[PATCH net-next v3] 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>
---

Changes in v3:
- Link to V2: https://lore.kernel.org/netdev/20250812012127.197-1-kernel@airkyi.com/
- Rebase to net-next/main

Changes in v2:
- Link to V1: https://lore.kernel.org/netdev/20250806011405.115-1-kernel@airkyi.com/
- Remove get clock frequency from DT prop

 drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
index ac8288301994..5d921e62c2f5 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c
@@ -1412,12 +1412,15 @@ static int rk_gmac_clk_init(struct plat_stmmacenet_data *plat)
 		clk_set_rate(plat->stmmac_clk, 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");
+			clk_set_rate(bsp_priv->clk_phy, 50000000);
+		}
 	}
 
 	return 0;
-- 
2.49.0