diff --git a/src/target/renesas.c b/src/target/renesas.c
index 11bd432..6c6128a 100644
--- a/src/target/renesas.c
+++ b/src/target/renesas.c
@@ -363,14 +363,14 @@ static uint32_t renesas_flash_size(const uint8_t *pnr)
 	}
 }
 
-static int renesas_enter_flash_mode(target *t)
+static bool renesas_enter_flash_mode(target *t)
 {
 	target_reset(t);
 
 	/* permit flash operations */
 	target_mem_write8(t, SYSC_FWEPROR, SYSC_FWEPROR_PERMIT);
 
-	return 0;
+	return true;
 }
 
 typedef enum pe_mode {
diff --git a/src/target/target_internal.h b/src/target/target_internal.h
index a9c22d3..07d7475 100644
--- a/src/target/target_internal.h
+++ b/src/target/target_internal.h
@@ -120,8 +120,8 @@ struct target_s {
 	bool (*mass_erase)(target *t);
 
 	/* Flash functions */
-	int (*enter_flash_mode)(target *t);
-	int (*exit_flash_mode)(target *t);
+	bool (*enter_flash_mode)(target *t);
+	bool (*exit_flash_mode)(target *t);
 	bool flash_mode;
 
 	/* target-defined options */