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SubjectRe: [PATCH v2] gpio: pca953x: Add optional reset gpio control
On Tue, Jan 10, 2017 at 9:29 PM, Steve Longerbeam <slongerbeam@gmail.com> wrote:
> Add optional reset-gpios pin control. If present, de-assert the
> specified reset gpio pin to bring the chip out of reset.
>
> Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: Alexandre Courbot <gnurou@gmail.com>
> Cc: linux-gpio@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org


> --
>
> v2:
> - Specify that reset signal to PCA953x chip is active low, in
> binding doc.
> - reorder includes in gpio-pca953x.c.
> - remove dev_err() on devm_gpiod_get_optional() error return.

This should go after delimiter.

FWIW:
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>

> ---
> Documentation/devicetree/bindings/gpio/gpio-pca953x.txt | 4 ++++
> drivers/gpio/gpio-pca953x.c | 9 +++++++++
> 2 files changed, 13 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt
> index 08dd15f..e639357 100644
> --- a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt
> +++ b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt
> @@ -29,6 +29,10 @@ Required properties:
> onsemi,pca9654
> exar,xra1202
>
> +Optional properties:
> + - reset-gpios: GPIO specification for the RESET input. This is an
> + active low signal to the PCA953x.
> +
> Example:
>
>
> diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
> index d5d72d8..d44232a 100644
> --- a/drivers/gpio/gpio-pca953x.c
> +++ b/drivers/gpio/gpio-pca953x.c
> @@ -14,6 +14,7 @@
> #include <linux/module.h>
> #include <linux/init.h>
> #include <linux/gpio.h>
> +#include <linux/gpio/consumer.h>
> #include <linux/interrupt.h>
> #include <linux/i2c.h>
> #include <linux/platform_data/pca953x.h>
> @@ -754,8 +755,16 @@ static int pca953x_probe(struct i2c_client *client,
> invert = pdata->invert;
> chip->names = pdata->names;
> } else {
> + struct gpio_desc *reset_gpio;
> +
> chip->gpio_start = -1;
> irq_base = 0;
> +
> + /* See if we need to de-assert a reset pin */
> + reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
> + GPIOD_OUT_LOW);
> + if (IS_ERR(reset_gpio))
> + return PTR_ERR(reset_gpio);
> }
>
> chip->client = client;
> --
> 2.7.4
>



--
With Best Regards,
Andy Shevchenko

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