drm/ingenic: Validate mode in a .mode_valid callback

Validate modes in the drm_crtc_helper_funcs.mode_valid() callback, which
is designed for this purpose, instead of doing it in
drm_crtc_helper_funcs.atomic_check().
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200728151641.26124-3-paul@crapouillou.net

drivers/gpu/drm/ingenic/ingenic-drm-drv.c

@@ -199,21 +199,8 @@ static int ingenic_drm_crtc_atomic_check(struct drm_crtc *crtc,
 {
 	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
 	struct drm_plane_state *f1_state, *f0_state, *ipu_state = NULL;
-	long rate;
-
-	if (!drm_atomic_crtc_needs_modeset(state))
-		return 0;
-
-	if (state->mode.hdisplay > priv->soc_info->max_width ||
-	    state->mode.vdisplay > priv->soc_info->max_height)
-		return -EINVAL;
 
-	rate = clk_round_rate(priv->pix_clk,
-			      state->adjusted_mode.clock * 1000);
-	if (rate < 0)
-		return rate;
-
-	if (priv->soc_info->has_osd) {
+	if (drm_atomic_crtc_needs_modeset(state) && priv->soc_info->has_osd) {
 		f1_state = drm_atomic_get_plane_state(state->state, &priv->f1);
 		if (IS_ERR(f1_state))
 			return PTR_ERR(f1_state);
@@ -242,6 +229,24 @@ static int ingenic_drm_crtc_atomic_check(struct drm_crtc *crtc,
 	return 0;
 }
 
+static enum drm_mode_status
+ingenic_drm_crtc_mode_valid(struct drm_crtc *crtc, const struct drm_display_mode *mode)
+{
+	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+	long rate;
+
+	if (mode->hdisplay > priv->soc_info->max_width)
+		return MODE_BAD_HVALUE;
+	if (mode->vdisplay > priv->soc_info->max_height)
+		return MODE_BAD_VVALUE;
+
+	rate = clk_round_rate(priv->pix_clk, mode->clock * 1000);
+	if (rate < 0)
+		return MODE_CLOCK_RANGE;
+
+	return MODE_OK;
+}
+
 static void ingenic_drm_crtc_atomic_begin(struct drm_crtc *crtc,
 					  struct drm_crtc_state *oldstate)
 {
@@ -655,6 +660,7 @@ static const struct drm_crtc_helper_funcs ingenic_drm_crtc_helper_funcs = {
 	.atomic_begin		= ingenic_drm_crtc_atomic_begin,
 	.atomic_flush		= ingenic_drm_crtc_atomic_flush,
 	.atomic_check		= ingenic_drm_crtc_atomic_check,
+	.mode_valid		= ingenic_drm_crtc_mode_valid,
 };
 
 static const struct drm_encoder_helper_funcs ingenic_drm_encoder_helper_funcs = {