From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jingoo Han Date: Fri, 27 Sep 2013 03:28:21 +0000 Subject: Re: [PATCH v2] pwm-backlight: allow for non-increasing brightness levels Message-Id: <017a01cebb31$9df90f60$d9eb2e20$%han@samsung.com> List-Id: References: <1379869196-19377-1-git-send-email-mikedunn@newsguy.com> <5244065A.8010408@ti.com> <20130926115108.GA1680@ulmo> <524423B6.4070609@ti.com> In-Reply-To: <524423B6.4070609-l0cyMroinI0@public.gmane.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: 'Tomi Valkeinen' , 'Thierry Reding' Cc: 'Mike Dunn' , 'Richard Purdie' , 'Jean-Christophe Plagniol-Villard' , 'Grant Likely' , 'Rob Herring' , linux-pwm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-fbdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, 'Robert Jarzmik' , 'Marek Vasut' , 'Laurent Pinchart' , 'Jingoo Han' On Thursday, September 26, 2013 9:08 PM, 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. +cc Laurent Pinchart, Yes, right. The backlight should be de-coupled with fbdev. I remember that Laurent Pinchart was doing this patch. Laurent Pinchart, Would you let us know your plan about this? :-) > > > 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. I think that some backlight drivers can be moved to 'Common Display Framework', after 'Common Display Framework' is merged. But, I am not sure, when it will be completed. Best regards, Jingoo Han > > 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. > > Tomi >