Patch "usb: misc: uss720: check for incompatible versions of the Belkin F5U002" has been added to the 6.6-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    usb: misc: uss720: check for incompatible versions of the Belkin F5U002

to the 6.6-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     usb-misc-uss720-check-for-incompatible-versions-of-t.patch
and it can be found in the queue-6.6 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit b88b6a2284246eae78b8db1b21f66398ccc9467a
Author: Alex Henrie <alexhenrie24@xxxxxxxxx>
Date:   Tue Mar 26 09:07:11 2024 -0600

    usb: misc: uss720: check for incompatible versions of the Belkin F5U002
    
    [ Upstream commit 3295f1b866bfbcabd625511968e8a5c541f9ab32 ]
    
    The incompatible device in my possession has a sticker that says
    "F5U002 Rev 2" and "P80453-B", and lsusb identifies it as
    "050d:0002 Belkin Components IEEE-1284 Controller". There is a bug
    report from 2007 from Michael Trausch who was seeing the exact same
    errors that I saw in 2024 trying to use this cable.
    
    Link: https://lore.kernel.org/all/46DE5830.9060401@xxxxxxxxxx/
    Signed-off-by: Alex Henrie <alexhenrie24@xxxxxxxxx>
    Link: https://lore.kernel.org/r/20240326150723.99939-5-alexhenrie24@xxxxxxxxx
    Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/usb/misc/uss720.c b/drivers/usb/misc/uss720.c
index b00d92db5dfd1..eb5a8e0d9e2d6 100644
--- a/drivers/usb/misc/uss720.c
+++ b/drivers/usb/misc/uss720.c
@@ -677,7 +677,7 @@ static int uss720_probe(struct usb_interface *intf,
 	struct parport_uss720_private *priv;
 	struct parport *pp;
 	unsigned char reg;
-	int i;
+	int ret;
 
 	dev_dbg(&intf->dev, "probe: vendor id 0x%x, device id 0x%x\n",
 		le16_to_cpu(usbdev->descriptor.idVendor),
@@ -688,8 +688,8 @@ static int uss720_probe(struct usb_interface *intf,
 		usb_put_dev(usbdev);
 		return -ENODEV;
 	}
-	i = usb_set_interface(usbdev, intf->altsetting->desc.bInterfaceNumber, 2);
-	dev_dbg(&intf->dev, "set interface result %d\n", i);
+	ret = usb_set_interface(usbdev, intf->altsetting->desc.bInterfaceNumber, 2);
+	dev_dbg(&intf->dev, "set interface result %d\n", ret);
 
 	interface = intf->cur_altsetting;
 
@@ -725,12 +725,18 @@ static int uss720_probe(struct usb_interface *intf,
 	set_1284_register(pp, 7, 0x00, GFP_KERNEL);
 	set_1284_register(pp, 6, 0x30, GFP_KERNEL);  /* PS/2 mode */
 	set_1284_register(pp, 2, 0x0c, GFP_KERNEL);
-	/* debugging */
-	get_1284_register(pp, 0, &reg, GFP_KERNEL);
+
+	/* The Belkin F5U002 Rev 2 P80453-B USB parallel port adapter shares the
+	 * device ID 050d:0002 with some other device that works with this
+	 * driver, but it itself does not. Detect and handle the bad cable
+	 * here. */
+	ret = get_1284_register(pp, 0, &reg, GFP_KERNEL);
 	dev_dbg(&intf->dev, "reg: %7ph\n", priv->reg);
+	if (ret < 0)
+		return ret;
 
-	i = usb_find_last_int_in_endpoint(interface, &epd);
-	if (!i) {
+	ret = usb_find_last_int_in_endpoint(interface, &epd);
+	if (!ret) {
 		dev_dbg(&intf->dev, "epaddr %d interval %d\n",
 				epd->bEndpointAddress, epd->bInterval);
 	}