mbox series

[v3,0/3] Convert Microchip's HLCDC Text based DT bindings to JSON schema

Message ID 20240118092612.117491-1-dharma.b@microchip.com (mailing list archive)
Headers show
Series Convert Microchip's HLCDC Text based DT bindings to JSON schema | expand

Message

Dharma Balasubiramani Jan. 18, 2024, 9:26 a.m. UTC
Converted the text bindings to YAML and validated them individually using following commands

$ make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
$ make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/

changelogs are available in respective patches.

Dharma Balasubiramani (3):
  dt-bindings: display: convert Atmel's HLCDC to DT schema
  dt-bindings: atmel,hlcdc: convert pwm bindings to json-schema
  dt-bindings: mfd: atmel,hlcdc: Convert to DT schema format

 .../atmel/atmel,hlcdc-display-controller.yaml | 84 ++++++++++++++++
 .../bindings/display/atmel/hlcdc-dc.txt       | 75 --------------
 .../devicetree/bindings/mfd/atmel,hlcdc.yaml  | 97 +++++++++++++++++++
 .../devicetree/bindings/mfd/atmel-hlcdc.txt   | 56 -----------
 .../bindings/pwm/atmel,hlcdc-pwm.yaml         | 44 +++++++++
 .../bindings/pwm/atmel-hlcdc-pwm.txt          | 29 ------
 6 files changed, 225 insertions(+), 160 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/display/atmel/atmel,hlcdc-display-controller.yaml
 delete mode 100644 Documentation/devicetree/bindings/display/atmel/hlcdc-dc.txt
 create mode 100644 Documentation/devicetree/bindings/mfd/atmel,hlcdc.yaml
 delete mode 100644 Documentation/devicetree/bindings/mfd/atmel-hlcdc.txt
 create mode 100644 Documentation/devicetree/bindings/pwm/atmel,hlcdc-pwm.yaml
 delete mode 100644 Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt

Comments

Sam Ravnborg Jan. 18, 2024, 7:30 p.m. UTC | #1
Hi Dharma et al.

On Thu, Jan 18, 2024 at 02:56:09PM +0530, Dharma Balasubiramani wrote:
> Converted the text bindings to YAML and validated them individually using following commands
> 
> $ make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
> $ make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
> 
> changelogs are available in respective patches.
> 
> Dharma Balasubiramani (3):
>   dt-bindings: display: convert Atmel's HLCDC to DT schema
>   dt-bindings: atmel,hlcdc: convert pwm bindings to json-schema
>   dt-bindings: mfd: atmel,hlcdc: Convert to DT schema format

I know this is a bit late to ask - sorry in advance.

The binding describes the single IP block as a multi functional device,
but it is a single IP block that includes the display controller and a
simple pwm that can be used for contrast or backlight.

If we ignore the fact that the current drivers for hlcdc uses an mfd
abstraction, is this then the optimal way to describe the HW?


In one of my stale git tree I converted atmel lcdc to DT, and here
I used:

+  "#pwm-cells":
+    description:
+      This PWM chip use the default 3 cells bindings
+      defined in ../../pwm/pwm.yaml.
+    const: 3
+
+  clocks:
+    maxItems: 2
+
+  clock-names:
+    maxItems: 2
+    items:
+      - const: lcdc_clk
+      - const: hclk

This proved to be a simple way to describe the HW.

To make the DT binding backward compatible you likely need to add a few
compatible that otherwise would have been left out - but that should do
the trick.

The current atmel hlcdc driver that is split in three is IMO an
over-engineering, and the driver could benefit merging it all in one.
And the binding should not prevent this.

