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    Subject[PATCH 0/3] Support qcom pinctrl protected pins
    Date
    This patchset proposes a solution to describing the valid
    pins for a pin controller in a semi-generic way so that qcom
    platforms can expose the pins that are really available.

    Typically, this has been done by having drivers and firmware
    descriptions only use pins they know they have access to, and that
    still works now because we no longer read the pin direction at
    boot. But there are still some userspace drivers and debugfs facilities
    that don't know what pins are available and attempt to read everything
    they can. On qcom platforms, this may lead to a system hang, which isn't
    very nice behavior, even if root is the only user that can trigger it.

    The proposal is to describe the valid pins and then not allow things to
    cause problems by using the invalid pins. Obviously, the firmware may
    mess this up, so this is mostly a nice to have feature or a safety net
    so that things don't blow up easily.

    Stephen Boyd (3):
    gpiolib: Export gpiochip_irqchip_irq_valid() to drivers
    dt-bindings: pinctrl: Add a ngpios-ranges property
    pinctrl: qcom: Don't allow protected pins to be requested

    .../bindings/pinctrl/qcom,msm8996-pinctrl.txt | 6 ++
    drivers/gpio/gpiolib.c | 5 +-
    drivers/pinctrl/qcom/pinctrl-msm.c | 98 +++++++++++++++++++++-
    include/linux/gpio/driver.h | 3 +
    4 files changed, 106 insertions(+), 6 deletions(-)

    --
    The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
    a Linux Foundation Collaborative Project

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