[PATCH 2/2] drivers/watchdog: ASPEED reference dev tree properties for config

[Christopher Bostic <cbostic@linux.vnet.ibm.com>]

Reference the system device tree when configuring the watchdog.
Configure for external signal generation if optional attribute
'external-signal' is present in device tree.  Configure for
reset system after timeout if the optional attribute
'no-system-reset' is not present.  Disabling system reset may be
required in situations where one of the other watchdogs in the
systems is responsible for this.

Signed-off-by: Christopher Bostic <cbostic@linux.vnet.ibm.com>
---
 drivers/watchdog/aspeed_wdt.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index 1c65258..9deb4be 100644
--- a/drivers/watchdog/aspeed_wdt.c
+++ b/drivers/watchdog/aspeed_wdt.c
@@ -140,6 +140,7 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
 {
 	struct aspeed_wdt *wdt;
 	struct resource *res;
+	struct device_node *np;
 	int ret;
 
 	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
@@ -170,8 +171,16 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
 	 * the SOC and not the full chip
 	 */
 	wdt->ctrl = WDT_CTRL_RESET_MODE_SOC |
-		WDT_CTRL_1MHZ_CLK |
-		WDT_CTRL_RESET_SYSTEM;
+		WDT_CTRL_1MHZ_CLK;
+
+	np = pdev->dev.of_node;
+	if (np && !of_get_property(np, "no-system-reset", NULL))
+		wdt->ctrl |= WDT_CTRL_RESET_SYSTEM;
+
+	if (np && of_get_property(np, "external-signal", NULL))
+		wdt->ctrl |= WDT_CTRL_WDT_EXT;
+
+	writel(wdt->ctrl, wdt->base + WDT_CTRL);
 
 	if (readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE)  {
 		aspeed_wdt_start(&wdt->wdd);
-- 
1.8.2.2