From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from cmsout01.mbox.net ([165.212.64.31]:37571 "EHLO cmsout01.mbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752027Ab1EHKat (ORCPT ); Sun, 8 May 2011 06:30:49 -0400 Message-ID: <4DC670AE.2070607@usa.net> Date: Sun, 08 May 2011 12:30:06 +0200 From: Issa Gorissen MIME-Version: 1.0 To: Andreas Oberritter CC: Martin Vidovic , Ralph Metzler , linux-media@vger.kernel.org Subject: Re: [PATCH] Ngene cam device name References: <494PeFsCj8960S01.1304706575@web01.cms.usa.net> <4DC6682C.4060907@linuxtv.org> In-Reply-To: <4DC6682C.4060907@linuxtv.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit List-ID: Sender: Mauro Carvalho Chehab On 08/05/11 11:53, Andreas Oberritter wrote: > Hello Issa, > > On 05/06/2011 08:29 PM, Issa Gorissen wrote: >> From: Andreas Oberritter >>> On 05/06/2011 03:47 PM, Issa Gorissen wrote: >>>> Also, it seems linux en50221 stack provides for the slot selection. So, >> why >>>> would you need two ca nodes ? >>> Because it's the most obvious way to use it. And more importantly >>> because the API sucks, if you have more than one device per node. You >>> can have only one reader, one writer, one poll function per node. For >>> example, you can't use one instance of mplayer to watch one channel with >>> fe0+dmx0+ca0 and a second instance of mplayer to watch or record another >>> channel with fe1+dmx1+ca0. You won't know which device has an event if >>> you use poll. The API even allows mixing multiple CI slots and built-in >>> descramblers in the same node. But try calling CA_RESET on a specific >>> slot or on a descrambler. It won't work. It's broken by design. >> >> You need to write a userspace soft which will handle the concurrent access of >> your ca device... > ... to gain what exactly over using two distinct nodes? > > How do you propose solving the problem with CA_RESET with a userspace soft? Well, solving your problem of having two mplayer instances! The CA_RESET ioctl will not reset one slot at a time obviously. But you can do an interface reset via the control register, no ? In cases when you remove/add a second/third/... module from one of the slot of a CI device, then I guess the CA_RESET is broken because it will reset everything... Have you got patches for that ? >> But for your given example, is there any card allowing you to do that (one ci >> slot, two tuners) ? > You don't seem to have understood my example. I was explaining some > drawbacks of having more than one CI slot, but only one node, answering > your prior question. > > Besides that, it's highly probable that such a card exists. It wouldn't > make much sense to hardwire CI slots to tuners, if multiple tuners exist > on a board. > > Disregarding the term "cards", there are variants of the Dreambox with > 1, 2 or 4 CI slots combined with 1 to 4 tuners. > > Regards, > Andreas I guess your point is valid, maybe the improvement you would like to see will pop up when the need will be created...