diff mbox series

[1/4] dt-bindings: spi: amlogic,a1-spifc: make power-domains required

Message ID 20240708194808.1819185-2-gnstark@salutedevices.com (mailing list archive)
State New, archived
Headers show
Series amlogic SoC's power-domains fixes | expand

Commit Message

George Stark July 8, 2024, 7:48 p.m. UTC
SPI Flash Controller has dedicated power domain so make the
corresponding property required.

Signed-off-by: George Stark <gnstark@salutedevices.com>
---
 Documentation/devicetree/bindings/spi/amlogic,a1-spifc.yaml | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Krzysztof Kozlowski July 8, 2024, 7:51 p.m. UTC | #1
On 08/07/2024 21:48, George Stark wrote:
> SPI Flash Controller has dedicated power domain so make the
> corresponding property required.

That's an ABI break. Being part of power domain does not necessarily
mean it must be required, so your commit msg lacks rationale. Especially
on the ABI part.



Best regards,
Krzysztof
Rob Herring (Arm) July 8, 2024, 9:48 p.m. UTC | #2
On Mon, 08 Jul 2024 22:48:05 +0300, George Stark wrote:
> SPI Flash Controller has dedicated power domain so make the
> corresponding property required.
> 
> Signed-off-by: George Stark <gnstark@salutedevices.com>
> ---
>  Documentation/devicetree/bindings/spi/amlogic,a1-spifc.yaml | 4 ++++
>  1 file changed, 4 insertions(+)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/spi/amlogic,a1-spifc.example.dtb: spi@fd000400: Unevaluated properties are not allowed ('power-domains' was unexpected)
	from schema $id: http://devicetree.org/schemas/spi/amlogic,a1-spifc.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20240708194808.1819185-2-gnstark@salutedevices.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.
George Stark July 10, 2024, 4:23 p.m. UTC | #3
Hello Krzysztof, Neil, Rob

Thanks for your reviews.

I'd just like to clarify things a little on that matter. On A1 most of
periphery has either dedicated power domain (ir, spifc, spi, cpu etc) or
several peripheries share single PD e.g. pwm, temp sensor, i2c, adc
share PD 12. Appropriate PD must be turned on before the periphery is
touched and be on while periphery is used. Experiments confirm it. So
power-domains property in dts nodes is really required. It makes kernel
to control PDs when bound periphery is used.

If I understand bindings thing correctly we should make power-domains
property required in bindings too in that case, at least for those
peripheries which has *a1* compatibles (some peripheries use compatible
from older SoCs without PDs).

What you think?

On 7/8/24 22:51, Krzysztof Kozlowski wrote:
> On 08/07/2024 21:48, George Stark wrote:
>> SPI Flash Controller has dedicated power domain so make the
>> corresponding property required.
> 
> That's an ABI break. Being part of power domain does not necessarily
> mean it must be required, so your commit msg lacks rationale. Especially
> on the ABI part.
> 
> 
> 
> Best regards,
> Krzysztof
>
Neil Armstrong July 10, 2024, 4:38 p.m. UTC | #4
On 10/07/2024 18:23, George Stark wrote:
> Hello Krzysztof, Neil, Rob
> 
> Thanks for your reviews.
> 
> I'd just like to clarify things a little on that matter. On A1 most of
> periphery has either dedicated power domain (ir, spifc, spi, cpu etc) or
> several peripheries share single PD e.g. pwm, temp sensor, i2c, adc
> share PD 12. Appropriate PD must be turned on before the periphery is
> touched and be on while periphery is used. Experiments confirm it. So
> power-domains property in dts nodes is really required. It makes kernel
> to control PDs when bound periphery is used.
> 
> If I understand bindings thing correctly we should make power-domains
> property required in bindings too in that case, at least for those
> peripheries which has *a1* compatibles (some peripheries use compatible
> from older SoCs without PDs).
> 
> What you think?

Yes, but if the compatible has already been defined without a required
power-domain, then it's too late to mark it as required since it's an ABI
break.

So next time a new compatible is added, it's the appropriate time to mark
it as required.

But in any case it's not a big deal because if the power-domain is not
specified it won't work, like if you use wrong register address or the
wrong interrupt line.

The fact power-domain can be specified is enough.

Neil

> 
> On 7/8/24 22:51, Krzysztof Kozlowski wrote:
>> On 08/07/2024 21:48, George Stark wrote:
>>> SPI Flash Controller has dedicated power domain so make the
>>> corresponding property required.
>>
>> That's an ABI break. Being part of power domain does not necessarily
>> mean it must be required, so your commit msg lacks rationale. Especially
>> on the ABI part.
>>
>>
>>
>> Best regards,
>> Krzysztof
>>
>
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/spi/amlogic,a1-spifc.yaml b/Documentation/devicetree/bindings/spi/amlogic,a1-spifc.yaml
index 043879b434ac..e704aff8a862 100644
--- a/Documentation/devicetree/bindings/spi/amlogic,a1-spifc.yaml
+++ b/Documentation/devicetree/bindings/spi/amlogic,a1-spifc.yaml
@@ -30,15 +30,19 @@  required:
   - compatible
   - reg
   - clocks
+  - power-domains
 
 unevaluatedProperties: false
 
 examples:
   - |
+    #include <dt-bindings/power/meson-a1-power.h>
+
     spi@fd000400 {
         compatible = "amlogic,a1-spifc";
         reg = <0xfd000400 0x290>;
         clocks = <&clkc_clkid_spifc>;
         #address-cells = <1>;
         #size-cells = <0>;
+        power-domains = <&pwrc PWRC_SPIFC_ID>;
     };