From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262027AbVDFILk (ORCPT ); Wed, 6 Apr 2005 04:11:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262068AbVDFILk (ORCPT ); Wed, 6 Apr 2005 04:11:40 -0400 Received: from gate.crashing.org ([63.228.1.57]:52938 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S262027AbVDFIL3 (ORCPT ); Wed, 6 Apr 2005 04:11:29 -0400 Subject: Re: Info Regarding how the Redeon driver access EDID info From: Benjamin Herrenschmidt To: karthik Cc: Linux Kernel list In-Reply-To: <200504061346.36975.karthik.r@samsung.com> References: <200504061346.36975.karthik.r@samsung.com> Content-Type: text/plain Date: Wed, 06 Apr 2005 18:10:54 +1000 Message-Id: <1112775054.9568.143.camel@gaston> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2005-04-06 at 13:46 -0700, karthik wrote: > Hi, > > I am not able to understand how the radeon video card > driver access EDID info of Monitors attached to the cards.The > driver is calling one funtion > get_property(dp, propnames[i], NULL); This is specific to PowerMacs where the EDID is stored there by the firmware. > But in this funtion its just return some value ie > dp->property->value; how this property->value field is > Initialized. Is this get_EDID is called only at boot time. how the value of > the device _node structure is initilized. > > If any have any ideas regarding this please mail me. This is all done by the firmware. radeonfb can also directly get the EDID from the monitor though via DDC2 (i2c). Look at drivers/video/aty/radeon_i2c.c and radeon_monitor.c Ben.