Input: gpio_keys - set input direction explicitly

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 lines described by generic properties.

Fixes: 700a38b27eef ("Input: gpio_keys - switch to using generic device properties")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

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)) {
 		/*

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