2023-10-25 18:58:09

by FLAVIO SULIGOI

[permalink] [raw]
Subject: [PATCH v2 0/1] dt-bindings: backlight: mp3309c: remove two required properties

This patch remove the following two not-required properties from the
"required" section:

- max-brightness
- default brightness

These properties are not really required, so they can be removed from the
"required" section.
The "max-brightness" is no longer used in the current version
of the driver (it was used only in the first version).
The "default-brightness", if omitted in the DT, is managed by the
device driver, using a default value. This value depends on the dimming
mode used:

- for the "analog mode", via I2C commands, this value is fixed by
hardware (=31);
- while in case of pwm mode the default used is the last value of the
brightness-levels array.

Also the brightness-levels array is not required:

- in "analog mode", via I2C commands, the brightness-level array is
fixed by hardware (0..31);
- in pwm dimming mode, the driver uses a default array of 0..255 and
the "default-brightness" is the last one, which is "255".

NOTE: there are no compatibility problems with the previous version,
since the device driver has not yet been included in any kernel.
Only this dt-binding yaml file is already included in the
"for-backlight-next" branch of the "backlight" kernel repository.
No developer may have used it.

Other changes:

- improve the backlight working mode descripion in the "description"
section
- update the example, removing the "max-brightness" and introducing the
"brightess-levels" property

NOTE: the "brightess-levels" property is present in the last version of the
common.yaml file, so it is not decalared here.
For this last version of common.yaml file, see my patch:

[1/1] dt-bindings: backlight: add brightness-levels related common
properties
commit: d5272d39995f4150062a67e6f2cef556edece740

Flavio Suligoi (1):
dt-bindings: backlight: mp3309c: remove two required properties

.../bindings/leds/backlight/mps,mp3309c.yaml | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

--
2.34.1


2023-10-26 04:17:13

by FLAVIO SULIGOI

[permalink] [raw]
Subject: [PATCH v2 1/1] dt-bindings: backlight: mp3309c: remove two required properties

The two properties:

- max-brightness
- default brightness

are not really required, so they can be removed from the "required"
section.
The "max-brightness" is no longer used in the current version
of the driver (it was used only in the first version).
The "default-brightness", if omitted in the DT, is managed by the
device driver, using a default value. This value depends on the dimming
mode used:

- for the "analog mode", via I2C commands, this value is fixed by
hardware (=31)
- while in case of pwm mode the default used is the last value of the
brightness-levels array.

Also the brightness-levels array is not required:

- in "analog mode", via I2C commands, the brightness-level array is
fixed by hardware (0..31).;
- in pwm dimming mode, the driver uses a default array of 0..255 and
the "default-brightness" is the last one, which is "255"

NOTE: there are no compatibility problems with the previous version,
since the device driver has not yet been included in any kernel.
Only this dt-binding yaml file is already included in the
"for-backlight-next" branch of the "backlight" kernel repository.
No developer may have used it.

Other changes:

- improve the backlight working mode description, in the "description"
section
- update the example, removing the "max-brightness" and introducing the
"brightess-levels" property

Signed-off-by: Flavio Suligoi <[email protected]>
---
.../bindings/leds/backlight/mps,mp3309c.yaml | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml
index 4191e33626f5..527a37368ed7 100644
--- a/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml
+++ b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml
@@ -14,8 +14,8 @@ description: |
programmable switching frequency to optimize efficiency.
It supports two different dimming modes:

- - analog mode, via I2C commands (default)
- - PWM controlled mode.
+ - analog mode, via I2C commands, as default mode (32 dimming levels)
+ - PWM controlled mode (optional)

The datasheet is available at:
https://www.monolithicpower.com/en/mp3309c.html
@@ -50,8 +50,6 @@ properties:
required:
- compatible
- reg
- - max-brightness
- - default-brightness

unevaluatedProperties: false

@@ -66,8 +64,8 @@ examples:
compatible = "mps,mp3309c";
reg = <0x17>;
pwms = <&pwm1 0 3333333 0>; /* 300 Hz --> (1/f) * 1*10^9 */
- max-brightness = <100>;
- default-brightness = <80>;
+ brightness-levels = <0 4 8 16 32 64 128 255>;
+ default-brightness = <6>;
mps,overvoltage-protection-microvolt = <24000000>;
};
};
--
2.34.1

2023-10-26 14:58:05

by Conor Dooley

[permalink] [raw]
Subject: Re: [PATCH v2 1/1] dt-bindings: backlight: mp3309c: remove two required properties

On Wed, Oct 25, 2023 at 05:50:57PM +0200, Flavio Suligoi wrote:
> The two properties:
>
> - max-brightness
> - default brightness
>
> are not really required, so they can be removed from the "required"
> section.
> The "max-brightness" is no longer used in the current version
> of the driver (it was used only in the first version).
> The "default-brightness", if omitted in the DT, is managed by the
> device driver, using a default value. This value depends on the dimming
> mode used:
>
> - for the "analog mode", via I2C commands, this value is fixed by
> hardware (=31)
> - while in case of pwm mode the default used is the last value of the
> brightness-levels array.
>
> Also the brightness-levels array is not required:
>
> - in "analog mode", via I2C commands, the brightness-level array is
> fixed by hardware (0..31).;
> - in pwm dimming mode, the driver uses a default array of 0..255 and
> the "default-brightness" is the last one, which is "255"
>

> NOTE: there are no compatibility problems with the previous version,
> since the device driver has not yet been included in any kernel.
> Only this dt-binding yaml file is already included in the
> "for-backlight-next" branch of the "backlight" kernel repository.
> No developer may have used it.

I'd argue
Fixes: 02c4e661658f ("dt-bindings: backlight: Add MPS MP3309C")
but that's up to Lee.
Acked-by: Conor Dooley <[email protected]>

Thanks,
Conor.

>
> Other changes:
>
> - improve the backlight working mode description, in the "description"
> section
> - update the example, removing the "max-brightness" and introducing the
> "brightess-levels" property
>
> Signed-off-by: Flavio Suligoi <[email protected]>
> ---
> .../bindings/leds/backlight/mps,mp3309c.yaml | 10 ++++------
> 1 file changed, 4 insertions(+), 6 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml
> index 4191e33626f5..527a37368ed7 100644
> --- a/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml
> +++ b/Documentation/devicetree/bindings/leds/backlight/mps,mp3309c.yaml
> @@ -14,8 +14,8 @@ description: |
> programmable switching frequency to optimize efficiency.
> It supports two different dimming modes:
>
> - - analog mode, via I2C commands (default)
> - - PWM controlled mode.
> + - analog mode, via I2C commands, as default mode (32 dimming levels)
> + - PWM controlled mode (optional)
>
> The datasheet is available at:
> https://www.monolithicpower.com/en/mp3309c.html
> @@ -50,8 +50,6 @@ properties:
> required:
> - compatible
> - reg
> - - max-brightness
> - - default-brightness
>
> unevaluatedProperties: false
>
> @@ -66,8 +64,8 @@ examples:
> compatible = "mps,mp3309c";
> reg = <0x17>;
> pwms = <&pwm1 0 3333333 0>; /* 300 Hz --> (1/f) * 1*10^9 */
> - max-brightness = <100>;
> - default-brightness = <80>;
> + brightness-levels = <0 4 8 16 32 64 128 255>;
> + default-brightness = <6>;
> mps,overvoltage-protection-microvolt = <24000000>;
> };
> };
> --
> 2.34.1
>


Attachments:
(No filename) (3.28 kB)
signature.asc (235.00 B)
Download all attachments