net: ethernet: stmmac: dwmac-generic: fix probe error path

BugLink: https://bugs.launchpad.net/bugs/1878232

commit 939b2002 upstream.

Make sure to call any exit() callback to undo the effect of init()
before returning on late probe errors.

Fixes: cf3f047b ("stmmac: move hw init in the probe (v2)")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ian May <ian.may@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

drivers/net/ethernet/stmicro/stmmac/dwmac-generic.c

@@ -53,7 +53,17 @@ static int dwmac_generic_probe(struct platform_device *pdev)
 			return ret;
 	}
 
-	return stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
+	ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
+	if (ret)
+		goto err_exit;
+
+	return 0;
+
+err_exit:
+	if (plat_dat->exit)
+		plat_dat->exit(pdev, plat_dat->bsp_priv);
+
+	return ret;
 }
 
 static const struct of_device_id dwmac_generic_match[] = {