[PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[Dragan Simic]

Sprinkle a few commonly used aliases onto the PineTab2 dtsi file, to improve
its readability a bit, to make it easier to refer to the actual nodes later,
if needed, and to add a bit more detail to some of the labels.

No functional changes are introduced, which was validated by decompiling and
comparing all affected board dtb files before and after these changes.  When
compared with the decompiled original dtb files, some of the phandles in the
updated dtb files have different values, and the updated dtb files contain
some additional phandles and additional symbols that come from the introduced
aliases, but they still effectively remain the same as the originals.

Suggested-by: Diederik de Haas <didi.debian@cknow.org>
Signed-off-by: Dragan Simic <dsimic@manjaro.org>
---

Notes:
    This patch wasn't tested on a PineTab2 before it was submitted to the
    mailing list, because I don't have that device, but Diederik has already
    agreed to test this patch on his PineTab2 and provide feedback.

 arch/arm64/boot/dts/rockchip/rk3566-pinetab2.dtsi | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3566-pinetab2.dtsi b/arch/arm64/boot/dts/rockchip/rk3566-pinetab2.dtsi
index db40281eafbe..04d98715ae6e 100644
--- a/arch/arm64/boot/dts/rockchip/rk3566-pinetab2.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3566-pinetab2.dtsi
@@ -41,7 +41,7 @@ button-vol-down {
 		};
 	};
 
-	backlight: backlight {
+	backlight: backlight-dsi {
 		compatible = "pwm-backlight";
 		pwms = <&pwm4 0 25000 0>;
 		brightness-levels = <20 220>;
@@ -551,20 +551,20 @@ regulator-state-mem {
 			};
 		};
 
-		charger {
+		rk817_charger: charger {
 			monitored-battery = <&battery>;
 			rockchip,resistor-sense-micro-ohms = <10000>;
 			rockchip,sleep-enter-current-microamp = <300000>;
 			rockchip,sleep-filter-current-microamp = <100000>;
 		};
 	};
 };
 
 &i2c1 {
 	clock-frequency = <400000>;
 	status = "okay";
 
-	touchscreen@5d {
+	touchscreen: touchscreen@5d {
 		compatible = "goodix,gt911";
 		reg = <0x5d>;
 		interrupt-parent = <&gpio0>;
@@ -583,13 +583,13 @@ &i2c2 {
 	pinctrl-0 = <&i2c2m1_xfer>;
 	status = "okay";
 
-	vcm@c {
+	vcm: vcm@c {
 		compatible = "dongwoon,dw9714";
 		reg = <0x0c>;
 		vcc-supply = <&vcc1v8_dvp>;
 	};
 
-	camera@36 {
+	camerab: camera@36 {
 		compatible = "ovti,ov5648";
 		reg = <0x36>;
 		pinctrl-names = "default";
@@ -619,7 +619,7 @@ &i2c5 {
 	clock-frequency = <400000>;
 	status = "okay";
 
-	accelerometer@18 {
+	accelerometer: accelerometer@18 {
 		compatible = "silan,sc7a20";
 		reg = <0x18>;
 		interrupt-parent = <&gpio3>;

Re: [PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[Krzysztof Kozlowski]

On 05/09/2024 13:32, Dragan Simic wrote:
> Sprinkle a few commonly used aliases onto the PineTab2 dtsi file, to improve
> its readability a bit, to make it easier to refer to the actual nodes later,
> if needed, and to add a bit more detail to some of the labels.
> 
> No functional changes are introduced, which was validated by decompiling and
> comparing all affected board dtb files before and after these changes.  When
> compared with the decompiled original dtb files, some of the phandles in the
> updated dtb files have different values, and the updated dtb files contain
> some additional phandles and additional symbols that come from the introduced
> aliases, but they still effectively remain the same as the originals.
> 
> Suggested-by: Diederik de Haas <didi.debian@cknow.org>
> Signed-off-by: Dragan Simic <dsimic@manjaro.org>
> ---

Unused aliases do not improve readability, so for me this change is
making code worse without valid reason.

