net: qcom/emac: add support for emulation systems

On emulation systems, the EMAC's internal PHY ("SGMII") is not present,
but is not needed for network functionality.  So just display a warning
message and ignore the SGMII.

Tested-by: Philip Elcan <pelcan@codeaurora.org>
Tested-by: Adam Wallis <awallis@codeaurora.org>
Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
index 18c184ee1f3c0ee9e7ec66d2fafba4da22b9d676..29ba37a083722b8aec35cb57439b245f6233b9ff 100644 (file)
--- a/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
+++ b/drivers/net/ethernet/qualcomm/emac/emac-sgmii.c
@@ -297,6 +297,14 @@ static const struct of_device_id emac_sgmii_dt_match[] = {
        {}
 };
 
+/* Dummy function for systems without an internal PHY. This avoids having
+ * to check for NULL pointers before calling the functions.
+ */
+static int emac_sgmii_dummy(struct emac_adapter *adpt)
+{
+       return 0;
+}
+
 int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt)
 {
        struct platform_device *sgmii_pdev = NULL;
@@ -311,8 +319,19 @@ int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt)
                                        emac_sgmii_acpi_match);
 
                if (!dev) {
-                       dev_err(&pdev->dev, "cannot find internal phy node\n");
-                       return -ENODEV;
+                       dev_warn(&pdev->dev, "cannot find internal phy node\n");
+                       /* There is typically no internal PHY on emulation
+                        * systems, so if we can't find the node, assume
+                        * we are on an emulation system and stub-out
+                        * support for the internal PHY.  These systems only
+                        * use ACPI.
+                        */
+                       phy->open = emac_sgmii_dummy;
+                       phy->close = emac_sgmii_dummy;
+                       phy->link_up = emac_sgmii_dummy;
+                       phy->link_down = emac_sgmii_dummy;
+
+                       return 0;
                }
 
                sgmii_pdev = to_platform_device(dev);