drm/msm/dpu: handle failures while initializing displays

Bail out KMS hw init on display initialization failures with
proper error logging.

changes in v3:
    - introduced in the series
changes in v4:
    - avoid duplicate return on errors (Sean Paul)
    - avoid spamming errors on failures (Jordon Crouse)

Signed-off-by: Jeykumar Sankaran <jsanka@codeaurora.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index d39b745c3d27439fe3ac690335308eb63d5ce21f..885bf88afa3ec34a019a468ff4fde6024d10b0a7 100644 (file)
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -405,35 +405,38 @@ static void dpu_kms_wait_for_commit_done(struct msm_kms *kms,
        }
 }
 
-static void _dpu_kms_initialize_dsi(struct drm_device *dev,
+static int _dpu_kms_initialize_dsi(struct drm_device *dev,
                                    struct msm_drm_private *priv,
                                    struct dpu_kms *dpu_kms)
 {
        struct drm_encoder *encoder = NULL;
-       int i, rc;
+       int i, rc = 0;
+
+       if (!(priv->dsi[0] || priv->dsi[1]))
+               return rc;
 
        /*TODO: Support two independent DSI connectors */
        encoder = dpu_encoder_init(dev, DRM_MODE_ENCODER_DSI);
-       if (IS_ERR_OR_NULL(encoder)) {
+       if (IS_ERR(encoder)) {
                DPU_ERROR("encoder init failed for dsi display\n");
-               return;
+               return PTR_ERR(encoder);
        }
 
        priv->encoders[priv->num_encoders++] = encoder;
 
        for (i = 0; i < ARRAY_SIZE(priv->dsi); i++) {
-               if (!priv->dsi[i]) {
-                       DPU_DEBUG("invalid msm_dsi for ctrl %d\n", i);
-                       return;
-               }
+               if (!priv->dsi[i])
+                       continue;
 
                rc = msm_dsi_modeset_init(priv->dsi[i], dev, encoder);
                if (rc) {
                        DPU_ERROR("modeset_init failed for dsi[%d], rc = %d\n",
                                i, rc);
-                       continue;
+                       break;
                }
        }
+
+       return rc;
 }
 
 /**
@@ -444,16 +447,16 @@ static void _dpu_kms_initialize_dsi(struct drm_device *dev,
  * @dpu_kms:    Pointer to dpu kms structure
  * Returns:     Zero on success
  */
-static void _dpu_kms_setup_displays(struct drm_device *dev,
+static int _dpu_kms_setup_displays(struct drm_device *dev,
                                    struct msm_drm_private *priv,
                                    struct dpu_kms *dpu_kms)
 {
-       _dpu_kms_initialize_dsi(dev, priv, dpu_kms);
-
        /**
         * Extend this function to initialize other
         * types of displays
         */
+
+       return _dpu_kms_initialize_dsi(dev, priv, dpu_kms);
 }
 
 static void _dpu_kms_drm_obj_destroy(struct dpu_kms *dpu_kms)
@@ -516,7 +519,9 @@ static int _dpu_kms_drm_obj_init(struct dpu_kms *dpu_kms)
         * Create encoder and query display drivers to create
         * bridges and connectors
         */
-       _dpu_kms_setup_displays(dev, priv, dpu_kms);
+       ret = _dpu_kms_setup_displays(dev, priv, dpu_kms);
+       if (ret)
+               goto fail;
 
        max_crtc_count = min(catalog->mixer_count, priv->num_encoders);