HIDRAW_BUFFER_SIZE
list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
list->tail = (list->tail + 1) & (HIDRAW_BUFFER_SIZE - 1);
int new_head = (list->head + 1) & (HIDRAW_BUFFER_SIZE - 1);
struct hidraw_report buffer[HIDRAW_BUFFER_SIZE];