Re: [PATCH 1/2] gpio: Add gpio latch driver

[Linus Walleij]

On Thu, Aug 25, 2022 at 11:41 AM Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> wrote:

> This driver implements a GPIO multiplexer based on latches connected to
> other GPIOs. A set of data GPIOs is connected to the data input of
> multiple latches. The clock input of each latch is driven by another
> set of GPIOs. With two 8-bit latches 10 GPIOs can be multiplexed into
> 16 GPIOs. GPOs might be a better term as in fact the multiplexed pins
> are output only.
>
> Signed-off-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>

Take a close look at the other forwarding driver:
drivers/gpio/gpio-aggregator.c

Especially (as pointed out by Marco) the sleeping/non-sleeping calls.

There was a lot of discussion around that patch before we got the
forwarding of GPIOs into a nice working shape.

Also get Geert to review this because he knows what you need to
do. :)

Yours,
Linus Walleij