Re: [PATCH v4 2/2] leds: add LED driver for EL15203000 board

Oleh Kravchenko
2019-08-13T20:37:32Z

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Hello Jacek,

Thank you for your useful review,

13.08.19 23:28, Jacek Anaszewski пише:
> Hi Oleh,
>
> Thank you for the patch set.
>
> On 8/8/19 10:32 PM, Oleh Kravchenko wrote:
>> +++ b/Documentation/ABI/testing/sysfs-class-led-driver-el15203000
>> @@ -0,0 +1,22 @@
>> +What: /sys/class/leds/<led>/hw_pattern
>> +Date: August 2019
>> +KernelVersion: 5.3
>> +Description:
>> + Specify a hardware pattern for the EL15203000 LED.
>> + The LEDs board supports only predefined patterns by firmware
>> + for specific LEDs.
>> +
>> + Breathing mode for Screen frame light tube:
>> + "0 4000 1 4000"
>> +
>> + Cascade mode for Pipe LED:
>> + "1 800 2 800 4 800 8 800 16 800 1 800 2 800 4 800 8 800 16 800"
>
> Why the sequence "1 800 2 800 4 800 8 800 16 800" is duplicated here?
> It seems redundant. But aside of that - aren't the timings modifiable?
> In other words - are these all patterns somehow configurable or they are
> pre-programmed?
>

All pattern is predefined, you can't change them at all.
I just tried to describe real things what happened in LED board.
It's ticks every 800 milliseconds for Pipe LEDs.

>> +
>> + Inverted cascade mode for Pipe LED:
>> + "30 800 29 800 27 800 23 800 15 800 30 800 29 800 27 800 23 800 15 800"
>
> Similar duplication here.
>
>> +
>> + Bounce mode for Pipe LED:
>> + "1 800 2 800 4 800 8 800 16 800 16 800 8 800 4 800 2 800 1 800"
>
> Instead of two repeating "16 800" you could provide "16 1600".
> But here again is the question whether these values are configurable.
> From what I can see in your driver implementation you're expecting
> exactly the values provided in these examples to enable given hardware
> pattern (led_pattern_cmp()).
>
>> +
>> + Inverted bounce mode for Pipe LED:
>> + "30 800 29 800 27 800 23 800 15 800 15 800 23 800 27 800 29 800 30 800"
>

Should I cut this patterns to smaller? Or let keep it?

--
Best regards,
Oleh Kravchenko

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