Signed-off-by: John Crispin <john@phrozen.org>
--- /dev/null
+Index: linux-4.9.47/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+===================================================================
+--- linux-4.9.47.orig/drivers/net/ethernet/mediatek/mtk_eth_soc.c
++++ linux-4.9.47/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+@@ -97,7 +97,10 @@ static int mtk_mdio_busy_wait(struct mtk
+ return 0;
+ if (time_after(jiffies, t_start + PHY_IAC_TIMEOUT))
+ break;
+- usleep_range(10, 20);
++ if (in_atomic())
++ udelay(10);
++ else
++ usleep_range(10, 20);
+ }
+
+ dev_err(eth->dev, "mdio: MDIO timeout\n");