Re: [PATCH v3 -next] Input: gpio_keys: set input direction explicitly for gpio keys
flat view
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2016-11-17 01:18:42
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lkml
Subsystem:
input (keyboard, mouse, joystick, touchscreen) drivers, the rest · Maintainers:
Dmitry Torokhov, Linus Torvalds
On Wed, Nov 16, 2016 at 06:38:22PM +0000, Sudeep Holla wrote:
quoted hunk ↗ jump to hunk
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 <redacted> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Sudeep Holla <redacted> --- 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 messagediff --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 <redacted>
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 <redacted>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
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