Best regards,
Krzysztof

Re: [PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[Dragan Simic]

Hello Krzysztof,

On 2024-09-05 13:39, Krzysztof Kozlowski wrote:
> On 05/09/2024 13:32, Dragan Simic wrote:
>> Sprinkle a few commonly used aliases onto the PineTab2 dtsi file, to 
>> improve
>> its readability a bit, to make it easier to refer to the actual nodes 
>> later,
>> if needed, and to add a bit more detail to some of the labels.
>> 
>> No functional changes are introduced, which was validated by 
>> decompiling and
>> comparing all affected board dtb files before and after these changes. 
>>  When
>> compared with the decompiled original dtb files, some of the phandles 
>> in the
>> updated dtb files have different values, and the updated dtb files 
>> contain
>> some additional phandles and additional symbols that come from the 
>> introduced
>> aliases, but they still effectively remain the same as the originals.
>> 
>> Suggested-by: Diederik de Haas <didi.debian@cknow.org>
>> Signed-off-by: Dragan Simic <dsimic@manjaro.org>
>> ---
> 
> Unused aliases do not improve readability, so for me this change is
> making code worse without valid reason.

Then why do we already have, for example, unused "rk817_charger: 
charger"
aliases in quite a few board dts(i) files?  If those are actually seen 
as
redundant, we should remove all of them.

Re: [PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[Krzysztof Kozlowski]

On 05/09/2024 13:43, Dragan Simic wrote:
> Hello Krzysztof,
> 
> On 2024-09-05 13:39, Krzysztof Kozlowski wrote:
>> On 05/09/2024 13:32, Dragan Simic wrote:
>>> Sprinkle a few commonly used aliases onto the PineTab2 dtsi file, to 
>>> improve
>>> its readability a bit, to make it easier to refer to the actual nodes 
>>> later,
>>> if needed, and to add a bit more detail to some of the labels.
>>>
>>> No functional changes are introduced, which was validated by 
>>> decompiling and
>>> comparing all affected board dtb files before and after these changes. 
>>>  When
>>> compared with the decompiled original dtb files, some of the phandles 
>>> in the
>>> updated dtb files have different values, and the updated dtb files 
>>> contain
>>> some additional phandles and additional symbols that come from the 
>>> introduced
>>> aliases, but they still effectively remain the same as the originals.
>>>
>>> Suggested-by: Diederik de Haas <didi.debian@cknow.org>
>>> Signed-off-by: Dragan Simic <dsimic@manjaro.org>
>>> ---
>>
>> Unused aliases do not improve readability, so for me this change is
>> making code worse without valid reason.
> 
> Then why do we already have, for example, unused "rk817_charger: 
> charger"
> aliases in quite a few board dts(i) files?  If those are actually seen 

Ask contributors...

> as
> redundant, we should remove all of them.

They are already there, so dropping them is close to unnecessary churn.
And quite a lot of work to investigate the reason behind EACH label.

Best regards,
Krzysztof

Re: [PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[Dragan Simic]

On 2024-09-05 13:48, Krzysztof Kozlowski wrote:
> On 05/09/2024 13:43, Dragan Simic wrote:
>> Hello Krzysztof,
>> 
>> On 2024-09-05 13:39, Krzysztof Kozlowski wrote:
>>> On 05/09/2024 13:32, Dragan Simic wrote:
>>>> Sprinkle a few commonly used aliases onto the PineTab2 dtsi file, to
>>>> improve
>>>> its readability a bit, to make it easier to refer to the actual 
>>>> nodes
>>>> later,
>>>> if needed, and to add a bit more detail to some of the labels.
>>>> 
>>>> No functional changes are introduced, which was validated by
>>>> decompiling and
>>>> comparing all affected board dtb files before and after these 
>>>> changes.
>>>>  When
>>>> compared with the decompiled original dtb files, some of the 
>>>> phandles
>>>> in the
>>>> updated dtb files have different values, and the updated dtb files
>>>> contain
>>>> some additional phandles and additional symbols that come from the
>>>> introduced
>>>> aliases, but they still effectively remain the same as the 
>>>> originals.
>>>> 
>>>> Suggested-by: Diederik de Haas <didi.debian@cknow.org>
>>>> Signed-off-by: Dragan Simic <dsimic@manjaro.org>
>>>> ---
>>> 
>>> Unused aliases do not improve readability, so for me this change is
>>> making code worse without valid reason.
>> 
>> Then why do we already have, for example, unused "rk817_charger:
>> charger"
>> aliases in quite a few board dts(i) files?  If those are actually seen
> 
> Ask contributors...

