Re: [PATCH v2] dt-bindings: gpu: Convert Samsung Image Scaler to dt-schema

[Maciej Falkowski]

On 9/26/19 4:03 PM, Krzysztof Kozlowski wrote:
> On Thu, Sep 26, 2019 at 02:56:14PM +0200, Marek Szyprowski wrote:
>> From: Maciej Falkowski <m.falkowski@xxxxxxxxxxx>
>>
>> Convert Samsung Image Scaler to newer dt-schema format.
>>
>> Signed-off-by: Maciej Falkowski <m.falkowski@xxxxxxxxxxx>
>> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
>> ---
>> v2:
>> - Removed quotation marks from string in 'compatible' property
>> - Added if-then statement for 'clocks' and 'clock-names' property
>> - Added include directive to example
>> - Added GIC_SPI macro to example
>>
>> Best regards,
>> Maciej Falkowski
>> ---
>>   .../bindings/gpu/samsung-scaler.txt           | 27 -------
>>   .../bindings/gpu/samsung-scaler.yaml          | 71 +++++++++++++++++++
>>   2 files changed, 71 insertions(+), 27 deletions(-)
>>   delete mode 100644 Documentation/devicetree/bindings/gpu/samsung-scaler.txt
>>   create mode 100644 Documentation/devicetree/bindings/gpu/samsung-scaler.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/gpu/samsung-scaler.txt b/Documentation/devicetree/bindings/gpu/samsung-scaler.txt
>> deleted file mode 100644
>> index 9c3d98105dfd..000000000000
>> --- a/Documentation/devicetree/bindings/gpu/samsung-scaler.txt
>> +++ /dev/null
>> @@ -1,27 +0,0 @@
>> -* Samsung Exynos Image Scaler
>> -
>> -Required properties:
>> -  - compatible : value should be one of the following:
>> -	(a) "samsung,exynos5420-scaler" for Scaler IP in Exynos5420
>> -	(b) "samsung,exynos5433-scaler" for Scaler IP in Exynos5433
>> -
>> -  - reg : Physical base address of the IP registers and length of memory
>> -	  mapped region.
>> -
>> -  - interrupts : Interrupt specifier for scaler interrupt, according to format
>> -		 specific to interrupt parent.
>> -
>> -  - clocks : Clock specifier for scaler clock, according to generic clock
>> -	     bindings. (See Documentation/devicetree/bindings/clock/exynos*.txt)
>> -
>> -  - clock-names : Names of clocks. For exynos scaler, it should be "mscl"
>> -		  on 5420 and "pclk", "aclk" and "aclk_xiu" on 5433.
>> -
>> -Example:
>> -	scaler@12800000 {
>> -		compatible = "samsung,exynos5420-scaler";
>> -		reg = <0x12800000 0x1294>;
>> -		interrupts = <0 220 IRQ_TYPE_LEVEL_HIGH>;
>> -		clocks = <&clock CLK_MSCL0>;
>> -		clock-names = "mscl";
>> -	};
>> diff --git a/Documentation/devicetree/bindings/gpu/samsung-scaler.yaml b/Documentation/devicetree/bindings/gpu/samsung-scaler.yaml
>> new file mode 100644
>> index 000000000000..af19930d052e
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/gpu/samsung-scaler.yaml
>> @@ -0,0 +1,71 @@
>> +# SPDX-License-Identifier: GPL-2.0
>> +%YAML 1.2
>> +---
>> +$id: https://protect2.fireeye.com/url?k=1ffa720fd467d028.1ffbf940-9a5a550397b4da2b&u=http://devicetree.org/schemas/gpu/samsung-scaler.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Samsung Exynos SoC Image Scaler
>> +
>> +maintainers:
>> +  - Inki Dae <inki.dae@xxxxxxxxxxx>
>> +
>> +properties:
>> +  compatible:
>> +    enum:
>> +      - samsung,exynos5420-scaler
>> +      - samsung,exynos5433-scaler
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  interrupts:
>> +    maxItems: 1
>> +

Hi Krzysztof,

By "Midgard" I assume that you referred to 
'Documentation/devicetree/bindings/gpu/arm,mali-midgard.yaml'.

I think that 'clocks' and 'clock-names' properties before if statement 
serve different purpose in this schema.
It totally has about 10 different compatibles grouped in five pairs.
Then schema declares for 'clocks' minItems as one and maxItems as two and
later it overrides this boundaries with if statement for particular 
compatibles.
Well, then clearly, the purpose is to declare boundaries for all of 
pairs and
not to provide easy-to-find definition for this properties.

In my schema I directly set boundaries per compatible with single 
if-else statement.
I didn't know what to put before then as if statement is already 
self-explanatory.

Best regards,
Maciej Falkowski

> I am repeating myself... leave the clocks and clock-names.
>
> "I think it is worth to leave the clocks and clock-names here (could be
> empty or with min/max values for number of items). This makes it easy to
> find the properties by humans.
>
> Midgard bindings could be used as example."
>
>> +if:
>> +  properties:
>> +    compatible:
>> +      contains:
>> +        const: samsung,exynos5420-scaler
>> +then:
>> +  properties:
>> +    clocks:
>> +      items:
>> +        - description: mscl clock
>> +
>> +    clock-names:
>> +      items:
>> +        - const: mscl
>> +else:
>> +  properties:
>> +    clocks:
>> +      items:
>> +        - description: mscl clock
>> +        - description: aclk clock
>> +        - description: aclk_xiu clock
>> +
>> +    clock-names:
>> +      items:
>> +        - const: pclk
>> +        - const: aclk
>> +        - const: aclk_xiu
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - interrupts
>> +  - clocks
>> +  - clock-names
>> +
>> +examples:
>> +  - |
>> +    #include <dt-bindings/clock/exynos5420.h>
>> +    #include <dt-bindings/interrupt-controller/arm-gic.h>
>> +
>> +    scaler@12800000 {
>> +        compatible = "samsung,exynos5420-scaler";
>> +        reg = <0x12800000 0x1294>;
>> +        interrupts = <GIC_SPI 220 IRQ_TYPE_LEVEL_HIGH>;
>> +        clocks = <&clock CLK_MSCL0>;
>> +        clock-names = "mscl";
>> +    };
>> +
> Unneeded trailing line.
>
> Best regards,
> Krzysztof
>
>
>