From 0b145f91d8fdbe39900356c8ad3ba4e41ce95fab Mon Sep 17 00:00:00 2001
From: Steve Muckle <smuckle@google.com>
Date: Thu, 20 Feb 2020 11:51:05 -0800
Subject: [PATCH] ANDROID: rtc: class: support hctosys from modular RTC drivers

In order to support setting the system time from modular RTC drivers
via the hctosys mechanism, check at the end of RTC device registration
for whether the time should be synced, rather than once at late init.

Bug: 144103362
Bug: 143046457
Change-Id: I65d2fd14e075a65f2a23e1268b02c907c5245fb8
Signed-off-by: Steve Muckle <smuckle@google.com>
---
 drivers/rtc/class.c    | 5 +++++
 drivers/rtc/hctosys.c  | 4 +---
 drivers/rtc/rtc-core.h | 4 ++++
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index 0fca4d74c76b..9d3ffc217163 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -527,6 +527,11 @@ int __rtc_register_device(struct module *owner, struct rtc_device *rtc)
 	dev_info(rtc->dev.parent, "registered as %s\n",
 		 dev_name(&rtc->dev));
 
+#ifdef CONFIG_RTC_HCTOSYS_DEVICE
+	if (!strcmp(dev_name(&rtc->dev), CONFIG_RTC_HCTOSYS_DEVICE))
+		rtc_hctosys();
+#endif
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(__rtc_register_device);
diff --git a/drivers/rtc/hctosys.c b/drivers/rtc/hctosys.c
index b9ec4a16db1f..02b71afa330c 100644
--- a/drivers/rtc/hctosys.c
+++ b/drivers/rtc/hctosys.c
@@ -24,7 +24,7 @@
  * the best guess is to add 0.5s.
  */
 
-static int __init rtc_hctosys(void)
+int rtc_hctosys(void)
 {
 	int err = -ENODEV;
 	struct rtc_time tm;
@@ -73,5 +73,3 @@ err_open:
 
 	return err;
 }
-
-late_initcall(rtc_hctosys);
diff --git a/drivers/rtc/rtc-core.h b/drivers/rtc/rtc-core.h
index ccc17a2e293d..57a8a18e6eb4 100644
--- a/drivers/rtc/rtc-core.h
+++ b/drivers/rtc/rtc-core.h
@@ -60,3 +60,7 @@ int rtc_add_groups(struct rtc_device *rtc, const struct attribute_group **grps)
 	return 0;
 }
 #endif
+
+#ifdef CONFIG_RTC_HCTOSYS
+extern int rtc_hctosys(void);
+#endif