That would be a lot of work for next to nothing.  Actually, I believe
those aliases were simply copied and pasted, at least when it comes to
the "rk817_*" aliases that are unused without doubt.

>> as
>> redundant, we should remove all of them.
> 
> They are already there, so dropping them is close to unnecessary churn.
> And quite a lot of work to investigate the reason behind EACH label.

Hmm, it's true that a lot of work would be needed.  On the other hand,
how about adding these aliases to the PineTab2 dtsi for the sake of
consistency with the other similar board dts(i) files?  For example,
grepping for "rk817_charger", which is used as an alias in all other
dts(i) files for boards that use RK817, currently omits the PineTab2
dtsi.  I see that as a downside that this patch attempts to improve.

Re: [PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[Diederik de Haas]

[-- Attachment #1: Type: text/plain, Size: 1169 bytes --]

On Thu Sep 5, 2024 at 1:39 PM CEST, Krzysztof Kozlowski wrote:
> On 05/09/2024 13:32, Dragan Simic wrote:
> > Sprinkle a few commonly used aliases onto the PineTab2 dtsi file, to improve
> > its readability a bit, to make it easier to refer to the actual nodes later,
> > if needed, and to add a bit more detail to some of the labels.
> > 
> > Suggested-by: Diederik de Haas <didi.debian@cknow.org>
> > Signed-off-by: Dragan Simic <dsimic@manjaro.org>
>
> Unused aliases do not improve readability, so for me this change is
> making code worse without valid reason.

This came forth by a question from me to Dragan about a patch for
another board which doesn't have a charger defined at all (yet).
I actually have that patch (but not the HW) for a while (~1.5 year)
now and I had used `rk817_charger: charger` for that, probably because
I saw that being used everywhere else.

Then I compared it to the PineTab2 and noticed it had only `charger`, so
I asked "What should I use? With or without the alias?"
In this case the inconsistency is causing confusion (with me).

So: What should be used for that other/new board(s)?

Cheers,
  Diederik

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]

Re: [PATCH] arm64: dts: rockchip: Add a few aliases to the PineTab2 dtsi

[Heiko Stübner]

Am Donnerstag, 5. September 2024, 14:21:12 CEST schrieb Diederik de Haas:
> On Thu Sep 5, 2024 at 1:39 PM CEST, Krzysztof Kozlowski wrote:
> > On 05/09/2024 13:32, Dragan Simic wrote:
> > > Sprinkle a few commonly used aliases onto the PineTab2 dtsi file, to improve
> > > its readability a bit, to make it easier to refer to the actual nodes later,
> > > if needed, and to add a bit more detail to some of the labels.
> > > 
> > > Suggested-by: Diederik de Haas <didi.debian@cknow.org>
> > > Signed-off-by: Dragan Simic <dsimic@manjaro.org>
> >
> > Unused aliases do not improve readability, so for me this change is
> > making code worse without valid reason.
> 
> This came forth by a question from me to Dragan about a patch for
> another board which doesn't have a charger defined at all (yet).
> I actually have that patch (but not the HW) for a while (~1.5 year)
> now and I had used `rk817_charger: charger` for that, probably because
> I saw that being used everywhere else.
> 
> Then I compared it to the PineTab2 and noticed it had only `charger`, so
> I asked "What should I use? With or without the alias?"
> In this case the inconsistency is causing confusion (with me).
> 
> So: What should be used for that other/new board(s)?

As Krzysztof said, having a phandle that is never going to be used is
somewhat pointless.

Having a phandle defined for a node does not hurt anything, so having
some in a board dts is not catastrophically bad, but there is no reason
to add or remove unused ones for no reason - especially as it affects
git blame .

So in short, if you see an unused phandle in a dts _patch_, just point it
out in review.


Heiko