usb: gadget: f_uac2: Fix incorrect increment of bNumEndpoints

commit 2fa89458af9993fab8054daf827f38881e2ad473 upstream.

Currently connect/disconnect of USB cable calls afunc_bind and
eventually increments the bNumEndpoints. Performing multiple
plugin/plugout will increment bNumEndpoints incorrectly, and on
the next plug-in it leads to invalid configuration of descriptor
and hence enumeration fails.

Fix this by resetting the value of bNumEndpoints to 1 on every
afunc_bind call.

Fixes: 40c73b30546e ("usb: gadget: f_uac2: add adaptive sync support for capture")
Cc: stable <stable@kernel.org>
Signed-off-by: Pratham Pratap <quic_ppratap@quicinc.com>
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Link: https://lore.kernel.org/r/1674631645-28888-1-git-send-email-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 08726e4..0219cd7 100644 (file)
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -1142,6 +1142,7 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
                }
                std_as_out_if0_desc.bInterfaceNumber = ret;
                std_as_out_if1_desc.bInterfaceNumber = ret;
+               std_as_out_if1_desc.bNumEndpoints = 1;
                uac2->as_out_intf = ret;
                uac2->as_out_alt = 0;