[PATCH] net: ethernet: stmmac: dwmac-rk: Make the clk_phy could be used for external phy

[Chaoyi Chen <kernel@airkyi.com>]

From: Chaoyi Chen <chaoyi.chen@rock-chips.com>

For external phy, clk_phy should be optional, and some external phy
need the clock input from clk_phy. This patch adds support for setting
clk_phy for external phy.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: Chaoyi Chen <chaoyi.chen@rock-chips.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
index 700858ff6f7c..703b4b24f3bc 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
@@ -1558,6 +1558,7 @@ static int rk_gmac_clk_init(struct plat_stmmacenet_data *plat)
 	struct device *dev = &bsp_priv->pdev->dev;
 	int phy_iface = bsp_priv->phy_iface;
 	int i, j, ret;
+	unsigned int rate;
 
 	bsp_priv->clk_enabled = false;
 
@@ -1595,12 +1596,19 @@ static int rk_gmac_clk_init(struct plat_stmmacenet_data *plat)
 		clk_set_rate(bsp_priv->clk_mac, 50000000);
 	}
 
-	if (plat->phy_node && bsp_priv->integrated_phy) {
+	if (plat->phy_node) {
 		bsp_priv->clk_phy = of_clk_get(plat->phy_node, 0);
 		ret = PTR_ERR_OR_ZERO(bsp_priv->clk_phy);
-		if (ret)
-			return dev_err_probe(dev, ret, "Cannot get PHY clock\n");
-		clk_set_rate(bsp_priv->clk_phy, 50000000);
+		/* If it is not integrated_phy, clk_phy is optional */
+		if (bsp_priv->integrated_phy) {
+			if (ret)
+				return dev_err_probe(dev, ret, "Cannot get PHY clock\n");
+
+			ret = of_property_read_u32(plat->phy_node, "clock-frequency", &rate);
+			if (ret)
+				rate = 0;
+			clk_set_rate(bsp_priv->clk_phy, rate ? rate : 50000000);
+		}
 	}
 
 	return 0;
-- 
2.49.0