usb: gadget: f_uac2: Fix incorrect setting of bNumEndpoints

Prashanth K · mehmetb0 · commit 7da2b225cbdc · 2025-02-14T15:17:08.000+03:00
BugLink: https://bugs.launchpad.net/bugs/2097298 commit 057bd54 upstream. Currently afunc_bind sets std_ac_if_desc.bNumEndpoints to 1 if controls (mute/volume) are enabled. During next afunc_bind call, bNumEndpoints would be unchanged and incorrectly set to 1 even if the controls aren't enabled. Fix this by resetting the value of bNumEndpoints to 0 on every afunc_bind call. Fixes: eaf6cbe ("usb: gadget: f_uac2: add volume and mute support") Cc: stable <stable@kernel.org> Signed-off-by: Prashanth K <quic_prashk@quicinc.com> Link: https://lore.kernel.org/r/20241211115915.159864-1-quic_prashk@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Noah Wager <noah.wager@canonical.com> Signed-off-by: Koichiro Den <koichiro.den@canonical.com>
diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
@@ -1103,6 +1103,7 @@ afunc_bind(struct usb_configuration *cfg, struct usb_function *fn)
 		uac2->as_in_alt = 0;
 	}
 
+	std_ac_if_desc.bNumEndpoints = 0;
 	if (FUOUT_EN(uac2_opts) || FUIN_EN(uac2_opts)) {
 		uac2->int_ep = usb_ep_autoconfig(gadget, &fs_ep_int_desc);
 		if (!uac2->int_ep) {

Original file line number	Diff line number	Diff line change
`@@ -1103,6 +1103,7 @@ afunc_bind(struct usb_configuration cfg, struct usb_function fn)`
`1103`	`1103`	`uac2->as_in_alt = 0;`
`1104`	`1104`	`}`
`1105`	`1105`
	`1106`	`+ std_ac_if_desc.bNumEndpoints = 0;`
`1106`	`1107`	`if (FUOUT_EN(uac2_opts) \|\| FUIN_EN(uac2_opts)) {`
`1107`	`1108`	`uac2->int_ep = usb_ep_autoconfig(gadget, &fs_ep_int_desc);`
`1108`	`1109`	`if (!uac2->int_ep) {`