2019-09-23 09:04:20

by Dan Murphy

[permalink] [raw]
Subject: [PATCH v8 1/9] leds: multicolor: Add sysfs interface definition

Add a documentation of LED Multicolor LED class specific
sysfs attributes.

Signed-off-by: Dan Murphy <[email protected]>
---
.../ABI/testing/sysfs-class-led-multicolor | 43 +++++++++++++++++++
1 file changed, 43 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-class-led-multicolor

diff --git a/Documentation/ABI/testing/sysfs-class-led-multicolor b/Documentation/ABI/testing/sysfs-class-led-multicolor
new file mode 100644
index 000000000000..39fc73becfec
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-led-multicolor
@@ -0,0 +1,43 @@
+What: /sys/class/leds/<led>/brightness
+Date: Sept 2019
+KernelVersion: 5.5
+Contact: Dan Murphy <[email protected]>
+Description: read/write
+ Writing to this file will update all LEDs within the group to a
+ calculated percentage of what each color LED intensity is set
+ to. The percentage is calculated via the equation below:
+
+ led_brightness = requested_value * led_color_intensity/led_color_max_intensity
+
+ For additional details please refer to
+ Documentation/leds/leds-class-multicolor.rst.
+
+ The value of the color is from 0 to
+ /sys/class/leds/<led>/max_brightness.
+
+What: /sys/class/leds/<led>/colors/<led_color>_intensity
+Date: Sept 2019
+KernelVersion: 5.5
+Contact: Dan Murphy <[email protected]>
+Description: read/write
+ The led_color directory is dynamically created based on the
+ colors defined by the registrar of the class.
+ The value for the led_color is defined in the
+ include/dt-bindings/leds/common.h. There is one directory per
+ color presented. The intensity file is created under each
+ led_color directory and controls the individual LED color
+ setting.
+
+ The value of the color is from 0 to
+ /sys/class/leds/<led>/colors/<led_color>_max_intensity.
+
+What: /sys/class/leds/<led>/colors/<led_color>_max_intensity
+Date: Sept 2019
+KernelVersion: 5.5
+Contact: Dan Murphy <[email protected]>
+Description: read only
+ Maximum intensity level for the LED color, default is
+ 255 (LED_FULL).
+
+ If the LED does not support different intensity levels, this
+ should be 1.
--
2.22.0.214.g8dca754b1e


2019-09-23 17:35:34

by Jacek Anaszewski

[permalink] [raw]
Subject: Re: [PATCH v8 1/9] leds: multicolor: Add sysfs interface definition

Dan,

On 9/20/19 7:41 PM, Dan Murphy wrote:
> Add a documentation of LED Multicolor LED class specific
> sysfs attributes.
>
> Signed-off-by: Dan Murphy <[email protected]>
> ---
> .../ABI/testing/sysfs-class-led-multicolor | 43 +++++++++++++++++++
> 1 file changed, 43 insertions(+)
> create mode 100644 Documentation/ABI/testing/sysfs-class-led-multicolor
>
> diff --git a/Documentation/ABI/testing/sysfs-class-led-multicolor b/Documentation/ABI/testing/sysfs-class-led-multicolor
> new file mode 100644
> index 000000000000..39fc73becfec
> --- /dev/null
> +++ b/Documentation/ABI/testing/sysfs-class-led-multicolor
> @@ -0,0 +1,43 @@
> +What: /sys/class/leds/<led>/brightness
> +Date: Sept 2019
> +KernelVersion: 5.5
> +Contact: Dan Murphy <[email protected]>
> +Description: read/write
> + Writing to this file will update all LEDs within the group to a
> + calculated percentage of what each color LED intensity is set
> + to. The percentage is calculated via the equation below:
> +
> + led_brightness = requested_value * led_color_intensity/led_color_max_intensity

How about:

led_brightness = brightness * <color>_intensity/<color>_max_intensity

> +
> + For additional details please refer to
> + Documentation/leds/leds-class-multicolor.rst.
> +
> + The value of the color is from 0 to
> + /sys/class/leds/<led>/max_brightness.
> +
> +What: /sys/class/leds/<led>/colors/<led_color>_intensity

s/led_color/color/

> +Date: Sept 2019
> +KernelVersion: 5.5
> +Contact: Dan Murphy <[email protected]>
> +Description: read/write
> + The led_color directory is dynamically created based on the
> + colors defined by the registrar of the class.
> + The value for the led_color is defined in the
> + include/dt-bindings/leds/common.h. There is one directory per
> + color presented. The intensity file is created under each
> + led_color directory and controls the individual LED color
> + setting.

