From cfe7f3a5d42c854985511682dada8551edcd0aa9 Mon Sep 17 00:00:00 2001
From: Vandita Kulkarni <vandita.kulkarni@intel.com>
Date: Tue, 19 Nov 2019 12:50:04 +0530
Subject: drm/i915/dsi: Do not read the transcoder register.
Git-commit: 6d73af2767bb4855a3761a602c6cdde62640a185
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322

As per the Bspec, port mapping is fixed for mipi dsi.

v2: Reuse the existing function (Jani)

Signed-off-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191119072004.4093-1-vandita.kulkarni@intel.com
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/display/intel_display.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 699b98f8a6d2..e909328fc5ac 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -10572,16 +10572,21 @@ static void haswell_get_ddi_port_state(struct intel_crtc *crtc,
 				       struct intel_crtc_state *pipe_config)
 {
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	enum transcoder cpu_transcoder = pipe_config->cpu_transcoder;
 	struct intel_shared_dpll *pll;
 	enum port port;
 	u32 tmp;
 
-	tmp = I915_READ(TRANS_DDI_FUNC_CTL(pipe_config->cpu_transcoder));
-
-	if (INTEL_GEN(dev_priv) >= 12)
-		port = TGL_TRANS_DDI_FUNC_CTL_VAL_TO_PORT(tmp);
-	else
-		port = TRANS_DDI_FUNC_CTL_VAL_TO_PORT(tmp);
+	if (transcoder_is_dsi(cpu_transcoder)) {
+		port = (cpu_transcoder == TRANSCODER_DSI_A) ?
+						PORT_A : PORT_B;
+	} else {
+		tmp = I915_READ(TRANS_DDI_FUNC_CTL(cpu_transcoder));
+		if (INTEL_GEN(dev_priv) >= 12)
+			port = TGL_TRANS_DDI_FUNC_CTL_VAL_TO_PORT(tmp);
+		else
+			port = TRANS_DDI_FUNC_CTL_VAL_TO_PORT(tmp);
+	}
 
 	if (INTEL_GEN(dev_priv) >= 11)
 		icelake_get_ddi_pll(dev_priv, port, pipe_config);
-- 
2.28.0