pinctrl: mediatek: Backward compatible to previous Mediatek's bias-pull usage

Refine mtk_pinconf_set()/mtk_pinconf_get() for backward compatibility to
previous MediaTek's bias-pull usage.
In PINCTRL_MTK that use pinctrl-mtk-common.c, bias-pull setting for pins
with 2 pull resistors can be specified as value for bias-pull-up and
bias-pull-down. For example:
    bias-pull-up = <MTK_PUPD_SET_R1R0_00>;
    bias-pull-up = <MTK_PUPD_SET_R1R0_01>;
    bias-pull-up = <MTK_PUPD_SET_R1R0_10>;
    bias-pull-up = <MTK_PUPD_SET_R1R0_11>;
    bias-pull-down = <MTK_PUPD_SET_R1R0_00>;
    bias-pull-down = <MTK_PUPD_SET_R1R0_01>;
    bias-pull-down = <MTK_PUPD_SET_R1R0_10>;
    bias-pull-down = <MTK_PUPD_SET_R1R0_11>;

On the other hand, PINCTRL_MTK_PARIS use customized properties
"mediatek,pull-up-adv" and "mediatek,pull-down-adv" to specify bias-pull
setting for pins with 2 pull resistors.
This introduce in-compatibility in device tree and increase porting
effort to MediaTek's customer that had already used PINCTRL_MTK version.
Besides, if customers are not aware of this change and still write devicetree
for PINCTRL_MTK version, they may encounter runtime failure with pinctrl and
spent time to debug.

This patch adds backward compatible to previous MediaTek's bias-pull usage
so that Mediatek's customer need not use a new devicetree property name.
The rationale is that: changing driver implementation had better leave
interface unchanged.

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

Author: Light Hsieh

drivers/pinctrl/mediatek/pinctrl-mt6765.c

@@ -1072,10 +1072,8 @@ static const struct mtk_pin_soc mt6765_data = {
 	.gpio_m = 0,
 	.base_names = mt6765_pinctrl_register_base_names,
 	.nbase_names = ARRAY_SIZE(mt6765_pinctrl_register_base_names),
-	.bias_disable_set = mtk_pinconf_bias_disable_set,
-	.bias_disable_get = mtk_pinconf_bias_disable_get,
-	.bias_set = mtk_pinconf_bias_set,
-	.bias_get = mtk_pinconf_bias_get,
+	.bias_set_combo = mtk_pinconf_bias_set_combo,
+	.bias_get_combo = mtk_pinconf_bias_get_combo,
 	.drive_set = mtk_pinconf_drive_set_raw,
 	.drive_get = mtk_pinconf_drive_get_raw,
 	.adv_pull_get = mtk_pinconf_adv_pull_get,

drivers/pinctrl/mediatek/pinctrl-mt8183.c

@@ -556,10 +556,8 @@ static const struct mtk_pin_soc mt8183_data = {
 	.gpio_m = 0,
 	.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,
-	.bias_disable_get = mtk_pinconf_bias_disable_get_rev1,
-	.bias_set = mtk_pinconf_bias_set_rev1,
-	.bias_get = mtk_pinconf_bias_get_rev1,
+	.bias_set_combo = mtk_pinconf_bias_set_combo,
+	.bias_get_combo = mtk_pinconf_bias_get_combo,
 	.drive_set = mtk_pinconf_drive_set_rev1,
 	.drive_get = mtk_pinconf_drive_get_rev1,
 	.adv_pull_get = mtk_pinconf_adv_pull_get,

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

@@ -6,6 +6,7 @@
  *
  */
 
+#include <dt-bindings/pinctrl/mt65xx.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/gpio/driver.h>
@@ -517,6 +518,226 @@ int mtk_pinconf_bias_get_rev1(struct mtk_pinctrl *hw,
 	return 0;
 }
 