We no longer have led_color directories so this description needs
to be adjusted.

And I'd not mention where the colors are defined. This is documentation
for the user, who does not need to know about implementation details.

> +
> + The value of the color is from 0 to
> + /sys/class/leds/<led>/colors/<led_color>_max_intensity.
> +
> +What: /sys/class/leds/<led>/colors/<led_color>_max_intensity
> +Date: Sept 2019
> +KernelVersion: 5.5
> +Contact: Dan Murphy <[email protected]>
> +Description: read only
> + Maximum intensity level for the LED color, default is
> + 255 (LED_FULL).

Mentioning the default value here is pointless IMO. Userspace cannot
change it anyway.

> +
> + If the LED does not support different intensity levels, this
> + should be 1.
>

This is less relevant for MC class, and also it is rather obvious.
I'd skip this sentence.

--
Best regards,
Jacek Anaszewski

2019-09-25 14:37:47

by Dan Murphy

[permalink] [raw]
Subject: Re: [PATCH v8 1/9] leds: multicolor: Add sysfs interface definition

Jacek

Thanks for the review

On 9/21/19 5:55 AM, Jacek Anaszewski wrote:
> Dan,
>
> On 9/20/19 7:41 PM, Dan Murphy wrote:
>> Add a documentation of LED Multicolor LED class specific
>> sysfs attributes.
>>
>> Signed-off-by: Dan Murphy <[email protected]>
>> ---
>> .../ABI/testing/sysfs-class-led-multicolor | 43 +++++++++++++++++++
>> 1 file changed, 43 insertions(+)
>> create mode 100644 Documentation/ABI/testing/sysfs-class-led-multicolor
>>
>> diff --git a/Documentation/ABI/testing/sysfs-class-led-multicolor b/Documentation/ABI/testing/sysfs-class-led-multicolor
>> new file mode 100644
>> index 000000000000..39fc73becfec
>> --- /dev/null
>> +++ b/Documentation/ABI/testing/sysfs-class-led-multicolor
>> @@ -0,0 +1,43 @@
>> +What: /sys/class/leds/<led>/brightness
>> +Date: Sept 2019
>> +KernelVersion: 5.5
>> +Contact: Dan Murphy <[email protected]>
>> +Description: read/write
>> + Writing to this file will update all LEDs within the group to a
>> + calculated percentage of what each color LED intensity is set
>> + to. The percentage is calculated via the equation below:
>> +
>> + led_brightness = requested_value * led_color_intensity/led_color_max_intensity
> How about:
>
> led_brightness = brightness * <color>_intensity/<color>_max_intensity

Ack


>> +
>> + For additional details please refer to
>> + Documentation/leds/leds-class-multicolor.rst.
>> +
>> + The value of the color is from 0 to
>> + /sys/class/leds/<led>/max_brightness.
>> +
>> +What: /sys/class/leds/<led>/colors/<led_color>_intensity
> s/led_color/color/

Ack


>> +Date: Sept 2019
>> +KernelVersion: 5.5
>> +Contact: Dan Murphy <[email protected]>
>> +Description: read/write
>> + The led_color directory is dynamically created based on the
>> + colors defined by the registrar of the class.
>> + The value for the led_color is defined in the
>> + include/dt-bindings/leds/common.h. There is one directory per
>> + color presented. The intensity file is created under each
>> + led_color directory and controls the individual LED color
>> + setting.
> We no longer have led_color directories so this description needs
> to be adjusted.
>
> And I'd not mention where the colors are defined. This is documentation
> for the user, who does not need to know about implementation details.

I thought I updated this but I will re-write this

Ack


>> +
>> + The value of the color is from 0 to
>> + /sys/class/leds/<led>/colors/<led_color>_max_intensity.
>> +
>> +What: /sys/class/leds/<led>/colors/<led_color>_max_intensity
>> +Date: Sept 2019
>> +KernelVersion: 5.5
>> +Contact: Dan Murphy <[email protected]>
>> +Description: read only
>> + Maximum intensity level for the LED color, default is
>> + 255 (LED_FULL).
> Mentioning the default value here is pointless IMO. Userspace cannot
> change it anyway.
>
Ack


>> +
>> + If the LED does not support different intensity levels, this
>> + should be 1.
>>
> This is less relevant for MC class, and also it is rather obvious.
> I'd skip this sentence.
>
Ack


Dan