Re: [PATCH v2] pwm-backlight: allow for non-increasing brightnesslevels

From: Jingoo Han
Date: Thu Sep 26 2013 - 23:19:48 EST

On Thursday, September 26, 2013 10:00 PM, Thierry Reding wrote:
> On Thu, Sep 26, 2013 at 03:08:22PM +0300, Tomi Valkeinen wrote:
> > On 26/09/13 14:51, Thierry Reding wrote:
> > > On Thu, Sep 26, 2013 at 01:03:06PM +0300, Tomi Valkeinen wrote:
> > > [...]
> > >> But if you and Thierry think this version is good, I'll take it.
> > >
> > > That sounds like you want to take it through the fbdev tree. Jingoo is
> > > listed (along with Richard, but he hasn't been responsive to email for
> > > years) as maintainer for the backlight subsystem. Furthermore back at
> >
> > Ah, so they are. I just thought it falls under fbdev, as it's under
> > drivers/video/ =).
> >
> > I don't have any particular "want" to take it through fbdev tree. But I
> > can take it.
> >
> > > the time when I began working on the PWM subsystem, the backlight sub-
> > > system was pretty much orphaned, and pwm-backlight was by far the
> > > biggest user of the PWM subsystem. I adopted the driver at the time
> > > because it needed to be updated for PWM subsystem changes.
> > >
> > > What's the plan going forward? Given the coupling between the PWM
> > > subsystem and the pwm-backlight driver it might be useful to keep
> > > maintaining it as part of the PWM subsystem. On the other hand, there's
> > > some coupling between the driver and the backlight subsystem too.
> >
> > And backlight is coupled with fbdev... Which is something I don't like.
> >
> > > I have a couple of patches queued up for 3.13 that rework parts of the
> > > driver, so it'd be good to know how you guys want to handle this.
> >
> > Well. I'm happy if somebody wants to maintain the backlight side. In
> > fact, I'd be happy if somebody would start restructuring it totally,
> > it's rather messy. The link with fbdev should be removed, and some
> > backlight drivers are actually panel drivers. However, perhaps Common
> > Display Framework is required until it can be fully cleaned.
> >
> > So... For the time being, I'm fine with merging pwm-backlight via any
> > tree that works best. I'm presuming here that backlight framework and
> > fbdev (for the parts that are relevant for backlight) are not really
> > being changed, so there shouldn't be conflicts.
> In that case I'll just take it through the PWM tree as I've done for the
> past year. I have some other changes planned for the PWM framework for
> the near future that'll create dependencies between the PWM tree and the
> pwm-backlight driver, so keeping them in one tree will make it easier to
> merge them.

Yes, I think so.
I want you to take the patches for pwm-backlight through the PWM tree,
as you have done.

> Longer term it probably makes sense, as you say, for someone to take
> over the backlight subsystem completely and give it the love it could
> really use. If Jingoo can do that, it'd be great. Perhaps it'd be a good
> idea to remove Richard as maintainer since he's obviously no longer
> responding to emails. Keeping him Cc'ed on all patches is just
> pointless.

OK, I will send the patch to remove Richard as maintainer.

I will make a git tree and mailing-list for the backlight subsystem later.
However, I am not certain when it will be done. :-(

Best regards,
Jingoo Han

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