From 5af9f1fa576874b24627d4c05e3a84672204c200 Mon Sep 17 00:00:00 2001 From: Liu Dalin Date: Fri, 9 May 2025 16:44:16 +0800 Subject: [PATCH] rtc: loongson: Add missing alarm notifications for ACPI RTC events When an application sets and enables an alarm on Loongson RTC devices, the alarm notification fails to propagate to userspace because the ACPI event handler omits calling rtc_update_irq(). As a result, processes waiting via select() or poll() on RTC device files fail to receive alarm notifications. The ACPI interrupt is also triggered multiple times. In loongson_rtc_handler, we need to clear TOY_MATCH0_REG to resolve this issue. Fixes: 09471d8f5b39 ("rtc: loongson: clear TOY_MATCH0_REG in loongson_rtc_isr()") Fixes: 1b733a9ebc3d ("rtc: Add rtc driver for the Loongson family chips") Signed-off-by: Liu Dalin Reviewed-by: Binbin Zhou Link: https://lore.kernel.org/r/20250509084416.7979-1-liudalin@kylinsec.com.cn Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-loongson.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/rtc/rtc-loongson.c b/drivers/rtc/rtc-loongson.c index 97e5625c064ce..2ca7ffd5d7a92 100644 --- a/drivers/rtc/rtc-loongson.c +++ b/drivers/rtc/rtc-loongson.c @@ -129,6 +129,14 @@ static u32 loongson_rtc_handler(void *id) { struct loongson_rtc_priv *priv = (struct loongson_rtc_priv *)id; + rtc_update_irq(priv->rtcdev, 1, RTC_AF | RTC_IRQF); + + /* + * The TOY_MATCH0_REG should be cleared 0 here, + * otherwise the interrupt cannot be cleared. + */ + regmap_write(priv->regmap, TOY_MATCH0_REG, 0); + spin_lock(&priv->lock); /* Disable RTC alarm wakeup and interrupt */ writel(readl(priv->pm_base + PM1_EN_REG) & ~RTC_EN, -- 2.47.2