drm/i915: Extract intel_splitter_adjust_timings()

Let's not replicate the same piece of code to expand
the MSO segment timings to full width in many places.
Pull it into a helper
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220223131315.18016-6-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/display/intel_display.c

@@ -2728,6 +2728,30 @@ static void intel_crtc_compute_pixel_rate(struct intel_crtc_state *crtc_state)
 			ilk_pipe_pixel_rate(crtc_state);
 }
 
+static void intel_splitter_adjust_timings(const struct intel_crtc_state *crtc_state,
+					  struct drm_display_mode *mode)
+{
+	int overlap = crtc_state->splitter.pixel_overlap;
+	int n = crtc_state->splitter.link_count;
+
+	if (!crtc_state->splitter.enable)
+		return;
+
+	/*
+	 * eDP MSO uses segment timings from EDID for transcoder
+	 * timings, but full mode for everything else.
+	 *
+	 * h_full = (h_segment - pixel_overlap) * link_count
+	 */
+	mode->crtc_hdisplay = (mode->crtc_hdisplay - overlap) * n;
+	mode->crtc_hblank_start = (mode->crtc_hblank_start - overlap) * n;
+	mode->crtc_hblank_end = (mode->crtc_hblank_end - overlap) * n;
+	mode->crtc_hsync_start = (mode->crtc_hsync_start - overlap) * n;
+	mode->crtc_hsync_end = (mode->crtc_hsync_end - overlap) * n;
+	mode->crtc_htotal = (mode->crtc_htotal - overlap) * n;
+	mode->crtc_clock *= n;
+}
+
 static void intel_crtc_readout_derived_state(struct intel_crtc_state *crtc_state)
 {
 	struct drm_display_mode *mode = &crtc_state->hw.mode;
@@ -2751,22 +2775,7 @@ static void intel_crtc_readout_derived_state(struct intel_crtc_state *crtc_state
 	}
 
 	if (crtc_state->splitter.enable) {
-		int n = crtc_state->splitter.link_count;
-		int overlap = crtc_state->splitter.pixel_overlap;
-
-		/*
-		 * eDP MSO uses segment timings from EDID for transcoder
-		 * timings, but full mode for everything else.
-		 *
-		 * h_full = (h_segment - pixel_overlap) * link_count
-		 */
-		pipe_mode->crtc_hdisplay = (pipe_mode->crtc_hdisplay - overlap) * n;
-		pipe_mode->crtc_hblank_start = (pipe_mode->crtc_hblank_start - overlap) * n;
-		pipe_mode->crtc_hblank_end = (pipe_mode->crtc_hblank_end - overlap) * n;
-		pipe_mode->crtc_hsync_start = (pipe_mode->crtc_hsync_start - overlap) * n;
-		pipe_mode->crtc_hsync_end = (pipe_mode->crtc_hsync_end - overlap) * n;
-		pipe_mode->crtc_htotal = (pipe_mode->crtc_htotal - overlap) * n;
-		pipe_mode->crtc_clock *= n;
+		intel_splitter_adjust_timings(crtc_state, pipe_mode);
 
 		intel_mode_from_crtc_timings(pipe_mode, pipe_mode);
 		intel_mode_from_crtc_timings(adjusted_mode, pipe_mode);
@@ -2811,18 +2820,7 @@ static int intel_crtc_compute_config(struct intel_crtc *crtc,
 		crtc_state->pipe_src_w /= 2;
 	}
 
-	if (crtc_state->splitter.enable) {
-		int n = crtc_state->splitter.link_count;
-		int overlap = crtc_state->splitter.pixel_overlap;
-
-		pipe_mode->crtc_hdisplay = (pipe_mode->crtc_hdisplay - overlap) * n;
-		pipe_mode->crtc_hblank_start = (pipe_mode->crtc_hblank_start - overlap) * n;
-		pipe_mode->crtc_hblank_end = (pipe_mode->crtc_hblank_end - overlap) * n;
-		pipe_mode->crtc_hsync_start = (pipe_mode->crtc_hsync_start - overlap) * n;
-		pipe_mode->crtc_hsync_end = (pipe_mode->crtc_hsync_end - overlap) * n;
-		pipe_mode->crtc_htotal = (pipe_mode->crtc_htotal - overlap) * n;
-		pipe_mode->crtc_clock *= n;
-	}
+	intel_splitter_adjust_timings(crtc_state, pipe_mode);
 
 	intel_mode_from_crtc_timings(pipe_mode, pipe_mode);