counter: Return error code on invalid modes
Only a select set of modes (function, action, etc.) are valid for a
given device configuration. This patch ensures that invalid modes result
in a return -EINVAL. Such a situation should never occur in reality, but
it's good to define a default switch case for the sake of making the
intent of the code clear.
Cc: Kamel Bouhara <kamel.bouhara@bootlin.com>
Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com>
Cc: Alexandre Torgue <alexandre.torgue@st.com>
Acked-by: David Lechner <david@lechnology.com>
Acked-by: Syed Nayyar Waris <syednwaris@gmail.com>
Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Link: https://lore.kernel.org/r/7af82d4e39610da11edce0ee370285fe1cb1eac8.1627990337.git.vilhelm.gray@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 81f96427..b358b2b 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -273,6 +273,10 @@ static int quad8_function_set(struct counter_device *counter,
*scale = 2;
mode_cfg |= QUAD8_CMR_QUADRATURE_X4;
break;
+ default:
+ /* should never reach this path */
+ mutex_unlock(&priv->lock);
+ return -EINVAL;
}
}
@@ -349,7 +353,7 @@ static int quad8_action_get(struct counter_device *counter,
case QUAD8_COUNT_FUNCTION_PULSE_DIRECTION:
if (synapse->signal->id == signal_a_id)
*action = QUAD8_SYNAPSE_ACTION_RISING_EDGE;
- break;
+ return 0;
case QUAD8_COUNT_FUNCTION_QUADRATURE_X1:
if (synapse->signal->id == signal_a_id) {
quad8_direction_get(counter, count, &direction);
@@ -359,17 +363,18 @@ static int quad8_action_get(struct counter_device *counter,
else
*action = QUAD8_SYNAPSE_ACTION_FALLING_EDGE;
}
- break;
+ return 0;
case QUAD8_COUNT_FUNCTION_QUADRATURE_X2:
if (synapse->signal->id == signal_a_id)
*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
- break;
+ return 0;
case QUAD8_COUNT_FUNCTION_QUADRATURE_X4:
*action = QUAD8_SYNAPSE_ACTION_BOTH_EDGES;
- break;
+ return 0;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
-
- return 0;
}
static const struct counter_ops quad8_ops = {
@@ -529,6 +534,9 @@ static int quad8_count_mode_set(struct counter_device *counter,
case COUNTER_COUNT_MODE_MODULO_N:
cnt_mode = 3;
break;
+ default:
+ /* should never reach this path */
+ return -EINVAL;
}
mutex_lock(&priv->lock);