• Christian Lamparter's avatar
    dt-bindings: pinctrl: qcom: add gpio-ranges, gpio-reserved-ranges · c1e802f6
    Christian Lamparter authored
    This patch adds the gpio-ranges and gpio-reserved-ranges property
    definitions to the binding text files supported by the pinctrl-msm
    driver framework.
    
    gpio-ranges:
    For DT-based platforms the pinctrl-msm framework currently relies
    on the deprecated-for-DT gpiochip_add_pin_range() function to add
    the range of GPIOs to be handled by the pin controller. Due to
    interactions within gpiolib code, this causes the pinctrl-msm
    driver to bail out (-517) during boot when a gpio-hog is declared.
    This can be fatal and cause the system to not boot or reset
    (for a detailed explanation and call-trace, refer to patch:
    "pinctrl: msm: fix gpio-hog related boot issues" in this series).
    
    gpio-reserved-ranges:
    The binding has been added as a precaution since the TrustZone
    firmware (aka QSEE), which is running as the hypervisor, might
    have reserved certain, but undisclosed pins. Hence reading or
    writing to the registers for those pins will cause an
    XPU violation and this subsequently crashes the kernel.
    Signed-off-by: default avatarChristian Lamparter <chunkeey@gmail.com>
    Reviewed-by: default avatarRob Herring <robh@kernel.org>
    Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    c1e802f6
qcom,ipq4019-pinctrl.txt 3.03 KB