xgene: Don't fail probe, if there is no clk resource for SGMII interfaces

This change fixes following problem

[    1.827940] xgene-enet: probe of 1f210030.ethernet failed with error -2

which leads to a missing ethernet interface (reproducable at least on
Gigabyte MP30-AR0 and APM Mustang systems).

The check for a valid clk resource fails, because DT doesn't provide a
clock for sgenet1. But the driver doesn't use this clk, if the ethernet
port is connected via SGMII. Therefore this patch avoids probing for clk
on SGMII interfaces.

Fixes: 9aea7779b764 ("drivers: net: xgene: Fix crash on DT systems")
Signed-off-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/apm/xgene/xgene_enet_main.c b/drivers/net/ethernet/apm/xgene/xgene_enet_main.c
index d3906f6..86058a9 100644 (file)
--- a/drivers/net/ethernet/apm/xgene/xgene_enet_main.c
+++ b/drivers/net/ethernet/apm/xgene/xgene_enet_main.c
@@ -1785,16 +1785,18 @@ static int xgene_enet_get_resources(struct xgene_enet_pdata *pdata)
 
        xgene_enet_gpiod_get(pdata);
 
-       pdata->clk = devm_clk_get(&pdev->dev, NULL);
-       if (IS_ERR(pdata->clk)) {
-               /* Abort if the clock is defined but couldn't be retrived.
-                * Always abort if the clock is missing on DT system as
-                * the driver can't cope with this case.
-                */
-               if (PTR_ERR(pdata->clk) != -ENOENT || dev->of_node)
-                       return PTR_ERR(pdata->clk);
-               /* Firmware may have set up the clock already. */
-               dev_info(dev, "clocks have been setup already\n");
+       if (pdata->phy_mode != PHY_INTERFACE_MODE_SGMII) {
+               pdata->clk = devm_clk_get(&pdev->dev, NULL);
+               if (IS_ERR(pdata->clk)) {
+                       /* Abort if the clock is defined but couldn't be
+                        * retrived. Always abort if the clock is missing on
+                        * DT system as the driver can't cope with this case.
+                        */
+                       if (PTR_ERR(pdata->clk) != -ENOENT || dev->of_node)
+                               return PTR_ERR(pdata->clk);
+                       /* Firmware may have set up the clock already. */
+                       dev_info(dev, "clocks have been setup already\n");
+               }
        }
 
        if (pdata->phy_mode != PHY_INTERFACE_MODE_XGMII)