Re: [PATCH] mtd: rawnand: omap2: Actually prevent invalid configuration and build error

[Guenter Roeck]

On 3/4/22 07:54, Miquel Raynal wrote:
> Hi Guenter, Roger,
>
> rdunlap@xxxxxxxxxxxxx wrote on Sat, 26 Feb 2022 22:55:28 -0800:
>
> > On 2/19/22 16:44, Guenter Roeck wrote:
> > > On Sat, Feb 19, 2022 at 09:36:00PM +0200, Roger Quadros wrote:
> > > > The root of the problem is that we are selecting symbols that have
> > > > dependencies. This can cause random configurations that can fail.
> > > > The cleanest solution is to avoid using select.
> > > >
> > > > This driver uses interfaces from the OMAP_GPMC driver so we have to
> > > > depend on it instead.
> > > >
> > > > Fixes: 4cd335dae3cf ("mtd: rawnand: omap2: Prevent invalid configuration and build error")
> > > > Signed-off-by: Roger Quadros <rogerq@xxxxxxxxxx>
> > >
> > > Tested-by: Guenter Roeck <linux@xxxxxxxxxxxx>
> >
> > Tested-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
>
> Sorry for noticing that just now, but there is still a problem with
> this patch: we now always compile-in the OMAP_GPMC driver whenever we
> need the NAND controller, even though it is not needed. This grows the
> kernel for no reason.

Sorry, you lost me.

> In fact, Roger once said:
>
> 	"We will figure out how to enable OMAP_GPMC for K3 architecture
> 	some other way."
>
> It turns out this is not what was finally proposed. Could we try yet
> another solution?
>
> > Thanks.
> >
> > >    
> > > > ---
> > > >   drivers/mtd/nand/raw/Kconfig | 3 +--
> > > >   1 file changed, 1 insertion(+), 2 deletions(-)
> > > >
> > > > diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
> > > > index 36e697456ec4..9b078e78f3fa 100644
> > > > --- a/drivers/mtd/nand/raw/Kconfig
> > > > +++ b/drivers/mtd/nand/raw/Kconfig
> > > > @@ -42,8 +42,7 @@ config MTD_NAND_OMAP2
> > > >   	tristate "OMAP2, OMAP3, OMAP4 and Keystone NAND controller"
> > > >   	depends on ARCH_OMAP2PLUS || ARCH_KEYSTONE || ARCH_K3 || COMPILE_TEST
> > > >   	depends on HAS_IOMEM
> > > > -	select MEMORY
> > > > -	select OMAP_GPMC
> > > > +	depends on OMAP_GPMC

No matter if select or depend, both result in OMAP_GPMC enabled
if MTD_NAND_OMAP2={m,y}, and both suggest that OMAP_GPMC is
needed for MTD_NAND_OMAP2. That conflicts with

 we now always compile-in the OMAP_GPMC driver whenever we
 need the NAND controller, even though it is not needed
                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

If it isn't needed, why the dependency in the first place ?
Also, commit 4cd335dae3cf2 states "this driver depends on OMAP_GPMC
driver and uses symbols from there". Are you saying that this is not
correct ?

Guenter