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

[Robert Marko]

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.ma...@sartura.hr>
---
 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