Re: [PATCH] leds: pca9532: Extend pca9532 device tree support

From: Jacek Anaszewski <jacek.anaszewski@gmail.com>
To: Felix Brack <fb@ltec.ch>,
	riku.voipio@iki.fi, rpurdie@rpsys.net, pavel@ucw.cz,
	linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: f.brack@eets.ch
Subject: Re: [PATCH] leds: pca9532: Extend pca9532 device tree support
Date: Wed, 29 Mar 2017 20:29:15 +0200	[thread overview]
Message-ID: <203b1577-b6d9-a3a6-4a7c-a9dac9325863@gmail.com> (raw)
In-Reply-To: <e4b6f127-5e5a-04c4-a87f-f6ceeba82a23@ltec.ch>

Hi Felix,

On 03/29/2017 04:26 PM, Felix Brack wrote:
> Hello Jacek,
> 
> On 08.02.2017 20:42, Jacek Anaszewski wrote:
>> Hi Felix,
>>
>> On 02/08/2017 05:12 PM, Felix Brack wrote:
>>> Hello Jacek,
>>>
>>> On 07.02.2017 21:45, Jacek Anaszewski wrote:
>>>> Hi Felix,
>>>>
>>>> Thanks for the patch.
>>>>
>>>> On 02/07/2017 07:11 PM, Felix Brack wrote:
>>>>> This patch extends the device tree support for the pca9532 allowing LEDs to blink, dim or even being unchanged, i.e. not being turned off during driver initialization.
>>>>
>>>> Isn't it possible to apply desired settings with existing LED subsystem
>>>> brightness file, and delay_on/off files exposed by timer trigger?
>>>>
>>>> Best regards,
>>>> Jacek Anaszewski
>>>>
>>>
>>> This might be a misunderstanding. My patch is not meant to replace
>>> anything for driving the LEDs once the kernel is fully loaded. The LED
>>> subsystem offers quite a lot of possibilities to do this.
>>>
>>> My patch mainly deals with the 'default' state of the LEDs immediately
>>> when the driver gets loaded.
>>> Here is an example: I have a system with a LED named 'RUN' which is
>>> turned on steady by U-Boot (indicating "system booting"). When the
>>> PCA9532 driver loads this LED gets turned off due to initialization.
>>> However I would like it remain lit until later a script will make that
>>> 'RUN' LED blink (indicating "system running"). This script will of
>>> course use the existing LED subsystem to do so. To keep the 'RUN' LED
>>> lit I need the DT property 'default-state' being set to 'PCA9532_KEEP'.
>>
>> It looks like all you need is default-state property.
>> I'd rather avoid exposing prescaler and pwm registers in DT.
>>
> 
> For the time being there seems to be no generic timer configuration by
> means of the DT. I have therefore decided to remove the code dealing
> with prescaler and pwm from my patch. This will prevent those registers
> from being exposed to the DT. What will remain is the default-state.
> 
> Should I send an updated version (v2) of this patch or would it be
> better to send a 'new' patch?

Please use current patch title and add v2 to the [PATCH] tag.

-- 
Best regards,
Jacek Anaszewski