SSD130X_PAGE_HEIGHT
rect->y1 = round_down(rect->y1, SSD130X_PAGE_HEIGHT);
rect->y2 = min_t(unsigned int, round_up(rect->y2, SSD130X_PAGE_HEIGHT), ssd130x->height);
unsigned int pages = DIV_ROUND_UP(ssd130x->height, SSD130X_PAGE_HEIGHT);
unsigned int page_height = SSD130X_PAGE_HEIGHT;
unsigned int pages = DIV_ROUND_UP(ssd130x->height, SSD130X_PAGE_HEIGHT);