Re: [PATCH] pinctrl: qcom: qdf2xxx: expose only some GPIO pins

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Thu, Jun 22, 2017 at 10:54 PM, Timur Tabi <timur@xxxxxxxxxxxxxx> wrote:

> On Qualcomm Technologies QDF2xxx platforms, only a subset of the GPIOs
> are actually available to the HLOS.  The others are blocked by the XPU,
> and any attempt to access them will cause an XPU violation that halts
> the system.

That's a bummer. Looking for Björn's review on this patch.

> Instead, the ACPI table now lists only specific GPIOs that are exposed
> externally as generic GPIO pins.

The ACPI table or the device tree property "gpios" right?

(But maybe this system is only using ACPI.)

> To maintain consistency, the GPIOs are
> enumerated 0 .. (N-1) as before, so that "gpio0" is really whatever is
> the first GPIO listed in ACPI.  The actual mapping is available via
> /sys/kernel/debug/gpio.

I think using "lsgpio" fron tools/gpio/lsgpio.c is better to inspect
the available GPIOs.

If you haven't tested the GPIO tools, please try it out.

Yours,
Linus Walleij
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