On Thursday 19 April 2007 10:48 am, David Brownell wrote:

> But after Oliver's hack, there was still:
> 
> > rndis_host 3-1:1.0: dev can't take 1558 byte packets (max 0)
> 
> And that means something else:  the device took the RNDIS
> initialization request, but didn't return a sane response.
> So it's acting as if it's not actually an RNDIS device...
> 
> 
> And then for some reason it didn't clean up correctly
> after reporting the error above ... 

Whoops, I missed the obvious reason for that.  See the
updated patch, appended.  Given this patch, it should
act more sanely ... at least in the sense that all the
fault modes around the edges behave right.

To try working around the error above, try just
commenting out the "goto fail_and_release" statement
next to the rndis_host.c line this patch adds ...
there's no guarantee it'll work though.

It can be quite surprising just how broken devices can
be when their vendors only claim MS-Windows "support"...

- Dave

========== CUT HERE
Workaround another device firmware bug, wherein CDC descriptors get
placed in a wrong place never previously observed in the wild and
where the seeming RNDIS device returns a bogus response during the
device initialization.

Signed-off-by: David Brownell <[EMAIL PROTECTED]>

---
 drivers/usb/net/cdc_ether.c  |   16 ++++++++++++++++
 drivers/usb/net/rndis_host.c |    1 +
 2 files changed, 17 insertions(+)

--- g26.orig/drivers/usb/net/cdc_ether.c        2007-02-15 18:17:21.000000000 
-0800
+++ g26/drivers/usb/net/cdc_ether.c     2007-04-19 10:27:48.000000000 -0700
@@ -91,6 +91,22 @@ int usbnet_generic_cdc_bind(struct usbne
                                "CDC descriptors on config\n");
        }
 
+       /* Maybe CDC descriptors are after the endpoint?  This bug has
+        * been seen on some 2Wire Inc RNDIS-only products.
+        */
+       if (len == 0) {
+               struct usb_host_endpoint        *hep;
+
+               hep = intf->cur_altsetting->endpoint;
+               if (hep) {
+                       buf = hep->extra;
+                       len = hep->extralen;
+               }
+               if (len)
+                       dev_dbg(&intf->dev,
+                               "CDC descriptors on endpoint\n");
+       }
+
        /* this assumes that if there's a non-RNDIS vendor variant
         * of cdc-acm, it'll fail RNDIS requests cleanly.
         */
--- g26.orig/drivers/usb/net/rndis_host.c       2007-04-17 21:38:47.000000000 
-0700
+++ g26/drivers/usb/net/rndis_host.c    2007-04-19 11:44:34.000000000 -0700
@@ -515,6 +515,7 @@ static int rndis_bind(struct usbnet *dev
                dev_err(&intf->dev,
                        "dev can't take %u byte packets (max %u)\n",
                        dev->hard_mtu, tmp);
+               retval = -EINVAL;
                goto fail_and_release;
        }
 

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