pinctrl: mediatek: Refine mtk_pinconf_get()

Correct cases for PIN_CONFIG_SLEW_RATE, PIN_CONFIG_INPUT_SCHMITT_ENABLE,
and PIN_CONFIG_OUTPUT_ENABLE -
Use variable ret to receive value in mtk_hw_get_value() (instead of
variable val) since pinconf_to_config_packed() at end of this function
use variable ret to pack config value.
Signed-off-by: Light Hsieh <light.hsieh@mediatek.com>
Link: https://lore.kernel.org/r/1579675994-7001-4-git-send-email-light.hsieh@mediatek.comAcked-by: Sean Wang <sean.wang@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/mediatek/pinctrl-paris.c

@@ -78,7 +78,7 @@ static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
 {
 	struct mtk_pinctrl *hw = pinctrl_dev_get_drvdata(pctldev);
 	u32 param = pinconf_to_config_param(*config);
-	int val, val2, err, reg, ret = 1;
+	int err, reg, ret = 1;
 	const struct mtk_pin_desc *desc;
 
 	if (pin >= hw->soc->npins) {
@@ -107,17 +107,11 @@ static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
 			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_SLEW_RATE:
-		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SR, &val);
-		if (err)
-			return err;
-
-		if (!val)
-			return -EINVAL;
-
+		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SR, &ret);
 		break;
 	case PIN_CONFIG_INPUT_ENABLE:
 	case PIN_CONFIG_OUTPUT_ENABLE:
-		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &val);
+		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &ret);
 		if (err)
 			goto out;
 		/*     CONFIG     Current direction return value
@@ -128,20 +122,22 @@ static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
 		 *                     input        1 (= reverse HW value)
 		 */
 		if (param == PIN_CONFIG_INPUT_ENABLE)
-			val = !val;
+			ret = !ret;
 
 		break;
 	case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
-		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &val);
+		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &ret);
 		if (err)
-			return err;
-
-		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SMT, &val2);
-		if (err)
-			return err;
+			goto out;
+		/* return error when in output mode
+		 * because schmitt trigger only work in input mode
+		 */
+		if (ret) {
+			err = -EINVAL;
+			goto out;
+		}
 
-		if (val || !val2)
-			return -EINVAL;
+		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SMT, &ret);
 
 		break;
 	case PIN_CONFIG_DRIVE_STRENGTH:
@@ -154,13 +150,7 @@ static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
 	case MTK_PIN_CONFIG_RDSEL:
 		reg = (param == MTK_PIN_CONFIG_TDSEL) ?
 		       PINCTRL_PIN_REG_TDSEL : PINCTRL_PIN_REG_RDSEL;
-
-		err = mtk_hw_get_value(hw, desc, reg, &val);
-		if (err)
-			return err;
-
-		ret = val;
-
+		err = mtk_hw_get_value(hw, desc, reg, &ret);
 		break;
 	case MTK_PIN_CONFIG_PU_ADV:
 	case MTK_PIN_CONFIG_PD_ADV: