Re: [PATCH v4 06/15] rtc: rzn1: Fix alarm range check truncation on 32-bit systems

Hi Wolfram,

On Wed, Aug 19, 2026 at 2:05 PM Wolfram Sang
<[email protected]> wrote:
>
>
> > [Severity: High]
> > This is a pre-existing issue, but can this sequence of register writes
> > trigger a spurious interrupt?
>
> I think this is true.
>
Agreed, I will add a patch to disable the interrupts before
programming the ALx registers.

diff --git a/drivers/rtc/rtc-rzn1.c b/drivers/rtc/rtc-rzn1.c
index 44e8db466cb7..09631a3a5134 100644
--- a/drivers/rtc/rtc-rzn1.c
+++ b/drivers/rtc/rtc-rzn1.c
@@ -280,6 +280,11 @@ static int rzn1_rtc_set_alarm(struct device *dev,
struct rtc_wkalrm *alrm)
        if (alarm > farest)
                return -ERANGE;

+       /* Disable alarm interrupts before reprogramming the alarm. */
+       ret = rzn1_rtc_alarm_irq_enable(dev, 0);
+       if (ret)
+               return ret;
+
        writel(bin2bcd(tm->tm_min), rtc->base + RZN1_RTC_ALM);
        writel(bin2bcd(tm->tm_hour), rtc->base + RZN1_RTC_ALH);
        writel(BIT(tm->tm_wday), rtc->base + RZN1_RTC_ALW);

Cheers,
Prabhakar