[PATCH v2] platform/x86/amd/pmc: Fix RTC reference leak in amd_pmc_verify_czn_rtc()

[Ma Ke]

amd_pmc_verify_czn_rtc() opens the RTC with rtc_class_open(), which
takes both a device reference and a module reference on the RTC
driver. rtc_class_close() is the matching release, but it is not
called.

Use a __free() to cleanup call on the declaration

Found by code review.

Fixes: 59348401ebed ("platform/x86: amd-pmc: Add special handling for timer based S0i3 wakeup")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Ma Ke <make_ruc2021@xxxxxxx>
---
Changes in v2:
- modified the patch, thanks for developer's suggestions.
---
 drivers/platform/x86/amd/pmc/pmc.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/platform/x86/amd/pmc/pmc.c b/drivers/platform/x86/amd/pmc/pmc.c
index 6792aa2c6187..b1ad79b22c07 100644
--- a/drivers/platform/x86/amd/pmc/pmc.c
+++ b/drivers/platform/x86/amd/pmc/pmc.c
@@ -14,6 +14,7 @@
 #include <linux/array_size.h>
 #include <linux/bitfield.h>
 #include <linux/bits.h>
+#include <linux/cleanup.h>
 #include <linux/debugfs.h>
 #include <linux/delay.h>
 #include <linux/dmi.h>
@@ -646,9 +647,11 @@ static int amd_pmc_wa_irq1(struct amd_pmc_dev *pdev)
 	return 0;
 }
 
+DEFINE_FREE(rtc_class_close, struct rtc_device *, rtc_class_close(_T));
+
 static int amd_pmc_verify_czn_rtc(struct amd_pmc_dev *pdev, u32 *arg)
 {
-	struct rtc_device *rtc_device;
+	struct rtc_device *rtc_device __free(rtc_class_close) = NULL;
 	time64_t then, now, duration;
 	struct rtc_wkalrm alarm;
 	struct rtc_time tm;
-- 
2.43.0