X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=drivers%2Fbase%2Fpower%2Ftrace.c;h=1cda505d6a852bb9b9e698a9c2788e5def59f30e;hb=19d37ce2a7159ee30bd59d14fe5fe13c932bd5b7;hp=efec10b49d59a72234ec3544b63edd9d5ab144c4;hpb=2ab704a47e0f27df758840a589aec3298dbb98dd;p=karo-tx-linux.git

diff --git a/drivers/base/power/trace.c b/drivers/base/power/trace.c
index efec10b49d59..1cda505d6a85 100644
--- a/drivers/base/power/trace.c
+++ b/drivers/base/power/trace.c
@@ -10,6 +10,7 @@
 #include <linux/pm-trace.h>
 #include <linux/export.h>
 #include <linux/rtc.h>
+#include <linux/suspend.h>
 
 #include <linux/mc146818rtc.h>
 
@@ -74,6 +75,9 @@
 
 #define DEVSEED (7919)
 
+bool pm_trace_rtc_abused __read_mostly;
+EXPORT_SYMBOL_GPL(pm_trace_rtc_abused);
+
 static unsigned int dev_hash_value;
 
 static int set_magic_time(unsigned int user, unsigned int file, unsigned int device)
@@ -104,6 +108,7 @@ static int set_magic_time(unsigned int user, unsigned int file, unsigned int dev
 	time.tm_min = (n % 20) * 3;
 	n /= 20;
 	mc146818_set_time(&time);
+	pm_trace_rtc_abused = true;
 	return n ? -1 : 0;
 }
 
@@ -239,9 +244,31 @@ int show_trace_dev_match(char *buf, size_t size)
 	return ret;
 }
 
+static int
+pm_trace_notify(struct notifier_block *nb, unsigned long mode, void *_unused)
+{
+	switch (mode) {
+	case PM_POST_HIBERNATION:
+	case PM_POST_SUSPEND:
+		if (pm_trace_rtc_abused) {
+			pm_trace_rtc_abused = false;
+			pr_warn("Possible incorrect RTC due to pm_trace, please use 'ntpdate' or 'rdate' to reset it.\n");
+		}
+		break;
+	default:
+		break;
+	}
+	return 0;
+}
+
+static struct notifier_block pm_trace_nb = {
+	.notifier_call = pm_trace_notify,
+};
+
 static int early_resume_init(void)
 {
 	hash_value_early_read = read_magic_time();
+	register_pm_notifier(&pm_trace_nb);
 	return 0;
 }