a1 = sizeof(struct vnic_devcmd_fw_info);
 
                /* only get fw_info once and cache it */
-               err = vnic_dev_cmd(vdev, CMD_MCPU_FW_INFO, &a0, &a1, wait);
-               if (err == ERR_ECMDUNKNOWN) {
+               if (vnic_dev_capable(vdev, CMD_MCPU_FW_INFO))
+                       err = vnic_dev_cmd(vdev, CMD_MCPU_FW_INFO,
+                               &a0, &a1, wait);
+               else
                        err = vnic_dev_cmd(vdev, CMD_MCPU_FW_INFO_OLD,
                                &a0, &a1, wait);
-               }
        }
 
        *fw_info = vdev->fw_info;
 {
        u64 a0 = 0, a1 = 0;
        int wait = 1000;
-       int err;
 
-       err = vnic_dev_cmd(vdev, CMD_ENABLE_WAIT, &a0, &a1, wait);
-       if (err == ERR_ECMDUNKNOWN)
+       if (vnic_dev_capable(vdev, CMD_ENABLE_WAIT))
+               return vnic_dev_cmd(vdev, CMD_ENABLE_WAIT, &a0, &a1, wait);
+       else
                return vnic_dev_cmd(vdev, CMD_ENABLE, &a0, &a1, wait);
-
-       return err;
 }
 
 int vnic_dev_disable(struct vnic_dev *vdev)
        int wait = 1000;
        int err;
 
-       err = vnic_dev_cmd(vdev, CMD_HANG_RESET, &a0, &a1, wait);
-       if (err == ERR_ECMDUNKNOWN) {
+       if (vnic_dev_capable(vdev, CMD_HANG_RESET)) {
+               return vnic_dev_cmd(vdev, CMD_HANG_RESET,
+                               &a0, &a1, wait);
+       } else {
                err = vnic_dev_soft_reset(vdev, arg);
                if (err)
                        return err;
-
                return vnic_dev_init(vdev, 0);
        }
-
-       return err;
 }
 
 int vnic_dev_hang_reset_done(struct vnic_dev *vdev, int *done)
 
        *done = 0;
 
-       err = vnic_dev_cmd(vdev, CMD_HANG_RESET_STATUS, &a0, &a1, wait);
-       if (err) {
-               if (err == ERR_ECMDUNKNOWN)
-                       return vnic_dev_soft_reset_done(vdev, done);
-               return err;
+       if (vnic_dev_capable(vdev, CMD_HANG_RESET_STATUS)) {
+               err = vnic_dev_cmd(vdev, CMD_HANG_RESET_STATUS,
+                               &a0, &a1, wait);
+               if (err)
+                       return err;
+       } else {
+               return vnic_dev_soft_reset_done(vdev, done);
        }
 
        *done = (a0 == 0);
 {
        u64 a0 = ig_vlan_rewrite_mode, a1 = 0;
        int wait = 1000;
-       int err;
 
-       err = vnic_dev_cmd(vdev, CMD_IG_VLAN_REWRITE_MODE, &a0, &a1, wait);
-       if (err == ERR_ECMDUNKNOWN)
+       if (vnic_dev_capable(vdev, CMD_IG_VLAN_REWRITE_MODE))
+               return vnic_dev_cmd(vdev, CMD_IG_VLAN_REWRITE_MODE,
+                               &a0, &a1, wait);
+       else
                return 0;
-
-       return err;
 }
 
 static int vnic_dev_notify_setcmd(struct vnic_dev *vdev,
 
        memset(vdev->args, 0, sizeof(vdev->args));
 
-       err = _vnic_dev_cmd(vdev, CMD_INTR_COAL_CONVERT, wait);
+       if (vnic_dev_capable(vdev, CMD_INTR_COAL_CONVERT))
+               err = _vnic_dev_cmd(vdev, CMD_INTR_COAL_CONVERT, wait);
+       else
+               err = ERR_ECMDUNKNOWN;
 
        /* Use defaults when firmware doesn't support the devcmd at all or
         * supports it for only specific hardware
                return 0;
        }
 
-       vdev->intr_coal_timer_info.mul = (u32) vdev->args[0];
-       vdev->intr_coal_timer_info.div = (u32) vdev->args[1];
-       vdev->intr_coal_timer_info.max_usec = (u32) vdev->args[2];
+       if (!err) {
+               vdev->intr_coal_timer_info.mul = (u32) vdev->args[0];
+               vdev->intr_coal_timer_info.div = (u32) vdev->args[1];
+               vdev->intr_coal_timer_info.max_usec = (u32) vdev->args[2];
+       }
 
        return err;
 }