Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758528Ab2EIGbA (ORCPT ); Wed, 9 May 2012 02:31:00 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:39965 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755979Ab2EIGa6 (ORCPT ); Wed, 9 May 2012 02:30:58 -0400 Message-Id: <20120509055051.115608089@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Wed, 09 May 2012 06:53:05 +0100 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Daniel Vetter , Chris Wilson Subject: [ 156/167] [PATCH] drm/i915: disable sdvo hotplug on i945g/gm In-Reply-To: <20120509055029.588587017@decadent.org.uk> X-SA-Exim-Connect-IP: 192.168.4.185 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2127 Lines: 61 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Daniel Vetter commit 768b107e4b3be0acf6f58e914afe4f337c00932b upstream. Chris Wilson dug out a hw erratum saying that there's noise on the interrupt line on i945G chips. We also have a bug report from a i945GM chip with an sdvo hotplug interrupt storm (and no apparent cause). Play it safe and disable sdvo hotplug on all i945 variants. Note that this is a regression that has been introduced in 3.1, when we've enabled sdvo hotplug support with commit cc68c81aed7d892deaf12d720d5455208e94cd0a Author: Simon Farnsworth Date: Wed Sep 21 17:13:30 2011 +0100 drm/i915: Enable SDVO hotplug interrupts for HDMI and DVI Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=38442 Reported-and-tested-by: Dominik Köppl Reviewed-by: Chris Wilson Signed-Off-by: Daniel Vetter Signed-off-by: Ben Hutchings --- drivers/gpu/drm/i915/intel_sdvo.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c index 232d77d..ae5e748 100644 --- a/drivers/gpu/drm/i915/intel_sdvo.c +++ b/drivers/gpu/drm/i915/intel_sdvo.c @@ -1220,8 +1220,14 @@ static bool intel_sdvo_get_capabilities(struct intel_sdvo *intel_sdvo, struct in static int intel_sdvo_supports_hotplug(struct intel_sdvo *intel_sdvo) { + struct drm_device *dev = intel_sdvo->base.base.dev; u8 response[2]; + /* HW Erratum: SDVO Hotplug is broken on all i945G chips, there's noise + * on the line. */ + if (IS_I945G(dev) || IS_I945GM(dev)) + return false; + return intel_sdvo_get_value(intel_sdvo, SDVO_CMD_GET_HOT_PLUG_SUPPORT, &response, 2) && response[0]; } -- 1.7.10 -- 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/