From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from lists.s-osg.org ([54.187.51.154]:45466 "EHLO lists.s-osg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751472AbbFLLdr (ORCPT ); Fri, 12 Jun 2015 07:33:47 -0400 Date: Fri, 12 Jun 2015 08:33:23 -0300 From: Mauro Carvalho Chehab To: Hans Verkuil Cc: Linux Media Mailing List , Mauro Carvalho Chehab Subject: Re: [PATCH] Kconfig: disable Media Controller for DVB Message-ID: <20150612083323.79562d10@recife.lan> In-Reply-To: <557ABC28.2020101@xs4all.nl> References: <557ABC28.2020101@xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Em Fri, 12 Jun 2015 13:02:00 +0200 Hans Verkuil escreveu: > On 06/12/2015 12:57 PM, Mauro Carvalho Chehab wrote: > > Since when we start discussions about the usage Media Controller > > for complex hardware, one thing become clear: the way it is, MC > > fails to map anything more complex than a webcam. > > > > The point is that MC has entities named as devnodes, but the only > > devnode used (before the DVB patches) is MEDIA_ENT_T_DEVNODE_V4L. > > Due to the way MC got implemented, however, this entity actually > > doesn't represent the devnode, but the hardware I/O engine that > > receives data via DMA. > > > > By coincidence, such DMA is associated with the V4L device node > > on webcam hardware, but this is not true even for other V4L2 > > devices. For example, on USB hardware, the DMA is done via the > > USB controller. The data passes though a in-kernel filter that > > strips off the URB headers. Other V4L2 devices like radio may not > > even have DMA. When it have, the DMA is done via ALSA, and not > > via the V4L devnode. > > > > In other words, MC is broken as a hole, but tagging it as BROKEN > > hole -> whole > > One of these days you'll have retrained your brain for this :-) Heh ;) > > > right now would do more harm than good. > > > > So, instead, let's mark, for now, the DVB part as broken and > > block all new changes to it while we don't fix this mess, with > > "while we fix this mess, which" Changed to: "block all new changes to MC while we fix this mess, which" Sending version 2. Regards, Mauro