linux-kernel - Re: [PATCHv1 0/6] leds: pca9653x: support inverted outputs and cleanups

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Date:	Wed, 20 Apr 2016 11:06:42 +0200
From:	Olliver Schinagl <oliver@...inagl.nl>
To:	Ricardo Ribalda Delgado <ricardo.ribalda@...il.com>
Cc:	Jacek Anaszewski <j.anaszewski@...sung.com>,
	Rob Herring <robh+dt@...nel.org>,
	Pawel Moll <pawel.moll@....com>,
	Mark Rutland <mark.rutland@....com>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Kumar Gala <galak@...eaurora.org>,
	Richard Purdie <rpurdie@...ys.net>,
	"devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
	LKML <linux-kernel@...r.kernel.org>,
	Linux LED Subsystem <linux-leds@...r.kernel.org>,
	Peter Meerwald <pmeerw@...erw.net>
Subject: Re: [PATCHv1 0/6] leds: pca9653x: support inverted outputs and
 cleanups



On 20-04-16 10:56, Ricardo Ribalda Delgado wrote:
> Hi
>
> On Wed, Apr 20, 2016 at 10:51 AM, Olliver Schinagl <oliver@...inagl.nl> wrote:
>
>>> As I said before, the reason for this proposal is that the code NEVER
>>> clears PCA963X_MODE2_DMBLNK, only sets it.
>>> Unfortunately I do not have the HW to test this change.
>> The code never clears it, but the hardware does. So we have to set it
>> everytime we enable blink.
> Ok, that was the part I was missing. I was not aware that the hw was
> clearing it.
The devil is in the details :)
> Saving mode2 sounds like a good compromise then.
>
> But I still believe that we should limit the lock to ledout. No matter
> what we do, we cannot have two leds blinking at different frequencies
> on the same chip.
So to save a mutex a little bit, we take the risk that nobody else 
enables the blink or if they do, enable it in the same way?
If it saves so much, then I guess its worth the risk I suppose?
>
>
> Regards
>