| Message ID | e1dd9e43f713ccaa29e1c05d7b21d86bff02ab34.1616150619.git.vilhelm.gray@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Introduce the Counter character device interface | expand |
On 3/19/21 12:00 PM, William Breathitt Gray wrote: > 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 <syednwaris@gmail.com> > Cc: Kamel Bouhara <kamel.bouhara@bootlin.com> > Cc: Fabrice Gasnier <fabrice.gasnier@st.com> > Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> > Cc: Alexandre Torgue <alexandre.torgue@st.com> > Cc: David Lechner <david@lechnology.com> > Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> > --- > drivers/counter/104-quad-8.c | 20 +++++++---- > drivers/counter/microchip-tcb-capture.c | 6 ++++ > drivers/counter/stm32-lptimer-cnt.c | 10 +++--- Hi William, Fro the STM32 driver, You can add my: Reviewed-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> Thanks, Fabrice > 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 = { >
On Fri, Mar 19, 2021 at 08:00:37PM +0900, William Breathitt Gray wrote: > 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 <syednwaris@gmail.com> > Cc: Kamel Bouhara <kamel.bouhara@bootlin.com> > Cc: Fabrice Gasnier <fabrice.gasnier@st.com> > Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> > Cc: Alexandre Torgue <alexandre.torgue@st.com> > Cc: David Lechner <david@lechnology.com> > Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> > --- > drivers/counter/104-quad-8.c | 20 +++++++---- For the 104-quad-8 driver: Acked-by: Syed Nayyar Waris <syednwaris@gmail.com> > 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 >
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 = {
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 <syednwaris@gmail.com> Cc: Kamel Bouhara <kamel.bouhara@bootlin.com> Cc: Fabrice Gasnier <fabrice.gasnier@st.com> Cc: Maxime Coquelin <mcoquelin.stm32@gmail.com> Cc: Alexandre Torgue <alexandre.torgue@st.com> Cc: David Lechner <david@lechnology.com> Signed-off-by: William Breathitt Gray <vilhelm.gray@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(-)