From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v3 -next] Input: gpio_keys: set input direction explicitly for gpio keys Date: Wed, 16 Nov 2016 17:18:36 -0800 Message-ID: <20161117011836.GB8133@dtor-ws> References: <1479303734-16198-1-git-send-email-sudeep.holla@arm.com> <1479321502-22265-1-git-send-email-sudeep.holla@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pg0-f66.google.com ([74.125.83.66]:36737 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752679AbcKQBSk (ORCPT ); Wed, 16 Nov 2016 20:18:40 -0500 Content-Disposition: inline In-Reply-To: <1479321502-22265-1-git-send-email-sudeep.holla@arm.com> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Sudeep Holla Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Linus Walleij , Geert Uytterhoeven , Mika Westerberg 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? Thanks! -- Dmitry Input: gpio_keys - set input direction explicitly for gpio keys From: Sudeep Holla 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 lines described by generic properties. Fixes: 700a38b27eef ("Input: gpio_keys - switch to using generic device properties") Signed-off-by: Sudeep Holla Signed-off-by: Dmitry Torokhov --- drivers/input/keyboard/gpio_keys.c | 7 +++++++ drivers/input/keyboard/gpio_keys_polled.c | 8 ++++++++ 2 files changed, 15 insertions(+) diff --git a/drivers/input/keyboard/gpio_keys.c b/drivers/input/keyboard/gpio_keys.c index 5576f2a..582462d 100644 --- a/drivers/input/keyboard/gpio_keys.c +++ b/drivers/input/keyboard/gpio_keys.c @@ -496,6 +496,13 @@ static int gpio_keys_setup_key(struct platform_device *pdev, error); return error; } + } else { + error = gpiod_direction_input(bdata->gpiod); + if (error) { + dev_err(dev, "Failed to configure GPIO %d as input: %d\n", + desc_to_gpio(bdata->gpiod), error); + return error; + } } } else if (gpio_is_valid(button->gpio)) { /* diff --git a/drivers/input/keyboard/gpio_keys_polled.c b/drivers/input/keyboard/gpio_keys_polled.c index 72b3503..bed4f20 100644 --- a/drivers/input/keyboard/gpio_keys_polled.c +++ b/drivers/input/keyboard/gpio_keys_polled.c @@ -314,6 +314,14 @@ static int gpio_keys_polled_probe(struct platform_device *pdev) fwnode_handle_put(child); return error; } + + error = gpiod_direction_input(bdata->gpiod); + if (error) { + dev_err(dev, "Failed to configure GPIO %d as input: %d\n", + desc_to_gpio(bdata->gpiod), error); + fwnode_handle_put(child); + return error; + } } else if (gpio_is_valid(button->gpio)) { /* * Legacy GPIO number so request the GPIO here and