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

From: Janusz Krzysztofik
Date: Sun Mar 24 2019 - 16:30:40 EST


Hi,

On Sunday, March 24, 2019 7:59:32 PM CET Aaro Koskinen wrote:
> 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@xxxxxxxxx>
> > > > Cc: Tony Lindgren <tony@xxxxxxxxxxx>
> > >
> > > 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..

I could for example reuse (or abuse) struct gpio_nand_platdata defined in
include/linux/mtd/nand-gpio.h for use with drivers/mtd/nand/raw/gpio.c, but
I'm not sure if hi-jacking a header that belongs to another driver would be an
elegant solution.

Thanks,
Janusz


>
> A.
>