From: Wim Van Sebroeck <wim@iguana.be>
Date: Sat, 9 Sep 2017 17:41:24 +0200
Subject: watchdog: Revert "iTCO_wdt: all versions count down twice"
Git-commit: fc61e83a29308601e6e8a0759e24fc8fe2122692
Patch-mainline: v4.14-rc1
References: bsc#1061556

This reverts commit 1fccb73011ea8a5fa0c6d357c33fa29c695139ea.
Reported as Bug 196509 - iTCO_wdt regression reboot before timeout expire

Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Martin Wilck <mwilck@suse.com>
---
 Documentation/watchdog/watchdog-parameters.txt |  2 +-
 drivers/watchdog/iTCO_wdt.c                    | 22 ++++++++++++----------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt
index b3526365ea8e..6f9d7b418917 100644
--- a/Documentation/watchdog/watchdog-parameters.txt
+++ b/Documentation/watchdog/watchdog-parameters.txt
@@ -117,7 +117,7 @@ nowayout: Watchdog cannot be stopped once started
 -------------------------------------------------
 iTCO_wdt:
 heartbeat: Watchdog heartbeat in seconds.
-	(5<=heartbeat<=74 (TCO v1) or 1226 (TCO v2), default=30)
+	(2<heartbeat<39 (TCO v1) or 613 (TCO v2), default=30)
 nowayout: Watchdog cannot be stopped once started
 	(default=kernel config parameter)
 -------------------------------------------------
diff --git a/drivers/watchdog/iTCO_wdt.c b/drivers/watchdog/iTCO_wdt.c
index c4f65873bfa4..347f0389b089 100644
--- a/drivers/watchdog/iTCO_wdt.c
+++ b/drivers/watchdog/iTCO_wdt.c
@@ -306,15 +306,16 @@ static int iTCO_wdt_ping(struct watchdog_device *wd_dev)
 
 	iTCO_vendor_pre_keepalive(p->smi_res, wd_dev->timeout);
 
-	/* Reset the timeout status bit so that the timer
-	 * needs to count down twice again before rebooting */
-	outw(0x0008, TCO1_STS(p));	/* write 1 to clear bit */
-
 	/* Reload the timer by writing to the TCO Timer Counter register */
-	if (p->iTCO_version >= 2)
+	if (p->iTCO_version >= 2) {
 		outw(0x01, TCO_RLD(p));
-	else if (p->iTCO_version == 1)
+	} else if (p->iTCO_version == 1) {
+		/* Reset the timeout status bit so that the timer
+		 * needs to count down twice again before rebooting */
+		outw(0x0008, TCO1_STS(p));	/* write 1 to clear bit */
+
 		outb(0x01, TCO_RLD(p));
+	}
 
 	spin_unlock(&p->io_lock);
 	return 0;
@@ -327,8 +328,11 @@ static int iTCO_wdt_set_timeout(struct watchdog_device *wd_dev, unsigned int t)
 	unsigned char val8;
 	unsigned int tmrval;
 
-	/* The timer counts down twice before rebooting */
-	tmrval = seconds_to_ticks(p, t) / 2;
+	tmrval = seconds_to_ticks(p, t);
+
+	/* For TCO v1 the timer counts down twice before rebooting */
+	if (p->iTCO_version == 1)
+		tmrval /= 2;
 
 	/* from the specs: */
 	/* "Values of 0h-3h are ignored and should not be attempted" */
@@ -381,8 +385,6 @@ static unsigned int iTCO_wdt_get_timeleft(struct watchdog_device *wd_dev)
 		spin_lock(&p->io_lock);
 		val16 = inw(TCO_RLD(p));
 		val16 &= 0x3ff;
-		if (!(inw(TCO1_STS(p)) & 0x0008))
-			val16 += (inw(TCOv2_TMR(p)) & 0x3ff);
 		spin_unlock(&p->io_lock);
 
 		time_left = ticks_to_seconds(p, val16);