Re: [PATCH v3 2/3] gpiolib: Support 'gpio-reserved-ranges' property

From: Andy Shevchenko
Date: Wed Mar 21 2018 - 13:59:20 EST


On Wed, 2018-03-21 at 09:58 -0700, Stephen Boyd wrote:
> From: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
>
> Some qcom platforms make some GPIOs or pins unavailable for use by
> non-secure operating systems, and thus reading or writing the
> registers
> for those pins will cause access control issues. Add support for a DT
> property to describe the set of GPIOs that are available for use so
> that
> higher level OSes are able to know what pins to avoid reading/writing.
> Non-DT platforms can add support by directly updating the
> chip->valid_mask.

> Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxxxxxx>
> Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>

Hmm...

> + gpiochip->valid_mask = kcalloc(BITS_TO_LONGS(gpiochip-
> >ngpio),
> + sizeof(long), GFP_KERNEL);

Just noticed that kcalloc is superfluous here.
kmalloc_array() would be enough.

> + if (!gpiochip->valid_mask)
> + return -ENOMEM;
> +
> + /* Assume by default all GPIOs are valid */
> + bitmap_fill(gpiochip->valid_mask, gpiochip->ngpio);


--
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy