[ 3.5.y.z extended stable ] Patch "KMS: fix EDID detailed timing vsync parsing" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    KMS: fix EDID detailed timing vsync parsing

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 60d91bcb18bd95601132d48c97a7f08d2dd25acc Mon Sep 17 00:00:00 2001
From: Torsten Duwe <torsten at lst.de>
Date: Sat, 23 Mar 2013 15:38:22 +0100
Subject: [PATCH] KMS: fix EDID detailed timing vsync parsing

commit 16dad1d743d31a104a849c8944e6b9eb479f6cd7 upstream.

EDID spreads some values across multiple bytes; bit-fiddling is needed
to retrieve these.  The current code to parse "detailed timings" has a
cut&paste error that results in a vsync offset of at most 15 lines
instead of 63.

See

   http://en.wikipedia.org/wiki/EDID

and in the "EDID Detailed Timing Descriptor" see bytes 10+11 show why
that needs to be a left shift.

Signed-off-by: Torsten Duwe <duwe at lst.de>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
Luis Henriques <luis.henriques at canonical.com>
---
 drivers/gpu/drm/drm_edid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index 74f2421..f689958 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -876,7 +876,7 @@ static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
 	unsigned vblank = (pt->vactive_vblank_hi & 0xf) << 8 | pt->vblank_lo;
 	unsigned hsync_offset = (pt->hsync_vsync_offset_pulse_width_hi & 0xc0) << 2 | pt->hsync_offset_lo;
 	unsigned hsync_pulse_width = (pt->hsync_vsync_offset_pulse_width_hi & 0x30) << 4 | pt->hsync_pulse_width_lo;
-	unsigned vsync_offset = (pt->hsync_vsync_offset_pulse_width_hi & 0xc) >> 2 | pt->vsync_offset_pulse_width_lo >> 4;
+	unsigned vsync_offset = (pt->hsync_vsync_offset_pulse_width_hi & 0xc) << 2 | pt->vsync_offset_pulse_width_lo >> 4;
 	unsigned vsync_pulse_width = (pt->hsync_vsync_offset_pulse_width_hi & 0x3) << 4 | (pt->vsync_offset_pulse_width_lo & 0xf);

 	/* ignore tiny modes */
--
1.8.1.2