From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.kapsi.fi ([217.30.184.167]:57364 "EHLO mail.kapsi.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753277Ab3FBVCt (ORCPT ); Sun, 2 Jun 2013 17:02:49 -0400 Message-ID: <51ABB2D1.6080908@iki.fi> Date: Mon, 03 Jun 2013 00:02:09 +0300 From: Antti Palosaari MIME-Version: 1.0 To: Hans Petter Selasky CC: unlisted-recipients:; linux-media@vger.kernel.org, Juergen Lock Subject: Re: TT-USB2.0 and high bitrate packet loss (DVB-C/T) References: <51A70713.6030802@bitfrost.no> <51AB385A.4040701@bitfrost.no> In-Reply-To: <51AB385A.4040701@bitfrost.no> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 06/02/2013 03:19 PM, Hans Petter Selasky wrote: > On 05/30/13 10:00, Hans Petter Selasky wrote: >> Hi there, >> >> I need to get in concat with someone that can handle, test and review a >> patch for TT-USB2.0. I've found that for certain high-bitrate streams, >> the TT-USB2.0 sends more ISOCHRONOUS MPEG data than is specified in the >> wMaxPacketSize fields. I have a USB analyzer capture which shows this >> clearly. This of course won't be received at the USB host and packet >> drops appear inside the stream. The solution is to use another alternate >> setting. The technotrend chip has many of these. I've now tested using >> alternate setting 7 instead of 3. >> >> Alternate setting 7 allows transferring a maximum of 3 * 1024 bytes. >> Alternate setting 3 allows transferring a maximum of 1 * 940 bytes. >> >> --HPS > > Hi, > > It turns out that this device, at least the version I bought, does not > work with the XHCI at all when using multi-packet transfers, alternate > setting 7, because DATA2 PID is used when transfer is less than 1024 > bytes. It should be DATA0 PID first, then 1 and 2 in the end. Probably a > firmware update can fix this, but I'm not aware about if such exists. > The PID issue was found using a USB analyzer. > > Apparently this bug has gone undetected, because at least the EHCI high > speed only controller I've got silently ignores this kind of errors and > receives the data whilst the XHCI not. Conclusion: > Existing alternate setting must be used. > > I think I will have to get another USB based receiver with CI slot. Any > recommendations for DVB-T ? There is no many alternatives available. I suspect Anysee E7 serie is the only one. And I am not even sure if its CI works anymore. Lastly when I tested it I didn't get scrambled channels working - but it could be due to card entitlements were not upgraded. Anyhow, if there is bug then it should be easy to fix. regards Antti -- http://palosaari.fi/