net: designware: add clock support

This implementation manages several clocks, disable and
free all of them in case of error during probe and in remove
callback.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/drivers/net/designware.c b/drivers/net/designware.c
index 036d231..9207324 100644
--- a/drivers/net/designware.c
+++ b/drivers/net/designware.c
@@ -10,6 +10,7 @@
  */
 
 #include <common.h>
+#include <clk.h>
 #include <dm.h>
 #include <errno.h>
 #include <miiphy.h>
@@ -661,6 +662,35 @@
 	u32 iobase = pdata->iobase;
 	ulong ioaddr;
 	int ret;
+#ifdef CONFIG_CLK
+	int i, err, clock_nb;
+
+	priv->clock_count = 0;
+	clock_nb = dev_count_phandle_with_args(dev, "clocks", "#clock-cells");
+	if (clock_nb > 0) {
+		priv->clocks = devm_kcalloc(dev, clock_nb, sizeof(struct clk),
+					    GFP_KERNEL);
+		if (!priv->clocks)
+			return -ENOMEM;
+
+		for (i = 0; i < clock_nb; i++) {
+			err = clk_get_by_index(dev, i, &priv->clocks[i]);
+			if (err < 0)
+				break;
+
+			err = clk_enable(&priv->clocks[i]);
+			if (err) {
+				pr_err("failed to enable clock %d\n", i);
+				clk_free(&priv->clocks[i]);
+				goto clk_err;
+			}
+			priv->clock_count++;
+		}
+	} else if (clock_nb != -ENOENT) {
+		pr_err("failed to get clock phandle(%d)\n", clock_nb);
+		return clock_nb;
+	}
+#endif
 
 #if defined(CONFIG_DM_REGULATOR)
 	struct udevice *phy_supply;
@@ -707,6 +737,15 @@
 	debug("%s, ret=%d\n", __func__, ret);
 
 	return ret;
+
+#ifdef CONFIG_CLK
+clk_err:
+	ret = clk_release_all(priv->clocks, priv->clock_count);
+	if (ret)
+		pr_err("failed to disable all clocks\n");
+
+	return err;
+#endif
 }
 
 static int designware_eth_remove(struct udevice *dev)
@@ -717,7 +756,11 @@
 	mdio_unregister(priv->bus);
 	mdio_free(priv->bus);
 
+#ifdef CONFIG_CLK
+	return clk_release_all(priv->clocks, priv->clock_count);
+#else
 	return 0;
+#endif
 }
 
 const struct eth_ops designware_eth_ops = {