[net-next,PATCH 2/4] net: mdio-ipq4019: add clock support

[Robert Marko <robert.marko@xxxxxxxxxx>]

Some newer SoC-s have a separate MDIO clock that needs to be enabled.
So lets add support for handling the clocks to the driver.

Signed-off-by: Robert Marko <robert.marko@xxxxxxxxxx>
---
 drivers/net/phy/mdio-ipq4019.c | 28 +++++++++++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/net/phy/mdio-ipq4019.c b/drivers/net/phy/mdio-ipq4019.c
index 0e78830c070b..7660bf006da0 100644
--- a/drivers/net/phy/mdio-ipq4019.c
+++ b/drivers/net/phy/mdio-ipq4019.c
@@ -9,6 +9,7 @@
 #include <linux/iopoll.h>
 #include <linux/of_address.h>
 #include <linux/of_mdio.h>
+#include <linux/clk.h>
 #include <linux/phy.h>
 #include <linux/platform_device.h>
 
@@ -24,8 +25,12 @@
 #define IPQ4019_MDIO_TIMEOUT	10000
 #define IPQ4019_MDIO_SLEEP		10
 
+#define QCA_MDIO_CLK_DEFAULT_RATE	100000000
+
 struct ipq4019_mdio_data {
-	void __iomem	*membase;
+	void __iomem		*membase;
+	struct clk			*mdio_clk;
+	u32					clk_freq;
 };
 
 static int ipq4019_mdio_wait_busy(struct mii_bus *bus)
@@ -100,6 +105,7 @@ static int ipq4019_mdio_probe(struct platform_device *pdev)
 {
 	struct ipq4019_mdio_data *priv;
 	struct mii_bus *bus;
+	struct device_node *np = pdev->dev.of_node;
 	int ret;
 
 	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
@@ -112,6 +118,26 @@ static int ipq4019_mdio_probe(struct platform_device *pdev)
 	if (IS_ERR(priv->membase))
 		return PTR_ERR(priv->membase);
 
+	priv->mdio_clk = devm_clk_get_optional(&pdev->dev, "mdio_ahb");
+	if (!IS_ERR(priv->mdio_clk)) {
+		if (of_property_read_u32(np, "clock-frequency", &priv->clk_freq)) {
+			dev_warn(&pdev->dev, "Cannot find MDIO clock frequency, using default!\n");
+			priv->clk_freq = QCA_MDIO_CLK_DEFAULT_RATE;
+		}
+
+		ret = clk_set_rate(priv->mdio_clk, priv->clk_freq);
+		if (ret) {
+			dev_err(&pdev->dev, "Cannot set MDIO clock rate!\n");
+			return ret;
+		}
+
+		ret = clk_prepare_enable(priv->mdio_clk);
+		if (ret) {
+			dev_err(&pdev->dev, "Cannot enable MDIO clock!\n");
+			return ret;
+		}
+	}
+
 	bus->name = "ipq4019_mdio";
 	bus->read = ipq4019_mdio_read;
 	bus->write = ipq4019_mdio_write;
-- 
2.26.2