[PATCH v3 2/4] net: stmmac: dwmac-qcom-ethqos: Mask PHY mode if configured with rgmii-id

[Yijie Yang <quic_yijiyang@xxxxxxxxxxx>]

The Qualcomm board always chooses the MAC to provide the delay instead of
the PHY, which is completely opposite to the suggestion of the Linux
kernel. The usage of phy-mode in legacy DTS was also incorrect. Change the
phy_mode passed from the DTS to the driver from PHY_INTERFACE_MODE_RGMII_ID
to PHY_INTERFACE_MODE_RGMII to ensure correct operation and adherence to
the definition.
To address the ABI compatibility issue between the kernel and DTS caused by
this change, handle the compatible string 'qcom,qcs404-evb-4000' in the
code, as it is the only legacy board that mistakenly uses the 'rgmii'
phy-mode.

Signed-off-by: Yijie Yang <quic_yijiyang@xxxxxxxxxxx>
---
 .../net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c    | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index 2a5b38723635b5ef9233ca4709e99dd5ddf06b77..e228a62723e221d58d8c4f104109e0dcf682d06d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -401,14 +401,11 @@ static int ethqos_dll_configure(struct qcom_ethqos *ethqos)
 static int ethqos_rgmii_macro_init(struct qcom_ethqos *ethqos)
 {
 	struct device *dev = &ethqos->pdev->dev;
-	int phase_shift;
+	int phase_shift = 0;
 	int loopback;
 
 	/* Determine if the PHY adds a 2 ns TX delay or the MAC handles it */
-	if (ethqos->phy_mode == PHY_INTERFACE_MODE_RGMII_ID ||
-	    ethqos->phy_mode == PHY_INTERFACE_MODE_RGMII_TXID)
-		phase_shift = 0;
-	else
+	if (ethqos->phy_mode == PHY_INTERFACE_MODE_RGMII_ID)
 		phase_shift = RGMII_CONFIG2_TX_CLK_PHASE_SHIFT_EN;
 
 	/* Disable loopback mode */
@@ -810,6 +807,17 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
 	ret = of_get_phy_mode(np, &ethqos->phy_mode);
 	if (ret)
 		return dev_err_probe(dev, ret, "Failed to get phy mode\n");
+
+	root = of_find_node_by_path("/");
+	if (root && of_device_is_compatible(root, "qcom,qcs404-evb-4000"))
+		ethqos->phy_mode = PHY_INTERFACE_MODE_RGMII_ID;
+	else if (ethqos->phy_mode == PHY_INTERFACE_MODE_RGMII)
+		return dev_err_probe(dev, -EINVAL, "Invalid phy-mode rgmii\n");
+	of_node_put(root);
+
+	if (plat_dat->phy_interface == PHY_INTERFACE_MODE_RGMII_ID)
+		plat_dat->phy_interface = PHY_INTERFACE_MODE_RGMII;
+
 	switch (ethqos->phy_mode) {
 	case PHY_INTERFACE_MODE_RGMII:
 	case PHY_INTERFACE_MODE_RGMII_ID:

-- 
2.34.1