diff mbox

[v3,-next] Input: gpio_keys: set input direction explicitly for gpio keys

Message ID 1479321502-22265-1-git-send-email-sudeep.holla@arm.com
State New
Headers show

Commit Message

Sudeep Holla Nov. 16, 2016, 6:38 p.m. UTC 
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 <n> for IRQ
  genirq: Failed to request resources for POWER (irq <x>) on irqchip
  gpio_keys: Unable to claim irq <x>; 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 <dmitry.torokhov@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

---
 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

--
2.7.4

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Comments

Sudeep Holla Nov. 17, 2016, 9:48 a.m. UTC | #1 
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 <n> for IRQ

>>   genirq: Failed to request resources for POWER (irq <x>) on irqchip

>>   gpio_keys: Unable to claim irq <x>; 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 <dmitry.torokhov@gmail.com>

>> Cc: Linus Walleij <linus.walleij@linaro.org>

>> Cc: Geert Uytterhoeven <geert+renesas@glider.be>

>> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>

>> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

>> ---

>>  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
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diff mbox

Patch

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;
@@ -521,6 +521,14 @@  static int gpio_keys_setup_key(struct platform_device *pdev,
 	}

 	if (bdata->gpiod) {
+		/* set the GPIO direction to input */
+		error = gpiod_direction_input(bdata->gpiod);
+		if (error) {
+			dev_err(dev, "Failed to configure GPIO %d as input, error %d\n",
+				desc_to_gpio(bdata->gpiod), error);
+			return error;
+		}
+
 		if (button->debounce_interval) {
 			error = gpiod_set_debounce(bdata->gpiod,
 					button->debounce_interval * 1000);
diff --git a/drivers/input/keyboard/gpio_keys_polled.c b/drivers/input/keyboard/gpio_keys_polled.c
index 72b350315d43..4bd8a015cf5f 100644
--- a/drivers/input/keyboard/gpio_keys_polled.c
+++ b/drivers/input/keyboard/gpio_keys_polled.c
@@ -319,7 +319,7 @@  static int gpio_keys_polled_probe(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;
@@ -342,6 +342,14 @@  static int gpio_keys_polled_probe(struct platform_device *pdev)
 			}
 		}

+		/* set the GPIO direction to input */
+		error = gpiod_direction_input(bdata->gpiod);
+		if (error) {
+			dev_err(dev, "Failed to configure GPIO %d as input, error %d\n",
+				desc_to_gpio(bdata->gpiod), error);
+			return error;
+		}
+
 		bdata->last_state = -1;
 		bdata->threshold = DIV_ROUND_UP(button->debounce_interval,
 						pdata->poll_interval);