Re: [PATCH] usb: gadget: add RNDIS configfs option for Windows rndiscmp.inf compatibility

From: Krzysztof Opasiak
Date: Wed Mar 01 2017 - 03:57:27 EST




On 02/28/2017 10:58 PM, David Lechner wrote:
This adds a new configfs attribute named `use_ms_rndiscmp`. It is a
boolean value that is used to select the class/subclass/protocol used
by the RNDIS function interface association descriptor. By default,
this is 0x02 (Comm), 0x06 (Ethernet), 0xff (None). When the
use_ms_rndiscmp attribute is set to true, the values 0xef (Misc),
0x04 (RNDIS), 0x01 (Ethernet) will be used instead. This class/subclass/
protocol combination is recognized by the rndiscmp.inf file in Windows
Vista and newer and will cause Windows to load the correct RNDIS driver
without the need for a custom (signed) .inf file.


To be honest, I'm not very happy with this patch because it makes our ConfigFS interface inflexible.

Let's assume that any other combination of this attributes will be needed in a future and then what we are going to do with use_ms_rndiscmp attribute?

So instead of having single attribute which sets the whole triple of values to some hardcoded ones I would prefer to have one attribute per each of this values and allow user to set them to his own values from userspace.

Best regards,
--
Krzysztof Opasiak
Samsung R&D Institute Poland
Samsung Electronics