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    SubjectRe: [PATCH v3.4-rc3] MTD: NAND: ams-delta: Fix request_mem_region() failure
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    On Tue, 2012-04-17 at 15:49 +0200, Janusz Krzysztofik wrote:
    > A call to request_mem_region() has been introduced in the omap-gpio
    > driver recently (commit 96751fcbe5438e95514b025e9cee7a6d38038f40,
    > "gpio/omap: Use devm_ API and add request_mem_region"). This change
    > prevented the Amstrad Delta NAND driver, which was doing the same in
    > order to take control over OMAP MPU I/O lines that the NAND device hangs
    > off, from loading successfully.
    >
    > There is another driver, omap-keypad, which also manipulates OMAP MPUIO
    > registers, but has never been calling request_mem_region() on startup,
    > so it's not affected by the change in the gpio-omap and works correctly.
    >
    > Drop request_mem_region() call and related bits from ams-delta NAND
    > driver.
    >
    > Created and tested against linux-3.4-rc3.
    >
    > Signed-off-by: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl>

    How about race conditions? Where is the guarantee that these 2 drivers
    won't affect each other when doing I/O at the same time to the same HW
    resources?

    --
    Best Regards,
    Artem Bityutskiy
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