net: ravb: Add clock handling support

Add support for enabling and disabling the clock using the clock
framework based on the content of OF instead of doing it manually
in the board file.
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Acked-by: NJoe Hershberger <joe.hershberger@ni.com>
Signed-off-by: NNobuhiro Iwamatsu <iwamatsu@nigauri.org>

drivers/net/ravb.c

@@ -10,6 +10,7 @@
  */
 
 #include <common.h>
+#include <clk.h>
 #include <dm.h>
 #include <errno.h>
 #include <miiphy.h>
@@ -120,6 +121,7 @@ struct ravb_priv {
 	struct phy_device	*phydev;
 	struct mii_dev		*bus;
 	void __iomem		*iobase;
+	struct clk		clk;
 };
 
 static inline void ravb_flush_dcache(u32 addr, u32 len)
@@ -432,27 +434,38 @@ int ravb_start(struct udevice *dev)
 	struct ravb_priv *eth = dev_get_priv(dev);
 	int ret;
 
-	ret = ravb_reset(dev);
+	ret = clk_enable(&eth->clk);
 	if (ret)
 		return ret;
 
+	ret = ravb_reset(dev);
+	if (ret)
+		goto err;
+
 	ravb_base_desc_init(eth);
 	ravb_tx_desc_init(eth);
 	ravb_rx_desc_init(eth);
 
 	ret = ravb_config(dev);
 	if (ret)
-		return ret;
+		goto err;
 
 	/* Setting the control will start the AVB-DMAC process. */
 	writel(CCC_OPC_OPERATION, eth->iobase + RAVB_REG_CCC);
 
 	return 0;
+
+err:
+	clk_disable(&eth->clk);
+	return ret;
 }
 
 static void ravb_stop(struct udevice *dev)
 {
+	struct ravb_priv *eth = dev_get_priv(dev);
+
 	ravb_reset(dev);
+	clk_disable(&eth->clk);
 }
 
 static int ravb_probe(struct udevice *dev)
@@ -466,6 +479,10 @@ static int ravb_probe(struct udevice *dev)
 	iobase = map_physmem(pdata->iobase, 0x1000, MAP_NOCACHE);
 	eth->iobase = iobase;
 
+	ret = clk_get_by_index(dev, 0, &eth->clk);
+	if (ret < 0)
+		goto err_mdio_alloc;
+
 	mdiodev = mdio_alloc();
 	if (!mdiodev) {
 		ret = -ENOMEM;