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+* Atmel Watchdog Timers
+
+** at91sam9-wdt
+
+Required properties:
+- compatible: must be "atmel,at91sam9260-wdt".
+- reg: physical base address of the controller and length of memory mapped
+ region.
+- clocks: phandle to input clock.
+
+Optional properties:
+- timeout-sec: contains the watchdog timeout in seconds.
+- interrupts : Should contain WDT interrupt.
+- atmel,max-heartbeat-sec : Should contain the maximum heartbeat value in
+ seconds. This value should be less or equal to 16. It is used to
+ compute the WDV field.
+- atmel,min-heartbeat-sec : Should contain the minimum heartbeat value in
+ seconds. This value must be smaller than the max-heartbeat-sec value.
+ It is used to compute the WDD field.
+- atmel,watchdog-type : Should be "hardware" or "software". Hardware watchdog
+ use the at91 watchdog reset. Software watchdog use the watchdog
+ interrupt to trigger a software reset.
+- atmel,reset-type : Should be "proc" or "all".
+ "all" : assert peripherals and processor reset signals
+ "proc" : assert the processor reset signal
+ This is valid only when using "hardware" watchdog.
+- atmel,disable : Should be present if you want to disable the watchdog.
+- atmel,idle-halt : Should be present if you want to stop the watchdog when
+ entering idle state.
+ CAUTION: This property should be used with care, it actually makes the
+ watchdog not counting when the CPU is in idle state, therefore the
+ watchdog reset time depends on mean CPU usage and will not reset at all
+ if the CPU stop working while it is in idle state, which is probably
+ not what you want.
+- atmel,dbg-halt : Should be present if you want to stop the watchdog when
+ entering debug state.
+
+Example:
+ watchdog@fffffd40 {
+ compatible = "atmel,at91sam9260-wdt";
+ reg = <0xfffffd40 0x10>;
+ interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ clocks = <&clk32k>;
+ timeout-sec = <15>;
+ atmel,watchdog-type = "hardware";
+ atmel,reset-type = "all";
+ atmel,dbg-halt;
+ atmel,idle-halt;
+ atmel,max-heartbeat-sec = <16>;
+ atmel,min-heartbeat-sec = <0>;
+ };