net: ethernet: mediatek: fix issue of driver removal with interface is up

mtk_stop() must be called to stop for freeing DMA
resources acquired and restoring state changed by mtk_open()
firstly when module removal.
Signed-off-by: NSean Wang <sean.wang@mediatek.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/mediatek/mtk_eth_soc.c

@@ -1906,6 +1906,14 @@ static int mtk_probe(struct platform_device *pdev)
 static int mtk_remove(struct platform_device *pdev)
 {
 	struct mtk_eth *eth = platform_get_drvdata(pdev);
+	int i;
+
+	/* stop all devices to make sure that dma is properly shut down */
+	for (i = 0; i < MTK_MAC_COUNT; i++) {
+		if (!eth->netdev[i])
+			continue;
+		mtk_stop(eth->netdev[i]);
+	}
 
 	clk_disable_unprepare(eth->clks[MTK_CLK_ETHIF]);
 	clk_disable_unprepare(eth->clks[MTK_CLK_ESW]);