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    Subject[PATCH 0/9] gpio: batch #1: remove modular usage from non-modular drivers
    Date
    For GPIO, I've divided up the the audit of modular usage in non-modular
    drivers into three categories to ease review and limit the batch size.
    The breakdown of the three groups is as follows:

    1) just replacement of modular macros with their non-modular equivalents
    that CPP would have inserted anyway ; this means runtime equivalence
    and actually also binary equivalence.

    [This lot represents #1, which are essentially the "free" ones that have
    essentially zero impact beyond the original desired cleanup goal itself.]

    2) as per #1 but also with the removal of unused/orphaned __exit functions
    that could never be called/exercised. This also maintains runtime
    equivalence, but since the unused __exit function is gone, there is a
    reduction in the object file size and hence not binary equivalence, eg:
    before: -rw-rw-r-- 1 8828 drivers/gpio/gpio-rc5t583.o
    after: -rw-rw-r-- 1 7396 drivers/gpio/gpio-rc5t583.o

    3) as per #2 but also with the removal of a ".remove" function that is
    hooked into the driver struct. This ".remove" function would of
    course not be called from the __exit function since that is never run.
    However in theory, someone could have triggered it via sysfs unbind,
    even though there isn't a sensible use case for doing so. So to cover
    that possibility, we've also disabled sysfs unbind in these drivers.

    I will send #2 once this #1 is finalized/merged and #3 once #2 is merged.

    For anyone new to the underlying goal of this cleanup, we are trying to
    not use module support for code that can never be built as a module since:

    (1) it is easy to accidentally write unused module_exit and remove code
    (2) it can be misleading when reading the source, thinking it can be
    modular when the Makefile and/or Kconfig prohibit it
    (3) it requires the include of the module.h header file which in turn
    includes nearly everything else, thus adding to CPP overhead.
    (4) it gets copied/replicated into other code and spreads like weeds.

    Build tested for arm and arm64 on 4.6-rc1 to ensure no silly typos exist.

    Paul.
    ---

    Cc: Alexandre Courbot <gnurou@gmail.com>
    Cc: Baruch Siach <baruch@tkos.co.il>
    Cc: bcm-kernel-feedback-list@broadcom.com
    Cc: Feng Kan <fkan@apm.com>
    Cc: Jonas Jensen <jonas.jensen@gmail.com>
    Cc: Jun Nie <jun.nie@linaro.org>
    Cc: Linus Walleij <linus.walleij@linaro.org>
    Cc: Ray Jui <rjui@broadcom.com>
    Cc: Wu Guoxing <b39297@freescale.com>
    Cc: linux-gpio@vger.kernel.org

    Paul Gortmaker (9):
    drivers/gpio: make gpio-bcm-kona.c explicitly non-modular
    drivers/gpio: make gpio-mb86s7x.c driver explicitly non-modular
    drivers/gpio: make gpio-mc9s08dz60.c explicitly non-modular
    drivers/gpio: make gpio-moxart.c explicitly non-modular
    drivers/gpio: make gpio-mvebu.c explicitly non-modular
    drivers/gpio: make gpio-pl061.c explicitly non-modular
    drivers/gpio: make gpio-sta2x11.c explicitly non-modular
    drivers/gpio: make gpio-xgene.c explicitly non-modular
    drivers/gpio: make gpio-zx.c explicitly non-modular

    drivers/gpio/gpio-bcm-kona.c | 14 +++++---------
    drivers/gpio/gpio-mb86s7x.c | 8 +-------
    drivers/gpio/gpio-mc9s08dz60.c | 12 ++----------
    drivers/gpio/gpio-moxart.c | 7 +------
    drivers/gpio/gpio-mvebu.c | 5 ++---
    drivers/gpio/gpio-pl061.c | 12 ++++--------
    drivers/gpio/gpio-sta2x11.c | 8 ++------
    drivers/gpio/gpio-xgene.c | 9 +--------
    drivers/gpio/gpio-zx.c | 14 ++++++--------
    9 files changed, 24 insertions(+), 65 deletions(-)

    --
    2.6.1

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