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 cases for the sake of making the intent of the code clear.
Cc: Syed Nayyar Waris <syednwa...@gmail.com> Cc: Kamel Bouhara <kamel.bouh...@bootlin.com> Cc: Fabrice Gasnier <fabrice.gasn...@st.com> Cc: Maxime Coquelin <mcoquelin.st...@gmail.com> Cc: Alexandre Torgue <alexandre.tor...@st.com> Cc: David Lechner <da...@lechnology.com> Signed-off-by: William Breathitt Gray <vilhelm.g...@gmail.com> --- drivers/counter/104-quad-8.c | 20 +++++++---- drivers/counter/microchip-tcb-capture.c | 6 ++++ drivers/counter/stm32-lptimer-cnt.c | 10 +++--- drivers/counter/ti-eqep.c | 45 +++++++++++-------------- 4 files changed, 46 insertions(+), 35 deletions(-) diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c index 09d779544969..b7d6c1c43655 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); diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c index 51b8af80f98b..0c9a61962911 100644 --- a/drivers/counter/microchip-tcb-capture.c +++ b/drivers/counter/microchip-tcb-capture.c @@ -133,6 +133,9 @@ static int mchp_tc_count_function_set(struct counter_device *counter, bmr |= ATMEL_TC_QDEN | ATMEL_TC_POSEN; cmr |= ATMEL_TC_ETRGEDG_RISING | ATMEL_TC_ABETRG | ATMEL_TC_XC0; break; + default: + /* should never reach this path */ + return -EINVAL; } regmap_write(priv->regmap, ATMEL_TC_BMR, bmr); @@ -226,6 +229,9 @@ static int mchp_tc_count_action_set(struct counter_device *counter, case MCHP_TC_SYNAPSE_ACTION_BOTH_EDGE: edge = ATMEL_TC_ETRGEDG_BOTH; break; + default: + /* should never reach this path */ + return -EINVAL; } return regmap_write_bits(priv->regmap, diff --git a/drivers/counter/stm32-lptimer-cnt.c b/drivers/counter/stm32-lptimer-cnt.c index c19d998df5ba..78f383b77bd2 100644 --- a/drivers/counter/stm32-lptimer-cnt.c +++ b/drivers/counter/stm32-lptimer-cnt.c @@ -206,9 +206,10 @@ static int stm32_lptim_cnt_function_set(struct counter_device *counter, priv->quadrature_mode = 1; priv->polarity = STM32_LPTIM_SYNAPSE_ACTION_BOTH_EDGES; return 0; + default: + /* should never reach this path */ + return -EINVAL; } - - return -EINVAL; } static ssize_t stm32_lptim_cnt_enable_read(struct counter_device *counter, @@ -326,9 +327,10 @@ static int stm32_lptim_cnt_action_get(struct counter_device *counter, case STM32_LPTIM_ENCODER_BOTH_EDGE: *action = priv->polarity; return 0; + default: + /* should never reach this path */ + return -EINVAL; } - - return -EINVAL; } static int stm32_lptim_cnt_action_set(struct counter_device *counter, diff --git a/drivers/counter/ti-eqep.c b/drivers/counter/ti-eqep.c index 65df9ef5b5bc..878725c2f010 100644 --- a/drivers/counter/ti-eqep.c +++ b/drivers/counter/ti-eqep.c @@ -157,44 +157,39 @@ static int ti_eqep_action_get(struct counter_device *counter, * QEPA and QEPB trigger QCLK. */ *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES; - break; + return 0; case TI_EQEP_COUNT_FUNC_DIR_COUNT: /* In direction-count mode only rising edge of QEPA is counted * and QEPB gives direction. */ - switch (synapse->signal->id) { - case TI_EQEP_SIGNAL_QEPA: - *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE; - break; - default: + if (synapse->signal->id == TI_EQEP_SIGNAL_QEPB) *action = TI_EQEP_SYNAPSE_ACTION_NONE; - break; - } - break; + else + *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE; + return 0; case TI_EQEP_COUNT_FUNC_UP_COUNT: case TI_EQEP_COUNT_FUNC_DOWN_COUNT: /* In up/down-count modes only QEPA is counted and QEPB is not * used. */ - switch (synapse->signal->id) { - case TI_EQEP_SIGNAL_QEPA: - err = regmap_read(priv->regmap16, QDECCTL, &qdecctl); - if (err) - return err; - - if (qdecctl & QDECCTL_XCR) - *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES; - else - *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE; - break; - default: + if (synapse->signal->id == TI_EQEP_SIGNAL_QEPB) { *action = TI_EQEP_SYNAPSE_ACTION_NONE; - break; + return 0; } - break; - } - return 0; + err = regmap_read(priv->regmap16, QDECCTL, &qdecctl); + if (err) + return err; + + if (qdecctl & QDECCTL_XCR) + *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES; + else + *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE; + return 0; + default: + /* should never reach this path */ + return -EINVAL; + } } static const struct counter_ops ti_eqep_counter_ops = { -- 2.30.2