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Date: Thu, 6 Sep 2018 23:23:41 +0200
From: Boris Brezillon <boris.brezillon@bootlin.com>
To: Bernhard Frauendienst <kernel@nospam.obeliks.de>
Cc: linux-mtd@lists.infradead.org
Subject: Re: [PATCH 0/3] Virtual MTD concat device driver
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On Thu, 6 Sep 2018 23:16:01 +0200
Bernhard Frauendienst <kernel@nospam.obeliks.de> wrote:

> Hi Boris,
> 
> On 06/09/18 23:03, Boris Brezillon wrote:
> > On Thu, 6 Sep 2018 22:59:49 +0200
> > Boris Brezillon <boris.brezillon@bootlin.com> wrote:
> >  
> >> Hi Bernhard,
> >>
> >> On Thu,  6 Sep 2018 18:14:10 +0200
> >> Bernhard Frauendienst <kernel@nospam.obeliks.de> wrote:
> >>  
> >>> Hi everybody,
> >>>
> >>> when porting my router board from a mach-file based OpenWRT target to a
> >>> device-tree based target, I found that there is no generic way to create
> >>> a mtd_concat device from within the dts. The following patches attempt
> >>> to provide that possibility.  
> >> There's a fundamental issue with this patch series: DT is supposed to
> >> represent the hardware, not how you want to use it, and clearly, your
> >> concatenated MTD dev is a virtual device, not a real one, so I doubt it
> >> will pass DT maintainers' review.  
> > BTW, did you consider doing that through the command line?  
> 
> Would you mind elaborating on that?

Something like:

mtdconcat=<virtdev1>=<realdev1>,<realdev2>;<virtdev2>=<realdev3>,<realdev4>

> 
> The biggest problem that I see is that I have to specify the fixed 
> partitions somewhere, and I would really like to keep that in the dts 
> file, where they would also be if it was only a single chip.

Send a v2, add the DT maintainers+ML in Cc, and you'll see what
happens.