[PATCH v2 1/2] time: Add the common weak version of update_persistent_clock()

[Xunlei Pang <xlpang@126.com>]

From: Xunlei Pang <pang.xunlei@linaro.org>

The weak update_persistent_clock64() calls update_persistent_clock(),
if the architecture defines a update_persistent_clock64() to replace
and remove its update_persistent_clock() version, the compiler will
throw an undefined symbol error, that is, any arch that switches to
update_persistent_clock64() will have this issue.

So, we should add the common weak update_persistent_clock().

Cc: John Stultz <john.stultz@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Xunlei Pang <pang.xunlei@linaro.org>
---
 kernel/time/ntp.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index fb4d98c..df68cb8 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -487,6 +487,11 @@ out:
 }
 
 #ifdef CONFIG_GENERIC_CMOS_UPDATE
+int __weak update_persistent_clock(struct timespec now)
+{
+	return -ENODEV;
+}
+
 int __weak update_persistent_clock64(struct timespec64 now64)
 {
 	struct timespec now;
-- 
1.9.1