[RFC PATCH 2/2] ARM: i.MX: dts: add fsl, imx25-wdt compatible to all relevant watchdog nodes

[Uwe Kleine-König]

Hello Vladimir,

On Mon, Sep 26, 2016 at 03:39:21AM +0300, Vladimir Zapolskiy wrote:
> Watchdog device controller found on all modern SoCs from i.MX series
> and firstly introduced in i.MX25 is not one in one compatible with the
> watchdog controllers on i.MX21, i.MX27 and i.MX31, the latter
> controlles don't have WICR (and pretimeout notification support) and
> WMCR registers. To get benefit from the more advanced watchdog device
> and to avoid operations over non-existing registers on legacy SoCs add
> fsl,imx25-wdt compatible to descriptions of all i.MX25 compatible
> watchdog controllers.
> 
> Signed-off-by: Vladimir Zapolskiy <vz at mleia.com>
> ---
>  arch/arm/boot/dts/imx35.dtsi   |  3 ++-
>  arch/arm/boot/dts/imx50.dtsi   |  3 ++-
>  arch/arm/boot/dts/imx51.dtsi   |  6 ++++--
>  arch/arm/boot/dts/imx53.dtsi   |  6 ++++--
>  arch/arm/boot/dts/imx6qdl.dtsi |  6 ++++--
>  arch/arm/boot/dts/imx6sl.dtsi  |  6 ++++--
>  arch/arm/boot/dts/imx6sx.dtsi  |  9 ++++++---
>  arch/arm/boot/dts/imx6ul.dtsi  |  6 ++++--
>  arch/arm/boot/dts/imx7s.dtsi   | 12 ++++++++----
>  arch/arm/boot/dts/ls1021a.dtsi |  2 +-
>  arch/arm/boot/dts/vfxxx.dtsi   |  3 ++-
>  11 files changed, 41 insertions(+), 21 deletions(-)
> 
> diff --git a/arch/arm/boot/dts/imx35.dtsi b/arch/arm/boot/dts/imx35.dtsi
> index 490b7b4..8fd4482 100644
> --- a/arch/arm/boot/dts/imx35.dtsi
> +++ b/arch/arm/boot/dts/imx35.dtsi
> @@ -284,7 +284,8 @@
>  			};
>  
>  			wdog: wdog at 53fdc000 {
> -				compatible = "fsl,imx35-wdt", "fsl,imx21-wdt";
> +				compatible = "fsl,imx35-wdt", "fsl,imx25-wdt",
> +					     "fsl,imx21-wdt";

When this is used on an old kernel that doesn't know about fsl,imx25-wdt
this picks up the imx21 driver logic. As this is wrong I think you
should drop imx21-wdt here. Can one of the dt-people comfirm?

Best regards
Uwe

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