From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sakari Ailus Subject: Re: Extended driver private controls? Date: Thu, 08 Jan 2009 17:46:50 +0200 Message-ID: <49661FEA.5020409@nokia.com> References: <494B59B5.2030800@nokia.com> <200812191548.34238.hverkuil@xs4all.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.nokia.com ([192.100.122.233]:37238 "EHLO mgw-mx06.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752457AbZAHPsr (ORCPT ); Thu, 8 Jan 2009 10:48:47 -0500 In-Reply-To: <200812191548.34238.hverkuil@xs4all.nl> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: ext Hans Verkuil Cc: v4l , "Tuukka.O Toivonen" , "linux-omap@vger.kernel.org" ext Hans Verkuil wrote: > Hi Sakari, Hello, ... > What I did to support private controls is to allow drivers to add their own > controls to the various classes, as long as the low 16 bits are >= 0x1000. > > You add them to videodev2.h (see the CX2341X private controls), and you just > pick a starting base such as 'V4L2_CTRL_CLASS_MPEG | 0x1100'. > > This way the controls are together in one header, they have unique IDs, and > you can assign them to a specific class. ... > So, to summarize: for new drivers I recommend using V4L2_CTRL_FLAG_NEXT_CTRL > and adding the private controls to videodev2.h and to prepare documentation > for inclusion with the v4l2 spec. If you really must support old apps, then > you might have to make duplicate PRIVATE_BASE controls (yuck!), but I hope > that won't be necessary. Thanks, Hans, for the definitive answer. This is what we'll do then. Cheers, -- Sakari Ailus sakari.ailus@nokia.com