The reset controller driver for the TH1520 was using the generic compatible string "thead,th1520-reset". However, the controller described by this compatible only manages the resets for the Video Output (VO) subsystem.
Using a generic compatible is confusing as it implies control over all reset units on the SoC. This could lead to conflicts if support for other reset controllers on the TH1520 is added in the future like AP.
Let's introduce a new compatible string, "thead,th1520-reset-vo", to explicitly scope the controller to VO-subsystem. The old one is marked as deprecated.
Fixes: 30e7573babdc ("dt-bindings: reset: Add T-HEAD TH1520 SoC Reset Controller") Cc: stable@vger.kernel.org Reported-by: Icenowy Zheng uwu@icenowy.me Co-developed-by: Michal Wilczynski m.wilczynski@samsung.com Signed-off-by: Michal Wilczynski m.wilczynski@samsung.com Signed-off-by: Yao Zi ziyao@disroot.org --- .../bindings/reset/thead,th1520-reset.yaml | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml b/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml index f2e91d0add7a..3930475dcc04 100644 --- a/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml +++ b/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml @@ -15,8 +15,11 @@ maintainers:
properties: compatible: - enum: - - thead,th1520-reset + oneOf: + - enum: + - thead,th1520-reset-vo + - const: thead,th1520-reset + deprecated: true
reg: maxItems: 1 @@ -33,12 +36,8 @@ additionalProperties: false
examples: - | - soc { - #address-cells = <2>; - #size-cells = <2>; - rst: reset-controller@ffef528000 { - compatible = "thead,th1520-reset"; - reg = <0xff 0xef528000 0x0 0x1000>; + reset-controller@ffef528000 { + compatible = "thead,th1520-reset-vo"; + reg = <0xef528000 0x1000>; #reset-cells = <1>; - }; };
On Wed, Aug 20, 2025 at 07:42:43AM +0000, Yao Zi wrote:
The reset controller driver for the TH1520 was using the generic compatible string "thead,th1520-reset". However, the controller described by this compatible only manages the resets for the Video Output (VO) subsystem.
Please use subject prefixes matching the subsystem. You can get them for example with 'git log --oneline -- DIRECTORY_OR_FILE' on the directory your patch is touching. For bindings, the preferred subjects are explained here: https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patche...
Using a generic compatible is confusing as it implies control over all reset units on the SoC. This could lead to conflicts if support for
No, it won't lead to conflicts. Stop making up reasons.
other reset controllers on the TH1520 is added in the future like AP.
Let's introduce a new compatible string, "thead,th1520-reset-vo", to explicitly scope the controller to VO-subsystem. The old one is marked as deprecated.
Fixes: 30e7573babdc ("dt-bindings: reset: Add T-HEAD TH1520 SoC Reset Controller") Cc: stable@vger.kernel.org
Especially for backporting... Describe the actual bug being fixed here.
Reported-by: Icenowy Zheng uwu@icenowy.me Co-developed-by: Michal Wilczynski m.wilczynski@samsung.com Signed-off-by: Michal Wilczynski m.wilczynski@samsung.com Signed-off-by: Yao Zi ziyao@disroot.org
.../bindings/reset/thead,th1520-reset.yaml | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml b/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml index f2e91d0add7a..3930475dcc04 100644 --- a/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml +++ b/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml @@ -15,8 +15,11 @@ maintainers: properties: compatible:
- enum:
- thead,th1520-reset
- oneOf:
- enum:- thead,th1520-reset-vo- const: thead,th1520-resetdeprecated: true
This you can do, but none of this is getting to backports and your DTS is a NAK. This basically means that this is kind of pointless.
Compatibles do not have particular meanings, so entire explanation that it implies something is not true. We have been here, this was discussed for other SoCs and you were told in v1 - don't do that.
You are stuck with the old compatible. Is here an issue to fix? No.
Best regards, Krzysztof
On Thu, Aug 21, 2025 at 09:54:08AM +0200, Krzysztof Kozlowski wrote:
On Wed, Aug 20, 2025 at 07:42:43AM +0000, Yao Zi wrote:
The reset controller driver for the TH1520 was using the generic compatible string "thead,th1520-reset". However, the controller described by this compatible only manages the resets for the Video Output (VO) subsystem.
