From 4b30f3e813603a9a6c334d8a25fb01a0ef342638 Mon Sep 17 00:00:00 2001
From: Animesh Manna <animesh.manna@intel.com>
Date: Fri, 23 Jul 2021 10:42:38 -0700
Subject: drm/i915/dg2: Update to bigjoiner path
Git-commit: 11955c87d209c81cec6bb7c21a2a12c4c48c4fb4
Patch-mainline: v5.15-rc1
References: jsc#SLE-22601

In verify_mpllb_state() encoder is retrieved from best_encoder
of connector_state. As there will be only one connector_state
for bigjoiner and checking encoder may not be needed for
bigjoiner-slave. This code path related to mpll is done on dg2
and need this fix to avoid null pointer dereference issue.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Manasi Navare <manasi.d.navare@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210723174239.1551352-30-matthew.d.roper@intel.com
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/display/intel_display.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index e88cf65469fc..67a803671d04 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -9215,6 +9215,9 @@ verify_mpllb_state(struct intel_atomic_state *state,
 	if (!new_crtc_state->hw.active)
 		return;
 
+	if (new_crtc_state->bigjoiner_slave)
+		return;
+
 	encoder = intel_get_crtc_new_encoder(state, new_crtc_state);
 	intel_mpllb_readout_hw_state(encoder, &mpllb_hw_state);
 
-- 
2.33.1