feat: add crc32 calculation

kernel/kmod.c

@@ -8,6 +8,7 @@
 #include <linux/kthread.h>
 #include <linux/gpio.h>
 #include <linux/delay.h>
+#include <linux/crc32.h>
 #include "../common/include/message.h"
 
 #define DEVICE_NAME "amogus"
@@ -84,21 +85,28 @@ static void send_byte(uint8_t byte) {
     }
 }
 
-static void send_data(void *data, size_t length) {
-    uint8_t *bytes = (uint8_t*)data;
+static void send_data(const void *data, size_t length) {
+    const uint8_t *bytes = (const uint8_t*)data;
 
     for (size_t i = 0; i < length; i++) {
         send_byte(bytes[i]);
     }
 }
 
+static uint32_t calculate_crc32(const void *data, size_t length){
+    return crc32(0, data, length);
+}
+
 static int timed_thread_fn(void *args) {
     while (!kthread_should_stop()) {
         wait_event_interruptible(wq, atomic_read(&wake_counter) > 0);
         atomic_dec(&wake_counter);
 
         if (slot == 0) {
+            uint32_t crc = calculate_crc32(&message, sizeof(message));
+
             send_data(&message, sizeof(message));
+            send_data(&crc, sizeof(uint32_t));
         }
 
         slot = (slot + 1) % SLOTS;