+/* Combo for the following pull register type:
+ * 1. PU + PD
+ * 2. PULLSEL + PULLEN
+ * 3. PUPD + R0 + R1
+ */
+static int mtk_pinconf_bias_set_pu_pd(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 pullup, u32 arg)
+{
+	int err, pu, pd;
+
+	if (arg == MTK_DISABLE) {
+		pu = 0;
+		pd = 0;
+	} else if ((arg == MTK_ENABLE) && pullup) {
+		pu = 1;
+		pd = 0;
+	} else if ((arg == MTK_ENABLE) && !pullup) {
+		pu = 0;
+		pd = 1;
+	} else {
+		err = -EINVAL;
+		goto out;
+	}
+
+	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PU, pu);
+	if (err)
+		goto out;
+
+	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PD, pd);
+
+out:
+	return err;
+}
+
+static int mtk_pinconf_bias_set_pullsel_pullen(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 pullup, u32 arg)
+{
+	int err, enable;
+
+	if (arg == MTK_DISABLE)
+		enable = 0;
+	else if (arg == MTK_ENABLE)
+		enable = 1;
+	else {
+		err = -EINVAL;
+		goto out;
+	}
+
+	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PULLEN, enable);
+	if (err)
+		goto out;
+
+	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PULLSEL, pullup);
+
+out:
+	return err;
+}
+
+static int mtk_pinconf_bias_set_pupd_r1_r0(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 pullup, u32 arg)
+{
+	int err, r0, r1;
+
+	if ((arg == MTK_DISABLE) || (arg == MTK_PUPD_SET_R1R0_00)) {
+		pullup = 0;
+		r0 = 0;
+		r1 = 0;
+	} else if (arg == MTK_PUPD_SET_R1R0_01) {
+		r0 = 1;
+		r1 = 0;
+	} else if (arg == MTK_PUPD_SET_R1R0_10) {
+		r0 = 0;
+		r1 = 1;
+	} else if (arg == MTK_PUPD_SET_R1R0_11) {
+		r0 = 1;
+		r1 = 1;
+	} else {
+		err = -EINVAL;
+		goto out;
+	}
+
+	/* MTK HW PUPD bit: 1 for pull-down, 0 for pull-up */
+	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_PUPD, !pullup);
+	if (err)
+		goto out;
+
+	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_R0, r0);
+	if (err)
+		goto out;
+
+	err = mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_R1, r1);
+
+out:
+	return err;
+}
+
+static int mtk_pinconf_bias_get_pu_pd(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 *pullup, u32 *enable)
+{
+	int err, pu, pd;
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_PU, &pu);
+	if (err)
+		goto out;
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_PD, &pd);
+	if (err)
+		goto out;
+
+	if (pu == 0 && pd == 0) {
+		*pullup = 0;
+		*enable = MTK_DISABLE;
+	} else if (pu == 1 && pd == 0) {
+		*pullup = 1;
+		*enable = MTK_ENABLE;
+	} else if (pu == 0 && 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)
+{
+	int err;
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_PULLSEL, pullup);
+	if (err)
+		goto out;
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_PULLEN, enable);
+
+out:
+	return err;
+}
+
+static int mtk_pinconf_bias_get_pupd_r1_r0(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 *pullup, u32 *enable)
+{
+	int err, r0, r1;
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_PUPD, pullup);
+	if (err)
+		goto out;
+	/* MTK HW PUPD bit: 1 for pull-down, 0 for pull-up */
+	*pullup = !(*pullup);
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_R0, &r0);
+	if (err)
+		goto out;
+
+	err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_R1, &r1);
+	if (err)
+		goto out;
+
+	if ((r1 == 0) && (r0 == 0))
+		*enable = MTK_PUPD_SET_R1R0_00;
+	else if ((r1 == 0) && (r0 == 1))
+		*enable = MTK_PUPD_SET_R1R0_01;
+	else if ((r1 == 1) && (r0 == 0))
+		*enable = MTK_PUPD_SET_R1R0_10;
+	else if ((r1 == 1) && (r0 == 1))
+		*enable = MTK_PUPD_SET_R1R0_11;
+	else
+		err = -EINVAL;
+
+out:
+	return err;
+}
+
+int mtk_pinconf_bias_set_combo(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 pullup, u32 arg)
+{
+	int err;
+
+	err = mtk_pinconf_bias_set_pu_pd(hw, desc, pullup, arg);
+	if (!err)
+		goto out;
+
+	err = mtk_pinconf_bias_set_pullsel_pullen(hw, desc, pullup, arg);
+	if (!err)
+		goto out;
+
+	err = mtk_pinconf_bias_set_pupd_r1_r0(hw, desc, pullup, arg);
+
+out:
+	return err;
+}
+
+int mtk_pinconf_bias_get_combo(struct mtk_pinctrl *hw,
+			      const struct mtk_pin_desc *desc,
+			      u32 *pullup, u32 *enable)
+{
+	int err;
+
+	err = mtk_pinconf_bias_get_pu_pd(hw, desc, pullup, enable);
+	if (!err)
+		goto out;
+
+	err = mtk_pinconf_bias_get_pullsel_pullen(hw, desc, pullup, enable);
+	if (!err)
+		goto out;
+
+	err = mtk_pinconf_bias_get_pupd_r1_r0(hw, desc, pullup, enable);
+
+out:
+	return err;
+}
+
 /* Revision 0 */
 int mtk_pinconf_drive_set(struct mtk_pinctrl *hw,
 			  const struct mtk_pin_desc *desc, u32 arg)

