usb: host: ohci-generic: add CLOCK support

use array to save enabled clocks reference in order to
disabled them in case of error during probe() or during
driver removal.

Signed-off-by: Patrice Chotard <patrice.chotard@st.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/usb/host/ohci-generic.c b/drivers/usb/host/ohci-generic.c
index f85738f..f5b27cc 100644
--- a/drivers/usb/host/ohci-generic.c
+++ b/drivers/usb/host/ohci-generic.c
@@ -5,7 +5,9 @@
  */
 
 #include <common.h>
+#include <clk.h>
 #include <dm.h>
+#include <dm/ofnode.h>
 #include "ohci.h"
 
 #if !defined(CONFIG_USB_OHCI_NEW)
@@ -14,18 +16,67 @@
 
 struct generic_ohci {
 	ohci_t ohci;
+	struct clk *clocks;	/* clock list */
+	int clock_count;	/* number of clock in clock list */
 };
 
 static int ohci_usb_probe(struct udevice *dev)
 {
 	struct ohci_regs *regs = (struct ohci_regs *)devfdt_get_addr(dev);
+	struct generic_ohci *priv = dev_get_priv(dev);
+	int i, err, ret, clock_nb;
 
-	return ohci_register(dev, regs);
+	err = 0;
+	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) {
+				error("failed to enable clock %d\n", i);
+				clk_free(&priv->clocks[i]);
+				goto clk_err;
+			}
+			priv->clock_count++;
+		}
+	} else if (clock_nb != -ENOENT) {
+		error("failed to get clock phandle(%d)\n", clock_nb);
+		return clock_nb;
+	}
+
+	err = ohci_register(dev, regs);
+	if (err)
+		goto clk_err;
+
+	return 0;
+
+clk_err:
+	ret = clk_release_all(priv->clocks, priv->clock_count);
+	if (ret)
+		error("failed to disable all clocks\n");
+
+	return err;
 }
 
 static int ohci_usb_remove(struct udevice *dev)
 {
-	return ohci_deregister(dev);
+	struct generic_ohci *priv = dev_get_priv(dev);
+	int ret;
+
+	ret = ohci_deregister(dev);
+	if (ret)
+		return ret;
+
+	return clk_release_all(priv->clocks, priv->clock_count);
 }
 
 static const struct udevice_id ohci_usb_ids[] = {