From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S940301AbdAJTOb (ORCPT ); Tue, 10 Jan 2017 14:14:31 -0500 Received: from mail-pf0-f196.google.com ([209.85.192.196]:35978 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934584AbdAJTNN (ORCPT ); Tue, 10 Jan 2017 14:13:13 -0500 Subject: Re: [PATCH] gpio: pca953x: Add optional reset gpio control To: Vladimir Zapolskiy , linus.walleij@linaro.org, gnurou@gmail.com, robh+dt@kernel.org, mark.rutland@arm.com References: <1483391271-17304-1-git-send-email-steve_longerbeam@mentor.com> <1483391271-17304-2-git-send-email-steve_longerbeam@mentor.com> Cc: linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Steve Longerbeam From: Steve Longerbeam Message-ID: <1b85a1aa-4382-03d0-7920-4f1fdfcbda76@gmail.com> Date: Tue, 10 Jan 2017 11:13:11 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/04/2017 02:25 AM, Vladimir Zapolskiy wrote: > Hi Steve, > > On 01/02/2017 11:07 PM, Steve Longerbeam 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 >> Cc: Linus Walleij >> Cc: Alexandre Courbot >> Cc: linux-gpio@vger.kernel.org >> Cc: linux-kernel@vger.kernel.org >> --- >> Documentation/devicetree/bindings/gpio/gpio-pca953x.txt | 4 ++++ >> drivers/gpio/gpio-pca953x.c | 11 +++++++++++ >> 2 files changed, 15 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt >> index 08dd15f..da54f4c 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 >> + >> + > Drop the surplus empty line above. done. > >> Example: >> >> >> diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c >> index d5d72d8..ca2ddea 100644 >> --- a/drivers/gpio/gpio-pca953x.c >> +++ b/drivers/gpio/gpio-pca953x.c >> @@ -22,6 +22,7 @@ >> #include >> #include >> #include >> +#include >> >> #define PCA953X_INPUT 0 >> #define PCA953X_OUTPUT 1 >> @@ -754,8 +755,18 @@ 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)) { >> + dev_err(&client->dev, "request for reset pin failed\n"); > I'm not confident that the error message is wanted here, you may consider either > to remove it or at least print it out if (PTR_ERR(reset_gpio) != -EPROBE_DEFER). no problem, I just removed it. Steve