pinctrl: mediatek: support rsel feature

This patch supports rsel(resistance selection) feature for I2C pins.
It provides more resistance selection solution in different ICs.
It provides rsel define and si unit solution by identifying
"mediatek,rsel_resistance_in_si_unit" property in pio dtsi node.

Signed-off-by: Zhiyong Tao <zhiyong.tao@mediatek.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20210924080632.28410-5-zhiyong.tao@mediatek.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 42 insertions, 18 deletions

diff --git a/drivers/pinctrl/mediatek/pinctrl-paris.c b/drivers/pinctrl/mediatek/pinctrl-paris.c
index 38aec0177d15..d4e02c5d74a8 100644
--- a/drivers/pinctrl/mediatek/pinctrl-paris.c
+++ b/drivers/pinctrl/mediatek/pinctrl-paris.c
@@ -579,8 +579,9 @@ static int mtk_hw_get_value_wrap(struct mtk_pinctrl *hw, unsigned int gpio, int
 ssize_t mtk_pctrl_show_one_pin(struct mtk_pinctrl *hw,
 	unsigned int gpio, char *buf, unsigned int buf_len)
 {
-	int pinmux, pullup, pullen, len = 0, r1 = -1, r0 = -1;
+	int pinmux, pullup, pullen, len = 0, r1 = -1, r0 = -1, rsel = -1;
 	const struct mtk_pin_desc *desc;
+	u32 try_all_type;
 
 	if (gpio >= hw->soc->npins)
 		return -EINVAL;
@@ -591,24 +592,39 @@ ssize_t mtk_pctrl_show_one_pin(struct mtk_pinctrl *hw,
 		pinmux -= hw->soc->nfuncs;
 
 	mtk_pinconf_bias_get_combo(hw, desc, &pullup, &pullen);
-	if (pullen == MTK_PUPD_SET_R1R0_00) {
-		pullen = 0;
-		r1 = 0;
-		r0 = 0;
-	} else if (pullen == MTK_PUPD_SET_R1R0_01) {
-		pullen = 1;
-		r1 = 0;
-		r0 = 1;
-	} else if (pullen == MTK_PUPD_SET_R1R0_10) {
-		pullen = 1;
-		r1 = 1;
-		r0 = 0;
-	} else if (pullen == MTK_PUPD_SET_R1R0_11) {
+
+	if (hw->soc->pull_type)
+		try_all_type = hw->soc->pull_type[desc->number];
+
+	if (hw->rsel_si_unit && (try_all_type & MTK_PULL_RSEL_TYPE)) {
+		rsel = pullen;
 		pullen = 1;
-		r1 = 1;
-		r0 = 1;
-	} else if (pullen != MTK_DISABLE && pullen != MTK_ENABLE) {
-		pullen = 0;
+	} else {
+		/* Case for: R1R0 */
+		if (pullen == MTK_PUPD_SET_R1R0_00) {
+			pullen = 0;
+			r1 = 0;
+			r0 = 0;
+		} else if (pullen == MTK_PUPD_SET_R1R0_01) {
+			pullen = 1;
+			r1 = 0;
+			r0 = 1;
+		} else if (pullen == MTK_PUPD_SET_R1R0_10) {
+			pullen = 1;
+			r1 = 1;
+			r0 = 0;
+		} else if (pullen == MTK_PUPD_SET_R1R0_11) {
+			pullen = 1;
+			r1 = 1;
+			r0 = 1;
+		}
+
+		/* Case for: RSEL */
+		if (pullen >= MTK_PULL_SET_RSEL_000 &&
+		    pullen <= MTK_PULL_SET_RSEL_111) {
+			rsel = pullen - MTK_PULL_SET_RSEL_000;
+			pullen = 1;
+		}
 	}
 	len += scnprintf(buf + len, buf_len - len,
 			"%03d: %1d%1d%1d%1d%02d%1d%1d%1d%1d",
@@ -626,6 +642,8 @@ ssize_t mtk_pctrl_show_one_pin(struct mtk_pinctrl *hw,
 	if (r1 != -1) {
 		len += scnprintf(buf + len, buf_len - len, " (%1d %1d)\n",
 			r1, r0);
+	} else if (rsel != -1) {
+		len += scnprintf(buf + len, buf_len - len, " (%1d)\n", rsel);
 	} else {
 		len += scnprintf(buf + len, buf_len - len, "\n");
 	}
@@ -970,6 +988,12 @@ int mtk_paris_pinctrl_probe(struct platform_device *pdev,
 
 	hw->nbase = hw->soc->nbase_names;
 
+	if (of_find_property(hw->dev->of_node,
+			     "mediatek,rsel_resistance_in_si_unit", NULL))
+		hw->rsel_si_unit = true;
+	else
+		hw->rsel_si_unit = false;
+
 	spin_lock_init(&hw->lock);
 
 	err = mtk_pctrl_build_state(pdev);