From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stas Sergeev <stsp@list.ru>
Subject: Re: [PATCH v2 0/3] leds: blink resolution improvements
Date: Tue, 28 Apr 2015 01:23:07 +0300
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To: Pavel Machek <pavel@ucw.cz>
Cc: linux-leds@vger.kernel.org, Linux kernel <linux-kernel@vger.kernel.org>, Stas Sergeev <stsp@users.sourceforge.net>

27.04.2015 23:54, Pavel Machek =D0=BF=D0=B8=D1=88=D0=B5=D1=82:
> Hi!
>
>> The following patches improve the precision of led
>> timer trigger and add the delay unit control.
>> That allows to make PWM brightness control with timer
>> trigger.
> Are you sure that is good idea? Doing LED pwm with main cpu is quite =
harsh...
>
> We already have "brightness" for... well... brightness level.
Btw, your concern can also be addressed in a simple way:
just remove the "brightness" attribute in "timer" mode if the
HW does not support brightness. In some modes you still
need brightness to write either 0 or 255, but in timer mode
it seems absolutely redundant without a HW implementation.
I'd like to create the patch to conditionally disable the
brightness attr in "timer" mode, but I wonder if the change
will have the unexpected compatibility problems...