From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from casper.infradead.org ([85.118.1.10]:38707 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753376Ab1FQApJ (ORCPT ); Thu, 16 Jun 2011 20:45:09 -0400 Message-ID: <4DFAA38C.60105@infradead.org> Date: Thu, 16 Jun 2011 21:45:00 -0300 From: Mauro Carvalho Chehab MIME-Version: 1.0 To: Jonathan Corbet CC: Kassey Lee , linux-media@vger.kernel.org, g.liakhovetski@gmx.de, Kassey Lee , Daniel Drake , ytang5@marvell.com, leiwen@marvell.com, qingx@marvell.com Subject: Re: [PATCH 2/8] marvell-cam: Separate out the Marvell camera core References: <1307814409-46282-1-git-send-email-corbet@lwn.net> <1307814409-46282-3-git-send-email-corbet@lwn.net> <20110614084948.2d158323@bike.lwn.net> <20110616092726.024701c9@bike.lwn.net> In-Reply-To: <20110616092726.024701c9@bike.lwn.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit List-ID: Sender: Em 16-06-2011 12:27, Jonathan Corbet escreveu: > On Thu, 16 Jun 2011 11:12:03 +0800 > Kassey Lee wrote: > >> 2) for mcam_ctlr_stop_dma implementation, I guess you know >> something about the silicon limitation, but we found it can not pass >> our stress test(1000 times capture test, which will switch format >> between JPEG and YUV again and again). >> our solution is : >> stop the ccic controller and wait for about one frame transfer >> time, and the stop the sensor. >> this passed our stress test. for your info. > > Actually, I know very little that's not in the datasheet. Are you telling > me that there are hardware limitations that aren't documented, and that > the datasheet is not a 100% accurate description of what's going on? I'm > *shocked* I tell you! > > (For the record, with both Cafe and Armada 610, I've found the hardware to > be more reasonable and in accord with the documentation than with many > others.) > > In any case, I don't know about the limitation you're talking about here, > could you elaborate a bit? For stress testing I've run video capture for > weeks at a time, so obviously you're talking about something else. Sounds > like something I need to know? > >> 3) for videoubuf2, will you use videoubuf2 only or combined >> with soc-camera ? when can your driver for videoubuf2 ready ? > > Videobuf2 only. To be honest, I've never quite understood what soc-camera > buys. If there's a reason to do a switch, it could be contemplated - but > remember that Cafe is not an SoC device. > > The vb2 driver is working now in vmalloc mode, which is probably what Cafe > will need forever. I do plan to add dma-contig, and, probably, dma-sg > support in the very near future. If you want, I can post the vmalloc > version later today; I just want to make one more pass over it first. > >> 4) the point is: ccic and sensor driver should be independent, >> and support two CCIC controller. > > No disagreement there. I believe that two controllers should work now - > though there's probably a gotcha somewhere since it's not actually been > tried. Well, I'll be applying the patch series, as the above seems to be points for future improvements, and don't seem to prevent the addition of this patch series. Thanks, Mauro