On 19/10/2017 at 10:55:49 +0800, Sean Wang wrote: > Hi, both > > On Wed, 2017-10-18 at 14:57 +0200, Alexandre Belloni wrote: > > On 18/10/2017 at 19:12:06 +0800, Yingjoe Chen wrote: > > > On Tue, 2017-10-17 at 17:40 +0800, sean.wang@xxxxxxxxxxxx wrote: > > > > From: Sean Wang <sean.wang@xxxxxxxxxxxx> > > > > > > > > This patch introduces the driver for the RTC on MT7622 SoC. > > > > > > > > Signed-off-by: Sean Wang <sean.wang@xxxxxxxxxxxx> > > > > --- > > > > drivers/rtc/Kconfig | 10 ++ > > > > drivers/rtc/Makefile | 1 + > > > > drivers/rtc/rtc-mt7622.c | 418 +++++++++++++++++++++++++++++++++++++++++++++++ > > > > 3 files changed, 429 insertions(+) > > > > create mode 100644 drivers/rtc/rtc-mt7622.c > > > > > > > > diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig > > > > index e0e58f3..4226295 100644 > > > > --- a/drivers/rtc/Kconfig > > > > +++ b/drivers/rtc/Kconfig > > > > @@ -1705,6 +1705,16 @@ config RTC_DRV_MOXART > > > > This driver can also be built as a module. If so, the module > > > > will be called rtc-moxart > > > > > > > > +config RTC_DRV_MEDIATEK > > > > > > How about changing this to RTC_DRV_MT7622 or RTC_DRV_MEDIATEK_SOC? > > > It is confusing to have both RTC_DRV_MEDIATEK & RTC_DRV_MT6397 here. > > > > > > > Yes, this has to be RTC_DRV_MT7622. It doesn't matter if it support > > future SoCs named differently, it will be less confusing than using > > anything with only mediatek in it. > > > > Agreed on. RTC_DRV_MT7622 will be applied instead to align the usage on > MT6397 and to get rid of such kind of confusion. > > > > > > + return -EINVAL; > > > > + > > > > + /* Keep yr_base used to calculate the calculate year when userspace > > > > + * queries and extend the maximum year the RTC can count. > > > > + */ > > > > + hw->yr_base[MTK_TC] = tm->tm_year - MTK_RTC_TM_YR_L - > > > > + (tm->tm_year % MTK_RTC_HW_YR_LIMIT); > > > > > > > > > I'm not sure this worth it. > > > If maximum year it can hold is 99, I'd bet it won't support leap year > > > correctly after 2100. This make the RTC useless after that. > > > > > > Also, yr_base is lost after power cycle, so you can't get correct year > > > back anyway. > > > > > > > I agree, the best you can do here is to only support 2000 to 2099. > > > > O.K. I will remove those yr_base extension and only consider only > support from 2000 to 2099 because of no much gain we can get from > yr_base. > > The only gain is yr_base I thought just allows people have the > opportunity to set up rtc after 2100. However, it appears to not much > practical to foresee these things after 2100 and rtc must be setup again > when either year overflowing or power cycle happens after 2100 as Joe.C > mentioned. > > In addition, I also found the rtc hardware would take year == 0 as not > leap year that works for 2100, 2200, 2300, but not for 2000, 2400, > 2800,... and thus 2000 is also needed to be excluded in both set_time > and set_alarm if only 2000 to 2099 is supported. > So you can make it work from 2001 to 2100 but I'm not sure it is worth it. -- Alexandre Belloni, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
