unsigned int irq;
 
        adbs = of_find_compatible_node(NULL, "adb", "chrp,adb0");
-       if (adbs == 0)
+       if (!adbs)
                return -ENXIO;
 
        if (of_address_to_resource(adbs, 0, &r)) {
        req->reply_len = 0;
 
        spin_lock_irqsave(&macio_lock, flags);
-       if (current_req != 0) {
+       if (current_req) {
                last_req->next = req;
                last_req = req;
        } else {
        spin_lock(&macio_lock);
        if (in_8(&adb->intr.r) & TAG) {
                handled = 1;
-               if ((req = current_req) != 0) {
+               req = current_req;
+               if (req) {
                        /* put the current request in */
                        for (i = 0; i < req->nbytes; ++i)
                                out_8(&adb->data[i].r, req->data[i]);