Re: [PATCH v2 2/3] dt-bindings: atmel,hlcdc: convert pwm bindings to json-schema

[Dharma.B]

On 17/01/24 1:40 am, Alexandre Belloni wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On 16/01/2024 18:03:19+0000, Conor Dooley wrote:
>> On Tue, Jan 16, 2024 at 05:07:59PM +0530, Dharma Balasubiramani wrote:
>>> Convert device tree bindings for Atmel's HLCDC PWM controller to YAML
>>> format.
>>>
>>> Signed-off-by: Dharma Balasubiramani <dharma.b@xxxxxxxxxxxxx>
>>> ---
>>> changelog
>>> v1 -> v2
>>> - Remove the explicit copyrights.
>>> - Modify title (not include words like binding/driver).
>>> - Modify description actually describing the hardware and not the driver.
>>> - Remove pinctrl properties which aren't required.
>>> - Drop parent node and it's other sub-device node which are not related here.
>>> ---
>>>   .../bindings/pwm/atmel,hlcdc-pwm.yaml         | 47 +++++++++++++++++++
>>>   .../bindings/pwm/atmel-hlcdc-pwm.txt          | 29 ------------
>>>   2 files changed, 47 insertions(+), 29 deletions(-)
>>>   create mode 100644 Documentation/devicetree/bindings/pwm/atmel,hlcdc-pwm.yaml
>>>   delete mode 100644 Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt
>>>
>>> diff --git a/Documentation/devicetree/bindings/pwm/atmel,hlcdc-pwm.yaml b/Documentation/devicetree/bindings/pwm/atmel,hlcdc-pwm.yaml
>>> new file mode 100644
>>> index 000000000000..751122309fa9
>>> --- /dev/null
>>> +++ b/Documentation/devicetree/bindings/pwm/atmel,hlcdc-pwm.yaml
>>> @@ -0,0 +1,47 @@
>>> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
>>
>> The original file has no license, but was originally written by a
>> free-electrons employee, so the relicensing here is fine.
>>
> 
> I confirm relicensing is fine, even assigning the copyright to
> Microchip (note that Bootlin is legally the same entity as
> free-electrons)
Thanks Conor and Alexandre.
I will add the copyrights back in v3.
> 
>>> +%YAML 1.2
>>> +---
>>> +$id: http://devicetree.org/schemas/pwm/atmel,hlcdc-pwm.yaml#
>>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>>> +
>>> +title: Atmel's HLCDC's PWM controller
>>> +
>>> +maintainers:
>>> +  - Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
>>> +  - Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
>>> +  - Claudiu Beznea <claudiu.beznea@xxxxxxxxx>
>>> +
>>> +description: |
>>
>> Again, the | is not needed here.
Sure, I will drop it.
>>
>>> +  The LCDC integrates a Pulse Width Modulation (PWM) Controller. This block
>>> +  generates the LCD contrast control signal (LCD_PWM) that controls the
>>> +  display's contrast by software. LCDC_PWM is an 8-bit PWM signal that can be
>>> +  converted to an analog voltage with a simple passive filter. LCD display
>>> +  panels have different backlight specifications in terms of minimum/maximum
>>> +  values for PWM frequency. If the LCDC PWM frequency range does not match the
>>> +  LCD display panel, it is possible to use the standalone PWM Controller to
>>> +  drive the backlight.
>>> +
>>> +properties:
>>> +  compatible:
>>> +    const: atmel,hlcdc-pwm
>>> +
>>> +  "#pwm-cells":
>>> +    const: 3
>>> +    description: |
>>> +      This PWM chip uses the default 3 cells bindings defined in pwm.yaml in
>>> +      this directory.
>>
>> I would delete this description tbh.
Sure, I will remove it.
>>
>>> +
>>> +required:
>>> +  - compatible
>>> +  - "#pwm-cells"
>>> +
>>> +additionalProperties: false
>>> +
>>> +examples:
>>> +  - |
>>> +    pwm: pwm {
>>> +      compatible = "atmel,hlcdc-pwm";
>>> +      pinctrl-names = "default";
>>> +      pinctrl-0 = <&pinctrl_lcd_pwm>;
>>> +      #pwm-cells = <3>;
>>> +    };
>>
>> The label here is not used and can be dropped. Otherwise,
>> Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Sure, I will remove the label.

-- 
With Best Regards,
Dharma B.
>>
>>
>> Cheers,
>> Conor.
>>
>>> diff --git a/Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt b/Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt
>>> deleted file mode 100644
>>> index afa501bf7f94..000000000000
>>> --- a/Documentation/devicetree/bindings/pwm/atmel-hlcdc-pwm.txt
>>> +++ /dev/null
>>> @@ -1,29 +0,0 @@
>>> -Device-Tree bindings for Atmel's HLCDC (High-end LCD Controller) PWM driver
>>> -
>>> -The Atmel HLCDC PWM is subdevice of the HLCDC MFD device.
>>> -See ../mfd/atmel-hlcdc.txt for more details.
>>> -
>>> -Required properties:
>>> - - compatible: value should be one of the following:
>>> -   "atmel,hlcdc-pwm"
>>> - - pinctr-names: the pin control state names. Should contain "default".
>>> - - pinctrl-0: should contain the pinctrl states described by pinctrl
>>> -   default.
>>> - - #pwm-cells: should be set to 3. This PWM chip use the default 3 cells
>>> -   bindings defined in pwm.yaml in this directory.
>>> -
>>> -Example:
>>> -
>>> -   hlcdc: hlcdc@f0030000 {
>>> -           compatible = "atmel,sama5d3-hlcdc";
>>> -           reg = <0xf0030000 0x2000>;
>>> -           clocks = <&lcdc_clk>, <&lcdck>, <&clk32k>;
>>> -           clock-names = "periph_clk","sys_clk", "slow_clk";
>>> -
>>> -           hlcdc_pwm: hlcdc-pwm {
>>> -                   compatible = "atmel,hlcdc-pwm";
>>> -                   pinctrl-names = "default";
>>> -                   pinctrl-0 = <&pinctrl_lcd_pwm>;
>>> -                   #pwm-cells = <3>;
>>> -           };
>>> -   };
>>> --
>>> 2.25.1
>>>
> 
> 
> 
> --
> Alexandre Belloni, co-owner and COO, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com