[PATCH] ar7: register watchdog driver only if enabled in hardware configuration

[Florian Fainelli <florian@openwrt.org>]

This patch checks if the watchdog enable bit is set in the DCL
register meaning that the hardware watchdog actually works and
if so, register the ar7_wdt platform_device.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
---
diff --git a/arch/mips/ar7/platform.c b/arch/mips/ar7/platform.c
index e2278c0..835f3f0 100644
--- a/arch/mips/ar7/platform.c
+++ b/arch/mips/ar7/platform.c
@@ -503,6 +503,7 @@ static int __init ar7_register_devices(void)
 {
 	u16 chip_id;
 	int res;
+	u32 *bootcr, val;
 #ifdef CONFIG_SERIAL_8250
 	static struct uart_port uart_port[2];
 
@@ -595,7 +596,13 @@ static int __init ar7_register_devices(void)
 
 	ar7_wdt_res.end = ar7_wdt_res.start + 0x20;
 
-	res = platform_device_register(&ar7_wdt);
+	bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4);
+	val = *bootcr;
+	iounmap(bootcr);
+
+	/* Register watchdog only if enabled in hardware */
+	if (val & AR7_WDT_HW_ENA)
+		res = platform_device_register(&ar7_wdt);
 
 	return res;
 }
diff --git a/arch/mips/include/asm/mach-ar7/ar7.h b/arch/mips/include/asm/mach-ar7/ar7.h
index de71694..21cbbc7 100644
--- a/arch/mips/include/asm/mach-ar7/ar7.h
+++ b/arch/mips/include/asm/mach-ar7/ar7.h
@@ -78,6 +78,9 @@
 #define AR7_REF_CLOCK	25000000
 #define AR7_XTAL_CLOCK	24000000
 
+/* DCL */
+#define AR7_WDT_HW_ENA	0x10
+
 struct plat_cpmac_data {
 	int reset_bit;
 	int power_bit;