4.5.15. GPIO IRQ Test 

4.5.15.1. Test Principle

The GPIO IRQ (interrupt) function allows the system to immediately trigger an interrupt handler when the state of a GPIO pin changes (e.g., level transition), enabling rapid response to external events. Typical application scenarios include:

Button input detection.
External signal triggering (e.g., rising/falling edge).
Peripheral status feedback detection (e.g., sensor triggers).

4.5.15.2. Test Preparation

Confirm Hardware Connection
- Refer to the schematic to locate the GPIO pin, as highlighted in the yellow box in the figure below:

Device Tree Configuration

Add the gpio_keys_hobot node in the device tree and configure its properties:

 /dts-v1/;
 #include "x5.dtsi"
 #include "x5-memory.dtsi"
 #include "pinmux-func.dtsi"
 #include "pinmux-gpio.dtsi"
 #include <dt-bindings/input/linux-event-codes.h>
 #include <autoconf.h>
 / {
 	#address-cells = <2>;
 	#size-cells = <2>;

 	gpio-keys {
 		compatible = "gpio-keys";
 		autorepeat;
 		pinctrl-names = "default";
 		pinctrl-0 = <&aon_gpio_2>;

 		key-power {
 			debounce-interval = <100>;
 			gpios = <&aon_gpio_porta 2 GPIO_ACTIVE_LOW>;
 			label = "GPIO Key Power";
 			linux,code = <KEY_WAKEUP>;
 			wakeup-source;
 		};
 	};

 	gpio_keys_hobot {
 		compatible = "hobot,gpio_key";
 		debounce-interval = <200>;
 		gpios = <&ls_gpio0_porta 12 GPIO_ACTIVE_LOW>;
 		pinctrl-names = "default";
 	};

 	gua_audio_rpc_wrapper:audio-rpc-wrapper {
 		compatible = "gua,audio-rpc-wrapper";
 		rpmsg-enable;
 		status = "okay";
 	};

Debugging Tools Preparation
- cat /proc/interrupts: View the number of interrupt triggers;
- dmesg: Check driver logs and GPIO level changes;
- Dupont wires: Used to short the GPIO pin to GND for interrupt triggering tests.

4.5.15.3. Test Method

Load the Driver

Upload the compiled gpio_key_drv.ko to the board’s /userdata directory. This module is used to test GPIO IRQ functionality. For detailed usage, refer to the IRQ usage section in the document: GPIO Debug Guide.

Load the module with the following command:

root@buildroot:/userdata/gpio_irq_test# insmod gpio_key_drv.ko

Expected normal output:

[64581.388130] gpio_key_init: init
[64581.391774] gpio_key_probe: probe start

Verify that the module has been loaded:

lsmod

The output should include:

gpio_key_drv           16384  0

Test with the Driver

Use a Dupont wire to connect the target GPIO pin to GND and observe the interrupt triggering.

Check whether the interrupt count changes:

watch -n 1 "cat /proc/interrupts | grep gpio_keys_hobot"

Example output:

Every 1.0s: cat /proc/interrupts | grep gpio_keys_hobot                                                                                                                                                                                                    buildroot: Thu Jan  1 18:34:38 1970

 77:        528          0          0          0          0          0          0          0  gpio-dwapb  12 Edge      gpio_keys_hobot

Check the level change logs:

dmesg | tail

Example output:

[  217.715873] gpio_key: IRQ GPIO 391 value=0
[  218.152797] gpio_key: IRQ GPIO 391 value=1

4.5.15.4. Test Metrics

After the driver is installed, monitor the GPIO interrupt triggering via /proc/interrupts and dmesg logs, ensuring the following requirements are met:

The driver runs stably for 48 hours without kernel crashes, deadlocks, or system reboots.
The interrupt count for the relevant entry in /proc/interrupts increases normally;
dmesg prints real-time logs of GPIO level changes;
No abnormal keywords such as fail, error, or timeout appear in the logs:
```
dmesg | grep -iE 'error|fail|timeout'
```

4.5.15.5. Test Results

Check for abnormal keywords:

dmesg | grep -iE 'error|fail|timeout'

Empty output indicates normal operation with no errors.

Check interrupt count:

cat /proc/interrupts | grep gpio_keys_hobot

Example output:

 77:       28          0          0          0          0          0          0          0  gpio-dwapb  12 Edge      gpio_keys_hobot

The increasing count on interrupt number 77 indicates normal interrupt response.

Check GPIO level changes:

dmesg | tail

Partial output:

[  217.715873] gpio_key: IRQ GPIO 391 value=0
[  218.152797] gpio_key: IRQ GPIO 391 value=1
[  219.355553] gpio_key: IRQ GPIO 391 value=0
[  220.439865] gpio_key: IRQ GPIO 391 value=1
...

The continuous logging of level changes indicates timely and accurate interrupt triggering and response.