Since commit d24cfee7f63d ("spi: Fix acpi deferred irq probe"), the acpi_dev_gpio_irq_get() call gets delayed till spi_probe() is called on the SPI device.
If there is no driver for the SPI device then the move to spi_probe() results in acpi_dev_gpio_irq_get() never getting called. This may cause problems by leaving the GPIO pin floating because this call is responsible for setting up the GPIO pin direction and/or bias according to the values from the ACPI tables.
Re-add the removed acpi_dev_gpio_irq_get() in acpi_register_spi_device() to ensure the GPIO pin is always correctly setup, while keeping the acpi_dev_gpio_irq_get() call added to spi_probe() to deal with -EPROBE_DEFER returns caused by the GPIO controller not having a driver yet.
Link: https://bbs.archlinux.org/viewtopic.php?id=302348 Fixes: d24cfee7f63d ("spi: Fix acpi deferred irq probe") Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede hansg@kernel.org --- drivers/spi/spi.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 2e0647a06890..8588e8562220 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2851,6 +2851,16 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, acpi_set_modalias(adev, acpi_device_hid(adev), spi->modalias, sizeof(spi->modalias));
+ /* + * This gets re-tried in spi_probe() for -EPROBE_DEFER handling in case + * the GPIO controller does not have a driver yet. This needs to be done + * here too, because this call sets the GPIO direction and/or bias. + * Setting these needs to be done even if there is no driver, in which + * case spi_probe() will never get called. + */ + if (spi->irq < 0) + spi->irq = acpi_dev_gpio_irq_get(adev, 0); + acpi_device_set_enumerated(adev);
adev->power.flags.ignore_parent = true;
On Sun, Nov 02, 2025 at 08:09:21PM +0100, Hans de Goede wrote:
Since commit d24cfee7f63d ("spi: Fix acpi deferred irq probe"), the acpi_dev_gpio_irq_get() call gets delayed till spi_probe() is called on the SPI device.
If there is no driver for the SPI device then the move to spi_probe() results in acpi_dev_gpio_irq_get() never getting called. This may cause problems by leaving the GPIO pin floating because this call is responsible for setting up the GPIO pin direction and/or bias according to the values from the ACPI tables.
Re-add the removed acpi_dev_gpio_irq_get() in acpi_register_spi_device() to ensure the GPIO pin is always correctly setup, while keeping the acpi_dev_gpio_irq_get() call added to spi_probe() to deal with -EPROBE_DEFER returns caused by the GPIO controller not having a driver yet.
Even before following the link to some papering over module via the link below I wondered, if the I²C case should be covered as well. The https://github.com/alexpevzner/hotfix-kvadra-touchpad refers to I²C enabled touchpads.
...
I'm not against the SPI fix, but is it confirmed that it really fixes the issue?
Hi,
On 3-Nov-25 10:35 AM, Andy Shevchenko wrote:
On Sun, Nov 02, 2025 at 08:09:21PM +0100, Hans de Goede wrote:
Since commit d24cfee7f63d ("spi: Fix acpi deferred irq probe"), the acpi_dev_gpio_irq_get() call gets delayed till spi_probe() is called on the SPI device.
If there is no driver for the SPI device then the move to spi_probe() results in acpi_dev_gpio_irq_get() never getting called. This may cause problems by leaving the GPIO pin floating because this call is responsible for setting up the GPIO pin direction and/or bias according to the values from the ACPI tables.
Re-add the removed acpi_dev_gpio_irq_get() in acpi_register_spi_device() to ensure the GPIO pin is always correctly setup, while keeping the acpi_dev_gpio_irq_get() call added to spi_probe() to deal with -EPROBE_DEFER returns caused by the GPIO controller not having a driver yet.
Even before following the link to some papering over module via the link below I wondered, if the I²C case should be covered as well. The https://github.com/alexpevzner/hotfix-kvadra-touchpad refers to I²C enabled touchpads.
...
I'm not against the SPI fix, but is it confirmed that it really fixes the issue?
Yes Mark and I got an offlist email bisecting this to the:
Fixes: d24cfee7f63d ("spi: Fix acpi deferred irq probe")
commit (on a stable kernel series) and a later email confirming that this patch fixes it.
It seems that leaving the fingerprint reader enable pin (the first GPIO listed in _CRS which is an output only pin, is likely the enable pin) floating is causing these issues. So in a way the acpi_dev_gpio_irq_get() fixing this by forcing the enable pin to no longer float is a bit of luck. But things did work before d24cfee7f63d ("spi: Fix acpi deferred irq probe") so we need this to fix a regression and as you indicate it seems like a good idea in general and maybe we should also do this for i2c.
As for doing something similar for I2C devices, that is an interesting question. Even though it is possible I'm not aware of any i2c-devices which have a userspace driver like SPI/USB fingerprint readers do, so on i2c I would expect probe() to always get called. So I'm not sure it is necessary there.
