[PATCH RFC net-next 8/9] net: stmmac: qcom-ethqos: support external PCS

[Mohd Ayaan Anwar]

Select the XPCS instance initialized by stmmac when firmware provides
a pcs-handle. Reject interfaces that are not supported by the selected
PCS.

Signed-off-by: Mohd Ayaan Anwar <mohd.anwar at oss.qualcomm.com>
---
 .../net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c  | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index ac7d6d3e205a1ab5b391def879d6f1033a0961b6..a99a78880c0fb7858e90b6212b37ebfc7fccaf84 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -7,6 +7,8 @@
 #include <linux/platform_device.h>
 #include <linux/phy.h>
 #include <linux/phy/phy.h>
+#include <linux/pcs/pcs-xpcs.h>
+#include <linux/property.h>
 
 #include "stmmac.h"
 #include "stmmac_platform.h"
@@ -681,6 +683,21 @@ static void ethqos_ptp_clk_freq_config(struct stmmac_priv *priv)
 	netdev_dbg(priv->dev, "PTP rate %lu\n", plat_dat->clk_ptp_rate);
 }
 
+static struct phylink_pcs *
+qcom_ethqos_select_pcs(struct stmmac_priv *priv, phy_interface_t interface)
+{
+	struct phylink_pcs *pcs;
+
+	if (!priv->hw->xpcs)
+		return ERR_PTR(-ENODEV);
+
+	pcs = xpcs_to_phylink_pcs(priv->hw->xpcs);
+	if (!test_bit(interface, pcs->supported_interfaces))
+		return ERR_PTR(-EOPNOTSUPP);
+
+	return pcs;
+}
+
 static int qcom_ethqos_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node;
@@ -794,6 +811,9 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
 	for (i = 1; i < plat_dat->tx_queues_to_use; i++)
 		plat_dat->tx_queues_cfg[i].tbs_en = 1;
 
+	if (fwnode_property_present(dev_fwnode(dev), "pcs-handle"))
+		plat_dat->select_pcs = qcom_ethqos_select_pcs;
+
 	return devm_stmmac_pltfr_probe(pdev, plat_dat, &stmmac_res);
 }
 

-- 
2.34.1