[PATCH v2] watchdog: imx2_wdt: add support for WDOG_B signal generation

Uwe Kleine-König u.kleine-koenig at pengutronix.de
Sun Jul 20 23:30:34 PDT 2014


On Fri, Jul 18, 2014 at 01:38:30PM +0200, Markus Niebel wrote:
> From: Markus Niebel <Markus.Niebel at tq-group.com>
> 
> Watchdog unit of i.MX supports output of a signal at
> watchdog shutdown. This feature can be useful to signal an
> external supevisor that a watchdog reset occured.
supervisor

> Support this feature as an option via devicetree.
> 
> Signed-off-by: Markus Niebel <Markus.Niebel at tq-group.com>
> ---
> History
> 
> v2:
> Fix incorrect sent patch
> - add include of.h
> - fix missing if in probe
> 
>  .../devicetree/bindings/watchdog/fsl-imx-wdt.txt   |    3 +++
>  drivers/watchdog/imx2_wdt.c                        |   11 +++++++++--
>  2 files changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt
> index 2144af1..cb759cd 100644
> --- a/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt
> +++ b/Documentation/devicetree/bindings/watchdog/fsl-imx-wdt.txt
> @@ -5,6 +5,9 @@ Required properties:
>  - reg : Should contain WDT registers location and length
>  - interrupts : Should contain WDT interrupt
>  
> +Optional properties:
> +- fsl,use-wre: set if watchdog reset out (WDOG_B) signal shall be asserted
> +
>  Examples:
>  
>  wdt at 73f98000 {
> diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
> index 9d4874f..bde96db 100644
> --- a/drivers/watchdog/imx2_wdt.c
> +++ b/drivers/watchdog/imx2_wdt.c
> @@ -58,6 +58,7 @@ struct imx2_wdt_device {
>  	struct regmap *regmap;
>  	struct timer_list timer;	/* Pings the watchdog when closed */
>  	struct watchdog_device wdog;
> +	unsigned int use_wre:1;		/* enable WRE feature */
>  };
>  
>  static bool nowayout = WATCHDOG_NOWAYOUT;
> @@ -88,7 +89,10 @@ static inline void imx2_wdt_setup(struct watchdog_device *wdog)
>  	/* Strip the old watchdog Time-Out value */
>  	val &= ~IMX2_WDT_WCR_WT;
>  	/* Generate reset if WDOG times out */
> -	val &= ~IMX2_WDT_WCR_WRE;
> +	if (wdev->use_wre)
> +		val |= IMX2_WDT_WCR_WRE;
> +	else
> +		val &= ~IMX2_WDT_WCR_WRE;
>  	/* Keep Watchdog Disabled */
>  	val &= ~IMX2_WDT_WCR_WDE;
>  	/* Set the watchdog's Time-Out value */
> @@ -219,6 +223,9 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
>  		return PTR_ERR(wdev->clk);
>  	}
>  
> +	if (of_property_read_bool(pdev->dev.of_node, "fsl,use-wre"))
> +		wdev->use_wre = 1;
> +
>  	wdog			= &wdev->wdog;
>  	wdog->info		= &imx2_wdt_info;
>  	wdog->ops		= &imx2_wdt_ops;
> @@ -226,7 +233,7 @@ static int __init imx2_wdt_probe(struct platform_device *pdev)
>  	wdog->max_timeout	= IMX2_WDT_MAX_TIME;
>  
>  	clk_prepare_enable(wdev->clk);
> -
> + 
Don't add a space here.

Did you check that this feature works on all cpus that use this driver?
On which of them did you test your change?

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |



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