Merge tag 'intel-gpio-v7.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/andy/linux-gpio-intel into gpio/for-current

intel-gpio for v7.1-1

* Only trigger interrupts that defined ActiveBoth in ACPI on boot

1 files changed, 15 insertions, 4 deletions

diff --git a/drivers/gpio/gpiolib-acpi-core.c b/drivers/gpio/gpiolib-acpi-core.c
index fbd6945726bf..1a762a2988b7 100644
--- a/drivers/gpio/gpiolib-acpi-core.c
+++ b/drivers/gpio/gpiolib-acpi-core.c
@@ -229,12 +229,23 @@ static void acpi_gpiochip_request_irq(struct acpi_gpio_chip *acpi_gpio,
 
 	event->irq_requested = true;
 
-	/* Make sure we trigger the initial state of edge-triggered IRQs */
+	/*
+	 * Make sure we trigger the initial state of ActiveBoth IRQs.
+	 *
+	 * According to the Microsoft GPIO documentation, triggering GPIO
+	 * interrupts marked as ActiveBoth during initialization is correct
+	 * as long as the associated GPIO line is already "asserted"
+	 * (logic level low). We should not trigger edge-based GPIO
+	 * interrupts not marked as ActiveBoth.
+	 *
+	 * See: https://learn.microsoft.com/en-us/windows-hardware/drivers/bringup/general-purpose-i-o--gpio-
+	 * Section: "GPIO controllers and ActiveBoth interrupts"
+	 */
 	if (acpi_gpio_need_run_edge_events_on_boot() &&
-	    (event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
+	    ((event->irqflags & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)) ==
+	     (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING))) {
 		value = gpiod_get_raw_value_cansleep(event->desc);
-		if (((event->irqflags & IRQF_TRIGGER_RISING) && value == 1) ||
-		    ((event->irqflags & IRQF_TRIGGER_FALLING) && value == 0))
+		if (value == 0)
 			event->handler(event->irq, event);
 	}
 }