From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Date: Wed, 9 Nov 2022 12:15:36 +0000 (+0100)
Subject: rtc: cmos: Disable ACPI RTC event on removal
X-Git-Tag: v6.1.8~1126
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=421091ae0e27dfb29fed9ea2eecbf0100e9c7049;p=platform%2Fkernel%2Flinux-starfive.git

rtc: cmos: Disable ACPI RTC event on removal

[ Upstream commit 83ebb7b3036d151ee39a4a752018665648fc3bd4 ]

Make cmos_do_remove() drop the ACPI RTC fixed event handler so as to
prevent it from operating on stale data in case the event triggers
after driver removal.

Fixes: 311ee9c151ad ("rtc: cmos: allow using ACPI for RTC alarm instead of HPET")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Tested-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/2224609.iZASKD2KPV@kreacher
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
index 039486bf..00e2ca7 100644
--- a/drivers/rtc/rtc-cmos.c
+++ b/drivers/rtc/rtc-cmos.c
@@ -798,6 +798,14 @@ static void acpi_rtc_event_setup(struct device *dev)
 	acpi_disable_event(ACPI_EVENT_RTC, 0);
 }
 
+static void acpi_rtc_event_cleanup(void)
+{
+	if (acpi_disabled)
+		return;
+
+	acpi_remove_fixed_event_handler(ACPI_EVENT_RTC, rtc_handler);
+}
+
 static void rtc_wake_on(struct device *dev)
 {
 	acpi_clear_event(ACPI_EVENT_RTC);
@@ -884,6 +892,10 @@ static inline void acpi_rtc_event_setup(struct device *dev)
 {
 }
 
+static inline void acpi_rtc_event_cleanup(void)
+{
+}
+
 static inline void acpi_cmos_wake_setup(struct device *dev)
 {
 }
@@ -1138,6 +1150,9 @@ static void cmos_do_remove(struct device *dev)
 			hpet_unregister_irq_handler(cmos_interrupt);
 	}
 
+	if (!dev_get_platdata(dev))
+		acpi_rtc_event_cleanup();
+
 	cmos->rtc = NULL;
 
 	ports = cmos->iomem;