[kernel] drm: try harder to fix bad edids

[Josh Boyer]

commit b126e8d9a5baebde99b158ab667021129a6e8e67
Author: Ben Skeggs <bskeggs at redhat.com>
Date:   Fri Dec 16 14:11:46 2011 +1000

    drm: try harder to fix bad edids

 TODO                                               |    3 +
 drm-edid-try-harder-to-fix-up-broken-headers.patch |   47 ++++++++++++++++++++
 kernel.spec                                        |    7 +++-
 3 files changed, 56 insertions(+), 1 deletions(-)
---
diff --git a/TODO b/TODO
index fef37aa..6f8ec5d 100644
--- a/TODO
+++ b/TODO
@@ -6,6 +6,9 @@
 * efi-dont-map-boot-services-on-32bit.patch
 * epoll-limit-paths.patch (in linux-next via -mm tree)
 
+**** Queued for 3.3 ***********************************************************************************
+drm-edid-try-harder-to-fix-up-broken-headers.patch
+
 **** Other stuff that should go upstream (in decreasing likelyhood) ************************************
 
 * linux-2.6-acpi-video-dos.patch
diff --git a/drm-edid-try-harder-to-fix-up-broken-headers.patch b/drm-edid-try-harder-to-fix-up-broken-headers.patch
new file mode 100644
index 0000000..26660d7
--- /dev/null
+++ b/drm-edid-try-harder-to-fix-up-broken-headers.patch
@@ -0,0 +1,47 @@
+From 115cb7ab7d3b87fe43b1fe9b05ec894b1fcfb5cf Mon Sep 17 00:00:00 2001
+From: Adam Jackson <ajax at redhat.com>
+Date: Wed, 7 Dec 2011 18:26:23 -0500
+Subject: [PATCH] drm/edid: Try harder to fix up broken headers
+
+There's no reason to force the first byte to be correct if we're already
+scoring how correct the header is.
+
+See also: https://bugzilla.redhat.com/show_bug.cgi?id=722909
+
+Signed-off-by: Adam Jackson <ajax at redhat.com>
+---
+ drivers/gpu/drm/drm_edid.c |   18 ++++++++----------
+ 1 files changed, 8 insertions(+), 10 deletions(-)
+
+diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
+index 7425e5c..8b16a49 100644
+--- a/drivers/gpu/drm/drm_edid.c
++++ b/drivers/gpu/drm/drm_edid.c
+@@ -154,16 +154,14 @@ drm_edid_block_valid(u8 *raw_edid)
+ 	int i;
+ 	u8 csum = 0;
+ 	struct edid *edid = (struct edid *)raw_edid;
+-
+-	if (raw_edid[0] == 0x00) {
+-		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");
+-			memcpy(raw_edid, edid_header, sizeof(edid_header));
+-		} else {
+-			goto bad;
+-		}
++	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");
++		memcpy(raw_edid, edid_header, sizeof(edid_header));
++	} else {
++		goto bad;
+ 	}
+ 
+ 	for (i = 0; i < EDID_LENGTH; i++)
+-- 
+1.7.7.3
+
diff --git a/kernel.spec b/kernel.spec
index b56d90f..80515d3 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -54,7 +54,7 @@ Summary: The Linux kernel
 # For non-released -rc kernels, this will be appended after the rcX and
 # gitX tags, so a 3 here would become part of release "0.rcX.gitX.3"
 #
-%global baserelease 1
+%global baserelease 2
 %global fedora_build %{baserelease}
 
 # base_sublevel is the kernel version we're starting with and patching
@@ -676,6 +676,7 @@ Patch800: linux-2.6-crash-driver.patch
 Patch1555: fix_xen_guest_on_old_EC2.patch
 
 # DRM
+Patch1700: drm-edid-try-harder-to-fix-up-broken-headers.patch
 
 # nouveau + drm fixes
 # intel drm is all merged upstream
@@ -1361,6 +1362,7 @@ ApplyPatch linux-2.6-e1000-ich9-montevina.patch
 ApplyPatch fix_xen_guest_on_old_EC2.patch
 
 # DRM core
+ApplyPatch drm-edid-try-harder-to-fix-up-broken-headers.patch
 
 # Nouveau DRM
 
@@ -2231,6 +2233,9 @@ fi
 #                 ||----w |
 #                 ||     ||
 %changelog
+* Fri Dec 16 2011 Ben Skeggs <bskeggs at redhat.com>
+- Add patch to do a better job of dealing with busted EDID headers (rhbz#751589)
+
 * Thu Dec 15 2011 Josh Boyer <jwboyer at redhat.com> - 3.2.0-0.rc5.git3.1
 - Linux 3.2-rc5-git3 (55b02d2f4445ad625213817a1736bf2884d32547)