Re: [PATCH 12/13] ARM: dts: stm32: fix DSI port node on STM32MP15

From: Alexandre TORGUE
Date: Thu Apr 15 2021 - 08:23:54 EST


Hi Ahmad

On 4/15/21 12:43 PM, Ahmad Fatoum wrote:
Hi,

On 15.04.21 12:10, Alexandre Torgue wrote:
Running "make dtbs_check W=1", some warnings are reported concerning
DSI. This patch reorder DSI nodes to avoid:

soc/dsi@5a000000: unnecessary #address-cells/#size-cells without
"ranges" or child "reg" property

This reverts parts of commit 9c32f980d9 ("ARM: dts: stm32: preset
stm32mp15x video #address- and #size-cells"):
The cell count for address and size is defined by the binding and not
something a board would change. Avoid each board adding this
boilerplate by having the cell size specification in the SoC DTSI.

The DSI can have child nodes with a unit address (e.g. a panel) and ones
without (ports { } container). ports is described in the dtsi, panels are
described in the dts if available.

Apparently, the checker is fine with
ports {
#address-cells = <1>;
#size-cells = <0>;
};

I think my rationale for the patch above was sound, so I think the checker
taking offense at the DSI cells here should be considered a false positive.

If it's a "false positive" warning then we need to find a way to not print it out. Else, it'll be difficult to distinguish which warnings are "normal" and which are not. This question could also be applied to patch[3].

Arnd, Rob what is your feeling about this case ?

thanks
alex



Thanks,
Ahmad


Signed-off-by: Alexandre Torgue <alexandre.torgue@xxxxxxxxxxx>

diff --git a/arch/arm/boot/dts/stm32mp157.dtsi b/arch/arm/boot/dts/stm32mp157.dtsi
index 54e73ccea446..c355fcf26ec3 100644
--- a/arch/arm/boot/dts/stm32mp157.dtsi
+++ b/arch/arm/boot/dts/stm32mp157.dtsi
@@ -24,8 +24,6 @@
clock-names = "pclk", "ref", "px_clk";
resets = <&rcc DSI_R>;
reset-names = "apb";
- #address-cells = <1>;
- #size-cells = <0>;
status = "disabled";
ports {
diff --git a/arch/arm/boot/dts/stm32mp157c-dk2.dts b/arch/arm/boot/dts/stm32mp157c-dk2.dts
index 19ef475a48fc..763dde1dbbaf 100644
--- a/arch/arm/boot/dts/stm32mp157c-dk2.dts
+++ b/arch/arm/boot/dts/stm32mp157c-dk2.dts
@@ -36,6 +36,8 @@
&dsi {
status = "okay";
phy-dsi-supply = <&reg18>;
+ #address-cells = <1>;
+ #size-cells = <0>;
ports {
port@0 {
diff --git a/arch/arm/boot/dts/stm32mp157c-ev1.dts b/arch/arm/boot/dts/stm32mp157c-ev1.dts
index 6fe5b0fee7c4..4625bb58cc6d 100644
--- a/arch/arm/boot/dts/stm32mp157c-ev1.dts
+++ b/arch/arm/boot/dts/stm32mp157c-ev1.dts
@@ -102,6 +102,8 @@
&dsi {
phy-dsi-supply = <&reg18>;
status = "okay";
+ #address-cells = <1>;
+ #size-cells = <0>;
ports {
port@0 {