On 9/24/24 12:08, Macpaul Lin wrote:
On 9/23/24 18:00, AngeloGioacchino Del Regno wrote:
Add the RTC hardware range parameters to enable the possibility
of using the `start-year` devicetree property which, if present,
will set the start_secs parameter by overriding the defaults
that this driver is setting;
To keep compatibility with (hence have the same date/time reading
as) the old behavior, set:
- range_min to 1900-01-01 00:00:00
- range_max to 2027-12-31 23:59:59 (HW year max range is 0-127)
- start_secs defaulting to 1968-01-02 00:00:00
Please note that the oddness of starting from January 2nd is not
a hardware quirk and it's done only to get the same date/time
reading as an RTC which time was set before this commit.
Also remove the RTC_MIN_YEAR_OFFSET addition and subtraction in
callbacks set_time() and read_time() respectively, as now this
is already done by the API.
Signed-off-by: AngeloGioacchino Del Regno
<angelogioacchino.delregno@xxxxxxxxxxxxx>
---
drivers/rtc/rtc-mt6397.c | 13 ++++---------
1 file changed, 4 insertions(+), 9 deletions(-)
[snip]
Thanks for helping add new patch fix for RTC.
@@ -302,6 +293,10 @@ static int mtk_rtc_probe(struct platform_device
*pdev)
device_init_wakeup(&pdev->dev, 1);
rtc->rtc_dev->ops = &mtk_rtc_ops;
+ rtc->rtc_dev->range_min = RTC_TIMESTAMP_BEGIN_1900;
+ rtc->rtc_dev->range_max = mktime64(2027, 12, 31, 23, 59, 59);
+ rtc->rtc_dev->start_secs = mktime64(1968, 1, 2, 0, 0, 0);
+ rtc->rtc_dev->set_start_time = true;
return devm_rtc_register_device(rtc->rtc_dev);
}
Dear @Zhanhan, Please help to leave comment if you think there is
something need to be clarify. For example, I've found some relate origin
defines
in "include/linux/mfd/mt6397/rtc.h"
#define RTC_MIN_YEAR 1968
#define RTC_BASE_YEAR 1900
#define RTC_NUM_YEAR 128
#define RTC_MIN_YEAR_OFFSET (RTC_MIN_YEAR - RTC_BASE_YEAR)
Should MediaTek remove RTC_MIN_YEAR and RTC_BASE_YEAR in next patch?
And since there may not exist any smartphone/tablet/TV using mt6397
RTC earlier than 2010? Is it possible to change
RTC_TIMESTAMP_BEGIN_1900 to RTC_TIMESTAMP_BEGIN_2000 without breaking
compatibility for these devices?
Thanks
Macpaul Lin
After discussing these change with ZhanZhan, MediaTek think use
RTC_TIMESTAMP_BEGIN_1900 and the other changes are okay.
Reviewed-by: Macpaul Lin <macpaul.lin@xxxxxxxxxxxx>
Reviewed-by: ZhanZhan Ge <zhanzhan.ge@xxxxxxxxxxxx>
Thanks!
Macpaul Lin
