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    mmc: core: don't override the CD GPIO level when "cd-inverted" is set · e3e4767b
    Martin Blumenstingl authored
    Since commit 89a5e15b ("gpio/mmc/of: Respect polarity in the device
    tree") gpiolib-of parses the "cd-gpios" property and flips the polarity
    if "cd-inverted" is also set. This results in the "cd-inverted" property
    being evaluated twice, which effectively makes it a no-op:
    - first in drivers/gpio/gpiolib-of.c (of_xlate_and_get_gpiod_flags) when
      setting up the CD GPIO
    - then again in drivers/mmc/core/slot-gpio.c (mmc_gpio_get_cd) when
      reading the CD GPIO value at runtime
    
    On boards which are using device-tree with the "cd-inverted" property
    being set any inserted card are not detected anymore. This is due to the
    MMC core treating the CD GPIO with the wrong polarity.
    
    Disable "override_cd_active_level" for the card detection GPIO which is
    parsed using mmc_of_parse. This fixes SD card detection on the boards
    which are currently using the "cd-inverted" device-tree property (tested
    on Meson8b Odroid-C1 and Meson8b EC-100).
    
    This does not remove the CD GPIO inversion logic from the MMC core
    because there's at least one driver (sdhci-pci-core for Intel BayTrail
    based boards) which still passes "override_cd_active_level = true" to
    mmc_gpiod_request_cd(). Due to lack of hardware for testing this is left
    untouched.
    In the future the GPIO inversion logic for both, card and read-only
    detection can be removed once no driver is using it anymore.
    
    Fixes: 89a5e15b
    
     ("gpio/mmc/of: Respect polarity in the device tree")
    Signed-off-by: default avatarMartin Blumenstingl <martin.blumenstingl@googlemail.com>
    Tested-by: default avatarAnand Moon <linux.amoon@gmail.com>
    Tested-by: default avatarLoys Ollivier <loys.ollivier@gmail.com>
    Acked-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
    Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    e3e4767b