Re: [PATCH v2] gpio: gpio-pca953x, Add get_multiple function

From: Linus Walleij
Date: Thu Apr 16 2020 - 07:25:23 EST


On Tue, Apr 14, 2020 at 5:30 PM Paul Thomas <pthomas8589@xxxxxxxxx> wrote:

> Implement a get_multiple function for gpio-pca953x. If a driver
> leaves get_multiple unimplemented then gpio_chip_get_multiple()
> in gpiolib.c takes care of it by calling chip->get() as needed.
> For i2c chips this is very inefficient. For example if you do an
> 8-bit read then instead of a single i2c transaction there are
> 8 transactions reading the same byte!
>
> This has been tested with max7312 chips on a 5.2 kernel.
>
> Signed-off-by: Paul Thomas <pthomas8589@xxxxxxxxx>
> ---
> changes from v1: rebased to 5.7-rc1

Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Since I know Bartosz is queueing other patches for this driver I
let him pick it up.

Yours,
Linus Walleij