Commit Graph

12 Commits

Author SHA1 Message Date
Nicolas Pitre 237e3ad0f1 Kconfig: Introduce the "imply" keyword
The "imply" keyword is a weak version of "select" where the target
config symbol can still be turned off, avoiding those pitfalls that come
with the "select" keyword.

This is useful e.g. with multiple drivers that want to indicate their
ability to hook into a secondary subsystem while allowing the user to
configure that subsystem out without also having to unset these drivers.

Currently, the same effect can almost be achieved with:

config DRIVER_A
	tristate

config DRIVER_B
	tristate

config DRIVER_C
	tristate

config DRIVER_D
	tristate

[...]

config SUBSYSTEM_X
	tristate
	default DRIVER_A || DRIVER_B || DRIVER_C || DRIVER_D || [...]

This is unwieldy to maintain especially with a large number of drivers.
Furthermore, there is no easy way to restrict the choice for SUBSYSTEM_X
to y or n, excluding m, when some drivers are built-in. The "select"
keyword allows for excluding m, but it excludes n as well. Hence
this "imply" keyword.  The above becomes:

config DRIVER_A
	tristate
	imply SUBSYSTEM_X

config DRIVER_B
	tristate
	imply SUBSYSTEM_X

[...]

config SUBSYSTEM_X
	tristate

This is much cleaner, and way more flexible than "select". SUBSYSTEM_X
can still be configured out, and it can be set as a module when none of
the drivers are configured in or all of them are modular.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-2-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:33 +01:00
Andreas Ruprecht c2264564df kconfig: warn of unhandled characters in Kconfig commands
In Kconfig, definitions of options take the following form:
"<COMMAND> <PARAM> <PARAM> ...". COMMANDs and PARAMs are treated
slightly different by the underlying parser.

While commit 2e0d737fc7 ("kconfig: don't silently ignore unhandled
characters") introduced a warning for unsupported characters around
PARAMs, it does not cover situations where a COMMAND has additional
characters before it.

This change makes Kconfig emit a warning if superfluous characters
are found before COMMANDs. As the 'help' statement sometimes is
written as '---help---', the '-' character would now also be regarded
as unhandled and generate a warning. To avoid that, '-' is added to
the list of allowed characters, and the token '---help---' is included
in the zconf.gperf file.

Reported-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Andreas Ruprecht <andreas.ruprecht@fau.de>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
Tested-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
2015-08-19 17:05:39 +02:00
Josh Triplett 5d2acfc7b9 kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT
"make allnoconfig" exists to ease testing of minimal configurations.
Documentation/SubmitChecklist includes a note to test with allnoconfig.
This helps catch missing dependencies on common-but-not-required
functionality, which might otherwise go unnoticed.

However, allnoconfig still leaves many symbols enabled, because they're
hidden behind CONFIG_EMBEDDED or CONFIG_EXPERT.  For instance, allnoconfig
still has CONFIG_PRINTK and CONFIG_BLOCK enabled, so drivers don't
typically get build-tested with those disabled.

To address this, introduce a new Kconfig option "allnoconfig_y", used on
symbols which only exist to hide other symbols.  Set it on CONFIG_EMBEDDED
(which then selects CONFIG_EXPERT).  allnoconfig will then disable all the
symbols hidden behind those.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-07 16:36:09 -07:00
Arnaud Lacombe 61f956f576 kconfig: constify `kconf_id_lookup'
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-06-09 14:04:42 -04:00
Arnaud Lacombe 86e187ff9b kconfig: add an option to determine a menu's visibility
This option is aimed to add the possibility to control a menu's visibility
without adding dependency to the expression to all the submenu.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2010-11-22 11:27:17 -02:00
Josh Triplett 6516657180 kconfig: Mark various internal functions static
kconfig's keyword hash, lexer, and parser define various functions used
only locally.  Declare these functions as static, and regenerate the
corresponding generated files.

Signed-off-by: Josh Triplett <josh@joshtriplett.org>
2009-11-15 15:00:16 -08:00
Adrian Bunk 9649ef878d kconfig: remove "enable"
Kconfig had a synonym "enable" for "select" that was neither documented
nor used.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:21:18 +01:00
Roman Zippel 93449082e9 kconfig: environment symbol support
Add the possibility to import a value from the environment into kconfig
via the option syntax. Beside flexibility this has the advantage
providing proper dependencies.
Documented the options syntax.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2008-01-28 23:14:39 +01:00
Adrian Bunk 247537b9a2 kconfig: syntax cleanup - drop support for "depends/requires/def_boolean"
Remove the following redundant and never or rarely used kconfig syntax:

- "def_boolean" (same as "def_bool")
- "requires" (same as "depends on")
- "depends" (same as "depends on")

This patch contains the code changes and Kconfig updates.
The shipped files are in next patch to let actual codechange stand out.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2007-10-12 21:20:32 +02:00
Roman Zippel f6a88aa860 kconfig: add symbol option config syntax
This adds the general framework to the parser to define options for config
symbols with a syntax like:

config FOO
	option bar[="arg"]

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
2006-06-09 07:31:30 +02:00
Roman Zippel 3370f9f0d9 [PATCH] kconfig: simplify symbol type parsing
This simplifies the parser a bit by merging the various symbol types into a
single token and adds the type to the keyword hash.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:54 -08:00
Roman Zippel 7a88488bbc [PATCH] kconfig: use gperf for kconfig keywords
Use gperf to generate a hash for the kconfig keywords.  This greatly reduces
the size of the generated scanner and makes it easier to extend kconfig.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-09 07:55:53 -08:00