[PATCH 0/2] [v5] pinctrl: qcom: add support for sparse GPIOs

Linus Walleij linus.walleij at linaro.org
Sat Oct 14 15:43:16 PDT 2017


On Thu, Oct 12, 2017 at 9:39 AM, Stephen Boyd <sboyd at codeaurora.org> wrote:

> For qcom platforms the driver will never be able to return the
> direction for these certain pins because reading the register is
> not allowed by the firmware. Doing so will cause the device to
> crash with a security violation.

So I guess the driver needs to know what pin registers it can't
access so the user does not get a gun to shoot in the foot with.

If we augment gpiolib to just handle -EACCES or something
(-EIO?) from the driver .get_direction() callback for these lines,
things should be smooth?

Yours,
Linus Walleij



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