}
 
        ret = sdw_get_id(bus);
-       if (ret) {
+       if (ret < 0) {
                dev_err(parent, "Failed to get bus id\n");
                return ret;
        }
 
        ret = sdw_master_device_add(bus, parent, fwnode);
-       if (ret) {
+       if (ret < 0) {
                dev_err(parent, "Failed to add master device at link %d\n",
                        bus->link_id);
                return ret;
        else
                ret = -ENOTSUPP; /* No ACPI/DT so error out */
 
-       if (ret) {
+       if (ret < 0) {
                dev_err(bus->dev, "Finding slaves failed:%d\n", ret);
                return ret;
        }
 
        ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                           SDW_MSG_FLAG_READ, &buf);
-       if (ret)
+       if (ret < 0)
                return ret;
 
        ret = sdw_transfer(bus, &msg);
 
        ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                           SDW_MSG_FLAG_WRITE, &value);
-       if (ret)
+       if (ret < 0)
                return ret;
 
        return sdw_transfer(bus, &msg);
 
        ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                           SDW_MSG_FLAG_READ, &buf);
-       if (ret)
+       if (ret < 0)
                return ret;
 
        ret = sdw_transfer_unlocked(bus, &msg);
 
        ret = sdw_fill_msg(&msg, NULL, addr, 1, dev_num,
                           SDW_MSG_FLAG_WRITE, &value);
-       if (ret)
+       if (ret < 0)
                return ret;
 
        return sdw_transfer_unlocked(bus, &msg);
                                 * dev_num
                                 */
                                ret = sdw_assign_device_num(slave);
-                               if (ret) {
+                               if (ret < 0) {
                                        dev_err(bus->dev,
                                                "Assign dev_num failed:%d\n",
                                                ret);
 
        ret = sdw_write_no_pm(slave, SDW_SCP_SYSTEMCTRL, val);
 
-       if (ret != 0)
+       if (ret < 0)
                dev_err(&slave->dev,
                        "Clock Stop prepare failed for slave: %d", ret);
 
        if (status[0] == SDW_SLAVE_ATTACHED) {
                dev_dbg(bus->dev, "Slave attached, programming device number\n");
                ret = sdw_program_device_num(bus);
-               if (ret)
+               if (ret < 0)
                        dev_err(bus->dev, "Slave attach failed: %d\n", ret);
                /*
                 * programming a device number will have side effects,
 
                case SDW_SLAVE_ALERT:
                        ret = sdw_handle_slave_alerts(slave);
-                       if (ret)
+                       if (ret < 0)
                                dev_err(&slave->dev,
                                        "Slave %d alert handling failed: %d\n",
                                        i, ret);
                        attached_initializing = true;
 
                        ret = sdw_initialize_slave(slave);
-                       if (ret)
+                       if (ret < 0)
                                dev_err(&slave->dev,
                                        "Slave %d initialization failed: %d\n",
                                        i, ret);
                }
 
                ret = sdw_update_slave_status(slave, status[i]);
-               if (ret)
+               if (ret < 0)
                        dev_err(&slave->dev,
                                "Update Slave status failed:%d\n", ret);
                if (attached_initializing) {