From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754429AbXKRV6p (ORCPT ); Sun, 18 Nov 2007 16:58:45 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752022AbXKRV6h (ORCPT ); Sun, 18 Nov 2007 16:58:37 -0500 Received: from s2.ukfsn.org ([217.158.120.143]:60638 "EHLO mail.ukfsn.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750941AbXKRV6h (ORCPT ); Sun, 18 Nov 2007 16:58:37 -0500 To: linux-kernel@vger.kernel.org Cc: Dennis Munsie , Benjamin Herrenschmidt Subject: radeonfb i2c regression post-2.6.18. From: Roger Leigh Date: Sun, 18 Nov 2007 21:58:26 +0000 Message-ID: <87lk8vxlkt.fsf@hardknott.home> User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.1 (gnu/linux) MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha1; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Transfer-Encoding: quoted-printable Hi folks, I'm using an Apple Cinema Display connected via DVI to an Apple Mac Mini with Radeon 9200 graphics. This used to work fine, but with kernels >=3D 2.6.19, the monitor powers off as soon as the framebuffer is initialised, making for a less than usable system. I've tested with 2.6.(19|2[012]), and I didn't see any related changes in 2.6.23. The breakage occured in this commit: http://git.kernel.org/?p=3Dlinux/kernel/git/torvalds/linux-2.6.git;a=3Dcomm= itdiff;h=3D7a45093b7caa9d3d5421274b4ba80fba5da17e19 Specifically, these lines: =2D /* Release the DDC lines when done or the Apple Cinema HD display =2D * will switch off =2D */ =2D OUTREG(reg, INREG(reg) & ~(VGA_DDC_CLK_OUT_EN | VGA_DDC_DATA_OUT_= EN)); =2D (void)INREG(reg); + u8 *edid =3D fb_ddc_read(&rinfo->i2c[conn-1].adapter); BenH later applied a fix: http://git.kernel.org/?p=3Dlinux/kernel/git/torvalds/linux-2.6.git;a=3Dcomm= itdiff;h=3D4f71c5de19c27f2198105d3b26b398494d5c353b but I'm not sure if this is related to the above, or was for a separate problem. Either way, the monitor is still getting powered off. Due to the code reorganisation when the i2c stuff got moved into the generic fbmon.c, I'm not sure where the workaround needs putting back (if indeed this is where the problem lies). I'm booting with video=3Dofonly to get a working system; video=3Dradeonfb:1680x1050-32@60 (with or without the additional parameters) always results in a dead monitor as soon as the framebuffer is set up. Regards, Roger =2D-=20 .''`. Roger Leigh : :' : Debian GNU/Linux http://people.debian.org/~rleigh/ `. `' Printing on GNU/Linux? http://gutenprint.sourceforge.net/ `- GPG Public Key: 0x25BFB848 Please GPG sign your mail. --=-=-= Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (GNU/Linux) iD8DBQFHQLWGVcFcaSW/uEgRAruKAKCesmaXdT/5njUd0A7S3I0Kqr1sAgCgvav0 vrNwQKghrgTTEZ4OAZKA/eU= =zYSW -----END PGP SIGNATURE----- --=-=-=--