Regards,
Hans
On Mon, Nov 03, 2025 at 10:57:44AM +0100, Hans de Goede wrote:
On 3-Nov-25 10:35 AM, Andy Shevchenko wrote:
On Sun, Nov 02, 2025 at 08:09:21PM +0100, Hans de Goede wrote:
Since commit d24cfee7f63d ("spi: Fix acpi deferred irq probe"), the acpi_dev_gpio_irq_get() call gets delayed till spi_probe() is called on the SPI device.
If there is no driver for the SPI device then the move to spi_probe() results in acpi_dev_gpio_irq_get() never getting called. This may cause problems by leaving the GPIO pin floating because this call is responsible for setting up the GPIO pin direction and/or bias according to the values from the ACPI tables.
Re-add the removed acpi_dev_gpio_irq_get() in acpi_register_spi_device() to ensure the GPIO pin is always correctly setup, while keeping the acpi_dev_gpio_irq_get() call added to spi_probe() to deal with -EPROBE_DEFER returns caused by the GPIO controller not having a driver yet.
Even before following the link to some papering over module via the link below I wondered, if the I²C case should be covered as well. The https://github.com/alexpevzner/hotfix-kvadra-touchpad refers to I²C enabled touchpads.
...
I'm not against the SPI fix, but is it confirmed that it really fixes the issue?
Yes Mark and I got an offlist email bisecting this to the:
Fixes: d24cfee7f63d ("spi: Fix acpi deferred irq probe")
commit (on a stable kernel series) and a later email confirming that this patch fixes it.
Shouldn't we use Closes in this case instead of Link?
It seems that leaving the fingerprint reader enable pin (the first GPIO listed in _CRS which is an output only pin, is likely the enable pin) floating is causing these issues. So in a way the acpi_dev_gpio_irq_get() fixing this by forcing the enable pin to no longer float is a bit of luck. But things did work before d24cfee7f63d ("spi: Fix acpi deferred irq probe") so we need this to fix a regression
Yeah, fixing a regression is good thing, but not papering over the issue.
and as you indicate it seems like a good idea in general and maybe we should also do this for i2c.
As for doing something similar for I2C devices, that is an interesting question. Even though it is possible I'm not aware of any i2c-devices which have a userspace driver like SPI/USB fingerprint readers do, so on i2c I would expect probe() to always get called. So I'm not sure it is necessary there.
Reading the problem statement (the second paragraph) I lean towards a generic solution residing somewhere in drivers/acpi/scan.c (like acpi_init_device_object() / acpi_bus_attach() calls), although I don't see a quick way how to achieve this. It seems would require a bit of refactoring to allow ACPI glue code to call specific subsystem calls or making a GPIOLIB to provide some "early" initialisation flow(s).
Hi,
On 3-Nov-25 11:13 AM, Andy Shevchenko wrote:
On Mon, Nov 03, 2025 at 10:57:44AM +0100, Hans de Goede wrote:
On 3-Nov-25 10:35 AM, Andy Shevchenko wrote:
On Sun, Nov 02, 2025 at 08:09:21PM +0100, Hans de Goede wrote:
Since commit d24cfee7f63d ("spi: Fix acpi deferred irq probe"), the acpi_dev_gpio_irq_get() call gets delayed till spi_probe() is called on the SPI device.
If there is no driver for the SPI device then the move to spi_probe() results in acpi_dev_gpio_irq_get() never getting called. This may cause problems by leaving the GPIO pin floating because this call is responsible for setting up the GPIO pin direction and/or bias according to the values from the ACPI tables.
Re-add the removed acpi_dev_gpio_irq_get() in acpi_register_spi_device() to ensure the GPIO pin is always correctly setup, while keeping the acpi_dev_gpio_irq_get() call added to spi_probe() to deal with -EPROBE_DEFER returns caused by the GPIO controller not having a driver yet.
Even before following the link to some papering over module via the link below I wondered, if the I²C case should be covered as well. The https://github.com/alexpevzner/hotfix-kvadra-touchpad refers to I²C enabled touchpads.
...
I'm not against the SPI fix, but is it confirmed that it really fixes the issue?
Yes Mark and I got an offlist email bisecting this to the:
Fixes: d24cfee7f63d ("spi: Fix acpi deferred irq probe")
commit (on a stable kernel series) and a later email confirming that this patch fixes it.
Shouldn't we use Closes in this case instead of Link?
I guess so.
It seems that leaving the fingerprint reader enable pin (the first GPIO listed in _CRS which is an output only pin, is likely the enable pin) floating is causing these issues. So in a way the acpi_dev_gpio_irq_get() fixing this by forcing the enable pin to no longer float is a bit of luck. But things did work before d24cfee7f63d ("spi: Fix acpi deferred irq probe") so we need this to fix a regression
Yeah, fixing a regression is good thing, but not papering over the issue.
I agree in principle, but this is a quick and safe way to fix the regression, where as the generic fix you describe below is likely months away and also has significant risks of causing regressions in various places, see below.
and as you indicate it seems like a good idea in general and maybe we should also do this for i2c.
As for doing something similar for I2C devices, that is an interesting question. Even though it is possible I'm not aware of any i2c-devices which have a userspace driver like SPI/USB fingerprint readers do, so on i2c I would expect probe() to always get called. So I'm not sure it is necessary there.
