6 files changed, 45 insertions, 8 deletions

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index e5f787319725..4fd4853b2250 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1619,6 +1619,23 @@ static int intel_dp_compute_bpp(struct intel_dp *intel_dp,
         return bpp;
 }
 
+static bool intel_edp_compare_alt_mode(struct drm_display_mode *m1,
+                                       struct drm_display_mode *m2)
+{
+        bool bres = false;
+
+        if (m1 && m2)
+                bres = (m1->hdisplay == m2->hdisplay &&
+                        m1->hsync_start == m2->hsync_start &&
+                        m1->hsync_end == m2->hsync_end &&
+                        m1->htotal == m2->htotal &&
+                        m1->vdisplay == m2->vdisplay &&
+                        m1->vsync_start == m2->vsync_start &&
+                        m1->vsync_end == m2->vsync_end &&
+                        m1->vtotal == m2->vtotal);
+        return bres;
+}
+
 bool
 intel_dp_compute_config(struct intel_encoder *encoder,
                         struct intel_crtc_state *pipe_config,
@@ -1665,8 +1682,16 @@ intel_dp_compute_config(struct intel_encoder *encoder,
                 pipe_config->has_audio = intel_conn_state->force_audio == HDMI_AUDIO_ON;
 
         if (is_edp(intel_dp) && intel_connector->panel.fixed_mode) {
-                intel_fixed_panel_mode(intel_connector->panel.fixed_mode,
-                                       adjusted_mode);
+                struct drm_display_mode *panel_mode =
+                        intel_connector->panel.alt_fixed_mode;
+                struct drm_display_mode *req_mode = &pipe_config->base.mode;
+
+                if (!intel_edp_compare_alt_mode(req_mode, panel_mode))
+                        panel_mode = intel_connector->panel.fixed_mode;
+
+                drm_mode_debug_printmodeline(panel_mode);
+
+                intel_fixed_panel_mode(panel_mode, adjusted_mode);
 
                 if (INTEL_GEN(dev_priv) >= 9) {
                         int ret;
@@ -5794,6 +5819,7 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
         struct drm_device *dev = intel_encoder->base.dev;
         struct drm_i915_private *dev_priv = to_i915(dev);
         struct drm_display_mode *fixed_mode = NULL;
+        struct drm_display_mode *alt_fixed_mode = NULL;
         struct drm_display_mode *downclock_mode = NULL;
         bool has_dpcd;
         struct drm_display_mode *scan;
@@ -5849,13 +5875,14 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
         }
         intel_connector->edid = edid;
 
-        /* prefer fixed mode from EDID if available */
+        /* prefer fixed mode from EDID if available, save an alt mode also */
         list_for_each_entry(scan, &connector->probed_modes, head) {
                 if ((scan->type & DRM_MODE_TYPE_PREFERRED)) {
                         fixed_mode = drm_mode_duplicate(dev, scan);
                         downclock_mode = intel_dp_drrs_init(
                                                 intel_connector, fixed_mode);
-                        break;
+                } else if (!alt_fixed_mode) {
+                        alt_fixed_mode = drm_mode_duplicate(dev, scan);
                 }
         }
 
@@ -5892,7 +5919,8 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
                               pipe_name(pipe));
         }
 
-        intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
+        intel_panel_init(&intel_connector->panel, fixed_mode, alt_fixed_mode,
+                         downclock_mode);
         intel_connector->panel.backlight.power = intel_edp_backlight_power;
         intel_panel_setup_backlight(connector, pipe);
 
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index b1dd5d6ed0f3..fa47285918f4 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -265,6 +265,7 @@ struct intel_encoder {
 
 struct intel_panel {
         struct drm_display_mode *fixed_mode;
+        struct drm_display_mode *alt_fixed_mode;
         struct drm_display_mode *downclock_mode;
 
         /* backlight */
@@ -1678,6 +1679,7 @@ void intel_overlay_reset(struct drm_i915_private *dev_priv);
 /* intel_panel.c */
 int intel_panel_init(struct intel_panel *panel,
                      struct drm_display_mode *fixed_mode,
+                     struct drm_display_mode *alt_fixed_mode,
                      struct drm_display_mode *downclock_mode);
 void intel_panel_fini(struct intel_panel *panel);
 void intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index b0b3adf016f8..f0c11aec5ea5 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -1849,7 +1849,7 @@ void intel_dsi_init(struct drm_i915_private *dev_priv)
         connector->display_info.width_mm = fixed_mode->width_mm;
         connector->display_info.height_mm = fixed_mode->height_mm;
 
-        intel_panel_init(&intel_connector->panel, fixed_mode, NULL);
+        intel_panel_init(&intel_connector->panel, fixed_mode, NULL, NULL);
         intel_panel_setup_backlight(connector, INVALID_PIPE);
 
         intel_dsi_add_properties(intel_connector);
diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
index baf369d2de30..c0a027274c06 100644
--- a/drivers/gpu/drm/i915/intel_dvo.c
+++ b/drivers/gpu/drm/i915/intel_dvo.c
@@ -552,7 +552,7 @@ void intel_dvo_init(struct drm_i915_private *dev_priv)
                          */
                         intel_panel_init(&intel_connector->panel,
                                          intel_dvo_get_current_mode(connector),
-                                         NULL);
+                                         NULL, NULL);
                         intel_dvo->panel_wants_dither = true;
                 }
 
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 61d557948e21..8e215777c7f4 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -1138,7 +1138,8 @@ void intel_lvds_init(struct drm_i915_private *dev_priv)
 out:
         mutex_unlock(&dev->mode_config.mutex);
 
-        intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
+        intel_panel_init(&intel_connector->panel, fixed_mode, NULL,
+                         downclock_mode);
         intel_panel_setup_backlight(connector, INVALID_PIPE);
 
         lvds_encoder->is_dual_link = compute_is_dual_link_lvds(lvds_encoder);
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index 88018fccdb9f..a17b1de7d7e0 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -1920,11 +1920,13 @@ intel_panel_init_backlight_funcs(struct intel_panel *panel)
 
 int intel_panel_init(struct intel_panel *panel,
                      struct drm_display_mode *fixed_mode,
+                     struct drm_display_mode *alt_fixed_mode,
                      struct drm_display_mode *downclock_mode)
 {
         intel_panel_init_backlight_funcs(panel);
 
         panel->fixed_mode = fixed_mode;
+        panel->alt_fixed_mode = alt_fixed_mode;
         panel->downclock_mode = downclock_mode;
 
         return 0;
@@ -1938,6 +1940,10 @@ void intel_panel_fini(struct intel_panel *panel)
         if (panel->fixed_mode)
                 drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
 
+        if (panel->alt_fixed_mode)
+                drm_mode_destroy(intel_connector->base.dev,
+                                panel->alt_fixed_mode);
+
         if (panel->downclock_mode)
                 drm_mode_destroy(intel_connector->base.dev,
                                 panel->downclock_mode);