Re: [PATCH] mtd: rawnand: ams-delta: Drop board specific partition info

From: Aaro Koskinen <aaro.koskinen@iki.fi>
To: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Cc: Boris Brezillon <bbrezillon@kernel.org>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Richard Weinberger <richard@nod.at>,
	David Woodhouse <dwmw2@infradead.org>,
	Brian Norris <computersforpeace@gmail.com>,
	Marek Vasut <marek.vasut@gmail.com>,
	Tony Lindgren <tony@atomide.com>,
	linux-mtd@lists.infradead.org, linux-omap@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mtd: rawnand: ams-delta: Drop board specific partition info
Date: Sun, 24 Mar 2019 20:59:32 +0200	[thread overview]
Message-ID: <20190324185932.GA24594@darkstar.musicnaut.iki.fi> (raw)
In-Reply-To: <2631901.52Nzq63B5o@z50>

Hi,

On Sun, Mar 24, 2019 at 05:48:22PM +0100, Janusz Krzysztofik wrote:
> Hi Aaro,
> 
> Thanks for your review.
> 
> On Wednesday, March 20, 2019 2:16:30 AM CET Aaro Koskinen wrote:
> > On Tue, Mar 19, 2019 at 11:37:18PM +0100, Janusz Krzysztofik wrote:
> > > After recent modifications, only a hardcoded partition info makes
> > > the driver device specific.  Other than that, the driver uses GPIO
> > > exclusively and can be used on any hardware.
> > > 
> > > Drop the partition info and use MTD partition parser with default
> > > list of partition types instead.
> > > 
> > > Amstrad Delta users should append the followig partition info to their
> >                                         ^^^^^^^^
> > Should be "following".
> > 
> > > kernel command line, possibly by embedding it in CONFIG_CMDLINE:
> > > mtdparts=ams-delta-nand:3584k(Kernel),256k(u-boot),256k(u-boot_params),\
> > > 256k(Amstrad_LDR),27m(File_system),768k(PBL_reserved).  For their
> > > convenience, select CONFIG_MTD_CMDLINE_PARTS  symbol from that board
> > > Kconfig automatically if this NAND driver is also selected.
> > > 
> > > Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
> > > Cc: Tony Lindgren <tony@atomide.com>
> > 
> > Could we move the fixed partition setup to the board file
> > instead? Otherwise this kind of change is not really nice for the users,
> > as it will likely break existing setups. The default partition layout
> > should remain the same.
> 
> I'm wondering if it would be acceptable to pass partition info from a .dts 
> file.  I think that would be a better, more modern approach than adding a new 
> header under include/linux/platform_data.

Hmm, I thought there was some generic way to define partitions without
adding any new headers. But if that is not possible, then I guess your
CMDLINE proposal is the preferred one..

A.