[PATCH] powerpc/8xx: Remove Kconfig symbol FADS

[PATCH] powerpc/8xx: Remove Kconfig symbol FADS

[Paul Bolle]

Commit 39eb56da2b53 ("pcmcia: Remove m8xx_pcmcia driver") removed the
only driver that used CONFIG_FADS. Setting the Kconfig symbol FADS is
pointless since that commit. Remove it.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
---
Done on top of next-20140923. Tested with "git grep" only.

Another cleanup might be to remove MPC8XXFADS (or "FADS") from the "8xx
Machine Type" choice. Is there any reason left to pick "FADS" as a
machine type?

 arch/powerpc/platforms/8xx/Kconfig | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/powerpc/platforms/8xx/Kconfig b/arch/powerpc/platforms/8xx/Kconfig
index 247fdea0c8be..831f2e718b06 100644
--- a/arch/powerpc/platforms/8xx/Kconfig
+++ b/arch/powerpc/platforms/8xx/Kconfig
@@ -1,6 +1,3 @@
-config FADS
-	bool
-
 config CPM1
 	bool
 	select CPM
@@ -13,7 +10,6 @@ choice
 
 config MPC8XXFADS
 	bool "FADS"
-	select FADS
 
 config MPC86XADS
 	bool "MPC86XADS"
-- 
1.9.3

Re: powerpc/8xx: Remove Kconfig symbol FADS

[Scott Wood]

On Wed, Sep 24, 2014 at 10:06:19AM +0200, Paul Bolle wrote:
> Commit 39eb56da2b53 ("pcmcia: Remove m8xx_pcmcia driver") removed the
> only driver that used CONFIG_FADS. Setting the Kconfig symbol FADS is
> pointless since that commit. Remove it.
> 
> Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
> ---
> Done on top of next-20140923. Tested with "git grep" only.
> 
> Another cleanup might be to remove MPC8XXFADS (or "FADS") from the "8xx
> Machine Type" choice. Is there any reason left to pick "FADS" as a
> machine type?

Nothing references MPC8XXFADS, so yes, it can be removed.

-Scott

Re: powerpc/8xx: Remove Kconfig symbol FADS

[Scott Wood]

On Wed, Sep 24, 2014 at 10:06:19AM +0200, Paul Bolle wrote:
> Commit 39eb56da2b53 ("pcmcia: Remove m8xx_pcmcia driver") removed the
> only driver that used CONFIG_FADS. Setting the Kconfig symbol FADS is
> pointless since that commit. Remove it.
> 
> Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
> ---
> Done on top of next-20140923. Tested with "git grep" only.
> 
> Another cleanup might be to remove MPC8XXFADS (or "FADS") from the "8xx
> Machine Type" choice. Is there any reason left to pick "FADS" as a
> machine type?

Nothing references MPC8XXFADS, so yes, it can be removed.

-Scott

Re: powerpc/8xx: Remove Kconfig symbol FADS

[Paul Bolle]

On Thu, 2014-11-06 at 21:50 -0600, Scott Wood wrote:
> On Wed, Sep 24, 2014 at 10:06:19AM +0200, Paul Bolle wrote: 
> > Another cleanup might be to remove MPC8XXFADS (or "FADS") from the "8xx
> > Machine Type" choice. Is there any reason left to pick "FADS" as a
> > machine type?
> 
> Nothing references MPC8XXFADS, so yes, it can be removed.

I'll try to look into this. For the (verbose) reasons below I'll do that
in a separate patch, if I ever get that far. What follows is mostly a
note to self.

MPC8XXFADS is indeed not referenced anywhere. But it's one of the
entries in the "8xx Machine Type" choice. And it's common for choice
blocks the have a "none of the above" entry. Ie, an entry that allows to
configure nothing. There's a chance MPC8XXFADS is currently used for
that role. (This is easier to determine for people that - unlike me -
know what all the symbols in this choice mean. To me they 're basically
random strings.)

Actually, there's an obscure "optional" Kconfig keyword that appears to
be added to take care of this use case. It's currently used exactly
twice in the tree, in smaller architectures: once in arch/avr32/ and
once in arch/sh/. This implies this "optional" keyword is used very
little. I'll have to look carefully to see whether it works as
advertised.


