This is a note to let you know that I've just added the patch titled
drm/i915/cnp: Properly handle VBT ddc pin out of bounds.
to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-i915-cnp-properly-handle-vbt-ddc-pin-out-of-bounds.patch
and it can be found in the queue-4.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 6e3322c226f15bc1838007f5a75566f1482b8e40 Mon Sep 17 00:00:00 2001
From: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Date: Thu, 25 Jan 2018 14:25:24 -0800
Subject: drm/i915/cnp: Properly handle VBT ddc pin out of bounds.
From: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
commit 6e3322c226f15bc1838007f5a75566f1482b8e40 upstream.
If the table result is out of bounds on the array map
there is something really wrong with VBT pin so we don't
return that vbt_pin, but only return 0 instead.
This basically reverts commit 'a8e6f3888b05 ("drm/i915/cnp:
Ignore VBT request for know invalid DDC pin.")'
Also this properly fixes commit 9c3b2689d01f ("drm/i915/cnl:
Map VBT DDC Pin to BSpec DDC Pin.")
v2: Do in a way that we don't break other platforms. (Jani)
v3: Keep debug message (Jani)
v4: Don't mess with 0 mapping was noticed by Jani and
addressed with a simple solution suggested by Lucas
that makes this even simpler.
Fixes: a8e6f3888b05 ("drm/i915/cnp: Ignore VBT request for know invalid DDC pin.")
Fixes: 9c3b2689d01f ("drm/i915/cnl: Map VBT DDC Pin to BSpec DDC Pin.")
Cc: Radhakrishna Sripada <radhakrishna.sripada@xxxxxxxxx>
Cc: Jani Nikula <jani.nikula@xxxxxxxxx>
Cc: Kai Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Suggested-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Reviewed-by: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Tested-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20180125222524.22059-1-rodrigo.vivi@xxxxxxxxx
(cherry picked from commit 3393ce1ed8fc43dbdb83952facaf04e644ca1d54)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/intel_bios.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -1107,6 +1107,7 @@ static void sanitize_aux_ch(struct drm_i
}
static const u8 cnp_ddc_pin_map[] = {
+ [0] = 0, /* N/A */
[DDC_BUS_DDI_B] = GMBUS_PIN_1_BXT,
[DDC_BUS_DDI_C] = GMBUS_PIN_2_BXT,
[DDC_BUS_DDI_D] = GMBUS_PIN_4_CNP, /* sic */
@@ -1116,9 +1117,9 @@ static const u8 cnp_ddc_pin_map[] = {
static u8 map_ddc_pin(struct drm_i915_private *dev_priv, u8 vbt_pin)
{
if (HAS_PCH_CNP(dev_priv)) {
- if (vbt_pin > 0 && vbt_pin < ARRAY_SIZE(cnp_ddc_pin_map))
+ if (vbt_pin < ARRAY_SIZE(cnp_ddc_pin_map)) {
return cnp_ddc_pin_map[vbt_pin];
- if (vbt_pin > GMBUS_PIN_4_CNP) {
+ } else {
DRM_DEBUG_KMS("Ignoring alternate pin: VBT claims DDC pin %d, which is not valid for this platform\n", vbt_pin);
return 0;
}
Patches currently in stable-queue which might be from rodrigo.vivi@xxxxxxxxx are
queue-4.15/drm-i915-cnp-properly-handle-vbt-ddc-pin-out-of-bounds.patch
queue-4.15/drm-i915-cnp-ignore-vbt-request-for-know-invalid-ddc-pin.patch