From: Tzuyi Chang <tychang@realtek.com>

Treating unsupported configurations as errors causes upper layers (like the
GPIO subsystem) to interpret optional features as hard failures, aborting
operations or printing unnecessary error logs.

For example, during gpiod_get(), the GPIO framework attempts to set
PIN_CONFIG_PERSIST_STATE. Since this driver does not support it, false
error reports are generated in dmesg.

Fix this by returning -ENOTSUPP and demoting the log level to dev_dbg.

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Tzuyi Chang <tychang@realtek.com>
Signed-off-by: Yu-Chun Lin <eleanor.lin@realtek.com>
---
Changes in v2:
- Add Bartosz's Reviewed-by tag.

 drivers/pinctrl/realtek/pinctrl-rtd.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pinctrl/realtek/pinctrl-rtd.c b/drivers/pinctrl/realtek/pinctrl-rtd.c
index eafa0d7bb19d..41e7f5c2bf74 100644
--- a/drivers/pinctrl/realtek/pinctrl-rtd.c
+++ b/drivers/pinctrl/realtek/pinctrl-rtd.c
@@ -456,8 +456,8 @@ static int rtd_pconf_parse_conf(struct rtd_pinctrl *data,
 		break;
 
 	default:
-		dev_err(data->dev, "unsupported pinconf: %d\n", (u32)param);
-		return -EINVAL;
+		dev_dbg(data->dev, "unsupported pinconf: %d\n", (u32)param);
+		return -ENOTSUPP;
 	}
 
 	ret = regmap_update_bits(data->regmap_pinctrl, reg_off, mask, val);
-- 
2.34.1