[PATCH] counter: 104-quad-8: Return error when invalid mode during ceiling_write

[William Breathitt Gray <vilhelm.gray@gmail.com>]

The 104-QUAD-8 only has two count modes where a ceiling value makes
sense: Range Limit and Modulo-N. Outside of these two modes, setting a
ceiling value is an invalid operation -- so let's report it as such by
returning -EINVAL.

Fixes: fc069262261c ("counter: 104-quad-8: Add lock guards - generic interface")
Cc: Syed Nayyar Waris <syednwaris@gmail.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
---
 drivers/counter/104-quad-8.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 09a9a77cce06..81f9642777fb 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -715,12 +715,13 @@ static ssize_t quad8_count_ceiling_write(struct counter_device *counter,
 	case 1:
 	case 3:
 		quad8_preset_register_set(priv, count->id, ceiling);
-		break;
+		mutex_unlock(&priv->lock);
+		return len;
 	}
 
 	mutex_unlock(&priv->lock);
 
-	return len;
+	return -EINVAL;
 }
 
 static ssize_t quad8_count_preset_enable_read(struct counter_device *counter,
-- 
2.32.0