drm/msm/dpu: move INTF tearing checks to dpu_encoder_phys_cmd_init

As the INTF is fixed at the encoder creation time, we can move the
check whether INTF supports tearchck to dpu_encoder_phys_cmd_init().
This function can return an error if INTF doesn't have required feature.
Performing this check in dpu_encoder_phys_cmd_tearcheck_config() is less
useful, as this function returns void.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/555553/
Link: https://lore.kernel.org/r/20230904020454.2945667-9-dmitry.baryshkov@linaro.org

drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c

@@ -327,24 +327,21 @@ static void dpu_encoder_phys_cmd_tearcheck_config(
 	unsigned long vsync_hz;
 	struct dpu_kms *dpu_kms;
 
-	if (phys_enc->has_intf_te) {
-		if (!phys_enc->hw_intf ||
-		    !phys_enc->hw_intf->ops.enable_tearcheck) {
-			DPU_DEBUG_CMDENC(cmd_enc, "tearcheck not supported\n");
-			return;
-		}
-
-		DPU_DEBUG_CMDENC(cmd_enc, "");
-	} else {
-		if (!phys_enc->hw_pp ||
-		    !phys_enc->hw_pp->ops.enable_tearcheck) {
-			DPU_DEBUG_CMDENC(cmd_enc, "tearcheck not supported\n");
-			return;
-		}
-
-		DPU_DEBUG_CMDENC(cmd_enc, "pp %d\n", phys_enc->hw_pp->idx - PINGPONG_0);
+	/*
+	 * TODO: if/when resource allocation is refactored, move this to a
+	 * place where the driver can actually return an error.
+	 */
+	if (!phys_enc->has_intf_te &&
+	    (!phys_enc->hw_pp ||
+	     !phys_enc->hw_pp->ops.enable_tearcheck)) {
+		DPU_DEBUG_CMDENC(cmd_enc, "tearcheck not supported\n");
+		return;
 	}
 
+	DPU_DEBUG_CMDENC(cmd_enc, "intf %d pp %d\n",
+			 phys_enc->hw_intf ? phys_enc->hw_intf->idx - INTF_0 : -1,
+			 phys_enc->hw_pp ? phys_enc->hw_pp->idx - PINGPONG_0 : -1);
+
 	mode = &phys_enc->cached_mode;
 
 	dpu_kms = phys_enc->dpu_kms;
@@ -770,10 +767,20 @@ struct dpu_encoder_phys *dpu_encoder_phys_cmd_init(
 	phys_enc->intf_mode = INTF_MODE_CMD;
 	cmd_enc->stream_sel = 0;
 
+	if (!phys_enc->hw_intf) {
+		DPU_ERROR_CMDENC(cmd_enc, "no INTF provided\n");
+		return ERR_PTR(-EINVAL);
+	}
+
 	/* DPU before 5.0 use PINGPONG for TE handling */
 	if (phys_enc->dpu_kms->catalog->mdss_ver->core_major_ver >= 5)
 		phys_enc->has_intf_te = true;
 
+	if (phys_enc->has_intf_te && !phys_enc->hw_intf->ops.enable_tearcheck) {
+		DPU_ERROR_CMDENC(cmd_enc, "tearcheck not supported\n");
+		return ERR_PTR(-EINVAL);
+	}
+
 	atomic_set(&cmd_enc->pending_vblank_cnt, 0);
 	init_waitqueue_head(&cmd_enc->pending_vblank_wq);