pinctrl: mediatek: Refine mtk_pinconf_get() and mtk_pinconf_set()

1.Refine mtk_pinconf_get():
Use only one occurrence of return at end of this function.

2.Refine mtk_pinconf_set():
2.1 Use only one occurrence of return at end of this function.
2.2 Modify case of PIN_CONFIG_INPUT_ENABLE -
2.2.1
Regard all non-zero setting value as enable, instead of always enable.
2.2.2
Remove check of ies_present flag and always invoke mtk_hw_set_value()
since mtk_hw_pin_field_lookup() invoked inside mtk_hw_set_value() has
the same effect of checking if ies control is supported.
[The rationale is that: available of a control is always checked
in mtk_hw_pin_field_lookup() and no need to add ies_present flag
specially for ies control.]
2.3 Simply code logic for case of PIN_CONFIG_INPUT_SCHMITT.
2.4 Add case for PIN_CONFIG_INPUT_SCHMITT_ENABLE and process it with the
same code for case of PIN_CONFIG_INPUT_SCHMITT.

Signed-off-by: Light Hsieh <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Acked-by: Sean Wang <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/mediatek/pinctrl-mt6765.c

···
 	.ngrps = ARRAY_SIZE(mtk_pins_mt6765),
 	.eint_hw = &mt6765_eint_hw,
 	.gpio_m = 0,
-	.ies_present = true,
 	.base_names = mt6765_pinctrl_register_base_names,
 	.nbase_names = ARRAY_SIZE(mt6765_pinctrl_register_base_names),
 	.bias_disable_set = mtk_pinconf_bias_disable_set,

drivers/pinctrl/mediatek/pinctrl-mt8183.c

···
 	.ngrps = ARRAY_SIZE(mtk_pins_mt8183),
 	.eint_hw = &mt8183_eint_hw,
 	.gpio_m = 0,
-	.ies_present = true,
 	.base_names = mt8183_pinctrl_register_base_names,
 	.nbase_names = ARRAY_SIZE(mt8183_pinctrl_register_base_names),
 	.bias_disable_set = mtk_pinconf_bias_disable_set_rev1,

drivers/pinctrl/mediatek/pinctrl-paris.c

···
 	int val, val2, err, reg, ret = 1;
 	const struct mtk_pin_desc *desc;
 
-	if (pin >= hw->soc->npins)
-		return -EINVAL;
+	if (pin >= hw->soc->npins) {
+		err = -EINVAL;
+		goto out;
+	}
 	desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];
 
 	switch (param) {
 	case PIN_CONFIG_BIAS_DISABLE:
-		if (hw->soc->bias_disable_get) {
+		if (hw->soc->bias_disable_get)
 			err = hw->soc->bias_disable_get(hw, desc, &ret);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_BIAS_PULL_UP:
-		if (hw->soc->bias_get) {
+		if (hw->soc->bias_get)
 			err = hw->soc->bias_get(hw, desc, 1, &ret);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_BIAS_PULL_DOWN:
-		if (hw->soc->bias_get) {
+		if (hw->soc->bias_get)
 			err = hw->soc->bias_get(hw, desc, 0, &ret);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_SLEW_RATE:
 		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SR, &val);
···
 	case PIN_CONFIG_OUTPUT_ENABLE:
 		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &val);
 		if (err)
-			return err;
-
-		/* HW takes input mode as zero; output mode as non-zero */
-		if ((val && param == PIN_CONFIG_INPUT_ENABLE) ||
-		    (!val && param == PIN_CONFIG_OUTPUT_ENABLE))
-			return -EINVAL;
+			goto out;
+		/*     CONFIG     Current direction return value
+		 * -------------  ----------------- ----------------------
+		 * OUTPUT_ENABLE       output       1 (= HW value)
+		 *                     input        0 (= HW value)
+		 * INPUT_ENABLE        output       0 (= reverse HW value)
+		 *                     input        1 (= reverse HW value)
+		 */
+		if (param == PIN_CONFIG_INPUT_ENABLE)
+			val = !val;
 
 		break;
 	case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
···
 
 		break;
 	case PIN_CONFIG_DRIVE_STRENGTH:
-		if (hw->soc->drive_get) {
+		if (hw->soc->drive_get)
 			err = hw->soc->drive_get(hw, desc, &ret);
-			if (err)
-				return err;
-		} else {
+		else
 			err = -ENOTSUPP;
-		}
 		break;
 	case MTK_PIN_CONFIG_TDSEL:
 	case MTK_PIN_CONFIG_RDSEL:
···
 
 			pullup = param == MTK_PIN_CONFIG_PU_ADV;
 			err = hw->soc->adv_pull_get(hw, desc, pullup, &ret);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		} else
+			err = -ENOTSUPP;
 		break;
 	case MTK_PIN_CONFIG_DRV_ADV:
-		if (hw->soc->adv_drive_get) {
+		if (hw->soc->adv_drive_get)
 			err = hw->soc->adv_drive_get(hw, desc, &ret);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	default:
-		return -ENOTSUPP;
+		err = -ENOTSUPP;
 	}
 