	Sam
Dharma Balasubiramani Jan. 19, 2024, 8:41 a.m. UTC | #2
Hi Sam,
On 19/01/24 1:00 am, Sam Ravnborg wrote:
> [You don't often get email from sam@ravnborg.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> 
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> Hi Dharma et al.
> 
> On Thu, Jan 18, 2024 at 02:56:09PM +0530, Dharma Balasubiramani wrote:
>> Converted the text bindings to YAML and validated them individually using following commands
>>
>> $ make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
>> $ make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
>>
>> changelogs are available in respective patches.
>>
>> Dharma Balasubiramani (3):
>>    dt-bindings: display: convert Atmel's HLCDC to DT schema
>>    dt-bindings: atmel,hlcdc: convert pwm bindings to json-schema
>>    dt-bindings: mfd: atmel,hlcdc: Convert to DT schema format
> 
> I know this is a bit late to ask - sorry in advance.
> 
> The binding describes the single IP block as a multi functional device,
> but it is a single IP block that includes the display controller and a
> simple pwm that can be used for contrast or backlight.
yes.
> 
> If we ignore the fact that the current drivers for hlcdc uses an mfd
> abstraction, is this then the optimal way to describe the HW?
> 
> 
> In one of my stale git tree I converted atmel lcdc to DT, and here
Are you referring the "bindings/display/atmel,lcdc.txt"?
> I used:
> 
> +  "#pwm-cells":
> +    description:
> +      This PWM chip use the default 3 cells bindings
> +      defined in ../../pwm/pwm.yaml.
> +    const: 3
> +
> +  clocks:
> +    maxItems: 2
> +
> +  clock-names:
> +    maxItems: 2
> +    items:
> +      - const: lcdc_clk
> +      - const: hclk
> 
> This proved to be a simple way to describe the HW.
> 
> To make the DT binding backward compatible you likely need to add a few
> compatible that otherwise would have been left out - but that should do
> the trick.
again you mean the compatibles from atmel,lcdc binding?
> 
> The current atmel hlcdc driver that is split in three is IMO an
> over-engineering, and the driver could benefit merging it all in one.
> And the binding should not prevent this.
could you please confirm if my understanding is correct: you want a 
unified display binding that encompasses the properties of the two 
subdevices (display controller and pwm), eliminating the need to 
reference them in additional bindings?
> 
>          Sam
Rob Herring Jan. 19, 2024, 7:51 p.m. UTC | #3
On Thu, Jan 18, 2024 at 08:30:40PM +0100, Sam Ravnborg wrote:
> Hi Dharma et al.
> 
> On Thu, Jan 18, 2024 at 02:56:09PM +0530, Dharma Balasubiramani wrote:
> > Converted the text bindings to YAML and validated them individually using following commands
> > 
> > $ make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
> > $ make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
> > 
> > changelogs are available in respective patches.
> > 
> > Dharma Balasubiramani (3):
> >   dt-bindings: display: convert Atmel's HLCDC to DT schema
> >   dt-bindings: atmel,hlcdc: convert pwm bindings to json-schema
> >   dt-bindings: mfd: atmel,hlcdc: Convert to DT schema format
> 
> I know this is a bit late to ask - sorry in advance.
> 
> The binding describes the single IP block as a multi functional device,
> but it is a single IP block that includes the display controller and a
> simple pwm that can be used for contrast or backlight.
> 
> If we ignore the fact that the current drivers for hlcdc uses an mfd
> abstraction, is this then the optimal way to describe the HW?
> 
> 
> In one of my stale git tree I converted atmel lcdc to DT, and here
> I used:
> 
> +  "#pwm-cells":
> +    description:
> +      This PWM chip use the default 3 cells bindings
> +      defined in ../../pwm/pwm.yaml.
> +    const: 3
> +
> +  clocks:
> +    maxItems: 2
> +
> +  clock-names:
> +    maxItems: 2
> +    items:
> +      - const: lcdc_clk
> +      - const: hclk
> 
> This proved to be a simple way to describe the HW.
> 
> To make the DT binding backward compatible you likely need to add a few
> compatible that otherwise would have been left out - but that should do
> the trick.
> 
> The current atmel hlcdc driver that is split in three is IMO an
> over-engineering, and the driver could benefit merging it all in one.
> And the binding should not prevent this.

I agree on all this, but a conversion is not really the time to redesign 
things. Trust me, I've wanted to on lots of conversions. It should be 
possible to simplify the driver side while keeping the DT as-is. Just 
make the display driver bind to the MFD node instead. After that, then 
one could look at flattening everything to 1 node.

Rob
Sam Ravnborg Jan. 19, 2024, 9:33 p.m. UTC | #4
Hi Dharma,

On Fri, Jan 19, 2024 at 08:41:04AM +0000, Dharma.B@microchip.com wrote:
> Hi Sam,
> On 19/01/24 1:00 am, Sam Ravnborg wrote:
> > [You don't often get email from sam@ravnborg.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> > 
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> > 
> > Hi Dharma et al.
> > 
> > On Thu, Jan 18, 2024 at 02:56:09PM +0530, Dharma Balasubiramani wrote:
> >> Converted the text bindings to YAML and validated them individually using following commands
> >>
> >> $ make dt_binding_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
> >> $ make dtbs_check DT_SCHEMA_FILES=Documentation/devicetree/bindings/
> >>
> >> changelogs are available in respective patches.
> >>
> >> Dharma Balasubiramani (3):
> >>    dt-bindings: display: convert Atmel's HLCDC to DT schema
> >>    dt-bindings: atmel,hlcdc: convert pwm bindings to json-schema
> >>    dt-bindings: mfd: atmel,hlcdc: Convert to DT schema format
> > 
> > I know this is a bit late to ask - sorry in advance.
> > 
> > The binding describes the single IP block as a multi functional device,
> > but it is a single IP block that includes the display controller and a
> > simple pwm that can be used for contrast or backlight.
> yes.
> > 
> > If we ignore the fact that the current drivers for hlcdc uses an mfd
> > abstraction, is this then the optimal way to describe the HW?
> > 
> > 
> > In one of my stale git tree I converted atmel lcdc to DT, and here
> Are you referring the "bindings/display/atmel,lcdc.txt"?
Correct.

> > I used:
> > 
> > +  "#pwm-cells":
> > +    description:
> > +      This PWM chip use the default 3 cells bindings
> > +      defined in ../../pwm/pwm.yaml.
> > +    const: 3
> > +
> > +  clocks:
> > +    maxItems: 2
> > +
> > +  clock-names:
> > +    maxItems: 2
> > +    items:
> > +      - const: lcdc_clk
> > +      - const: hclk
> > 
> > This proved to be a simple way to describe the HW.
> > 
> > To make the DT binding backward compatible you likely need to add a few
> > compatible that otherwise would have been left out - but that should do
> > the trick.
> again you mean the compatibles from atmel,lcdc binding?

If the new binding describes the full IP, as I suggest, then I assume
you need to add the compatible "atmel,hlcdc-pwm" to be backward
compatible. Otherwise users assuming the old binding will fail to find
the pwm info. I am not sure how important this is - but at least then
the device trees can be updated out of sync with the current users.

I hope this explains what I tried to say, otherwise do not hesitate to
get back to me.

	Sam
Sam Ravnborg Jan. 20, 2024, 1:23 p.m. UTC | #5
Hi Dharma & Rob.

> > To make the DT binding backward compatible you likely need to add a few
> > compatible that otherwise would have been left out - but that should do
> > the trick.
> > 
> > The current atmel hlcdc driver that is split in three is IMO an
> > over-engineering, and the driver could benefit merging it all in one.
> > And the binding should not prevent this.
> 
> I agree on all this, but a conversion is not really the time to redesign 
> things. Trust me, I've wanted to on lots of conversions. It should be 
> possible to simplify the driver side while keeping the DT as-is. Just 
> make the display driver bind to the MFD node instead. After that, then 
> one could look at flattening everything to 1 node.

Understood and thinking a bit about it fully agreed as well.
Dharma - please see my comments only as ideas for the future, and
ignore them in this fine rewrite you do.

	Sam
Dharma Balasubiramani Jan. 22, 2024, 3:52 a.m. UTC | #6
On 20/01/24 6:53 pm, Sam Ravnborg wrote:
> [You don't often get email from sam@ravnborg.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> 
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> Hi Sam & Rob,
> Hi Dharma & Rob.
> 
>>> To make the DT binding backward compatible you likely need to add a few
>>> compatible that otherwise would have been left out - but that should do
>>> the trick.
>>>
>>> The current atmel hlcdc driver that is split in three is IMO an
>>> over-engineering, and the driver could benefit merging it all in one.
>>> And the binding should not prevent this.
>>
>> I agree on all this, but a conversion is not really the time to redesign
>> things. Trust me, I've wanted to on lots of conversions. It should be
>> possible to simplify the driver side while keeping the DT as-is. Just
>> make the display driver bind to the MFD node instead. After that, then
>> one could look at flattening everything to 1 node.
> 
> Understood and thinking a bit about it fully agreed as well.
> Dharma - please see my comments only as ideas for the future, and
> ignore them in this fine rewrite you do.
> 
>          Sam
Based on your insights, I'm contemplating the decision to merge Patch 2 
[PWM binding] with Patch 3[MFD binding]. It seems redundant given that 
we already have a PWM node example in the MFD binding.

Instead of introducing a new PWM binding,
   pwm:
     $ref: /schemas/pwm/atmel,hlcdc-pwm.yaml

I will update the existing MFD binding as follows:

properties:
   compatible:
     const: atmel,hlcdc-pwm

   "#pwm-cells":
     const: 3

required:
   - compatible
   - "#pwm-cells"
Sam Ravnborg Jan. 22, 2024, 4:02 p.m. UTC | #7
Hi Dharma
On Mon, Jan 22, 2024 at 03:52:17AM +0000, Dharma.B@microchip.com wrote:
> On 20/01/24 6:53 pm, Sam Ravnborg wrote:
> > [You don't often get email from sam@ravnborg.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> > 
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> > Hi Sam & Rob,
> > Hi Dharma & Rob.
> > 
> >>> To make the DT binding backward compatible you likely need to add a few
> >>> compatible that otherwise would have been left out - but that should do
> >>> the trick.
> >>>
> >>> The current atmel hlcdc driver that is split in three is IMO an
> >>> over-engineering, and the driver could benefit merging it all in one.
> >>> And the binding should not prevent this.
> >>
> >> I agree on all this, but a conversion is not really the time to redesign
> >> things. Trust me, I've wanted to on lots of conversions. It should be
> >> possible to simplify the driver side while keeping the DT as-is. Just
> >> make the display driver bind to the MFD node instead. After that, then
> >> one could look at flattening everything to 1 node.
> > 
> > Understood and thinking a bit about it fully agreed as well.
> > Dharma - please see my comments only as ideas for the future, and
> > ignore them in this fine rewrite you do.
> > 
> >          Sam
> Based on your insights, I'm contemplating the decision to merge Patch 2 
> [PWM binding] with Patch 3[MFD binding]. It seems redundant given that 
> we already have a PWM node example in the MFD binding.
> 
> Instead of introducing a new PWM binding,
>    pwm:
>      $ref: /schemas/pwm/atmel,hlcdc-pwm.yaml
> 
> I will update the existing MFD binding as follows:
> 
> properties:
>    compatible:
>      const: atmel,hlcdc-pwm
> 
>    "#pwm-cells":
>      const: 3
> 
> required:
>    - compatible
>    - "#pwm-cells"
> 
Good idea, this looks like a nice simplification.