Paul Bolle

Re: powerpc/8xx: Remove Kconfig symbol FADS

[Paul Bolle]

On Thu, 2014-11-06 at 21:50 -0600, Scott Wood wrote:
> On Wed, Sep 24, 2014 at 10:06:19AM +0200, Paul Bolle wrote: 
> > Another cleanup might be to remove MPC8XXFADS (or "FADS") from the "8xx
> > Machine Type" choice. Is there any reason left to pick "FADS" as a
> > machine type?
> 
> Nothing references MPC8XXFADS, so yes, it can be removed.

I'll try to look into this. For the (verbose) reasons below I'll do that
in a separate patch, if I ever get that far. What follows is mostly a
note to self.

MPC8XXFADS is indeed not referenced anywhere. But it's one of the
entries in the "8xx Machine Type" choice. And it's common for choice
blocks the have a "none of the above" entry. Ie, an entry that allows to
configure nothing. There's a chance MPC8XXFADS is currently used for
that role. (This is easier to determine for people that - unlike me -
know what all the symbols in this choice mean. To me they 're basically
random strings.)

Actually, there's an obscure "optional" Kconfig keyword that appears to
be added to take care of this use case. It's currently used exactly
twice in the tree, in smaller architectures: once in arch/avr32/ and
once in arch/sh/. This implies this "optional" keyword is used very
little. I'll have to look carefully to see whether it works as
advertised.


Paul Bolle

Re: powerpc/8xx: Remove Kconfig symbol FADS

[Scott Wood]

On Fri, 2014-11-07 at 09:48 +0100, Paul Bolle wrote:
> On Thu, 2014-11-06 at 21:50 -0600, Scott Wood wrote:
> > On Wed, Sep 24, 2014 at 10:06:19AM +0200, Paul Bolle wrote: 
> > > Another cleanup might be to remove MPC8XXFADS (or "FADS") from the "8xx
> > > Machine Type" choice. Is there any reason left to pick "FADS" as a
> > > machine type?
> > 
> > Nothing references MPC8XXFADS, so yes, it can be removed.
> 
> I'll try to look into this. For the (verbose) reasons below I'll do that
> in a separate patch, if I ever get that far. What follows is mostly a
> note to self.

Yes, make it a separate patch -- I've already got this patch queued up.

> MPC8XXFADS is indeed not referenced anywhere. But it's one of the
> entries in the "8xx Machine Type" choice. And it's common for choice
> blocks the have a "none of the above" entry. Ie, an entry that allows to
> configure nothing. There's a chance MPC8XXFADS is currently used for
> that role. (This is easier to determine for people that - unlike me -
> know what all the symbols in this choice mean. To me they 're basically
> random strings.)

It's not a "none of the above" option.  It's a board type that was
supported in arch/ppc, and only some remnants made it over to
arch/powerpc.  If you don't pick a machine type that results in a
define_machine() struct (with a probe function that matches the device
tree), the kernel will not boot.

-Scott

Re: powerpc/8xx: Remove Kconfig symbol FADS

[Scott Wood]

On Fri, 2014-11-07 at 09:48 +0100, Paul Bolle wrote:
> On Thu, 2014-11-06 at 21:50 -0600, Scott Wood wrote:
> > On Wed, Sep 24, 2014 at 10:06:19AM +0200, Paul Bolle wrote: 
> > > Another cleanup might be to remove MPC8XXFADS (or "FADS") from the "8xx
> > > Machine Type" choice. Is there any reason left to pick "FADS" as a
> > > machine type?
> > 
> > Nothing references MPC8XXFADS, so yes, it can be removed.
> 
> I'll try to look into this. For the (verbose) reasons below I'll do that
> in a separate patch, if I ever get that far. What follows is mostly a
> note to self.

Yes, make it a separate patch -- I've already got this patch queued up.

> MPC8XXFADS is indeed not referenced anywhere. But it's one of the
> entries in the "8xx Machine Type" choice. And it's common for choice
> blocks the have a "none of the above" entry. Ie, an entry that allows to
> configure nothing. There's a chance MPC8XXFADS is currently used for
> that role. (This is easier to determine for people that - unlike me -
> know what all the symbols in this choice mean. To me they 're basically
> random strings.)

It's not a "none of the above" option.  It's a board type that was
supported in arch/ppc, and only some remnants made it over to
arch/powerpc.  If you don't pick a machine type that results in a
define_machine() struct (with a probe function that matches the device
tree), the kernel will not boot.

-Scott