Patch "rtc: s35390a: make sure all members in the output are set" has been added to the 3.18-stable tree

This is a note to let you know that I've just added the patch titled

rtc: s35390a: make sure all members in the output are set

to the 3.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:

     rtc-s35390a-make-sure-all-members-in-the-output-are-set.patch

and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= <[email protected]>
Date: Mon, 3 Apr 2017 23:32:38 +0200
Subject: rtc: s35390a: make sure all members in the output are set
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From: Uwe Kleine-König <[email protected]>

commit fdd4bc9313e59a1757cfc8ac5836cff55ec03eeb in 4.4-stable.

The rtc core calls the .read_alarm with all fields initialized to 0. As the s35390a driver doesn't touch some fields the returned date is interpreted as a date in January 1900. So make sure all fields are set to -1; some of them are then overwritten with the right data depending on the hardware state.

In mainline this is done by commit d68778b80dd7 ("rtc: initialize output parameter for read alarm to "uninitialized"") in the core. This is considered to dangerous for stable as it might have side effects for other rtc drivers that might for example rely on alarm->time.tm_sec being initialized to 0.

---
 drivers/rtc/rtc-s35390a.c |   14 ++++++++++++++
 1 file changed, 14 insertions(+)

@@ -267,6 +267,20 @@ static int s35390a_read_alarm(struct i2c
 	char buf[3], sts;
 	int i, err;
 
+	/*
+	 * initialize all members to -1 to signal the core that they are not
+	 * defined by the hardware.
+	 */
+	alm->time.tm_sec = -1;
+	alm->time.tm_min = -1;
+	alm->time.tm_hour = -1;
+	alm->time.tm_mday = -1;
+	alm->time.tm_mon = -1;
+	alm->time.tm_year = -1;
+	alm->time.tm_wday = -1;
+	alm->time.tm_yday = -1;
+	alm->time.tm_isdst = -1;
+
 	err = s35390a_get_reg(s35390a, S35390A_CMD_STATUS2, &sts, sizeof(sts));
 	if (err < 0)
 		return err;

Patches currently in stable-queue which might be from [email protected] are

queue-3.18/rtc-s35390a-improve-irq-handling.patch queue-3.18/rtc-s35390a-fix-reading-out-alarm.patch queue-3.18/rtc-s35390a-make-sure-all-members-in-the-output-are-set.patch queue-3.18/rtc-s35390a-implement-reset-routine-as-suggested-by-the-reference.patch