Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753999AbbLIMKo (ORCPT ); Wed, 9 Dec 2015 07:10:44 -0500 Received: from mail-io0-f175.google.com ([209.85.223.175]:36683 "EHLO mail-io0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751294AbbLIMKm (ORCPT ); Wed, 9 Dec 2015 07:10:42 -0500 MIME-Version: 1.0 In-Reply-To: References: <1447526299-4222-1-git-send-email-enric.balletbo@collabora.com> <20151116115037.GF31033@ulmo.nvidia.com> <20151117125507.GD25715@ulmo.nvidia.com> <20151119115144.GA21862@ulmo.nvidia.com> Date: Wed, 9 Dec 2015 13:10:41 +0100 Message-ID: Subject: Re: [PATCH] [media] hdmi: added functions for MPEG InfoFrames From: Enric Balletbo Serra To: Thierry Reding Cc: linux-fbdev@vger.kernel.org, Jean-Christophe Plagniol-Villard , Tomi Valkeinen , Hans Verkuil , Mauro Carvalho Chehab , Martin Bugge , linux-kernel@vger.kernel.org, dri-devel Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4045 Lines: 94 Hello Thierry, 2015-11-19 13:29 GMT+01:00 Enric Balletbo Serra : > Hello Thierry, > > 2015-11-19 12:51 GMT+01:00 Thierry Reding : >> On Tue, Nov 17, 2015 at 11:55:53PM +0100, Enric Balletbo Serra wrote: >>> Hello Thierry, >>> >>> 2015-11-17 13:55 GMT+01:00 Thierry Reding : >>> > On Mon, Nov 16, 2015 at 05:28:24PM +0100, Enric Balletbo Serra wrote: >>> >> Hello Thierry, >>> >> >>> >> Many thanks for your comments. >>> >> >>> >> 2015-11-16 12:50 GMT+01:00 Thierry Reding : >>> >> > On Sat, Nov 14, 2015 at 07:38:19PM +0100, Enric Balletbo i Serra wrote: >>> >> >> The MPEG Source (MS) InfoFrame is in EIA/CEA-861B. It describes aspects of >>> >> >> the compressed video stream that were used to produce the uncompressed >>> >> >> video. >>> >> >> >>> >> >> The patch adds functions to work with MPEG InfoFrames. >>> >> >> >>> >> >> Signed-off-by: Enric Balletbo i Serra >>> >> >> --- >>> >> >> drivers/video/hdmi.c | 156 +++++++++++++++++++++++++++++++++++++++++++++++++++ >>> >> >> include/linux/hdmi.h | 24 ++++++++ >>> >> >> 2 files changed, 180 insertions(+) >>> >> > >>> >> > According to the CEA specification a source is expected to send this >>> >> > type of infoframe once per video frame. I'm curious how you envision >>> >> > this to be ensured. Would hardware provide a mechanism to store this >>> >> > data and send the infoframe automatically? How would you ensure that >>> >> > updates sent to the hardware match the upcoming frame? >>> >> > >>> >> >>> >> To be honest I'm not sure if I have the full picture. In the use case >>> >> I'm trying there is a hardware mechanism to store the data and send >>> >> the infoframe through a "Packet Send Control Register". >>> > >>> > Okay, sounds like the hardware will automatically send out packets at >>> > the right time. That still leaves open the issue of how to ensure this >>> > is synchronized with userspace. Perhaps this could be done by attaching >>> > a property to a framebuffer, so that we'd know what exact frame the meta >>> > data is attached to and when to update the FIFOs for the infoframe. >>> > >>> > Usually it's a good idea to send this type of patch as part of a larger >>> > series precisely so that people can see how it is used. That should make >>> > it easier to see if this is good enough or needs some more thought on >>> > how to synchronize. Do you have any code that you could post that makes >>> > use of this new infoframe? >>> > >>> >>> I was thinking use this and other helpers in the anx7814 bridge >>> driver[1], I thought that this patch should go through another tree, >>> this is the reason why I send it separately, but If you want or you >>> prefer I can send as part of these patch series. >>> >>> [1] https://lkml.org/lkml/2015/11/13/284 >> >> I haven't seen those patches yet. I should've been Cc'ed on those >> patches since I'm technically the maintainer of drm/bridge. Did the >> get_maintainer.pl script not list me? >> > > Mmm, just checked and yes, get_maintainer list you, so probably I did > something getting the maintainers. > Sorry. > >> In my opinion, it's usually a good idea to keep all dependencies in a >> single series, just so people get a better picture of what you're >> submitting. Of course that's just my opinion, somebody else may yell at >> you because they get Cc'ed on patches that they're not interested in... >> >> As for merging patches, it's usually best to let maintainers figure that >> out once the series is in good shape. >> >> Thierry As you suggested I included this patch series with anx7814 bridge driver series. So you can see the context. Please feel free to comment anything. https://lkml.org/lkml/2015/12/4/66 Regards, Enric -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/