-	*config = pinconf_to_config_packed(param, ret);
+out:
+	if (!err)
+		*config = pinconf_to_config_packed(param, ret);
 
-	return 0;
+	return err;
 }
 
 static int mtk_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
···
 
 	switch ((u32)param) {
 	case PIN_CONFIG_BIAS_DISABLE:
-		if (hw->soc->bias_disable_set) {
+		if (hw->soc->bias_disable_set)
 			err = hw->soc->bias_disable_set(hw, desc);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_BIAS_PULL_UP:
-		if (hw->soc->bias_set) {
+		if (hw->soc->bias_set)
 			err = hw->soc->bias_set(hw, desc, 1);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_BIAS_PULL_DOWN:
-		if (hw->soc->bias_set) {
+		if (hw->soc->bias_set)
 			err = hw->soc->bias_set(hw, desc, 0);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_OUTPUT_ENABLE:
 		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT,
 				       MTK_DISABLE);
-		if (err)
+		/* Keep set direction to consider the case that a GPIO pin
+		 *  does not have SMT control
+		 */
+		if (err != -ENOTSUPP)
 			goto err;
 
 		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
 				       MTK_OUTPUT);
-		if (err)
-			goto err;
 		break;
 	case PIN_CONFIG_INPUT_ENABLE:
-		if (hw->soc->ies_present) {
-			mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_IES,
-					 MTK_ENABLE);
-		}
+		/* regard all non-zero value as enable */
+		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_IES, !!arg);
+		if (err)
+			goto err;
 
 		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
 				       MTK_INPUT);
-		if (err)
-			goto err;
 		break;
 	case PIN_CONFIG_SLEW_RATE:
-		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SR,
-				       arg);
-		if (err)
-			goto err;
-
+		/* regard all non-zero value as enable */
+		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SR, !!arg);
 		break;
 	case PIN_CONFIG_OUTPUT:
 		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
···
 
 		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DO,
 				       arg);
-		if (err)
-			goto err;
 		break;
+	case PIN_CONFIG_INPUT_SCHMITT:
 	case PIN_CONFIG_INPUT_SCHMITT_ENABLE:
 		/* arg = 1: Input mode & SMT enable ;
 		 * arg = 0: Output mode & SMT disable
 		 */
-		arg = arg ? 2 : 1;
-		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR,
-				       arg & 1);
+		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DIR, !arg);
 		if (err)
 			goto err;
 
-		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT,
-				       !!(arg & 2));
-		if (err)
-			goto err;
+		err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_SMT, !!arg);
 		break;
 	case PIN_CONFIG_DRIVE_STRENGTH:
-		if (hw->soc->drive_set) {
+		if (hw->soc->drive_set)
 			err = hw->soc->drive_set(hw, desc, arg);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	case MTK_PIN_CONFIG_TDSEL:
 	case MTK_PIN_CONFIG_RDSEL:
 		reg = (param == MTK_PIN_CONFIG_TDSEL) ?
 		       PINCTRL_PIN_REG_TDSEL : PINCTRL_PIN_REG_RDSEL;
-
 		err = mtk_hw_set_value(hw, desc, reg, arg);
-		if (err)
-			goto err;
 		break;
 	case MTK_PIN_CONFIG_PU_ADV:
 	case MTK_PIN_CONFIG_PD_ADV:
···
 			pullup = param == MTK_PIN_CONFIG_PU_ADV;
 			err = hw->soc->adv_pull_set(hw, desc, pullup,
 						    arg);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		} else
+			err = -ENOTSUPP;
 		break;
 	case MTK_PIN_CONFIG_DRV_ADV:
-		if (hw->soc->adv_drive_set) {
+		if (hw->soc->adv_drive_set)
 			err = hw->soc->adv_drive_set(hw, desc, arg);
-			if (err)
-				return err;
-		} else {
-			return -ENOTSUPP;
-		}
+		else
+			err = -ENOTSUPP;
 		break;
 	default:
 		err = -ENOTSUPP;