote: > According to datasheet, the S2MPS13X and S2MPS14X should update write > buffer via setting WUDR bit to high after ctrl register is written. > > If not, ALARM interrupt of rtc-s5m doesn't happen first time when i use > tools/testing/selftests/timers/rtctest.c test program and hour format is > used to 12 hour mode in Odroid-XU3 board. > > One more issue is the RTC doesn't keep time on Odroid-XU3 board when i > turn on board after power off even if RTC battery is connected. It can > be solved as setting WUDR & RUDR bits to high at the same time after > RTC_CTRL register is written. It's same with condition of only writing > ALARM registers, so this is for only S2MPS14 and we should set WUDR & > A_UDR bits to high on S2MPS13. > > I can't find any reasonable description about this like fix from > datasheet, but can find similar codes from rtc driver source of > hardkernel kernel and vender kernel.
s/vender/vendor/ > > Signed-off-by: Joonyoung Shim <[email protected]> > Cc: <[email protected]> # v3.16 > --- > Changelog for v2: > - update commit description and code to fix time keeping problem > - update the stable tag with the kernel version > > drivers/rtc/rtc-s5m.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/rtc/rtc-s5m.c b/drivers/rtc/rtc-s5m.c > index 8c70d78..646bf45 100644 > --- a/drivers/rtc/rtc-s5m.c > +++ b/drivers/rtc/rtc-s5m.c > @@ -635,6 +635,16 @@ static int s5m8767_rtc_init_reg(struct s5m_rtc_info > *info) > case S2MPS13X: > data[0] = (0 << BCD_EN_SHIFT) | (1 << MODEL24_SHIFT); > ret = regmap_write(info->regmap, info->regs->ctrl, data[0]); > + if (ret < 0) > + break; > + > + /* > + * Should set WUDR & (RUDR or AUDR) bits to high after writing > + * RTC_CTRL register like writing Alarm registers. We can't find > + * the description from datasheet but vender code does that s/vender/vendor/ > + * really. > + */ > + ret = s5m8767_rtc_set_alarm_reg(info); > break; > > default: > Reviewed-by: Krzysztof Kozlowski <[email protected]> Tested on S2MPS14 and S2MPS11: Tested-by: Krzysztof Kozlowski <[email protected]> Best regards, Krzysztof -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
