[PATCH] ARM: dts: imx7d-flex-concentrator: fix pcf2127 reset

[PATCH] ARM: dts: imx7d-flex-concentrator: fix pcf2127 reset

[Bruno Thomsen]

RTC pcf2127 device driver has changed default behaviour of the watchdog
feature in v5.11-rc1. Now you need to explicitly enable it with a
device tree property, "reset-source", when used in the board design.

Fixes: 71ac13457d9d ("rtc: pcf2127: only use watchdog when explicitly available")

Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
Cc: Bruno Thomsen <bth@kamstrup.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
---
 arch/arm/boot/dts/imx7d-flex-concentrator.dts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/imx7d-flex-concentrator.dts b/arch/arm/boot/dts/imx7d-flex-concentrator.dts
index 84b095279e65..bd6b5285aa8d 100644
--- a/arch/arm/boot/dts/imx7d-flex-concentrator.dts
+++ b/arch/arm/boot/dts/imx7d-flex-concentrator.dts
@@ -115,6 +115,7 @@ pcf2127: rtc@0 {
 		compatible = "nxp,pcf2127";
 		reg = <0>;
 		spi-max-frequency = <2000000>;
+		reset-source;
 	};
 };
 

base-commit: 7c53f6b671f4aba70ff15e1b05148b10d58c2837
-- 
2.29.2

Re: [PATCH] ARM: dts: imx7d-flex-concentrator: fix pcf2127 reset

[Alexandre Belloni]

On 11/01/2021 16:15:37+0100, Bruno Thomsen wrote:
> RTC pcf2127 device driver has changed default behaviour of the watchdog
> feature in v5.11-rc1. Now you need to explicitly enable it with a
> device tree property, "reset-source", when used in the board design.
> 
> Fixes: 71ac13457d9d ("rtc: pcf2127: only use watchdog when explicitly available")
> 
> Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
> Cc: Bruno Thomsen <bth@kamstrup.com>
> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Reviewed-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

> ---
>  arch/arm/boot/dts/imx7d-flex-concentrator.dts | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/boot/dts/imx7d-flex-concentrator.dts b/arch/arm/boot/dts/imx7d-flex-concentrator.dts
> index 84b095279e65..bd6b5285aa8d 100644
> --- a/arch/arm/boot/dts/imx7d-flex-concentrator.dts
> +++ b/arch/arm/boot/dts/imx7d-flex-concentrator.dts
> @@ -115,6 +115,7 @@ pcf2127: rtc@0 {
>  		compatible = "nxp,pcf2127";
>  		reg = <0>;
>  		spi-max-frequency = <2000000>;
> +		reset-source;
>  	};
>  };
>  
> 
> base-commit: 7c53f6b671f4aba70ff15e1b05148b10d58c2837
> -- 
> 2.29.2
> 

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH] ARM: dts: imx7d-flex-concentrator: fix pcf2127 reset

[Shawn Guo]

On Mon, Jan 11, 2021 at 04:15:37PM +0100, Bruno Thomsen wrote:
> RTC pcf2127 device driver has changed default behaviour of the watchdog
> feature in v5.11-rc1. Now you need to explicitly enable it with a
> device tree property, "reset-source", when used in the board design.

It sound that the existing DTBs are broken by this default behaviour
change?

> 
> Fixes: 71ac13457d9d ("rtc: pcf2127: only use watchdog when explicitly available")
> 
> Signed-off-by: Bruno Thomsen <bruno.thomsen@gmail.com>
> Cc: Bruno Thomsen <bth@kamstrup.com>
> Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
> Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
> Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>

Applied, thanks.

Shawn

> ---
>  arch/arm/boot/dts/imx7d-flex-concentrator.dts | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/boot/dts/imx7d-flex-concentrator.dts b/arch/arm/boot/dts/imx7d-flex-concentrator.dts
> index 84b095279e65..bd6b5285aa8d 100644
> --- a/arch/arm/boot/dts/imx7d-flex-concentrator.dts
> +++ b/arch/arm/boot/dts/imx7d-flex-concentrator.dts
> @@ -115,6 +115,7 @@ pcf2127: rtc@0 {
>  		compatible = "nxp,pcf2127";
>  		reg = <0>;
>  		spi-max-frequency = <2000000>;
> +		reset-source;
>  	};
>  };
>  
> 
> base-commit: 7c53f6b671f4aba70ff15e1b05148b10d58c2837
> -- 
> 2.29.2
> 

Re: [PATCH] ARM: dts: imx7d-flex-concentrator: fix pcf2127 reset

[Uwe Kleine-König]

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On Mon, Jan 18, 2021 at 02:32:53PM +0800, Shawn Guo wrote:
> On Mon, Jan 11, 2021 at 04:15:37PM +0100, Bruno Thomsen wrote:
> > RTC pcf2127 device driver has changed default behaviour of the watchdog
> > feature in v5.11-rc1. Now you need to explicitly enable it with a
> > device tree property, "reset-source", when used in the board design.
> 
> It sound that the existing DTBs are broken by this default behaviour
> change?

I didn't do a representative research, but I expect that there are only
very few machines that have a working watchdog setup using the pcf2127.
All other machines were surprised by commit

	0e735eaae165 ("rtc: pcf2127: add watchdog feature support")

because they suddenly had a non-functional watchdog device. The
alternative would be to "fix" the device trees of all these machines to
restore pre-v5.4-rc1 behaviour. This is IMHO worse.

Best regards
Uwe

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

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