Please use subject prefixes matching the subsystem. You can get them for example with 'git log --oneline -- DIRECTORY_OR_FILE' on the directory your patch is touching. For bindings, the preferred subjects are explained here: https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patche...
Thanks for your review, I appreciate it and will stick to thead,th1520-reset for the VO reset controller.
But I'm not very clear about the subject prefix: I already have a "dt-bindings: reset: " prefix, should I also make the subject more precise, including the exact file changed when changing a binding file?
I've seen commits either with or without the precise name of the changed binding in subjects. For example,
a341bcfbfa7 dt-bindings: reset: add compatible for bcm63xx ephy control
doesn't scope the prefix to brcm,bcm6345-reset.yaml, while
4e55fb7d60e1 dt-bindings: reset: atmel,at91sam9260-reset: add microchip,sama7d65-rstc
does.
Or do I miss other parts in the subject prefix? Thanks for your explanation.
Best regards, Yao Zi
Using a generic compatible is confusing as it implies control over all reset units on the SoC. This could lead to conflicts if support for
No, it won't lead to conflicts. Stop making up reasons.
other reset controllers on the TH1520 is added in the future like AP.
Let's introduce a new compatible string, "thead,th1520-reset-vo", to explicitly scope the controller to VO-subsystem. The old one is marked as deprecated.
Fixes: 30e7573babdc ("dt-bindings: reset: Add T-HEAD TH1520 SoC Reset Controller") Cc: stable@vger.kernel.org
Especially for backporting... Describe the actual bug being fixed here.
Reported-by: Icenowy Zheng uwu@icenowy.me Co-developed-by: Michal Wilczynski m.wilczynski@samsung.com Signed-off-by: Michal Wilczynski m.wilczynski@samsung.com Signed-off-by: Yao Zi ziyao@disroot.org
.../bindings/reset/thead,th1520-reset.yaml | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-)
diff --git a/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml b/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml index f2e91d0add7a..3930475dcc04 100644 --- a/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml +++ b/Documentation/devicetree/bindings/reset/thead,th1520-reset.yaml @@ -15,8 +15,11 @@ maintainers: properties: compatible:
- enum:
- thead,th1520-reset
- oneOf:
- enum:- thead,th1520-reset-vo- const: thead,th1520-resetdeprecated: trueThis you can do, but none of this is getting to backports and your DTS is a NAK. This basically means that this is kind of pointless.
Compatibles do not have particular meanings, so entire explanation that it implies something is not true. We have been here, this was discussed for other SoCs and you were told in v1 - don't do that.
You are stuck with the old compatible. Is here an issue to fix? No.
Best regards, Krzysztof
On 22/08/2025 10:28, Yao Zi wrote:
On Thu, Aug 21, 2025 at 09:54:08AM +0200, Krzysztof Kozlowski wrote:
On Wed, Aug 20, 2025 at 07:42:43AM +0000, Yao Zi wrote:
The reset controller driver for the TH1520 was using the generic compatible string "thead,th1520-reset". However, the controller described by this compatible only manages the resets for the Video Output (VO) subsystem.
Please use subject prefixes matching the subsystem. You can get them for example with 'git log --oneline -- DIRECTORY_OR_FILE' on the directory your patch is touching. For bindings, the preferred subjects are explained here: https://www.kernel.org/doc/html/latest/devicetree/bindings/submitting-patche...
Thanks for your review, I appreciate it and will stick to thead,th1520-reset for the VO reset controller.
But I'm not very clear about the subject prefix: I already have a "dt-bindings: reset: " prefix, should I also make the subject more precise, including the exact file changed when changing a binding file?
Yes, as you can check in other commits. Your subject claims that you change " Scope the compatible to VO subsystem explicitly" for all reset controllers.
I've seen commits either with or without the precise name of the changed binding in subjects. For example,
a341bcfbfa7 dt-bindings: reset: add compatible for bcm63xx ephy control
But it says bcm63xx at least. Well, you will find plenty of poor examples as well. I gave you template response because you made typical mistake.
Anyway, you ignored rest of my response, so I assume you agree with it completely.
Best regards, Krzysztof
linux-stable-mirror@lists.linaro.org
-
Krzysztof Kozlowski -
Yao Zi