diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
index 67b139174e7b406ecedd6c75b132bd5307d28ec7..eb6195c108f39d486f5c66e9c1d1c72ebcaa9029 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.c
@@ -50,6 +50,9 @@ static const struct atmel_hlcdc_dc_desc atmel_hlcdc_dc_at91sam9n12 = {
 	.min_height = 0,
 	.max_width = 1280,
 	.max_height = 860,
+	.max_spw = 0x3f,
+	.max_vpw = 0x3f,
+	.max_hpw = 0xff,
 	.nlayers = ARRAY_SIZE(atmel_hlcdc_at91sam9n12_layers),
 	.layers = atmel_hlcdc_at91sam9n12_layers,
 };
@@ -134,6 +137,9 @@ static const struct atmel_hlcdc_dc_desc atmel_hlcdc_dc_at91sam9x5 = {
 	.min_height = 0,
 	.max_width = 800,
 	.max_height = 600,
+	.max_spw = 0x3f,
+	.max_vpw = 0x3f,
+	.max_hpw = 0xff,
 	.nlayers = ARRAY_SIZE(atmel_hlcdc_at91sam9x5_layers),
 	.layers = atmel_hlcdc_at91sam9x5_layers,
 };
@@ -237,6 +243,9 @@ static const struct atmel_hlcdc_dc_desc atmel_hlcdc_dc_sama5d3 = {
 	.min_height = 0,
 	.max_width = 2048,
 	.max_height = 2048,
+	.max_spw = 0x3f,
+	.max_vpw = 0x3f,
+	.max_hpw = 0x1ff,
 	.nlayers = ARRAY_SIZE(atmel_hlcdc_sama5d3_layers),
 	.layers = atmel_hlcdc_sama5d3_layers,
 };
@@ -320,6 +329,9 @@ static const struct atmel_hlcdc_dc_desc atmel_hlcdc_dc_sama5d4 = {
 	.min_height = 0,
 	.max_width = 2048,
 	.max_height = 2048,
+	.max_spw = 0xff,
+	.max_vpw = 0xff,
+	.max_hpw = 0x3ff,
 	.nlayers = ARRAY_SIZE(atmel_hlcdc_sama5d4_layers),
 	.layers = atmel_hlcdc_sama5d4_layers,
 };
@@ -358,19 +370,19 @@ int atmel_hlcdc_dc_mode_valid(struct atmel_hlcdc_dc *dc,
 	int hback_porch = mode->htotal - mode->hsync_end;
 	int hsync_len = mode->hsync_end - mode->hsync_start;
 
-	if (hsync_len > 0x40 || hsync_len < 1)
+	if (hsync_len > dc->desc->max_spw + 1 || hsync_len < 1)
 		return MODE_HSYNC;
 
-	if (vsync_len > 0x40 || vsync_len < 1)
+	if (vsync_len > dc->desc->max_spw + 1 || vsync_len < 1)
 		return MODE_VSYNC;
 
-	if (hfront_porch > 0x200 || hfront_porch < 1 ||
-	    hback_porch > 0x200 || hback_porch < 1 ||
+	if (hfront_porch > dc->desc->max_hpw + 1 || hfront_porch < 1 ||
+	    hback_porch > dc->desc->max_hpw + 1 || hback_porch < 1 ||
 	    mode->hdisplay < 1)
 		return MODE_H_ILLEGAL;
 
-	if (vfront_porch > 0x40 || vfront_porch < 1 ||
-	    vback_porch > 0x40 || vback_porch < 0 ||
+	if (vfront_porch > dc->desc->max_vpw + 1 || vfront_porch < 1 ||
+	    vback_porch > dc->desc->max_vpw || vback_porch < 0 ||
 	    mode->vdisplay < 1)
 		return MODE_V_ILLEGAL;
 
diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h
index 733dd1d01b1e841eab013b96585e72fb2e38209c..638e3c7293b09c30f2f6cbe1694702eec4923753 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h
@@ -50,6 +50,9 @@
  * @min_height: minimum height supported by the Display Controller
  * @max_width: maximum width supported by the Display Controller
  * @max_height: maximum height supported by the Display Controller
+ * @max_spw: maximum vertical/horizontal pulse width
+ * @max_vpw: maximum vertical back/front porch width
+ * @max_hpw: maximum horizontal back/front porch width
  * @layers: a layer description table describing available layers
  * @nlayers: layer description table size
  */
@@ -58,6 +61,9 @@ struct atmel_hlcdc_dc_desc {
 	int min_height;
 	int max_width;
 	int max_height;
+	int max_spw;
+	int max_vpw;
+	int max_hpw;
 	const struct atmel_hlcdc_layer_desc *layers;
 	int nlayers;
 };