Re: [PATCH 0/2] rtc: Add Qualcomm PMIC RTC-GLINK support for Glymur

[Troels Vognbjerg]

On Thu, 20 Aug 2026 at 18:38, Kamal Wadhwa
<kamal.wadhwa@xxxxxxxxxxxxxxxx> wrote:
>
> On Tue, Aug 11, 2026 at 02:10:12PM +0200, Troels Vognbjerg wrote:
> > Kamal Wadhwa <kamal.wadhwa@xxxxxxxxxxxxxxxx> wrote on Fri, 07 Aug 2026 02:26:29 +0530:
> > > On some targets like Glymur, the permission for receving the RTC
> > > alarms is routed to charger firmware running on remote subsystem.
> > >
> > > This is because Glymur boards have to  support MSFT's `TAD feature`
> > > on the windows OS devices.
> > >
> > > So rtc-pm8xxx.c driver cannot recieve RTC alarm IRQs via SPMI on
> > > Glymur. So in order to make the IRQ available on the Linux kernel,
> > > the PMIC RTC Alarm IRQ must be routed to APPS via remote subsystem.
> > >
> > > To implement this, add support for a New Qualcomm PMIC GLINK RTC
> > > client, which will request for RTC set/get calls for time/alarm IRQ
> > >  via the existing pmic_glink interface to the charger firmware.
> > >
> > > Also, add a DT property to explicily support enabling the RTC
> > > writes, keep RTC writes disabled by default to align behaviour
> > > with the existing rtc-pm8xxx.c driver.
> >
> > You mentioned this patch series applies to targets like Glymur. Does that include
> > the ASUS Zenbook A16 UX3607OA, or did ASUS do something different on this
> > laptop?
> >
> > The reason I am asking is because when I build this as a kernel module,
> > I get the following error message:
> > [    2.241461] rtc-pm8xxx c426000.spmi:pmic@0:rtc@6100: probe with driver rtc-pm8xxx failed with error -2
>
> This is a different driver error, this is for the one which works on the SPMI bus.
> While the driver that i have posted in the current series is based on pmic_glink interface, which relays the
> RTC alarm requests to charger firmware running in remote processor (which implements the Windows TAD feature)
>
> do you have this `qcom,no-alarm` prop defined?
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/glymur-crd.dtsi?h=v7.2#n565

Yes. I used the DTS for the Asus
A16.https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/glymur-asus-zenbook-a16-ux3607oa.dts#n863&pmk8850_rtc
{
qcom,uefi-rtc-info;
qcom,no-alarm;
};>
> > [    2.499556] Modules linked in: rtc_pm8xxx aes_ce_blk ghash_ce gf128mul sm4_ce_gcm sm4_ce_ccm sm4_ce sm4_ce_cipher sm4 qcom_battmgr rtc_qcom_glink(+) simple_bridge display_connector
> > [    3.277788] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> > [    4.318666] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: all time sources failed
> > [    4.319085] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: registered as rtc0
> > [    5.359404] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> > [    6.400331] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: all time sources failed
> > [    6.400496] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: hctosys: unable to read the hardware clock
> > [   25.447761] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> > [   26.488271] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: all time sources failed
> > [   27.517573] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> > [   28.560114] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: all time sources failed
> > [   29.609224] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> > [   30.638629] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: all time sources failed
> > [   31.677524] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> > [   32.720749] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: all time sources failed
> > [   33.757662] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> > [   34.808360] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: all time sources failed
> > [   35.837651] rtc_qcom_glink.qcom_pmic_rtc_glink pmic_glink.rtc-glink.0: 0x68 failed (-110), falling back
> >
> > And the error message keeps repeating every second or so.
>
> Sorry for this, i think the firmware needs to be updated for this feature, I will fix this by existing cleanly
> if the firmware doesnt support it. To avoid repeated messages.
>
> Also will check internally how you can get new firmware (if you want to use it?)
Again, I am on the Asus A16. I think I better wait for Asus to the update.

> Again sorry for the trouble.
>
> >
> > --
> > Troels Vognbjerg
>
> Regards,
> Kamal

-- 
Troels Vognbjerg