[PATCH 1/4] media: imon: drop redundant device references

[Johan Hovold]

Driver core holds a reference to the USB interface and its parent USB
device while the interface is bound to a driver and there is no need to
take additional references unless the structures are needed after
disconnect.

Drop the redundant device references to reduce cargo culting, make it
easier to spot drivers where extra references are needed, and reduce the
risk of memory leaks when drivers fail to release them.

Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
 drivers/media/rc/imon.c | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/drivers/media/rc/imon.c b/drivers/media/rc/imon.c
index 7e92161105d5..ecea0085d411 100644
--- a/drivers/media/rc/imon.c
+++ b/drivers/media/rc/imon.c
@@ -2250,7 +2250,7 @@ static struct imon_context *imon_init_intf0(struct usb_interface *intf,
 	mutex_lock(&ictx->lock);
 
 	ictx->dev = dev;
-	ictx->usbdev_intf0 = usb_get_dev(interface_to_usbdev(intf));
+	ictx->usbdev_intf0 = interface_to_usbdev(intf);
 	ictx->rx_urb_intf0 = rx_urb;
 	ictx->tx_urb = tx_urb;
 	ictx->rf_device = false;
@@ -2308,7 +2308,6 @@ static struct imon_context *imon_init_intf0(struct usb_interface *intf,
 	usb_kill_urb(ictx->rx_urb_intf0);
 urb_submit_failed:
 find_endpoint_failed:
-	usb_put_dev(ictx->usbdev_intf0);
 	mutex_unlock(&ictx->lock);
 	usb_free_urb(tx_urb);
 tx_urb_alloc_failed:
@@ -2338,7 +2337,7 @@ static struct imon_context *imon_init_intf1(struct usb_interface *intf,
 		timer_setup(&ictx->ttimer, imon_touch_display_timeout, 0);
 	}
 
-	ictx->usbdev_intf1 = usb_get_dev(interface_to_usbdev(intf));
+	ictx->usbdev_intf1 = interface_to_usbdev(intf);
 	ictx->rx_urb_intf1 = rx_urb;
 
 	ret = -ENODEV;
@@ -2377,7 +2376,6 @@ static struct imon_context *imon_init_intf1(struct usb_interface *intf,
 		input_unregister_device(ictx->touch);
 touch_setup_failed:
 find_endpoint_failed:
-	usb_put_dev(ictx->usbdev_intf1);
 	ictx->usbdev_intf1 = NULL;
 	mutex_unlock(&ictx->lock);
 	usb_free_urb(rx_urb);
@@ -2426,7 +2424,7 @@ static int imon_probe(struct usb_interface *interface,
 	struct imon_context *ictx = NULL;
 	u16 vendor, product;
 
-	usbdev     = usb_get_dev(interface_to_usbdev(interface));
+	usbdev     = interface_to_usbdev(interface);
 	iface_desc = interface->cur_altsetting;
 	ifnum      = iface_desc->desc.bInterfaceNumber;
 	vendor     = le16_to_cpu(usbdev->descriptor.idVendor);
@@ -2495,12 +2493,9 @@ static int imon_probe(struct usb_interface *interface,
 		 vendor, product, ifnum,
 		 usbdev->bus->busnum, usbdev->devnum);
 
-	usb_put_dev(usbdev);
-
 	return 0;
 
 fail:
-	usb_put_dev(usbdev);
 	dev_err(dev, "unable to register, err %d\n", ret);
 
 	return ret;
@@ -2550,7 +2545,6 @@ static void imon_disconnect(struct usb_interface *interface)
 			else if (ictx->display_type == IMON_DISPLAY_TYPE_VFD)
 				usb_deregister_dev(interface, &imon_vfd_class);
 		}
-		usb_put_dev(ictx->usbdev_intf0);
 	} else {
 		ictx->dev_present_intf1 = false;
 		usb_kill_urb(ictx->rx_urb_intf1);
@@ -2558,7 +2552,6 @@ static void imon_disconnect(struct usb_interface *interface)
 			timer_delete_sync(&ictx->ttimer);
 			input_unregister_device(ictx->touch);
 		}
-		usb_put_dev(ictx->usbdev_intf1);
 	}
 
 	if (refcount_dec_and_test(&ictx->users))
-- 
2.52.0