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authorHans de Goede <hdegoede@redhat.com>2021-11-25 23:30:10 +0300
committerAndy Shevchenko <andriy.shevchenko@linux.intel.com>2021-11-26 00:38:04 +0300
commitbdfd6ab8fdccd8b138837efff66f4a1911496378 (patch)
tree422cc0f46d414fb15c14b290d0d6505f9e122d65 /drivers/gpio/gpiolib-acpi.c
parent2ff64a84bbb3ea0281899766d9a944fd18db7013 (diff)
downloadlinux-bdfd6ab8fdccd8b138837efff66f4a1911496378.tar.xz
gpiolib: acpi: Do not set the IRQ type if the IRQ is already in use
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>
Diffstat (limited to 'drivers/gpio/gpiolib-acpi.c')
-rw-r--r--drivers/gpio/gpiolib-acpi.c15
1 files changed, 11 insertions, 4 deletions
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 7dd0484b89c6..02b06e69b50b 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -1044,10 +1044,17 @@ int acpi_dev_gpio_irq_get_by(struct acpi_device *adev, const char *name, int ind
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;
}