> -----Original Message----- > From: linux-usb-owner@xxxxxxxxxxxxxxx [mailto:linux-usb- > owner@xxxxxxxxxxxxxxx] On Behalf Of Pandita, Vikram > Sent: Saturday, January 09, 2010 4:21 AM > To: Matthieu CASTET > Cc: matthieu castet; linux-usb@xxxxxxxxxxxxxxx; Alan Stern > Subject: RE: [RFC] gadget ethernet dma align fix > > > > >-----Original Message----- > >From: Matthieu CASTET [mailto:matthieu.castet@xxxxxxxxxx] > >Sent: Friday, January 08, 2010 10:15 AM > >To: Pandita, Vikram > >Cc: matthieu castet; linux-usb@xxxxxxxxxxxxxxx; Alan Stern > >Subject: Re: [RFC] gadget ethernet dma align fix > > > >Hi, > > > >Pandita, Vikram a écrit : > >> Matthieu > >> > >>> -----Original Message----- > >>> From: linux-usb-owner@xxxxxxxxxxxxxxx [mailto:linux-usb- > owner@xxxxxxxxxxxxxxx] On Behalf Of > >matthieu > >>> castet > >>> Sent: Wednesday, December 23, 2009 2:11 PM > >>> To: linux-usb@xxxxxxxxxxxxxxx > >>> Cc: Alan Stern > >>> Subject: [RFC] gadget ethernet dma align fix > >>> > >>> Hi, > >>> > >>> I attach a patch that should allow to use gadget ethernet with driver > >>> not supporting dma on unaligned address. > >>> > >>> This is untested on real hardware. > >> > >> Gave a first round of test on real hardware. > >> > >> 1) patch did not compile > >> a) missing ; > >> b) a typecast was needed like: ((unsigned long)skb->data & 3) > >> c) WARN_ON() getting hit multiple times, thereby generating un- > managable amount of logs: so > >disable WARN_ON() > >That's not normal. We drop all these packets. That should explain why > >"Ping from device side hangs" is not working. > > > >What's the value of skb_headroom in this case. > >May be the check should be > >if ( (skb_headroom(skb) < ((unsigned long)skb->data & 3) )) > > Yes that's the check that was needed. > So now I have working v3 of the patch(attached) with: > a) added more comments > b) tx alignment added a gadget_dma32() check > > This works perfectly fine for ping from both sides (host/device). I also tested it on OMAP3730 EVM (based on 3630) and observed that Basic ping works (64 byte) but ping for packet size 2K fails. I tried flood ping and that also is failing. -Ajay > > Maybe we finally have a solution. > Can we get a round of review on usb list? > > Regards, > Vikram -- 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
