usb: gadget: f_uac2: Fix incorrect increment of bNumEndpoints

usb: gadget: f_uac2: Fix incorrect increment of bNumEndpoints

[Prashanth K]

Currently connect/disconnect of USB cable calls afunc_bind and
eventually increments the bNumEndpoints. And performing multiple
plugin/plugout will incorrectly increment bNumEndpoints on the
next plug-in leading to invalid configuration of descriptor and
hence enumeration failure.

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

Signed-off-by: Pratham Pratap <quic_ppratap@quicinc.com>
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
---
 drivers/usb/gadget/function/f_uac2.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c
index 08726e4..0219cd7 100644
--- 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;
 
-- 
2.7.4

Re: usb: gadget: f_uac2: Fix incorrect increment of bNumEndpoints

[Greg Kroah-Hartman]

On Wed, Nov 23, 2022 at 02:18:10PM +0530, Prashanth K wrote:
> Currently connect/disconnect of USB cable calls afunc_bind and
> eventually increments the bNumEndpoints. And performing multiple
> plugin/plugout will incorrectly increment bNumEndpoints on the
> next plug-in leading to invalid configuration of descriptor and
> hence enumeration failure.
> 
> Fix this by resetting the value of bNumEndpoints to 1 on every
> afunc_bind call.
> 
> Signed-off-by: Pratham Pratap <quic_ppratap@quicinc.com>
> Signed-off-by: Prashanth K <quic_prashk@quicinc.com>

Who authored this, Pratham or you?

And why no "[PATCH]" in the subject line?

What commit id does this fix?

thanks,

greg k-h

Re: usb: gadget: f_uac2: Fix incorrect increment of bNumEndpoints

[Prashanth K]

On 23-12-22 08:26 pm, Greg Kroah-Hartman wrote:
> On Wed, Nov 23, 2022 at 02:18:10PM +0530, Prashanth K wrote:
>> Currently connect/disconnect of USB cable calls afunc_bind and
>> eventually increments the bNumEndpoints. And performing multiple
>> plugin/plugout will incorrectly increment bNumEndpoints on the
>> next plug-in leading to invalid configuration of descriptor and
>> hence enumeration failure.
>>
>> Fix this by resetting the value of bNumEndpoints to 1 on every
>> afunc_bind call.
>>
>> Signed-off-by: Pratham Pratap <quic_ppratap@quicinc.com>
>> Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
> 
> Who authored this, Pratham or you?
>
Its authored by Pratham, but I'm upstreaming it.
> And why no "[PATCH]" in the subject line?
> 
I was under the impression that [PATCH] is not used for v1.
Will fix this in next patch

> What commit id does this fix?
> 
Will add the Fixes tag also in next patch
> thanks,
> 
> greg k-h
Thanks
Prashanth K