phy: ti: omap-usb2: fix device leak at unbind

Make sure to drop the reference to the control device taken by
of_find_device_by_node() during probe when the driver is unbound.

Fixes: 478b6c7 ("usb: phy: omap-usb2: Don't use omap_get_control_dev()")
Cc: [email protected]	# 3.13
Cc: Roger Quadros <[email protected]>
Signed-off-by: Johan Hovold <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

Author: jhovold

drivers/phy/ti/phy-omap-usb2.c

@@ -363,6 +363,13 @@ static void omap_usb2_init_errata(struct omap_usb *phy)
 		phy->flags |= OMAP_USB2_DISABLE_CHRG_DET;
 }
 
+static void omap_usb2_put_device(void *_dev)
+{
+	struct device *dev = _dev;
+
+	put_device(dev);
+}
+
 static int omap_usb2_probe(struct platform_device *pdev)
 {
 	struct omap_usb	*phy;
@@ -373,6 +380,7 @@ static int omap_usb2_probe(struct platform_device *pdev)
 	struct device_node *control_node;
 	struct platform_device *control_pdev;
 	const struct usb_phy_data *phy_data;
+	int ret;
 
 	phy_data = device_get_match_data(&pdev->dev);
 	if (!phy_data)
@@ -423,6 +431,11 @@ static int omap_usb2_probe(struct platform_device *pdev)
 			return -EINVAL;
 		}
 		phy->control_dev = &control_pdev->dev;
+
+		ret = devm_add_action_or_reset(&pdev->dev, omap_usb2_put_device,
+					       phy->control_dev);
+		if (ret)
+			return ret;
 	} else {
 		if (of_property_read_u32_index(node,
 					       "syscon-phy-power", 1,