button_type
struct button_type *button_type = (void *)data;
strcpy(button_type->button_type, btn_type);
char button_type[32];
#define BUTTON_IOC_GET_TYPE _IOR('P', 1, sizeof(struct button_type))
const struct button_type *type;
static const struct button_type power_button_type = {
static const struct button_type sleep_button_type = {