silabs: allow configuring of zero latency gpio irq

Make it possible to enable zero latency GPIO IRQ mode through
Kconfig.

Signed-off-by: Jonny Gellhaar <[email protected]>

Author: gellhaar

drivers/gpio/Kconfig.gecko

@@ -1,6 +1,7 @@
 # Gecko GPIO configuration options
 
 # Copyright (c) 2017 Christian Taedcke
+# Copyright (c) 2025 Jonny Gellhaar
 # SPDX-License-Identifier: Apache-2.0
 
 menuconfig GPIO_GECKO
@@ -15,3 +16,13 @@ config GPIO_GECKO_COMMON_INIT_PRIORITY
 	int "Common initialization priority"
 	depends on GPIO_GECKO
 	default 39
+
+config GPIO_GECKO_ZERO_LATENCY_IRQ
+	bool "Cofigure GPIO as Zephyr zero latency IRQ"
+	default n
+	depends on GPIO_GECKO
+	select ZERO_LATENCY_IRQS
+	help
+	  Make sure to read documentatino of zero latency IRQ and its
+	  implications and potential dangers. Do not call kernel API
+	  from the GPIO inerrupt callback.

drivers/gpio/gpio_gecko.c

@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2017, Christian Taedcke
+ * Copyright (c) 2025, Jonny Gellhaar
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -391,6 +392,12 @@ DEVICE_DT_DEFINE(DT_INST(0, silabs_gecko_gpio),
 		    PRE_KERNEL_1, CONFIG_GPIO_GECKO_COMMON_INIT_PRIORITY,
 		    &gpio_gecko_common_driver_api);
 
+#ifdef CONFIG_GPIO_GECKO_ZERO_LATENCY_IRQ
+#define CONFIGURED_FLAGS IRQ_ZERO_LATENCY
+#else
+#define CONFIGURED_FLAGS 0u
+#endif /* CONFIG_GPIO_GECKO_ZERO_LATENCY_IRQ */
+
 static int gpio_gecko_common_init(const struct device *dev)
 {
 #ifdef CONFIG_SOC_GECKO_DEV_INIT
@@ -400,12 +407,12 @@ static int gpio_gecko_common_init(const struct device *dev)
 	IRQ_CONNECT(GPIO_EVEN_IRQn,
 		    DT_IRQ_BY_NAME(DT_INST(0, silabs_gecko_gpio), gpio_even, priority),
 		    gpio_gecko_common_isr,
-		    DEVICE_DT_GET(DT_INST(0, silabs_gecko_gpio)), 0);
+		    DEVICE_DT_GET(DT_INST(0, silabs_gecko_gpio)), CONFIGURED_FLAGS);
 
 	IRQ_CONNECT(GPIO_ODD_IRQn,
 		    DT_IRQ_BY_NAME(DT_INST(0, silabs_gecko_gpio), gpio_odd, priority),
 		    gpio_gecko_common_isr,
-		    DEVICE_DT_GET(DT_INST(0, silabs_gecko_gpio)), 0);
+		    DEVICE_DT_GET(DT_INST(0, silabs_gecko_gpio)), CONFIGURED_FLAGS);
 
 	irq_enable(GPIO_EVEN_IRQn);
 	irq_enable(GPIO_ODD_IRQn);