diff --git a/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c b/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c
index f2fe313..51144b8 100644
--- a/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c
+++ b/drivers/pinctrl/uniphier/pinctrl-uniphier-core.c
@@ -105,8 +105,10 @@
 				    int muxval)
 {
 	struct uniphier_pinctrl_priv *priv = dev_get_priv(dev);
-	unsigned mux_bits, reg_stride, reg, reg_end, shift, mask;
-	bool load_pinctrl;
+	unsigned reg, reg_end, shift, mask;
+	unsigned mux_bits = 8;
+	unsigned reg_stride = 4;
+	bool load_pinctrl = false;
 	u32 tmp;
 
 	/* some pins need input-enabling */
@@ -115,24 +117,18 @@
 	if (muxval < 0)
 		return;		/* dedicated pin; nothing to do for pin-mux */
 
+	if (priv->socdata->caps & UNIPHIER_PINCTRL_CAPS_MUX_4BIT)
+		mux_bits = 4;
+
 	if (priv->socdata->caps & UNIPHIER_PINCTRL_CAPS_DBGMUX_SEPARATE) {
 		/*
 		 *  Mode       offset        bit
 		 *  Normal     4 * n     shift+3:shift
 		 *  Debug      4 * n     shift+7:shift+4
 		 */
-		mux_bits = 4;
+		mux_bits /= 2;
 		reg_stride = 8;
 		load_pinctrl = true;
-	} else {
-		/*
-		 *  Mode       offset           bit
-		 *  Normal     8 * n        shift+3:shift
-		 *  Debug      8 * n + 4    shift+3:shift
-		 */
-		mux_bits = 8;
-		reg_stride = 4;
-		load_pinctrl = false;
 	}
 
 	reg = UNIPHIER_PINCTRL_PINMUX_BASE + pin * mux_bits / 32 * reg_stride;
diff --git a/drivers/pinctrl/uniphier/pinctrl-uniphier.h b/drivers/pinctrl/uniphier/pinctrl-uniphier.h
index 76ea1be..5c3db2a 100644
--- a/drivers/pinctrl/uniphier/pinctrl-uniphier.h
+++ b/drivers/pinctrl/uniphier/pinctrl-uniphier.h
@@ -67,8 +67,9 @@
 	const char * const *functions;
 	int functions_count;
 	unsigned caps;
-#define UNIPHIER_PINCTRL_CAPS_PERPIN_IECTRL	BIT(1)
-#define UNIPHIER_PINCTRL_CAPS_DBGMUX_SEPARATE	BIT(0)
+#define UNIPHIER_PINCTRL_CAPS_PERPIN_IECTRL	BIT(2)
+#define UNIPHIER_PINCTRL_CAPS_DBGMUX_SEPARATE	BIT(1)
+#define UNIPHIER_PINCTRL_CAPS_MUX_4BIT		BIT(0)
 };
 
 #define UNIPHIER_PINCTRL_PIN(a, b)					\