pinctrl: mediatek: add support for MTK_PULL_PD_TYPE

The MediaTek MT7988 SoC got some pins which only got configurable
pull-down but unlike previous designs there is no pull-up option.
Add new type MTK_PULL_PD_TYPE to support configuring such pins.

Signed-off-by: Daniel Golle <[e-mail]>
Signed-off-by: Frank Wunderlich <[e-mail]>
Reviewed-by: AngeloGioacchino Del Regno <[e-mail]>
Link: https://lore.kernel.org/[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c

···
  */
 static int mtk_pinconf_bias_set_pu_pd(struct mtk_pinctrl *hw,
 				const struct mtk_pin_desc *desc,
-				u32 pullup, u32 arg)
+				u32 pullup, u32 arg, bool pd_only)
 {
 	int err, pu, pd;
 
···
 		pu = 0;
 		pd = 1;
 	} else {
-		err = -EINVAL;
-		goto out;
+		return -EINVAL;
 	}
 
-	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PU, pu);
-	if (err)
-		goto out;
+	if (!pd_only) {
+		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PU, pu);
+		if (err)
+			return err;
+	}
 
-	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PD, pd);
+	return mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PD, pd);
+}
 
-out:
-	return err;
+static int mtk_pinconf_bias_set_pd(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 pullup, u32 arg)
+{
+	int err, pd;
+
+	if (arg != MTK_DISABLE && arg != MTK_ENABLE)
+		return -EINVAL;
+
+	if (arg == MTK_DISABLE || pullup)
+		pd = 0;
+	else if (!pullup)
+		pd = 1;
+
+	return mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PD, pd);
+
 }
 
 static int mtk_pinconf_bias_set_pullsel_pullen(struct mtk_pinctrl *hw,
···
 			return err;
 	}
 
-	return mtk_pinconf_bias_set_pu_pd(hw, desc, pullup, enable);
+	return mtk_pinconf_bias_set_pu_pd(hw, desc, pullup, enable, false);
 }
 
 int mtk_pinconf_bias_set_combo(struct mtk_pinctrl *hw,
···
 			return 0;
 	}
 
+	if (try_all_type & MTK_PULL_PD_TYPE) {
+		err = mtk_pinconf_bias_set_pu_pd(hw, desc, pullup, arg, true);
+		if (!err)
+			return err;
+	}
+
 	if (try_all_type & MTK_PULL_PU_PD_TYPE) {
-		err = mtk_pinconf_bias_set_pu_pd(hw, desc, pullup, arg);
+		err = mtk_pinconf_bias_set_pu_pd(hw, desc, pullup, arg, false);
 		if (!err)
 			return 0;
 	}
···
 	return err;
 }
 
+static int mtk_pinconf_bias_get_pd(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 *pullup, u32 *enable)
+{
+	int err, pd;
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_PD, &pd);
+	if (err)
+		goto out;
+
+	if (pd == 0) {
+		*pullup = 0;
+		*enable = MTK_DISABLE;
+	} else if (pd == 1) {
+		*pullup = 0;
+		*enable = MTK_ENABLE;
+	} else
+		err = -EINVAL;
+
+out:
+	return err;
+}
+
 static int mtk_pinconf_bias_get_pullsel_pullen(struct mtk_pinctrl *hw,
 				const struct mtk_pin_desc *desc,
 				u32 *pullup, u32 *enable)
···
 		err = mtk_pinconf_bias_get_pu_pd_rsel(hw, desc, pullup, enable);
 		if (!err)
 			return 0;
+	}
+
+	if (try_all_type & MTK_PULL_PD_TYPE) {
+		err = mtk_pinconf_bias_get_pd(hw, desc, pullup, enable);
+		if (!err)
+			return err;
 	}
 
 	if (try_all_type & MTK_PULL_PU_PD_TYPE) {

drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.h

···
  * turned on/off itself. But it can't be selected pull up/down
  */
 #define MTK_PULL_RSEL_TYPE		BIT(3)
+#define MTK_PULL_PD_TYPE        BIT(4)
 /* MTK_PULL_PU_PD_RSEL_TYPE is a type which is controlled by
  * MTK_PULL_PU_PD_TYPE and MTK_PULL_RSEL_TYPE.
  */