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gpiolib: acpi: Make set debounce errors non fatal

PATCH RESEND In review Hans de Goede 3 participants 4 messages Oct 22, 2025 – Oct 23, 2025

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Hans de Goede

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#0 lore raw

cover gpiolib: acpi: Make set debounce errors non fatal

Hi All,

AFAICT we are all in agreement to move forward with this regression fix (1) as is. Yet I'm still not seeing this in Torvald's master branch a month after submitting this fix.

Can we please get this *regression fix* merged ASAP?

Regards,

Hans

1) https://lore.kernel.org/linux-gpio/[email protected]/

Hans de Goede (1):
gpiolib: acpi: Make set debounce errors non fatal

 drivers/gpio/gpiolib-acpi-core.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)
Signature · 1 line
2.51.0
author
#1 lore raw

PATCH RESEND 1/1 gpiolib: acpi: Make set debounce errors non fatal

Commit 16c07342b542 ("gpiolib: acpi: Program debounce when finding GPIO") adds a gpio_set_debounce_timeout() call to acpi_find_gpio() and makes acpi_find_gpio() fail if this fails.

But gpio_set_debounce_timeout() failing is a somewhat normal occurrence, since not all debounce values are supported on all GPIO/pinctrl chips.

Making this an error for example break getting the card-detect GPIO for the micro-sd slot found on many Bay Trail tablets, breaking support for the micro-sd slot on these tablets.

acpi_request_own_gpiod() already treats gpio_set_debounce_timeout() failures as non-fatal, just warning about them.

Add a acpi_gpio_set_debounce_timeout() helper which wraps gpio_set_debounce_timeout() and warns on failures and replace both existing gpio_set_debounce_timeout() calls with the helper.

Since the helper only warns on failures this fixes the card-detect issue.

Fixes 16c07342b542 ("gpiolib: acpi: Program debounce when finding GPIO")
Cc [email protected]
Cc Mario Limonciello <[email protected]>
Signed-off-by Hans de Goede <[email protected]>
---
 drivers/gpio/gpiolib-acpi-core.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)
drivers/gpio/gpiolib-acpi-core.c +15 -12
index 284e762d92c4..67c4c38afb86 100644
@@ -291,6 +291,19 @@ acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio, int polarity)
 	return GPIOD_ASIS;
 }
 
+static void acpi_gpio_set_debounce_timeout(struct gpio_desc *desc,
+					   unsigned int acpi_debounce)
+{
+	int ret;
+
+	/* ACPI uses hundredths of milliseconds units */
+	acpi_debounce *= 10;
+	ret = gpio_set_debounce_timeout(desc, acpi_debounce);
+	if (ret)
+		gpiod_warn(desc, "Failed to set debounce-timeout %u: %d\n",
+			   acpi_debounce, ret);
+}
+
 static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
 						struct acpi_resource_gpio *agpio,
 						unsigned int index,

@@ -300,18 +313,12 @@ static struct gpio_desc *acpi_request_own_gpiod(struct gpio_chip *chip,
 	enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio, polarity);
 	unsigned int pin = agpio->pin_table[index];
 	struct gpio_desc *desc;
-	int ret;
 
 	desc = gpiochip_request_own_desc(chip, pin, label, polarity, flags);
 	if (IS_ERR(desc))
 		return desc;
 
-	/* ACPI uses hundredths of milliseconds units */
-	ret = gpio_set_debounce_timeout(desc, agpio->debounce_timeout * 10);
-	if (ret)
-		dev_warn(chip->parent,
-			 "Failed to set debounce-timeout for pin 0x%04X, err %d\n",
-			 pin, ret);
+	acpi_gpio_set_debounce_timeout(desc, agpio->debounce_timeout);
 
 	return desc;
 }

@@ -944,7 +951,6 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
 	bool can_fallback = acpi_can_fallback_to_crs(adev, con_id);
 	struct acpi_gpio_info info = {};
 	struct gpio_desc *desc;
-	int ret;
 
 	desc = __acpi_find_gpio(fwnode, con_id, idx, can_fallback, &info);
 	if (IS_ERR(desc))

@@ -959,10 +965,7 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode,
 	acpi_gpio_update_gpiod_flags(dflags, &info);
 	acpi_gpio_update_gpiod_lookup_flags(lookupflags, &info);
 
-	/* ACPI uses hundredths of milliseconds units */
-	ret = gpio_set_debounce_timeout(desc, info.debounce * 10);
-	if (ret)
-		return ERR_PTR(ret);
+	acpi_gpio_set_debounce_timeout(desc, info.debounce);
 
 	return desc;
 }
Signature · 1 line
2.51.0
Acked-by on v1 1/1
#2 lore raw
Quoted 12 lines · Hans de Goede

Commit 16c07342b542 ("gpiolib: acpi: Program debounce when finding GPIO") adds a gpio_set_debounce_timeout() call to acpi_find_gpio() and makes acpi_find_gpio() fail if this fails.

But gpio_set_debounce_timeout() failing is a somewhat normal occurrence, since not all debounce values are supported on all GPIO/pinctrl chips.

Making this an error for example break getting the card-detect GPIO for the micro-sd slot found on many Bay Trail tablets, breaking support for the micro-sd slot on these tablets.

Quoted 8 lines

acpi_request_own_gpiod() already treats gpio_set_debounce_timeout() failures as non-fatal, just warning about them.

Add a acpi_gpio_set_debounce_timeout() helper which wraps gpio_set_debounce_timeout() and warns on failures and replace both existing gpio_set_debounce_timeout() calls with the helper.

Since the helper only warns on failures this fixes the card-detect issue.

Acked-by Andy Shevchenko <[email protected]>

if Bart wants to take this directly.

Signature · 2 lines
With Best Regards,
Andy Shevchenko
#3 lore raw
Quoted 16 lines · Andy Shevchenko
Quoted 15 lines · Hans de Goede

Commit 16c07342b542 ("gpiolib: acpi: Program debounce when finding GPIO") adds a gpio_set_debounce_timeout() call to acpi_find_gpio() and makes acpi_find_gpio() fail if this fails.

But gpio_set_debounce_timeout() failing is a somewhat normal occurrence, since not all debounce values are supported on all GPIO/pinctrl chips.

Making this an error for example break getting the card-detect GPIO for the micro-sd slot found on many Bay Trail tablets, breaking support for the micro-sd slot on these tablets.

acpi_request_own_gpiod() already treats gpio_set_debounce_timeout() failures as non-fatal, just warning about them.

Quoted 8 lines
Quoted 5 lines

Add a acpi_gpio_set_debounce_timeout() helper which wraps gpio_set_debounce_timeout() and warns on failures and replace both existing gpio_set_debounce_timeout() calls with the helper.

Since the helper only warns on failures this fixes the card-detect issue.

Acked-by Andy Shevchenko <[email protected]>

if Bart wants to take this directly.

Never mind, it seems we gotta fix an LKP thingy, I'm about to send a PR out of two patches.

Signature · 2 lines
With Best Regards,
Andy Shevchenko