[PATCH] mmc: dw_mmc: Remove architecture dependency

[PATCH] mmc: dw_mmc: Remove architecture dependency

[Andrew Bresticker]

The dw_mmc host may also be present on non-ARC/ARM SoCs (e.g. MIPS)
and the driver itself does not appear to depend on any particular
architecture(s).

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
---
 drivers/mmc/host/Kconfig | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index a565254..15b110a 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -563,7 +563,6 @@ config SDH_BFIN_MISSING_CMD_PULLUP_WORKAROUND
 
 config MMC_DW
 	tristate "Synopsys DesignWare Memory Card Interface"
-	depends on ARC || ARM
 	help
 	  This selects support for the Synopsys DesignWare Mobile Storage IP
 	  block, this provides host support for SD and MMC interfaces, in both
-- 
2.1.0.rc2.206.gedb03e5

Re: [PATCH] mmc: dw_mmc: Remove architecture dependency

[Alim Akhtar]

Hi Andrew,

On Wed, Aug 13, 2014 at 11:02 PM, Andrew Bresticker
<abrestic@chromium.org> wrote:
> The dw_mmc host may also be present on non-ARC/ARM SoCs (e.g. MIPS)
> and the driver itself does not appear to depend on any particular
> architecture(s).
>
> Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
> ---
>  drivers/mmc/host/Kconfig | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> index a565254..15b110a 100644
> --- a/drivers/mmc/host/Kconfig
> +++ b/drivers/mmc/host/Kconfig
> @@ -563,7 +563,6 @@ config SDH_BFIN_MISSING_CMD_PULLUP_WORKAROUND
>
>  config MMC_DW
>         tristate "Synopsys DesignWare Memory Card Interface"
> -       depends on ARC || ARM

I am not sure if just removing _depends_ is good vs adding another
architecture(s) dependency here.
There are n number of places in Kconfig where this _depends_ runs up
to well over 10 entries.
What about config like MMC_DW_EXYNOS and MMC_DW_K3 which depends on
MMC_DW? Is it ok to expose them as well for architectures which might
not contains these variants?

One way I found this useful, one need not worry about finding MMC_DW
in there arch default menu-config, this will just appear, go and
select it.

Lets see what others think about this.

>         help
>           This selects support for the Synopsys DesignWare Mobile Storage IP
>           block, this provides host support for SD and MMC interfaces, in both
> --
> 2.1.0.rc2.206.gedb03e5
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html



-- 
Regards,
Alim

Re: [PATCH] mmc: dw_mmc: Remove architecture dependency

[Arnd Bergmann]

On Thursday 14 August 2014 03:51:43 Alim Akhtar wrote:
> On Wed, Aug 13, 2014 at 11:02 PM, Andrew Bresticker
> <abrestic@chromium.org> wrote:
> > The dw_mmc host may also be present on non-ARC/ARM SoCs (e.g. MIPS)
> > and the driver itself does not appear to depend on any particular
> > architecture(s).
> >
> > Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
> > ---
> >  drivers/mmc/host/Kconfig | 1 -
> >  1 file changed, 1 deletion(-)
> >
> > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
> > index a565254..15b110a 100644
> > --- a/drivers/mmc/host/Kconfig
> > +++ b/drivers/mmc/host/Kconfig
> > @@ -563,7 +563,6 @@ config SDH_BFIN_MISSING_CMD_PULLUP_WORKAROUND
> >
> >  config MMC_DW
> >         tristate "Synopsys DesignWare Memory Card Interface"
> > -       depends on ARC || ARM
> 
> I am not sure if just removing _depends_ is good vs adding another
> architecture(s) dependency here.
> There are n number of places in Kconfig where this _depends_ runs up
> to well over 10 entries.
> What about config like MMC_DW_EXYNOS and MMC_DW_K3 which depends on
> MMC_DW? Is it ok to expose them as well for architectures which might
> not contains these variants?
> 
> One way I found this useful, one need not worry about finding MMC_DW
> in there arch default menu-config, this will just appear, go and
> select it.
> 
> Lets see what others think about this.

In general, it's best to have specific dependencies on the subsystem
a driver uses. You probably need something like

	depends on HAS_IOMEM && COMMON_CLK && REGULATOR
	depends on COMPILE_TEST || ARC || ARM || MIPS

to cover all the possible cases. The specific options are probably
not the ones I listed above, but you should get the idea. Most importantly,
you don't want to allow building the driver on architectures on which
it can't compile.

	Arnd

Re: [PATCH] mmc: dw_mmc: Remove architecture dependency

[Andrew Bresticker]

> In general, it's best to have specific dependencies on the subsystem
> a driver uses. You probably need something like
>
>         depends on HAS_IOMEM && COMMON_CLK && REGULATOR
>         depends on COMPILE_TEST || ARC || ARM || MIPS
>
> to cover all the possible cases. The specific options are probably
> not the ones I listed above, but you should get the idea. Most importantly,
> you don't want to allow building the driver on architectures on which
> it can't compile.

The only compile-time dependencies I see are HAS_IOMEM (which MMC
already depends on) and HAS_DMA.  There isn't any compile-time
dependency on COMMON_CLK, REGULATOR, GPIOLIB, OF, etc.  I've compiled
it successfully for a few non-ARM/ARC architectures, though that
certainly isn't an exhaustive test.  To be safe though, perhaps I'll
just update the architecture dependency to include MIPS ||
COMPILE_TEST as you suggested.