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From:   "Wang, Peng 1. (NSB - CN/Hangzhou)" <peng.1.wang@nokia-sbell.com>
To:     "wim@linux-watchdog.org" <wim@linux-watchdog.org>,
        "linux@roeck-us.net" <linux@roeck-us.net>,
        "linux-watchdog@vger.kernel.org" <linux-watchdog@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: [PATCH] watchdog: make DesignWare watchdog allow users to set bigger
 timeout value
Thread-Topic: [PATCH] watchdog: make DesignWare watchdog allow users to set
 bigger timeout value
Thread-Index: AdWfimD0awmuxWORQi2dTd1MQDV31A==
Date:   Wed, 20 Nov 2019 10:07:57 +0000
Message-ID: <13477f08400047c1b32030b2680a4241@nokia-sbell.com>
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From 1d051b7c081083751dc0bab97d3ab9efbba0f4a7 Mon Sep 17 00:00:00 2001
From: Peng Wang <peng.1.wang@nokia-sbell.com>
Date: Wed, 20 Nov 2019 15:12:59 +0800
Subject: [PATCH] watchdog: make DesignWare watchdog allow users to set bigger
 timeout value

watchdog_dev.c provides means to allow users to set bigger timeout value
than HW can support, make DesignWare watchdog align with this.

Signed-off-by: Peng Wang <peng.1.wang@nokia-sbell.com>
---
 drivers/watchdog/dw_wdt.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index fef7c61..8911e5e 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -113,8 +113,15 @@ static int dw_wdt_set_timeout(struct watchdog_device *wdd, unsigned int top_s)
 	 */
 	writel(top_val | top_val << WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT,
 	       dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
-
-	wdd->timeout = dw_wdt_top_in_seconds(dw_wdt, top_val);
+    
+    /*
+     * In case users set bigger timeout value than HW can support,
+     * kernel(watchdog_dev.c) helps to feed watchdog before 
+     * wdd->timeout
+     */
+    if ( wdd->timeout * 1000 <= wdd->max_hw_heartbeat_ms ) {
+	    wdd->timeout = dw_wdt_top_in_seconds(dw_wdt, top_val);
+    }
 
 	return 0;
 }
-- 
1.8.3.1