From: Hans de Goede hdegoede@redhat.com
[ Upstream commit bdfd6ab8fdccd8b138837efff66f4a1911496378 ]
If the IRQ is already in use, then acpi_dev_gpio_irq_get_by() really should not change the type underneath the current owner.
I specifically hit an issue with this an a Chuwi Hi8 Super (CWI509) Bay Trail tablet, when the Boot OS selection in the BIOS is set to Android. In this case _STA for a MAX17047 ACPI I2C device wrongly returns 0xf and the _CRS resources for this device include a GpioInt pointing to a GPIO already in use by an _AEI handler, with a different type then specified in the _CRS for the MAX17047 device. Leading to the acpi_dev_gpio_irq_get() call done by the i2c-core-acpi.c code changing the type breaking the _AEI handler.
Now this clearly is a bug in the DSDT of this tablet (in Android mode), but in general calling irq_set_irq_type() on an IRQ which already is in use seems like a bad idea.
Signed-off-by: Hans de Goede hdegoede@redhat.com Signed-off-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpio/gpiolib-acpi.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index e3ddc99c105d4..13c6eee481da7 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -953,10 +953,17 @@ int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index) irq_flags = acpi_dev_get_irq_type(info.triggering, info.polarity);
- /* Set type if specified and different than the current one */ - if (irq_flags != IRQ_TYPE_NONE && - irq_flags != irq_get_trigger_type(irq)) - irq_set_irq_type(irq, irq_flags); + /* + * If the IRQ is not already in use then set type + * if specified and different than the current one. + */ + if (can_request_irq(irq, irq_flags)) { + if (irq_flags != IRQ_TYPE_NONE && + irq_flags != irq_get_trigger_type(irq)) + irq_set_irq_type(irq, irq_flags); + } else { + dev_dbg(&adev->dev, "IRQ %d already in use\n", irq); + }
return irq; }