Re: [PATCH 1/2] dt-bindings: at24: new optional property - write-protect-gpios

From: Andy Shevchenko
Date: Tue Dec 19 2017 - 17:25:13 EST


On Tue, Dec 19, 2017 at 6:14 PM, Bartosz Golaszewski <brgl@xxxxxxxx> wrote:
> AT24 EEPROMs have a write-protect pin, which - when pulled high -
> inhibits writes to the upper quadrant of memory (although it has been
> observed that on some chips it disables writing to the entire memory
> range).
>
> On some boards, this pin is connected to a GPIO and pulled high by
> default, which forces the user to manually change its state before
> writing. On linux this means that we either need to hog the line all
> the time, or set the GPIO value before writing from outside of the
> at24 driver.
>
> Add a new optional property to the device tree binding document, which
> allows to specify the GPIO line to which the write-protect pin is
> connected.
>

> + - write-protect-gpios: GPIO to which the write-protect pin of the chip is

The rule of thumb is to check what is de facto state of the properties
like this, i.e.

% git grep -n wp-gpio -- Documentation/ | wc -l
14
% git grep -n write-protect-gpio -- Documentation/ | wc -l
0

I think it means something.

--
With Best Regards,
Andy Shevchenko