[PATCH v3 1/2] leds: mt6360: Add LED driver for MT6360

Jacek Anaszewski jacek.anaszewski at gmail.com
Thu Sep 10 16:31:28 EDT 2020


On 9/10/20 10:25 PM, Pavel Machek wrote:
> Hi!
> 
>>>> 1. set FLED1 brightness
>>>> # echo 1 > /sys/class/leds/white:flash1/flash_brightness
>>>> 2. enable FLED1 strobe
>>>> # echo 1 > /sys/class/leds/white:flash1/flash_strobe
>>>> 3 . turn off FLED1 strobe (just used to gaurantee the strobe mode
>>>> flash leds must be turned off)
>>>> # echo 0 > /sys/class/leds/white:flash1/flash_strobe
>>>
>>> I believe I'd preffer only exposing torch functionality in
>>> /sys/class/leds. .. strobe can be supported using v4l2 APIs.
>>
>> Actually having LED flash class without strobe is pointless.
>> If you looked at led_classdev_flash_register_ext() you would see that
>> it fails with uninitialized strobe_set op. And V4L2 API for strobing
>> flash calls strobe_set from LED flash class beneath.
>>
>> That was the idea behind LED and V4L2 flash API unification - there
>> is one hardware driver needed, the V4L2 Flash layer just takes over
>> control over it when needed.
> 
> I agree that one driver is enough.
> 
> But we should not need flash_strobe file in sysfs. Simply use V4L2 for
> that.

Apart from the fact that we can't remove it from LED flash class ABI
now, why would you like to prevent the user from exploiting main feature
of the hardware?

-- 
Best regards,
Jacek Anaszewski



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