find_bus_wprev
prev_bus = find_bus_wprev(parent_busno, NULL, 0);
struct bus_node *bus_cur = find_bus_wprev(pfmem->busno, NULL, 0);
return find_bus_wprev(bus_number, NULL, 0);
bus_sec = find_bus_wprev(sec_busno, NULL, 0);
bus_cur = find_bus_wprev(curr->bus_num, &bus_prev, 1);
bus_cur = find_bus_wprev(curr->bus_num, &bus_prev, 1);
bus_cur = find_bus_wprev(curr->bus_num, &bus_prev, 1);
static struct bus_node *find_bus_wprev(u8, struct bus_node **, u8);
bus_cur = find_bus_wprev(res->busno, NULL, 0);
bus_cur = find_bus_wprev(res->busno, NULL, 0);
bus_cur = find_bus_wprev(res->busno, NULL, 0);