From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932744AbcKQJsc (ORCPT ); Thu, 17 Nov 2016 04:48:32 -0500 Received: from foss.arm.com ([217.140.101.70]:46266 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751204AbcKQJs3 (ORCPT ); Thu, 17 Nov 2016 04:48:29 -0500 Subject: Re: [PATCH v3 -next] Input: gpio_keys: set input direction explicitly for gpio keys To: Dmitry Torokhov References: <1479303734-16198-1-git-send-email-sudeep.holla@arm.com> <1479321502-22265-1-git-send-email-sudeep.holla@arm.com> <20161117011836.GB8133@dtor-ws> Cc: Sudeep Holla , linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Linus Walleij , Geert Uytterhoeven , Mika Westerberg From: Sudeep Holla Organization: ARM Message-ID: Date: Thu, 17 Nov 2016 09:48:24 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161117011836.GB8133@dtor-ws> 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 17/11/16 01:18, Dmitry Torokhov wrote: > On Wed, Nov 16, 2016 at 06:38:22PM +0000, Sudeep Holla wrote: >> Commit 700a38b27eef ("Input: gpio_keys - switch to using generic device >> properties") switched to use generic device properties for GPIO keys and >> commit 5feeca3c1e39 ("Input: gpio_keys - add support for GPIO descriptors") >> switched from legacy GPIO numbers to GPIO descriptors. >> >> Previously devm_gpio_request_one was explicitly passed GPIOF_DIR_IN flag >> to set the GPIO direction as input. However devm_get_gpiod_from_child >> doesn't have such provisions and hence fwnode_get_named_gpiod can't set >> it as input. >> >> This breaks few platforms with the following error: >> " gpiochip_lock_as_irq: tried to flag a GPIO set as output for IRQ >> unable to lock HW IRQ for IRQ >> genirq: Failed to request resources for POWER (irq ) on irqchip >> gpio_keys: Unable to claim irq ; error -22 >> gpio-keys: probe failed with error -22 " >> >> This patch fixes the issue by setting input direction explicitly for >> gpio input keys. It also remove the existing GPIOF_DIR_IN flag setting >> for the legacy gpios and merges into single gpiod_direction_input call. >> >> Fixes: 700a38b27eef ("Input: gpio_keys - switch to using generic device properties") >> Cc: Dmitry Torokhov >> Cc: Linus Walleij >> Cc: Geert Uytterhoeven >> Cc: Mika Westerberg >> Signed-off-by: Sudeep Holla >> --- >> drivers/input/keyboard/gpio_keys.c | 10 +++++++++- >> drivers/input/keyboard/gpio_keys_polled.c | 10 +++++++++- >> 2 files changed, 18 insertions(+), 2 deletions(-) >> >> v2->v3: >> - Added error handling and error message >> >> diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c >> index 5576f2ae0b71..ed38a05b3039 100644 >> --- a/drivers/input/keyboard/gpio_keys.c >> +++ b/drivers/input/keyboard/gpio_keys.c >> @@ -502,7 +502,7 @@ static int gpio_keys_setup_key(struct platform_device *pdev, >> * Legacy GPIO number, so request the GPIO here and >> * convert it to descriptor. >> */ >> - unsigned flags = GPIOF_IN; >> + unsigned flags = 0; >> >> if (button->active_low) >> flags |= GPIOF_ACTIVE_LOW; > > Sudeep, I looked into this aa bit deeper, and I have issue with this > part: in absence of GPIOF_IN devm_gpio_request_one() will attempt to > configure GPIO line as output, which may not work. Because of this I > think we should move gpiod_direction_input() call into the "modern" > branch and leave legacy branch as is. > > Does the version below work for you? > Yes it does and in fact I started with something similar and then saw that I can make it common between legacy and new branch conditions. So I am fine with the modified version you sent. -- Regards, Sudeep