[PATCH v2 1/3] arm64: dts: meson-g12b-odroid-n2: Enable RTC controller node

[Anand Moon]

Hi Martin, Jerome,

Thanks for your review comments.

On Tue, 18 Aug 2020 at 13:13, Jerome Brunet <jbrunet at baylibre.com> wrote:
>
>
> >> > >
> >> > > +&i2c3 {
> >> > > +       pinctrl-0 = <&i2c3_sda_a_pins>, <&i2c3_sck_a_pins>;
> >> > > +       pinctrl-1 = <&tdm_c_din3_a_pins>;
> >
> > Note: without setting this *pinctrl-1* configuration RTC wake up
> > feature works as expected.
>
> As pointed out by Martin, the pinctrl-1 here makes no sense for RTC on
> i2c. If the rtc is on an I2C of AO bank, the pinctrl-0 is likely to be
> wrong as well.

Ok are you suggesting *I2C_AO_S0_SCL* and *I2C_AO_S0_SDA* pins.

+&i2c_AO {
+       status = "okay";
+       pinctrl-0 = <&i2c_ao_sck_pins>, <&i2c_ao_sda_pins>;
+       pinctrl-names = "default";
+
+       rtc at 51 {
+               compatible = "nxp,pcf8563";
+               reg = <0x51>;
+               #clock-cells = <0>;
+       };
+};

But I get the following output with this configuration.

[root at archl-on2e ~]# dmesg | grep rtc
[    5.284632] rtc-pcf8563 0-0051: registered as rtc0
[    5.300148] rtc-pcf8563 0-0051: hctosys: unable to read the hardware clock

I also tried to move the my rtc nodes under i2c_AO, but I got the same result.

[root at archl-on2e ~]# dmesg | grep rtc
[    5.447423] rtc-pcf8563 0-0051: registered as rtc0
[    5.457465] rtc-pcf8563 0-0051: hctosys: unable to read the hardware clock

But as per the schematic RTC configured using GPIOA.BIT14 (SDA) and
GPIOA.BIT15 (SCL)
And with this configuration with i2c3 node RTC is getting configured correctly.

[root at archl-on2e ~]#  dmesg | grep rtc
[    5.240760] rtc-pcf8563 0-0051: registered as rtc0
[    5.243225] rtc-pcf8563 0-0051: setting system clock to
2020-08-18T10:23:04 UTC (1597746184)

Best Regards
-Anand