[PATCHv1 0/3] Enable RTC on Odroid N2

[Neil Armstrong]

Hi,

On 16/07/2020 10:14, Anand Moon wrote:
> Hi Neil,
> 
> Thanks for your review comments.
> 
> On Thu, 16 Jul 2020 at 12:35, Neil Armstrong <narmstrong at baylibre.com> wrote:
>>
>> Hi Anand,
>>
>> Only the vrtc is able to wakeup the device from suspend,
>> the external RTC is not capable.
>>
>> Neil
> 
> Now I have two RTC driver registered
> 
> $ dmesg | grep rtc
> [    4.737315] rtc-pcf8563 0-0051: registered as rtc0
> [    4.738763] rtc-pcf8563 0-0051: setting system clock to
> 2020-07-16T08:00:46 UTC (1594886446)
> [    4.790206] meson-vrtc ff8000a8.rtc: registered as rtc1
> 
> And there are two nodes
> # ls /dev/rtc*
> /dev/rtc  /dev/rtc0  /dev/rtc1
> 
> So it seames an issue that /dev/rtc0 is not able to handle wakeup events.
> How can we resolve this issue?
> 
> # time rtcwake -s 30 -m mem
> rtcwake: /dev/rtc0 not enabled for wakeup events

rtcwake -d /dev/rtc1 -s 30 -m mem

As Christian reported off-list, it may be necessary to keep the vrtc as rtc0,
so you should add aliases in the odroid-n2 DT to have vrtc as rtc0 and the on-board
rtc as rtc1, but it may break the hwclock tools, so the reverse may be better
but you'll need to specify rtc1 to rtcwake.

Neil

> 
> real    0m0.002s
> user    0m0.001s
> sys     0m0.002s
> 
> -Anand
>