Reading the problem statement (the second paragraph) I lean towards a generic solution residing somewhere in drivers/acpi/scan.c (like acpi_init_device_object() / acpi_bus_attach() calls), although I don't see a quick way how to achieve this. It seems would require a bit of refactoring to allow ACPI glue code to call specific subsystem calls or making a GPIOLIB to provide some "early" initialisation flow(s).
I guess that you want to do the direction and bias init on all GPIOs listed in _CRS, at least for devices with status == present ?
I was wondering about the same thing, but ACPI tables are full of, well, erm, garbage in various places so I'm afraid that doing this for all GPIO _CRS resources is likely to cause a whole lot of pain.
Typically the firmware already sets up the direction + bias of all used pins. I'm pretty sure the BIOS-es have some GPIO init table especially for this somewhere.
Now those init-tables may have bugs, but I'm seriously worried about the implication of doing the direction + bios setup for all _CRS GPIO entries. I have simply seen too much non sense devices (with _STA returning 0x0f) listing GPIOs also actually used elsewhere to think this is a good idea.
Regards,
Hans
On Mon, Nov 03, 2025 at 11:20:30AM +0100, Hans de Goede wrote:
On 3-Nov-25 11:13 AM, Andy Shevchenko wrote:
On Mon, Nov 03, 2025 at 10:57:44AM +0100, Hans de Goede wrote:
On 3-Nov-25 10:35 AM, Andy Shevchenko wrote:
On Sun, Nov 02, 2025 at 08:09:21PM +0100, Hans de Goede wrote:
Since commit d24cfee7f63d ("spi: Fix acpi deferred irq probe"), the acpi_dev_gpio_irq_get() call gets delayed till spi_probe() is called on the SPI device.
If there is no driver for the SPI device then the move to spi_probe() results in acpi_dev_gpio_irq_get() never getting called. This may cause problems by leaving the GPIO pin floating because this call is responsible for setting up the GPIO pin direction and/or bias according to the values from the ACPI tables.
Re-add the removed acpi_dev_gpio_irq_get() in acpi_register_spi_device() to ensure the GPIO pin is always correctly setup, while keeping the acpi_dev_gpio_irq_get() call added to spi_probe() to deal with -EPROBE_DEFER returns caused by the GPIO controller not having a driver yet.
Even before following the link to some papering over module via the link below I wondered, if the I²C case should be covered as well. The https://github.com/alexpevzner/hotfix-kvadra-touchpad refers to I²C enabled touchpads.
...
I'm not against the SPI fix, but is it confirmed that it really fixes the issue?
Yes Mark and I got an offlist email bisecting this to the:
Fixes: d24cfee7f63d ("spi: Fix acpi deferred irq probe")
commit (on a stable kernel series) and a later email confirming that this patch fixes it.
Shouldn't we use Closes in this case instead of Link?
I guess so.
It seems that leaving the fingerprint reader enable pin (the first GPIO listed in _CRS which is an output only pin, is likely the enable pin) floating is causing these issues. So in a way the acpi_dev_gpio_irq_get() fixing this by forcing the enable pin to no longer float is a bit of luck. But things did work before d24cfee7f63d ("spi: Fix acpi deferred irq probe") so we need this to fix a regression
Yeah, fixing a regression is good thing, but not papering over the issue.
I agree in principle, but this is a quick and safe way to fix the regression, where as the generic fix you describe below is likely months away and also has significant risks of causing regressions in various places, see below.
Perhaps we should add a TODO / FIXME there as well? So at least we will know that this is not a proper solution.
and as you indicate it seems like a good idea in general and maybe we should also do this for i2c.
As for doing something similar for I2C devices, that is an interesting question. Even though it is possible I'm not aware of any i2c-devices which have a userspace driver like SPI/USB fingerprint readers do, so on i2c I would expect probe() to always get called. So I'm not sure it is necessary there.
Reading the problem statement (the second paragraph) I lean towards a generic solution residing somewhere in drivers/acpi/scan.c (like acpi_init_device_object() / acpi_bus_attach() calls), although I don't see a quick way how to achieve this. It seems would require a bit of refactoring to allow ACPI glue code to call specific subsystem calls or making a GPIOLIB to provide some "early" initialisation flow(s).
I guess that you want to do the direction and bias init on all GPIOs listed in _CRS, at least for devices with status == present ?
For the devices that are serial busses only (I²C, SPI, UART).
I was wondering about the same thing, but ACPI tables are full of, well, erm, garbage in various places so I'm afraid that doing this for all GPIO _CRS resources is likely to cause a whole lot of pain.
Typically the firmware already sets up the direction + bias of all used pins. I'm pretty sure the BIOS-es have some GPIO init table especially for this somewhere.
Now those init-tables may have bugs, but I'm seriously worried about the implication of doing the direction + bios setup for all _CRS GPIO entries. I have simply seen too much non sense devices (with _STA returning 0x0f) listing GPIOs also actually used elsewhere to think this is a good idea.
Btw, other GPIO initialisation issues we have been solving by adding quirks. Why this one can't be targeted with the same approach?
linux-stable-mirror@lists.linaro.org
-
Andy Shevchenko -
Hans de Goede