linux-kernel - Re: [PATCH v8 0/5] auxdisplay: add support for TI LP5812 4x3 Matrix LED driver

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Message-Id: <20250512173800.6767-1-trannamatk@gmail.com>
Date: Tue, 13 May 2025 00:38:00 +0700
From: Nam Tran <trannamatk@...il.com>
To: andy@...nel.org
Cc: lee@...nel.org,
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Subject: Re: [PATCH v8 0/5] auxdisplay: add support for TI LP5812 4x3 Matrix LED driver

On Mon, 12 May 2025 Andy Shevchenko wrote:

> On Sat, May 10, 2025 at 02:48:02PM +0700, Nam Tran wrote:
> > On Thu, 8 May 2025 Lee Jones wrote:
> > > On Thu, 08 May 2025, Andy Shevchenko wrote:
> > > > On Thu, May 8, 2025 at 5:27 PM Nam Tran <trannamatk@...il.com> wrote:
> > > > > On Thu, 8 May 2025 Lee Jones wrote:
> > > > > > On Thu, 08 May 2025, Andy Shevchenko wrote:

...

> > I think setting PWM also same as brightness_set API. However, there are
> > many PWM config for a LED and it is one of other config to make autonomous mode work.
> > Therefore, standard led API can use in some use cases only.
> > 
> > Please see the link below for a better visualization of how to configure the LP5812.
> > https://dev.ti.com/gallery/view/LED/LP581x/ver/0.10.0/
> 
> To me it sounds like you should start from the small steps, i.e. do not
> implement everything at once. And starting point of the 4 RGB LEDs sounds
> the best approach to me. Then, if needed, you can always move on with
> fancy features of this hardware on top of the existing code.

Thanks for the suggestion.
I understand your point and agree that starting with standard LED APIs is the preferred approach.

However, the LP5812 hardware offers more advanced features, and I’d like to support end users all
features as shown in the link: https://dev.ti.com/gallery/view/LED/LP581x/ver/0.10.0/.
It is easy for end user to investigate and use driver.

If I want to keep the current driver interface to meet this expectation, would it be acceptable
to move it to the misc subsystem to better support the hardware?

Best regards,
Nam Tran