Hi Mario,
On 24-Jun-25 10:22 PM, Mario Limonciello wrote:
> From: Mario Limonciello <mario.limonciello@xxxxxxx>
>
> When soc-button-array looks up the GPIO to use it calls acpi_find_gpio()
> which will parse _CRS.
>
> acpi_find_gpio.cold (drivers/gpio/gpiolib-acpi-core.c:953)
> gpiod_find_and_request (drivers/gpio/gpiolib.c:4598 drivers/gpio/gpiolib.c:4625)
> gpiod_get_index (drivers/gpio/gpiolib.c:4877)
>
> The GPIO is setup basically, but the debounce information is discarded.
> The platform will assert what debounce should be in _CRS, so program it
> at the time it's available.
>
> Cc: Hans de Goede <hansg@xxxxxxxxxx>
> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx>
> ---
> drivers/gpio/gpiolib-acpi-core.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpio/gpiolib-acpi-core.c b/drivers/gpio/gpiolib-acpi-core.c
> index 12b24a717e43f..475cac2d95aa1 100644
> --- a/drivers/gpio/gpiolib-acpi-core.c
> +++ b/drivers/gpio/gpiolib-acpi-core.c
> @@ -944,6 +944,7 @@ 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))
> @@ -957,6 +958,9 @@ 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);
> + ret = gpio_set_debounce_timeout(desc, info.debounce * 10);
> + if (ret)
> + return ERR_PTR(ret);
IIRC this is going to fail sometimes, depending on which range of
debounce values the GPIO controller support. Note that there already
is another code-path in gpiolib-acpi-core.c which calls
gpio_set_debounce_timeout() in acpi_request_own_gpiod() and it does:
/* 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);
Making this a warning was done in commit cef0d022f553 ("gpiolib: acpi: Make
set-debounce-timeout failures non fatal").
Otherwise I think this is fine.
Regards,
Hans
