Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20200414152843.32129-1-pthomas8589@gmail.com>
In-Reply-To: <20200414152843.32129-1-pthomas8589@gmail.com>
From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Thu, 16 Apr 2020 13:22:23 +0200
Message-ID: <CACRpkdaPc-rxNmdq7KFKZ-Qi7Tqy2RJ5Lkcv-8bTAh0GX7VygQ@mail.gmail.com>
Subject: Re: [PATCH v2] gpio: gpio-pca953x, Add get_multiple function
To:     Paul Thomas <pthomas8589@gmail.com>
Cc:     Bartosz Golaszewski <bgolaszewski@baylibre.com>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Tue, Apr 14, 2020 at 5:30 PM Paul Thomas <pthomas8589@gmail.com> 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@gmail.com>
> ---
>  changes from v1: rebased to 5.7-rc1

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

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

Yours,
Linus Walleij