[PATCHv2 1/2] dts: Documentation: AT91 Watchdog, explain what atmel,idle-halt property really do

[Boris Brezillon]

On Sun, 18 Jan 2015 14:26:50 +0100
Sylvain Rochet <sylvain.rochet at finsecur.com> wrote:

> atmel,idle-halt 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
> of the CPU stop working while it is in idle state, which is probably not
> what you want.
> 
> Signed-off-by: Sylvain Rochet <sylvain.rochet at finsecur.com>

Acked-by: Boris Brezillon <boris.brezillon at free-electrons.com>

> ---
>  Documentation/devicetree/bindings/watchdog/atmel-wdt.txt | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> index f90e294..a4d8697 100644
> --- a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> +++ b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
> @@ -26,6 +26,11 @@ Optional properties:
>  - 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.
>  



-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com