[PATCH 4.20 03/57] usbcore: Select only first configuration for non-UAC3 compliant devices

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Saranya Gopal <saranya.gopal@xxxxxxxxx>

commit ff2a8c532c14fd22fb26a36574d9ff199afbbe54 upstream.

In most of the UAC1 and UAC2 audio devices, the first
configuration is most often the best configuration.
However, with recent patch to support UAC3 configuration,
second configuration was unintentionally chosen for
some of the UAC1/2 devices that had more than one
configuration. This was because of the existing check
after the audio config check which selected any config
which had a non-vendor class. This patch fixes this issue.

Fixes: f13912d3f014 ("usbcore: Select UAC3 configuration for audio if present")
Reported-by: Con Kolivas <kernel@xxxxxxxxxxx>
Signed-off-by: Saranya Gopal <saranya.gopal@xxxxxxxxx>
Tested-by: Con Kolivas <kernel@xxxxxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/usb/core/generic.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/usb/core/generic.c
+++ b/drivers/usb/core/generic.c
@@ -143,9 +143,12 @@ int usb_choose_configuration(struct usb_
 			continue;
 		}
 
-		if (i > 0 && desc && is_audio(desc) && is_uac3_config(desc)) {
-			best = c;
-			break;
+		if (i > 0 && desc && is_audio(desc)) {
+			if (is_uac3_config(desc)) {
+				best = c;
+				break;
+			}
+			continue;
 		}
 
 		/* From the remaining configs, choose the first one whose