Merge git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  [WATCHDOG] Fix COH 901 327 watchdog enablement

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/watchdog/coh901327_wdt.c b/drivers/watchdog/coh901327_wdt.c
index fecb307d28e9..aec7cefdef21 100644
--- a/drivers/watchdog/coh901327_wdt.c
+++ b/drivers/watchdog/coh901327_wdt.c
@@ -18,6 +18,7 @@
 #include <linux/bitops.h>
 #include <linux/uaccess.h>
 #include <linux/clk.h>
+#include <linux/delay.h>
 
 #define DRV_NAME "WDOG COH 901 327"
 
@@ -92,6 +93,8 @@ static struct clk *clk;
 static void coh901327_enable(u16 timeout)
 {
         u16 val;
+        unsigned long freq;
+        unsigned long delay_ns;
 
         clk_enable(clk);
         /* Restart timer if it is disabled */
@@ -102,6 +105,14 @@ static void coh901327_enable(u16 timeout)
         /* Acknowledge any pending interrupt so it doesn't just fire off */
         writew(U300_WDOG_IER_WILL_BARK_IRQ_ACK_ENABLE,
                virtbase + U300_WDOG_IER);
+        /*
+         * The interrupt is cleared in the 32 kHz clock domain.
+         * Wait 3 32 kHz cycles for it to take effect
+         */
+        freq = clk_get_rate(clk);
+        delay_ns = (1000000000 + freq - 1) / freq; /* Freq to ns and round up */
+        delay_ns = 3 * delay_ns; /* Wait 3 cycles */
+        ndelay(delay_ns);
         /* Enable the watchdog interrupt */
         writew(U300_WDOG_IMR_WILL_BARK_IRQ_ENABLE, virtbase + U300_WDOG_IMR);
         /* Activate the watchdog timer */