From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754885Ab1GFXar (ORCPT ); Wed, 6 Jul 2011 19:30:47 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:36843 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754399Ab1GFXao (ORCPT ); Wed, 6 Jul 2011 19:30:44 -0400 From: reimth@googlemail.com To: Dave Airlie , Alex Deucher , Mario Kleiner , Jean Delvare , Tyson Whitehead , Jason Wessel Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, stable@kernel.org, Thomas Reim Subject: [PATCH 1/3] drm: Separate EDID Header Check from EDID Block Check Date: Thu, 7 Jul 2011 01:30:12 +0200 Message-Id: <1309995012-5873-4-git-send-email-reimth@gmail.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1309995012-5873-1-git-send-email-reimth@gmail.com> References: <1309995012-5873-1-git-send-email-reimth@gmail.com> In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Reim Provides function drm_edid_header_is_valid() for EDID header check and replaces EDID header check part of function drm_edid_block_valid() by a call of drm_edid_header_is_valid(). This is a prerequisite to extend DDC probing, e. g. in function radeon_ddc_probe() for Radeon devices, by a central EDID header check. Tested for kernel 2.35, 2.38 and 3.0 Signed-off-by: Thomas Reim --- drivers/gpu/drm/drm_edid.c | 24 ++++++++++++++++++------ include/drm/drm_crtc.h | 1 + 2 files changed, 19 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c index 0929219..1bbb85b 100644 --- a/drivers/gpu/drm/drm_edid.c +++ b/drivers/gpu/drm/drm_edid.c @@ -127,6 +127,23 @@ static const u8 edid_header[] = { 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00 }; + /* + * Sanity check the header of the base EDID block. Return 8 if the header + * is perfect, down to 0 if it's totally wrong. + */ +int drm_edid_header_is_valid(const u8 *raw_edid) +{ + int i, score = 0; + + for (i = 0; i < sizeof(edid_header); i++) + if (raw_edid[i] == edid_header[i]) + score++; + + return score; +} +EXPORT_SYMBOL(drm_edid_header_is_valid); + + /* * Sanity check the EDID block (base or extension). Return 0 if the block * doesn't check out, or 1 if it's valid. @@ -139,12 +156,7 @@ drm_edid_block_valid(u8 *raw_edid) struct edid *edid = (struct edid *)raw_edid; if (raw_edid[0] == 0x00) { - int score = 0; - - for (i = 0; i < sizeof(edid_header); i++) - if (raw_edid[i] == edid_header[i]) - score++; - + int score = drm_edid_header_is_valid(raw_edid); if (score == 8) ; else if (score >= 6) { DRM_DEBUG("Fixing EDID header, your hardware may be failing\n"); diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 33d12f8..0ec3687 100644 --- a/include/drm/drm_crtc.h +++ b/include/drm/drm_crtc.h @@ -802,6 +802,7 @@ extern struct drm_display_mode *drm_gtf_mode_complex(struct drm_device *dev, extern int drm_add_modes_noedid(struct drm_connector *connector, int hdisplay, int vdisplay); +extern int drm_edid_header_is_valid(const u8 *raw_edid); extern bool drm_edid_is_valid(struct edid *edid); struct drm_display_mode *drm_mode_find_dmt(struct drm_device *dev, int hsize, int vsize, int fresh); -- 1.7.1