	Sam
Sam Ravnborg Jan. 22, 2024, 4:04 p.m. UTC | #8
Hi Dharma,
On Mon, Jan 22, 2024 at 03:52:17AM +0000, Dharma.B@microchip.com wrote:
> On 20/01/24 6:53 pm, Sam Ravnborg wrote:
> > [You don't often get email from sam@ravnborg.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> > 
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> > Hi Sam & Rob,
> > Hi Dharma & Rob.
> > 
> >>> To make the DT binding backward compatible you likely need to add a few
> >>> compatible that otherwise would have been left out - but that should do
> >>> the trick.
> >>>
> >>> The current atmel hlcdc driver that is split in three is IMO an
> >>> over-engineering, and the driver could benefit merging it all in one.
> >>> And the binding should not prevent this.
> >>
> >> I agree on all this, but a conversion is not really the time to redesign
> >> things. Trust me, I've wanted to on lots of conversions. It should be
> >> possible to simplify the driver side while keeping the DT as-is. Just
> >> make the display driver bind to the MFD node instead. After that, then
> >> one could look at flattening everything to 1 node.
> > 
> > Understood and thinking a bit about it fully agreed as well.
> > Dharma - please see my comments only as ideas for the future, and
> > ignore them in this fine rewrite you do.
> > 
> >          Sam
> Based on your insights, I'm contemplating the decision to merge Patch 2 
> [PWM binding] with Patch 3[MFD binding]. It seems redundant given that 
> we already have a PWM node example in the MFD binding.
> 
> Instead of introducing a new PWM binding,
>    pwm:
>      $ref: /schemas/pwm/atmel,hlcdc-pwm.yaml
> 
> I will update the existing MFD binding as follows:
> 
> properties:
>    compatible:
>      const: atmel,hlcdc-pwm
> 
>    "#pwm-cells":
>      const: 3
> 
> required:
>    - compatible
>    - "#pwm-cells"
> 
As already commented, this looks nice.
But as Rob said, this should be a 1:1 conversion from text to yaml,
and then clean-up can come in the second step.

	Sam
Dharma Balasubiramani Jan. 24, 2024, 8:55 a.m. UTC | #9
On 22/01/24 9:34 pm, Sam Ravnborg wrote:
> [You don't often get email from sam@ravnborg.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> 
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> Hi Dharma,
> On Mon, Jan 22, 2024 at 03:52:17AM +0000, Dharma.B@microchip.com wrote:
>> On 20/01/24 6:53 pm, Sam Ravnborg wrote:
>>> [You don't often get email from sam@ravnborg.org. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
>>>
>>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>>> Hi Sam & Rob,
>>> Hi Dharma & Rob.
>>>
>>>>> To make the DT binding backward compatible you likely need to add a few
>>>>> compatible that otherwise would have been left out - but that should do
>>>>> the trick.
>>>>>
>>>>> The current atmel hlcdc driver that is split in three is IMO an
>>>>> over-engineering, and the driver could benefit merging it all in one.
>>>>> And the binding should not prevent this.
>>>>
>>>> I agree on all this, but a conversion is not really the time to redesign
>>>> things. Trust me, I've wanted to on lots of conversions. It should be
>>>> possible to simplify the driver side while keeping the DT as-is. Just
>>>> make the display driver bind to the MFD node instead. After that, then
>>>> one could look at flattening everything to 1 node.
>>>
>>> Understood and thinking a bit about it fully agreed as well.
>>> Dharma - please see my comments only as ideas for the future, and
>>> ignore them in this fine rewrite you do.
>>>
>>>           Sam
>> Based on your insights, I'm contemplating the decision to merge Patch 2
>> [PWM binding] with Patch 3[MFD binding]. It seems redundant given that
>> we already have a PWM node example in the MFD binding.
>>
>> Instead of introducing a new PWM binding,
>>     pwm:
>>       $ref: /schemas/pwm/atmel,hlcdc-pwm.yaml
>>
>> I will update the existing MFD binding as follows:
>>
>> properties:
>>     compatible:
>>       const: atmel,hlcdc-pwm
>>
>>     "#pwm-cells":
>>       const: 3
>>
>> required:
>>     - compatible
>>     - "#pwm-cells"
>>
> As already commented, this looks nice.
> But as Rob said, this should be a 1:1 conversion from text to yaml,
> and then clean-up can come in the second step.

Fine, I will send v4 with no changes in [PATCH 2] PWM binding, I will 
send another separate patch for this clean up.