[PATCH 2/2] rtc: ti-k3: Mark RTC time as invalid without battery backup

[Akashdeep Kaur]

TI K3 RTC typically has no battery backup. Prevent HCTOSYS from
overwriting valid system time (established by bootloader or early
NTP sync) with invalid RTC value.

Signed-off-by: Akashdeep Kaur <a-kaur@xxxxxx>
---
 drivers/rtc/rtc-ti-k3.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/rtc/rtc-ti-k3.c b/drivers/rtc/rtc-ti-k3.c
index 8df00319cb6b..99fdf1192675 100644
--- a/drivers/rtc/rtc-ti-k3.c
+++ b/drivers/rtc/rtc-ti-k3.c
@@ -613,6 +613,13 @@ static int ti_k3_rtc_probe(struct platform_device *pdev)
 	else
 		device_set_wakeup_capable(dev, true);
 
+	/*
+	 * TI K3 RTC has no battery backup in typical configurations.
+	 * Mark time as invalid to prevent hctosys from overwriting
+	 * correct system time (from bootloader/NTP) with invalid RTC value.
+	 */
+	priv->rtc_dev->time_is_valid = false;
+
 	ret = devm_rtc_register_device(priv->rtc_dev);
 	if (ret)
 		return ret;
-- 
2.34.1