From b11eed1554e8ea33b748094ea73d8b42fa2bbe3b Mon Sep 17 00:00:00 2001 From: William Breathitt Gray Date: Tue, 3 Aug 2021 21:06:12 +0900 Subject: [PATCH] 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 Cc: Maxime Coquelin Cc: Alexandre Torgue Acked-by: David Lechner Acked-by: Syed Nayyar Waris Reviewed-by: Fabrice Gasnier Signed-off-by: William Breathitt Gray Link: https://lore.kernel.org/r/7af82d4e39610da11edce0ee370285fe1cb1eac8.1627990337.git.vilhelm.gray@gmail.com Signed-off-by: Jonathan Cameron --- 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 | 27 ++++++++++++++++----------- 4 files changed, 42 insertions(+), 21 deletions(-) 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); diff --git a/drivers/counter/microchip-tcb-capture.c b/drivers/counter/microchip-tcb-capture.c index 51b8af8..0c9a619 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 c19d998..78f383b 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 65df9ef..c303eb1 100644 --- a/drivers/counter/ti-eqep.c +++ b/drivers/counter/ti-eqep.c @@ -157,7 +157,7 @@ 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. @@ -165,12 +165,14 @@ static int ti_eqep_action_get(struct counter_device *counter, switch (synapse->signal->id) { case TI_EQEP_SIGNAL_QEPA: *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE; - break; - default: + return 0; + case TI_EQEP_SIGNAL_QEPB: *action = TI_EQEP_SYNAPSE_ACTION_NONE; - break; + return 0; + default: + /* should never reach this path */ + return -EINVAL; } - break; 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 @@ -186,15 +188,18 @@ static int ti_eqep_action_get(struct counter_device *counter, *action = TI_EQEP_SYNAPSE_ACTION_BOTH_EDGES; else *action = TI_EQEP_SYNAPSE_ACTION_RISING_EDGE; - break; - default: + return 0; + case TI_EQEP_SIGNAL_QEPB: *action = TI_EQEP_SYNAPSE_ACTION_NONE; - break; + return 0; + default: + /* should never reach this path */ + return -EINVAL; } - break; + default: + /* should never reach this path */ + return -EINVAL; } - - return 0; } static const struct counter_ops ti_eqep_counter_ops = { -- 2.7.4