[PATCH v9 5/8] usb: misc: qcom_eud: improve enable_store API

[Elson Serrao <elson.serrao@oss.qualcomm.com>]

Currently enable_store() allows operations irrespective of the EUD state,
which can result in redundant operations. Avoid this by adding duplicate
state checks to skip requests when EUD is already in the desired state.
Additionally, improve error handling with explicit logging to provide
better feedback.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Peter Chen <peter.chen@kernel.org>
Signed-off-by: Elson Serrao <elson.serrao@oss.qualcomm.com>
---
 drivers/usb/misc/qcom_eud.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/drivers/usb/misc/qcom_eud.c b/drivers/usb/misc/qcom_eud.c
index 48e474bdf818..e227d05cfecd 100644
--- a/drivers/usb/misc/qcom_eud.c
+++ b/drivers/usb/misc/qcom_eud.c
@@ -164,18 +164,27 @@ static ssize_t enable_store(struct device *dev,
 	if (kstrtobool(buf, &enable))
 		return -EINVAL;
 
+	/* Skip operation if already in desired state */
+	if (chip->enabled == enable)
+		return count;
+
 	if (enable) {
 		ret = enable_eud(chip);
-		if (!ret)
-			chip->enabled = enable;
-		else
-			disable_eud(chip);
-
+		if (ret) {
+			dev_err(chip->dev, "failed to enable eud\n");
+			return ret;
+		}
 	} else {
 		ret = disable_eud(chip);
+		if (ret) {
+			dev_err(chip->dev, "failed to disable eud\n");
+			return ret;
+		}
 	}
 
-	return ret < 0 ? ret : count;
+	chip->enabled = enable;
+
+	return count;
 }
 
 static DEVICE_ATTR_RW(enable);
-- 
2.34.1