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

@@ -216,6 +216,11 @@ struct mtk_pin_soc {
 	int (*bias_get)(struct mtk_pinctrl *hw,
 			const struct mtk_pin_desc *desc, bool pullup, int *res);
 
+	int (*bias_set_combo)(struct mtk_pinctrl *hw,
+			const struct mtk_pin_desc *desc, u32 pullup, u32 arg);
+	int (*bias_get_combo)(struct mtk_pinctrl *hw,
+			const struct mtk_pin_desc *desc, u32 *pullup, u32 *arg);
+
 	int (*drive_set)(struct mtk_pinctrl *hw,
 			 const struct mtk_pin_desc *desc, u32 arg);
 	int (*drive_get)(struct mtk_pinctrl *hw,
@@ -277,6 +282,12 @@ int mtk_pinconf_bias_set_rev1(struct mtk_pinctrl *hw,
 int mtk_pinconf_bias_get_rev1(struct mtk_pinctrl *hw,
 			      const struct mtk_pin_desc *desc, bool pullup,
 			      int *res);
+int mtk_pinconf_bias_set_combo(struct mtk_pinctrl *hw,
+				const struct mtk_pin_desc *desc,
+				u32 pullup, u32 enable);
+int mtk_pinconf_bias_get_combo(struct mtk_pinctrl *hw,
+			      const struct mtk_pin_desc *desc,
+			      u32 *pullup, u32 *enable);
 
 int mtk_pinconf_drive_set(struct mtk_pinctrl *hw,
 			  const struct mtk_pin_desc *desc, u32 arg);

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 err, reg, ret = 1;
+	int pullup, err, reg, ret = 1;
 	const struct mtk_pin_desc *desc;
 
 	if (pin >= hw->soc->npins) {
@@ -89,22 +89,31 @@ static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
 
 	switch (param) {
 	case PIN_CONFIG_BIAS_DISABLE:
-		if (hw->soc->bias_disable_get)
-			err = hw->soc->bias_disable_get(hw, desc, &ret);
-		else
-			err = -ENOTSUPP;
-		break;
 	case PIN_CONFIG_BIAS_PULL_UP:
-		if (hw->soc->bias_get)
-			err = hw->soc->bias_get(hw, desc, 1, &ret);
-		else
-			err = -ENOTSUPP;
-		break;
 	case PIN_CONFIG_BIAS_PULL_DOWN:
-		if (hw->soc->bias_get)
-			err = hw->soc->bias_get(hw, desc, 0, &ret);
-		else
+		if (hw->soc->bias_get_combo) {
+			err = hw->soc->bias_get_combo(hw, desc, &pullup, &ret);
+			if (err)
+				goto out;
+			if (param == PIN_CONFIG_BIAS_DISABLE) {
+				if (ret == MTK_PUPD_SET_R1R0_00)
+					ret = MTK_DISABLE;
+			} else if (param == PIN_CONFIG_BIAS_PULL_UP) {
+				/* When desire to get pull-up value, return
+				 *  error if current setting is pull-down
+				 */
+				if (!pullup)
+					err = -EINVAL;
+			} else if (param == PIN_CONFIG_BIAS_PULL_DOWN) {
+				/* When desire to get pull-down value, return
+				 *  error if current setting is pull-up
+				 */
+				if (pullup)
+					err = -EINVAL;
+			}
+		} else {
 			err = -ENOTSUPP;
+		}
 		break;
 	case PIN_CONFIG_SLEW_RATE:
 		err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_SR, &ret);
@@ -196,20 +205,20 @@ 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)
-			err = hw->soc->bias_disable_set(hw, desc);
+		if (hw->soc->bias_set_combo)
+			err = hw->soc->bias_set_combo(hw, desc, 0, MTK_DISABLE);
 		else
 			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_BIAS_PULL_UP:
-		if (hw->soc->bias_set)
-			err = hw->soc->bias_set(hw, desc, 1);
+		if (hw->soc->bias_set_combo)
+			err = hw->soc->bias_set_combo(hw, desc, 1, arg);
 		else
 			err = -ENOTSUPP;
 		break;
 	case PIN_CONFIG_BIAS_PULL_DOWN:
-		if (hw->soc->bias_set)
-			err = hw->soc->bias_set(hw, desc, 0);
+		if (hw->soc->bias_set_combo)
+			err = hw->soc->bias_set_combo(hw, desc, 0, arg);
 		else
 			err = -ENOTSUPP;
 		break;