ENGR00162115 [WDOG]Should suspend timer in LPM

We should set the WDOG timer to suspend in low
power mode, or when system suspend, wdog will continue
to run, and reset the system. This WCR_WDZST is a write
once-only register.

Signed-off-by: Anson Huang <b20788@freescale.com>

diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index 86f7cac1026c9c0de69ef0180398e71ecfcbe660..ad2a40fefc6cb491807e39845bfdcec344c97b0f 100644 (file)
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -41,6 +41,7 @@
 #define IMX2_WDT_WCR_WT                (0xFF << 8)     /* -> Watchdog Timeout Field */
 #define IMX2_WDT_WCR_WRE       (1 << 3)        /* -> WDOG Reset Enable */
 #define IMX2_WDT_WCR_WDE       (1 << 2)        /* -> Watchdog Enable */
+#define IMX2_WDT_WCR_WDZST     (1 << 0)        /* -> Watchdog timer Suspend */
 
 #define IMX2_WDT_WSR           0x02            /* Service Register */
 #define IMX2_WDT_SEQ1          0x5555          /* -> service sequence 1 */
@@ -85,6 +86,8 @@ static inline void imx2_wdt_setup(void)
 {
        u16 val = __raw_readw(imx2_wdt.base + IMX2_WDT_WCR);
 
+       /* Suspend watch dog timer in low power mode, write once-only */
+       val |= IMX2_WDT_WCR_WDZST;
        /* Strip the old watchdog Time-Out value */
        val &= ~IMX2_WDT_WCR_WT;
        /* Generate reset if WDOG times out */