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

Hello,

On Mon, Sep 26, 2016 at 08:27:59AM +0200, Uwe Kleine-K?nig wrote:

On Mon, Sep 26, 2016 at 03:39:21AM +0300, Vladimir Zapolskiy wrote:

quoted

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@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?

I forgot in the mail at the other end of this thread that the dti were
already addressed. I (implicitly) wrote there that fsl,imx35-wdt should
be the new compatible describing the wdt with misc register. Picking
imx25 (as you did) works, too, but e.g. the CSPI device has

	compatible = "fsl,imx25-cspi", "fsl,imx35-cspi";

on the i.MX25 and

	compatible = "fsl,imx35-cspi";

on the i.MX35. So I think we should pick i.MX35 here, too, as the one
giving its name.

Best regards
Uwe

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