Hi all, after upgrading my development plattform from linux 2.6.21.7 on pxa25x to linux 2.6.27.3 on pxa27x I ran into problems getting a network connection over usb. I investigated some of the differences but I am still not sure, what exactly needs fixing. On my desktop I run debian kernel 2.6.29-2-686 with RNDIS support: # grep RNDIS /boot/config-2.6.29-2-686 CONFIG_USB_NET_RNDIS_WLAN=m CONFIG_USB_NET_RNDIS_HOST=m So let me describe my observations which might help fixing the problem: 2.6.21.7 gadget with RNDIS support works fine with the linux host. Configuration #1 (CDC Subset/SAFE) gets chosen 2.6.27.3 gadget without RNDIS support works fine with the linux host. 2.6.27.3 gadget with RNDIS support does not work with the linux host. Configuration #2 (RNDIS) gets chosen but I can't find a new network interface (usb0). Here comes the first question. Is the rndis configuration supposed to work with a linux host at all? Another striking difference is, that with the 2.6.21.7 gadget driver, Configuration #1 (CDC Subset/SAFE) got chosen. Investigating why this is so, I found commit 0391c828ce75cc71ae301946699a6f2d515fd99d "usb ethernet gadget: use composite gadget framework" changed bDeviceClass from 2 (Communications) to 255 (Vendor Specific Class) for devices which can't support ecm. Not being a class device, the Linux host selection algorithm simply chooses the first configuration which is RNDIS. So here comes the second question. Why was the device class changed in commit 0391c828ce75cc71ae301946699a6f2d515fd99d if 2.6.21.7 gadgets work allright as class communication devices? Alltogether can the usb ethernet gadget be turned back into a class device? Or should CDC be hardcoded to be prefered? Or should the rndis compatibility between linux host and gadget be fixed? By the way, I think linux-usb post "pxa27x_udc fails with Linux Host" [1] might be related to this problem. Thanks or your support Uli [1] http://www.spinics.net/lists/linux-usb/msg12695.html -- ------- ROAD ...the handyPC Company - - - ) ) ) Uli Luckas Head of Software Development ROAD GmbH Bennigsenstr. 14 | 12159 Berlin | Germany fon: +49 (30) 230069 - 62 | fax: +49 (30) 230069 - 69 url: www.road.de Amtsgericht Charlottenburg: HRB 96688 B Managing director: Hans-Peter Constien -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
