-----Original Message-----
From: Chen-Yu Tsai <wenst@chromium.org>
To: Sean Wang <sean.wang@kernel.org>, Linus Walleij <
linus.walleij@linaro.org>, Matthias Brugger [off-list ref]
Cc: Chen-Yu Tsai <wenst@chromium.org>,
linux-mediatek@lists.infradead.org, linux-gpio@vger.kernel.org,
linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
Zhiyong Tao [off-list ref], Guodong Liu <
guodong.liu@mediatek.com>
Subject: [PATCH 2/7] pinctrl: mediatek: paris: Fix
PIN_CONFIG_BIAS_DISABLE readback
Date: Tue, 11 Jan 2022 19:22:39 +0800

When reading back pin bias settings, if the pin is not in a
bias-disabled state, the function should return -EINVAL.

Fix this in the mediatek-paris pinctrl library so that the read back
state is not littered with bogus a "input bias disabled" combined with
"pull up" or "pull down" states.

Fixes: 805250982bb5 ("pinctrl: mediatek: add pinctrl-paris that
implements the vendor dt-bindings")
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
---
 drivers/pinctrl/mediatek/pinctrl-paris.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/mediatek/pinctrl-paris.c

b/drivers/pinctrl/mediatek/pinctrl-paris.c
index f9f9110f2107..1ca598ea7ba7 100644

--- a/drivers/pinctrl/mediatek/pinctrl-paris.c
+++ b/drivers/pinctrl/mediatek/pinctrl-paris.c

@@ -97,8 +97,8 @@ static int mtk_pinconf_get(struct pinctrl_dev

*pctldev,
                        if (err)
                                goto out;
                        if (param == PIN_CONFIG_BIAS_DISABLE) {
-                               if (ret == MTK_PUPD_SET_R1R0_00)
-                                       ret = MTK_DISABLE;
+                               if (ret != MTK_PUPD_SET_R1R0_00)
+                                       err = -EINVAL;
Hi Chen-Yu

When tht API "hw->soc->bias_get_combo(hw, desc, &pullup, &ret)" is
called,
The ret vaule of may be MTK_DISABLE OR MTK_PUPD_SET_R1R0_00 or  (pullen
== 0),  All those cases are expected to be as "bias-disable".
We advices to keep original code,
+                               if (ret == MTK_PUPD_SET_R1R0_00)
+
                                ret = MTK_DISABLE;
+                               if (ret != MTK_DISABLE)
+                                       err = -EINVAL;